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 tree determine_specialization (tree, tree, tree *, int, int);
154 static int template_args_equal (tree, tree);
155 static void tsubst_default_arguments (tree);
156 static tree for_each_template_parm_r (tree *, int *, void *);
157 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
158 static void copy_default_args_to_explicit_spec (tree);
159 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
160 static int eq_local_specializations (const void *, const void *);
161 static bool dependent_type_p_r (tree);
162 static tree tsubst (tree, tree, tsubst_flags_t, tree);
163 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
164 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
166 /* Make the current scope suitable for access checking when we are
167 processing T. T can be FUNCTION_DECL for instantiated function
168 template, or VAR_DECL for static member variable (need by
169 instantiate_decl). */
172 push_access_scope (tree t)
174 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
175 || TREE_CODE (t) == VAR_DECL);
177 if (DECL_FRIEND_CONTEXT (t))
178 push_nested_class (DECL_FRIEND_CONTEXT (t));
179 else if (DECL_CLASS_SCOPE_P (t))
180 push_nested_class (DECL_CONTEXT (t));
182 push_to_top_level ();
184 if (TREE_CODE (t) == FUNCTION_DECL)
186 saved_access_scope = tree_cons
187 (NULL_TREE, current_function_decl, saved_access_scope);
188 current_function_decl = t;
192 /* Restore the scope set up by push_access_scope. T is the node we
196 pop_access_scope (tree t)
198 if (TREE_CODE (t) == FUNCTION_DECL)
200 current_function_decl = TREE_VALUE (saved_access_scope);
201 saved_access_scope = TREE_CHAIN (saved_access_scope);
204 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
207 pop_from_top_level ();
210 /* Do any processing required when DECL (a member template
211 declaration) is finished. Returns the TEMPLATE_DECL corresponding
212 to DECL, unless it is a specialization, in which case the DECL
213 itself is returned. */
216 finish_member_template_decl (tree decl)
218 if (decl == error_mark_node)
219 return error_mark_node;
221 gcc_assert (DECL_P (decl));
223 if (TREE_CODE (decl) == TYPE_DECL)
227 type = TREE_TYPE (decl);
228 if (IS_AGGR_TYPE (type)
229 && CLASSTYPE_TEMPLATE_INFO (type)
230 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
232 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
233 check_member_template (tmpl);
238 else if (TREE_CODE (decl) == FIELD_DECL)
239 error ("data member %qD cannot be a member template", decl);
240 else if (DECL_TEMPLATE_INFO (decl))
242 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
244 check_member_template (DECL_TI_TEMPLATE (decl));
245 return DECL_TI_TEMPLATE (decl);
251 error ("invalid member template declaration %qD", decl);
253 return error_mark_node;
256 /* Returns the template nesting level of the indicated class TYPE.
266 A<T>::B<U> has depth two, while A<T> has depth one.
267 Both A<T>::B<int> and A<int>::B<U> have depth one, if
268 they are instantiations, not specializations.
270 This function is guaranteed to return 0 if passed NULL_TREE so
271 that, for example, `template_class_depth (current_class_type)' is
275 template_class_depth (tree type)
280 type && TREE_CODE (type) != NAMESPACE_DECL;
281 type = (TREE_CODE (type) == FUNCTION_DECL)
282 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
284 if (TREE_CODE (type) != FUNCTION_DECL)
286 if (CLASSTYPE_TEMPLATE_INFO (type)
287 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
288 && uses_template_parms (CLASSTYPE_TI_ARGS (type)))
293 if (DECL_TEMPLATE_INFO (type)
294 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
295 && uses_template_parms (DECL_TI_ARGS (type)))
303 /* Returns 1 if processing DECL as part of do_pending_inlines
304 needs us to push template parms. */
307 inline_needs_template_parms (tree decl)
309 if (! DECL_TEMPLATE_INFO (decl))
312 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
313 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
316 /* Subroutine of maybe_begin_member_template_processing.
317 Push the template parms in PARMS, starting from LEVELS steps into the
318 chain, and ending at the beginning, since template parms are listed
322 push_inline_template_parms_recursive (tree parmlist, int levels)
324 tree parms = TREE_VALUE (parmlist);
328 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
330 ++processing_template_decl;
331 current_template_parms
332 = tree_cons (size_int (processing_template_decl),
333 parms, current_template_parms);
334 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
336 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
338 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
340 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
341 gcc_assert (DECL_P (parm));
343 switch (TREE_CODE (parm))
352 /* Make a CONST_DECL as is done in process_template_parm.
