1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, USA. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
39 #include "cp-objcp-common.h"
40 #include "tree-inline.h"
47 #include "tree-iterator.h"
50 /* The type of functions taking a tree, and some additional data, and
52 typedef int (*tree_fn_t) (tree, void*);
54 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
55 instantiations have been deferred, either because their definitions
56 were not yet available, or because we were putting off doing the work.
57 The TREE_PURPOSE of each entry is either a DECL (for a function or
58 static data member), or a TYPE (for a class) indicating what we are
59 hoping to instantiate. The TREE_VALUE is not used. */
60 static GTY(()) tree pending_templates;
61 static GTY(()) tree last_pending_template;
63 int processing_template_parmlist;
64 static int template_header_count;
66 static GTY(()) tree saved_trees;
67 static VEC(int,heap) *inline_parm_levels;
69 static GTY(()) tree current_tinst_level;
71 static GTY(()) tree saved_access_scope;
73 /* Live only within one (recursive) call to tsubst_expr. We use
74 this to pass the statement expression node from the STMT_EXPR
75 to the EXPR_STMT that is its result. */
76 static tree cur_stmt_expr;
78 /* A map from local variable declarations in the body of the template
79 presently being instantiated to the corresponding instantiated
81 static htab_t local_specializations;
83 #define UNIFY_ALLOW_NONE 0
84 #define UNIFY_ALLOW_MORE_CV_QUAL 1
85 #define UNIFY_ALLOW_LESS_CV_QUAL 2
86 #define UNIFY_ALLOW_DERIVED 4
87 #define UNIFY_ALLOW_INTEGER 8
88 #define UNIFY_ALLOW_OUTER_LEVEL 16
89 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
90 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
92 static void push_access_scope (tree);
93 static void pop_access_scope (tree);
94 static int resolve_overloaded_unification (tree, tree, tree, tree,
95 unification_kind_t, int);
96 static int try_one_overload (tree, tree, tree, tree, tree,
97 unification_kind_t, int, bool);
98 static int unify (tree, tree, tree, tree, int);
99 static void add_pending_template (tree);
100 static int push_tinst_level (tree);
101 static void pop_tinst_level (void);
102 static void reopen_tinst_level (tree);
103 static tree classtype_mangled_name (tree);
104 static char* mangle_class_name_for_template (const char *, tree, tree);
105 static tree tsubst_initializer_list (tree, tree);
106 static tree get_class_bindings (tree, tree, tree);
107 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
109 static void tsubst_enum (tree, tree, tree);
110 static tree add_to_template_args (tree, tree);
111 static tree add_outermost_template_args (tree, tree);
112 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
113 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
114 static int type_unification_real (tree, tree, tree, tree,
115 int, unification_kind_t, int);
116 static void note_template_header (int);
117 static tree convert_nontype_argument_function (tree, tree);
118 static tree convert_nontype_argument (tree, tree);
119 static tree convert_template_argument (tree, tree, tree,
120 tsubst_flags_t, int, tree);
121 static int for_each_template_parm (tree, tree_fn_t, void*,
122 struct pointer_set_t*);
123 static tree build_template_parm_index (int, int, int, tree, tree);
124 static int inline_needs_template_parms (tree);
125 static void push_inline_template_parms_recursive (tree, int);
126 static tree retrieve_local_specialization (tree);
127 static void register_local_specialization (tree, tree);
128 static tree reduce_template_parm_level (tree, tree, int);
129 static int mark_template_parm (tree, void *);
130 static int template_parm_this_level_p (tree, void *);
131 static tree tsubst_friend_function (tree, tree);
132 static tree tsubst_friend_class (tree, tree);
133 static int can_complete_type_without_circularity (tree);
134 static tree get_bindings (tree, tree, tree, bool);
135 static int template_decl_level (tree);
136 static int check_cv_quals_for_unify (int, tree, tree);
137 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
138 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
139 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
140 static void regenerate_decl_from_template (tree, tree);
141 static tree most_specialized_class (tree, tree);
142 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
143 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
144 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
145 static void check_specialization_scope (void);
146 static tree process_partial_specialization (tree);
147 static void set_current_access_from_decl (tree);
148 static void check_default_tmpl_args (tree, tree, int, int);
149 static tree get_template_base (tree, tree, tree, tree);
150 static tree try_class_unification (tree, tree, tree, tree);
151 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
153 static int template_args_equal (tree, tree);
154 static void tsubst_default_arguments (tree);
155 static tree for_each_template_parm_r (tree *, int *, void *);
156 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
157 static void copy_default_args_to_explicit_spec (tree);
158 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
159 static int eq_local_specializations (const void *, const void *);
160 static bool dependent_type_p_r (tree);
161 static tree tsubst (tree, tree, tsubst_flags_t, tree);
162 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
163 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
165 /* Make the current scope suitable for access checking when we are
166 processing T. T can be FUNCTION_DECL for instantiated function
167 template, or VAR_DECL for static member variable (need by
168 instantiate_decl). */
171 push_access_scope (tree t)
173 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
174 || TREE_CODE (t) == VAR_DECL);
176 if (DECL_FRIEND_CONTEXT (t))
177 push_nested_class (DECL_FRIEND_CONTEXT (t));
178 else if (DECL_CLASS_SCOPE_P (t))
179 push_nested_class (DECL_CONTEXT (t));
181 push_to_top_level ();
183 if (TREE_CODE (t) == FUNCTION_DECL)
185 saved_access_scope = tree_cons
186 (NULL_TREE, current_function_decl, saved_access_scope);
187 current_function_decl = t;
191 /* Restore the scope set up by push_access_scope. T is the node we
195 pop_access_scope (tree t)
197 if (TREE_CODE (t) == FUNCTION_DECL)
199 current_function_decl = TREE_VALUE (saved_access_scope);
200 saved_access_scope = TREE_CHAIN (saved_access_scope);
203 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
206 pop_from_top_level ();
209 /* Do any processing required when DECL (a member template
210 declaration) is finished. Returns the TEMPLATE_DECL corresponding
211 to DECL, unless it is a specialization, in which case the DECL
212 itself is returned. */
215 finish_member_template_decl (tree decl)
217 if (decl == error_mark_node)
218 return error_mark_node;
220 gcc_assert (DECL_P (decl));
222 if (TREE_CODE (decl) == TYPE_DECL)
226 type = TREE_TYPE (decl);
227 if (IS_AGGR_TYPE (type)
228 && CLASSTYPE_TEMPLATE_INFO (type)
229 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
231 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
232 check_member_template (tmpl);
237 else if (TREE_CODE (decl) == FIELD_DECL)
238 error ("data member %qD cannot be a member template", decl);
239 else if (DECL_TEMPLATE_INFO (decl))
241 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
243 check_member_template (DECL_TI_TEMPLATE (decl));
244 return DECL_TI_TEMPLATE (decl);
250 error ("invalid member template declaration %qD", decl);
252 return error_mark_node;
255 /* Returns the template nesting level of the indicated class TYPE.
265 A<T>::B<U> has depth two, while A<T> has depth one.
266 Both A<T>::B<int> and A<int>::B<U> have depth one, if
267 they are instantiations, not specializations.
269 This function is guaranteed to return 0 if passed NULL_TREE so
270 that, for example, `template_class_depth (current_class_type)' is
274 template_class_depth (tree type)
279 type && TREE_CODE (type) != NAMESPACE_DECL;
280 type = (TREE_CODE (type) == FUNCTION_DECL)
281 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
283 if (TREE_CODE (type) != FUNCTION_DECL)
285 if (CLASSTYPE_TEMPLATE_INFO (type)
286 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
287 && uses_template_parms (CLASSTYPE_TI_ARGS (type)))
292 if (DECL_TEMPLATE_INFO (type)
293 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
294 && uses_template_parms (DECL_TI_ARGS (type)))
302 /* Returns 1 if processing DECL as part of do_pending_inlines
303 needs us to push template parms. */
306 inline_needs_template_parms (tree decl)
308 if (! DECL_TEMPLATE_INFO (decl))
311 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
312 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
315 /* Subroutine of maybe_begin_member_template_processing.
316 Push the template parms in PARMS, starting from LEVELS steps into the
317 chain, and ending at the beginning, since template parms are listed
321 push_inline_template_parms_recursive (tree parmlist, int levels)
323 tree parms = TREE_VALUE (parmlist);
327 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
329 ++processing_template_decl;
330 current_template_parms
331 = tree_cons (size_int (processing_template_decl),
332 parms, current_template_parms);
333 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
335 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
337 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
339 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
341 if (parm == error_mark_node)
344 gcc_assert (DECL_P (parm));
346 switch (TREE_CODE (parm))
355 /* Make a CONST_DECL as is done in process_template_parm.
356 It is ugly that we recreate this here; the original
357 version built in process_template_parm is no longer
359 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
361 DECL_ARTIFICIAL (decl) = 1;
362 TREE_CONSTANT (decl) = 1;
363 TREE_INVARIANT (decl) = 1;
364 TREE_READONLY (decl) = 1;
365 DECL_INITIAL (decl) = DECL_INITIAL (parm);
366 SET_DECL_TEMPLATE_PARM_P (decl);
377 /* Restore the template parameter context for a member template or
378 a friend template defined in a class definition. */
381 maybe_begin_member_template_processing (tree decl)
386 if (inline_needs_template_parms (decl))
388 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
389 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
391 if (DECL_TEMPLATE_SPECIALIZATION (decl))
394 parms = TREE_CHAIN (parms);
397 push_inline_template_parms_recursive (parms, levels);
400 /* Remember how many levels of template parameters we pushed so that
401 we can pop them later. */
402 VEC_safe_push (int, heap, inline_parm_levels, levels);
405 /* Undo the effects of maybe_begin_member_template_processing. */
408 maybe_end_member_template_processing (void)
413 if (VEC_length (int, inline_parm_levels) == 0)
416 last = VEC_pop (int, inline_parm_levels);
417 for (i = 0; i < last; ++i)
419 --processing_template_decl;
420 current_template_parms = TREE_CHAIN (current_template_parms);
425 /* Return a new template argument vector which contains all of ARGS,
426 but has as its innermost set of arguments the EXTRA_ARGS. */
429 add_to_template_args (tree args, tree extra_args)
436 extra_depth = TMPL_ARGS_DEPTH (extra_args);
437 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
439 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
440 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
442 for (j = 1; j <= extra_depth; ++j, ++i)
443 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
448 /* Like add_to_template_args, but only the outermost ARGS are added to
449 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
450 (EXTRA_ARGS) levels are added. This function is used to combine
451 the template arguments from a partial instantiation with the
452 template arguments used to attain the full instantiation from the
453 partial instantiation. */
456 add_outermost_template_args (tree args, tree extra_args)
460 /* If there are more levels of EXTRA_ARGS than there are ARGS,
461 something very fishy is going on. */
462 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
464 /* If *all* the new arguments will be the EXTRA_ARGS, just return
466 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
469 /* For the moment, we make ARGS look like it contains fewer levels. */
470 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
472 new_args = add_to_template_args (args, extra_args);
474 /* Now, we restore ARGS to its full dimensions. */
475 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
480 /* Return the N levels of innermost template arguments from the ARGS. */
483 get_innermost_template_args (tree args, int n)
491 /* If N is 1, just return the innermost set of template arguments. */
493 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
495 /* If we're not removing anything, just return the arguments we were
497 extra_levels = TMPL_ARGS_DEPTH (args) - n;
498 gcc_assert (extra_levels >= 0);
499 if (extra_levels == 0)
502 /* Make a new set of arguments, not containing the outer arguments. */
503 new_args = make_tree_vec (n);
504 for (i = 1; i <= n; ++i)
505 SET_TMPL_ARGS_LEVEL (new_args, i,
506 TMPL_ARGS_LEVEL (args, i + extra_levels));
511 /* We've got a template header coming up; push to a new level for storing
515 begin_template_parm_list (void)
517 /* We use a non-tag-transparent scope here, which causes pushtag to
518 put tags in this scope, rather than in the enclosing class or
519 namespace scope. This is the right thing, since we want
520 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
521 global template class, push_template_decl handles putting the
522 TEMPLATE_DECL into top-level scope. For a nested template class,
525 template <class T> struct S1 {
526 template <class T> struct S2 {};
529 pushtag contains special code to call pushdecl_with_scope on the
530 TEMPLATE_DECL for S2. */
531 begin_scope (sk_template_parms, NULL);
532 ++processing_template_decl;
533 ++processing_template_parmlist;
534 note_template_header (0);
537 /* This routine is called when a specialization is declared. If it is
538 invalid to declare a specialization here, an error is reported. */
541 check_specialization_scope (void)
543 tree scope = current_scope ();
547 An explicit specialization shall be declared in the namespace of
548 which the template is a member, or, for member templates, in the
549 namespace of which the enclosing class or enclosing class
550 template is a member. An explicit specialization of a member
551 function, member class or static data member of a class template
552 shall be declared in the namespace of which the class template
554 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
555 error ("explicit specialization in non-namespace scope %qD", scope);
559 In an explicit specialization declaration for a member of a class
560 template or a member template that appears in namespace scope,
561 the member template and some of its enclosing class templates may
562 remain unspecialized, except that the declaration shall not
563 explicitly specialize a class member template if its enclosing
564 class templates are not explicitly specialized as well. */
565 if (current_template_parms)
566 error ("enclosing class templates are not explicitly specialized");
569 /* We've just seen template <>. */
572 begin_specialization (void)
574 begin_scope (sk_template_spec, NULL);
575 note_template_header (1);
576 check_specialization_scope ();
579 /* Called at then end of processing a declaration preceded by
583 end_specialization (void)
586 reset_specialization ();
589 /* Any template <>'s that we have seen thus far are not referring to a
590 function specialization. */
593 reset_specialization (void)
595 processing_specialization = 0;
596 template_header_count = 0;
599 /* We've just seen a template header. If SPECIALIZATION is nonzero,
600 it was of the form template <>. */
603 note_template_header (int specialization)
605 processing_specialization = specialization;
606 template_header_count++;
609 /* We're beginning an explicit instantiation. */
612 begin_explicit_instantiation (void)
614 gcc_assert (!processing_explicit_instantiation);
615 processing_explicit_instantiation = true;
620 end_explicit_instantiation (void)
622 gcc_assert (processing_explicit_instantiation);
623 processing_explicit_instantiation = false;
626 /* An explicit specialization or partial specialization TMPL is being
627 declared. Check that the namespace in which the specialization is
628 occurring is permissible. Returns false iff it is invalid to
629 specialize TMPL in the current namespace. */
632 check_specialization_namespace (tree tmpl)
634 tree tpl_ns = decl_namespace_context (tmpl);
638 An explicit specialization shall be declared in the namespace of
639 which the template is a member, or, for member templates, in the
640 namespace of which the enclosing class or enclosing class
641 template is a member. An explicit specialization of a member
642 function, member class or static data member of a class template
643 shall be declared in the namespace of which the class template is
645 if (is_associated_namespace (current_namespace, tpl_ns))
646 /* Same or super-using namespace. */
650 pedwarn ("specialization of %qD in different namespace", tmpl);
651 pedwarn (" from definition of %q+#D", tmpl);
656 /* SPEC is an explicit instantiation. Check that it is valid to
657 perform this explicit instantiation in the current namespace. */
660 check_explicit_instantiation_namespace (tree spec)
664 /* DR 275: An explicit instantiation shall appear in an enclosing
665 namespace of its template. */
666 ns = decl_namespace_context (spec);
667 if (!is_ancestor (current_namespace, ns))
668 pedwarn ("explicit instantiation of %qD in namespace %qD "
669 "(which does not enclose namespace %qD)",
670 spec, current_namespace, ns);
673 /* The TYPE is being declared. If it is a template type, that means it
674 is a partial specialization. Do appropriate error-checking. */
677 maybe_process_partial_specialization (tree type)
681 if (type == error_mark_node)
682 return error_mark_node;
684 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
686 error ("name of class shadows template template parameter %qD",
688 return error_mark_node;
691 context = TYPE_CONTEXT (type);
693 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
695 /* This is for ordinary explicit specialization and partial
696 specialization of a template class such as:
698 template <> class C<int>;
702 template <class T> class C<T*>;
704 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
706 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
707 && !COMPLETE_TYPE_P (type))
709 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
710 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
711 if (processing_template_decl)
712 push_template_decl (TYPE_MAIN_DECL (type));
714 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
715 error ("specialization of %qT after instantiation", type);
717 else if (CLASS_TYPE_P (type)
718 && !CLASSTYPE_USE_TEMPLATE (type)
719 && CLASSTYPE_TEMPLATE_INFO (type)
720 && context && CLASS_TYPE_P (context)
721 && CLASSTYPE_TEMPLATE_INFO (context))
723 /* This is for an explicit specialization of member class
724 template according to [temp.expl.spec/18]:
726 template <> template <class U> class C<int>::D;
728 The context `C<int>' must be an implicit instantiation.
729 Otherwise this is just a member class template declared
732 template <> class C<int> { template <class U> class D; };
733 template <> template <class U> class C<int>::D;
735 In the first case, `C<int>::D' is a specialization of `C<T>::D'
736 while in the second case, `C<int>::D' is a primary template
737 and `C<T>::D' may not exist. */
739 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
740 && !COMPLETE_TYPE_P (type))
744 if (current_namespace
745 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
747 pedwarn ("specializing %q#T in different namespace", type);
748 pedwarn (" from definition of %q+#D",
749 CLASSTYPE_TI_TEMPLATE (type));
752 /* Check for invalid specialization after instantiation:
754 template <> template <> class C<int>::D<int>;
755 template <> template <class U> class C<int>::D; */
757 for (t = DECL_TEMPLATE_INSTANTIATIONS
758 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
759 t; t = TREE_CHAIN (t))
760 if (TREE_VALUE (t) != type
761 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
762 error ("specialization %qT after instantiation %qT",
763 type, TREE_VALUE (t));
765 /* Mark TYPE as a specialization. And as a result, we only
766 have one level of template argument for the innermost
768 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
769 CLASSTYPE_TI_ARGS (type)
770 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
773 else if (processing_specialization)
775 error ("explicit specialization of non-template %qT", type);
776 return error_mark_node;
782 /* Returns nonzero if we can optimize the retrieval of specializations
783 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
784 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
787 optimize_specialization_lookup_p (tree tmpl)
789 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
790 && DECL_CLASS_SCOPE_P (tmpl)
791 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
793 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
794 /* The optimized lookup depends on the fact that the
795 template arguments for the member function template apply
796 purely to the containing class, which is not true if the
797 containing class is an explicit or partial
799 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
800 && !DECL_MEMBER_TEMPLATE_P (tmpl)
801 && !DECL_CONV_FN_P (tmpl)
802 /* It is possible to have a template that is not a member
803 template and is not a member of a template class:
805 template <typename T>
806 struct S { friend A::f(); };
808 Here, the friend function is a template, but the context does
809 not have template information. The optimized lookup relies
810 on having ARGS be the template arguments for both the class
811 and the function template. */
812 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
815 /* Retrieve the specialization (in the sense of [temp.spec] - a
816 specialization is either an instantiation or an explicit
817 specialization) of TMPL for the given template ARGS. If there is
818 no such specialization, return NULL_TREE. The ARGS are a vector of
819 arguments, or a vector of vectors of arguments, in the case of
820 templates with more than one level of parameters.
822 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
823 then we search for a partial specialization matching ARGS. This
824 parameter is ignored if TMPL is not a class template. */
827 retrieve_specialization (tree tmpl, tree args,
828 bool class_specializations_p)
830 if (args == error_mark_node)
833 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
835 /* There should be as many levels of arguments as there are
836 levels of parameters. */
837 gcc_assert (TMPL_ARGS_DEPTH (args)
838 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
840 if (optimize_specialization_lookup_p (tmpl))
843 tree class_specialization;
844 VEC(tree,gc) *methods;
848 /* The template arguments actually apply to the containing
849 class. Find the class specialization with those
851 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
853 = retrieve_specialization (class_template, args,
854 /*class_specializations_p=*/false);
855 if (!class_specialization)
857 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
858 for the specialization. */
859 idx = class_method_index_for_fn (class_specialization, tmpl);
862 /* Iterate through the methods with the indicated name, looking
863 for the one that has an instance of TMPL. */
864 methods = CLASSTYPE_METHOD_VEC (class_specialization);
865 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
867 tree fn = OVL_CURRENT (fns);
868 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
878 /* Class templates store their instantiations on the
879 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
880 DECL_TEMPLATE_SPECIALIZATIONS list. */
881 if (!class_specializations_p
882 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
883 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
885 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
887 /* Iterate through the list until we find a matching template. */
888 while (*sp != NULL_TREE)
892 if (comp_template_args (TREE_PURPOSE (spec), args))
894 /* Use the move-to-front heuristic to speed up future
898 *sp = TREE_CHAIN (*sp);
899 TREE_CHAIN (spec) = *head;
902 return TREE_VALUE (spec);
904 sp = &TREE_CHAIN (spec);
911 /* Like retrieve_specialization, but for local declarations. */
914 retrieve_local_specialization (tree tmpl)
916 tree spec = (tree) htab_find_with_hash (local_specializations, tmpl,
917 htab_hash_pointer (tmpl));
918 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
921 /* Returns nonzero iff DECL is a specialization of TMPL. */
924 is_specialization_of (tree decl, tree tmpl)
928 if (TREE_CODE (decl) == FUNCTION_DECL)
932 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
938 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
940 for (t = TREE_TYPE (decl);
942 t = CLASSTYPE_USE_TEMPLATE (t)
943 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
944 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
951 /* Returns nonzero iff DECL is a specialization of friend declaration
952 FRIEND according to [temp.friend]. */
955 is_specialization_of_friend (tree decl, tree friend)
957 bool need_template = true;
960 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
961 || TREE_CODE (decl) == TYPE_DECL);
963 /* For [temp.friend/6] when FRIEND is an ordinary member function
964 of a template class, we want to check if DECL is a specialization
966 if (TREE_CODE (friend) == FUNCTION_DECL
967 && DECL_TEMPLATE_INFO (friend)
968 && !DECL_USE_TEMPLATE (friend))
970 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
971 friend = DECL_TI_TEMPLATE (friend);
972 need_template = false;
974 else if (TREE_CODE (friend) == TEMPLATE_DECL
975 && !PRIMARY_TEMPLATE_P (friend))
976 need_template = false;
978 /* There is nothing to do if this is not a template friend. */
979 if (TREE_CODE (friend) != TEMPLATE_DECL)
982 if (is_specialization_of (decl, friend))
986 A member of a class template may be declared to be a friend of a
987 non-template class. In this case, the corresponding member of
988 every specialization of the class template is a friend of the
989 class granting friendship.
991 For example, given a template friend declaration
993 template <class T> friend void A<T>::f();
995 the member function below is considered a friend
997 template <> struct A<int> {
1001 For this type of template friend, TEMPLATE_DEPTH below will be
1002 nonzero. To determine if DECL is a friend of FRIEND, we first
1003 check if the enclosing class is a specialization of another. */
1005 template_depth = template_class_depth (DECL_CONTEXT (friend));
1007 && DECL_CLASS_SCOPE_P (decl)
1008 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1009 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
1011 /* Next, we check the members themselves. In order to handle
1012 a few tricky cases, such as when FRIEND's are
1014 template <class T> friend void A<T>::g(T t);
1015 template <class T> template <T t> friend void A<T>::h();
1019 void A<int>::g(int);
1020 template <int> void A<int>::h();
1022 we need to figure out ARGS, the template arguments from
1023 the context of DECL. This is required for template substitution
1024 of `T' in the function parameter of `g' and template parameter
1025 of `h' in the above examples. Here ARGS corresponds to `int'. */
1027 tree context = DECL_CONTEXT (decl);
1028 tree args = NULL_TREE;
1029 int current_depth = 0;
1031 while (current_depth < template_depth)
1033 if (CLASSTYPE_TEMPLATE_INFO (context))
1035 if (current_depth == 0)
1036 args = TYPE_TI_ARGS (context);
1038 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1041 context = TYPE_CONTEXT (context);
1044 if (TREE_CODE (decl) == FUNCTION_DECL)
1049 tree friend_args_type;
1050 tree decl_args_type;
1052 /* Make sure that both DECL and FRIEND are templates or
1054 is_template = DECL_TEMPLATE_INFO (decl)
1055 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1056 if (need_template ^ is_template)
1058 else if (is_template)
1060 /* If both are templates, check template parameter list. */
1062 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1064 if (!comp_template_parms
1065 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1069 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1072 decl_type = TREE_TYPE (decl);
1074 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1075 tf_none, NULL_TREE);
1076 if (friend_type == error_mark_node)
1079 /* Check if return types match. */
1080 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1083 /* Check if function parameter types match, ignoring the
1084 `this' parameter. */
1085 friend_args_type = TYPE_ARG_TYPES (friend_type);
1086 decl_args_type = TYPE_ARG_TYPES (decl_type);
1087 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1088 friend_args_type = TREE_CHAIN (friend_args_type);
1089 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1090 decl_args_type = TREE_CHAIN (decl_args_type);
1092 return compparms (decl_args_type, friend_args_type);
1096 /* DECL is a TYPE_DECL */
1098 tree decl_type = TREE_TYPE (decl);
1100 /* Make sure that both DECL and FRIEND are templates or
1103 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1104 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1106 if (need_template ^ is_template)
1108 else if (is_template)
1111 /* If both are templates, check the name of the two
1112 TEMPLATE_DECL's first because is_friend didn't. */
1113 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1114 != DECL_NAME (friend))
1117 /* Now check template parameter list. */
1119 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1121 return comp_template_parms
1122 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1126 return (DECL_NAME (decl)
1127 == DECL_NAME (friend));
1133 /* Register the specialization SPEC as a specialization of TMPL with
1134 the indicated ARGS. IS_FRIEND indicates whether the specialization
1135 is actually just a friend declaration. Returns SPEC, or an
1136 equivalent prior declaration, if available. */
1139 register_specialization (tree spec, tree tmpl, tree args, bool is_friend)
1143 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1145 if (TREE_CODE (spec) == FUNCTION_DECL
1146 && uses_template_parms (DECL_TI_ARGS (spec)))
1147 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1148 register it; we want the corresponding TEMPLATE_DECL instead.
1149 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1150 the more obvious `uses_template_parms (spec)' to avoid problems
1151 with default function arguments. In particular, given
1152 something like this:
1154 template <class T> void f(T t1, T t = T())
1156 the default argument expression is not substituted for in an
1157 instantiation unless and until it is actually needed. */
1160 fn = retrieve_specialization (tmpl, args,
1161 /*class_specializations_p=*/false);
1162 /* We can sometimes try to re-register a specialization that we've
1163 already got. In particular, regenerate_decl_from_template calls
1164 duplicate_decls which will update the specialization list. But,
1165 we'll still get called again here anyhow. It's more convenient
1166 to simply allow this than to try to prevent it. */
1169 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1171 if (DECL_TEMPLATE_INSTANTIATION (fn))
1174 || DECL_EXPLICIT_INSTANTIATION (fn))
1176 error ("specialization of %qD after instantiation",
1178 return error_mark_node;
1183 /* This situation should occur only if the first
1184 specialization is an implicit instantiation, the
1185 second is an explicit specialization, and the
1186 implicit instantiation has not yet been used. That
1187 situation can occur if we have implicitly
1188 instantiated a member function and then specialized
1191 We can also wind up here if a friend declaration that
1192 looked like an instantiation turns out to be a
1195 template <class T> void foo(T);
1196 class S { friend void foo<>(int) };
1197 template <> void foo(int);
1199 We transform the existing DECL in place so that any
1200 pointers to it become pointers to the updated
1203 If there was a definition for the template, but not
1204 for the specialization, we want this to look as if
1205 there were no definition, and vice versa. */
1206 DECL_INITIAL (fn) = NULL_TREE;
1207 duplicate_decls (spec, fn, is_friend);
1208 /* The call to duplicate_decls will have applied
1211 An explicit specialization of a function template
1212 is inline only if it is explicitly declared to be,
1213 and independently of whether its function template
1216 to the primary function; now copy the inline bits to
1217 the various clones. */
1218 FOR_EACH_CLONE (clone, fn)
1220 DECL_DECLARED_INLINE_P (clone)
1221 = DECL_DECLARED_INLINE_P (fn);
1225 check_specialization_namespace (fn);
1230 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1232 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1233 /* Dup decl failed, but this is a new definition. Set the
1234 line number so any errors match this new
1236 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1242 /* A specialization must be declared in the same namespace as the
1243 template it is specializing. */
1244 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1245 && !check_specialization_namespace (tmpl))
1246 DECL_CONTEXT (spec) = FROB_CONTEXT (decl_namespace_context (tmpl));
1248 if (!optimize_specialization_lookup_p (tmpl))
1249 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1250 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1255 /* Unregister the specialization SPEC as a specialization of TMPL.
1256 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1257 if the SPEC was listed as a specialization of TMPL. */
1260 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1264 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1266 s = &TREE_CHAIN (*s))
1267 if (TREE_VALUE (*s) == spec)
1270 *s = TREE_CHAIN (*s);
1272 TREE_VALUE (*s) = new_spec;
1279 /* Compare an entry in the local specializations hash table P1 (which
1280 is really a pointer to a TREE_LIST) with P2 (which is really a
1284 eq_local_specializations (const void *p1, const void *p2)
1286 return TREE_VALUE ((tree) p1) == (tree) p2;
1289 /* Hash P1, an entry in the local specializations table. */
1292 hash_local_specialization (const void* p1)
1294 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1297 /* Like register_specialization, but for local declarations. We are
1298 registering SPEC, an instantiation of TMPL. */
1301 register_local_specialization (tree spec, tree tmpl)
1305 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1306 htab_hash_pointer (tmpl), INSERT);
1307 *slot = build_tree_list (spec, tmpl);
1310 /* Print the list of candidate FNS in an error message. */
1313 print_candidates (tree fns)
1317 const char *str = "candidates are:";
1319 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1323 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1324 error ("%s %+#D", str, OVL_CURRENT (f));
1329 /* Returns the template (one of the functions given by TEMPLATE_ID)
1330 which can be specialized to match the indicated DECL with the
1331 explicit template args given in TEMPLATE_ID. The DECL may be
1332 NULL_TREE if none is available. In that case, the functions in
1333 TEMPLATE_ID are non-members.
1335 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1336 specialization of a member template.
1338 The TEMPLATE_COUNT is the number of references to qualifying
1339 template classes that appeared in the name of the function. See
1340 check_explicit_specialization for a more accurate description.
1342 TSK indicates what kind of template declaration (if any) is being
1343 declared. TSK_TEMPLATE indicates that the declaration given by
1344 DECL, though a FUNCTION_DECL, has template parameters, and is
1345 therefore a template function.
1347 The template args (those explicitly specified and those deduced)
1348 are output in a newly created vector *TARGS_OUT.
1350 If it is impossible to determine the result, an error message is
1351 issued. The error_mark_node is returned to indicate failure. */
1354 determine_specialization (tree template_id,
1357 int need_member_template,
1363 tree explicit_targs;
1364 tree candidates = NULL_TREE;
1365 /* A TREE_LIST of templates of which DECL may be a specialization.
1366 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1367 corresponding TREE_PURPOSE is the set of template arguments that,
1368 when used to instantiate the template, would produce a function
1369 with the signature of DECL. */
1370 tree templates = NULL_TREE;
1372 struct cp_binding_level *b;
1374 *targs_out = NULL_TREE;
1376 if (template_id == error_mark_node || decl == error_mark_node)
1377 return error_mark_node;
1379 fns = TREE_OPERAND (template_id, 0);
1380 explicit_targs = TREE_OPERAND (template_id, 1);
1382 if (fns == error_mark_node)
1383 return error_mark_node;
1385 /* Check for baselinks. */
1386 if (BASELINK_P (fns))
1387 fns = BASELINK_FUNCTIONS (fns);
1389 if (!is_overloaded_fn (fns))
1391 error ("%qD is not a function template", fns);
1392 return error_mark_node;
1395 /* Count the number of template headers specified for this
1398 for (b = current_binding_level;
1399 b->kind == sk_template_parms;
1403 for (; fns; fns = OVL_NEXT (fns))
1405 tree fn = OVL_CURRENT (fns);
1407 if (TREE_CODE (fn) == TEMPLATE_DECL)
1409 tree decl_arg_types;
1412 /* DECL might be a specialization of FN. */
1414 /* Adjust the type of DECL in case FN is a static member. */
1415 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1416 if (DECL_STATIC_FUNCTION_P (fn)
1417 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1418 decl_arg_types = TREE_CHAIN (decl_arg_types);
1420 /* Check that the number of function parameters matches.
1422 template <class T> void f(int i = 0);
1423 template <> void f<int>();
1424 The specialization f<int> is invalid but is not caught
1425 by get_bindings below. */
1427 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1428 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1431 /* For a non-static member function, we need to make sure that
1432 the const qualification is the same. This can be done by
1433 checking the 'this' in the argument list. */
1434 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1435 && !same_type_p (TREE_VALUE (fn_arg_types),
1436 TREE_VALUE (decl_arg_types)))
1439 /* In case of explicit specialization, we need to check if
1440 the number of template headers appearing in the specialization
1441 is correct. This is usually done in check_explicit_specialization,
1442 but the check done there cannot be exhaustive when specializing
1443 member functions. Consider the following code:
1445 template <> void A<int>::f(int);
1446 template <> template <> void A<int>::f(int);
1448 Assuming that A<int> is not itself an explicit specialization
1449 already, the first line specializes "f" which is a non-template
1450 member function, whilst the second line specializes "f" which
1451 is a template member function. So both lines are syntactically
1452 correct, and check_explicit_specialization does not reject
1455 Here, we can do better, as we are matching the specialization
1456 against the declarations. We count the number of template
1457 headers, and we check if they match TEMPLATE_COUNT + 1
1458 (TEMPLATE_COUNT is the number of qualifying template classes,
1459 plus there must be another header for the member template
1462 Notice that if header_count is zero, this is not a
1463 specialization but rather a template instantiation, so there
1464 is no check we can perform here. */
1465 if (header_count && header_count != template_count + 1)
1468 /* Check that the number of template arguments at the
1469 innermost level for DECL is the same as for FN. */
1470 if (current_binding_level->kind == sk_template_parms
1471 && !current_binding_level->explicit_spec_p
1472 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1473 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1474 (current_template_parms))))
1477 /* Function templates cannot be specializations; there are
1478 no partial specializations of functions. Therefore, if
1479 the type of DECL does not match FN, there is no
1481 if (tsk == tsk_template)
1483 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1485 candidates = tree_cons (NULL_TREE, fn, candidates);
1489 /* See whether this function might be a specialization of this
1491 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1494 /* We cannot deduce template arguments that when used to
1495 specialize TMPL will produce DECL. */
1498 /* Save this template, and the arguments deduced. */
1499 templates = tree_cons (targs, fn, templates);
1501 else if (need_member_template)
1502 /* FN is an ordinary member function, and we need a
1503 specialization of a member template. */
1505 else if (TREE_CODE (fn) != FUNCTION_DECL)
1506 /* We can get IDENTIFIER_NODEs here in certain erroneous
1509 else if (!DECL_FUNCTION_MEMBER_P (fn))
1510 /* This is just an ordinary non-member function. Nothing can
1511 be a specialization of that. */
1513 else if (DECL_ARTIFICIAL (fn))
1514 /* Cannot specialize functions that are created implicitly. */
1518 tree decl_arg_types;
1520 /* This is an ordinary member function. However, since
1521 we're here, we can assume it's enclosing class is a
1522 template class. For example,
1524 template <typename T> struct S { void f(); };
1525 template <> void S<int>::f() {}
1527 Here, S<int>::f is a non-template, but S<int> is a
1528 template class. If FN has the same type as DECL, we
1529 might be in business. */
1531 if (!DECL_TEMPLATE_INFO (fn))
1532 /* Its enclosing class is an explicit specialization
1533 of a template class. This is not a candidate. */
1536 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1537 TREE_TYPE (TREE_TYPE (fn))))
1538 /* The return types differ. */
1541 /* Adjust the type of DECL in case FN is a static member. */
1542 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1543 if (DECL_STATIC_FUNCTION_P (fn)
1544 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1545 decl_arg_types = TREE_CHAIN (decl_arg_types);
1547 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1550 candidates = tree_cons (NULL_TREE, fn, candidates);
1554 if (templates && TREE_CHAIN (templates))
1560 It is possible for a specialization with a given function
1561 signature to be instantiated from more than one function
1562 template. In such cases, explicit specification of the
1563 template arguments must be used to uniquely identify the
1564 function template specialization being specialized.