353 It is ugly that we recreate this here; the original
354 version built in process_template_parm is no longer
356 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
358 DECL_ARTIFICIAL (decl) = 1;
359 TREE_CONSTANT (decl) = 1;
360 TREE_INVARIANT (decl) = 1;
361 TREE_READONLY (decl) = 1;
362 DECL_INITIAL (decl) = DECL_INITIAL (parm);
363 SET_DECL_TEMPLATE_PARM_P (decl);
374 /* Restore the template parameter context for a member template or
375 a friend template defined in a class definition. */
378 maybe_begin_member_template_processing (tree decl)
383 if (inline_needs_template_parms (decl))
385 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
386 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
388 if (DECL_TEMPLATE_SPECIALIZATION (decl))
391 parms = TREE_CHAIN (parms);
394 push_inline_template_parms_recursive (parms, levels);
397 /* Remember how many levels of template parameters we pushed so that
398 we can pop them later. */
399 VEC_safe_push (int, heap, inline_parm_levels, levels);
402 /* Undo the effects of maybe_begin_member_template_processing. */
405 maybe_end_member_template_processing (void)
410 if (VEC_length (int, inline_parm_levels) == 0)
413 last = VEC_pop (int, inline_parm_levels);
414 for (i = 0; i < last; ++i)
416 --processing_template_decl;
417 current_template_parms = TREE_CHAIN (current_template_parms);
422 /* Return a new template argument vector which contains all of ARGS,
423 but has as its innermost set of arguments the EXTRA_ARGS. */
426 add_to_template_args (tree args, tree extra_args)
433 extra_depth = TMPL_ARGS_DEPTH (extra_args);
434 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
436 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
437 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
439 for (j = 1; j <= extra_depth; ++j, ++i)
440 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
445 /* Like add_to_template_args, but only the outermost ARGS are added to
446 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
447 (EXTRA_ARGS) levels are added. This function is used to combine
448 the template arguments from a partial instantiation with the
449 template arguments used to attain the full instantiation from the
450 partial instantiation. */
453 add_outermost_template_args (tree args, tree extra_args)
457 /* If there are more levels of EXTRA_ARGS than there are ARGS,
458 something very fishy is going on. */
459 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
461 /* If *all* the new arguments will be the EXTRA_ARGS, just return
463 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
466 /* For the moment, we make ARGS look like it contains fewer levels. */
467 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
469 new_args = add_to_template_args (args, extra_args);
471 /* Now, we restore ARGS to its full dimensions. */
472 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
477 /* Return the N levels of innermost template arguments from the ARGS. */
480 get_innermost_template_args (tree args, int n)
488 /* If N is 1, just return the innermost set of template arguments. */
490 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
492 /* If we're not removing anything, just return the arguments we were
494 extra_levels = TMPL_ARGS_DEPTH (args) - n;
495 gcc_assert (extra_levels >= 0);
496 if (extra_levels == 0)
499 /* Make a new set of arguments, not containing the outer arguments. */
500 new_args = make_tree_vec (n);
501 for (i = 1; i <= n; ++i)
502 SET_TMPL_ARGS_LEVEL (new_args, i,
503 TMPL_ARGS_LEVEL (args, i + extra_levels));
508 /* We've got a template header coming up; push to a new level for storing
512 begin_template_parm_list (void)
514 /* We use a non-tag-transparent scope here, which causes pushtag to
515 put tags in this scope, rather than in the enclosing class or
516 namespace scope. This is the right thing, since we want
517 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
518 global template class, push_template_decl handles putting the
519 TEMPLATE_DECL into top-level scope. For a nested template class,
522 template <class T> struct S1 {
523 template <class T> struct S2 {};
526 pushtag contains special code to call pushdecl_with_scope on the
527 TEMPLATE_DECL for S2. */
528 begin_scope (sk_template_parms, NULL);
529 ++processing_template_decl;
530 ++processing_template_parmlist;
531 note_template_header (0);
534 /* This routine is called when a specialization is declared. If it is
535 invalid to declare a specialization here, an error is reported. */
538 check_specialization_scope (void)
540 tree scope = current_scope ();
544 An explicit specialization shall be declared in the namespace of
545 which the template is a member, or, for member templates, in the
546 namespace of which the enclosing class or enclosing class
547 template is a member. An explicit specialization of a member
548 function, member class or static data member of a class template
549 shall be declared in the namespace of which the class template
551 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
552 error ("explicit specialization in non-namespace scope %qD", scope);
556 In an explicit specialization declaration for a member of a class
557 template or a member template that appears in namespace scope,
558 the member template and some of its enclosing class templates may
559 remain unspecialized, except that the declaration shall not
560 explicitly specialize a class member template if its enclosing
561 class templates are not explicitly specialized as well. */
562 if (current_template_parms)
563 error ("enclosing class templates are not explicitly specialized");
566 /* We've just seen template <>. */
569 begin_specialization (void)
571 begin_scope (sk_template_spec, NULL);
572 note_template_header (1);
573 check_specialization_scope ();
576 /* Called at then end of processing a declaration preceded by
580 end_specialization (void)
583 reset_specialization ();
586 /* Any template <>'s that we have seen thus far are not referring to a
587 function specialization. */
590 reset_specialization (void)
592 processing_specialization = 0;
593 template_header_count = 0;
596 /* We've just seen a template header. If SPECIALIZATION is nonzero,
597 it was of the form template <>. */
600 note_template_header (int specialization)
602 processing_specialization = specialization;
603 template_header_count++;
606 /* We're beginning an explicit instantiation. */
609 begin_explicit_instantiation (void)
611 gcc_assert (!processing_explicit_instantiation);
612 processing_explicit_instantiation = true;
617 end_explicit_instantiation (void)
619 gcc_assert (processing_explicit_instantiation);
620 processing_explicit_instantiation = false;
623 /* An explicit specialization or partial specialization TMPL is being
624 declared. Check that the namespace in which the specialization is
625 occurring is permissible. Returns false iff it is invalid to
626 specialize TMPL in the current namespace. */
629 check_specialization_namespace (tree tmpl)
631 tree tpl_ns = decl_namespace_context (tmpl);
635 An explicit specialization shall be declared in the namespace of
636 which the template is a member, or, for member templates, in the
637 namespace of which the enclosing class or enclosing class
638 template is a member. An explicit specialization of a member
639 function, member class or static data member of a class template
640 shall be declared in the namespace of which the class template is
642 if (is_associated_namespace (current_namespace, tpl_ns))
643 /* Same or super-using namespace. */
647 pedwarn ("specialization of %qD in different namespace", tmpl);
648 pedwarn (" from definition of %q+#D", tmpl);
653 /* SPEC is an explicit instantiation. Check that it is valid to
654 perform this explicit instantiation in the current namespace. */
657 check_explicit_instantiation_namespace (tree spec)
661 /* DR 275: An explicit instantiation shall appear in an enclosing
662 namespace of its template. */
663 ns = decl_namespace_context (spec);
664 if (!is_ancestor (current_namespace, ns))
665 pedwarn ("explicit instantiation of %qD in namespace %qD "
666 "(which does not enclose namespace %qD)",
667 spec, current_namespace, ns);
670 /* The TYPE is being declared. If it is a template type, that means it
671 is a partial specialization. Do appropriate error-checking. */
674 maybe_process_partial_specialization (tree type)
678 if (type == error_mark_node)
681 context = TYPE_CONTEXT (type);
683 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
685 /* This is for ordinary explicit specialization and partial
686 specialization of a template class such as:
688 template <> class C<int>;
692 template <class T> class C<T*>;
694 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
696 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
697 && !COMPLETE_TYPE_P (type))
699 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
700 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
701 if (processing_template_decl)
702 push_template_decl (TYPE_MAIN_DECL (type));
704 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
705 error ("specialization of %qT after instantiation", type);
707 else if (CLASS_TYPE_P (type)
708 && !CLASSTYPE_USE_TEMPLATE (type)
709 && CLASSTYPE_TEMPLATE_INFO (type)
710 && context && CLASS_TYPE_P (context)
711 && CLASSTYPE_TEMPLATE_INFO (context))
713 /* This is for an explicit specialization of member class
714 template according to [temp.expl.spec/18]:
716 template <> template <class U> class C<int>::D;
718 The context `C<int>' must be an implicit instantiation.
719 Otherwise this is just a member class template declared
722 template <> class C<int> { template <class U> class D; };
723 template <> template <class U> class C<int>::D;
725 In the first case, `C<int>::D' is a specialization of `C<T>::D'
726 while in the second case, `C<int>::D' is a primary template
727 and `C<T>::D' may not exist. */
729 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
730 && !COMPLETE_TYPE_P (type))
734 if (current_namespace
735 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
737 pedwarn ("specializing %q#T in different namespace", type);
738 pedwarn (" from definition of %q+#D",
739 CLASSTYPE_TI_TEMPLATE (type));
742 /* Check for invalid specialization after instantiation:
744 template <> template <> class C<int>::D<int>;
745 template <> template <class U> class C<int>::D; */
747 for (t = DECL_TEMPLATE_INSTANTIATIONS
748 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
749 t; t = TREE_CHAIN (t))
750 if (TREE_VALUE (t) != type
751 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
752 error ("specialization %qT after instantiation %qT",
753 type, TREE_VALUE (t));
755 /* Mark TYPE as a specialization. And as a result, we only
756 have one level of template argument for the innermost
758 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
759 CLASSTYPE_TI_ARGS (type)
760 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
763 else if (processing_specialization)
764 error ("explicit specialization of non-template %qT", type);
767 /* Returns nonzero if we can optimize the retrieval of specializations
768 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
769 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
772 optimize_specialization_lookup_p (tree tmpl)
774 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
775 && DECL_CLASS_SCOPE_P (tmpl)
776 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
778 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
779 /* The optimized lookup depends on the fact that the
780 template arguments for the member function template apply
781 purely to the containing class, which is not true if the
782 containing class is an explicit or partial
784 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
785 && !DECL_MEMBER_TEMPLATE_P (tmpl)
786 && !DECL_CONV_FN_P (tmpl)
787 /* It is possible to have a template that is not a member
788 template and is not a member of a template class:
790 template <typename T>
791 struct S { friend A::f(); };
793 Here, the friend function is a template, but the context does
794 not have template information. The optimized lookup relies
795 on having ARGS be the template arguments for both the class
796 and the function template. */
797 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
800 /* Retrieve the specialization (in the sense of [temp.spec] - a
801 specialization is either an instantiation or an explicit
802 specialization) of TMPL for the given template ARGS. If there is
803 no such specialization, return NULL_TREE. The ARGS are a vector of
804 arguments, or a vector of vectors of arguments, in the case of
805 templates with more than one level of parameters.
807 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
808 then we search for a partial specialization matching ARGS. This
809 parameter is ignored if TMPL is not a class template. */
812 retrieve_specialization (tree tmpl, tree args,
813 bool class_specializations_p)
815 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
817 /* There should be as many levels of arguments as there are
818 levels of parameters. */
819 gcc_assert (TMPL_ARGS_DEPTH (args)
820 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
822 if (optimize_specialization_lookup_p (tmpl))
825 tree class_specialization;
826 VEC(tree,gc) *methods;
830 /* The template arguments actually apply to the containing
831 class. Find the class specialization with those
833 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
835 = retrieve_specialization (class_template, args,
836 /*class_specializations_p=*/false);
837 if (!class_specialization)
839 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
840 for the specialization. */
841 idx = class_method_index_for_fn (class_specialization, tmpl);
844 /* Iterate through the methods with the indicated name, looking
845 for the one that has an instance of TMPL. */
846 methods = CLASSTYPE_METHOD_VEC (class_specialization);
847 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
849 tree fn = OVL_CURRENT (fns);
850 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
860 /* Class templates store their instantiations on the
861 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
862 DECL_TEMPLATE_SPECIALIZATIONS list. */
863 if (!class_specializations_p
864 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
865 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
867 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
869 /* Iterate through the list until we find a matching template. */
870 while (*sp != NULL_TREE)
874 if (comp_template_args (TREE_PURPOSE (spec), args))
876 /* Use the move-to-front heuristic to speed up future
880 *sp = TREE_CHAIN (*sp);
881 TREE_CHAIN (spec) = *head;
884 return TREE_VALUE (spec);
886 sp = &TREE_CHAIN (spec);
893 /* Like retrieve_specialization, but for local declarations. */
896 retrieve_local_specialization (tree tmpl)
898 tree spec = (tree) htab_find_with_hash (local_specializations, tmpl,
899 htab_hash_pointer (tmpl));
900 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
903 /* Returns nonzero iff DECL is a specialization of TMPL. */
906 is_specialization_of (tree decl, tree tmpl)
910 if (TREE_CODE (decl) == FUNCTION_DECL)
914 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
920 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
922 for (t = TREE_TYPE (decl);
924 t = CLASSTYPE_USE_TEMPLATE (t)
925 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
926 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
933 /* Returns nonzero iff DECL is a specialization of friend declaration
934 FRIEND according to [temp.friend]. */
937 is_specialization_of_friend (tree decl, tree friend)
939 bool need_template = true;
942 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
943 || TREE_CODE (decl) == TYPE_DECL);
945 /* For [temp.friend/6] when FRIEND is an ordinary member function
946 of a template class, we want to check if DECL is a specialization
948 if (TREE_CODE (friend) == FUNCTION_DECL
949 && DECL_TEMPLATE_INFO (friend)
950 && !DECL_USE_TEMPLATE (friend))
952 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
953 friend = DECL_TI_TEMPLATE (friend);
954 need_template = false;
956 else if (TREE_CODE (friend) == TEMPLATE_DECL
957 && !PRIMARY_TEMPLATE_P (friend))
958 need_template = false;
960 /* There is nothing to do if this is not a template friend. */
961 if (TREE_CODE (friend) != TEMPLATE_DECL)
964 if (is_specialization_of (decl, friend))
968 A member of a class template may be declared to be a friend of a
969 non-template class. In this case, the corresponding member of
970 every specialization of the class template is a friend of the
971 class granting friendship.