1566 Note that here, there's no suggestion that we're supposed to
1567 determine which of the candidate templates is most
1568 specialized. However, we, also have:
1572 Partial ordering of overloaded function template
1573 declarations is used in the following contexts to select
1574 the function template to which a function template
1575 specialization refers:
1577 -- when an explicit specialization refers to a function
1580 So, we do use the partial ordering rules, at least for now.
1581 This extension can only serve to make invalid programs valid,
1582 so it's safe. And, there is strong anecdotal evidence that
1583 the committee intended the partial ordering rules to apply;
1584 the EDG front-end has that behavior, and John Spicer claims
1585 that the committee simply forgot to delete the wording in
1586 [temp.expl.spec]. */
1587 tree tmpl = most_specialized_instantiation (templates);
1588 if (tmpl != error_mark_node)
1591 TREE_CHAIN (templates) = NULL_TREE;
1595 if (templates == NULL_TREE && candidates == NULL_TREE)
1597 error ("template-id %qD for %q+D does not match any template "
1598 "declaration", template_id, decl);
1599 return error_mark_node;
1601 else if ((templates && TREE_CHAIN (templates))
1602 || (candidates && TREE_CHAIN (candidates))
1603 || (templates && candidates))
1605 error ("ambiguous template specialization %qD for %q+D",
1607 chainon (candidates, templates);
1608 print_candidates (candidates);
1609 return error_mark_node;
1612 /* We have one, and exactly one, match. */
1615 tree fn = TREE_VALUE (candidates);
1616 /* DECL is a re-declaration of a template function. */
1617 if (TREE_CODE (fn) == TEMPLATE_DECL)
1619 /* It was a specialization of an ordinary member function in a
1621 *targs_out = copy_node (DECL_TI_ARGS (fn));
1622 return DECL_TI_TEMPLATE (fn);
1625 /* It was a specialization of a template. */
1626 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1627 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1629 *targs_out = copy_node (targs);
1630 SET_TMPL_ARGS_LEVEL (*targs_out,
1631 TMPL_ARGS_DEPTH (*targs_out),
1632 TREE_PURPOSE (templates));
1635 *targs_out = TREE_PURPOSE (templates);
1636 return TREE_VALUE (templates);
1639 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1640 but with the default argument values filled in from those in the
1644 copy_default_args_to_explicit_spec_1 (tree spec_types,
1647 tree new_spec_types;
1652 if (spec_types == void_list_node)
1653 return void_list_node;
1655 /* Substitute into the rest of the list. */
1657 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1658 TREE_CHAIN (tmpl_types));
1660 /* Add the default argument for this parameter. */
1661 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1662 TREE_VALUE (spec_types),
1666 /* DECL is an explicit specialization. Replicate default arguments
1667 from the template it specializes. (That way, code like:
1669 template <class T> void f(T = 3);
1670 template <> void f(double);
1673 works, as required.) An alternative approach would be to look up
1674 the correct default arguments at the call-site, but this approach
1675 is consistent with how implicit instantiations are handled. */
1678 copy_default_args_to_explicit_spec (tree decl)
1683 tree new_spec_types;
1687 tree object_type = NULL_TREE;
1688 tree in_charge = NULL_TREE;
1689 tree vtt = NULL_TREE;
1691 /* See if there's anything we need to do. */
1692 tmpl = DECL_TI_TEMPLATE (decl);
1693 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1694 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1695 if (TREE_PURPOSE (t))
1700 old_type = TREE_TYPE (decl);
1701 spec_types = TYPE_ARG_TYPES (old_type);
1703 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1705 /* Remove the this pointer, but remember the object's type for
1707 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1708 spec_types = TREE_CHAIN (spec_types);
1709 tmpl_types = TREE_CHAIN (tmpl_types);
1711 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1713 /* DECL may contain more parameters than TMPL due to the extra
1714 in-charge parameter in constructors and destructors. */
1715 in_charge = spec_types;
1716 spec_types = TREE_CHAIN (spec_types);
1718 if (DECL_HAS_VTT_PARM_P (decl))
1721 spec_types = TREE_CHAIN (spec_types);
1725 /* Compute the merged default arguments. */
1727 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1729 /* Compute the new FUNCTION_TYPE. */
1733 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1738 /* Put the in-charge parameter back. */
1739 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1740 TREE_VALUE (in_charge),
1743 new_type = build_method_type_directly (object_type,
1744 TREE_TYPE (old_type),
1748 new_type = build_function_type (TREE_TYPE (old_type),
1750 new_type = cp_build_type_attribute_variant (new_type,
1751 TYPE_ATTRIBUTES (old_type));
1752 new_type = build_exception_variant (new_type,
1753 TYPE_RAISES_EXCEPTIONS (old_type));
1754 TREE_TYPE (decl) = new_type;
1757 /* Check to see if the function just declared, as indicated in
1758 DECLARATOR, and in DECL, is a specialization of a function
1759 template. We may also discover that the declaration is an explicit
1760 instantiation at this point.
1762 Returns DECL, or an equivalent declaration that should be used
1763 instead if all goes well. Issues an error message if something is
1764 amiss. Returns error_mark_node if the error is not easily
1767 FLAGS is a bitmask consisting of the following flags:
1769 2: The function has a definition.
1770 4: The function is a friend.
1772 The TEMPLATE_COUNT is the number of references to qualifying
1773 template classes that appeared in the name of the function. For
1776 template <class T> struct S { void f(); };
1779 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1780 classes are not counted in the TEMPLATE_COUNT, so that in
1782 template <class T> struct S {};
1783 template <> struct S<int> { void f(); }
1784 template <> void S<int>::f();
1786 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1787 invalid; there should be no template <>.)
1789 If the function is a specialization, it is marked as such via
1790 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1791 is set up correctly, and it is added to the list of specializations
1792 for that template. */
1795 check_explicit_specialization (tree declarator,
1800 int have_def = flags & 2;
1801 int is_friend = flags & 4;
1802 int specialization = 0;
1803 int explicit_instantiation = 0;
1804 int member_specialization = 0;
1805 tree ctype = DECL_CLASS_CONTEXT (decl);
1806 tree dname = DECL_NAME (decl);
1811 if (!processing_specialization)
1814 tsk = tsk_excessive_parms;
1817 tsk = current_tmpl_spec_kind (template_count);
1822 if (processing_specialization)
1825 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1827 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1830 /* This could be something like:
1832 template <class T> void f(T);
1833 class S { friend void f<>(int); } */
1837 /* This case handles bogus declarations like template <>
1838 template <class T> void f<int>(); */
1840 error ("template-id %qD in declaration of primary template",
1847 case tsk_invalid_member_spec:
1848 /* The error has already been reported in
1849 check_specialization_scope. */
1850 return error_mark_node;
1852 case tsk_invalid_expl_inst:
1853 error ("template parameter list used in explicit instantiation");
1859 error ("definition provided for explicit instantiation");
1861 explicit_instantiation = 1;
1864 case tsk_excessive_parms:
1865 case tsk_insufficient_parms:
1866 if (tsk == tsk_excessive_parms)
1867 error ("too many template parameter lists in declaration of %qD",
1869 else if (template_header_count)
1870 error("too few template parameter lists in declaration of %qD", decl);
1872 error("explicit specialization of %qD must be introduced by "
1873 "%<template <>%>", decl);
1877 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1879 member_specialization = 1;
1885 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1887 /* This case handles bogus declarations like template <>
1888 template <class T> void f<int>(); */
1890 if (uses_template_parms (declarator))
1891 error ("function template partial specialization %qD "
1892 "is not allowed", declarator);
1894 error ("template-id %qD in declaration of primary template",
1899 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1900 /* This is a specialization of a member template, without
1901 specialization the containing class. Something like:
1903 template <class T> struct S {
1904 template <class U> void f (U);
1906 template <> template <class U> void S<int>::f(U) {}
1908 That's a specialization -- but of the entire template. */
1916 if (specialization || member_specialization)
1918 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1919 for (; t; t = TREE_CHAIN (t))
1920 if (TREE_PURPOSE (t))
1923 ("default argument specified in explicit specialization");
1928 if (specialization || member_specialization || explicit_instantiation)
1930 tree tmpl = NULL_TREE;
1931 tree targs = NULL_TREE;
1933 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1934 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1938 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1943 /* If there is no class context, the explicit instantiation
1944 must be at namespace scope. */
1945 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1947 /* Find the namespace binding, using the declaration
1949 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
1951 if (!fns || !is_overloaded_fn (fns))
1953 error ("%qD is not a template function", dname);
1954 fns = error_mark_node;
1958 tree fn = OVL_CURRENT (fns);
1959 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
1960 CP_DECL_CONTEXT (fn)))
1961 error ("%qD is not declared in %qD",
1962 decl, current_namespace);
1966 declarator = lookup_template_function (fns, NULL_TREE);
1969 if (declarator == error_mark_node)
1970 return error_mark_node;
1972 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1974 if (!explicit_instantiation)
1975 /* A specialization in class scope. This is invalid,
1976 but the error will already have been flagged by
1977 check_specialization_scope. */
1978 return error_mark_node;
1981 /* It's not valid to write an explicit instantiation in
1984 class C { template void f(); }
1986 This case is caught by the parser. However, on
1989 template class C { void f(); };
1991 (which is invalid) we can get here. The error will be
1998 else if (ctype != NULL_TREE
1999 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2002 /* Find the list of functions in ctype that have the same
2003 name as the declared function. */
2004 tree name = TREE_OPERAND (declarator, 0);
2005 tree fns = NULL_TREE;
2008 if (constructor_name_p (name, ctype))
2010 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2012 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
2013 : !CLASSTYPE_DESTRUCTORS (ctype))
2015 /* From [temp.expl.spec]:
2017 If such an explicit specialization for the member
2018 of a class template names an implicitly-declared
2019 special member function (clause _special_), the
2020 program is ill-formed.
2022 Similar language is found in [temp.explicit]. */
2023 error ("specialization of implicitly-declared special member function");
2024 return error_mark_node;
2027 name = is_constructor ? ctor_identifier : dtor_identifier;
2030 if (!DECL_CONV_FN_P (decl))
2032 idx = lookup_fnfields_1 (ctype, name);
2034 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2038 VEC(tree,gc) *methods;
2041 /* For a type-conversion operator, we cannot do a
2042 name-based lookup. We might be looking for `operator
2043 int' which will be a specialization of `operator T'.
2044 So, we find *all* the conversion operators, and then
2045 select from them. */
2048 methods = CLASSTYPE_METHOD_VEC (ctype);
2050 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2051 VEC_iterate (tree, methods, idx, ovl);
2054 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2055 /* There are no more conversion functions. */
2058 /* Glue all these conversion functions together
2059 with those we already have. */
2060 for (; ovl; ovl = OVL_NEXT (ovl))
2061 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2065 if (fns == NULL_TREE)
2067 error ("no member function %qD declared in %qT", name, ctype);
2068 return error_mark_node;
2071 TREE_OPERAND (declarator, 0) = fns;
2074 /* Figure out what exactly is being specialized at this point.
2075 Note that for an explicit instantiation, even one for a
2076 member function, we cannot tell apriori whether the
2077 instantiation is for a member template, or just a member
2078 function of a template class. Even if a member template is
2079 being instantiated, the member template arguments may be
2080 elided if they can be deduced from the rest of the
2082 tmpl = determine_specialization (declarator, decl,
2084 member_specialization,
2088 if (!tmpl || tmpl == error_mark_node)
2089 /* We couldn't figure out what this declaration was
2091 return error_mark_node;
2094 tree gen_tmpl = most_general_template (tmpl);
2096 if (explicit_instantiation)
2098 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2099 is done by do_decl_instantiation later. */
2101 int arg_depth = TMPL_ARGS_DEPTH (targs);
2102 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2104 if (arg_depth > parm_depth)
2106 /* If TMPL is not the most general template (for
2107 example, if TMPL is a friend template that is
2108 injected into namespace scope), then there will
2109 be too many levels of TARGS. Remove some of them
2114 new_targs = make_tree_vec (parm_depth);
2115 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2116 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2117 = TREE_VEC_ELT (targs, i);
2121 return instantiate_template (tmpl, targs, tf_error);
2124 /* If we thought that the DECL was a member function, but it
2125 turns out to be specializing a static member function,
2126 make DECL a static member function as well. */
2127 if (DECL_STATIC_FUNCTION_P (tmpl)
2128 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2129 revert_static_member_fn (decl);
2131 /* If this is a specialization of a member template of a
2132 template class, we want to return the TEMPLATE_DECL, not
2133 the specialization of it. */
2134 if (tsk == tsk_template)
2136 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2137 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2140 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2141 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2142 = DECL_SOURCE_LOCATION (decl);
2143 /* We want to use the argument list specified in the
2144 definition, not in the original declaration. */
2145 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2146 = DECL_ARGUMENTS (decl);
2151 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2152 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2154 /* Inherit default function arguments from the template
2155 DECL is specializing. */
2156 copy_default_args_to_explicit_spec (decl);
2158 /* This specialization has the same protection as the
2159 template it specializes. */
2160 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2161 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2163 /* If DECL is a friend declaration, declared using an
2164 unqualified name, the namespace associated with DECL may
2165 have been set incorrectly. For example, in:
2167 template <typename T> void f(T);
2169 struct S { friend void f<int>(int); }
2172 we will have set the DECL_CONTEXT for the friend
2173 declaration to N, rather than to the global namespace. */
2174 if (DECL_NAMESPACE_SCOPE_P (decl))
2175 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2177 if (is_friend && !have_def)
2178 /* This is not really a declaration of a specialization.
2179 It's just the name of an instantiation. But, it's not
2180 a request for an instantiation, either. */
2181 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2182 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2183 /* This is indeed a specialization. In case of constructors
2184 and destructors, we need in-charge and not-in-charge
2185 versions in V3 ABI. */
2186 clone_function_decl (decl, /*update_method_vec_p=*/0);
2188 /* Register this specialization so that we can find it
2190 decl = register_specialization (decl, gen_tmpl, targs, is_friend);
2197 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2198 parameters. These are represented in the same format used for
2199 DECL_TEMPLATE_PARMS. */
2202 comp_template_parms (tree parms1, tree parms2)
2207 if (parms1 == parms2)
2210 for (p1 = parms1, p2 = parms2;
2211 p1 != NULL_TREE && p2 != NULL_TREE;
2212 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2214 tree t1 = TREE_VALUE (p1);
2215 tree t2 = TREE_VALUE (p2);
2218 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2219 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2221 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2224 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2226 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2227 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2229 /* If either of the template parameters are invalid, assume
2230 they match for the sake of error recovery. */
2231 if (parm1 == error_mark_node || parm2 == error_mark_node)
2234 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2237 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2239 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2244 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2245 /* One set of parameters has more parameters lists than the
2252 /* Complain if DECL shadows a template parameter.
2254 [temp.local]: A template-parameter shall not be redeclared within its
2255 scope (including nested scopes). */
2258 check_template_shadow (tree decl)
2262 /* If we're not in a template, we can't possibly shadow a template
2264 if (!current_template_parms)
2267 /* Figure out what we're shadowing. */
2268 if (TREE_CODE (decl) == OVERLOAD)
2269 decl = OVL_CURRENT (decl);
2270 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2272 /* If there's no previous binding for this name, we're not shadowing
2273 anything, let alone a template parameter. */
2277 /* If we're not shadowing a template parameter, we're done. Note
2278 that OLDDECL might be an OVERLOAD (or perhaps even an
2279 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2281 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2284 /* We check for decl != olddecl to avoid bogus errors for using a
2285 name inside a class. We check TPFI to avoid duplicate errors for
2286 inline member templates. */
2288 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2291 error ("declaration of %q+#D", decl);
2292 error (" shadows template parm %q+#D", olddecl);
2295 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2296 ORIG_LEVEL, DECL, and TYPE. */
2299 build_template_parm_index (int index,
2305 tree t = make_node (TEMPLATE_PARM_INDEX);
2306 TEMPLATE_PARM_IDX (t) = index;
2307 TEMPLATE_PARM_LEVEL (t) = level;
2308 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2309 TEMPLATE_PARM_DECL (t) = decl;
2310 TREE_TYPE (t) = type;
2311 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2312 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2313 TREE_READONLY (t) = TREE_READONLY (decl);
2318 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2319 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2320 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2321 new one is created. */
2324 reduce_template_parm_level (tree index, tree type, int levels)
2326 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2327 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2328 != TEMPLATE_PARM_LEVEL (index) - levels))
2330 tree orig_decl = TEMPLATE_PARM_DECL (index);
2333 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2334 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2335 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2336 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2337 DECL_ARTIFICIAL (decl) = 1;
2338 SET_DECL_TEMPLATE_PARM_P (decl);
2340 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2341 TEMPLATE_PARM_LEVEL (index) - levels,
2342 TEMPLATE_PARM_ORIG_LEVEL (index),
2344 TEMPLATE_PARM_DESCENDANTS (index) = t;
2346 /* Template template parameters need this. */
2347 if (TREE_CODE (decl) != CONST_DECL)
2348 DECL_TEMPLATE_PARMS (decl)
2349 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2352 return TEMPLATE_PARM_DESCENDANTS (index);
2355 /* Process information from new template parameter PARM and append it to the
2356 LIST being built. This new parameter is a non-type parameter iff
2357 IS_NON_TYPE is true. */
2360 process_template_parm (tree list, tree parm, bool is_non_type)
2367 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2368 defval = TREE_PURPOSE (parm);
2372 tree p = tree_last (list);
2374 if (p && TREE_VALUE (p) != error_mark_node)
2377 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2378 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2380 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2390 parm = TREE_VALUE (parm);
2392 SET_DECL_TEMPLATE_PARM_P (parm);
2394 if (TREE_TYPE (parm) == error_mark_node)
2396 err_parm_list = build_tree_list (defval, parm);
2397 TREE_VALUE (err_parm_list) = error_mark_node;
2398 return chainon (list, err_parm_list);
2404 The top-level cv-qualifiers on the template-parameter are
2405 ignored when determining its type. */
2406 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2407 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2409 err_parm_list = build_tree_list (defval, parm);
2410 TREE_VALUE (err_parm_list) = error_mark_node;
2411 return chainon (list, err_parm_list);
2415 /* A template parameter is not modifiable. */
2416 TREE_CONSTANT (parm) = 1;
2417 TREE_INVARIANT (parm) = 1;
2418 TREE_READONLY (parm) = 1;
2419 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2420 TREE_CONSTANT (decl) = 1;
2421 TREE_INVARIANT (decl) = 1;
2422 TREE_READONLY (decl) = 1;
2423 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2424 = build_template_parm_index (idx, processing_template_decl,
2425 processing_template_decl,
2426 decl, TREE_TYPE (parm));
2431 parm = TREE_VALUE (TREE_VALUE (parm));
2433 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2435 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2436 /* This is for distinguishing between real templates and template
2437 template parameters */
2438 TREE_TYPE (parm) = t;
2439 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2444 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2445 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2446 decl = build_decl (TYPE_DECL, parm, t);
2449 TYPE_NAME (t) = decl;
2450 TYPE_STUB_DECL (t) = decl;
2452 TEMPLATE_TYPE_PARM_INDEX (t)
2453 = build_template_parm_index (idx, processing_template_decl,
2454 processing_template_decl,
2455 decl, TREE_TYPE (parm));
2457 DECL_ARTIFICIAL (decl) = 1;
2458 SET_DECL_TEMPLATE_PARM_P (decl);
2460 parm = build_tree_list (defval, parm);
2461 return chainon (list, parm);
2464 /* The end of a template parameter list has been reached. Process the
2465 tree list into a parameter vector, converting each parameter into a more
2466 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2470 end_template_parm_list (tree parms)
2474 tree saved_parmlist = make_tree_vec (list_length (parms));
2476 current_template_parms
2477 = tree_cons (size_int (processing_template_decl),
2478 saved_parmlist, current_template_parms);
2480 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2482 next = TREE_CHAIN (parm);
2483 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2484 TREE_CHAIN (parm) = NULL_TREE;
2487 --processing_template_parmlist;
2489 return saved_parmlist;
2492 /* end_template_decl is called after a template declaration is seen. */
2495 end_template_decl (void)
2497 reset_specialization ();
2499 if (! processing_template_decl)
2502 /* This matches the pushlevel in begin_template_parm_list. */
2505 --processing_template_decl;
2506 current_template_parms = TREE_CHAIN (current_template_parms);
2509 /* Given a template argument vector containing the template PARMS.
2510 The innermost PARMS are given first. */
2513 current_template_args (void)
2516 tree args = NULL_TREE;
2517 int length = TMPL_PARMS_DEPTH (current_template_parms);
2520 /* If there is only one level of template parameters, we do not
2521 create a TREE_VEC of TREE_VECs. Instead, we return a single
2522 TREE_VEC containing the arguments. */
2524 args = make_tree_vec (length);
2526 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2528 tree a = copy_node (TREE_VALUE (header));
2531 TREE_TYPE (a) = NULL_TREE;
2532 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2534 tree t = TREE_VEC_ELT (a, i);
2536 /* T will be a list if we are called from within a
2537 begin/end_template_parm_list pair, but a vector directly
2538 if within a begin/end_member_template_processing pair. */
2539 if (TREE_CODE (t) == TREE_LIST)
2543 if (t != error_mark_node)
2545 if (TREE_CODE (t) == TYPE_DECL
2546 || TREE_CODE (t) == TEMPLATE_DECL)
2549 t = DECL_INITIAL (t);
2552 TREE_VEC_ELT (a, i) = t;
2557 TREE_VEC_ELT (args, --l) = a;
2565 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2566 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2567 a member template. Used by push_template_decl below. */
2570 build_template_decl (tree decl, tree parms, bool member_template_p)
2572 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2573 DECL_TEMPLATE_PARMS (tmpl) = parms;
2574 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2575 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2576 if (DECL_LANG_SPECIFIC (decl))
2578 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2579 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2580 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2581 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2582 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2583 if (DECL_OVERLOADED_OPERATOR_P (decl))
2584 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2585 DECL_OVERLOADED_OPERATOR_P (decl));
2591 struct template_parm_data
2593 /* The level of the template parameters we are currently
2597 /* The index of the specialization argument we are currently
2601 /* An array whose size is the number of template parameters. The
2602 elements are nonzero if the parameter has been used in any one
2603 of the arguments processed so far. */
2606 /* An array whose size is the number of template arguments. The
2607 elements are nonzero if the argument makes use of template
2608 parameters of this level. */
2609 int* arg_uses_template_parms;
2612 /* Subroutine of push_template_decl used to see if each template
2613 parameter in a partial specialization is used in the explicit
2614 argument list. If T is of the LEVEL given in DATA (which is
2615 treated as a template_parm_data*), then DATA->PARMS is marked
2619 mark_template_parm (tree t, void* data)
2623 struct template_parm_data* tpd = (struct template_parm_data*) data;
2625 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2627 level = TEMPLATE_PARM_LEVEL (t);
2628 idx = TEMPLATE_PARM_IDX (t);
2632 level = TEMPLATE_TYPE_LEVEL (t);
2633 idx = TEMPLATE_TYPE_IDX (t);
2636 if (level == tpd->level)
2638 tpd->parms[idx] = 1;
2639 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2642 /* Return zero so that for_each_template_parm will continue the
2643 traversal of the tree; we want to mark *every* template parm. */
2647 /* Process the partial specialization DECL. */
2650 process_partial_specialization (tree decl)
2652 tree type = TREE_TYPE (decl);
2653 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2654 tree specargs = CLASSTYPE_TI_ARGS (type);
2655 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2656 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2657 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2658 int nargs = TREE_VEC_LENGTH (inner_args);
2659 int ntparms = TREE_VEC_LENGTH (inner_parms);
2661 int did_error_intro = 0;
2662 struct template_parm_data tpd;
2663 struct template_parm_data tpd2;
2665 /* We check that each of the template parameters given in the
2666 partial specialization is used in the argument list to the
2667 specialization. For example:
2669 template <class T> struct S;
2670 template <class T> struct S<T*>;
2672 The second declaration is OK because `T*' uses the template
2673 parameter T, whereas
2675 template <class T> struct S<int>;
2677 is no good. Even trickier is:
2688 The S2<T> declaration is actually invalid; it is a
2689 full-specialization. Of course,
2692 struct S2<T (*)(U)>;
2694 or some such would have been OK. */
2695 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2696 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
2697 memset (tpd.parms, 0, sizeof (int) * ntparms);
2699 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
2700 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2701 for (i = 0; i < nargs; ++i)
2703 tpd.current_arg = i;
2704 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2705 &mark_template_parm,
2709 for (i = 0; i < ntparms; ++i)
2710 if (tpd.parms[i] == 0)
2712 /* One of the template parms was not used in the
2714 if (!did_error_intro)
2716 error ("template parameters not used in partial specialization:");
2717 did_error_intro = 1;
2720 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2723 /* [temp.class.spec]
2725 The argument list of the specialization shall not be identical to
2726 the implicit argument list of the primary template. */
2727 if (comp_template_args
2729 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2731 error ("partial specialization %qT does not specialize any template arguments", type);
2733 /* [temp.class.spec]
2735 A partially specialized non-type argument expression shall not
2736 involve template parameters of the partial specialization except
2737 when the argument expression is a simple identifier.
2739 The type of a template parameter corresponding to a specialized
2740 non-type argument shall not be dependent on a parameter of the
2742 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2744 for (i = 0; i < nargs; ++i)
2746 tree arg = TREE_VEC_ELT (inner_args, i);
2747 if (/* These first two lines are the `non-type' bit. */
2749 && TREE_CODE (arg) != TEMPLATE_DECL
2750 /* This next line is the `argument expression is not just a
2751 simple identifier' condition and also the `specialized
2752 non-type argument' bit. */
2753 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2755 if (tpd.arg_uses_template_parms[i])
2756 error ("template argument %qE involves template parameter(s)", arg);
2759 /* Look at the corresponding template parameter,
2760 marking which template parameters its type depends
2763 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2768 /* We haven't yet initialized TPD2. Do so now. */
2769 tpd2.arg_uses_template_parms
2770 = (int *) alloca (sizeof (int) * nargs);
2771 /* The number of parameters here is the number in the
2772 main template, which, as checked in the assertion
2774 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
2776 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2779 /* Mark the template parameters. But this time, we're
2780 looking for the template parameters of the main
2781 template, not in the specialization. */
2782 tpd2.current_arg = i;
2783 tpd2.arg_uses_template_parms[i] = 0;
2784 memset (tpd2.parms, 0, sizeof (int) * nargs);
2785 for_each_template_parm (type,
2786 &mark_template_parm,
2790 if (tpd2.arg_uses_template_parms [i])
2792 /* The type depended on some template parameters.
2793 If they are fully specialized in the
2794 specialization, that's OK. */
2796 for (j = 0; j < nargs; ++j)
2797 if (tpd2.parms[j] != 0
2798 && tpd.arg_uses_template_parms [j])
2800 error ("type %qT of template argument %qE depends "
2801 "on template parameter(s)",
2811 if (retrieve_specialization (maintmpl, specargs,
2812 /*class_specializations_p=*/true))
2813 /* We've already got this specialization. */
2816 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2817 = tree_cons (specargs, inner_parms,
2818 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2819 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2823 /* Check that a template declaration's use of default arguments is not
2824 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2825 nonzero if DECL is the thing declared by a primary template.
2826 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2829 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2832 int last_level_to_check;
2837 A default template-argument shall not be specified in a
2838 function template declaration or a function template definition, nor
2839 in the template-parameter-list of the definition of a member of a
2842 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2843 /* You can't have a function template declaration in a local
2844 scope, nor you can you define a member of a class template in a
2848 if (current_class_type
2849 && !TYPE_BEING_DEFINED (current_class_type)
2850 && DECL_LANG_SPECIFIC (decl)
2851 /* If this is either a friend defined in the scope of the class
2852 or a member function. */
2853 && (DECL_FUNCTION_MEMBER_P (decl)
2854 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2855 : DECL_FRIEND_CONTEXT (decl)
2856 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2858 /* And, if it was a member function, it really was defined in
2859 the scope of the class. */
2860 && (!DECL_FUNCTION_MEMBER_P (decl)
2861 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2862 /* We already checked these parameters when the template was
2863 declared, so there's no need to do it again now. This function
2864 was defined in class scope, but we're processing it's body now
2865 that the class is complete. */
2870 If a template-parameter has a default template-argument, all
2871 subsequent template-parameters shall have a default
2872 template-argument supplied. */
2873 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2875 tree inner_parms = TREE_VALUE (parm_level);
2876 int ntparms = TREE_VEC_LENGTH (inner_parms);
2877 int seen_def_arg_p = 0;
2880 for (i = 0; i < ntparms; ++i)
2882 tree parm = TREE_VEC_ELT (inner_parms, i);
2884 if (parm == error_mark_node)
2887 if (TREE_PURPOSE (parm))
2889 else if (seen_def_arg_p)
2891 error ("no default argument for %qD", TREE_VALUE (parm));
2892 /* For better subsequent error-recovery, we indicate that
2893 there should have been a default argument. */
2894 TREE_PURPOSE (parm) = error_mark_node;
2899 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2900 /* For an ordinary class template, default template arguments are
2901 allowed at the innermost level, e.g.:
2902 template <class T = int>
2904 but, in a partial specialization, they're not allowed even
2905 there, as we have in [temp.class.spec]:
2907 The template parameter list of a specialization shall not
2908 contain default template argument values.
2910 So, for a partial specialization, or for a function template,
2911 we look at all of them. */
2914 /* But, for a primary class template that is not a partial
2915 specialization we look at all template parameters except the
2917 parms = TREE_CHAIN (parms);
2919 /* Figure out what error message to issue. */
2920 if (TREE_CODE (decl) == FUNCTION_DECL)
2921 msg = "default template arguments may not be used in function templates";
2922 else if (is_partial)
2923 msg = "default template arguments may not be used in partial specializations";
2925 msg = "default argument for template parameter for class enclosing %qD";
2927 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2928 /* If we're inside a class definition, there's no need to
2929 examine the parameters to the class itself. On the one
2930 hand, they will be checked when the class is defined, and,
2931 on the other, default arguments are valid in things like:
2932 template <class T = double>
2933 struct S { template <class U> void f(U); };
2934 Here the default argument for `S' has no bearing on the
2935 declaration of `f'. */
2936 last_level_to_check = template_class_depth (current_class_type) + 1;
2938 /* Check everything. */
2939 last_level_to_check = 0;
2941 for (parm_level = parms;
2942 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2943 parm_level = TREE_CHAIN (parm_level))
2945 tree inner_parms = TREE_VALUE (parm_level);
2949 ntparms = TREE_VEC_LENGTH (inner_parms);
2950 for (i = 0; i < ntparms; ++i)
2952 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
2955 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2963 /* Clear out the default argument so that we are not
2965 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2969 /* At this point, if we're still interested in issuing messages,
2970 they must apply to classes surrounding the object declared. */
2972 msg = "default argument for template parameter for class enclosing %qD";
2976 /* Worker for push_template_decl_real, called via
2977 for_each_template_parm. DATA is really an int, indicating the
2978 level of the parameters we are interested in. If T is a template
2979 parameter of that level, return nonzero. */
2982 template_parm_this_level_p (tree t, void* data)
2984 int this_level = *(int *)data;
2987 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2988 level = TEMPLATE_PARM_LEVEL (t);
2990 level = TEMPLATE_TYPE_LEVEL (t);
2991 return level == this_level;
2994 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2995 parameters given by current_template_args, or reuses a
2996 previously existing one, if appropriate. Returns the DECL, or an
2997 equivalent one, if it is replaced via a call to duplicate_decls.
2999 If IS_FRIEND is true, DECL is a friend declaration. */
3002 push_template_decl_real (tree decl, bool is_friend)
3010 int new_template_p = 0;
3011 /* True if the template is a member template, in the sense of
3013 bool member_template_p = false;
3015 if (decl == error_mark_node)
3018 /* See if this is a partial specialization. */
3019 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
3020 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3021 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
3023 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
3027 /* For a friend, we want the context of the friend function, not
3028 the type of which it is a friend. */
3029 ctx = DECL_CONTEXT (decl);
3030 else if (CP_DECL_CONTEXT (decl)
3031 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
3032 /* In the case of a virtual function, we want the class in which
3034 ctx = CP_DECL_CONTEXT (decl);
3036 /* Otherwise, if we're currently defining some class, the DECL
3037 is assumed to be a member of the class. */
3038 ctx = current_scope ();
3040 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
3043 if (!DECL_CONTEXT (decl))
3044 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
3046 /* See if this is a primary template. */
3047 if (is_friend && ctx)
3048 /* A friend template that specifies a class context, i.e.
3049 template <typename T> friend void A<T>::f();
3053 primary = template_parm_scope_p ();
3057 if (DECL_CLASS_SCOPE_P (decl))
3058 member_template_p = true;
3059 if (TREE_CODE (decl) == TYPE_DECL
3060 && ANON_AGGRNAME_P (DECL_NAME (decl)))
3061 error ("template class without a name");
3062 else if (TREE_CODE (decl) == FUNCTION_DECL)
3064 if (DECL_DESTRUCTOR_P (decl))
3068 A destructor shall not be a member template. */
3069 error ("destructor %qD declared as member template", decl);
3070 return error_mark_node;
3072 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
3073 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
3074 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
3075 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
3076 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
3077 == void_list_node)))
3079 /* [basic.stc.dynamic.allocation]
3081 An allocation function can be a function
3082 template. ... Template allocation functions shall
3083 have two or more parameters. */
3084 error ("invalid template declaration of %qD", decl);
3085 return error_mark_node;
3088 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3089 && CLASS_TYPE_P (TREE_TYPE (decl)))
3093 error ("template declaration of %q#D", decl);
3094 return error_mark_node;
3098 /* Check to see that the rules regarding the use of default
3099 arguments are not being violated. */
3100 check_default_tmpl_args (decl, current_template_parms,
3101 primary, is_partial);
3104 return process_partial_specialization (decl);
3106 args = current_template_args ();
3109 || TREE_CODE (ctx) == FUNCTION_DECL
3110 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3111 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3113 if (DECL_LANG_SPECIFIC (decl)
3114 && DECL_TEMPLATE_INFO (decl)
3115 && DECL_TI_TEMPLATE (decl))
3116 tmpl = DECL_TI_TEMPLATE (decl);
3117 /* If DECL is a TYPE_DECL for a class-template, then there won't
3118 be DECL_LANG_SPECIFIC. The information equivalent to
3119 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3120 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3121 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3122 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3124 /* Since a template declaration already existed for this
3125 class-type, we must be redeclaring it here. Make sure
3126 that the redeclaration is valid. */
3127 redeclare_class_template (TREE_TYPE (decl),
3128 current_template_parms);
3129 /* We don't need to create a new TEMPLATE_DECL; just use the
3130 one we already had. */
3131 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3135 tmpl = build_template_decl (decl, current_template_parms,
3139 if (DECL_LANG_SPECIFIC (decl)
3140 && DECL_TEMPLATE_SPECIALIZATION (decl))
3142 /* A specialization of a member template of a template
3144 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3145 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3146 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3152 tree a, t, current, parms;
3155 if (TREE_CODE (decl) == TYPE_DECL)
3157 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3158 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3159 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3160 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3161 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3164 error ("%qD does not declare a template type", decl);
3168 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3170 error ("template definition of non-template %q#D", decl);
3174 tmpl = DECL_TI_TEMPLATE (decl);
3176 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3177 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3178 && DECL_TEMPLATE_SPECIALIZATION (decl)
3179 && DECL_MEMBER_TEMPLATE_P (tmpl))
3183 /* The declaration is a specialization of a member
3184 template, declared outside the class. Therefore, the
3185 innermost template arguments will be NULL, so we
3186 replace them with the arguments determined by the
3187 earlier call to check_explicit_specialization. */
3188 args = DECL_TI_ARGS (decl);
3191 = build_template_decl (decl, current_template_parms,
3193 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3194 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3195 DECL_TI_TEMPLATE (decl) = new_tmpl;
3196 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3197 DECL_TEMPLATE_INFO (new_tmpl)
3198 = tree_cons (tmpl, args, NULL_TREE);
3200 register_specialization (new_tmpl,
3201 most_general_template (tmpl),
3207 /* Make sure the template headers we got make sense. */
3209 parms = DECL_TEMPLATE_PARMS (tmpl);
3210 i = TMPL_PARMS_DEPTH (parms);
3211 if (TMPL_ARGS_DEPTH (args) != i)
3213 error ("expected %d levels of template parms for %q#D, got %d",
3214 i, decl, TMPL_ARGS_DEPTH (args));
3217 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3219 a = TMPL_ARGS_LEVEL (args, i);
3220 t = INNERMOST_TEMPLATE_PARMS (parms);
3222 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3224 if (current == decl)
3225 error ("got %d template parameters for %q#D",
3226 TREE_VEC_LENGTH (a), decl);
3228 error ("got %d template parameters for %q#T",
3229 TREE_VEC_LENGTH (a), current);
3230 error (" but %d required", TREE_VEC_LENGTH (t));
3231 return error_mark_node;
3234 /* Perhaps we should also check that the parms are used in the
3235 appropriate qualifying scopes in the declarator? */
3237 if (current == decl)
3240 current = TYPE_CONTEXT (current);
3244 DECL_TEMPLATE_RESULT (tmpl) = decl;
3245 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3247 /* Push template declarations for global functions and types. Note
3248 that we do not try to push a global template friend declared in a
3249 template class; such a thing may well depend on the template
3250 parameters of the class. */
3251 if (new_template_p && !ctx
3252 && !(is_friend && template_class_depth (current_class_type) > 0))
3254 tmpl = pushdecl_namespace_level (tmpl, is_friend);
3255 if (tmpl == error_mark_node)
3256 return error_mark_node;
3258 /* Hide template friend classes that haven't been declared yet. */
3259 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
3261 DECL_ANTICIPATED (tmpl) = 1;
3262 DECL_FRIEND_P (tmpl) = 1;
3268 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3269 if (DECL_CONV_FN_P (tmpl))
3271 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3273 /* It is a conversion operator. See if the type converted to
3274 depends on innermost template operands. */
3276 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3278 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3282 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3283 back to its most general template. If TMPL is a specialization,
3284 ARGS may only have the innermost set of arguments. Add the missing
3285 argument levels if necessary. */
3286 if (DECL_TEMPLATE_INFO (tmpl))
3287 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3289 info = tree_cons (tmpl, args, NULL_TREE);
3291 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3293 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3294 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3295 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3296 /* Don't change the name if we've already set it up. */
3297 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3298 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3300 else if (DECL_LANG_SPECIFIC (decl))
3301 DECL_TEMPLATE_INFO (decl) = info;
3303 return DECL_TEMPLATE_RESULT (tmpl);
3307 push_template_decl (tree decl)
3309 return push_template_decl_real (decl, false);
3312 /* Called when a class template TYPE is redeclared with the indicated
3313 template PARMS, e.g.:
3315 template <class T> struct S;
3316 template <class T> struct S {}; */
3319 redeclare_class_template (tree type, tree parms)
3325 if (!TYPE_TEMPLATE_INFO (type))
3327 error ("%qT is not a template type", type);
3331 tmpl = TYPE_TI_TEMPLATE (type);
3332 if (!PRIMARY_TEMPLATE_P (tmpl))
3333 /* The type is nested in some template class. Nothing to worry
3334 about here; there are no new template parameters for the nested
3340 error ("template specifiers not specified in declaration of %qD",
3345 parms = INNERMOST_TEMPLATE_PARMS (parms);
3346 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3348 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3350 error ("previous declaration %q+D", tmpl);
3351 error ("used %d template parameter(s) instead of %d",
3352 TREE_VEC_LENGTH (tmpl_parms),
3353 TREE_VEC_LENGTH (parms));
3357 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3364 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
3365 || TREE_VEC_ELT (parms, i) == error_mark_node)
3368 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3369 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3370 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3371 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3373 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3375 if (tmpl_parm != error_mark_node
3376 && (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3377 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3378 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))))
3380 error ("template parameter %q+#D", tmpl_parm);
3381 error ("redeclared here as %q#D", parm);
3385 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3387 /* We have in [temp.param]:
3389 A template-parameter may not be given default arguments
3390 by two different declarations in the same scope. */
3391 error ("redefinition of default argument for %q#D", parm);
3392 error ("%J original definition appeared here", tmpl_parm);
3396 if (parm_default != NULL_TREE)
3397 /* Update the previous template parameters (which are the ones
3398 that will really count) with the new default value. */
3399 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3400 else if (tmpl_default != NULL_TREE)
3401 /* Update the new parameters, too; they'll be used as the
3402 parameters for any members. */
3403 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3407 /* Simplify EXPR if it is a non-dependent expression. Returns the
3408 (possibly simplified) expression. */
3411 fold_non_dependent_expr (tree expr)
3413 /* If we're in a template, but EXPR isn't value dependent, simplify
3414 it. We're supposed to treat:
3416 template <typename T> void f(T[1 + 1]);
3417 template <typename T> void f(T[2]);
3419 as two declarations of the same function, for example. */
3420 if (processing_template_decl
3421 && !type_dependent_expression_p (expr)
3422 && !value_dependent_expression_p (expr))
3424 HOST_WIDE_INT saved_processing_template_decl;
3426 saved_processing_template_decl = processing_template_decl;
3427 processing_template_decl = 0;
3428 expr = tsubst_copy_and_build (expr,
3431 /*in_decl=*/NULL_TREE,
3432 /*function_p=*/false,
3433 /*integral_constant_expression_p=*/true);
3434 processing_template_decl = saved_processing_template_decl;
3439 /* EXPR is an expression which is used in a constant-expression context.