973 For example, given a template friend declaration
975 template <class T> friend void A<T>::f();
977 the member function below is considered a friend
979 template <> struct A<int> {
983 For this type of template friend, TEMPLATE_DEPTH below will be
984 nonzero. To determine if DECL is a friend of FRIEND, we first
985 check if the enclosing class is a specialization of another. */
987 template_depth = template_class_depth (DECL_CONTEXT (friend));
989 && DECL_CLASS_SCOPE_P (decl)
990 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
991 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
993 /* Next, we check the members themselves. In order to handle
994 a few tricky cases, such as when FRIEND's are
996 template <class T> friend void A<T>::g(T t);
997 template <class T> template <T t> friend void A<T>::h();
1001 void A<int>::g(int);
1002 template <int> void A<int>::h();
1004 we need to figure out ARGS, the template arguments from
1005 the context of DECL. This is required for template substitution
1006 of `T' in the function parameter of `g' and template parameter
1007 of `h' in the above examples. Here ARGS corresponds to `int'. */
1009 tree context = DECL_CONTEXT (decl);
1010 tree args = NULL_TREE;
1011 int current_depth = 0;
1013 while (current_depth < template_depth)
1015 if (CLASSTYPE_TEMPLATE_INFO (context))
1017 if (current_depth == 0)
1018 args = TYPE_TI_ARGS (context);
1020 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1023 context = TYPE_CONTEXT (context);
1026 if (TREE_CODE (decl) == FUNCTION_DECL)
1031 tree friend_args_type;
1032 tree decl_args_type;
1034 /* Make sure that both DECL and FRIEND are templates or
1036 is_template = DECL_TEMPLATE_INFO (decl)
1037 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1038 if (need_template ^ is_template)
1040 else if (is_template)
1042 /* If both are templates, check template parameter list. */
1044 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1046 if (!comp_template_parms
1047 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1051 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1054 decl_type = TREE_TYPE (decl);
1056 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1057 tf_none, NULL_TREE);
1058 if (friend_type == error_mark_node)
1061 /* Check if return types match. */
1062 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1065 /* Check if function parameter types match, ignoring the
1066 `this' parameter. */
1067 friend_args_type = TYPE_ARG_TYPES (friend_type);
1068 decl_args_type = TYPE_ARG_TYPES (decl_type);
1069 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1070 friend_args_type = TREE_CHAIN (friend_args_type);
1071 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1072 decl_args_type = TREE_CHAIN (decl_args_type);
1074 return compparms (decl_args_type, friend_args_type);
1078 /* DECL is a TYPE_DECL */
1080 tree decl_type = TREE_TYPE (decl);
1082 /* Make sure that both DECL and FRIEND are templates or
1085 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1086 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1088 if (need_template ^ is_template)
1090 else if (is_template)
1093 /* If both are templates, check the name of the two
1094 TEMPLATE_DECL's first because is_friend didn't. */
1095 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1096 != DECL_NAME (friend))
1099 /* Now check template parameter list. */
1101 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1103 return comp_template_parms
1104 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1108 return (DECL_NAME (decl)
1109 == DECL_NAME (friend));
1115 /* Register the specialization SPEC as a specialization of TMPL with
1116 the indicated ARGS. IS_FRIEND indicates whether the specialization
1117 is actually just a friend declaration. Returns SPEC, or an
1118 equivalent prior declaration, if available. */
1121 register_specialization (tree spec, tree tmpl, tree args, bool is_friend)
1125 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1127 if (TREE_CODE (spec) == FUNCTION_DECL
1128 && uses_template_parms (DECL_TI_ARGS (spec)))
1129 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1130 register it; we want the corresponding TEMPLATE_DECL instead.
1131 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1132 the more obvious `uses_template_parms (spec)' to avoid problems
1133 with default function arguments. In particular, given
1134 something like this:
1136 template <class T> void f(T t1, T t = T())
1138 the default argument expression is not substituted for in an
1139 instantiation unless and until it is actually needed. */
1142 fn = retrieve_specialization (tmpl, args,
1143 /*class_specializations_p=*/false);
1144 /* We can sometimes try to re-register a specialization that we've
1145 already got. In particular, regenerate_decl_from_template calls
1146 duplicate_decls which will update the specialization list. But,
1147 we'll still get called again here anyhow. It's more convenient
1148 to simply allow this than to try to prevent it. */
1151 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1153 if (DECL_TEMPLATE_INSTANTIATION (fn))
1156 || DECL_EXPLICIT_INSTANTIATION (fn))
1158 error ("specialization of %qD after instantiation",
1165 /* This situation should occur only if the first
1166 specialization is an implicit instantiation, the
1167 second is an explicit specialization, and the
1168 implicit instantiation has not yet been used. That
1169 situation can occur if we have implicitly
1170 instantiated a member function and then specialized
1173 We can also wind up here if a friend declaration that
1174 looked like an instantiation turns out to be a
1177 template <class T> void foo(T);
1178 class S { friend void foo<>(int) };
1179 template <> void foo(int);
1181 We transform the existing DECL in place so that any
1182 pointers to it become pointers to the updated
1185 If there was a definition for the template, but not
1186 for the specialization, we want this to look as if
1187 there were no definition, and vice versa. */
1188 DECL_INITIAL (fn) = NULL_TREE;
1189 duplicate_decls (spec, fn, is_friend);
1190 /* The call to duplicate_decls will have applied
1193 An explicit specialization of a function template
1194 is inline only if it is explicitly declared to be,
1195 and independently of whether its function template
1198 to the primary function; now copy the inline bits to
1199 the various clones. */
1200 FOR_EACH_CLONE (clone, fn)
1202 DECL_DECLARED_INLINE_P (clone)
1203 = DECL_DECLARED_INLINE_P (fn);
1207 check_specialization_namespace (fn);
1212 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1214 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1215 /* Dup decl failed, but this is a new definition. Set the
1216 line number so any errors match this new
1218 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1224 /* A specialization must be declared in the same namespace as the
1225 template it is specializing. */
1226 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1227 && !check_specialization_namespace (tmpl))
1228 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1230 if (!optimize_specialization_lookup_p (tmpl))
1231 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1232 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1237 /* Unregister the specialization SPEC as a specialization of TMPL.
1238 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1239 if the SPEC was listed as a specialization of TMPL. */
1242 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1246 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1248 s = &TREE_CHAIN (*s))
1249 if (TREE_VALUE (*s) == spec)
1252 *s = TREE_CHAIN (*s);
1254 TREE_VALUE (*s) = new_spec;
1261 /* Compare an entry in the local specializations hash table P1 (which
1262 is really a pointer to a TREE_LIST) with P2 (which is really a
1266 eq_local_specializations (const void *p1, const void *p2)
1268 return TREE_VALUE ((tree) p1) == (tree) p2;
1271 /* Hash P1, an entry in the local specializations table. */
1274 hash_local_specialization (const void* p1)
1276 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1279 /* Like register_specialization, but for local declarations. We are
1280 registering SPEC, an instantiation of TMPL. */
1283 register_local_specialization (tree spec, tree tmpl)
1287 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1288 htab_hash_pointer (tmpl), INSERT);
1289 *slot = build_tree_list (spec, tmpl);
1292 /* Print the list of candidate FNS in an error message. */
1295 print_candidates (tree fns)
1299 const char *str = "candidates are:";
1301 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1305 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1306 error ("%s %+#D", str, OVL_CURRENT (f));
1311 /* Returns the template (one of the functions given by TEMPLATE_ID)
1312 which can be specialized to match the indicated DECL with the
1313 explicit template args given in TEMPLATE_ID. The DECL may be
1314 NULL_TREE if none is available. In that case, the functions in
1315 TEMPLATE_ID are non-members.
1317 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1318 specialization of a member template.
1320 The TEMPLATE_COUNT is the number of references to qualifying
1321 template classes that appeared in the name of the function. See
1322 check_explicit_specialization for a more accurate description.
1324 The template args (those explicitly specified and those deduced)
1325 are output in a newly created vector *TARGS_OUT.
1327 If it is impossible to determine the result, an error message is
1328 issued. The error_mark_node is returned to indicate failure. */
1331 determine_specialization (tree template_id,
1334 int need_member_template,
1339 tree explicit_targs;
1340 tree candidates = NULL_TREE;
1341 /* A TREE_LIST of templates of which DECL may be a specialization.
1342 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1343 corresponding TREE_PURPOSE is the set of template arguments that,
1344 when used to instantiate the template, would produce a function
1345 with the signature of DECL. */
1346 tree templates = NULL_TREE;
1348 struct cp_binding_level *b;
1350 *targs_out = NULL_TREE;
1352 if (template_id == error_mark_node)
1353 return error_mark_node;
1355 fns = TREE_OPERAND (template_id, 0);
1356 explicit_targs = TREE_OPERAND (template_id, 1);
1358 if (fns == error_mark_node)
1359 return error_mark_node;
1361 /* Check for baselinks. */
1362 if (BASELINK_P (fns))
1363 fns = BASELINK_FUNCTIONS (fns);
1365 if (!is_overloaded_fn (fns))
1367 error ("%qD is not a function template", fns);
1368 return error_mark_node;
1371 /* Count the number of template headers specified for this
1374 for (b = current_binding_level;
1375 b->kind == sk_template_parms;
1379 for (; fns; fns = OVL_NEXT (fns))
1381 tree fn = OVL_CURRENT (fns);
1383 if (TREE_CODE (fn) == TEMPLATE_DECL)
1385 tree decl_arg_types;
1388 /* DECL might be a specialization of FN. */
1390 /* Adjust the type of DECL in case FN is a static member. */
1391 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1392 if (DECL_STATIC_FUNCTION_P (fn)
1393 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1394 decl_arg_types = TREE_CHAIN (decl_arg_types);
1396 /* Check that the number of function parameters matches.