3440 For instance, it could be a VAR_DECL with a constant initializer.
3441 Extract the innest constant expression.
3443 This is basically a more powerful version of
3444 integral_constant_value, which can be used also in templates where
3445 initializers can maintain a syntactic rather than semantic form
3446 (even if they are non-dependent, for access-checking purposes). */
3449 fold_decl_constant_value (tree expr)
3451 tree const_expr = expr;
3454 expr = fold_non_dependent_expr (const_expr);
3455 const_expr = integral_constant_value (expr);
3457 while (expr != const_expr);
3462 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3463 must be a function or a pointer-to-function type, as specified
3464 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3465 and check that the resulting function has external linkage. */
3468 convert_nontype_argument_function (tree type, tree expr)
3473 fn = instantiate_type (type, fns, tf_none);
3474 if (fn == error_mark_node)
3475 return error_mark_node;
3478 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3479 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3480 if (TREE_CODE (fn_no_ptr) == BASELINK)
3481 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
3483 /* [temp.arg.nontype]/1
3485 A template-argument for a non-type, non-template template-parameter
3488 -- the address of an object or function with external linkage. */
3489 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3491 error ("%qE is not a valid template argument for type %qT "
3492 "because function %qD has not external linkage",
3493 expr, type, fn_no_ptr);
3500 /* Attempt to convert the non-type template parameter EXPR to the
3501 indicated TYPE. If the conversion is successful, return the
3502 converted value. If the conversion is unsuccessful, return
3503 NULL_TREE if we issued an error message, or error_mark_node if we
3504 did not. We issue error messages for out-and-out bad template
3505 parameters, but not simply because the conversion failed, since we
3506 might be just trying to do argument deduction. Both TYPE and EXPR
3507 must be non-dependent.
3509 The conversion follows the special rules described in
3510 [temp.arg.nontype], and it is much more strict than an implicit
3513 This function is called twice for each template argument (see
3514 lookup_template_class for a more accurate description of this
3515 problem). This means that we need to handle expressions which
3516 are not valid in a C++ source, but can be created from the
3517 first call (for instance, casts to perform conversions). These
3518 hacks can go away after we fix the double coercion problem. */
3521 convert_nontype_argument (tree type, tree expr)
3525 /* Detect immediately string literals as invalid non-type argument.
3526 This special-case is not needed for correctness (we would easily
3527 catch this later), but only to provide better diagnostic for this
3528 common user mistake. As suggested by DR 100, we do not mention
3529 linkage issues in the diagnostic as this is not the point. */
3530 if (TREE_CODE (expr) == STRING_CST)
3532 error ("%qE is not a valid template argument for type %qT "
3533 "because string literals can never be used in this context",
3538 /* If we are in a template, EXPR may be non-dependent, but still
3539 have a syntactic, rather than semantic, form. For example, EXPR
3540 might be a SCOPE_REF, rather than the VAR_DECL to which the
3541 SCOPE_REF refers. Preserving the qualifying scope is necessary
3542 so that access checking can be performed when the template is
3543 instantiated -- but here we need the resolved form so that we can
3544 convert the argument. */
3545 expr = fold_non_dependent_expr (expr);
3546 if (error_operand_p (expr))
3547 return error_mark_node;
3548 expr_type = TREE_TYPE (expr);
3550 /* HACK: Due to double coercion, we can get a
3551 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3552 which is the tree that we built on the first call (see
3553 below when coercing to reference to object or to reference to
3554 function). We just strip everything and get to the arg.
3555 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3557 if (TREE_CODE (expr) == NOP_EXPR)
3559 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3561 /* ??? Maybe we could use convert_from_reference here, but we
3562 would need to relax its constraints because the NOP_EXPR
3563 could actually change the type to something more cv-qualified,
3564 and this is not folded by convert_from_reference. */
3565 tree addr = TREE_OPERAND (expr, 0);
3566 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3567 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3568 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3569 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3570 (TREE_TYPE (expr_type),
3571 TREE_TYPE (TREE_TYPE (addr))));
3573 expr = TREE_OPERAND (addr, 0);
3574 expr_type = TREE_TYPE (expr);
3577 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3578 parameter is a pointer to object, through decay and
3579 qualification conversion. Let's strip everything. */
3580 else if (TYPE_PTROBV_P (type))
3583 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3584 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3585 /* Skip the ADDR_EXPR only if it is part of the decay for
3586 an array. Otherwise, it is part of the original argument
3587 in the source code. */
3588 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3589 expr = TREE_OPERAND (expr, 0);
3590 expr_type = TREE_TYPE (expr);
3594 /* [temp.arg.nontype]/5, bullet 1
3596 For a non-type template-parameter of integral or enumeration type,
3597 integral promotions (_conv.prom_) and integral conversions
3598 (_conv.integral_) are applied. */
3599 if (INTEGRAL_TYPE_P (type))
3601 if (!INTEGRAL_TYPE_P (expr_type))
3602 return error_mark_node;
3604 expr = fold_decl_constant_value (expr);
3605 /* Notice that there are constant expressions like '4 % 0' which
3606 do not fold into integer constants. */
3607 if (TREE_CODE (expr) != INTEGER_CST)
3609 error ("%qE is not a valid template argument for type %qT "
3610 "because it is a non-constant expression", expr, type);
3614 /* At this point, an implicit conversion does what we want,
3615 because we already know that the expression is of integral
3617 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3618 if (expr == error_mark_node)
3619 return error_mark_node;
3621 /* Conversion was allowed: fold it to a bare integer constant. */
3624 /* [temp.arg.nontype]/5, bullet 2
3626 For a non-type template-parameter of type pointer to object,
3627 qualification conversions (_conv.qual_) and the array-to-pointer
3628 conversion (_conv.array_) are applied. */
3629 else if (TYPE_PTROBV_P (type))
3631 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3633 A template-argument for a non-type, non-template template-parameter
3634 shall be one of: [...]
3636 -- the name of a non-type template-parameter;
3637 -- the address of an object or function with external linkage, [...]
3638 expressed as "& id-expression" where the & is optional if the name
3639 refers to a function or array, or if the corresponding
3640 template-parameter is a reference.
3642 Here, we do not care about functions, as they are invalid anyway
3643 for a parameter of type pointer-to-object. */
3644 bool constant_address_p =
3645 (TREE_CODE (expr) == ADDR_EXPR
3646 || TREE_CODE (expr_type) == ARRAY_TYPE
3647 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3649 expr = decay_conversion (expr);
3650 if (expr == error_mark_node)
3651 return error_mark_node;
3653 expr = perform_qualification_conversions (type, expr);
3654 if (expr == error_mark_node)
3655 return error_mark_node;
3657 if (!constant_address_p)
3659 error ("%qE is not a valid template argument for type %qT "
3660 "because it is not a constant pointer", expr, type);
3664 /* [temp.arg.nontype]/5, bullet 3
3666 For a non-type template-parameter of type reference to object, no
3667 conversions apply. The type referred to by the reference may be more
3668 cv-qualified than the (otherwise identical) type of the
3669 template-argument. The template-parameter is bound directly to the
3670 template-argument, which must be an lvalue. */
3671 else if (TYPE_REF_OBJ_P (type))
3673 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3675 return error_mark_node;
3677 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3679 error ("%qE is not a valid template argument for type %qT "
3680 "because of conflicts in cv-qualification", expr, type);
3684 if (!real_lvalue_p (expr))
3686 error ("%qE is not a valid template argument for type %qT "
3687 "because it is not an lvalue", expr, type);
3691 /* [temp.arg.nontype]/1
3693 A template-argument for a non-type, non-template template-parameter
3694 shall be one of: [...]
3696 -- the address of an object or function with external linkage. */
3697 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3699 error ("%qE is not a valid template argument for type %qT "
3700 "because object %qD has not external linkage",
3705 expr = build_nop (type, build_address (expr));
3707 /* [temp.arg.nontype]/5, bullet 4
3709 For a non-type template-parameter of type pointer to function, only
3710 the function-to-pointer conversion (_conv.func_) is applied. If the
3711 template-argument represents a set of overloaded functions (or a
3712 pointer to such), the matching function is selected from the set
3714 else if (TYPE_PTRFN_P (type))
3716 /* If the argument is a template-id, we might not have enough
3717 context information to decay the pointer. */
3718 if (!type_unknown_p (expr_type))
3720 expr = decay_conversion (expr);
3721 if (expr == error_mark_node)
3722 return error_mark_node;
3725 expr = convert_nontype_argument_function (type, expr);
3726 if (!expr || expr == error_mark_node)
3729 /* [temp.arg.nontype]/5, bullet 5
3731 For a non-type template-parameter of type reference to function, no
3732 conversions apply. If the template-argument represents a set of
3733 overloaded functions, the matching function is selected from the set
3735 else if (TYPE_REFFN_P (type))
3737 if (TREE_CODE (expr) == ADDR_EXPR)
3739 error ("%qE is not a valid template argument for type %qT "
3740 "because it is a pointer", expr, type);
3741 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3745 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3746 if (!expr || expr == error_mark_node)
3749 expr = build_nop (type, build_address (expr));
3751 /* [temp.arg.nontype]/5, bullet 6
3753 For a non-type template-parameter of type pointer to member function,
3754 no conversions apply. If the template-argument represents a set of
3755 overloaded member functions, the matching member function is selected
3756 from the set (_over.over_). */
3757 else if (TYPE_PTRMEMFUNC_P (type))
3759 expr = instantiate_type (type, expr, tf_none);
3760 if (expr == error_mark_node)
3761 return error_mark_node;
3763 /* There is no way to disable standard conversions in
3764 resolve_address_of_overloaded_function (called by
3765 instantiate_type). It is possible that the call succeeded by
3766 converting &B::I to &D::I (where B is a base of D), so we need
3767 to reject this conversion here.
3769 Actually, even if there was a way to disable standard conversions,
3770 it would still be better to reject them here so that we can
3771 provide a superior diagnostic. */
3772 if (!same_type_p (TREE_TYPE (expr), type))
3774 /* Make sure we are just one standard conversion off. */
3775 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3776 error ("%qE is not a valid template argument for type %qT "
3777 "because it is of type %qT", expr, type,
3779 inform ("standard conversions are not allowed in this context");
3783 /* [temp.arg.nontype]/5, bullet 7
3785 For a non-type template-parameter of type pointer to data member,
3786 qualification conversions (_conv.qual_) are applied. */
3787 else if (TYPE_PTRMEM_P (type))
3789 expr = perform_qualification_conversions (type, expr);
3790 if (expr == error_mark_node)
3793 /* A template non-type parameter must be one of the above. */
3797 /* Sanity check: did we actually convert the argument to the
3799 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3804 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3805 template template parameters. Both PARM_PARMS and ARG_PARMS are
3806 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3809 Consider the example:
3810 template <class T> class A;
3811 template<template <class U> class TT> class B;
3813 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
3814 the parameters to A, and OUTER_ARGS contains A. */
3817 coerce_template_template_parms (tree parm_parms,
3819 tsubst_flags_t complain,
3823 int nparms, nargs, i;
3826 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3827 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3829 nparms = TREE_VEC_LENGTH (parm_parms);
3830 nargs = TREE_VEC_LENGTH (arg_parms);
3832 if (nargs != nparms)
3835 for (i = 0; i < nparms; ++i)
3837 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
3838 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
3841 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3842 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3844 if (arg == NULL_TREE || arg == error_mark_node
3845 || parm == NULL_TREE || parm == error_mark_node)
3848 if (TREE_CODE (arg) != TREE_CODE (parm))
3851 switch (TREE_CODE (parm))
3857 /* We encounter instantiations of templates like
3858 template <template <template <class> class> class TT>
3861 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3862 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3864 if (!coerce_template_template_parms
3865 (parmparm, argparm, complain, in_decl, outer_args))
3871 /* The tsubst call is used to handle cases such as
3873 template <int> class C {};
3874 template <class T, template <T> class TT> class D {};
3877 i.e. the parameter list of TT depends on earlier parameters. */
3878 if (!dependent_type_p (TREE_TYPE (arg))
3880 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3892 /* Convert the indicated template ARG as necessary to match the
3893 indicated template PARM. Returns the converted ARG, or
3894 error_mark_node if the conversion was unsuccessful. Error and
3895 warning messages are issued under control of COMPLAIN. This
3896 conversion is for the Ith parameter in the parameter list. ARGS is
3897 the full set of template arguments deduced so far. */
3900 convert_template_argument (tree parm,
3903 tsubst_flags_t complain,
3908 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3910 if (TREE_CODE (arg) == TREE_LIST
3911 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3913 /* The template argument was the name of some
3914 member function. That's usually
3915 invalid, but static members are OK. In any
3916 case, grab the underlying fields/functions
3917 and issue an error later if required. */
3918 arg = TREE_VALUE (arg);
3919 TREE_TYPE (arg) = unknown_type_node;
3922 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3923 requires_type = (TREE_CODE (parm) == TYPE_DECL
3924 || requires_tmpl_type);
3926 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3927 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3928 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3929 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3932 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3933 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3934 arg = TYPE_STUB_DECL (arg);
3936 is_type = TYPE_P (arg) || is_tmpl_type;
3938 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3939 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3941 pedwarn ("to refer to a type member of a template parameter, "
3942 "use %<typename %E%>", arg);
3944 arg = make_typename_type (TREE_OPERAND (arg, 0),
3945 TREE_OPERAND (arg, 1),
3947 complain & tf_error);
3950 if (is_type != requires_type)
3954 if (complain & tf_error)
3956 error ("type/value mismatch at argument %d in template "
3957 "parameter list for %qD",
3960 error (" expected a constant of type %qT, got %qT",
3962 (is_tmpl_type ? DECL_NAME (arg) : arg));
3963 else if (requires_tmpl_type)
3964 error (" expected a class template, got %qE", arg);
3966 error (" expected a type, got %qE", arg);
3969 return error_mark_node;
3971 if (is_tmpl_type ^ requires_tmpl_type)
3973 if (in_decl && (complain & tf_error))
3975 error ("type/value mismatch at argument %d in template "
3976 "parameter list for %qD",
3979 error (" expected a type, got %qT", DECL_NAME (arg));
3981 error (" expected a class template, got %qT", arg);
3983 return error_mark_node;
3988 if (requires_tmpl_type)
3990 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3991 /* The number of argument required is not known yet.
3992 Just accept it for now. */
3993 val = TREE_TYPE (arg);
3996 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3997 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3999 if (coerce_template_template_parms (parmparm, argparm,
4005 /* TEMPLATE_TEMPLATE_PARM node is preferred over
4007 if (val != error_mark_node
4008 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
4009 val = TREE_TYPE (val);
4013 if (in_decl && (complain & tf_error))
4015 error ("type/value mismatch at argument %d in "
4016 "template parameter list for %qD",
4018 error (" expected a template of type %qD, got %qD",
4022 val = error_mark_node;
4028 /* We only form one instance of each template specialization.
4029 Therefore, if we use a non-canonical variant (i.e., a
4030 typedef), any future messages referring to the type will use
4031 the typedef, which is confusing if those future uses do not
4032 themselves also use the typedef. */
4034 val = canonical_type_variant (val);
4038 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
4040 if (invalid_nontype_parm_type_p (t, complain))
4041 return error_mark_node;
4043 if (!uses_template_parms (arg) && !uses_template_parms (t))
4044 /* We used to call digest_init here. However, digest_init
4045 will report errors, which we don't want when complain
4046 is zero. More importantly, digest_init will try too
4047 hard to convert things: for example, `0' should not be
4048 converted to pointer type at this point according to
4049 the standard. Accepting this is not merely an
4050 extension, since deciding whether or not these
4051 conversions can occur is part of determining which
4052 function template to call, or whether a given explicit
4053 argument specification is valid. */
4054 val = convert_nontype_argument (t, arg);
4058 if (val == NULL_TREE)
4059 val = error_mark_node;
4060 else if (val == error_mark_node && (complain & tf_error))
4061 error ("could not convert template argument %qE to %qT", arg, t);
4067 /* Convert all template arguments to their appropriate types, and
4068 return a vector containing the innermost resulting template
4069 arguments. If any error occurs, return error_mark_node. Error and
4070 warning messages are issued under control of COMPLAIN.
4072 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
4073 for arguments not specified in ARGS. Otherwise, if
4074 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
4075 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
4076 USE_DEFAULT_ARGS is false, then all arguments must be specified in
4080 coerce_template_parms (tree parms,
4083 tsubst_flags_t complain,
4084 bool require_all_args,
4085 bool use_default_args)
4087 int nparms, nargs, i, lost = 0;
4090 tree new_inner_args;
4092 inner_args = INNERMOST_TEMPLATE_ARGS (args);
4093 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
4094 nparms = TREE_VEC_LENGTH (parms);
4099 && (!use_default_args
4100 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
4101 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
4103 if (complain & tf_error)
4105 error ("wrong number of template arguments (%d, should be %d)",
4109 error ("provided for %q+D", in_decl);
4112 return error_mark_node;
4115 new_inner_args = make_tree_vec (nparms);
4116 new_args = add_outermost_template_args (args, new_inner_args);
4117 for (i = 0; i < nparms; i++)
4122 /* Get the Ith template parameter. */
4123 parm = TREE_VEC_ELT (parms, i);
4125 if (parm == error_mark_node)
4127 TREE_VEC_ELT (new_inner_args, i) = error_mark_node;
4131 /* Calculate the Ith argument. */
4133 arg = TREE_VEC_ELT (inner_args, i);
4134 else if (require_all_args)
4135 /* There must be a default arg in this case. */
4136 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4142 if (arg == error_mark_node)
4144 if (complain & tf_error)
4145 error ("template argument %d is invalid", i + 1);
4148 arg = convert_template_argument (TREE_VALUE (parm),
4149 arg, new_args, complain, i,
4152 if (arg == error_mark_node)
4154 TREE_VEC_ELT (new_inner_args, i) = arg;
4158 return error_mark_node;
4160 return new_inner_args;
4163 /* Returns 1 if template args OT and NT are equivalent. */
4166 template_args_equal (tree ot, tree nt)
4171 if (TREE_CODE (nt) == TREE_VEC)
4172 /* For member templates */
4173 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4174 else if (TYPE_P (nt))
4175 return TYPE_P (ot) && same_type_p (ot, nt);
4176 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4179 return cp_tree_equal (ot, nt);
4182 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4183 of template arguments. Returns 0 otherwise. */
4186 comp_template_args (tree oldargs, tree newargs)
4190 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4193 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4195 tree nt = TREE_VEC_ELT (newargs, i);
4196 tree ot = TREE_VEC_ELT (oldargs, i);
4198 if (! template_args_equal (ot, nt))
4204 /* Given class template name and parameter list, produce a user-friendly name
4205 for the instantiation. */
4208 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4210 static struct obstack scratch_obstack;
4211 static char *scratch_firstobj;
4214 if (!scratch_firstobj)
4215 gcc_obstack_init (&scratch_obstack);
4217 obstack_free (&scratch_obstack, scratch_firstobj);
4218 scratch_firstobj = (char *) obstack_alloc (&scratch_obstack, 1);
4220 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4221 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4225 nparms = TREE_VEC_LENGTH (parms);
4226 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4227 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4228 for (i = 0; i < nparms; i++)
4233 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4234 arg = TREE_VEC_ELT (arglist, i);
4236 if (parm == error_mark_node)
4242 if (TREE_CODE (parm) == TYPE_DECL)
4244 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4247 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4249 if (TREE_CODE (arg) == TEMPLATE_DECL)
4251 /* Already substituted with real template. Just output
4252 the template name here */
4253 tree context = DECL_CONTEXT (arg);
4256 /* The template may be defined in a namespace, or
4257 may be a member template. */
4258 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4259 || CLASS_TYPE_P (context));
4260 cat (decl_as_string (DECL_CONTEXT (arg),
4261 TFF_PLAIN_IDENTIFIER));
4264 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4267 /* Output the parameter declaration. */
4268 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4272 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4274 /* No need to check arglist against parmlist here; we did that
4275 in coerce_template_parms, called from lookup_template_class. */
4276 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4279 char *bufp = obstack_next_free (&scratch_obstack);
4281 while (bufp[offset - 1] == ' ')
4283 obstack_blank_fast (&scratch_obstack, offset);
4285 /* B<C<char> >, not B<C<char>> */
4286 if (bufp[offset - 1] == '>')
4291 return (char *) obstack_base (&scratch_obstack);
4295 classtype_mangled_name (tree t)
4297 if (CLASSTYPE_TEMPLATE_INFO (t)
4298 /* Specializations have already had their names set up in
4299 lookup_template_class. */
4300 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4302 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4304 /* For non-primary templates, the template parameters are
4305 implicit from their surrounding context. */
4306 if (PRIMARY_TEMPLATE_P (tmpl))
4308 tree name = DECL_NAME (tmpl);
4309 char *mangled_name = mangle_class_name_for_template
4310 (IDENTIFIER_POINTER (name),
4311 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4312 CLASSTYPE_TI_ARGS (t));
4313 tree id = get_identifier (mangled_name);
4314 IDENTIFIER_TEMPLATE (id) = name;
4319 return TYPE_IDENTIFIER (t);
4323 add_pending_template (tree d)
4325 tree ti = (TYPE_P (d)
4326 ? CLASSTYPE_TEMPLATE_INFO (d)
4327 : DECL_TEMPLATE_INFO (d));
4331 if (TI_PENDING_TEMPLATE_FLAG (ti))
4334 /* We are called both from instantiate_decl, where we've already had a
4335 tinst_level pushed, and instantiate_template, where we haven't.
4337 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4340 push_tinst_level (d);
4342 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4343 if (last_pending_template)
4344 TREE_CHAIN (last_pending_template) = pt;
4346 pending_templates = pt;
4348 last_pending_template = pt;
4350 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4357 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4358 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4359 documentation for TEMPLATE_ID_EXPR. */
4362 lookup_template_function (tree fns, tree arglist)
4366 if (fns == error_mark_node || arglist == error_mark_node)
4367 return error_mark_node;
4369 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4370 gcc_assert (fns && (is_overloaded_fn (fns)
4371 || TREE_CODE (fns) == IDENTIFIER_NODE));
4373 if (BASELINK_P (fns))
4375 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4377 BASELINK_FUNCTIONS (fns),
4382 type = TREE_TYPE (fns);
4383 if (TREE_CODE (fns) == OVERLOAD || !type)
4384 type = unknown_type_node;
4386 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4389 /* Within the scope of a template class S<T>, the name S gets bound
4390 (in build_self_reference) to a TYPE_DECL for the class, not a
4391 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4392 or one of its enclosing classes, and that type is a template,
4393 return the associated TEMPLATE_DECL. Otherwise, the original
4394 DECL is returned. */
4397 maybe_get_template_decl_from_type_decl (tree decl)
4399 return (decl != NULL_TREE
4400 && TREE_CODE (decl) == TYPE_DECL
4401 && DECL_ARTIFICIAL (decl)
4402 && CLASS_TYPE_P (TREE_TYPE (decl))
4403 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4404 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4407 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4408 parameters, find the desired type.
4410 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4412 IN_DECL, if non-NULL, is the template declaration we are trying to
4415 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4416 the class we are looking up.
4418 Issue error and warning messages under control of COMPLAIN.
4420 If the template class is really a local class in a template
4421 function, then the FUNCTION_CONTEXT is the function in which it is
4424 ??? Note that this function is currently called *twice* for each
4425 template-id: the first time from the parser, while creating the
4426 incomplete type (finish_template_type), and the second type during the
4427 real instantiation (instantiate_template_class). This is surely something
4428 that we want to avoid. It also causes some problems with argument
4429 coercion (see convert_nontype_argument for more information on this). */
4432 lookup_template_class (tree d1,
4437 tsubst_flags_t complain)
4439 tree template = NULL_TREE, parmlist;
4442 timevar_push (TV_NAME_LOOKUP);
4444 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4446 tree value = innermost_non_namespace_value (d1);
4447 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4452 push_decl_namespace (context);
4453 template = lookup_name (d1);
4454 template = maybe_get_template_decl_from_type_decl (template);
4456 pop_decl_namespace ();
4459 context = DECL_CONTEXT (template);
4461 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4463 tree type = TREE_TYPE (d1);
4465 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4466 an implicit typename for the second A. Deal with it. */
4467 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4468 type = TREE_TYPE (type);
4470 if (CLASSTYPE_TEMPLATE_INFO (type))
4472 template = CLASSTYPE_TI_TEMPLATE (type);
4473 d1 = DECL_NAME (template);
4476 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4477 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4479 template = TYPE_TI_TEMPLATE (d1);
4480 d1 = DECL_NAME (template);
4482 else if (TREE_CODE (d1) == TEMPLATE_DECL
4483 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4486 d1 = DECL_NAME (template);
4487 context = DECL_CONTEXT (template);
4490 /* Issue an error message if we didn't find a template. */
4493 if (complain & tf_error)
4494 error ("%qT is not a template", d1);
4495 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4498 if (TREE_CODE (template) != TEMPLATE_DECL
4499 /* Make sure it's a user visible template, if it was named by
4501 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4502 && !PRIMARY_TEMPLATE_P (template)))
4504 if (complain & tf_error)
4506 error ("non-template type %qT used as a template", d1);
4508 error ("for template declaration %q+D", in_decl);
4510 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4513 complain &= ~tf_user;
4515 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4517 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4518 template arguments */
4523 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4525 /* Consider an example where a template template parameter declared as
4527 template <class T, class U = std::allocator<T> > class TT
4529 The template parameter level of T and U are one level larger than
4530 of TT. To proper process the default argument of U, say when an
4531 instantiation `TT<int>' is seen, we need to build the full
4532 arguments containing {int} as the innermost level. Outer levels,
4533 available when not appearing as default template argument, can be
4534 obtained from `current_template_args ()'.
4536 Suppose that TT is later substituted with std::vector. The above
4537 instantiation is `TT<int, std::allocator<T> >' with TT at
4538 level 1, and T at level 2, while the template arguments at level 1
4539 becomes {std::vector} and the inner level 2 is {int}. */
4541 if (current_template_parms)
4542 arglist = add_to_template_args (current_template_args (), arglist);
4544 arglist2 = coerce_template_parms (parmlist, arglist, template,
4546 /*require_all_args=*/true,
4547 /*use_default_args=*/true);
4548 if (arglist2 == error_mark_node
4549 || (!uses_template_parms (arglist2)
4550 && check_instantiated_args (template, arglist2, complain)))
4551 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4553 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4554 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4558 tree template_type = TREE_TYPE (template);
4561 tree found = NULL_TREE;
4564 int is_partial_instantiation;
4566 gen_tmpl = most_general_template (template);
4567 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4568 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4569 arg_depth = TMPL_ARGS_DEPTH (arglist);
4571 if (arg_depth == 1 && parm_depth > 1)
4573 /* We've been given an incomplete set of template arguments.
4576 template <class T> struct S1 {
4577 template <class U> struct S2 {};
4578 template <class U> struct S2<U*> {};
4581 we will be called with an ARGLIST of `U*', but the
4582 TEMPLATE will be `template <class T> template
4583 <class U> struct S1<T>::S2'. We must fill in the missing
4586 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4588 arg_depth = TMPL_ARGS_DEPTH (arglist);
4591 /* Now we should have enough arguments. */
4592 gcc_assert (parm_depth == arg_depth);
4594 /* From here on, we're only interested in the most general
4596 template = gen_tmpl;
4598 /* Calculate the BOUND_ARGS. These will be the args that are
4599 actually tsubst'd into the definition to create the
4603 /* We have multiple levels of arguments to coerce, at once. */
4605 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4607 tree bound_args = make_tree_vec (parm_depth);
4609 for (i = saved_depth,
4610 t = DECL_TEMPLATE_PARMS (template);
4611 i > 0 && t != NULL_TREE;
4612 --i, t = TREE_CHAIN (t))
4614 tree a = coerce_template_parms (TREE_VALUE (t),
4617 /*require_all_args=*/true,
4618 /*use_default_args=*/true);
4620 /* Don't process further if one of the levels fails. */
4621 if (a == error_mark_node)
4623 /* Restore the ARGLIST to its full size. */
4624 TREE_VEC_LENGTH (arglist) = saved_depth;
4625 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4628 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4630 /* We temporarily reduce the length of the ARGLIST so
4631 that coerce_template_parms will see only the arguments
4632 corresponding to the template parameters it is
4634 TREE_VEC_LENGTH (arglist)--;
4637 /* Restore the ARGLIST to its full size. */
4638 TREE_VEC_LENGTH (arglist) = saved_depth;
4640 arglist = bound_args;
4644 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4645 INNERMOST_TEMPLATE_ARGS (arglist),
4648 /*require_all_args=*/true,
4649 /*use_default_args=*/true);
4651 if (arglist == error_mark_node)
4652 /* We were unable to bind the arguments. */
4653 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4655 /* In the scope of a template class, explicit references to the
4656 template class refer to the type of the template, not any
4657 instantiation of it. For example, in:
4659 template <class T> class C { void f(C<T>); }
4661 the `C<T>' is just the same as `C'. Outside of the
4662 class, however, such a reference is an instantiation. */
4663 if (comp_template_args (TYPE_TI_ARGS (template_type),
4666 found = template_type;
4668 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4672 for (ctx = current_class_type;
4673 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4675 ? TYPE_CONTEXT (ctx)
4676 : DECL_CONTEXT (ctx)))
4677 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4680 /* We're not in the scope of the class, so the
4681 TEMPLATE_TYPE is not the type we want after all. */
4687 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4689 /* If we already have this specialization, return it. */
4690 found = retrieve_specialization (template, arglist,
4691 /*class_specializations_p=*/false);
4693 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4695 /* This type is a "partial instantiation" if any of the template
4696 arguments still involve template parameters. Note that we set
4697 IS_PARTIAL_INSTANTIATION for partial specializations as
4699 is_partial_instantiation = uses_template_parms (arglist);
4701 /* If the deduced arguments are invalid, then the binding
4703 if (!is_partial_instantiation
4704 && check_instantiated_args (template,
4705 INNERMOST_TEMPLATE_ARGS (arglist),
4707 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4709 if (!is_partial_instantiation
4710 && !PRIMARY_TEMPLATE_P (template)
4711 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4713 found = xref_tag_from_type (TREE_TYPE (template),
4714 DECL_NAME (template),
4715 /*tag_scope=*/ts_global);
4716 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4719 context = tsubst (DECL_CONTEXT (template), arglist,
4722 context = global_namespace;
4724 /* Create the type. */
4725 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4727 if (!is_partial_instantiation)
4729 set_current_access_from_decl (TYPE_NAME (template_type));
4730 t = start_enum (TYPE_IDENTIFIER (template_type));
4733 /* We don't want to call start_enum for this type, since
4734 the values for the enumeration constants may involve
4735 template parameters. And, no one should be interested
4736 in the enumeration constants for such a type. */
4737 t = make_node (ENUMERAL_TYPE);
4741 t = make_aggr_type (TREE_CODE (template_type));
4742 CLASSTYPE_DECLARED_CLASS (t)
4743 = CLASSTYPE_DECLARED_CLASS (template_type);
4744 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4745 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4747 /* A local class. Make sure the decl gets registered properly. */
4748 if (context == current_function_decl)
4749 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
4752 /* If we called start_enum or pushtag above, this information
4753 will already be set up. */
4756 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4758 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4759 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4760 TYPE_STUB_DECL (t) = type_decl;
4761 DECL_SOURCE_LOCATION (type_decl)
4762 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4765 type_decl = TYPE_NAME (t);
4767 TREE_PRIVATE (type_decl)
4768 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4769 TREE_PROTECTED (type_decl)
4770 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4771 DECL_IN_SYSTEM_HEADER (type_decl)
4772 = DECL_IN_SYSTEM_HEADER (template);
4773 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
4775 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
4776 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
4779 /* Set up the template information. We have to figure out which
4780 template is the immediate parent if this is a full
4782 if (parm_depth == 1 || is_partial_instantiation
4783 || !PRIMARY_TEMPLATE_P (template))
4784 /* This case is easy; there are no member templates involved. */
4788 /* This is a full instantiation of a member template. Look
4789 for a partial instantiation of which this is an instance. */
4791 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4792 found; found = TREE_CHAIN (found))
4795 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4797 /* We only want partial instantiations, here, not
4798 specializations or full instantiations. */
4799 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4800 || !uses_template_parms (TREE_VALUE (found)))
4803 /* Temporarily reduce by one the number of levels in the
4804 ARGLIST and in FOUND so as to avoid comparing the
4805 last set of arguments. */
4806 TREE_VEC_LENGTH (arglist)--;
4807 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4809 /* See if the arguments match. If they do, then TMPL is
4810 the partial instantiation we want. */
4811 success = comp_template_args (TREE_PURPOSE (found), arglist);
4813 /* Restore the argument vectors to their full size. */
4814 TREE_VEC_LENGTH (arglist)++;
4815 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4826 /* There was no partial instantiation. This happens
4827 where C<T> is a member template of A<T> and it's used
4830 template <typename T> struct B { A<T>::C<int> m; };
4833 Create the partial instantiation.
4835 TREE_VEC_LENGTH (arglist)--;
4836 found = tsubst (template, arglist, complain, NULL_TREE);
4837 TREE_VEC_LENGTH (arglist)++;
4841 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4842 DECL_TEMPLATE_INSTANTIATIONS (template)
4843 = tree_cons (arglist, t,
4844 DECL_TEMPLATE_INSTANTIATIONS (template));
4846 if (TREE_CODE (t) == ENUMERAL_TYPE
4847 && !is_partial_instantiation)
4848 /* Now that the type has been registered on the instantiations
4849 list, we set up the enumerators. Because the enumeration
4850 constants may involve the enumeration type itself, we make
4851 sure to register the type first, and then create the
4852 constants. That way, doing tsubst_expr for the enumeration
4853 constants won't result in recursive calls here; we'll find
4854 the instantiation and exit above. */
4855 tsubst_enum (template_type, t, arglist);
4857 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4859 if (TREE_CODE (t) != ENUMERAL_TYPE)
4860 DECL_NAME (type_decl) = classtype_mangled_name (t);
4861 if (is_partial_instantiation)
4862 /* If the type makes use of template parameters, the
4863 code that generates debugging information will crash. */
4864 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4866 /* Possibly limit visibility based on template args. */
4867 TREE_PUBLIC (type_decl) = 1;
4868 determine_visibility (type_decl);
4870 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4872 timevar_pop (TV_NAME_LOOKUP);
4879 struct pointer_set_t *visited;
4882 /* Called from for_each_template_parm via walk_tree. */
4885 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4888 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4889 tree_fn_t fn = pfd->fn;
4890 void *data = pfd->data;
4893 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4894 return error_mark_node;
4896 switch (TREE_CODE (t))
4899 if (TYPE_PTRMEMFUNC_P (t))
4905 if (!TYPE_TEMPLATE_INFO (t))
4907 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4908 fn, data, pfd->visited))
4909 return error_mark_node;
4913 /* Since we're not going to walk subtrees, we have to do this
4915 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4917 return error_mark_node;
4921 /* Check the return type. */
4922 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4923 return error_mark_node;
4925 /* Check the parameter types. Since default arguments are not
4926 instantiated until they are needed, the TYPE_ARG_TYPES may
4927 contain expressions that involve template parameters. But,
4928 no-one should be looking at them yet. And, once they're
4929 instantiated, they don't contain template parameters, so
4930 there's no point in looking at them then, either. */
4934 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4935 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4937 return error_mark_node;
4939 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4940 want walk_tree walking into them itself. */
4946 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4948 return error_mark_node;
4953 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4954 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4956 return error_mark_node;
4961 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4962 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4964 return error_mark_node;
4965 if (DECL_CONTEXT (t)
4966 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4968 return error_mark_node;
4971 case BOUND_TEMPLATE_TEMPLATE_PARM:
4972 /* Record template parameters such as `T' inside `TT<T>'. */
4973 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4974 return error_mark_node;
4977 case TEMPLATE_TEMPLATE_PARM:
4978 case TEMPLATE_TYPE_PARM:
4979 case TEMPLATE_PARM_INDEX:
4980 if (fn && (*fn)(t, data))
4981 return error_mark_node;
4983 return error_mark_node;
4987 /* A template template parameter is encountered. */
4988 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4989 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4990 return error_mark_node;
4992 /* Already substituted template template parameter */
4998 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4999 data, pfd->visited))
5000 return error_mark_node;
5004 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
5005 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
5006 (TREE_TYPE (t)), fn, data,
5008 return error_mark_node;
5013 /* If there's no type, then this thing must be some expression
5014 involving template parameters. */
5015 if (!fn && !TREE_TYPE (t))
5016 return error_mark_node;
5021 case REINTERPRET_CAST_EXPR:
5022 case CONST_CAST_EXPR:
5023 case STATIC_CAST_EXPR:
5024 case DYNAMIC_CAST_EXPR:
5028 case PSEUDO_DTOR_EXPR:
5030 return error_mark_node;
5034 /* If we do not handle this case specially, we end up walking
5035 the BINFO hierarchy, which is circular, and therefore
5036 confuses walk_tree. */
5038 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
5040 return error_mark_node;
5047 /* We didn't find any template parameters we liked. */
5051 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
5052 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
5053 call FN with the parameter and the DATA.