1398 template <class T> void f(int i = 0);
1399 template <> void f<int>();
1400 The specialization f<int> is invalid but is not caught
1401 by get_bindings below. */
1403 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1404 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1407 /* For a non-static member function, we need to make sure that
1408 the const qualification is the same. This can be done by
1409 checking the 'this' in the argument list. */
1410 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1411 && !same_type_p (TREE_VALUE (fn_arg_types),
1412 TREE_VALUE (decl_arg_types)))
1415 /* In case of explicit specialization, we need to check if
1416 the number of template headers appearing in the specialization
1417 is correct. This is usually done in check_explicit_specialization,
1418 but the check done there cannot be exhaustive when specializing
1419 member functions. Consider the following code:
1421 template <> void A<int>::f(int);
1422 template <> template <> void A<int>::f(int);
1424 Assuming that A<int> is not itself an explicit specialization
1425 already, the first line specializes "f" which is a non-template
1426 member function, whilst the second line specializes "f" which
1427 is a template member function. So both lines are syntactically
1428 correct, and check_explicit_specialization does not reject
1431 Here, we can do better, as we are matching the specialization
1432 against the declarations. We count the number of template
1433 headers, and we check if they match TEMPLATE_COUNT + 1
1434 (TEMPLATE_COUNT is the number of qualifying template classes,
1435 plus there must be another header for the member template
1438 Notice that if header_count is zero, this is not a
1439 specialization but rather a template instantiation, so there
1440 is no check we can perform here. */
1441 if (header_count && header_count != template_count + 1)
1444 /* Check that the number of template arguments at the
1445 innermost level for DECL is the same as for FN. */
1446 if (current_binding_level->kind == sk_template_parms
1447 && !current_binding_level->explicit_spec_p
1448 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1449 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1450 (current_template_parms))))
1453 /* See whether this function might be a specialization of this
1455 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1458 /* We cannot deduce template arguments that when used to
1459 specialize TMPL will produce DECL. */
1462 /* Save this template, and the arguments deduced. */
1463 templates = tree_cons (targs, fn, templates);
1465 else if (need_member_template)
1466 /* FN is an ordinary member function, and we need a
1467 specialization of a member template. */
1469 else if (TREE_CODE (fn) != FUNCTION_DECL)
1470 /* We can get IDENTIFIER_NODEs here in certain erroneous
1473 else if (!DECL_FUNCTION_MEMBER_P (fn))
1474 /* This is just an ordinary non-member function. Nothing can
1475 be a specialization of that. */
1477 else if (DECL_ARTIFICIAL (fn))
1478 /* Cannot specialize functions that are created implicitly. */
1482 tree decl_arg_types;
1484 /* This is an ordinary member function. However, since
1485 we're here, we can assume it's enclosing class is a
1486 template class. For example,
1488 template <typename T> struct S { void f(); };
1489 template <> void S<int>::f() {}
1491 Here, S<int>::f is a non-template, but S<int> is a
1492 template class. If FN has the same type as DECL, we
1493 might be in business. */
1495 if (!DECL_TEMPLATE_INFO (fn))
1496 /* Its enclosing class is an explicit specialization
1497 of a template class. This is not a candidate. */
1500 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1501 TREE_TYPE (TREE_TYPE (fn))))
1502 /* The return types differ. */
1505 /* Adjust the type of DECL in case FN is a static member. */
1506 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1507 if (DECL_STATIC_FUNCTION_P (fn)
1508 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1509 decl_arg_types = TREE_CHAIN (decl_arg_types);
1511 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1514 candidates = tree_cons (NULL_TREE, fn, candidates);
1518 if (templates && TREE_CHAIN (templates))
1524 It is possible for a specialization with a given function
1525 signature to be instantiated from more than one function
1526 template. In such cases, explicit specification of the
1527 template arguments must be used to uniquely identify the
1528 function template specialization being specialized.
1530 Note that here, there's no suggestion that we're supposed to
1531 determine which of the candidate templates is most
1532 specialized. However, we, also have:
1536 Partial ordering of overloaded function template
1537 declarations is used in the following contexts to select
1538 the function template to which a function template
1539 specialization refers:
1541 -- when an explicit specialization refers to a function
1544 So, we do use the partial ordering rules, at least for now.
1545 This extension can only serve to make invalid programs valid,
1546 so it's safe. And, there is strong anecdotal evidence that
1547 the committee intended the partial ordering rules to apply;
1548 the EDG front-end has that behavior, and John Spicer claims
1549 that the committee simply forgot to delete the wording in
1550 [temp.expl.spec]. */
1551 tree tmpl = most_specialized_instantiation (templates);
1552 if (tmpl != error_mark_node)
1555 TREE_CHAIN (templates) = NULL_TREE;
1559 if (templates == NULL_TREE && candidates == NULL_TREE)
1561 error ("template-id %qD for %q+D does not match any template "
1562 "declaration", template_id, decl);
1563 return error_mark_node;
1565 else if ((templates && TREE_CHAIN (templates))
1566 || (candidates && TREE_CHAIN (candidates))
1567 || (templates && candidates))
1569 error ("ambiguous template specialization %qD for %q+D",
1571 chainon (candidates, templates);
1572 print_candidates (candidates);
1573 return error_mark_node;
1576 /* We have one, and exactly one, match. */
1579 /* It was a specialization of an ordinary member function in a
1581 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1582 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1585 /* It was a specialization of a template. */
1586 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1587 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1589 *targs_out = copy_node (targs);
1590 SET_TMPL_ARGS_LEVEL (*targs_out,
1591 TMPL_ARGS_DEPTH (*targs_out),
1592 TREE_PURPOSE (templates));
1595 *targs_out = TREE_PURPOSE (templates);
1596 return TREE_VALUE (templates);
1599 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1600 but with the default argument values filled in from those in the
1604 copy_default_args_to_explicit_spec_1 (tree spec_types,
1607 tree new_spec_types;
1612 if (spec_types == void_list_node)
1613 return void_list_node;
1615 /* Substitute into the rest of the list. */
1617 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1618 TREE_CHAIN (tmpl_types));
1620 /* Add the default argument for this parameter. */
1621 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1622 TREE_VALUE (spec_types),
1626 /* DECL is an explicit specialization. Replicate default arguments
1627 from the template it specializes. (That way, code like:
1629 template <class T> void f(T = 3);
1630 template <> void f(double);
1633 works, as required.) An alternative approach would be to look up
1634 the correct default arguments at the call-site, but this approach
1635 is consistent with how implicit instantiations are handled. */
1638 copy_default_args_to_explicit_spec (tree decl)
1643 tree new_spec_types;
1647 tree object_type = NULL_TREE;
1648 tree in_charge = NULL_TREE;
1649 tree vtt = NULL_TREE;
1651 /* See if there's anything we need to do. */