5054 If FN returns nonzero, the iteration is terminated, and
5055 for_each_template_parm returns 1. Otherwise, the iteration
5056 continues. If FN never returns a nonzero value, the value
5057 returned by for_each_template_parm is 0. If FN is NULL, it is
5058 considered to be the function which always returns 1. */
5061 for_each_template_parm (tree t, tree_fn_t fn, void* data,
5062 struct pointer_set_t *visited)
5064 struct pair_fn_data pfd;
5071 /* Walk the tree. (Conceptually, we would like to walk without
5072 duplicates, but for_each_template_parm_r recursively calls
5073 for_each_template_parm, so we would need to reorganize a fair
5074 bit to use walk_tree_without_duplicates, so we keep our own
5077 pfd.visited = visited;
5079 pfd.visited = pointer_set_create ();
5080 result = walk_tree (&t,
5081 for_each_template_parm_r,
5083 pfd.visited) != NULL_TREE;
5088 pointer_set_destroy (pfd.visited);
5095 /* Returns true if T depends on any template parameter. */
5098 uses_template_parms (tree t)
5101 int saved_processing_template_decl;
5103 saved_processing_template_decl = processing_template_decl;
5104 if (!saved_processing_template_decl)
5105 processing_template_decl = 1;
5107 dependent_p = dependent_type_p (t);
5108 else if (TREE_CODE (t) == TREE_VEC)
5109 dependent_p = any_dependent_template_arguments_p (t);
5110 else if (TREE_CODE (t) == TREE_LIST)
5111 dependent_p = (uses_template_parms (TREE_VALUE (t))
5112 || uses_template_parms (TREE_CHAIN (t)));
5113 else if (TREE_CODE (t) == TYPE_DECL)
5114 dependent_p = dependent_type_p (TREE_TYPE (t));
5117 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
5118 || TREE_CODE (t) == OVERLOAD
5119 || TREE_CODE (t) == BASELINK
5120 || TREE_CODE (t) == IDENTIFIER_NODE
5121 || CONSTANT_CLASS_P (t))
5122 dependent_p = (type_dependent_expression_p (t)
5123 || value_dependent_expression_p (t));
5126 gcc_assert (t == error_mark_node);
5127 dependent_p = false;
5130 processing_template_decl = saved_processing_template_decl;
5135 /* Returns true if T depends on any template parameter with level LEVEL. */
5138 uses_template_parms_level (tree t, int level)
5140 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
5143 static int tinst_depth;
5144 extern int max_tinst_depth;
5145 #ifdef GATHER_STATISTICS
5148 static int tinst_level_tick;
5149 static int last_template_error_tick;
5151 /* We're starting to instantiate D; record the template instantiation context
5152 for diagnostics and to restore it later. */
5155 push_tinst_level (tree d)
5159 if (tinst_depth >= max_tinst_depth)
5161 /* If the instantiation in question still has unbound template parms,
5162 we don't really care if we can't instantiate it, so just return.
5163 This happens with base instantiation for implicit `typename'. */
5164 if (uses_template_parms (d))
5167 last_template_error_tick = tinst_level_tick;
5168 error ("template instantiation depth exceeds maximum of %d (use "
5169 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5170 max_tinst_depth, d);
5172 print_instantiation_context ();
5177 new = make_node (TINST_LEVEL);
5178 TINST_DECL (new) = d;
5179 TINST_LOCATION (new) = input_location;
5180 TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
5181 TREE_CHAIN (new) = current_tinst_level;
5182 current_tinst_level = new;
5185 #ifdef GATHER_STATISTICS
5186 if (tinst_depth > depth_reached)
5187 depth_reached = tinst_depth;
5194 /* We're done instantiating this template; return to the instantiation
5198 pop_tinst_level (void)
5200 tree old = current_tinst_level;
5202 /* Restore the filename and line number stashed away when we started
5203 this instantiation. */
5204 input_location = TINST_LOCATION (old);
5205 in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
5206 current_tinst_level = TREE_CHAIN (old);
5211 /* We're instantiating a deferred template; restore the template
5212 instantiation context in which the instantiation was requested, which
5213 is one step out from LEVEL. */
5216 reopen_tinst_level (tree level)
5221 for (t = level; t; t = TREE_CHAIN (t))
5224 current_tinst_level = level;
5228 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5229 vector of template arguments, as for tsubst.
5231 Returns an appropriate tsubst'd friend declaration. */
5234 tsubst_friend_function (tree decl, tree args)
5238 if (TREE_CODE (decl) == FUNCTION_DECL
5239 && DECL_TEMPLATE_INSTANTIATION (decl)
5240 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5241 /* This was a friend declared with an explicit template
5242 argument list, e.g.:
5246 to indicate that f was a template instantiation, not a new
5247 function declaration. Now, we have to figure out what
5248 instantiation of what template. */
5250 tree template_id, arglist, fns;
5253 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5255 /* Friend functions are looked up in the containing namespace scope.
5256 We must enter that scope, to avoid finding member functions of the
5257 current cless with same name. */
5258 push_nested_namespace (ns);
5259 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5260 tf_warning_or_error, NULL_TREE,
5261 /*integral_constant_expression_p=*/false);
5262 pop_nested_namespace (ns);
5263 arglist = tsubst (DECL_TI_ARGS (decl), args,
5264 tf_warning_or_error, NULL_TREE);
5265 template_id = lookup_template_function (fns, arglist);
5267 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
5268 tmpl = determine_specialization (template_id, new_friend,
5270 /*need_member_template=*/0,
5271 TREE_VEC_LENGTH (args),
5273 return instantiate_template (tmpl, new_args, tf_error);
5276 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
5278 /* The NEW_FRIEND will look like an instantiation, to the
5279 compiler, but is not an instantiation from the point of view of
5280 the language. For example, we might have had:
5282 template <class T> struct S {
5283 template <class U> friend void f(T, U);
5286 Then, in S<int>, template <class U> void f(int, U) is not an
5287 instantiation of anything. */
5288 if (new_friend == error_mark_node)
5289 return error_mark_node;
5291 DECL_USE_TEMPLATE (new_friend) = 0;
5292 if (TREE_CODE (decl) == TEMPLATE_DECL)
5294 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5295 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5296 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5299 /* The mangled name for the NEW_FRIEND is incorrect. The function
5300 is not a template instantiation and should not be mangled like
5301 one. Therefore, we forget the mangling here; we'll recompute it
5302 later if we need it. */
5303 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5305 SET_DECL_RTL (new_friend, NULL_RTX);
5306 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5309 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5312 tree new_friend_template_info;
5313 tree new_friend_result_template_info;
5315 int new_friend_is_defn;
5317 /* We must save some information from NEW_FRIEND before calling
5318 duplicate decls since that function will free NEW_FRIEND if
5320 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5321 new_friend_is_defn =
5322 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5323 (template_for_substitution (new_friend)))
5325 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5327 /* This declaration is a `primary' template. */
5328 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5330 new_friend_result_template_info
5331 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5334 new_friend_result_template_info = NULL_TREE;
5336 /* Inside pushdecl_namespace_level, we will push into the
5337 current namespace. However, the friend function should go
5338 into the namespace of the template. */
5339 ns = decl_namespace_context (new_friend);
5340 push_nested_namespace (ns);
5341 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
5342 pop_nested_namespace (ns);
5344 if (old_decl == error_mark_node)
5345 return error_mark_node;
5347 if (old_decl != new_friend)
5349 /* This new friend declaration matched an existing
5350 declaration. For example, given:
5352 template <class T> void f(T);
5353 template <class U> class C {
5354 template <class T> friend void f(T) {}
5357 the friend declaration actually provides the definition
5358 of `f', once C has been instantiated for some type. So,
5359 old_decl will be the out-of-class template declaration,
5360 while new_friend is the in-class definition.
5362 But, if `f' was called before this point, the
5363 instantiation of `f' will have DECL_TI_ARGS corresponding
5364 to `T' but not to `U', references to which might appear
5365 in the definition of `f'. Previously, the most general
5366 template for an instantiation of `f' was the out-of-class
5367 version; now it is the in-class version. Therefore, we
5368 run through all specialization of `f', adding to their
5369 DECL_TI_ARGS appropriately. In particular, they need a
5370 new set of outer arguments, corresponding to the
5371 arguments for this class instantiation.
5373 The same situation can arise with something like this:
5376 template <class T> class C {
5380 when `C<int>' is instantiated. Now, `f(int)' is defined
5383 if (!new_friend_is_defn)
5384 /* On the other hand, if the in-class declaration does
5385 *not* provide a definition, then we don't want to alter
5386 existing definitions. We can just leave everything
5391 /* Overwrite whatever template info was there before, if
5392 any, with the new template information pertaining to
5394 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5396 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5397 reregister_specialization (new_friend,
5398 most_general_template (old_decl),
5403 tree new_friend_args;
5405 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5406 = new_friend_result_template_info;
5408 new_friend_args = TI_ARGS (new_friend_template_info);
5409 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5413 tree spec = TREE_VALUE (t);
5416 = add_outermost_template_args (new_friend_args,
5417 DECL_TI_ARGS (spec));
5420 /* Now, since specializations are always supposed to
5421 hang off of the most general template, we must move
5423 t = most_general_template (old_decl);
5426 DECL_TEMPLATE_SPECIALIZATIONS (t)
5427 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5428 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5429 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5434 /* The information from NEW_FRIEND has been merged into OLD_DECL
5435 by duplicate_decls. */
5436 new_friend = old_decl;
5441 tree context = DECL_CONTEXT (new_friend);
5445 template <class T> class C {
5446 template <class U> friend void C1<U>::f (); // case 1
5447 friend void C2<T>::f (); // case 2
5449 we only need to make sure CONTEXT is a complete type for
5450 case 2. To distinguish between the two cases, we note that
5451 CONTEXT of case 1 remains dependent type after tsubst while
5452 this isn't true for case 2. */
5453 ++processing_template_decl;
5454 dependent_p = dependent_type_p (context);
5455 --processing_template_decl;
5458 && !complete_type_or_else (context, NULL_TREE))
5459 return error_mark_node;
5461 if (COMPLETE_TYPE_P (context))
5463 /* Check to see that the declaration is really present, and,
5464 possibly obtain an improved declaration. */
5465 tree fn = check_classfn (context,
5466 new_friend, NULL_TREE);
5476 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5477 template arguments, as for tsubst.
5479 Returns an appropriate tsubst'd friend type or error_mark_node on
5483 tsubst_friend_class (tree friend_tmpl, tree args)
5489 context = DECL_CONTEXT (friend_tmpl);
5493 if (TREE_CODE (context) == NAMESPACE_DECL)
5494 push_nested_namespace (context);
5496 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5499 /* Look for a class template declaration. We look for hidden names
5500 because two friend declarations of the same template are the
5501 same. For example, in:
5504 template <typename> friend class F;
5506 template <typename> struct B {
5507 template <typename> friend class F;
5510 both F templates are the same. */
5511 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
5512 /*block_p=*/true, 0,
5513 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
5515 /* But, if we don't find one, it might be because we're in a
5516 situation like this:
5524 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5525 for `S<int>', not the TEMPLATE_DECL. */
5526 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5528 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
5529 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5532 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5534 /* The friend template has already been declared. Just
5535 check to see that the declarations match, and install any new
5536 default parameters. We must tsubst the default parameters,
5537 of course. We only need the innermost template parameters
5538 because that is all that redeclare_class_template will look
5540 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5541 > TMPL_ARGS_DEPTH (args))
5544 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5545 args, tf_warning_or_error);
5546 redeclare_class_template (TREE_TYPE (tmpl), parms);
5549 friend_type = TREE_TYPE (tmpl);
5553 /* The friend template has not already been declared. In this
5554 case, the instantiation of the template class will cause the
5555 injection of this template into the global scope. */
5556 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
5557 if (tmpl == error_mark_node)
5558 return error_mark_node;
5560 /* The new TMPL is not an instantiation of anything, so we
5561 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5562 the new type because that is supposed to be the corresponding
5563 template decl, i.e., TMPL. */
5564 DECL_USE_TEMPLATE (tmpl) = 0;
5565 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5566 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5567 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5568 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5570 /* Inject this template into the global scope. */
5571 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
5576 if (TREE_CODE (context) == NAMESPACE_DECL)
5577 pop_nested_namespace (context);
5579 pop_nested_class ();
5585 /* Returns zero if TYPE cannot be completed later due to circularity.
5586 Otherwise returns one. */
5589 can_complete_type_without_circularity (tree type)
5591 if (type == NULL_TREE || type == error_mark_node)
5593 else if (COMPLETE_TYPE_P (type))
5595 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5596 return can_complete_type_without_circularity (TREE_TYPE (type));
5597 else if (CLASS_TYPE_P (type)
5598 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5605 instantiate_class_template (tree type)
5607 tree template, args, pattern, t, member;
5612 if (type == error_mark_node)
5613 return error_mark_node;
5615 if (TYPE_BEING_DEFINED (type)
5616 || COMPLETE_TYPE_P (type)
5617 || dependent_type_p (type))
5620 /* Figure out which template is being instantiated. */
5621 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5622 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5624 /* Determine what specialization of the original template to
5626 t = most_specialized_class (type, template);
5627 if (t == error_mark_node)
5629 TYPE_BEING_DEFINED (type) = 1;
5630 return error_mark_node;
5634 /* This TYPE is actually an instantiation of a partial
5635 specialization. We replace the innermost set of ARGS with
5636 the arguments appropriate for substitution. For example,
5639 template <class T> struct S {};
5640 template <class T> struct S<T*> {};
5642 and supposing that we are instantiating S<int*>, ARGS will
5643 presently be {int*} -- but we need {int}. */
5644 pattern = TREE_TYPE (t);
5645 args = TREE_PURPOSE (t);
5649 pattern = TREE_TYPE (template);
5650 args = CLASSTYPE_TI_ARGS (type);
5653 /* If the template we're instantiating is incomplete, then clearly
5654 there's nothing we can do. */
5655 if (!COMPLETE_TYPE_P (pattern))
5658 /* If we've recursively instantiated too many templates, stop. */
5659 if (! push_tinst_level (type))
5662 /* Now we're really doing the instantiation. Mark the type as in
5663 the process of being defined. */
5664 TYPE_BEING_DEFINED (type) = 1;
5666 /* We may be in the middle of deferred access check. Disable
5668 push_deferring_access_checks (dk_no_deferred);
5670 push_to_top_level ();
5672 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5674 /* Set the input location to the template definition. This is needed
5675 if tsubsting causes an error. */
5676 typedecl = TYPE_MAIN_DECL (type);
5677 input_location = DECL_SOURCE_LOCATION (typedecl);
5678 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
5680 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5681 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5682 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5683 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5684 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5685 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5686 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5687 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5688 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5689 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5690 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5691 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5692 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5693 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5694 if (ANON_AGGR_TYPE_P (pattern))
5695 SET_ANON_AGGR_TYPE_P (type);
5696 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
5698 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
5699 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
5702 pbinfo = TYPE_BINFO (pattern);
5704 /* We should never instantiate a nested class before its enclosing
5705 class; we need to look up the nested class by name before we can
5706 instantiate it, and that lookup should instantiate the enclosing
5708 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5709 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5710 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5712 base_list = NULL_TREE;
5713 if (BINFO_N_BASE_BINFOS (pbinfo))
5716 tree context = TYPE_CONTEXT (type);
5720 /* We must enter the scope containing the type, as that is where
5721 the accessibility of types named in dependent bases are
5723 pushed_scope = push_scope (context ? context : global_namespace);
5725 /* Substitute into each of the bases to determine the actual
5727 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5730 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5732 /* Substitute to figure out the base class. */
5733 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5734 if (base == error_mark_node)
5737 base_list = tree_cons (access, base, base_list);
5738 if (BINFO_VIRTUAL_P (pbase_binfo))
5739 TREE_TYPE (base_list) = integer_type_node;
5742 /* The list is now in reverse order; correct that. */
5743 base_list = nreverse (base_list);
5746 pop_scope (pushed_scope);
5748 /* Now call xref_basetypes to set up all the base-class
5750 xref_basetypes (type, base_list);
5753 /* Now that our base classes are set up, enter the scope of the
5754 class, so that name lookups into base classes, etc. will work
5755 correctly. This is precisely analogous to what we do in
5756 begin_class_definition when defining an ordinary non-template
5760 /* Now members are processed in the order of declaration. */
5761 for (member = CLASSTYPE_DECL_LIST (pattern);
5762 member; member = TREE_CHAIN (member))
5764 tree t = TREE_VALUE (member);
5766 if (TREE_PURPOSE (member))
5770 /* Build new CLASSTYPE_NESTED_UTDS. */
5773 bool class_template_p;
5775 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
5776 && TYPE_LANG_SPECIFIC (t)
5777 && CLASSTYPE_IS_TEMPLATE (t));
5778 /* If the member is a class template, then -- even after
5779 substitution -- there may be dependent types in the
5780 template argument list for the class. We increment
5781 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5782 that function will assume that no types are dependent
5783 when outside of a template. */
5784 if (class_template_p)
5785 ++processing_template_decl;
5786 newtag = tsubst (t, args, tf_error, NULL_TREE);
5787 if (class_template_p)
5788 --processing_template_decl;
5789 if (newtag == error_mark_node)
5792 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5794 tree name = TYPE_IDENTIFIER (t);
5796 if (class_template_p)
5797 /* Unfortunately, lookup_template_class sets
5798 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5799 instantiation (i.e., for the type of a member
5800 template class nested within a template class.)
5801 This behavior is required for
5802 maybe_process_partial_specialization to work
5803 correctly, but is not accurate in this case;
5804 the TAG is not an instantiation of anything.
5805 (The corresponding TEMPLATE_DECL is an
5806 instantiation, but the TYPE is not.) */
5807 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5809 /* Now, we call pushtag to put this NEWTAG into the scope of
5810 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5811 pushtag calling push_template_decl. We don't have to do
5812 this for enums because it will already have been done in
5815 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5816 pushtag (name, newtag, /*tag_scope=*/ts_current);
5819 else if (TREE_CODE (t) == FUNCTION_DECL
5820 || DECL_FUNCTION_TEMPLATE_P (t))
5822 /* Build new TYPE_METHODS. */
5825 if (TREE_CODE (t) == TEMPLATE_DECL)
5826 ++processing_template_decl;
5827 r = tsubst (t, args, tf_error, NULL_TREE);
5828 if (TREE_CODE (t) == TEMPLATE_DECL)
5829 --processing_template_decl;
5830 set_current_access_from_decl (r);
5831 finish_member_declaration (r);
5835 /* Build new TYPE_FIELDS. */
5837 if (TREE_CODE (t) != CONST_DECL)
5841 /* The the file and line for this declaration, to
5842 assist in error message reporting. Since we
5843 called push_tinst_level above, we don't need to
5845 input_location = DECL_SOURCE_LOCATION (t);
5847 if (TREE_CODE (t) == TEMPLATE_DECL)
5848 ++processing_template_decl;
5849 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
5850 if (TREE_CODE (t) == TEMPLATE_DECL)
5851 --processing_template_decl;
5852 if (TREE_CODE (r) == VAR_DECL)
5856 [t]he initialization (and any associated
5857 side-effects) of a static data member does
5858 not occur unless the static data member is
5859 itself used in a way that requires the
5860 definition of the static data member to
5863 Therefore, we do not substitute into the
5864 initialized for the static data member here. */
5865 finish_static_data_member_decl
5868 /*init_const_expr_p=*/false,
5869 /*asmspec_tree=*/NULL_TREE,
5871 if (DECL_INITIALIZED_IN_CLASS_P (r))
5872 check_static_variable_definition (r, TREE_TYPE (r));
5874 else if (TREE_CODE (r) == FIELD_DECL)
5876 /* Determine whether R has a valid type and can be
5877 completed later. If R is invalid, then it is
5878 replaced by error_mark_node so that it will not be
5879 added to TYPE_FIELDS. */
5880 tree rtype = TREE_TYPE (r);
5881 if (can_complete_type_without_circularity (rtype))
5882 complete_type (rtype);
5884 if (!COMPLETE_TYPE_P (rtype))
5886 cxx_incomplete_type_error (r, rtype);
5887 r = error_mark_node;
5891 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5892 such a thing will already have been added to the field
5893 list by tsubst_enum in finish_member_declaration in the
5894 CLASSTYPE_NESTED_UTDS case above. */
5895 if (!(TREE_CODE (r) == TYPE_DECL
5896 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5897 && DECL_ARTIFICIAL (r)))
5899 set_current_access_from_decl (r);
5900 finish_member_declaration (r);
5907 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5909 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5911 tree friend_type = t;
5912 bool adjust_processing_template_decl = false;
5914 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5916 /* template <class T> friend class C; */
5917 friend_type = tsubst_friend_class (friend_type, args);
5918 adjust_processing_template_decl = true;
5920 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5922 /* template <class T> friend class C::D; */
5923 friend_type = tsubst (friend_type, args,
5924 tf_warning_or_error, NULL_TREE);
5925 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5926 friend_type = TREE_TYPE (friend_type);
5927 adjust_processing_template_decl = true;
5929 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5931 /* This could be either
5935 when dependent_type_p is false or
5937 template <class U> friend class T::C;
5940 friend_type = tsubst (friend_type, args,
5941 tf_warning_or_error, NULL_TREE);
5942 /* Bump processing_template_decl for correct
5943 dependent_type_p calculation. */
5944 ++processing_template_decl;
5945 if (dependent_type_p (friend_type))
5946 adjust_processing_template_decl = true;
5947 --processing_template_decl;
5949 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
5950 && hidden_name_p (TYPE_NAME (friend_type)))
5954 where C hasn't been declared yet. Let's lookup name
5955 from namespace scope directly, bypassing any name that
5956 come from dependent base class. */
5957 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5959 /* The call to xref_tag_from_type does injection for friend
5961 push_nested_namespace (ns);
5963 xref_tag_from_type (friend_type, NULL_TREE,
5964 /*tag_scope=*/ts_current);
5965 pop_nested_namespace (ns);
5967 else if (uses_template_parms (friend_type))
5968 /* friend class C<T>; */
5969 friend_type = tsubst (friend_type, args,
5970 tf_warning_or_error, NULL_TREE);
5975 where C is already declared or
5977 friend class C<int>;
5979 We don't have to do anything in these cases. */
5981 if (adjust_processing_template_decl)
5982 /* Trick make_friend_class into realizing that the friend
5983 we're adding is a template, not an ordinary class. It's
5984 important that we use make_friend_class since it will
5985 perform some error-checking and output cross-reference
5987 ++processing_template_decl;
5989 if (friend_type != error_mark_node)
5990 make_friend_class (type, friend_type, /*complain=*/false);
5992 if (adjust_processing_template_decl)
5993 --processing_template_decl;
5997 /* Build new DECL_FRIENDLIST. */
6000 /* The the file and line for this declaration, to
6001 assist in error message reporting. Since we
6002 called push_tinst_level above, we don't need to
6004 input_location = DECL_SOURCE_LOCATION (t);
6006 if (TREE_CODE (t) == TEMPLATE_DECL)
6008 ++processing_template_decl;
6009 push_deferring_access_checks (dk_no_check);
6012 r = tsubst_friend_function (t, args);
6013 add_friend (type, r, /*complain=*/false);
6014 if (TREE_CODE (t) == TEMPLATE_DECL)
6016 pop_deferring_access_checks ();
6017 --processing_template_decl;
6023 /* Set the file and line number information to whatever is given for
6024 the class itself. This puts error messages involving generated
6025 implicit functions at a predictable point, and the same point
6026 that would be used for non-template classes. */
6027 input_location = DECL_SOURCE_LOCATION (typedecl);
6029 unreverse_member_declarations (type);
6030 finish_struct_1 (type);
6031 TYPE_BEING_DEFINED (type) = 0;
6033 /* Now that the class is complete, instantiate default arguments for
6034 any member functions. We don't do this earlier because the
6035 default arguments may reference members of the class. */
6036 if (!PRIMARY_TEMPLATE_P (template))
6037 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
6038 if (TREE_CODE (t) == FUNCTION_DECL
6039 /* Implicitly generated member functions will not have template
6040 information; they are not instantiations, but instead are
6041 created "fresh" for each instantiation. */
6042 && DECL_TEMPLATE_INFO (t))
6043 tsubst_default_arguments (t);
6046 pop_from_top_level ();
6047 pop_deferring_access_checks ();
6050 /* The vtable for a template class can be emitted in any translation
6051 unit in which the class is instantiated. When there is no key
6052 method, however, finish_struct_1 will already have added TYPE to
6053 the keyed_classes list. */
6054 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
6055 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
6061 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6067 else if (TYPE_P (t))
6068 r = tsubst (t, args, complain, in_decl);
6071 r = tsubst_expr (t, args, complain, in_decl,
6072 /*integral_constant_expression_p=*/true);
6073 r = fold_non_dependent_expr (r);
6078 /* Substitute ARGS into the vector or list of template arguments T. */
6081 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6083 int len = TREE_VEC_LENGTH (t);
6084 int need_new = 0, i;
6085 tree *elts = (tree *) alloca (len * sizeof (tree));
6087 for (i = 0; i < len; i++)
6089 tree orig_arg = TREE_VEC_ELT (t, i);
6092 if (TREE_CODE (orig_arg) == TREE_VEC)
6093 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
6095 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
6097 if (new_arg == error_mark_node)
6098 return error_mark_node;
6101 if (new_arg != orig_arg)
6108 t = make_tree_vec (len);
6109 for (i = 0; i < len; i++)
6110 TREE_VEC_ELT (t, i) = elts[i];
6115 /* Return the result of substituting ARGS into the template parameters
6116 given by PARMS. If there are m levels of ARGS and m + n levels of
6117 PARMS, then the result will contain n levels of PARMS. For
6118 example, if PARMS is `template <class T> template <class U>
6119 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
6120 result will be `template <int*, double, class V>'. */
6123 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
6128 /* When substituting into a template, we must set
6129 PROCESSING_TEMPLATE_DECL as the template parameters may be
6130 dependent if they are based on one-another, and the dependency
6131 predicates are short-circuit outside of templates. */
6132 ++processing_template_decl;
6134 for (new_parms = &r;
6135 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
6136 new_parms = &(TREE_CHAIN (*new_parms)),
6137 parms = TREE_CHAIN (parms))
6140 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
6143 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
6149 if (parms == error_mark_node)
6152 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
6154 if (tuple == error_mark_node)
6157 default_value = TREE_PURPOSE (tuple);
6158 parm_decl = TREE_VALUE (tuple);
6160 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
6161 if (TREE_CODE (parm_decl) == PARM_DECL
6162 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
6163 parm_decl = error_mark_node;
6164 default_value = tsubst_template_arg (default_value, args,
6165 complain, NULL_TREE);
6167 tuple = build_tree_list (default_value, parm_decl);
6168 TREE_VEC_ELT (new_vec, i) = tuple;
6172 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6173 - TMPL_ARGS_DEPTH (args)),
6174 new_vec, NULL_TREE);
6177 --processing_template_decl;
6182 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6183 type T. If T is not an aggregate or enumeration type, it is
6184 handled as if by tsubst. IN_DECL is as for tsubst. If
6185 ENTERING_SCOPE is nonzero, T is the context for a template which
6186 we are presently tsubst'ing. Return the substituted value. */
6189 tsubst_aggr_type (tree t,
6191 tsubst_flags_t complain,
6198 switch (TREE_CODE (t))
6201 if (TYPE_PTRMEMFUNC_P (t))
6202 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6204 /* Else fall through. */
6207 if (TYPE_TEMPLATE_INFO (t))
6212 bool saved_skip_evaluation;
6214 /* In "sizeof(X<I>)" we need to evaluate "I". */
6215 saved_skip_evaluation = skip_evaluation;
6216 skip_evaluation = false;
6218 /* First, determine the context for the type we are looking
6220 context = TYPE_CONTEXT (t);
6222 context = tsubst_aggr_type (context, args, complain,
6223 in_decl, /*entering_scope=*/1);
6225 /* Then, figure out what arguments are appropriate for the
6226 type we are trying to find. For example, given:
6228 template <class T> struct S;
6229 template <class T, class U> void f(T, U) { S<U> su; }
6231 and supposing that we are instantiating f<int, double>,
6232 then our ARGS will be {int, double}, but, when looking up
6233 S we only want {double}. */
6234 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6236 if (argvec == error_mark_node)
6237 r = error_mark_node;
6240 r = lookup_template_class (t, argvec, in_decl, context,
6241 entering_scope, complain);
6242 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6245 skip_evaluation = saved_skip_evaluation;
6250 /* This is not a template type, so there's nothing to do. */
6254 return tsubst (t, args, complain, in_decl);
6258 /* Substitute into the default argument ARG (a default argument for
6259 FN), which has the indicated TYPE. */
6262 tsubst_default_argument (tree fn, tree type, tree arg)
6264 tree saved_class_ptr = NULL_TREE;
6265 tree saved_class_ref = NULL_TREE;
6267 /* This default argument came from a template. Instantiate the
6268 default argument here, not in tsubst. In the case of
6277 we must be careful to do name lookup in the scope of S<T>,
6278 rather than in the current class. */
6279 push_access_scope (fn);
6280 /* The "this" pointer is not valid in a default argument. */
6283 saved_class_ptr = current_class_ptr;
6284 cp_function_chain->x_current_class_ptr = NULL_TREE;
6285 saved_class_ref = current_class_ref;
6286 cp_function_chain->x_current_class_ref = NULL_TREE;
6289 push_deferring_access_checks(dk_no_deferred);
6290 /* The default argument expression may cause implicitly defined
6291 member functions to be synthesized, which will result in garbage
6292 collection. We must treat this situation as if we were within
6293 the body of function so as to avoid collecting live data on the
6296 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6297 tf_warning_or_error, NULL_TREE,
6298 /*integral_constant_expression_p=*/false);
6300 pop_deferring_access_checks();
6302 /* Restore the "this" pointer. */
6305 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6306 cp_function_chain->x_current_class_ref = saved_class_ref;
6309 pop_access_scope (fn);
6311 /* Make sure the default argument is reasonable. */
6312 arg = check_default_argument (type, arg);
6317 /* Substitute into all the default arguments for FN. */
6320 tsubst_default_arguments (tree fn)
6325 tmpl_args = DECL_TI_ARGS (fn);
6327 /* If this function is not yet instantiated, we certainly don't need
6328 its default arguments. */
6329 if (uses_template_parms (tmpl_args))
6332 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6334 arg = TREE_CHAIN (arg))
6335 if (TREE_PURPOSE (arg))
6336 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6338 TREE_PURPOSE (arg));
6341 /* Substitute the ARGS into the T, which is a _DECL. Return the
6342 result of the substitution. Issue error and warning messages under
6343 control of COMPLAIN. */
6346 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6348 location_t saved_loc;
6352 /* Set the filename and linenumber to improve error-reporting. */
6353 saved_loc = input_location;
6354 input_location = DECL_SOURCE_LOCATION (t);
6356 switch (TREE_CODE (t))
6360 /* We can get here when processing a member function template,
6361 member class template, and template template parameter of
6362 a template class. */
6363 tree decl = DECL_TEMPLATE_RESULT (t);
6368 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6370 /* Template template parameter is treated here. */
6371 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6372 if (new_type == error_mark_node)
6373 return error_mark_node;
6376 TREE_CHAIN (r) = NULL_TREE;
6377 TREE_TYPE (r) = new_type;
6378 DECL_TEMPLATE_RESULT (r)
6379 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6380 DECL_TEMPLATE_PARMS (r)
6381 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6383 TYPE_NAME (new_type) = r;
6387 /* We might already have an instance of this template.
6388 The ARGS are for the surrounding class type, so the
6389 full args contain the tsubst'd args for the context,
6390 plus the innermost args from the template decl. */
6391 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6392 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6393 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6394 /* Because this is a template, the arguments will still be
6395 dependent, even after substitution. If
6396 PROCESSING_TEMPLATE_DECL is not set, the dependency
6397 predicates will short-circuit. */
6398 ++processing_template_decl;
6399 full_args = tsubst_template_args (tmpl_args, args,
6401 --processing_template_decl;
6402 if (full_args == error_mark_node)
6403 return error_mark_node;
6405 /* tsubst_template_args doesn't copy the vector if
6406 nothing changed. But, *something* should have
6408 gcc_assert (full_args != tmpl_args);
6410 spec = retrieve_specialization (t, full_args,
6411 /*class_specializations_p=*/true);
6412 if (spec != NULL_TREE)
6418 /* Make a new template decl. It will be similar to the
6419 original, but will record the current template arguments.
6420 We also create a new function declaration, which is just
6421 like the old one, but points to this new template, rather
6422 than the old one. */
6424 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6425 TREE_CHAIN (r) = NULL_TREE;
6427 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6429 if (TREE_CODE (decl) == TYPE_DECL)
6432 ++processing_template_decl;
6433 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6434 --processing_template_decl;
6435 if (new_type == error_mark_node)
6436 return error_mark_node;
6438 TREE_TYPE (r) = new_type;
6439 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6440 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6441 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6442 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
6447 ++processing_template_decl;
6448 new_decl = tsubst (decl, args, complain, in_decl);
6449 --processing_template_decl;
6450 if (new_decl == error_mark_node)
6451 return error_mark_node;
6453 DECL_TEMPLATE_RESULT (r) = new_decl;
6454 DECL_TI_TEMPLATE (new_decl) = r;
6455 TREE_TYPE (r) = TREE_TYPE (new_decl);
6456 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6457 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
6460 SET_DECL_IMPLICIT_INSTANTIATION (r);
6461 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6462 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6464 /* The template parameters for this new template are all the
6465 template parameters for the old template, except the
6466 outermost level of parameters. */
6467 DECL_TEMPLATE_PARMS (r)
6468 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6471 if (PRIMARY_TEMPLATE_P (t))
6472 DECL_PRIMARY_TEMPLATE (r) = r;
6474 if (TREE_CODE (decl) != TYPE_DECL)
6475 /* Record this non-type partial instantiation. */
6476 register_specialization (r, t,
6477 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
6485 tree argvec = NULL_TREE;
6493 /* Nobody should be tsubst'ing into non-template functions. */
6494 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6496 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6501 /* If T is not dependent, just return it. We have to
6502 increment PROCESSING_TEMPLATE_DECL because
6503 value_dependent_expression_p assumes that nothing is
6504 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6505 ++processing_template_decl;
6506 dependent_p = value_dependent_expression_p (t);
6507 --processing_template_decl;
6511 /* Calculate the most general template of which R is a
6512 specialization, and the complete set of arguments used to
6514 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6515 argvec = tsubst_template_args (DECL_TI_ARGS
6516 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6517 args, complain, in_decl);
6519 /* Check to see if we already have this specialization. */
6520 spec = retrieve_specialization (gen_tmpl, argvec,
6521 /*class_specializations_p=*/false);
6529 /* We can see more levels of arguments than parameters if
6530 there was a specialization of a member template, like
6533 template <class T> struct S { template <class U> void f(); }
6534 template <> template <class U> void S<int>::f(U);
6536 Here, we'll be substituting into the specialization,
6537 because that's where we can find the code we actually
6538 want to generate, but we'll have enough arguments for
6539 the most general template.
6541 We also deal with the peculiar case:
6543 template <class T> struct S {
6544 template <class U> friend void f();
6546 template <class U> void f() {}
6548 template void f<double>();
6550 Here, the ARGS for the instantiation of will be {int,
6551 double}. But, we only need as many ARGS as there are
6552 levels of template parameters in CODE_PATTERN. We are
6553 careful not to get fooled into reducing the ARGS in
6556 template <class T> struct S { template <class U> void f(U); }
6557 template <class T> template <> void S<T>::f(int) {}
6559 which we can spot because the pattern will be a
6560 specialization in this case. */
6561 args_depth = TMPL_ARGS_DEPTH (args);
6563 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6564 if (args_depth > parms_depth
6565 && !DECL_TEMPLATE_SPECIALIZATION (t))
6566 args = get_innermost_template_args (args, parms_depth);
6570 /* This special case arises when we have something like this:
6572 template <class T> struct S {
6573 friend void f<int>(int, double);
6576 Here, the DECL_TI_TEMPLATE for the friend declaration
6577 will be an IDENTIFIER_NODE. We are being called from
6578 tsubst_friend_function, and we want only to create a
6579 new decl (R) with appropriate types so that we can call
6580 determine_specialization. */
6581 gen_tmpl = NULL_TREE;
6584 if (DECL_CLASS_SCOPE_P (t))
6586 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6590 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6591 complain, t, /*entering_scope=*/1);
6596 ctx = DECL_CONTEXT (t);
6598 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6599 if (type == error_mark_node)
6600 return error_mark_node;
6602 /* We do NOT check for matching decls pushed separately at this
6603 point, as they may not represent instantiations of this
6604 template, and in any case are considered separate under the
6607 DECL_USE_TEMPLATE (r) = 0;
6608 TREE_TYPE (r) = type;
6609 /* Clear out the mangled name and RTL for the instantiation. */
6610 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6611 SET_DECL_RTL (r, NULL_RTX);
6612 DECL_INITIAL (r) = NULL_TREE;
6613 DECL_CONTEXT (r) = ctx;
6615 if (member && DECL_CONV_FN_P (r))
6616 /* Type-conversion operator. Reconstruct the name, in
6617 case it's the name of one of the template's parameters. */
6618 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6620 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6622 DECL_RESULT (r) = NULL_TREE;
6624 TREE_STATIC (r) = 0;
6625 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6626 DECL_EXTERNAL (r) = 1;
6627 /* If this is an instantiation of a function with internal
6628 linkage, we already know what object file linkage will be
6629 assigned to the instantiation. */
6630 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6631 DECL_DEFER_OUTPUT (r) = 0;
6632 TREE_CHAIN (r) = NULL_TREE;
6633 DECL_PENDING_INLINE_INFO (r) = 0;
6634 DECL_PENDING_INLINE_P (r) = 0;
6635 DECL_SAVED_TREE (r) = NULL_TREE;
6637 if (DECL_CLONED_FUNCTION (r))
6639 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6641 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6642 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6645 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6646 this in the special friend case mentioned above where
6647 GEN_TMPL is NULL. */
6650 DECL_TEMPLATE_INFO (r)
6651 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6652 SET_DECL_IMPLICIT_INSTANTIATION (r);
6653 register_specialization (r, gen_tmpl, argvec, false);
6655 /* We're not supposed to instantiate default arguments
6656 until they are called, for a template. But, for a
6659 template <class T> void f ()
6660 { extern void g(int i = T()); }
6662 we should do the substitution when the template is
6663 instantiated. We handle the member function case in
6664 instantiate_class_template since the default arguments
6665 might refer to other members of the class. */
6667 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6668 && !uses_template_parms (argvec))
6669 tsubst_default_arguments (r);
6672 DECL_TEMPLATE_INFO (r) = NULL_TREE;
6674 /* Copy the list of befriending classes. */
6675 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6677 friends = &TREE_CHAIN (*friends))
6679 *friends = copy_node (*friends);
6680 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6685 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6687 maybe_retrofit_in_chrg (r);
6688 if (DECL_CONSTRUCTOR_P (r))
6689 grok_ctor_properties (ctx, r);
6690 /* If this is an instantiation of a member template, clone it.