1652 tmpl = DECL_TI_TEMPLATE (decl);
1653 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1654 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1655 if (TREE_PURPOSE (t))
1660 old_type = TREE_TYPE (decl);
1661 spec_types = TYPE_ARG_TYPES (old_type);
1663 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1665 /* Remove the this pointer, but remember the object's type for
1667 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1668 spec_types = TREE_CHAIN (spec_types);
1669 tmpl_types = TREE_CHAIN (tmpl_types);
1671 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1673 /* DECL may contain more parameters than TMPL due to the extra
1674 in-charge parameter in constructors and destructors. */
1675 in_charge = spec_types;
1676 spec_types = TREE_CHAIN (spec_types);
1678 if (DECL_HAS_VTT_PARM_P (decl))
1681 spec_types = TREE_CHAIN (spec_types);
1685 /* Compute the merged default arguments. */
1687 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1689 /* Compute the new FUNCTION_TYPE. */
1693 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1698 /* Put the in-charge parameter back. */
1699 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1700 TREE_VALUE (in_charge),
1703 new_type = build_method_type_directly (object_type,
1704 TREE_TYPE (old_type),
1708 new_type = build_function_type (TREE_TYPE (old_type),
1710 new_type = cp_build_type_attribute_variant (new_type,
1711 TYPE_ATTRIBUTES (old_type));
1712 new_type = build_exception_variant (new_type,
1713 TYPE_RAISES_EXCEPTIONS (old_type));
1714 TREE_TYPE (decl) = new_type;
1717 /* Check to see if the function just declared, as indicated in
1718 DECLARATOR, and in DECL, is a specialization of a function
1719 template. We may also discover that the declaration is an explicit
1720 instantiation at this point.
1722 Returns DECL, or an equivalent declaration that should be used
1723 instead if all goes well. Issues an error message if something is
1724 amiss. Returns error_mark_node if the error is not easily
1727 FLAGS is a bitmask consisting of the following flags:
1729 2: The function has a definition.
1730 4: The function is a friend.
1732 The TEMPLATE_COUNT is the number of references to qualifying
1733 template classes that appeared in the name of the function. For
1736 template <class T> struct S { void f(); };
1739 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1740 classes are not counted in the TEMPLATE_COUNT, so that in
1742 template <class T> struct S {};
1743 template <> struct S<int> { void f(); }
1744 template <> void S<int>::f();
1746 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1747 invalid; there should be no template <>.)
1749 If the function is a specialization, it is marked as such via
1750 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1751 is set up correctly, and it is added to the list of specializations
1752 for that template. */
1755 check_explicit_specialization (tree declarator,
1760 int have_def = flags & 2;
1761 int is_friend = flags & 4;
1762 int specialization = 0;
1763 int explicit_instantiation = 0;
1764 int member_specialization = 0;
1765 tree ctype = DECL_CLASS_CONTEXT (decl);
1766 tree dname = DECL_NAME (decl);
1771 if (!processing_specialization)
1774 tsk = tsk_excessive_parms;
1777 tsk = current_tmpl_spec_kind (template_count);
1782 if (processing_specialization)
1785 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1787 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1790 /* This could be something like:
1792 template <class T> void f(T);
1793 class S { friend void f<>(int); } */
1797 /* This case handles bogus declarations like template <>
1798 template <class T> void f<int>(); */
1800 error ("template-id %qD in declaration of primary template",
1807 case tsk_invalid_member_spec:
1808 /* The error has already been reported in
1809 check_specialization_scope. */
1810 return error_mark_node;
1812 case tsk_invalid_expl_inst:
1813 error ("template parameter list used in explicit instantiation");
1819 error ("definition provided for explicit instantiation");
1821 explicit_instantiation = 1;
1824 case tsk_excessive_parms:
1825 case tsk_insufficient_parms:
1826 if (tsk == tsk_excessive_parms)
1827 error ("too many template parameter lists in declaration of %qD",
1829 else if (template_header_count)
1830 error("too few template parameter lists in declaration of %qD", decl);
1832 error("explicit specialization of %qD must be introduced by "
1833 "%<template <>%>", decl);
1837 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1839 member_specialization = 1;
1845 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1847 /* This case handles bogus declarations like template <>
1848 template <class T> void f<int>(); */
1850 if (uses_template_parms (declarator))
1851 error ("function template partial specialization %qD "
1852 "is not allowed", declarator);
1854 error ("template-id %qD in declaration of primary template",
1859 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1860 /* This is a specialization of a member template, without
1861 specialization the containing class. Something like:
1863 template <class T> struct S {
1864 template <class U> void f (U);
1866 template <> template <class U> void S<int>::f(U) {}
1868 That's a specialization -- but of the entire template. */
1876 if (specialization || member_specialization)
1878 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1879 for (; t; t = TREE_CHAIN (t))
1880 if (TREE_PURPOSE (t))
1883 ("default argument specified in explicit specialization");
1888 if (specialization || member_specialization || explicit_instantiation)
1890 tree tmpl = NULL_TREE;
1891 tree targs = NULL_TREE;
1893 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1894 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1898 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1903 /* If there is no class context, the explicit instantiation
1904 must be at namespace scope. */
1905 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1907 /* Find the namespace binding, using the declaration
1909 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
1911 if (!fns || !is_overloaded_fn (fns))
1913 error ("%qD is not a template function", dname);
1914 fns = error_mark_node;
1918 tree fn = OVL_CURRENT (fns);
1919 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
1920 CP_DECL_CONTEXT (fn)))
1921 error ("%qD is not declared in %qD",
1922 decl, current_namespace);
1926 declarator = lookup_template_function (fns, NULL_TREE);
1929 if (declarator == error_mark_node)
1930 return error_mark_node;
1932 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1934 if (!explicit_instantiation)
1935 /* A specialization in class scope. This is invalid,
1936 but the error will already have been flagged by
1937 check_specialization_scope. */
1938 return error_mark_node;
1941 /* It's not valid to write an explicit instantiation in
1944 class C { template void f(); }
1946 This case is caught by the parser. However, on
1949 template class C { void f(); };
1951 (which is invalid) we can get here. The error will be
1958 else if (ctype != NULL_TREE
1959 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1962 /* Find the list of functions in ctype that have the same
1963 name as the declared function. */
1964 tree name = TREE_OPERAND (declarator, 0);
1965 tree fns = NULL_TREE;
1968 if (constructor_name_p (name, ctype))
1970 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1972 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1973 : !CLASSTYPE_DESTRUCTORS (ctype))
1975 /* From [temp.expl.spec]:
1977 If such an explicit specialization for the member
1978 of a class template names an implicitly-declared
1979 special member function (clause _special_), the
1980 program is ill-formed.