6691 If it isn't, that'll be handled by
6692 clone_constructors_and_destructors. */
6693 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6694 clone_function_decl (r, /*update_method_vec_p=*/0);
6696 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r))
6697 && !grok_op_properties (r, (complain & tf_error) != 0))
6698 return error_mark_node;
6700 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6701 SET_DECL_FRIEND_CONTEXT (r,
6702 tsubst (DECL_FRIEND_CONTEXT (t),
6703 args, complain, in_decl));
6705 /* Possibly limit visibility based on template args. */
6706 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
6707 if (DECL_VISIBILITY_SPECIFIED (t))
6709 DECL_VISIBILITY_SPECIFIED (r) = 0;
6711 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
6713 determine_visibility (r);
6722 if (DECL_TEMPLATE_PARM_P (t))
6723 SET_DECL_TEMPLATE_PARM_P (r);
6725 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6726 type = type_decays_to (type);
6727 TREE_TYPE (r) = type;
6728 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6730 if (DECL_INITIAL (r))
6732 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6733 DECL_INITIAL (r) = TREE_TYPE (r);
6735 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6739 DECL_CONTEXT (r) = NULL_TREE;
6741 if (!DECL_TEMPLATE_PARM_P (r))
6742 DECL_ARG_TYPE (r) = type_passed_as (type);
6744 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6745 complain, TREE_CHAIN (t));
6754 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6755 if (type == error_mark_node)
6756 return error_mark_node;
6757 TREE_TYPE (r) = type;
6758 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6760 /* DECL_INITIAL gives the number of bits in a bit-field. */
6762 = tsubst_expr (DECL_INITIAL (t), args,
6764 /*integral_constant_expression_p=*/true);
6765 /* We don't have to set DECL_CONTEXT here; it is set by
6766 finish_member_declaration. */
6767 TREE_CHAIN (r) = NULL_TREE;
6768 if (VOID_TYPE_P (type))
6769 error ("instantiation of %q+D as type %qT", r, type);
6774 /* We reach here only for member using decls. */
6775 if (DECL_DEPENDENT_P (t))
6777 r = do_class_using_decl
6778 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
6779 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
6781 r = error_mark_node;
6786 TREE_CHAIN (r) = NULL_TREE;
6793 tree argvec = NULL_TREE;
6794 tree gen_tmpl = NULL_TREE;
6796 tree tmpl = NULL_TREE;
6798 tree type = NULL_TREE;
6801 if (TREE_CODE (t) == TYPE_DECL)
6803 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6804 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6805 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6807 /* If this is the canonical decl, we don't have to
6808 mess with instantiations, and often we can't (for
6809 typename, template type parms and such). Note that
6810 TYPE_NAME is not correct for the above test if
6811 we've copied the type for a typedef. */
6812 r = TYPE_NAME (type);
6817 /* Check to see if we already have the specialization we
6820 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
6822 /* T is a static data member or namespace-scope entity.
6823 We have to substitute into namespace-scope variables
6824 (even though such entities are never templates) because
6827 template <class T> void f() { extern T t; }
6829 where the entity referenced is not known until
6830 instantiation time. */
6832 ctx = DECL_CONTEXT (t);
6833 if (DECL_CLASS_SCOPE_P (t))
6835 ctx = tsubst_aggr_type (ctx, args,
6837 in_decl, /*entering_scope=*/1);
6838 /* If CTX is unchanged, then T is in fact the
6839 specialization we want. That situation occurs when
6840 referencing a static data member within in its own
6841 class. We can use pointer equality, rather than
6842 same_type_p, because DECL_CONTEXT is always
6844 if (ctx == DECL_CONTEXT (t))
6850 tmpl = DECL_TI_TEMPLATE (t);
6851 gen_tmpl = most_general_template (tmpl);
6852 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6853 spec = (retrieve_specialization
6855 /*class_specializations_p=*/false));
6860 /* A local variable. */
6862 /* Subsequent calls to pushdecl will fill this in. */
6864 spec = retrieve_local_specialization (t);
6866 /* If we already have the specialization we need, there is
6867 nothing more to do. */
6874 /* Create a new node for the specialization we need. */
6876 if (TREE_CODE (r) == VAR_DECL)
6878 /* Even if the original location is out of scope, the
6879 newly substituted one is not. */
6880 DECL_DEAD_FOR_LOCAL (r) = 0;
6881 DECL_INITIALIZED_P (r) = 0;
6882 DECL_TEMPLATE_INSTANTIATED (r) = 0;
6883 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6884 if (type == error_mark_node)
6885 return error_mark_node;
6886 type = complete_type (type);
6887 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6888 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6889 type = check_var_type (DECL_NAME (r), type);
6891 if (DECL_HAS_VALUE_EXPR_P (t))
6893 tree ve = DECL_VALUE_EXPR (t);
6894 ve = tsubst_expr (ve, args, complain, in_decl,
6895 /*constant_expression_p=*/false);
6896 SET_DECL_VALUE_EXPR (r, ve);
6899 else if (DECL_SELF_REFERENCE_P (t))
6900 SET_DECL_SELF_REFERENCE_P (r);
6901 TREE_TYPE (r) = type;
6902 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6903 DECL_CONTEXT (r) = ctx;
6904 /* Clear out the mangled name and RTL for the instantiation. */
6905 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6906 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6907 SET_DECL_RTL (r, NULL_RTX);
6908 /* The initializer must not be expanded until it is required;
6910 DECL_INITIAL (r) = NULL_TREE;
6911 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6912 SET_DECL_RTL (r, NULL_RTX);
6913 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6914 if (TREE_CODE (r) == VAR_DECL)
6916 /* Possibly limit visibility based on template args. */
6917 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
6918 if (DECL_VISIBILITY_SPECIFIED (t))
6920 DECL_VISIBILITY_SPECIFIED (r) = 0;
6922 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
6924 determine_visibility (r);
6929 /* A static data member declaration is always marked
6930 external when it is declared in-class, even if an
6931 initializer is present. We mimic the non-template
6933 DECL_EXTERNAL (r) = 1;
6935 register_specialization (r, gen_tmpl, argvec, false);
6936 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6937 SET_DECL_IMPLICIT_INSTANTIATION (r);
6940 register_local_specialization (r, t);
6942 TREE_CHAIN (r) = NULL_TREE;
6951 /* Restore the file and line information. */
6952 input_location = saved_loc;
6957 /* Substitute into the ARG_TYPES of a function type. */
6960 tsubst_arg_types (tree arg_types,
6962 tsubst_flags_t complain,
6965 tree remaining_arg_types;
6968 tree result = NULL_TREE;
6970 if (!arg_types || arg_types == void_list_node)
6973 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6974 args, complain, in_decl);
6975 if (remaining_arg_types == error_mark_node)
6976 return error_mark_node;
6978 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6979 if (type == error_mark_node)
6980 return error_mark_node;
6981 if (VOID_TYPE_P (type))
6983 if (complain & tf_error)
6985 error ("invalid parameter type %qT", type);
6987 error ("in declaration %q+D", in_decl);
6989 return error_mark_node;
6992 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6993 top-level qualifiers as required. */
6994 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6996 /* We do not substitute into default arguments here. The standard
6997 mandates that they be instantiated only when needed, which is
6998 done in build_over_call. */
6999 default_arg = TREE_PURPOSE (arg_types);
7001 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
7003 /* We've instantiated a template before its default arguments
7004 have been parsed. This can happen for a nested template
7005 class, and is not an error unless we require the default
7006 argument in a call of this function. */
7007 result = tree_cons (default_arg, type, remaining_arg_types);
7008 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
7011 result = hash_tree_cons (default_arg, type, remaining_arg_types);
7016 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
7017 *not* handle the exception-specification for FNTYPE, because the
7018 initial substitution of explicitly provided template parameters
7019 during argument deduction forbids substitution into the
7020 exception-specification:
7024 All references in the function type of the function template to the
7025 corresponding template parameters are replaced by the specified tem-
7026 plate argument values. If a substitution in a template parameter or
7027 in the function type of the function template results in an invalid
7028 type, type deduction fails. [Note: The equivalent substitution in
7029 exception specifications is done only when the function is instanti-
7030 ated, at which point a program is ill-formed if the substitution
7031 results in an invalid type.] */
7034 tsubst_function_type (tree t,
7036 tsubst_flags_t complain,
7043 /* The TYPE_CONTEXT is not used for function/method types. */
7044 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
7046 /* Substitute the return type. */
7047 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7048 if (return_type == error_mark_node)
7049 return error_mark_node;
7050 /* The standard does not presently indicate that creation of a
7051 function type with an invalid return type is a deduction failure.
7052 However, that is clearly analogous to creating an array of "void"
7053 or a reference to a reference. This is core issue #486. */
7054 if (TREE_CODE (return_type) == ARRAY_TYPE
7055 || TREE_CODE (return_type) == FUNCTION_TYPE)
7057 if (complain & tf_error)
7059 if (TREE_CODE (return_type) == ARRAY_TYPE)
7060 error ("function returning an array");
7062 error ("function returning a function");
7064 return error_mark_node;
7067 /* Substitute the argument types. */
7068 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
7070 if (arg_types == error_mark_node)
7071 return error_mark_node;
7073 /* Construct a new type node and return it. */
7074 if (TREE_CODE (t) == FUNCTION_TYPE)
7075 fntype = build_function_type (return_type, arg_types);
7078 tree r = TREE_TYPE (TREE_VALUE (arg_types));
7079 if (! IS_AGGR_TYPE (r))
7083 Type deduction may fail for any of the following
7086 -- Attempting to create "pointer to member of T" when T
7087 is not a class type. */
7088 if (complain & tf_error)
7089 error ("creating pointer to member function of non-class type %qT",
7091 return error_mark_node;
7094 fntype = build_method_type_directly (r, return_type,
7095 TREE_CHAIN (arg_types));
7097 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
7098 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
7103 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
7104 ARGS into that specification, and return the substituted
7105 specification. If there is no specification, return NULL_TREE. */
7108 tsubst_exception_specification (tree fntype,
7110 tsubst_flags_t complain,
7116 specs = TYPE_RAISES_EXCEPTIONS (fntype);
7117 new_specs = NULL_TREE;
7120 if (! TREE_VALUE (specs))
7126 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
7127 if (spec == error_mark_node)
7129 new_specs = add_exception_specifier (new_specs, spec, complain);
7130 specs = TREE_CHAIN (specs);
7136 /* Take the tree structure T and replace template parameters used
7137 therein with the argument vector ARGS. IN_DECL is an associated
7138 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
7139 Issue error and warning messages under control of COMPLAIN. Note
7140 that we must be relatively non-tolerant of extensions here, in
7141 order to preserve conformance; if we allow substitutions that
7142 should not be allowed, we may allow argument deductions that should
7143 not succeed, and therefore report ambiguous overload situations
7144 where there are none. In theory, we could allow the substitution,
7145 but indicate that it should have failed, and allow our caller to
7146 make sure that the right thing happens, but we don't try to do this
7149 This function is used for dealing with types, decls and the like;
7150 for expressions, use tsubst_expr or tsubst_copy. */
7153 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7157 if (t == NULL_TREE || t == error_mark_node
7158 || t == integer_type_node
7159 || t == void_type_node
7160 || t == char_type_node
7161 || t == unknown_type_node
7162 || TREE_CODE (t) == NAMESPACE_DECL)
7166 return tsubst_decl (t, args, complain);
7168 if (TREE_CODE (t) == IDENTIFIER_NODE)
7169 type = IDENTIFIER_TYPE_VALUE (t);
7171 type = TREE_TYPE (t);
7173 gcc_assert (type != unknown_type_node);
7176 && TREE_CODE (t) != TYPENAME_TYPE
7177 && TREE_CODE (t) != IDENTIFIER_NODE
7178 && TREE_CODE (t) != FUNCTION_TYPE
7179 && TREE_CODE (t) != METHOD_TYPE)
7180 type = tsubst (type, args, complain, in_decl);
7181 if (type == error_mark_node)
7182 return error_mark_node;
7184 switch (TREE_CODE (t))
7189 return tsubst_aggr_type (t, args, complain, in_decl,
7190 /*entering_scope=*/0);
7193 case IDENTIFIER_NODE:
7205 if (t == integer_type_node)
7208 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
7209 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
7213 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
7215 /* The array dimension behaves like a non-type template arg,
7216 in that we want to fold it as much as possible. */
7217 max = tsubst_template_arg (omax, args, complain, in_decl);
7218 max = fold_decl_constant_value (max);
7220 if (TREE_CODE (max) != INTEGER_CST
7221 && TREE_CODE (max) != TEMPLATE_PARM_INDEX
7222 && !at_function_scope_p ())
7224 if (complain & tf_error)
7225 error ("array bound is not an integer constant");
7226 return error_mark_node;
7231 Type deduction may fail for any of the following
7234 Attempting to create an array with a size that is
7235 zero or negative. */
7236 if (integer_zerop (max) && !(complain & tf_error))
7237 /* We must fail if performing argument deduction (as
7238 indicated by the state of complain), so that
7239 another substitution can be found. */
7240 return error_mark_node;
7241 else if (TREE_CODE (max) == INTEGER_CST
7242 && INT_CST_LT (max, integer_zero_node))
7244 if (complain & tf_error)
7245 error ("creating array with negative size (%qE)", max);
7247 return error_mark_node;
7250 return compute_array_index_type (NULL_TREE, max);
7253 case TEMPLATE_TYPE_PARM:
7254 case TEMPLATE_TEMPLATE_PARM:
7255 case BOUND_TEMPLATE_TEMPLATE_PARM:
7256 case TEMPLATE_PARM_INDEX:
7261 tree arg = NULL_TREE;
7265 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7266 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7267 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7268 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7270 idx = TEMPLATE_TYPE_IDX (t);
7271 level = TEMPLATE_TYPE_LEVEL (t);
7275 idx = TEMPLATE_PARM_IDX (t);
7276 level = TEMPLATE_PARM_LEVEL (t);
7279 levels = TMPL_ARGS_DEPTH (args);
7280 if (level <= levels)
7281 arg = TMPL_ARG (args, level, idx);
7283 if (arg == error_mark_node)
7284 return error_mark_node;
7285 else if (arg != NULL_TREE)
7287 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7290 gcc_assert (TYPE_P (arg));
7292 /* cv-quals from the template are discarded when
7293 substituting in a function or reference type. */
7294 if (TREE_CODE (arg) == FUNCTION_TYPE
7295 || TREE_CODE (arg) == METHOD_TYPE
7296 || TREE_CODE (arg) == REFERENCE_TYPE)
7297 quals = cp_type_quals (arg);
7299 quals = cp_type_quals (arg) | cp_type_quals (t);
7301 return cp_build_qualified_type_real
7302 (arg, quals, complain | tf_ignore_bad_quals);
7304 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7306 /* We are processing a type constructed from a
7307 template template parameter. */
7308 tree argvec = tsubst (TYPE_TI_ARGS (t),
7309 args, complain, in_decl);
7310 if (argvec == error_mark_node)
7311 return error_mark_node;
7313 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7314 are resolving nested-types in the signature of a
7315 member function templates. Otherwise ARG is a
7316 TEMPLATE_DECL and is the real template to be
7318 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7319 arg = TYPE_NAME (arg);
7321 r = lookup_template_class (arg,
7324 /*entering_scope=*/0,
7326 return cp_build_qualified_type_real
7327 (r, TYPE_QUALS (t), complain);
7330 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7335 /* This can happen during the attempted tsubst'ing in
7336 unify. This means that we don't yet have any information
7337 about the template parameter in question. */
7340 /* If we get here, we must have been looking at a parm for a
7341 more deeply nested template. Make a new version of this
7342 template parameter, but with a lower level. */
7343 switch (TREE_CODE (t))
7345 case TEMPLATE_TYPE_PARM:
7346 case TEMPLATE_TEMPLATE_PARM:
7347 case BOUND_TEMPLATE_TEMPLATE_PARM:
7348 if (cp_type_quals (t))
7350 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7351 r = cp_build_qualified_type_real
7352 (r, cp_type_quals (t),
7353 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7354 ? tf_ignore_bad_quals : 0));
7359 TEMPLATE_TYPE_PARM_INDEX (r)
7360 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7362 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7363 TYPE_MAIN_VARIANT (r) = r;
7364 TYPE_POINTER_TO (r) = NULL_TREE;
7365 TYPE_REFERENCE_TO (r) = NULL_TREE;
7367 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7369 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7371 if (argvec == error_mark_node)
7372 return error_mark_node;
7374 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7375 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7380 case TEMPLATE_PARM_INDEX:
7381 r = reduce_template_parm_level (t, type, levels);
7393 tree purpose, value, chain;
7395 if (t == void_list_node)
7398 purpose = TREE_PURPOSE (t);
7401 purpose = tsubst (purpose, args, complain, in_decl);
7402 if (purpose == error_mark_node)
7403 return error_mark_node;
7405 value = TREE_VALUE (t);
7408 value = tsubst (value, args, complain, in_decl);
7409 if (value == error_mark_node)
7410 return error_mark_node;
7412 chain = TREE_CHAIN (t);
7413 if (chain && chain != void_type_node)
7415 chain = tsubst (chain, args, complain, in_decl);
7416 if (chain == error_mark_node)
7417 return error_mark_node;
7419 if (purpose == TREE_PURPOSE (t)
7420 && value == TREE_VALUE (t)
7421 && chain == TREE_CHAIN (t))
7423 return hash_tree_cons (purpose, value, chain);
7427 /* We should never be tsubsting a binfo. */
7431 /* A vector of template arguments. */
7433 return tsubst_template_args (t, args, complain, in_decl);
7436 case REFERENCE_TYPE:
7438 enum tree_code code;
7440 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7443 code = TREE_CODE (t);
7448 Type deduction may fail for any of the following
7451 -- Attempting to create a pointer to reference type.
7452 -- Attempting to create a reference to a reference type or
7453 a reference to void. */
7454 if (TREE_CODE (type) == REFERENCE_TYPE
7455 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7457 static location_t last_loc;
7459 /* We keep track of the last time we issued this error
7460 message to avoid spewing a ton of messages during a
7461 single bad template instantiation. */
7462 if (complain & tf_error
7463 #ifdef USE_MAPPED_LOCATION
7464 && last_loc != input_location
7466 && (last_loc.line != input_line
7467 || last_loc.file != input_filename)
7471 if (TREE_CODE (type) == VOID_TYPE)
7472 error ("forming reference to void");
7474 error ("forming %s to reference type %qT",
7475 (code == POINTER_TYPE) ? "pointer" : "reference",
7477 last_loc = input_location;
7480 return error_mark_node;
7482 else if (code == POINTER_TYPE)
7484 r = build_pointer_type (type);
7485 if (TREE_CODE (type) == METHOD_TYPE)
7486 r = build_ptrmemfunc_type (r);
7489 r = build_reference_type (type);
7490 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7492 if (r != error_mark_node)
7493 /* Will this ever be needed for TYPE_..._TO values? */
7500 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7501 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7505 Type deduction may fail for any of the following
7508 -- Attempting to create "pointer to member of T" when T
7509 is not a class type. */
7510 if (complain & tf_error)
7511 error ("creating pointer to member of non-class type %qT", r);
7512 return error_mark_node;
7514 if (TREE_CODE (type) == REFERENCE_TYPE)
7516 if (complain & tf_error)
7517 error ("creating pointer to member reference type %qT", type);
7518 return error_mark_node;
7520 if (TREE_CODE (type) == VOID_TYPE)
7522 if (complain & tf_error)
7523 error ("creating pointer to member of type void");
7524 return error_mark_node;
7526 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7527 if (TREE_CODE (type) == FUNCTION_TYPE)
7529 /* The type of the implicit object parameter gets its
7530 cv-qualifiers from the FUNCTION_TYPE. */
7532 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7533 cp_type_quals (type));
7535 method_type = build_method_type_directly (this_type,
7537 TYPE_ARG_TYPES (type));
7538 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7539 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7543 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7552 fntype = tsubst_function_type (t, args, complain, in_decl);
7553 if (fntype == error_mark_node)
7554 return error_mark_node;
7556 /* Substitute the exception specification. */
7557 specs = tsubst_exception_specification (t, args, complain,
7559 if (specs == error_mark_node)
7560 return error_mark_node;
7562 fntype = build_exception_variant (fntype, specs);
7567 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7568 if (domain == error_mark_node)
7569 return error_mark_node;
7571 /* As an optimization, we avoid regenerating the array type if
7572 it will obviously be the same as T. */
7573 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7576 /* These checks should match the ones in grokdeclarator.
7580 The deduction may fail for any of the following reasons:
7582 -- Attempting to create an array with an element type that
7583 is void, a function type, or a reference type, or [DR337]
7584 an abstract class type. */
7585 if (TREE_CODE (type) == VOID_TYPE
7586 || TREE_CODE (type) == FUNCTION_TYPE
7587 || TREE_CODE (type) == REFERENCE_TYPE)
7589 if (complain & tf_error)
7590 error ("creating array of %qT", type);
7591 return error_mark_node;
7593 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7595 if (complain & tf_error)
7596 error ("creating array of %qT, which is an abstract class type",
7598 return error_mark_node;
7601 r = build_cplus_array_type (type, domain);
7608 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7609 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7611 if (e1 == error_mark_node || e2 == error_mark_node)
7612 return error_mark_node;
7614 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7620 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7621 if (e == error_mark_node)
7622 return error_mark_node;
7624 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7629 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7630 in_decl, /*entering_scope=*/1);
7631 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7634 if (ctx == error_mark_node || f == error_mark_node)
7635 return error_mark_node;
7637 if (!IS_AGGR_TYPE (ctx))
7639 if (complain & tf_error)
7640 error ("%qT is not a class, struct, or union type", ctx);
7641 return error_mark_node;
7643 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7645 /* Normally, make_typename_type does not require that the CTX
7646 have complete type in order to allow things like:
7648 template <class T> struct S { typename S<T>::X Y; };
7650 But, such constructs have already been resolved by this
7651 point, so here CTX really should have complete type, unless
7652 it's a partial instantiation. */
7653 ctx = complete_type (ctx);
7654 if (!COMPLETE_TYPE_P (ctx))
7656 if (complain & tf_error)
7657 cxx_incomplete_type_error (NULL_TREE, ctx);
7658 return error_mark_node;
7662 f = make_typename_type (ctx, f, typename_type,
7663 (complain & tf_error) | tf_keep_type_decl);
7664 if (f == error_mark_node)
7666 if (TREE_CODE (f) == TYPE_DECL)
7668 complain |= tf_ignore_bad_quals;
7672 if (TREE_CODE (f) != TYPENAME_TYPE)
7674 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7675 error ("%qT resolves to %qT, which is not an enumeration type",
7677 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7678 error ("%qT resolves to %qT, which is is not a class type",
7682 return cp_build_qualified_type_real
7683 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7686 case UNBOUND_CLASS_TEMPLATE:
7688 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7689 in_decl, /*entering_scope=*/1);
7690 tree name = TYPE_IDENTIFIER (t);
7691 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7693 if (ctx == error_mark_node || name == error_mark_node)
7694 return error_mark_node;
7697 parm_list = tsubst_template_parms (parm_list, args, complain);
7698 return make_unbound_class_template (ctx, name, parm_list, complain);
7708 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7709 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
7710 /*integral_constant_expression_p=*/false);
7711 if (e1 == error_mark_node || e2 == error_mark_node)
7712 return error_mark_node;
7714 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7719 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7720 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7721 if (e1 == error_mark_node || e2 == error_mark_node)
7722 return error_mark_node;
7724 return build_qualified_name (/*type=*/NULL_TREE,
7725 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
7732 type = finish_typeof (tsubst_expr
7733 (TYPEOF_TYPE_EXPR (t), args,
7735 /*integral_constant_expression_p=*/false));
7736 return cp_build_qualified_type_real (type,
7738 | cp_type_quals (type),
7743 sorry ("use of %qs in template",
7744 tree_code_name [(int) TREE_CODE (t)]);
7745 return error_mark_node;
7749 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7750 type of the expression on the left-hand side of the "." or "->"
7754 tsubst_baselink (tree baselink, tree object_type,
7755 tree args, tsubst_flags_t complain, tree in_decl)
7758 tree qualifying_scope;
7761 tree template_args = 0;
7762 bool template_id_p = false;
7764 /* A baselink indicates a function from a base class. The
7765 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7766 non-dependent types; otherwise, the lookup could not have
7767 succeeded. However, they may indicate bases of the template
7768 class, rather than the instantiated class.
7770 In addition, lookups that were not ambiguous before may be
7771 ambiguous now. Therefore, we perform the lookup again. */
7772 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7773 fns = BASELINK_FUNCTIONS (baselink);
7774 optype = BASELINK_OPTYPE (baselink);
7775 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7777 template_id_p = true;
7778 template_args = TREE_OPERAND (fns, 1);
7779 fns = TREE_OPERAND (fns, 0);
7781 template_args = tsubst_template_args (template_args, args,
7784 name = DECL_NAME (get_first_fn (fns));
7785 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7787 /* If lookup found a single function, mark it as used at this
7788 point. (If it lookup found multiple functions the one selected
7789 later by overload resolution will be marked as used at that
7791 if (BASELINK_P (baselink))
7792 fns = BASELINK_FUNCTIONS (baselink);
7793 if (!template_id_p && !really_overloaded_fn (fns))
7794 mark_used (OVL_CURRENT (fns));
7796 /* Add back the template arguments, if present. */
7797 if (BASELINK_P (baselink) && template_id_p)
7798 BASELINK_FUNCTIONS (baselink)
7799 = build_nt (TEMPLATE_ID_EXPR,
7800 BASELINK_FUNCTIONS (baselink),
7802 /* Update the conversion operator type. */
7803 BASELINK_OPTYPE (baselink)
7804 = tsubst (optype, args, complain, in_decl);
7807 object_type = current_class_type;
7808 return adjust_result_of_qualified_name_lookup (baselink,
7813 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7814 true if the qualified-id will be a postfix-expression in-and-of
7815 itself; false if more of the postfix-expression follows the
7816 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7820 tsubst_qualified_id (tree qualified_id, tree args,
7821 tsubst_flags_t complain, tree in_decl,
7822 bool done, bool address_p)
7830 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7832 /* Figure out what name to look up. */
7833 name = TREE_OPERAND (qualified_id, 1);
7834 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7837 template_args = TREE_OPERAND (name, 1);
7839 template_args = tsubst_template_args (template_args, args,
7841 name = TREE_OPERAND (name, 0);
7845 is_template = false;
7846 template_args = NULL_TREE;
7849 /* Substitute into the qualifying scope. When there are no ARGS, we
7850 are just trying to simplify a non-dependent expression. In that
7851 case the qualifying scope may be dependent, and, in any case,
7852 substituting will not help. */
7853 scope = TREE_OPERAND (qualified_id, 0);
7856 scope = tsubst (scope, args, complain, in_decl);
7857 expr = tsubst_copy (name, args, complain, in_decl);
7862 if (dependent_type_p (scope))
7863 return build_qualified_name (/*type=*/NULL_TREE,
7865 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
7867 if (!BASELINK_P (name) && !DECL_P (expr))
7869 if (TREE_CODE (expr) == BIT_NOT_EXPR)
7870 /* If this were actually a destructor call, it would have been
7871 parsed as such by the parser. */
7872 expr = error_mark_node;
7874 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7875 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7876 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7878 if (complain & tf_error)
7880 error ("dependent-name %qE is parsed as a non-type, but "
7881 "instantiation yields a type", qualified_id);
7882 inform ("say %<typename %E%> if a type is meant", qualified_id);
7884 return error_mark_node;
7890 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7892 /* Remember that there was a reference to this entity. */
7896 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7898 if (complain & tf_error)
7899 qualified_name_lookup_error (scope,
7900 TREE_OPERAND (qualified_id, 1),
7902 return error_mark_node;
7906 expr = lookup_template_function (expr, template_args);
7908 if (expr == error_mark_node && complain & tf_error)
7909 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7911 else if (TYPE_P (scope))
7913 expr = (adjust_result_of_qualified_name_lookup
7914 (expr, scope, current_class_type));
7915 expr = (finish_qualified_id_expr
7916 (scope, expr, done, address_p,
7917 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
7918 /*template_arg_p=*/false));
7921 /* Expressions do not generally have reference type. */
7922 if (TREE_CODE (expr) != SCOPE_REF
7923 /* However, if we're about to form a pointer-to-member, we just
7924 want the referenced member referenced. */
7925 && TREE_CODE (expr) != OFFSET_REF)
7926 expr = convert_from_reference (expr);
7931 /* Like tsubst, but deals with expressions. This function just replaces
7932 template parms; to finish processing the resultant expression, use
7936 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7938 enum tree_code code;
7941 if (t == NULL_TREE || t == error_mark_node)
7944 code = TREE_CODE (t);
7949 r = retrieve_local_specialization (t);
7950 gcc_assert (r != NULL);
7959 if (DECL_TEMPLATE_PARM_P (t))
7960 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7961 /* There is no need to substitute into namespace-scope
7963 if (DECL_NAMESPACE_SCOPE_P (t))
7965 /* If ARGS is NULL, then T is known to be non-dependent. */
7966 if (args == NULL_TREE)
7967 return integral_constant_value (t);
7969 /* Unfortunately, we cannot just call lookup_name here.
7972 template <int I> int f() {
7974 struct S { void g() { E e = a; } };
7977 When we instantiate f<7>::S::g(), say, lookup_name is not
7978 clever enough to find f<7>::a. */
7980 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7981 /*entering_scope=*/0);
7983 for (v = TYPE_VALUES (enum_type);
7986 if (TREE_PURPOSE (v) == DECL_NAME (t))
7987 return TREE_VALUE (v);
7989 /* We didn't find the name. That should never happen; if
7990 name-lookup found it during preliminary parsing, we
7991 should find it again here during instantiation. */
7997 if (DECL_CONTEXT (t))
8001 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
8002 /*entering_scope=*/1);
8003 if (ctx != DECL_CONTEXT (t))
8005 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
8008 if (complain & tf_error)
8009 error ("using invalid field %qD", t);
8010 return error_mark_node;
8020 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
8021 || local_variable_p (t))
8022 t = tsubst (t, args, complain, in_decl);
8027 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
8030 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
8031 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
8032 args, complain, in_decl);
8033 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
8034 return tsubst (t, args, complain, in_decl);
8035 else if (DECL_CLASS_SCOPE_P (t)
8036 && uses_template_parms (DECL_CONTEXT (t)))
8038 /* Template template argument like the following example need
8041 template <template <class> class TT> struct C {};
8042 template <class T> struct D {
8043 template <class U> struct E {};
8048 We are processing the template argument `E' in #1 for
8049 the template instantiation #2. Originally, `E' is a
8050 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
8051 have to substitute this with one having context `D<int>'. */
8053 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
8054 return lookup_field (context, DECL_NAME(t), 0, false);
8057 /* Ordinary template template argument. */
8061 case REINTERPRET_CAST_EXPR:
8062 case CONST_CAST_EXPR:
8063 case STATIC_CAST_EXPR:
8064 case DYNAMIC_CAST_EXPR:
8067 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
8068 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
8072 case TRUTH_NOT_EXPR:
8075 case UNARY_PLUS_EXPR: /* Unary + */
8084 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
8085 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
8092 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
8093 name = TREE_OPERAND (t, 1);
8094 if (TREE_CODE (name) == BIT_NOT_EXPR)
8096 name = tsubst_copy (TREE_OPERAND (name, 0), args,
8098 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
8100 else if (TREE_CODE (name) == SCOPE_REF
8101 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
8103 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
8105 name = TREE_OPERAND (name, 1);
8106 name = tsubst_copy (TREE_OPERAND (name, 0), args,
8108 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
8109 name = build_qualified_name (/*type=*/NULL_TREE,
8111 /*template_p=*/false);
8113 else if (TREE_CODE (name) == BASELINK)
8114 name = tsubst_baselink (name,
8115 non_reference (TREE_TYPE (object)),
8119 name = tsubst_copy (name, args, complain, in_decl);
8120 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
8126 case TRUNC_DIV_EXPR:
8128 case FLOOR_DIV_EXPR:
8129 case ROUND_DIV_EXPR:
8130 case EXACT_DIV_EXPR:
8134 case TRUNC_MOD_EXPR:
8135 case FLOOR_MOD_EXPR:
8136 case TRUTH_ANDIF_EXPR:
8137 case TRUTH_ORIF_EXPR:
8138 case TRUTH_AND_EXPR:
8155 case PREDECREMENT_EXPR:
8156 case PREINCREMENT_EXPR:
8157 case POSTDECREMENT_EXPR:
8158 case POSTINCREMENT_EXPR:
8160 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8161 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
8164 return build_qualified_name (/*type=*/NULL_TREE,
8165 tsubst_copy (TREE_OPERAND (t, 0),
8166 args, complain, in_decl),
8167 tsubst_copy (TREE_OPERAND (t, 1),
8168 args, complain, in_decl),
8169 QUALIFIED_NAME_IS_TEMPLATE (t));
8174 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8175 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
8176 NULL_TREE, NULL_TREE);
8179 return build_nt (code,
8180 tsubst_copy (TREE_OPERAND (t, 0), args,
8182 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
8188 case PSEUDO_DTOR_EXPR:
8191 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8192 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
8193 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
8194 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8201 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8202 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
8203 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
8204 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
8211 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8212 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
8213 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
8214 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
8218 case TEMPLATE_ID_EXPR:
8220 /* Substituted template arguments */
8221 tree fn = TREE_OPERAND (t, 0);
8222 tree targs = TREE_OPERAND (t, 1);
8224 fn = tsubst_copy (fn, args, complain, in_decl);
8226 targs = tsubst_template_args (targs, args, complain, in_decl);
8228 return lookup_template_function (fn, targs);
8233 tree purpose, value, chain;
8235 if (t == void_list_node)
8238 purpose = TREE_PURPOSE (t);
8240 purpose = tsubst_copy (purpose, args, complain, in_decl);
8241 value = TREE_VALUE (t);
8243 value = tsubst_copy (value, args, complain, in_decl);
8244 chain = TREE_CHAIN (t);
8245 if (chain && chain != void_type_node)
8246 chain = tsubst_copy (chain, args, complain, in_decl);
8247 if (purpose == TREE_PURPOSE (t)
8248 && value == TREE_VALUE (t)
8249 && chain == TREE_CHAIN (t))
8251 return tree_cons (purpose, value, chain);
8258 case TEMPLATE_TYPE_PARM:
8259 case TEMPLATE_TEMPLATE_PARM:
8260 case BOUND_TEMPLATE_TEMPLATE_PARM:
8261 case TEMPLATE_PARM_INDEX:
8263 case REFERENCE_TYPE:
8269 case UNBOUND_CLASS_TEMPLATE:
8272 return tsubst (t, args, complain, in_decl);
8274 case IDENTIFIER_NODE:
8275 if (IDENTIFIER_TYPENAME_P (t))
8277 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8278 return mangle_conv_op_name_for_type (new_type);
8284 /* This is handled by tsubst_copy_and_build. */
8288 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8290 tsubst (TREE_TYPE (t), args, complain, in_decl));
8292 case CLEANUP_POINT_EXPR:
8293 /* We shouldn't have built any of these during initial template
8294 generation. Instead, they should be built during instantiation
8295 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8299 mark_used (TREE_OPERAND (t, 1));
8307 /* Like tsubst_copy, but specifically for OpenMP clauses. */
8310 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
8313 tree new_clauses = NULL, nc, oc;
8315 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
8317 nc = copy_node (oc);
8318 OMP_CLAUSE_CHAIN (nc) = new_clauses;
8321 switch (OMP_CLAUSE_CODE (nc))
8323 case OMP_CLAUSE_PRIVATE:
8324 case OMP_CLAUSE_SHARED:
8325 case OMP_CLAUSE_FIRSTPRIVATE:
8326 case OMP_CLAUSE_LASTPRIVATE:
8327 case OMP_CLAUSE_REDUCTION:
8328 case OMP_CLAUSE_COPYIN:
8329 case OMP_CLAUSE_COPYPRIVATE:
8331 case OMP_CLAUSE_NUM_THREADS:
8332 case OMP_CLAUSE_SCHEDULE:
8333 OMP_CLAUSE_OPERAND (nc, 0)
8334 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
8335 in_decl, /*integral_constant_expression_p=*/false);
8337 case OMP_CLAUSE_NOWAIT:
8338 case OMP_CLAUSE_ORDERED:
8339 case OMP_CLAUSE_DEFAULT:
8346 return finish_omp_clauses (nreverse (new_clauses));
8349 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
8352 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
8355 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
8357 tree purpose, value, chain;
8362 if (TREE_CODE (t) != TREE_LIST)
8363 return tsubst_copy_and_build (t, args, complain, in_decl,
8364 /*function_p=*/false,
8365 /*integral_constant_expression_p=*/false);
8367 if (t == void_list_node)
8370 purpose = TREE_PURPOSE (t);
8372 purpose = RECUR (purpose);
8373 value = TREE_VALUE (t);
8375 value = RECUR (value);
8376 chain = TREE_CHAIN (t);
8377 if (chain && chain != void_type_node)
8378 chain = RECUR (chain);
8379 return tree_cons (purpose, value, chain);
8383 /* Like tsubst_copy for expressions, etc. but also does semantic
8387 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
8388 bool integral_constant_expression_p)
8390 #define RECUR(NODE) \
8391 tsubst_expr ((NODE), args, complain, in_decl, \
8392 integral_constant_expression_p)
8396 if (t == NULL_TREE || t == error_mark_node)
8399 if (EXPR_HAS_LOCATION (t))
8400 input_location = EXPR_LOCATION (t);
8401 if (STATEMENT_CODE_P (TREE_CODE (t)))
8402 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8404 switch (TREE_CODE (t))
8406 case STATEMENT_LIST:
8408 tree_stmt_iterator i;
8409 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8410 RECUR (tsi_stmt (i));
8414 case CTOR_INITIALIZER:
8415 finish_mem_initializers (tsubst_initializer_list
8416 (TREE_OPERAND (t, 0), args));
8420 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
8424 tmp = RECUR (EXPR_STMT_EXPR (t));
8425 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8426 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8428 finish_expr_stmt (tmp);
8432 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
8440 decl = DECL_EXPR_DECL (t);
8441 if (TREE_CODE (decl) == LABEL_DECL)
8442 finish_label_decl (DECL_NAME (decl));
8443 else if (TREE_CODE (decl) == USING_DECL)
8445 tree scope = USING_DECL_SCOPE (decl);
8446 tree name = DECL_NAME (decl);
8449 scope = RECUR (scope);
8450 decl = lookup_qualified_name (scope, name,
8451 /*is_type_p=*/false,
8452 /*complain=*/false);
8453 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8454 qualified_name_lookup_error (scope, name, decl);
8456 do_local_using_decl (decl, scope, name);
8460 init = DECL_INITIAL (decl);
8461 decl = tsubst (decl, args, complain, in_decl);
8462 if (decl != error_mark_node)
8464 /* By marking the declaration as instantiated, we avoid
8465 trying to instantiate it. Since instantiate_decl can't
8466 handle local variables, and since we've already done
8467 all that needs to be done, that's the right thing to
8469 if (TREE_CODE (decl) == VAR_DECL)
8470 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8471 if (TREE_CODE (decl) == VAR_DECL
8472 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8473 /* Anonymous aggregates are a special case. */
8474 finish_anon_union (decl);
8477 maybe_push_decl (decl);
8478 if (TREE_CODE (decl) == VAR_DECL
8479 && DECL_PRETTY_FUNCTION_P (decl))
8481 /* For __PRETTY_FUNCTION__ we have to adjust the
8483 const char *const name
8484 = cxx_printable_name (current_function_decl, 2);
8485 init = cp_fname_init (name, &TREE_TYPE (decl));
8488 init = RECUR (init);
8489 finish_decl (decl, init, NULL_TREE);
8494 /* A DECL_EXPR can also be used as an expression, in the condition
8495 clause of an if/for/while construct. */
8500 stmt = begin_for_stmt ();
8501 RECUR (FOR_INIT_STMT (t));
8502 finish_for_init_stmt (stmt);
8503 tmp = RECUR (FOR_COND (t));
8504 finish_for_cond (tmp, stmt);
8505 tmp = RECUR (FOR_EXPR (t));
8506 finish_for_expr (tmp, stmt);
8507 RECUR (FOR_BODY (t));
8508 finish_for_stmt (stmt);
8512 stmt = begin_while_stmt ();
8513 tmp = RECUR (WHILE_COND (t));
8514 finish_while_stmt_cond (tmp, stmt);
8515 RECUR (WHILE_BODY (t));
8516 finish_while_stmt (stmt);
8520 stmt = begin_do_stmt ();
8521 RECUR (DO_BODY (t));
8522 finish_do_body (stmt);
8523 tmp = RECUR (DO_COND (t));
8524 finish_do_stmt (tmp, stmt);
8528 stmt = begin_if_stmt ();
8529 tmp = RECUR (IF_COND (t));
8530 finish_if_stmt_cond (tmp, stmt);
8531 RECUR (THEN_CLAUSE (t));
8532 finish_then_clause (stmt);
8534 if (ELSE_CLAUSE (t))
8536 begin_else_clause (stmt);
8537 RECUR (ELSE_CLAUSE (t));
8538 finish_else_clause (stmt);
8541 finish_if_stmt (stmt);
8545 if (BIND_EXPR_BODY_BLOCK (t))
8546 stmt = begin_function_body ();
8548 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8549 ? BCS_TRY_BLOCK : 0);
8551 RECUR (BIND_EXPR_BODY (t));
8553 if (BIND_EXPR_BODY_BLOCK (t))
8554 finish_function_body (stmt);
8556 finish_compound_stmt (stmt);
8560 finish_break_stmt ();
8564 finish_continue_stmt ();
8568 stmt = begin_switch_stmt ();
8569 tmp = RECUR (SWITCH_STMT_COND (t));
8570 finish_switch_cond (tmp, stmt);
8571 RECUR (SWITCH_STMT_BODY (t));
8572 finish_switch_stmt (stmt);
8575 case CASE_LABEL_EXPR:
8576 finish_case_label (RECUR (CASE_LOW (t)),
8577 RECUR (CASE_HIGH (t)));
8581 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8585 tmp = GOTO_DESTINATION (t);
8586 if (TREE_CODE (tmp) != LABEL_DECL)
8587 /* Computed goto's must be tsubst'd into. On the other hand,
8588 non-computed gotos must not be; the identifier in question
8589 will have no binding. */
8592 tmp = DECL_NAME (tmp);
8593 finish_goto_stmt (tmp);
8597 tmp = finish_asm_stmt
8598 (ASM_VOLATILE_P (t),
8599 RECUR (ASM_STRING (t)),
8600 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
8601 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
8602 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl));
8604 tree asm_expr = tmp;
8605 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8606 asm_expr = TREE_OPERAND (asm_expr, 0);
8607 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8614 stmt = begin_try_block ();
8615 RECUR (TRY_STMTS (t));
8616 finish_cleanup_try_block (stmt);
8617 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
8621 tree compound_stmt = NULL_TREE;
8623 if (FN_TRY_BLOCK_P (t))
8624 stmt = begin_function_try_block (&compound_stmt);
8626 stmt = begin_try_block ();
8628 RECUR (TRY_STMTS (t));
8630 if (FN_TRY_BLOCK_P (t))
8631 finish_function_try_block (stmt);
8633 finish_try_block (stmt);
8635 RECUR (TRY_HANDLERS (t));
8636 if (FN_TRY_BLOCK_P (t))
8637 finish_function_handler_sequence (stmt, compound_stmt);
8639 finish_handler_sequence (stmt);
8645 tree decl = HANDLER_PARMS (t);
8649 decl = tsubst (decl, args, complain, in_decl);
8650 /* Prevent instantiate_decl from trying to instantiate
8651 this variable. We've already done all that needs to be
8653 if (decl != error_mark_node)
8654 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8656 stmt = begin_handler ();
8657 finish_handler_parms (decl, stmt);
8658 RECUR (HANDLER_BODY (t));
8659 finish_handler (stmt);
8664 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8668 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
8669 args, complain, in_decl);
8670 stmt = begin_omp_parallel ();
8671 RECUR (OMP_PARALLEL_BODY (t));
8672 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
8673 = OMP_PARALLEL_COMBINED (t);
8678 tree clauses, decl, init, cond, incr, body, pre_body;
8680 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
8681 args, complain, in_decl);
8682 init = OMP_FOR_INIT (t);
8683 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
8684 decl = RECUR (TREE_OPERAND (init, 0));
8685 init = RECUR (TREE_OPERAND (init, 1));
8686 cond = RECUR (OMP_FOR_COND (t));
8687 incr = RECUR (OMP_FOR_INCR (t));
8689 stmt = begin_omp_structured_block ();
8691 pre_body = push_stmt_list ();
8692 RECUR (OMP_FOR_PRE_BODY (t));
8693 pre_body = pop_stmt_list (pre_body);
8695 body = push_stmt_list ();
8696 RECUR (OMP_FOR_BODY (t));
8697 body = pop_stmt_list (body);
8699 t = finish_omp_for (EXPR_LOCATION (t), decl, init, cond, incr, body,
8702 OMP_FOR_CLAUSES (t) = clauses;
8704 add_stmt (finish_omp_structured_block (stmt));
8710 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
8711 stmt = push_stmt_list ();
8712 RECUR (OMP_BODY (t));
8713 stmt = pop_stmt_list (stmt);
8716 OMP_BODY (t) = stmt;
8717 OMP_CLAUSES (t) = tmp;
8725 stmt = push_stmt_list ();
8726 RECUR (OMP_BODY (t));
8727 stmt = pop_stmt_list (stmt);
8730 OMP_BODY (t) = stmt;
8737 op0 = RECUR (TREE_OPERAND (t, 0));
8738 op1 = RECUR (TREE_OPERAND (t, 1));
8739 finish_omp_atomic (OMP_ATOMIC_CODE (t), op0, op1);
8744 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8746 return tsubst_copy_and_build (t, args, complain, in_decl,
8747 /*function_p=*/false,
8748 integral_constant_expression_p);
8755 /* T is a postfix-expression that is not being used in a function
8756 call. Return the substituted version of T. */
8759 tsubst_non_call_postfix_expression (tree t, tree args,
8760 tsubst_flags_t complain,
8763 if (TREE_CODE (t) == SCOPE_REF)
8764 t = tsubst_qualified_id (t, args, complain, in_decl,
8765 /*done=*/false, /*address_p=*/false);
8767 t = tsubst_copy_and_build (t, args, complain, in_decl,
8768 /*function_p=*/false,
8769 /*integral_constant_expression_p=*/false);
8774 /* Like tsubst but deals with expressions and performs semantic
8775 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8778 tsubst_copy_and_build (tree t,
8780 tsubst_flags_t complain,
8783 bool integral_constant_expression_p)
8785 #define RECUR(NODE) \
8786 tsubst_copy_and_build (NODE, args, complain, in_decl, \
8787 /*function_p=*/false, \
8788 integral_constant_expression_p)
8792 if (t == NULL_TREE || t == error_mark_node)
8795 switch (TREE_CODE (t))
8800 case IDENTIFIER_NODE:
8804 bool non_integral_constant_expression_p;
8805 const char *error_msg;
8807 if (IDENTIFIER_TYPENAME_P (t))
8809 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8810 t = mangle_conv_op_name_for_type (new_type);
8813 /* Look up the name. */
8814 decl = lookup_name (t);
8816 /* By convention, expressions use ERROR_MARK_NODE to indicate
8817 failure, not NULL_TREE. */
8818 if (decl == NULL_TREE)
8819 decl = error_mark_node;
8821 decl = finish_id_expression (t, decl, NULL_TREE,
8823 integral_constant_expression_p,
8824 /*allow_non_integral_constant_expression_p=*/false,
8825 &non_integral_constant_expression_p,
8826 /*template_p=*/false,
8828 /*address_p=*/false,
8829 /*template_arg_p=*/false,
8833 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8834 decl = unqualified_name_lookup_error (decl);
8838 case TEMPLATE_ID_EXPR:
8841 tree template = RECUR (TREE_OPERAND (t, 0));
8842 tree targs = TREE_OPERAND (t, 1);
8845 targs = tsubst_template_args (targs, args, complain, in_decl);
8847 if (TREE_CODE (template) == COMPONENT_REF)
8849 object = TREE_OPERAND (template, 0);
8850 template = TREE_OPERAND (template, 1);
8854 template = lookup_template_function (template, targs);
8857 return build3 (COMPONENT_REF, TREE_TYPE (template),
8858 object, template, NULL_TREE);
8860 return baselink_for_fns (template);
8865 tree r = RECUR (TREE_OPERAND (t, 0));
8867 if (REFERENCE_REF_P (t))
8869 /* A type conversion to reference type will be enclosed in
8870 such an indirect ref, but the substitution of the cast
8871 will have also added such an indirect ref. */
8872 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8873 r = convert_from_reference (r);
8876 r = build_x_indirect_ref (r, "unary *");
8882 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8883 RECUR (TREE_OPERAND (t, 0)));
8886 case REINTERPRET_CAST_EXPR:
8887 case CONST_CAST_EXPR:
8888 case DYNAMIC_CAST_EXPR:
8889 case STATIC_CAST_EXPR:
8894 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8895 if (integral_constant_expression_p
8896 && !cast_valid_in_integral_constant_expression_p (type))
8898 error ("a cast to a type other than an integral or "
8899 "enumeration type cannot appear in a constant-expression");
8900 return error_mark_node;
8903 op = RECUR (TREE_OPERAND (t, 0));
8905 switch (TREE_CODE (t))
8908 return build_functional_cast (type, op);
8909 case REINTERPRET_CAST_EXPR:
8910 return build_reinterpret_cast (type, op);
8911 case CONST_CAST_EXPR:
8912 return build_const_cast (type, op);
8913 case DYNAMIC_CAST_EXPR:
8914 return build_dynamic_cast (type, op);
8915 case STATIC_CAST_EXPR:
8916 return build_static_cast (type, op);
8922 case POSTDECREMENT_EXPR:
8923 case POSTINCREMENT_EXPR:
8924 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8925 args, complain, in_decl);
8926 return build_x_unary_op (TREE_CODE (t), op1);
8928 case PREDECREMENT_EXPR:
8929 case PREINCREMENT_EXPR:
8933 case TRUTH_NOT_EXPR:
8934 case UNARY_PLUS_EXPR: /* Unary + */
8937 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8940 op1 = TREE_OPERAND (t, 0);
8941 if (TREE_CODE (op1) == SCOPE_REF)
8942 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8943 /*done=*/true, /*address_p=*/true);
8945 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8947 if (TREE_CODE (op1) == LABEL_DECL)
8948 return finish_label_address_expr (DECL_NAME (op1));
8949 return build_x_unary_op (ADDR_EXPR, op1);
8954 case TRUNC_DIV_EXPR:
8956 case FLOOR_DIV_EXPR:
8957 case ROUND_DIV_EXPR:
8958 case EXACT_DIV_EXPR:
8962 case TRUNC_MOD_EXPR:
8963 case FLOOR_MOD_EXPR:
8964 case TRUTH_ANDIF_EXPR:
8965 case TRUTH_ORIF_EXPR:
8966 case TRUTH_AND_EXPR:
8982 return build_x_binary_op
8984 RECUR (TREE_OPERAND (t, 0)),
8985 RECUR (TREE_OPERAND (t, 1)),
8986 /*overloaded_p=*/NULL);
8989 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8990 /*address_p=*/false);
8992 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8993 args, complain, in_decl);
8994 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8995 /*overloaded_p=*/NULL);
8999 op1 = TREE_OPERAND (t, 0);
9002 /* When there are no ARGS, we are trying to evaluate a
9003 non-dependent expression from the parser. Trying to do
9004 the substitutions may not work. */
9006 op1 = TREE_TYPE (op1);
9011 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
9012 /*function_p=*/false,
9013 /*integral_constant_expression_p=*/false);
9017 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
9019 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
9023 tree r = build_x_modify_expr
9024 (RECUR (TREE_OPERAND (t, 0)),
9025 TREE_CODE (TREE_OPERAND (t, 1)),
9026 RECUR (TREE_OPERAND (t, 2)));
9027 /* TREE_NO_WARNING must be set if either the expression was
9028 parenthesized or it uses an operator such as >>= rather
9029 than plain assignment. In the former case, it was already
9030 set and must be copied. In the latter case,
9031 build_x_modify_expr sets it and it must not be reset
9033 if (TREE_NO_WARNING (t))
9034 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
9039 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
9040 args, complain, in_decl);
9041 /* Remember that there was a reference to this entity. */
9044 return build_x_arrow (op1);
9048 (RECUR (TREE_OPERAND (t, 0)),
9049 RECUR (TREE_OPERAND (t, 1)),
9050 RECUR (TREE_OPERAND (t, 2)),
9051 RECUR (TREE_OPERAND (t, 3)),
9052 NEW_EXPR_USE_GLOBAL (t));
9055 return delete_sanity
9056 (RECUR (TREE_OPERAND (t, 0)),
9057 RECUR (TREE_OPERAND (t, 1)),
9058 DELETE_EXPR_USE_VEC (t),
9059 DELETE_EXPR_USE_GLOBAL (t));
9062 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
9063 RECUR (TREE_OPERAND (t, 1)));
9072 function = TREE_OPERAND (t, 0);
9073 /* When we parsed the expression, we determined whether or
9074 not Koenig lookup should be performed. */
9075 koenig_p = KOENIG_LOOKUP_P (t);
9076 if (TREE_CODE (function) == SCOPE_REF)
9079 function = tsubst_qualified_id (function, args, complain, in_decl,
9081 /*address_p=*/false);
9085 if (TREE_CODE (function) == COMPONENT_REF)
9087 tree op = TREE_OPERAND (function, 1);
9089 qualified_p = (TREE_CODE (op) == SCOPE_REF
9091 && BASELINK_QUALIFIED_P (op)));
9094 qualified_p = false;
9096 function = tsubst_copy_and_build (function, args, complain,
9099 integral_constant_expression_p);
9101 if (BASELINK_P (function))
9105 call_args = RECUR (TREE_OPERAND (t, 1));
9107 /* We do not perform argument-dependent lookup if normal
9108 lookup finds a non-function, in accordance with the
9109 expected resolution of DR 218. */
9111 && ((is_overloaded_fn (function)
9112 /* If lookup found a member function, the Koenig lookup is
9113 not appropriate, even if an unqualified-name was used
9114 to denote the function. */
9115 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
9116 || TREE_CODE (function) == IDENTIFIER_NODE))
9117 function = perform_koenig_lookup (function, call_args);
9119 if (TREE_CODE (function) == IDENTIFIER_NODE)
9121 unqualified_name_lookup_error (function);
9122 return error_mark_node;
9125 /* Remember that there was a reference to this entity. */
9126 if (DECL_P (function))
9127 mark_used (function);
9129 if (TREE_CODE (function) == OFFSET_REF)
9130 return build_offset_ref_call_from_tree (function, call_args);
9131 if (TREE_CODE (function) == COMPONENT_REF)
9133 if (!BASELINK_P (TREE_OPERAND (function, 1)))
9134 return finish_call_expr (function, call_args,
9135 /*disallow_virtual=*/false,
9136 /*koenig_p=*/false);
9138 return (build_new_method_call
9139 (TREE_OPERAND (function, 0),
9140 TREE_OPERAND (function, 1),
9141 call_args, NULL_TREE,
9142 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
9145 return finish_call_expr (function, call_args,
9146 /*disallow_virtual=*/qualified_p,
9151 return build_x_conditional_expr
9152 (RECUR (TREE_OPERAND (t, 0)),
9153 RECUR (TREE_OPERAND (t, 1)),
9154 RECUR (TREE_OPERAND (t, 2)));
9156 case PSEUDO_DTOR_EXPR:
9157 return finish_pseudo_destructor_expr
9158 (RECUR (TREE_OPERAND (t, 0)),
9159 RECUR (TREE_OPERAND (t, 1)),
9160 RECUR (TREE_OPERAND (t, 2)));
9164 tree purpose, value, chain;
9166 if (t == void_list_node)
9169 purpose = TREE_PURPOSE (t);
9171 purpose = RECUR (purpose);
9172 value = TREE_VALUE (t);
9174 value = RECUR (value);
9175 chain = TREE_CHAIN (t);
9176 if (chain && chain != void_type_node)
9177 chain = RECUR (chain);
9178 if (purpose == TREE_PURPOSE (t)
9179 && value == TREE_VALUE (t)
9180 && chain == TREE_CHAIN (t))
9182 return tree_cons (purpose, value, chain);
9191 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
9192 args, complain, in_decl);
9193 /* Remember that there was a reference to this entity. */
9194 if (DECL_P (object))
9196 object_type = TREE_TYPE (object);
9198 member = TREE_OPERAND (t, 1);
9199 if (BASELINK_P (member))
9200 member = tsubst_baselink (member,
9201 non_reference (TREE_TYPE (object)),
9202 args, complain, in_decl);
9203 else if (TREE_CODE (member) == BIT_NOT_EXPR
9204 && !TYPE_P (TREE_OPERAND (member, 0)))
9206 tree id = TREE_OPERAND (member, 0);
9207 id = make_typename_type (object_type, id, typename_type, complain);
9208 gcc_assert (TREE_CODE (id) != TYPENAME_TYPE);
9209 member = build_nt (BIT_NOT_EXPR, id);
9212 member = tsubst_copy (member, args, complain, in_decl);
9213 if (member == error_mark_node)
9214 return error_mark_node;
9216 if (object_type && !CLASS_TYPE_P (object_type))
9218 if (TREE_CODE (member) == BIT_NOT_EXPR)
9219 return finish_pseudo_destructor_expr (object,
9222 else if (TREE_CODE (member) == SCOPE_REF
9223 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
9224 return finish_pseudo_destructor_expr (object,
9228 else if (TREE_CODE (member) == SCOPE_REF
9229 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
9234 /* Lookup the template functions now that we know what the
9236 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
9237 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
9238 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
9239 /*is_type_p=*/false,
9240 /*complain=*/false);
9241 if (BASELINK_P (member))
9243 BASELINK_FUNCTIONS (member)
9244 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
9246 member = (adjust_result_of_qualified_name_lookup
9247 (member, BINFO_TYPE (BASELINK_BINFO (member)),
9252 qualified_name_lookup_error (object_type, tmpl, member);
9253 return error_mark_node;
9256 else if (TREE_CODE (member) == SCOPE_REF
9257 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
9258 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
9260 if (complain & tf_error)
9262 if (TYPE_P (TREE_OPERAND (member, 0)))
9263 error ("%qT is not a class or namespace",
9264 TREE_OPERAND (member, 0));
9266 error ("%qD is not a class or namespace",
9267 TREE_OPERAND (member, 0));
9269 return error_mark_node;
9271 else if (TREE_CODE (member) == FIELD_DECL)
9272 return finish_non_static_data_member (member, object, NULL_TREE);
9274 return finish_class_member_access_expr (object, member,
9275 /*template_p=*/false);
9280 (RECUR (TREE_OPERAND (t, 0)));
9284 VEC(constructor_elt,gc) *n;
9285 constructor_elt *ce;
9286 unsigned HOST_WIDE_INT idx;
9288 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9289 bool process_index_p;
9291 if (type == error_mark_node)
9292 return error_mark_node;
9294 /* digest_init will do the wrong thing if we let it. */
9295 if (type && TYPE_PTRMEMFUNC_P (type))
9298 /* We do not want to process the index of aggregate
9299 initializers as they are identifier nodes which will be
9300 looked up by digest_init. */
9301 process_index_p = !(type && IS_AGGR_TYPE (type));
9303 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
9304 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
9306 if (ce->index && process_index_p)
9307 ce->index = RECUR (ce->index);
9308 ce->value = RECUR (ce->value);
9311 r = build_constructor (NULL_TREE, n);
9312 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
9315 return digest_init (type, r);
9321 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
9322 if (TYPE_P (operand_0))
9323 return get_typeid (operand_0);
9324 return build_typeid (operand_0);
9334 tree r = tsubst_copy (t, args, complain, in_decl);
9336 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
9337 /* If the original type was a reference, we'll be wrapped in
9338 the appropriate INDIRECT_REF. */
9339 r = convert_from_reference (r);
9344 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
9345 tsubst_copy (TREE_TYPE (t), args, complain,
9349 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
9353 tree old_stmt_expr = cur_stmt_expr;
9354 tree stmt_expr = begin_stmt_expr ();
9356 cur_stmt_expr = stmt_expr;
9357 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
9358 integral_constant_expression_p);
9359 stmt_expr = finish_stmt_expr (stmt_expr, false);
9360 cur_stmt_expr = old_stmt_expr;
9366 t = tsubst_copy (t, args, complain, in_decl);
9367 /* As in finish_id_expression, we resolve enumeration constants
9368 to their underlying values. */
9369 if (TREE_CODE (t) == CONST_DECL)
9371 used_types_insert (TREE_TYPE (t));
9372 return DECL_INITIAL (t);
9377 /* Handle Objective-C++ constructs, if appropriate. */
9380 = objcp_tsubst_copy_and_build (t, args, complain,
9381 in_decl, /*function_p=*/false);
9385 return tsubst_copy (t, args, complain, in_decl);
9391 /* Verify that the instantiated ARGS are valid. For type arguments,
9392 make sure that the type's linkage is ok. For non-type arguments,
9393 make sure they are constants if they are integral or enumerations.
9394 Emit an error under control of COMPLAIN, and return TRUE on error. */
9397 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
9399 int ix, len = DECL_NTPARMS (tmpl);
9400 bool result = false;
9402 for (ix = 0; ix != len; ix++)
9404 tree t = TREE_VEC_ELT (args, ix);
9408 /* [basic.link]: A name with no linkage (notably, the name
9409 of a class or enumeration declared in a local scope)
9410 shall not be used to declare an entity with linkage.
9411 This implies that names with no linkage cannot be used as
9412 template arguments. */
9413 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
9417 /* DR 488 makes use of a type with no linkage cause
9418 type deduction to fail. */
9419 if (complain & tf_error)
9421 if (TYPE_ANONYMOUS_P (nt))
9422 error ("%qT is/uses anonymous type", t);
9424 error ("template argument for %qD uses local type %qT",
9429 /* In order to avoid all sorts of complications, we do not
9430 allow variably-modified types as template arguments. */
9431 else if (variably_modified_type_p (t, NULL_TREE))
9433 if (complain & tf_error)
9434 error ("%qT is a variably modified type", t);
9438 /* A non-type argument of integral or enumerated type must be a
9440 else if (TREE_TYPE (t)
9441 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
9442 && !TREE_CONSTANT (t))
9444 if (complain & tf_error)
9445 error ("integral expression %qE is not constant", t);
9449 if (result && (complain & tf_error))
9450 error (" trying to instantiate %qD", tmpl);
9454 /* Instantiate the indicated variable or function template TMPL with
9455 the template arguments in TARG_PTR. */
9458 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
9463 HOST_WIDE_INT saved_processing_template_decl;
9465 if (tmpl == error_mark_node)
9466 return error_mark_node;
9468 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
9470 /* If this function is a clone, handle it specially. */
9471 if (DECL_CLONED_FUNCTION_P (tmpl))
9476 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
9478 if (spec == error_mark_node)
9479 return error_mark_node;
9481 /* Look for the clone. */
9482 FOR_EACH_CLONE (clone, spec)
9483 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9485 /* We should always have found the clone by now. */
9490 /* Check to see if we already have this specialization. */
9491 spec = retrieve_specialization (tmpl, targ_ptr,
9492 /*class_specializations_p=*/false);
9493 if (spec != NULL_TREE)
9496 gen_tmpl = most_general_template (tmpl);
9497 if (tmpl != gen_tmpl)
9499 /* The TMPL is a partial instantiation. To get a full set of
9500 arguments we must add the arguments used to perform the
9501 partial instantiation. */
9502 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9505 /* Check to see if we already have this specialization. */
9506 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9507 /*class_specializations_p=*/false);
9508 if (spec != NULL_TREE)
9512 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9514 return error_mark_node;
9516 /* We are building a FUNCTION_DECL, during which the access of its
9517 parameters and return types have to be checked. However this
9518 FUNCTION_DECL which is the desired context for access checking
9519 is not built yet. We solve this chicken-and-egg problem by
9520 deferring all checks until we have the FUNCTION_DECL. */
9521 push_deferring_access_checks (dk_deferred);
9523 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
9524 (because, for example, we have encountered a non-dependent
9525 function call in the body of a template function and must now
9526 determine which of several overloaded functions will be called),
9527 within the instantiation itself we are not processing a
9529 saved_processing_template_decl = processing_template_decl;
9530 processing_template_decl = 0;
9531 /* Substitute template parameters to obtain the specialization. */
9532 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9533 targ_ptr, complain, gen_tmpl);
9534 processing_template_decl = saved_processing_template_decl;
9535 if (fndecl == error_mark_node)
9536 return error_mark_node;
9538 /* Now we know the specialization, compute access previously
9540 push_access_scope (fndecl);
9541 perform_deferred_access_checks ();
9542 pop_access_scope (fndecl);
9543 pop_deferring_access_checks ();
9545 /* The DECL_TI_TEMPLATE should always be the immediate parent
9546 template, not the most general template. */
9547 DECL_TI_TEMPLATE (fndecl) = tmpl;
9549 /* If we've just instantiated the main entry point for a function,
9550 instantiate all the alternate entry points as well. We do this
9551 by cloning the instantiation of the main entry point, not by
9552 instantiating the template clones. */
9553 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9554 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9559 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9560 arguments that are being used when calling it. TARGS is a vector
9561 into which the deduced template arguments are placed.
9563 Return zero for success, 2 for an incomplete match that doesn't resolve
9564 all the types, and 1 for complete failure. An error message will be
9565 printed only for an incomplete match.
9567 If FN is a conversion operator, or we are trying to produce a specific
9568 specialization, RETURN_TYPE is the return type desired.
9570 The EXPLICIT_TARGS are explicit template arguments provided via a
9573 The parameter STRICT is one of:
9576 We are deducing arguments for a function call, as in
9580 We are deducing arguments for a conversion function, as in
9584 We are deducing arguments when doing an explicit instantiation
9585 as in [temp.explicit], when determining an explicit specialization
9586 as in [temp.expl.spec], or when taking the address of a function
9587 template, as in [temp.deduct.funcaddr]. */
9590 fn_type_unification (tree fn,
9591 tree explicit_targs,
9595 unification_kind_t strict,
9602 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9604 fntype = TREE_TYPE (fn);
9609 The specified template arguments must match the template
9610 parameters in kind (i.e., type, nontype, template), and there
9611 must not be more arguments than there are parameters;
9612 otherwise type deduction fails.
9614 Nontype arguments must match the types of the corresponding
9615 nontype template parameters, or must be convertible to the
9616 types of the corresponding nontype parameters as specified in
9617 _temp.arg.nontype_, otherwise type deduction fails.
9619 All references in the function type of the function template
9620 to the corresponding template parameters are replaced by the
9621 specified template argument values. If a substitution in a
9622 template parameter or in the function type of the function
9623 template results in an invalid type, type deduction fails. */
9625 tree converted_args;
9628 if (explicit_targs == error_mark_node)
9632 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9633 explicit_targs, NULL_TREE, tf_none,
9634 /*require_all_args=*/false,
9635 /*use_default_args=*/false));
9636 if (converted_args == error_mark_node)
9639 /* Substitute the explicit args into the function type. This is
9640 necessary so that, for instance, explicitly declared function
9641 arguments can match null pointed constants. If we were given
9642 an incomplete set of explicit args, we must not do semantic
9643 processing during substitution as we could create partial
9645 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9646 processing_template_decl += incomplete;
9647 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9648 processing_template_decl -= incomplete;
9650 if (fntype == error_mark_node)
9653 /* Place the explicitly specified arguments in TARGS. */
9654 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9655 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9658 parms = TYPE_ARG_TYPES (fntype);
9659 /* Never do unification on the 'this' parameter. */
9660 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9661 parms = TREE_CHAIN (parms);
9665 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9666 args = tree_cons (NULL_TREE, return_type, args);
9669 /* We allow incomplete unification without an error message here
9670 because the standard doesn't seem to explicitly prohibit it. Our
9671 callers must be ready to deal with unification failures in any
9673 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9674 targs, parms, args, /*subr=*/0,
9678 /* All is well so far. Now, check:
9682 When all template arguments have been deduced, all uses of
9683 template parameters in nondeduced contexts are replaced with
9684 the corresponding deduced argument values. If the
9685 substitution results in an invalid type, as described above,
9686 type deduction fails. */
9687 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9694 /* Adjust types before performing type deduction, as described in
9695 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9696 sections are symmetric. PARM is the type of a function parameter
9697 or the return type of the conversion function. ARG is the type of
9698 the argument passed to the call, or the type of the value
9699 initialized with the result of the conversion function. */
9702 maybe_adjust_types_for_deduction (unification_kind_t strict,
9715 /* Swap PARM and ARG throughout the remainder of this
9716 function; the handling is precisely symmetric since PARM
9717 will initialize ARG rather than vice versa. */
9725 /* There is nothing to do in this case. */
9732 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9734 /* [temp.deduct.call]
9736 If P is not a reference type:
9738 --If A is an array type, the pointer type produced by the
9739 array-to-pointer standard conversion (_conv.array_) is
9740 used in place of A for type deduction; otherwise,
9742 --If A is a function type, the pointer type produced by
9743 the function-to-pointer standard conversion
9744 (_conv.func_) is used in place of A for type deduction;
9747 --If A is a cv-qualified type, the top level
9748 cv-qualifiers of A's type are ignored for type
9750 if (TREE_CODE (*arg) == ARRAY_TYPE)
9751 *arg = build_pointer_type (TREE_TYPE (*arg));
9752 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9753 *arg = build_pointer_type (*arg);
9755 *arg = TYPE_MAIN_VARIANT (*arg);
9758 /* [temp.deduct.call]
9760 If P is a cv-qualified type, the top level cv-qualifiers
9761 of P's type are ignored for type deduction. If P is a
9762 reference type, the type referred to by P is used for
9764 *parm = TYPE_MAIN_VARIANT (*parm);
9765 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9767 *parm = TREE_TYPE (*parm);
9768 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9771 /* DR 322. For conversion deduction, remove a reference type on parm
9772 too (which has been swapped into ARG). */
9773 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9774 *arg = TREE_TYPE (*arg);
9779 /* Most parms like fn_type_unification.
9781 If SUBR is 1, we're being called recursively (to unify the
9782 arguments of a function or method parameter of a function
9786 type_unification_real (tree tparms,
9791 unification_kind_t strict,
9796 int ntparms = TREE_VEC_LENGTH (tparms);
9798 int saw_undeduced = 0;
9801 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9802 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9803 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9804 gcc_assert (ntparms > 0);
9809 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9810 | UNIFY_ALLOW_DERIVED);
9814 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9818 sub_strict = UNIFY_ALLOW_NONE;
9829 while (parms && parms != void_list_node
9830 && args && args != void_list_node)
9832 parm = TREE_VALUE (parms);
9833 parms = TREE_CHAIN (parms);
9834 arg = TREE_VALUE (args);
9835 args = TREE_CHAIN (args);
9837 if (arg == error_mark_node)
9839 if (arg == unknown_type_node)
9840 /* We can't deduce anything from this, but we might get all the
9841 template args from other function args. */
9844 /* Conversions will be performed on a function argument that
9845 corresponds with a function parameter that contains only
9846 non-deducible template parameters and explicitly specified
9847 template parameters. */
9848 if (!uses_template_parms (parm))
9853 type = TREE_TYPE (arg);
9857 if (same_type_p (parm, type))
9859 if (strict != DEDUCE_EXACT
9860 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
9869 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9870 if (type_unknown_p (arg))
9872 /* [temp.deduct.type] A template-argument can be deduced from
9873 a pointer to function or pointer to member function
9874 argument if the set of overloaded functions does not
9875 contain function templates and at most one of a set of
9876 overloaded functions provides a unique match. */
9878 if (resolve_overloaded_unification
9879 (tparms, targs, parm, arg, strict, sub_strict)
9884 arg = TREE_TYPE (arg);
9885 if (arg == error_mark_node)
9890 int arg_strict = sub_strict;
9893 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9895 if (unify (tparms, targs, parm, arg, arg_strict))
9900 /* Fail if we've reached the end of the parm list, and more args
9901 are present, and the parm list isn't variadic. */
9902 if (args && args != void_list_node && parms == void_list_node)
9904 /* Fail if parms are left and they don't have default values. */
9905 if (parms && parms != void_list_node
9906 && TREE_PURPOSE (parms) == NULL_TREE)
9910 for (i = 0; i < ntparms; i++)
9911 if (!TREE_VEC_ELT (targs, i))
9915 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
9918 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9920 /* If this is an undeduced nontype parameter that depends on
9921 a type parameter, try another pass; its type may have been
9922 deduced from a later argument than the one from which
9923 this parameter can be deduced. */
9924 if (TREE_CODE (tparm) == PARM_DECL
9925 && uses_template_parms (TREE_TYPE (tparm))
9926 && !saw_undeduced++)
9935 /* Subroutine of type_unification_real. Args are like the variables at the
9936 call site. ARG is an overloaded function (or template-id); we try
9937 deducing template args from each of the overloads, and if only one
9938 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9941 resolve_overloaded_unification (tree tparms,
9945 unification_kind_t strict,
9948 tree tempargs = copy_node (targs);
9952 if (TREE_CODE (arg) == ADDR_EXPR)
9954 arg = TREE_OPERAND (arg, 0);
9960 if (TREE_CODE (arg) == COMPONENT_REF)
9961 /* Handle `&x' where `x' is some static or non-static member
9963 arg = TREE_OPERAND (arg, 1);
9965 if (TREE_CODE (arg) == OFFSET_REF)
9966 arg = TREE_OPERAND (arg, 1);
9968 /* Strip baselink information. */
9969 if (BASELINK_P (arg))
9970 arg = BASELINK_FUNCTIONS (arg);
9972 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9974 /* If we got some explicit template args, we need to plug them into
9975 the affected templates before we try to unify, in case the
9976 explicit args will completely resolve the templates in question. */
9978 tree expl_subargs = TREE_OPERAND (arg, 1);
9979 arg = TREE_OPERAND (arg, 0);
9981 for (; arg; arg = OVL_NEXT (arg))
9983 tree fn = OVL_CURRENT (arg);
9986 if (TREE_CODE (fn) != TEMPLATE_DECL)
9989 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9990 expl_subargs, /*check_ret=*/false);
9993 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9994 good += try_one_overload (tparms, targs, tempargs, parm,
9995 elem, strict, sub_strict, addr_p);
10001 gcc_assert (TREE_CODE (arg) == OVERLOAD
10002 || TREE_CODE (arg) == FUNCTION_DECL);
10004 for (; arg; arg = OVL_NEXT (arg))
10005 good += try_one_overload (tparms, targs, tempargs, parm,
10006 TREE_TYPE (OVL_CURRENT (arg)),
10007 strict, sub_strict, addr_p);
10010 /* [temp.deduct.type] A template-argument can be deduced from a pointer
10011 to function or pointer to member function argument if the set of
10012 overloaded functions does not contain function templates and at most
10013 one of a set of overloaded functions provides a unique match.
10015 So if we found multiple possibilities, we return success but don't
10016 deduce anything. */
10020 int i = TREE_VEC_LENGTH (targs);
10022 if (TREE_VEC_ELT (tempargs, i))
10023 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
10031 /* Subroutine of resolve_overloaded_unification; does deduction for a single
10032 overload. Fills TARGS with any deduced arguments, or error_mark_node if
10033 different overloads deduce different arguments for a given parm.
10034 ADDR_P is true if the expression for which deduction is being
10035 performed was of the form "& fn" rather than simply "fn".
10037 Returns 1 on success. */
10040 try_one_overload (tree tparms,
10045 unification_kind_t strict,
10053 /* [temp.deduct.type] A template-argument can be deduced from a pointer
10054 to function or pointer to member function argument if the set of
10055 overloaded functions does not contain function templates and at most
10056 one of a set of overloaded functions provides a unique match.
10058 So if this is a template, just return success. */
10060 if (uses_template_parms (arg))
10063 if (TREE_CODE (arg) == METHOD_TYPE)
10064 arg = build_ptrmemfunc_type (build_pointer_type (arg));
10066 arg = build_pointer_type (arg);
10068 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
10070 /* We don't copy orig_targs for this because if we have already deduced
10071 some template args from previous args, unify would complain when we
10072 try to deduce a template parameter for the same argument, even though
10073 there isn't really a conflict. */
10074 nargs = TREE_VEC_LENGTH (targs);
10075 tempargs = make_tree_vec (nargs);
10077 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
10080 /* First make sure we didn't deduce anything that conflicts with
10081 explicitly specified args. */
10082 for (i = nargs; i--; )
10084 tree elt = TREE_VEC_ELT (tempargs, i);
10085 tree oldelt = TREE_VEC_ELT (orig_targs, i);
10089 else if (uses_template_parms (elt))
10090 /* Since we're unifying against ourselves, we will fill in
10091 template args used in the function parm list with our own
10092 template parms. Discard them. */
10093 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
10094 else if (oldelt && !template_args_equal (oldelt, elt))
10098 for (i = nargs; i--; )
10100 tree elt = TREE_VEC_ELT (tempargs, i);
10103 TREE_VEC_ELT (targs, i) = elt;
10109 /* PARM is a template class (perhaps with unbound template
10110 parameters). ARG is a fully instantiated type. If ARG can be
10111 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
10112 TARGS are as for unify. */
10115 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
10117 tree copy_of_targs;
10119 if (!CLASSTYPE_TEMPLATE_INFO (arg)
10120 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
10121 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
10124 /* We need to make a new template argument vector for the call to
10125 unify. If we used TARGS, we'd clutter it up with the result of
10126 the attempted unification, even if this class didn't work out.
10127 We also don't want to commit ourselves to all the unifications
10128 we've already done, since unification is supposed to be done on
10129 an argument-by-argument basis. In other words, consider the
10130 following pathological case:
10132 template <int I, int J, int K>
10135 template <int I, int J>
10136 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
10138 template <int I, int J, int K>
10139 void f(S<I, J, K>, S<I, I, I>);
10148 Now, by the time we consider the unification involving `s2', we
10149 already know that we must have `f<0, 0, 0>'. But, even though
10150 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
10151 because there are two ways to unify base classes of S<0, 1, 2>
10152 with S<I, I, I>. If we kept the already deduced knowledge, we
10153 would reject the possibility I=1. */
10154 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
10156 /* If unification failed, we're done. */
10157 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
10158 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
10164 /* Given a template type PARM and a class type ARG, find the unique
10165 base type in ARG that is an instance of PARM. We do not examine
10166 ARG itself; only its base-classes. If there is not exactly one
10167 appropriate base class, return NULL_TREE. PARM may be the type of
10168 a partial specialization, as well as a plain template type. Used
10172 get_template_base (tree tparms, tree targs, tree parm, tree arg)
10174 tree rval = NULL_TREE;
10177 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
10179 binfo = TYPE_BINFO (complete_type (arg));
10181 /* The type could not be completed. */
10184 /* Walk in inheritance graph order. The search order is not
10185 important, and this avoids multiple walks of virtual bases. */
10186 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
10188 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
10192 /* If there is more than one satisfactory baseclass, then:
10196 If they yield more than one possible deduced A, the type
10200 if (rval && !same_type_p (r, rval))
10210 /* Returns the level of DECL, which declares a template parameter. */
10213 template_decl_level (tree decl)
10215 switch (TREE_CODE (decl))
10218 case TEMPLATE_DECL:
10219 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
10222 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
10225 gcc_unreachable ();
10230 /* Decide whether ARG can be unified with PARM, considering only the
10231 cv-qualifiers of each type, given STRICT as documented for unify.
10232 Returns nonzero iff the unification is OK on that basis. */
10235 check_cv_quals_for_unify (int strict, tree arg, tree parm)
10237 int arg_quals = cp_type_quals (arg);
10238 int parm_quals = cp_type_quals (parm);
10240 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
10241 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
10243 /* Although a CVR qualifier is ignored when being applied to a
10244 substituted template parameter ([8.3.2]/1 for example), that
10245 does not apply during deduction [14.8.2.4]/1, (even though
10246 that is not explicitly mentioned, [14.8.2.4]/9 indicates
10247 this). Except when we're allowing additional CV qualifiers
10248 at the outer level [14.8.2.1]/3,1st bullet. */
10249 if ((TREE_CODE (arg) == REFERENCE_TYPE
10250 || TREE_CODE (arg) == FUNCTION_TYPE
10251 || TREE_CODE (arg) == METHOD_TYPE)
10252 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
10255 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
10256 && (parm_quals & TYPE_QUAL_RESTRICT))
10260 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
10261 && (arg_quals & parm_quals) != parm_quals)
10264 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
10265 && (parm_quals & arg_quals) != arg_quals)
10271 /* Deduce the value of template parameters. TPARMS is the (innermost)
10272 set of template parameters to a template. TARGS is the bindings
10273 for those template parameters, as determined thus far; TARGS may
10274 include template arguments for outer levels of template parameters
10275 as well. PARM is a parameter to a template function, or a
10276 subcomponent of that parameter; ARG is the corresponding argument.
10277 This function attempts to match PARM with ARG in a manner
10278 consistent with the existing assignments in TARGS. If more values
10279 are deduced, then TARGS is updated.
10281 Returns 0 if the type deduction succeeds, 1 otherwise. The
10282 parameter STRICT is a bitwise or of the following flags:
10285 Require an exact match between PARM and ARG.
10286 UNIFY_ALLOW_MORE_CV_QUAL:
10287 Allow the deduced ARG to be more cv-qualified (by qualification
10288 conversion) than ARG.
10289 UNIFY_ALLOW_LESS_CV_QUAL:
10290 Allow the deduced ARG to be less cv-qualified than ARG.
10291 UNIFY_ALLOW_DERIVED:
10292 Allow the deduced ARG to be a template base class of ARG,
10293 or a pointer to a template base class of the type pointed to by
10295 UNIFY_ALLOW_INTEGER:
10296 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
10297 case for more information.
10298 UNIFY_ALLOW_OUTER_LEVEL:
10299 This is the outermost level of a deduction. Used to determine validity
10300 of qualification conversions. A valid qualification conversion must
10301 have const qualified pointers leading up to the inner type which
10302 requires additional CV quals, except at the outer level, where const
10303 is not required [conv.qual]. It would be normal to set this flag in
10304 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
10305 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
10306 This is the outermost level of a deduction, and PARM can be more CV
10307 qualified at this point.
10308 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
10309 This is the outermost level of a deduction, and PARM can be less CV
10310 qualified at this point. */
10313 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
10318 int strict_in = strict;
10320 /* I don't think this will do the right thing with respect to types.
10321 But the only case I've seen it in so far has been array bounds, where
10322 signedness is the only information lost, and I think that will be
10324 while (TREE_CODE (parm) == NOP_EXPR)
10325 parm = TREE_OPERAND (parm, 0);
10327 if (arg == error_mark_node)
10329 if (arg == unknown_type_node)
10330 /* We can't deduce anything from this, but we might get all the
10331 template args from other function args. */
10334 /* If PARM uses template parameters, then we can't bail out here,
10335 even if ARG == PARM, since we won't record unifications for the
10336 template parameters. We might need them if we're trying to
10337 figure out which of two things is more specialized. */
10338 if (arg == parm && !uses_template_parms (parm))
10341 /* Immediately reject some pairs that won't unify because of
10342 cv-qualification mismatches. */
10343 if (TREE_CODE (arg) == TREE_CODE (parm)
10345 /* It is the elements of the array which hold the cv quals of an array
10346 type, and the elements might be template type parms. We'll check
10347 when we recurse. */
10348 && TREE_CODE (arg) != ARRAY_TYPE
10349 /* We check the cv-qualifiers when unifying with template type
10350 parameters below. We want to allow ARG `const T' to unify with
10351 PARM `T' for example, when computing which of two templates
10352 is more specialized, for example. */
10353 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
10354 && !check_cv_quals_for_unify (strict_in, arg, parm))
10357 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
10358 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
10359 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
10360 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
10361 strict &= ~UNIFY_ALLOW_DERIVED;
10362 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
10363 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
10365 switch (TREE_CODE (parm))
10367 case TYPENAME_TYPE:
10369 case UNBOUND_CLASS_TEMPLATE:
10370 /* In a type which contains a nested-name-specifier, template
10371 argument values cannot be deduced for template parameters used
10372 within the nested-name-specifier. */
10375 case TEMPLATE_TYPE_PARM:
10376 case TEMPLATE_TEMPLATE_PARM:
10377 case BOUND_TEMPLATE_TEMPLATE_PARM:
10378 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10380 if (TEMPLATE_TYPE_LEVEL (parm)
10381 != template_decl_level (tparm))
10382 /* The PARM is not one we're trying to unify. Just check
10383 to see if it matches ARG. */
10384 return (TREE_CODE (arg) == TREE_CODE (parm)
10385 && same_type_p (parm, arg)) ? 0 : 1;
10386 idx = TEMPLATE_TYPE_IDX (parm);
10387 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
10388 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
10390 /* Check for mixed types and values. */
10391 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
10392 && TREE_CODE (tparm) != TYPE_DECL)
10393 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10394 && TREE_CODE (tparm) != TEMPLATE_DECL))
10397 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10399 /* ARG must be constructed from a template class or a template
10400 template parameter. */
10401 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
10402 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
10406 tree parmvec = TYPE_TI_ARGS (parm);
10407 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
10409 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
10412 /* The resolution to DR150 makes clear that default
10413 arguments for an N-argument may not be used to bind T
10414 to a template template parameter with fewer than N
10415 parameters. It is not safe to permit the binding of
10416 default arguments as an extension, as that may change
10417 the meaning of a conforming program. Consider:
10419 struct Dense { static const unsigned int dim = 1; };
10421 template <template <typename> class View,
10423 void operator+(float, View<Block> const&);
10425 template <typename Block,
10426 unsigned int Dim = Block::dim>
10427 struct Lvalue_proxy { operator float() const; };
10431 Lvalue_proxy<Dense> p;
10436 Here, if Lvalue_proxy is permitted to bind to View, then
10437 the global operator+ will be used; if they are not, the
10438 Lvalue_proxy will be converted to float. */
10439 if (coerce_template_parms (argtmplvec, parmvec,
10440 TYPE_TI_TEMPLATE (parm),
10442 /*require_all_args=*/true,
10443 /*use_default_args=*/false)
10444 == error_mark_node)
10447 /* Deduce arguments T, i from TT<T> or TT<i>.
10448 We check each element of PARMVEC and ARGVEC individually
10449 rather than the whole TREE_VEC since they can have
10450 different number of elements. */
10452 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
10454 if (unify (tparms, targs,
10455 TREE_VEC_ELT (parmvec, i),
10456 TREE_VEC_ELT (argvec, i),
10461 arg = TYPE_TI_TEMPLATE (arg);
10463 /* Fall through to deduce template name. */
10466 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10467 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10469 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
10471 /* Simple cases: Value already set, does match or doesn't. */
10472 if (targ != NULL_TREE && template_args_equal (targ, arg))
10479 /* If PARM is `const T' and ARG is only `int', we don't have
10480 a match unless we are allowing additional qualification.
10481 If ARG is `const int' and PARM is just `T' that's OK;
10482 that binds `const int' to `T'. */
10483 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10487 /* Consider the case where ARG is `const volatile int' and
10488 PARM is `const T'. Then, T should be `volatile int'. */
10489 arg = cp_build_qualified_type_real
10490 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10491 if (arg == error_mark_node)
10494 /* Simple cases: Value already set, does match or doesn't. */
10495 if (targ != NULL_TREE && same_type_p (targ, arg))
10500 /* Make sure that ARG is not a variable-sized array. (Note
10501 that were talking about variable-sized arrays (like
10502 `int[n]'), rather than arrays of unknown size (like
10503 `int[]').) We'll get very confused by such a type since
10504 the bound of the array will not be computable in an
10505 instantiation. Besides, such types are not allowed in
10506 ISO C++, so we can do as we please here. */
10507 if (variably_modified_type_p (arg, NULL_TREE))
10511 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
10514 case TEMPLATE_PARM_INDEX:
10515 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10516 if (tparm == error_mark_node)
10519 if (TEMPLATE_PARM_LEVEL (parm)
10520 != template_decl_level (tparm))
10521 /* The PARM is not one we're trying to unify. Just check
10522 to see if it matches ARG. */
10523 return !(TREE_CODE (arg) == TREE_CODE (parm)
10524 && cp_tree_equal (parm, arg));
10526 idx = TEMPLATE_PARM_IDX (parm);
10527 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
10530 return !cp_tree_equal (targ, arg);
10532 /* [temp.deduct.type] If, in the declaration of a function template
10533 with a non-type template-parameter, the non-type
10534 template-parameter is used in an expression in the function
10535 parameter-list and, if the corresponding template-argument is
10536 deduced, the template-argument type shall match the type of the
10537 template-parameter exactly, except that a template-argument
10538 deduced from an array bound may be of any integral type.
10539 The non-type parameter might use already deduced type parameters. */
10540 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10541 if (!TREE_TYPE (arg))
10542 /* Template-parameter dependent expression. Just accept it for now.
10543 It will later be processed in convert_template_argument. */
10545 else if (same_type_p (TREE_TYPE (arg), tparm))
10547 else if ((strict & UNIFY_ALLOW_INTEGER)
10548 && (TREE_CODE (tparm) == INTEGER_TYPE
10549 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10550 /* Convert the ARG to the type of PARM; the deduced non-type
10551 template argument must exactly match the types of the
10552 corresponding parameter. */
10553 arg = fold (build_nop (TREE_TYPE (parm), arg));
10554 else if (uses_template_parms (tparm))
10555 /* We haven't deduced the type of this parameter yet. Try again
10561 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
10566 /* A pointer-to-member constant can be unified only with
10567 another constant. */
10568 if (TREE_CODE (arg) != PTRMEM_CST)
10571 /* Just unify the class member. It would be useless (and possibly
10572 wrong, depending on the strict flags) to unify also
10573 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10574 arg refer to the same variable, even if through different
10575 classes. For instance:
10577 struct A { int x; };
10580 Unification of &A::x and &B::x must succeed. */
10581 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10582 PTRMEM_CST_MEMBER (arg), strict);
10587 if (TREE_CODE (arg) != POINTER_TYPE)
10590 /* [temp.deduct.call]
10592 A can be another pointer or pointer to member type that can
10593 be converted to the deduced A via a qualification
10594 conversion (_conv.qual_).
10596 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10597 This will allow for additional cv-qualification of the
10598 pointed-to types if appropriate. */
10600 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10601 /* The derived-to-base conversion only persists through one
10602 level of pointers. */
10603 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10605 return unify (tparms, targs, TREE_TYPE (parm),
10606 TREE_TYPE (arg), strict);
10609 case REFERENCE_TYPE:
10610 if (TREE_CODE (arg) != REFERENCE_TYPE)
10612 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10613 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10616 if (TREE_CODE (arg) != ARRAY_TYPE)
10618 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10619 != (TYPE_DOMAIN (arg) == NULL_TREE))
10621 if (TYPE_DOMAIN (parm) != NULL_TREE)
10626 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10627 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10629 /* Our representation of array types uses "N - 1" as the
10630 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10631 not an integer constant. */
10632 if (TREE_CODE (parm_max) == MINUS_EXPR)
10634 arg_max = fold_build2 (PLUS_EXPR,
10637 TREE_OPERAND (parm_max, 1));
10638 parm_max = TREE_OPERAND (parm_max, 0);
10641 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10644 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10645 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10652 case ENUMERAL_TYPE:
10654 if (TREE_CODE (arg) != TREE_CODE (parm))
10657 /* We have already checked cv-qualification at the top of the
10659 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10662 /* As far as unification is concerned, this wins. Later checks
10663 will invalidate it if necessary. */
10666 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10667 /* Type INTEGER_CST can come from ordinary constant template args. */
10669 while (TREE_CODE (arg) == NOP_EXPR)
10670 arg = TREE_OPERAND (arg, 0);
10672 if (TREE_CODE (arg) != INTEGER_CST)
10674 return !tree_int_cst_equal (parm, arg);
10679 if (TREE_CODE (arg) != TREE_VEC)
10681 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10683 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10684 if (unify (tparms, targs,
10685 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10693 if (TREE_CODE (arg) != TREE_CODE (parm))
10696 if (TYPE_PTRMEMFUNC_P (parm))
10698 if (!TYPE_PTRMEMFUNC_P (arg))
10701 return unify (tparms, targs,
10702 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10703 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10707 if (CLASSTYPE_TEMPLATE_INFO (parm))
10709 tree t = NULL_TREE;
10711 if (strict_in & UNIFY_ALLOW_DERIVED)
10713 /* First, we try to unify the PARM and ARG directly. */
10714 t = try_class_unification (tparms, targs,
10719 /* Fallback to the special case allowed in
10720 [temp.deduct.call]:
10722 If P is a class, and P has the form
10723 template-id, then A can be a derived class of
10724 the deduced A. Likewise, if P is a pointer to
10725 a class of the form template-id, A can be a
10726 pointer to a derived class pointed to by the
10728 t = get_template_base (tparms, targs, parm, arg);
10734 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10735 && (CLASSTYPE_TI_TEMPLATE (parm)
10736 == CLASSTYPE_TI_TEMPLATE (arg)))
10737 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10738 Then, we should unify `int' and `U'. */
10741 /* There's no chance of unification succeeding. */
10744 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10745 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10747 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10752 case FUNCTION_TYPE:
10753 if (TREE_CODE (arg) != TREE_CODE (parm))
10756 /* CV qualifications for methods can never be deduced, they must
10757 match exactly. We need to check them explicitly here,
10758 because type_unification_real treats them as any other
10759 cvqualified parameter. */
10760 if (TREE_CODE (parm) == METHOD_TYPE
10761 && (!check_cv_quals_for_unify
10763 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
10764 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
10767 if (unify (tparms, targs, TREE_TYPE (parm),
10768 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10770 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10771 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10775 /* Unify a pointer to member with a pointer to member function, which
10776 deduces the type of the member as a function type. */
10777 if (TYPE_PTRMEMFUNC_P (arg))
10781 cp_cv_quals cv_quals;
10783 /* Check top-level cv qualifiers */
10784 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10787 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10788 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10791 /* Determine the type of the function we are unifying against. */
10792 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10794 build_function_type (TREE_TYPE (method_type),
10795 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10797 /* Extract the cv-qualifiers of the member function from the
10798 implicit object parameter and place them on the function
10799 type to be restored later. */
10801 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10802 fntype = build_qualified_type (fntype, cv_quals);
10803 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10806 if (TREE_CODE (arg) != OFFSET_TYPE)
10808 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10809 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10811 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10815 if (DECL_TEMPLATE_PARM_P (parm))
10816 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10817 if (arg != integral_constant_value (parm))
10822 case TEMPLATE_DECL:
10823 /* Matched cases are handled by the ARG == PARM test above. */
10827 gcc_assert (EXPR_P (parm));
10829 /* We must be looking at an expression. This can happen with
10833 void foo(S<I>, S<I + 2>);
10835 This is a "nondeduced context":
10839 The nondeduced contexts are:
10841 --A type that is a template-id in which one or more of
10842 the template-arguments is an expression that references
10843 a template-parameter.
10845 In these cases, we assume deduction succeeded, but don't
10846 actually infer any unifications. */
10848 if (!uses_template_parms (parm)
10849 && !template_args_equal (parm, arg))
10856 /* Note that DECL can be defined in this translation unit, if
10860 mark_definable (tree decl)
10863 DECL_NOT_REALLY_EXTERN (decl) = 1;
10864 FOR_EACH_CLONE (clone, decl)
10865 DECL_NOT_REALLY_EXTERN (clone) = 1;
10868 /* Called if RESULT is explicitly instantiated, or is a member of an
10869 explicitly instantiated class. */
10872 mark_decl_instantiated (tree result, int extern_p)
10874 SET_DECL_EXPLICIT_INSTANTIATION (result);
10876 /* If this entity has already been written out, it's too late to
10877 make any modifications. */
10878 if (TREE_ASM_WRITTEN (result))
10881 if (TREE_CODE (result) != FUNCTION_DECL)
10882 /* The TREE_PUBLIC flag for function declarations will have been
10883 set correctly by tsubst. */
10884 TREE_PUBLIC (result) = 1;
10886 /* This might have been set by an earlier implicit instantiation. */
10887 DECL_COMDAT (result) = 0;
10890 DECL_NOT_REALLY_EXTERN (result) = 0;
10893 mark_definable (result);
10894 /* Always make artificials weak. */
10895 if (DECL_ARTIFICIAL (result) && flag_weak)
10896 comdat_linkage (result);
10897 /* For WIN32 we also want to put explicit instantiations in
10898 linkonce sections. */
10899 else if (TREE_PUBLIC (result))
10900 maybe_make_one_only (result);
10903 /* If EXTERN_P, then this function will not be emitted -- unless
10904 followed by an explicit instantiation, at which point its linkage
10905 will be adjusted. If !EXTERN_P, then this function will be
10906 emitted here. In neither circumstance do we want
10907 import_export_decl to adjust the linkage. */
10908 DECL_INTERFACE_KNOWN (result) = 1;
10911 /* Given two function templates PAT1 and PAT2, return:
10913 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10914 -1 if PAT2 is more specialized than PAT1.
10915 0 if neither is more specialized.
10917 LEN indicates the number of parameters we should consider
10918 (defaulted parameters should not be considered).
10920 The 1998 std underspecified function template partial ordering, and
10921 DR214 addresses the issue. We take pairs of arguments, one from
10922 each of the templates, and deduce them against each other. One of
10923 the templates will be more specialized if all the *other*
10924 template's arguments deduce against its arguments and at least one
10925 of its arguments *does* *not* deduce against the other template's
10926 corresponding argument. Deduction is done as for class templates.
10927 The arguments used in deduction have reference and top level cv
10928 qualifiers removed. Iff both arguments were originally reference
10929 types *and* deduction succeeds in both directions, the template
10930 with the more cv-qualified argument wins for that pairing (if
10931 neither is more cv-qualified, they both are equal). Unlike regular
10932 deduction, after all the arguments have been deduced in this way,
10933 we do *not* verify the deduced template argument values can be
10934 substituted into non-deduced contexts, nor do we have to verify
10935 that all template arguments have been deduced. */
10938 more_specialized_fn (tree pat1, tree pat2, int len)
10940 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10941 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10942 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10943 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10944 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10945 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10946 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10947 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10951 /* Remove the this parameter from non-static member functions. If
10952 one is a non-static member function and the other is not a static
10953 member function, remove the first parameter from that function
10954 also. This situation occurs for operator functions where we
10955 locate both a member function (with this pointer) and non-member
10956 operator (with explicit first operand). */
10957 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10959 len--; /* LEN is the number of significant arguments for DECL1 */
10960 args1 = TREE_CHAIN (args1);
10961 if (!DECL_STATIC_FUNCTION_P (decl2))
10962 args2 = TREE_CHAIN (args2);
10964 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10966 args2 = TREE_CHAIN (args2);
10967 if (!DECL_STATIC_FUNCTION_P (decl1))
10970 args1 = TREE_CHAIN (args1);
10974 /* If only one is a conversion operator, they are unordered. */
10975 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10978 /* Consider the return type for a conversion function */
10979 if (DECL_CONV_FN_P (decl1))
10981 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10982 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10986 processing_template_decl++;
10990 tree arg1 = TREE_VALUE (args1);
10991 tree arg2 = TREE_VALUE (args2);
10992 int deduce1, deduce2;
10996 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10998 arg1 = TREE_TYPE (arg1);
10999 quals1 = cp_type_quals (arg1);
11002 if (TREE_CODE (arg2) == REFERENCE_TYPE)
11004 arg2 = TREE_TYPE (arg2);
11005 quals2 = cp_type_quals (arg2);
11008 if ((quals1 < 0) != (quals2 < 0))
11010 /* Only of the args is a reference, see if we should apply
11011 array/function pointer decay to it. This is not part of
11012 DR214, but is, IMHO, consistent with the deduction rules
11013 for the function call itself, and with our earlier
11014 implementation of the underspecified partial ordering
11015 rules. (nathan). */
11018 switch (TREE_CODE (arg1))
11021 arg1 = TREE_TYPE (arg1);
11023 case FUNCTION_TYPE:
11024 arg1 = build_pointer_type (arg1);
11033 switch (TREE_CODE (arg2))
11036 arg2 = TREE_TYPE (arg2);
11038 case FUNCTION_TYPE:
11039 arg2 = build_pointer_type (arg2);
11048 arg1 = TYPE_MAIN_VARIANT (arg1);
11049 arg2 = TYPE_MAIN_VARIANT (arg2);
11051 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
11052 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
11058 if (better1 < 0 && better2 < 0)
11059 /* We've failed to deduce something in either direction.
11060 These must be unordered. */
11063 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
11065 /* Deduces in both directions, see if quals can
11066 disambiguate. Pretend the worse one failed to deduce. */
11067 if ((quals1 & quals2) == quals2)
11069 if ((quals1 & quals2) == quals1)
11072 if (deduce1 && !deduce2 && !better2)
11074 if (deduce2 && !deduce1 && !better1)
11077 args1 = TREE_CHAIN (args1);
11078 args2 = TREE_CHAIN (args2);
11081 processing_template_decl--;
11083 return (better1 > 0) - (better2 > 0);
11086 /* Determine which of two partial specializations is more specialized.
11088 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
11089 to the first partial specialization. The TREE_VALUE is the
11090 innermost set of template parameters for the partial
11091 specialization. PAT2 is similar, but for the second template.
11093 Return 1 if the first partial specialization is more specialized;
11094 -1 if the second is more specialized; 0 if neither is more
11097 See [temp.class.order] for information about determining which of
11098 two templates is more specialized. */
11101 more_specialized_class (tree pat1, tree pat2)
11107 tmpl1 = TREE_TYPE (pat1);
11108 tmpl2 = TREE_TYPE (pat2);
11110 /* Just like what happens for functions, if we are ordering between
11111 different class template specializations, we may encounter dependent
11112 types in the arguments, and we need our dependency check functions
11113 to behave correctly. */
11114 ++processing_template_decl;
11115 targs = get_class_bindings (TREE_VALUE (pat1),
11116 CLASSTYPE_TI_ARGS (tmpl1),
11117 CLASSTYPE_TI_ARGS (tmpl2));
11121 targs = get_class_bindings (TREE_VALUE (pat2),
11122 CLASSTYPE_TI_ARGS (tmpl2),
11123 CLASSTYPE_TI_ARGS (tmpl1));
11126 --processing_template_decl;
11131 /* Return the template arguments that will produce the function signature
11132 DECL from the function template FN, with the explicit template
11133 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
11134 also match. Return NULL_TREE if no satisfactory arguments could be
11138 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
11140 int ntparms = DECL_NTPARMS (fn);
11141 tree targs = make_tree_vec (ntparms);
11143 tree decl_arg_types;
11145 /* Substitute the explicit template arguments into the type of DECL.
11146 The call to fn_type_unification will handle substitution into the
11148 decl_type = TREE_TYPE (decl);
11149 if (explicit_args && uses_template_parms (decl_type))
11152 tree converted_args;
11154 if (DECL_TEMPLATE_INFO (decl))
11155 tmpl = DECL_TI_TEMPLATE (decl);
11157 /* We can get here for some invalid specializations. */
11161 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
11162 explicit_args, NULL_TREE,
11164 /*require_all_args=*/false,
11165 /*use_default_args=*/false);
11166 if (converted_args == error_mark_node)
11169 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
11170 if (decl_type == error_mark_node)
11174 decl_arg_types = TYPE_ARG_TYPES (decl_type);
11175 /* Never do unification on the 'this' parameter. */
11176 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
11177 decl_arg_types = TREE_CHAIN (decl_arg_types);
11179 if (fn_type_unification (fn, explicit_args, targs,
11181 (check_rettype || DECL_CONV_FN_P (fn)
11182 ? TREE_TYPE (decl_type) : NULL_TREE),
11183 DEDUCE_EXACT, LOOKUP_NORMAL))
11189 /* Return the innermost template arguments that, when applied to a
11190 template specialization whose innermost template parameters are
11191 TPARMS, and whose specialization arguments are PARMS, yield the
11194 For example, suppose we have:
11196 template <class T, class U> struct S {};
11197 template <class T> struct S<T*, int> {};
11199 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
11200 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
11201 int}. The resulting vector will be {double}, indicating that `T'
11202 is bound to `double'. */
11205 get_class_bindings (tree tparms, tree spec_args, tree args)
11207 int i, ntparms = TREE_VEC_LENGTH (tparms);
11209 tree innermost_deduced_args;
11211 innermost_deduced_args = make_tree_vec (ntparms);
11212 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
11214 deduced_args = copy_node (args);
11215 SET_TMPL_ARGS_LEVEL (deduced_args,
11216 TMPL_ARGS_DEPTH (deduced_args),
11217 innermost_deduced_args);
11220 deduced_args = innermost_deduced_args;
11222 if (unify (tparms, deduced_args,
11223 INNERMOST_TEMPLATE_ARGS (spec_args),
11224 INNERMOST_TEMPLATE_ARGS (args),
11228 for (i = 0; i < ntparms; ++i)
11229 if (! TREE_VEC_ELT (innermost_deduced_args, i))
11232 /* Verify that nondeduced template arguments agree with the type
11233 obtained from argument deduction.
11237 struct A { typedef int X; };
11238 template <class T, class U> struct C {};
11239 template <class T> struct C<T, typename T::X> {};
11241 Then with the instantiation `C<A, int>', we can deduce that
11242 `T' is `A' but unify () does not check whether `typename T::X'
11244 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
11245 if (spec_args == error_mark_node
11246 /* We only need to check the innermost arguments; the other
11247 arguments will always agree. */
11248 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
11249 INNERMOST_TEMPLATE_ARGS (args)))
11252 return deduced_args;
11255 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
11256 Return the TREE_LIST node with the most specialized template, if
11257 any. If there is no most specialized template, the error_mark_node
11260 Note that this function does not look at, or modify, the
11261 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
11262 returned is one of the elements of INSTANTIATIONS, callers may
11263 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
11264 and retrieve it from the value returned. */
11267 most_specialized_instantiation (tree templates)
11271 ++processing_template_decl;
11274 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
11278 if (get_bindings (TREE_VALUE (champ),
11279 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
11280 NULL_TREE, /*check_ret=*/false))
11283 if (get_bindings (TREE_VALUE (fn),
11284 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
11285 NULL_TREE, /*check_ret=*/false))
11292 /* Equally specialized, move to next function. If there
11293 is no next function, nothing's most specialized. */
11294 fn = TREE_CHAIN (fn);
11302 /* Now verify that champ is better than everything earlier in the
11303 instantiation list. */
11304 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
11305 if (get_bindings (TREE_VALUE (champ),
11306 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
11307 NULL_TREE, /*check_ret=*/false)
11308 || !get_bindings (TREE_VALUE (fn),
11309 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
11310 NULL_TREE, /*check_ret=*/false))
11316 processing_template_decl--;
11319 return error_mark_node;
11324 /* If DECL is a specialization of some template, return the most
11325 general such template. Otherwise, returns NULL_TREE.
11327 For example, given:
11329 template <class T> struct S { template <class U> void f(U); };
11331 if TMPL is `template <class U> void S<int>::f(U)' this will return
11332 the full template. This function will not trace past partial
11333 specializations, however. For example, given in addition:
11335 template <class T> struct S<T*> { template <class U> void f(U); };
11337 if TMPL is `template <class U> void S<int*>::f(U)' this will return
11338 `template <class T> template <class U> S<T*>::f(U)'. */
11341 most_general_template (tree decl)
11343 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
11344 an immediate specialization. */
11345 if (TREE_CODE (decl) == FUNCTION_DECL)
11347 if (DECL_TEMPLATE_INFO (decl)) {
11348 decl = DECL_TI_TEMPLATE (decl);
11350 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
11351 template friend. */
11352 if (TREE_CODE (decl) != TEMPLATE_DECL)
11358 /* Look for more and more general templates. */
11359 while (DECL_TEMPLATE_INFO (decl))
11361 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
11362 (See cp-tree.h for details.) */
11363 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
11366 if (CLASS_TYPE_P (TREE_TYPE (decl))
11367 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
11370 /* Stop if we run into an explicitly specialized class template. */
11371 if (!DECL_NAMESPACE_SCOPE_P (decl)
11372 && DECL_CONTEXT (decl)
11373 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
11376 decl = DECL_TI_TEMPLATE (decl);
11382 /* Return the most specialized of the class template partial
11383 specializations of TMPL which can produce TYPE, a specialization of
11384 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
11385 a _TYPE node corresponding to the partial specialization, while the
11386 TREE_PURPOSE is the set of template arguments that must be
11387 substituted into the TREE_TYPE in order to generate TYPE.
11389 If the choice of partial specialization is ambiguous, a diagnostic
11390 is issued, and the error_mark_node is returned. If there are no
11391 partial specializations of TMPL matching TYPE, then NULL_TREE is
11395 most_specialized_class (tree type, tree tmpl)
11397 tree list = NULL_TREE;
11404 tmpl = most_general_template (tmpl);
11405 args = CLASSTYPE_TI_ARGS (type);
11406 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
11408 tree partial_spec_args;
11411 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
11412 spec_args = get_class_bindings (TREE_VALUE (t),
11417 list = tree_cons (spec_args, TREE_VALUE (t), list);
11418 TREE_TYPE (list) = TREE_TYPE (t);
11425 ambiguous_p = false;
11428 t = TREE_CHAIN (t);
11429 for (; t; t = TREE_CHAIN (t))
11431 fate = more_specialized_class (champ, t);
11438 t = TREE_CHAIN (t);
11441 ambiguous_p = true;
11450 for (t = list; t && t != champ; t = TREE_CHAIN (t))
11452 fate = more_specialized_class (champ, t);
11455 ambiguous_p = true;
11462 const char *str = "candidates are:";
11463 error ("ambiguous class template instantiation for %q#T", type);
11464 for (t = list; t; t = TREE_CHAIN (t))
11466 error ("%s %+#T", str, TREE_TYPE (t));
11469 return error_mark_node;
11475 /* Explicitly instantiate DECL. */
11478 do_decl_instantiation (tree decl, tree storage)
11480 tree result = NULL_TREE;
11483 if (!decl || decl == error_mark_node)
11484 /* An error occurred, for which grokdeclarator has already issued
11485 an appropriate message. */
11487 else if (! DECL_LANG_SPECIFIC (decl))
11489 error ("explicit instantiation of non-template %q#D", decl);
11492 else if (TREE_CODE (decl) == VAR_DECL)
11494 /* There is an asymmetry here in the way VAR_DECLs and
11495 FUNCTION_DECLs are handled by grokdeclarator. In the case of
11496 the latter, the DECL we get back will be marked as a
11497 template instantiation, and the appropriate
11498 DECL_TEMPLATE_INFO will be set up. This does not happen for
11499 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
11500 should handle VAR_DECLs as it currently handles
11502 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
11503 if (!result || TREE_CODE (result) != VAR_DECL)
11505 error ("no matching template for %qD found", decl);
11509 else if (TREE_CODE (decl) != FUNCTION_DECL)
11511 error ("explicit instantiation of %q#D", decl);
11517 /* Check for various error cases. Note that if the explicit
11518 instantiation is valid the RESULT will currently be marked as an
11519 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
11520 until we get here. */
11522 if (DECL_TEMPLATE_SPECIALIZATION (result))
11524 /* DR 259 [temp.spec].
11526 Both an explicit instantiation and a declaration of an explicit
11527 specialization shall not appear in a program unless the explicit
11528 instantiation follows a declaration of the explicit specialization.
11530 For a given set of template parameters, if an explicit
11531 instantiation of a template appears after a declaration of an
11532 explicit specialization for that template, the explicit
11533 instantiation has no effect. */
11536 else if (DECL_EXPLICIT_INSTANTIATION (result))
11540 No program shall explicitly instantiate any template more
11543 We check DECL_NOT_REALLY_EXTERN so as not to complain when
11544 the first instantiation was `extern' and the second is not,
11545 and EXTERN_P for the opposite case. */
11546 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
11547 pedwarn ("duplicate explicit instantiation of %q#D", result);
11548 /* If an "extern" explicit instantiation follows an ordinary
11549 explicit instantiation, the template is instantiated. */
11553 else if (!DECL_IMPLICIT_INSTANTIATION (result))
11555 error ("no matching template for %qD found", result);
11558 else if (!DECL_TEMPLATE_INFO (result))
11560 pedwarn ("explicit instantiation of non-template %q#D", result);
11564 if (storage == NULL_TREE)
11566 else if (storage == ridpointers[(int) RID_EXTERN])
11568 if (pedantic && !in_system_header)
11569 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11574 error ("storage class %qD applied to template instantiation", storage);
11576 check_explicit_instantiation_namespace (result);
11577 mark_decl_instantiated (result, extern_p);
11579 instantiate_decl (result, /*defer_ok=*/1,
11580 /*expl_inst_class_mem_p=*/false);
11584 mark_class_instantiated (tree t, int extern_p)
11586 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11587 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11588 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11589 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11592 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11593 rest_of_type_compilation (t, 1);
11597 /* Called from do_type_instantiation through binding_table_foreach to
11598 do recursive instantiation for the type bound in ENTRY. */
11600 bt_instantiate_type_proc (binding_entry entry, void *data)
11602 tree storage = *(tree *) data;
11604 if (IS_AGGR_TYPE (entry->type)
11605 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11606 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11609 /* Called from do_type_instantiation to instantiate a member
11610 (a member function or a static member variable) of an
11611 explicitly instantiated class template. */
11613 instantiate_class_member (tree decl, int extern_p)
11615 mark_decl_instantiated (decl, extern_p);
11617 instantiate_decl (decl, /*defer_ok=*/1,
11618 /*expl_inst_class_mem_p=*/true);
11621 /* Perform an explicit instantiation of template class T. STORAGE, if
11622 non-null, is the RID for extern, inline or static. COMPLAIN is
11623 nonzero if this is called from the parser, zero if called recursively,
11624 since the standard is unclear (as detailed below). */
11627 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11632 int previous_instantiation_extern_p = 0;
11634 if (TREE_CODE (t) == TYPE_DECL)
11637 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11639 error ("explicit instantiation of non-template type %qT", t);
11645 if (!COMPLETE_TYPE_P (t))
11647 if (complain & tf_error)
11648 error ("explicit instantiation of %q#T before definition of template",
11653 if (storage != NULL_TREE)
11655 if (pedantic && !in_system_header)
11656 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11659 if (storage == ridpointers[(int) RID_INLINE])
11661 else if (storage == ridpointers[(int) RID_EXTERN])
11663 else if (storage == ridpointers[(int) RID_STATIC])
11667 error ("storage class %qD applied to template instantiation",
11673 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11675 /* DR 259 [temp.spec].
11677 Both an explicit instantiation and a declaration of an explicit
11678 specialization shall not appear in a program unless the explicit
11679 instantiation follows a declaration of the explicit specialization.
11681 For a given set of template parameters, if an explicit
11682 instantiation of a template appears after a declaration of an
11683 explicit specialization for that template, the explicit
11684 instantiation has no effect. */
11687 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11691 No program shall explicitly instantiate any template more
11694 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11695 instantiation was `extern'. If EXTERN_P then the second is.
11696 These cases are OK. */
11697 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11699 if (!previous_instantiation_extern_p && !extern_p
11700 && (complain & tf_error))
11701 pedwarn ("duplicate explicit instantiation of %q#T", t);
11703 /* If we've already instantiated the template, just return now. */
11704 if (!CLASSTYPE_INTERFACE_ONLY (t))
11708 check_explicit_instantiation_namespace (TYPE_NAME (t));
11709 mark_class_instantiated (t, extern_p);
11717 /* In contrast to implicit instantiation, where only the
11718 declarations, and not the definitions, of members are
11719 instantiated, we have here:
11723 The explicit instantiation of a class template specialization
11724 implies the instantiation of all of its members not
11725 previously explicitly specialized in the translation unit
11726 containing the explicit instantiation.
11728 Of course, we can't instantiate member template classes, since
11729 we don't have any arguments for them. Note that the standard
11730 is unclear on whether the instantiation of the members are
11731 *explicit* instantiations or not. However, the most natural
11732 interpretation is that it should be an explicit instantiation. */
11735 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11736 if (TREE_CODE (tmp) == FUNCTION_DECL
11737 && DECL_TEMPLATE_INSTANTIATION (tmp))
11738 instantiate_class_member (tmp, extern_p);
11740 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11741 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11742 instantiate_class_member (tmp, extern_p);
11744 if (CLASSTYPE_NESTED_UTDS (t))
11745 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11746 bt_instantiate_type_proc, &storage);
11750 /* Given a function DECL, which is a specialization of TMPL, modify
11751 DECL to be a re-instantiation of TMPL with the same template
11752 arguments. TMPL should be the template into which tsubst'ing
11753 should occur for DECL, not the most general template.
11755 One reason for doing this is a scenario like this:
11758 void f(const T&, int i);
11760 void g() { f(3, 7); }
11763 void f(const T& t, const int i) { }
11765 Note that when the template is first instantiated, with
11766 instantiate_template, the resulting DECL will have no name for the
11767 first parameter, and the wrong type for the second. So, when we go
11768 to instantiate the DECL, we regenerate it. */
11771 regenerate_decl_from_template (tree decl, tree tmpl)
11773 /* The arguments used to instantiate DECL, from the most general
11778 args = DECL_TI_ARGS (decl);
11779 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11781 /* Make sure that we can see identifiers, and compute access
11783 push_access_scope (decl);
11785 if (TREE_CODE (decl) == FUNCTION_DECL)
11793 args_depth = TMPL_ARGS_DEPTH (args);
11794 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11795 if (args_depth > parms_depth)
11796 args = get_innermost_template_args (args, parms_depth);
11798 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11799 args, tf_error, NULL_TREE);
11801 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11804 /* Merge parameter declarations. */
11805 decl_parm = skip_artificial_parms_for (decl,
11806 DECL_ARGUMENTS (decl));
11808 = skip_artificial_parms_for (code_pattern,
11809 DECL_ARGUMENTS (code_pattern));
11815 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11816 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11817 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11819 parm_type = type_decays_to (parm_type);
11820 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11821 TREE_TYPE (decl_parm) = parm_type;
11822 attributes = DECL_ATTRIBUTES (pattern_parm);
11823 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11825 DECL_ATTRIBUTES (decl_parm) = attributes;
11826 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11828 decl_parm = TREE_CHAIN (decl_parm);
11829 pattern_parm = TREE_CHAIN (pattern_parm);
11832 /* Merge additional specifiers from the CODE_PATTERN. */
11833 if (DECL_DECLARED_INLINE_P (code_pattern)
11834 && !DECL_DECLARED_INLINE_P (decl))
11835 DECL_DECLARED_INLINE_P (decl) = 1;
11836 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11837 DECL_INLINE (decl) = 1;
11839 else if (TREE_CODE (decl) == VAR_DECL)
11840 DECL_INITIAL (decl) =
11841 tsubst_expr (DECL_INITIAL (code_pattern), args,
11842 tf_error, DECL_TI_TEMPLATE (decl),
11843 /*integral_constant_expression_p=*/false);
11845 gcc_unreachable ();
11847 pop_access_scope (decl);
11850 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11851 substituted to get DECL. */
11854 template_for_substitution (tree decl)
11856 tree tmpl = DECL_TI_TEMPLATE (decl);
11858 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11859 for the instantiation. This is not always the most general
11860 template. Consider, for example:
11863 struct S { template <class U> void f();
11864 template <> void f<int>(); };
11866 and an instantiation of S<double>::f<int>. We want TD to be the
11867 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11868 while (/* An instantiation cannot have a definition, so we need a
11869 more general template. */
11870 DECL_TEMPLATE_INSTANTIATION (tmpl)
11871 /* We must also deal with friend templates. Given:
11873 template <class T> struct S {
11874 template <class U> friend void f() {};
11877 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11878 so far as the language is concerned, but that's still
11879 where we get the pattern for the instantiation from. On
11880 other hand, if the definition comes outside the class, say:
11882 template <class T> struct S {
11883 template <class U> friend void f();
11885 template <class U> friend void f() {}
11887 we don't need to look any further. That's what the check for
11888 DECL_INITIAL is for. */
11889 || (TREE_CODE (decl) == FUNCTION_DECL
11890 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11891 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11893 /* The present template, TD, should not be a definition. If it
11894 were a definition, we should be using it! Note that we
11895 cannot restructure the loop to just keep going until we find
11896 a template with a definition, since that might go too far if
11897 a specialization was declared, but not defined. */
11898 gcc_assert (TREE_CODE (decl) != VAR_DECL
11899 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11901 /* Fetch the more general template. */
11902 tmpl = DECL_TI_TEMPLATE (tmpl);
11908 /* Produce the definition of D, a _DECL generated from a template. If
11909 DEFER_OK is nonzero, then we don't have to actually do the
11910 instantiation now; we just have to do it sometime. Normally it is
11911 an error if this is an explicit instantiation but D is undefined.
11912 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
11913 explicitly instantiated class template. */
11916 instantiate_decl (tree d, int defer_ok,
11917 bool expl_inst_class_mem_p)
11919 tree tmpl = DECL_TI_TEMPLATE (d);
11926 bool pattern_defined;
11928 location_t saved_loc = input_location;
11931 /* This function should only be used to instantiate templates for
11932 functions and static member variables. */
11933 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11934 || TREE_CODE (d) == VAR_DECL);
11936 /* Variables are never deferred; if instantiation is required, they
11937 are instantiated right away. That allows for better code in the
11938 case that an expression refers to the value of the variable --
11939 if the variable has a constant value the referring expression can
11940 take advantage of that fact. */
11941 if (TREE_CODE (d) == VAR_DECL)
11944 /* Don't instantiate cloned functions. Instead, instantiate the
11945 functions they cloned. */
11946 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11947 d = DECL_CLONED_FUNCTION (d);
11949 if (DECL_TEMPLATE_INSTANTIATED (d))
11950 /* D has already been instantiated. It might seem reasonable to
11951 check whether or not D is an explicit instantiation, and, if so,
11952 stop here. But when an explicit instantiation is deferred
11953 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11954 is set, even though we still need to do the instantiation. */
11957 /* If we already have a specialization of this declaration, then
11958 there's no reason to instantiate it. Note that
11959 retrieve_specialization gives us both instantiations and
11960 specializations, so we must explicitly check
11961 DECL_TEMPLATE_SPECIALIZATION. */
11962 gen_tmpl = most_general_template (tmpl);
11963 gen_args = DECL_TI_ARGS (d);
11964 spec = retrieve_specialization (gen_tmpl, gen_args,
11965 /*class_specializations_p=*/false);
11966 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11969 /* This needs to happen before any tsubsting. */
11970 if (! push_tinst_level (d))
11973 timevar_push (TV_PARSE);
11975 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11976 for the instantiation. */
11977 td = template_for_substitution (d);
11978 code_pattern = DECL_TEMPLATE_RESULT (td);
11980 /* We should never be trying to instantiate a member of a class
11981 template or partial specialization. */
11982 gcc_assert (d != code_pattern);
11984 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11985 || DECL_TEMPLATE_SPECIALIZATION (td))
11986 /* In the case of a friend template whose definition is provided
11987 outside the class, we may have too many arguments. Drop the
11988 ones we don't need. The same is true for specializations. */
11989 args = get_innermost_template_args
11990 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11994 if (TREE_CODE (d) == FUNCTION_DECL)
11995 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11997 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11999 /* We may be in the middle of deferred access check. Disable it now. */
12000 push_deferring_access_checks (dk_no_deferred);
12002 /* Unless an explicit instantiation directive has already determined
12003 the linkage of D, remember that a definition is available for
12005 if (pattern_defined
12006 && !DECL_INTERFACE_KNOWN (d)
12007 && !DECL_NOT_REALLY_EXTERN (d))
12008 mark_definable (d);
12010 input_location = DECL_SOURCE_LOCATION (d);
12012 /* If D is a member of an explicitly instantiated class template,
12013 and no definition is available, treat it like an implicit
12015 if (!pattern_defined && expl_inst_class_mem_p
12016 && DECL_EXPLICIT_INSTANTIATION (d))
12018 DECL_NOT_REALLY_EXTERN (d) = 0;
12019 DECL_INTERFACE_KNOWN (d) = 0;
12020 SET_DECL_IMPLICIT_INSTANTIATION (d);
12025 /* Recheck the substitutions to obtain any warning messages
12026 about ignoring cv qualifiers. */
12027 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
12028 tree type = TREE_TYPE (gen);
12030 /* Make sure that we can see identifiers, and compute access
12031 correctly. D is already the target FUNCTION_DECL with the
12033 push_access_scope (d);
12035 if (TREE_CODE (gen) == FUNCTION_DECL)
12037 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
12038 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
12039 tf_warning_or_error, d);
12040 /* Don't simply tsubst the function type, as that will give
12041 duplicate warnings about poor parameter qualifications.
12042 The function arguments are the same as the decl_arguments
12043 without the top level cv qualifiers. */
12044 type = TREE_TYPE (type);
12046 tsubst (type, gen_args, tf_warning_or_error, d);
12048 pop_access_scope (d);
12051 /* Check to see whether we know that this template will be
12052 instantiated in some other file, as with "extern template"
12054 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
12055 /* In general, we do not instantiate such templates... */
12057 /* ... but we instantiate inline functions so that we can inline
12059 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
12060 /* ... we instantiate static data members whose values are
12061 needed in integral constant expressions. */
12062 && ! (TREE_CODE (d) == VAR_DECL
12063 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
12065 /* Defer all other templates, unless we have been explicitly
12066 forbidden from doing so. */
12067 if (/* If there is no definition, we cannot instantiate the
12070 /* If it's OK to postpone instantiation, do so. */
12072 /* If this is a static data member that will be defined
12073 elsewhere, we don't want to instantiate the entire data
12074 member, but we do want to instantiate the initializer so that
12075 we can substitute that elsewhere. */
12076 || (external_p && TREE_CODE (d) == VAR_DECL))
12078 /* The definition of the static data member is now required so
12079 we must substitute the initializer. */
12080 if (TREE_CODE (d) == VAR_DECL
12081 && !DECL_INITIAL (d)
12082 && DECL_INITIAL (code_pattern))
12087 ns = decl_namespace_context (d);
12088 push_nested_namespace (ns);
12089 push_nested_class (DECL_CONTEXT (d));
12090 init = tsubst_expr (DECL_INITIAL (code_pattern),
12092 tf_warning_or_error, NULL_TREE,
12093 /*integral_constant_expression_p=*/false);
12094 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
12095 /*asmspec_tree=*/NULL_TREE,
12096 LOOKUP_ONLYCONVERTING);
12097 pop_nested_class ();
12098 pop_nested_namespace (ns);
12101 /* We restore the source position here because it's used by
12102 add_pending_template. */
12103 input_location = saved_loc;
12105 if (at_eof && !pattern_defined
12106 && DECL_EXPLICIT_INSTANTIATION (d))
12109 The definition of a non-exported function template, a
12110 non-exported member function template, or a non-exported
12111 member function or static data member of a class template
12112 shall be present in every translation unit in which it is
12113 explicitly instantiated. */
12115 ("explicit instantiation of %qD but no definition available", d);
12117 /* ??? Historically, we have instantiated inline functions, even
12118 when marked as "extern template". */
12119 if (!(external_p && TREE_CODE (d) == VAR_DECL))
12120 add_pending_template (d);
12123 /* Tell the repository that D is available in this translation unit
12124 -- and see if it is supposed to be instantiated here. */
12125 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
12127 /* In a PCH file, despite the fact that the repository hasn't
12128 requested instantiation in the PCH it is still possible that
12129 an instantiation will be required in a file that includes the
12132 add_pending_template (d);
12133 /* Instantiate inline functions so that the inliner can do its
12134 job, even though we'll not be emitting a copy of this
12136 if (!(TREE_CODE (d) == FUNCTION_DECL
12137 && flag_inline_trees
12138 && DECL_DECLARED_INLINE_P (d)))
12142 need_push = !cfun || !global_bindings_p ();
12144 push_to_top_level ();
12146 /* Mark D as instantiated so that recursive calls to
12147 instantiate_decl do not try to instantiate it again. */
12148 DECL_TEMPLATE_INSTANTIATED (d) = 1;
12150 /* Regenerate the declaration in case the template has been modified
12151 by a subsequent redeclaration. */
12152 regenerate_decl_from_template (d, td);
12154 /* We already set the file and line above. Reset them now in case
12155 they changed as a result of calling regenerate_decl_from_template. */
12156 input_location = DECL_SOURCE_LOCATION (d);
12158 if (TREE_CODE (d) == VAR_DECL)
12162 /* Clear out DECL_RTL; whatever was there before may not be right
12163 since we've reset the type of the declaration. */
12164 SET_DECL_RTL (d, NULL_RTX);
12165 DECL_IN_AGGR_P (d) = 0;
12167 /* The initializer is placed in DECL_INITIAL by
12168 regenerate_decl_from_template. Pull it out so that
12169 finish_decl can process it. */
12170 init = DECL_INITIAL (d);
12171 DECL_INITIAL (d) = NULL_TREE;
12172 DECL_INITIALIZED_P (d) = 0;
12174 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
12175 initializer. That function will defer actual emission until
12176 we have a chance to determine linkage. */
12177 DECL_EXTERNAL (d) = 0;
12179 /* Enter the scope of D so that access-checking works correctly. */
12180 push_nested_class (DECL_CONTEXT (d));
12181 finish_decl (d, init, NULL_TREE);
12182 pop_nested_class ();
12184 else if (TREE_CODE (d) == FUNCTION_DECL)
12186 htab_t saved_local_specializations;
12191 /* Save away the current list, in case we are instantiating one
12192 template from within the body of another. */
12193 saved_local_specializations = local_specializations;
12195 /* Set up the list of local specializations. */
12196 local_specializations = htab_create (37,
12197 hash_local_specialization,
12198 eq_local_specializations,
12201 /* Set up context. */
12202 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
12204 /* Create substitution entries for the parameters. */
12205 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
12206 tmpl_parm = DECL_ARGUMENTS (subst_decl);
12207 spec_parm = DECL_ARGUMENTS (d);
12208 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
12210 register_local_specialization (spec_parm, tmpl_parm);
12211 spec_parm = skip_artificial_parms_for (d, spec_parm);
12212 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
12216 register_local_specialization (spec_parm, tmpl_parm);
12217 tmpl_parm = TREE_CHAIN (tmpl_parm);
12218 spec_parm = TREE_CHAIN (spec_parm);
12220 gcc_assert (!spec_parm);
12222 /* Substitute into the body of the function. */
12223 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
12224 tf_warning_or_error, tmpl,
12225 /*integral_constant_expression_p=*/false);
12227 /* We don't need the local specializations any more. */
12228 htab_delete (local_specializations);
12229 local_specializations = saved_local_specializations;
12231 /* Finish the function. */
12232 d = finish_function (0);
12233 expand_or_defer_fn (d);
12236 /* We're not deferring instantiation any more. */
12237 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
12240 pop_from_top_level ();
12243 input_location = saved_loc;
12244 pop_deferring_access_checks ();
12245 pop_tinst_level ();
12247 timevar_pop (TV_PARSE);
12252 /* Run through the list of templates that we wish we could
12253 instantiate, and instantiate any we can. RETRIES is the
12254 number of times we retry pending template instantiation. */
12257 instantiate_pending_templates (int retries)
12260 tree last = NULL_TREE;
12262 location_t saved_loc = input_location;
12263 int saved_in_system_header = in_system_header;
12265 /* Instantiating templates may trigger vtable generation. This in turn
12266 may require further template instantiations. We place a limit here
12267 to avoid infinite loop. */
12268 if (pending_templates && retries >= max_tinst_depth)
12270 tree decl = TREE_VALUE (pending_templates);
12272 error ("template instantiation depth exceeds maximum of %d"
12273 " instantiating %q+D, possibly from virtual table generation"
12274 " (use -ftemplate-depth-NN to increase the maximum)",
12275 max_tinst_depth, decl);
12276 if (TREE_CODE (decl) == FUNCTION_DECL)
12277 /* Pretend that we defined it. */
12278 DECL_INITIAL (decl) = error_mark_node;
12286 t = &pending_templates;
12289 tree instantiation = TREE_VALUE (*t);
12291 reopen_tinst_level (TREE_PURPOSE (*t));
12293 if (TYPE_P (instantiation))
12297 if (!COMPLETE_TYPE_P (instantiation))
12299 instantiate_class_template (instantiation);
12300 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
12301 for (fn = TYPE_METHODS (instantiation);
12303 fn = TREE_CHAIN (fn))
12304 if (! DECL_ARTIFICIAL (fn))
12305 instantiate_decl (fn,
12307 /*expl_inst_class_mem_p=*/false);
12308 if (COMPLETE_TYPE_P (instantiation))
12312 if (COMPLETE_TYPE_P (instantiation))
12313 /* If INSTANTIATION has been instantiated, then we don't
12314 need to consider it again in the future. */
12315 *t = TREE_CHAIN (*t);
12319 t = &TREE_CHAIN (*t);
12324 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
12325 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
12328 = instantiate_decl (instantiation,
12330 /*expl_inst_class_mem_p=*/false);
12331 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
12335 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
12336 || DECL_TEMPLATE_INSTANTIATED (instantiation))
12337 /* If INSTANTIATION has been instantiated, then we don't
12338 need to consider it again in the future. */
12339 *t = TREE_CHAIN (*t);
12343 t = &TREE_CHAIN (*t);
12347 current_tinst_level = NULL_TREE;
12349 last_pending_template = last;
12351 while (reconsider);
12353 input_location = saved_loc;
12354 in_system_header = saved_in_system_header;
12357 /* Substitute ARGVEC into T, which is a list of initializers for
12358 either base class or a non-static data member. The TREE_PURPOSEs
12359 are DECLs, and the TREE_VALUEs are the initializer values. Used by
12360 instantiate_decl. */
12363 tsubst_initializer_list (tree t, tree argvec)
12365 tree inits = NULL_TREE;
12367 for (; t; t = TREE_CHAIN (t))
12372 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_warning_or_error,
12374 decl = expand_member_init (decl);
12375 if (decl && !DECL_P (decl))
12376 in_base_initializer = 1;
12378 init = tsubst_expr (TREE_VALUE (t), argvec, tf_warning_or_error,
12380 /*integral_constant_expression_p=*/false);
12381 in_base_initializer = 0;
12385 init = build_tree_list (decl, init);
12386 TREE_CHAIN (init) = inits;
12393 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
12396 set_current_access_from_decl (tree decl)
12398 if (TREE_PRIVATE (decl))
12399 current_access_specifier = access_private_node;
12400 else if (TREE_PROTECTED (decl))
12401 current_access_specifier = access_protected_node;
12403 current_access_specifier = access_public_node;
12406 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
12407 is the instantiation (which should have been created with
12408 start_enum) and ARGS are the template arguments to use. */
12411 tsubst_enum (tree tag, tree newtag, tree args)
12415 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
12420 decl = TREE_VALUE (e);
12421 /* Note that in a template enum, the TREE_VALUE is the
12422 CONST_DECL, not the corresponding INTEGER_CST. */
12423 value = tsubst_expr (DECL_INITIAL (decl),
12424 args, tf_warning_or_error, NULL_TREE,
12425 /*integral_constant_expression_p=*/true);
12427 /* Give this enumeration constant the correct access. */
12428 set_current_access_from_decl (decl);
12430 /* Actually build the enumerator itself. */
12431 build_enumerator (DECL_NAME (decl), value, newtag);
12434 finish_enum (newtag);
12435 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
12436 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
12439 /* DECL is a FUNCTION_DECL that is a template specialization. Return
12440 its type -- but without substituting the innermost set of template
12441 arguments. So, innermost set of template parameters will appear in
12445 get_mostly_instantiated_function_type (tree decl)
12453 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
12454 targs = DECL_TI_ARGS (decl);
12455 tparms = DECL_TEMPLATE_PARMS (tmpl);
12456 parm_depth = TMPL_PARMS_DEPTH (tparms);
12458 /* There should be as many levels of arguments as there are levels
12460 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
12462 fn_type = TREE_TYPE (tmpl);
12464 if (parm_depth == 1)
12465 /* No substitution is necessary. */
12469 int i, save_access_control;
12472 /* Replace the innermost level of the TARGS with NULL_TREEs to
12473 let tsubst know not to substitute for those parameters. */
12474 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
12475 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
12476 SET_TMPL_ARGS_LEVEL (partial_args, i,
12477 TMPL_ARGS_LEVEL (targs, i));
12478 SET_TMPL_ARGS_LEVEL (partial_args,
12479 TMPL_ARGS_DEPTH (targs),
12480 make_tree_vec (DECL_NTPARMS (tmpl)));
12482 /* Disable access control as this function is used only during
12484 save_access_control = flag_access_control;
12485 flag_access_control = 0;
12487 ++processing_template_decl;
12488 /* Now, do the (partial) substitution to figure out the
12489 appropriate function type. */
12490 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
12491 --processing_template_decl;
12493 /* Substitute into the template parameters to obtain the real
12494 innermost set of parameters. This step is important if the
12495 innermost set of template parameters contains value
12496 parameters whose types depend on outer template parameters. */
12497 TREE_VEC_LENGTH (partial_args)--;
12498 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
12500 flag_access_control = save_access_control;
12506 /* Return truthvalue if we're processing a template different from
12507 the last one involved in diagnostics. */
12509 problematic_instantiation_changed (void)
12511 return last_template_error_tick != tinst_level_tick;
12514 /* Remember current template involved in diagnostics. */
12516 record_last_problematic_instantiation (void)
12518 last_template_error_tick = tinst_level_tick;
12522 current_instantiation (void)
12524 return current_tinst_level;
12527 /* [temp.param] Check that template non-type parm TYPE is of an allowable
12528 type. Return zero for ok, nonzero for disallowed. Issue error and
12529 warning messages under control of COMPLAIN. */
12532 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
12534 if (INTEGRAL_TYPE_P (type))
12536 else if (POINTER_TYPE_P (type))
12538 else if (TYPE_PTR_TO_MEMBER_P (type))
12540 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
12542 else if (TREE_CODE (type) == TYPENAME_TYPE)
12545 if (complain & tf_error)
12546 error ("%q#T is not a valid type for a template constant parameter", type);
12550 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
12551 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
12554 dependent_type_p_r (tree type)
12560 A type is dependent if it is:
12562 -- a template parameter. Template template parameters are types
12563 for us (since TYPE_P holds true for them) so we handle
12565 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
12566 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
12568 /* -- a qualified-id with a nested-name-specifier which contains a
12569 class-name that names a dependent type or whose unqualified-id
12570 names a dependent type. */
12571 if (TREE_CODE (type) == TYPENAME_TYPE)
12573 /* -- a cv-qualified type where the cv-unqualified type is
12575 type = TYPE_MAIN_VARIANT (type);
12576 /* -- a compound type constructed from any dependent type. */
12577 if (TYPE_PTR_TO_MEMBER_P (type))
12578 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
12579 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
12581 else if (TREE_CODE (type) == POINTER_TYPE
12582 || TREE_CODE (type) == REFERENCE_TYPE)
12583 return dependent_type_p (TREE_TYPE (type));
12584 else if (TREE_CODE (type) == FUNCTION_TYPE
12585 || TREE_CODE (type) == METHOD_TYPE)
12589 if (dependent_type_p (TREE_TYPE (type)))
12591 for (arg_type = TYPE_ARG_TYPES (type);
12593 arg_type = TREE_CHAIN (arg_type))
12594 if (dependent_type_p (TREE_VALUE (arg_type)))
12598 /* -- an array type constructed from any dependent type or whose
12599 size is specified by a constant expression that is
12600 value-dependent. */
12601 if (TREE_CODE (type) == ARRAY_TYPE)
12603 if (TYPE_DOMAIN (type)
12604 && ((value_dependent_expression_p
12605 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
12606 || (type_dependent_expression_p
12607 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
12609 return dependent_type_p (TREE_TYPE (type));
12612 /* -- a template-id in which either the template name is a template
12614 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
12616 /* ... or any of the template arguments is a dependent type or
12617 an expression that is type-dependent or value-dependent. */
12618 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
12619 && (any_dependent_template_arguments_p
12620 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
12623 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
12624 expression is not type-dependent, then it should already been
12626 if (TREE_CODE (type) == TYPEOF_TYPE)
12629 /* The standard does not specifically mention types that are local
12630 to template functions or local classes, but they should be
12631 considered dependent too. For example:
12633 template <int I> void f() {
12638 The size of `E' cannot be known until the value of `I' has been
12639 determined. Therefore, `E' must be considered dependent. */
12640 scope = TYPE_CONTEXT (type);
12641 if (scope && TYPE_P (scope))
12642 return dependent_type_p (scope);
12643 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12644 return type_dependent_expression_p (scope);
12646 /* Other types are non-dependent. */
12650 /* Returns TRUE if TYPE is dependent, in the sense of
12651 [temp.dep.type]. */
12654 dependent_type_p (tree type)
12656 /* If there are no template parameters in scope, then there can't be
12657 any dependent types. */
12658 if (!processing_template_decl)
12660 /* If we are not processing a template, then nobody should be
12661 providing us with a dependent type. */
12663 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM);
12667 /* If the type is NULL, we have not computed a type for the entity
12668 in question; in that case, the type is dependent. */
12672 /* Erroneous types can be considered non-dependent. */
12673 if (type == error_mark_node)
12676 /* If we have not already computed the appropriate value for TYPE,
12678 if (!TYPE_DEPENDENT_P_VALID (type))
12680 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12681 TYPE_DEPENDENT_P_VALID (type) = 1;
12684 return TYPE_DEPENDENT_P (type);
12687 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12690 dependent_scope_ref_p (tree expression, bool criterion (tree))
12695 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12697 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12700 scope = TREE_OPERAND (expression, 0);
12701 name = TREE_OPERAND (expression, 1);
12705 An id-expression is type-dependent if it contains a
12706 nested-name-specifier that contains a class-name that names a
12708 /* The suggested resolution to Core Issue 2 implies that if the
12709 qualifying type is the current class, then we must peek
12712 && currently_open_class (scope)
12713 && !criterion (name))
12715 if (dependent_type_p (scope))
12721 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12722 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
12726 value_dependent_expression_p (tree expression)
12728 if (!processing_template_decl)
12731 /* A name declared with a dependent type. */
12732 if (DECL_P (expression) && type_dependent_expression_p (expression))
12735 switch (TREE_CODE (expression))
12737 case IDENTIFIER_NODE:
12738 /* A name that has not been looked up -- must be dependent. */
12741 case TEMPLATE_PARM_INDEX:
12742 /* A non-type template parm. */
12746 /* A non-type template parm. */
12747 if (DECL_TEMPLATE_PARM_P (expression))
12752 /* A constant with integral or enumeration type and is initialized
12753 with an expression that is value-dependent. */
12754 if (DECL_INITIAL (expression)
12755 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12756 && value_dependent_expression_p (DECL_INITIAL (expression)))
12760 case DYNAMIC_CAST_EXPR:
12761 case STATIC_CAST_EXPR:
12762 case CONST_CAST_EXPR:
12763 case REINTERPRET_CAST_EXPR:
12765 /* These expressions are value-dependent if the type to which
12766 the cast occurs is dependent or the expression being casted
12767 is value-dependent. */
12769 tree type = TREE_TYPE (expression);
12771 if (dependent_type_p (type))
12774 /* A functional cast has a list of operands. */
12775 expression = TREE_OPERAND (expression, 0);
12778 /* If there are no operands, it must be an expression such
12779 as "int()". This should not happen for aggregate types
12780 because it would form non-constant expressions. */
12781 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12786 if (TREE_CODE (expression) == TREE_LIST)
12788 for (; expression; expression = TREE_CHAIN (expression))
12789 if (value_dependent_expression_p (TREE_VALUE (expression)))
12794 return value_dependent_expression_p (expression);
12799 /* A `sizeof' expression is value-dependent if the operand is
12801 expression = TREE_OPERAND (expression, 0);
12802 if (TYPE_P (expression))
12803 return dependent_type_p (expression);
12804 return type_dependent_expression_p (expression);
12807 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12809 case COMPONENT_REF:
12810 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12811 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12814 /* A CALL_EXPR may appear in a constant expression if it is a
12815 call to a builtin function, e.g., __builtin_constant_p. All
12816 such calls are value-dependent. */
12820 /* A constant expression is value-dependent if any subexpression is
12821 value-dependent. */
12822 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12824 case tcc_reference:
12826 return (value_dependent_expression_p
12827 (TREE_OPERAND (expression, 0)));
12829 case tcc_comparison:
12831 return ((value_dependent_expression_p
12832 (TREE_OPERAND (expression, 0)))
12833 || (value_dependent_expression_p
12834 (TREE_OPERAND (expression, 1))));
12836 case tcc_expression:
12839 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12840 /* In some cases, some of the operands may be missing.
12841 (For example, in the case of PREDECREMENT_EXPR, the
12842 amount to increment by may be missing.) That doesn't
12843 make the expression dependent. */
12844 if (TREE_OPERAND (expression, i)
12845 && (value_dependent_expression_p
12846 (TREE_OPERAND (expression, i))))
12856 /* The expression is not value-dependent. */
12860 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12861 [temp.dep.expr]. */
12864 type_dependent_expression_p (tree expression)
12866 if (!processing_template_decl)
12869 if (expression == error_mark_node)
12872 /* An unresolved name is always dependent. */
12873 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12876 /* Some expression forms are never type-dependent. */
12877 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12878 || TREE_CODE (expression) == SIZEOF_EXPR
12879 || TREE_CODE (expression) == ALIGNOF_EXPR
12880 || TREE_CODE (expression) == TYPEID_EXPR
12881 || TREE_CODE (expression) == DELETE_EXPR
12882 || TREE_CODE (expression) == VEC_DELETE_EXPR
12883 || TREE_CODE (expression) == THROW_EXPR)
12886 /* The types of these expressions depends only on the type to which
12887 the cast occurs. */
12888 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12889 || TREE_CODE (expression) == STATIC_CAST_EXPR
12890 || TREE_CODE (expression) == CONST_CAST_EXPR
12891 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12892 || TREE_CODE (expression) == CAST_EXPR)
12893 return dependent_type_p (TREE_TYPE (expression));
12895 /* The types of these expressions depends only on the type created
12896 by the expression. */
12897 if (TREE_CODE (expression) == NEW_EXPR
12898 || TREE_CODE (expression) == VEC_NEW_EXPR)
12900 /* For NEW_EXPR tree nodes created inside a template, either
12901 the object type itself or a TREE_LIST may appear as the
12903 tree type = TREE_OPERAND (expression, 1);
12904 if (TREE_CODE (type) == TREE_LIST)
12905 /* This is an array type. We need to check array dimensions
12907 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12908 || value_dependent_expression_p
12909 (TREE_OPERAND (TREE_VALUE (type), 1));
12911 return dependent_type_p (type);
12914 if (TREE_CODE (expression) == SCOPE_REF
12915 && dependent_scope_ref_p (expression,
12916 type_dependent_expression_p))
12919 if (TREE_CODE (expression) == FUNCTION_DECL
12920 && DECL_LANG_SPECIFIC (expression)
12921 && DECL_TEMPLATE_INFO (expression)
12922 && (any_dependent_template_arguments_p
12923 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12926 if (TREE_CODE (expression) == TEMPLATE_DECL
12927 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12930 if (TREE_TYPE (expression) == unknown_type_node)
12932 if (TREE_CODE (expression) == ADDR_EXPR)
12933 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12934 if (TREE_CODE (expression) == COMPONENT_REF
12935 || TREE_CODE (expression) == OFFSET_REF)
12937 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12939 expression = TREE_OPERAND (expression, 1);
12940 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12943 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12944 if (TREE_CODE (expression) == SCOPE_REF)
12947 if (TREE_CODE (expression) == BASELINK)
12948 expression = BASELINK_FUNCTIONS (expression);
12950 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12952 if (any_dependent_template_arguments_p
12953 (TREE_OPERAND (expression, 1)))
12955 expression = TREE_OPERAND (expression, 0);
12957 gcc_assert (TREE_CODE (expression) == OVERLOAD
12958 || TREE_CODE (expression) == FUNCTION_DECL);
12962 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12964 expression = OVL_NEXT (expression);
12969 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
12971 return (dependent_type_p (TREE_TYPE (expression)));
12974 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12975 contains a type-dependent expression. */
12978 any_type_dependent_arguments_p (tree args)
12982 tree arg = TREE_VALUE (args);
12984 if (type_dependent_expression_p (arg))
12986 args = TREE_CHAIN (args);
12991 /* Returns TRUE if the ARG (a template argument) is dependent. */
12994 dependent_template_arg_p (tree arg)
12996 if (!processing_template_decl)
12999 if (TREE_CODE (arg) == TEMPLATE_DECL
13000 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
13001 return dependent_template_p (arg);
13002 else if (TYPE_P (arg))
13003 return dependent_type_p (arg);
13005 return (type_dependent_expression_p (arg)
13006 || value_dependent_expression_p (arg));
13009 /* Returns true if ARGS (a collection of template arguments) contains
13010 any dependent arguments. */
13013 any_dependent_template_arguments_p (tree args)
13020 if (args == error_mark_node)
13023 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
13025 tree level = TMPL_ARGS_LEVEL (args, i + 1);
13026 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
13027 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
13034 /* Returns TRUE if the template TMPL is dependent. */
13037 dependent_template_p (tree tmpl)
13039 if (TREE_CODE (tmpl) == OVERLOAD)
13043 if (dependent_template_p (OVL_FUNCTION (tmpl)))
13045 tmpl = OVL_CHAIN (tmpl);
13050 /* Template template parameters are dependent. */
13051 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
13052 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
13054 /* So are names that have not been looked up. */
13055 if (TREE_CODE (tmpl) == SCOPE_REF
13056 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
13058 /* So are member templates of dependent classes. */
13059 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
13060 return dependent_type_p (DECL_CONTEXT (tmpl));
13064 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
13067 dependent_template_id_p (tree tmpl, tree args)
13069 return (dependent_template_p (tmpl)
13070 || any_dependent_template_arguments_p (args));
13073 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
13074 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
13075 can be found. Note that this function peers inside uninstantiated
13076 templates and therefore should be used only in extremely limited
13077 situations. ONLY_CURRENT_P restricts this peering to the currently
13078 open classes hierarchy (which is required when comparing types). */
13081 resolve_typename_type (tree type, bool only_current_p)
13089 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
13091 scope = TYPE_CONTEXT (type);
13092 name = TYPE_IDENTIFIER (type);
13094 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
13095 it first before we can figure out what NAME refers to. */
13096 if (TREE_CODE (scope) == TYPENAME_TYPE)
13097 scope = resolve_typename_type (scope, only_current_p);
13098 /* If we don't know what SCOPE refers to, then we cannot resolve the
13100 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
13101 return error_mark_node;
13102 /* If the SCOPE is a template type parameter, we have no way of
13103 resolving the name. */
13104 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
13106 /* If the SCOPE is not the current instantiation, there's no reason
13107 to look inside it. */
13108 if (only_current_p && !currently_open_class (scope))
13109 return error_mark_node;
13110 /* If SCOPE is a partial instantiation, it will not have a valid
13111 TYPE_FIELDS list, so use the original template. */
13112 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
13113 /* Enter the SCOPE so that name lookup will be resolved as if we
13114 were in the class definition. In particular, SCOPE will no
13115 longer be considered a dependent type. */
13116 pushed_scope = push_scope (scope);
13117 /* Look up the declaration. */
13118 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
13119 /* Obtain the set of qualifiers applied to the TYPE. */
13120 quals = cp_type_quals (type);
13121 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
13122 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
13124 type = error_mark_node;
13125 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
13126 && TREE_CODE (decl) == TYPE_DECL)
13127 type = TREE_TYPE (decl);
13128 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
13129 && DECL_CLASS_TEMPLATE_P (decl))
13133 /* Obtain the template and the arguments. */
13134 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
13135 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
13136 /* Instantiate the template. */
13137 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
13138 /*entering_scope=*/0, tf_error | tf_user);
13141 type = error_mark_node;
13142 /* Qualify the resulting type. */
13143 if (type != error_mark_node && quals)
13144 type = cp_build_qualified_type (type, quals);
13145 /* Leave the SCOPE. */
13147 pop_scope (pushed_scope);
13152 /* EXPR is an expression which is not type-dependent. Return a proxy
13153 for EXPR that can be used to compute the types of larger
13154 expressions containing EXPR. */
13157 build_non_dependent_expr (tree expr)
13161 /* Preserve null pointer constants so that the type of things like
13162 "p == 0" where "p" is a pointer can be determined. */
13163 if (null_ptr_cst_p (expr))
13165 /* Preserve OVERLOADs; the functions must be available to resolve
13168 if (TREE_CODE (inner_expr) == ADDR_EXPR)
13169 inner_expr = TREE_OPERAND (inner_expr, 0);
13170 if (TREE_CODE (inner_expr) == COMPONENT_REF)
13171 inner_expr = TREE_OPERAND (inner_expr, 1);
13172 if (is_overloaded_fn (inner_expr)
13173 || TREE_CODE (inner_expr) == OFFSET_REF)
13175 /* There is no need to return a proxy for a variable. */
13176 if (TREE_CODE (expr) == VAR_DECL)
13178 /* Preserve string constants; conversions from string constants to
13179 "char *" are allowed, even though normally a "const char *"
13180 cannot be used to initialize a "char *". */
13181 if (TREE_CODE (expr) == STRING_CST)
13183 /* Preserve arithmetic constants, as an optimization -- there is no
13184 reason to create a new node. */
13185 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
13187 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
13188 There is at least one place where we want to know that a
13189 particular expression is a throw-expression: when checking a ?:
13190 expression, there are special rules if the second or third
13191 argument is a throw-expression. */
13192 if (TREE_CODE (expr) == THROW_EXPR)
13195 if (TREE_CODE (expr) == COND_EXPR)
13196 return build3 (COND_EXPR,
13198 TREE_OPERAND (expr, 0),
13199 (TREE_OPERAND (expr, 1)
13200 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
13201 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
13202 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
13203 if (TREE_CODE (expr) == COMPOUND_EXPR
13204 && !COMPOUND_EXPR_OVERLOADED (expr))
13205 return build2 (COMPOUND_EXPR,
13207 TREE_OPERAND (expr, 0),
13208 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
13210 /* If the type is unknown, it can't really be non-dependent */
13211 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
13213 /* Otherwise, build a NON_DEPENDENT_EXPR.
13215 REFERENCE_TYPEs are not stripped for expressions in templates
13216 because doing so would play havoc with mangling. Consider, for
13219 template <typename T> void f<T& g>() { g(); }
13221 In the body of "f", the expression for "g" will have
13222 REFERENCE_TYPE, even though the standard says that it should
13223 not. The reason is that we must preserve the syntactic form of
13224 the expression so that mangling (say) "f<g>" inside the body of
13225 "f" works out correctly. Therefore, the REFERENCE_TYPE is
13227 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
13230 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
13231 Return a new TREE_LIST with the various arguments replaced with
13232 equivalent non-dependent expressions. */
13235 build_non_dependent_args (tree args)
13240 new_args = NULL_TREE;
13241 for (a = args; a; a = TREE_CHAIN (a))
13242 new_args = tree_cons (NULL_TREE,
13243 build_non_dependent_expr (TREE_VALUE (a)),
13245 return nreverse (new_args);
13248 #include "gt-cp-pt.h"