1982 Similar language is found in [temp.explicit]. */
1983 error ("specialization of implicitly-declared special member function");
1984 return error_mark_node;
1987 name = is_constructor ? ctor_identifier : dtor_identifier;
1990 if (!DECL_CONV_FN_P (decl))
1992 idx = lookup_fnfields_1 (ctype, name);
1994 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1998 VEC(tree,gc) *methods;
2001 /* For a type-conversion operator, we cannot do a
2002 name-based lookup. We might be looking for `operator
2003 int' which will be a specialization of `operator T'.
2004 So, we find *all* the conversion operators, and then
2005 select from them. */
2008 methods = CLASSTYPE_METHOD_VEC (ctype);
2010 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2011 VEC_iterate (tree, methods, idx, ovl);
2014 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2015 /* There are no more conversion functions. */
2018 /* Glue all these conversion functions together
2019 with those we already have. */
2020 for (; ovl; ovl = OVL_NEXT (ovl))
2021 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2025 if (fns == NULL_TREE)
2027 error ("no member function %qD declared in %qT", name, ctype);
2028 return error_mark_node;
2031 TREE_OPERAND (declarator, 0) = fns;
2034 /* Figure out what exactly is being specialized at this point.
2035 Note that for an explicit instantiation, even one for a
2036 member function, we cannot tell apriori whether the
2037 instantiation is for a member template, or just a member
2038 function of a template class. Even if a member template is
2039 being instantiated, the member template arguments may be
2040 elided if they can be deduced from the rest of the
2042 tmpl = determine_specialization (declarator, decl,
2044 member_specialization,
2047 if (!tmpl || tmpl == error_mark_node)
2048 /* We couldn't figure out what this declaration was
2050 return error_mark_node;
2053 tree gen_tmpl = most_general_template (tmpl);
2055 if (explicit_instantiation)
2057 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2058 is done by do_decl_instantiation later. */
2060 int arg_depth = TMPL_ARGS_DEPTH (targs);
2061 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2063 if (arg_depth > parm_depth)
2065 /* If TMPL is not the most general template (for
2066 example, if TMPL is a friend template that is
2067 injected into namespace scope), then there will
2068 be too many levels of TARGS. Remove some of them
2073 new_targs = make_tree_vec (parm_depth);
2074 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2075 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2076 = TREE_VEC_ELT (targs, i);
2080 return instantiate_template (tmpl, targs, tf_error);
2083 /* If we thought that the DECL was a member function, but it
2084 turns out to be specializing a static member function,
2085 make DECL a static member function as well. */
2086 if (DECL_STATIC_FUNCTION_P (tmpl)
2087 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2088 revert_static_member_fn (decl);
2090 /* If this is a specialization of a member template of a
2091 template class. In we want to return the TEMPLATE_DECL,
2092 not the specialization of it. */
2093 if (tsk == tsk_template)
2095 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2096 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2099 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2100 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2101 = DECL_SOURCE_LOCATION (decl);
2102 /* We want to use the argument list specified in the
2103 definition, not in the original declaration. */
2104 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2105 = DECL_ARGUMENTS (decl);
2110 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2111 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2113 /* Inherit default function arguments from the template
2114 DECL is specializing. */
2115 copy_default_args_to_explicit_spec (decl);
2117 /* This specialization has the same protection as the
2118 template it specializes. */
2119 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2120 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2121 /* The specialization has the same visibility as the
2122 template it specializes. */
2123 if (DECL_VISIBILITY_SPECIFIED (gen_tmpl))
2125 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2126 DECL_VISIBILITY (decl) = DECL_VISIBILITY (gen_tmpl);
2128 /* If DECL is a friend declaration, declared using an
2129 unqualified name, the namespace associated with DECL may
2130 have been set incorrectly. For example, in:
2132 template <typename T> void f(T);
2134 struct S { friend void f<int>(int); }
2137 we will have set the DECL_CONTEXT for the friend
2138 declaration to N, rather than to the global namespace. */
2139 if (DECL_NAMESPACE_SCOPE_P (decl))
2140 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2142 if (is_friend && !have_def)
2143 /* This is not really a declaration of a specialization.
2144 It's just the name of an instantiation. But, it's not
2145 a request for an instantiation, either. */
2146 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2147 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2148 /* This is indeed a specialization. In case of constructors
2149 and destructors, we need in-charge and not-in-charge
2150 versions in V3 ABI. */
2151 clone_function_decl (decl, /*update_method_vec_p=*/0);
2153 /* Register this specialization so that we can find it
2155 decl = register_specialization (decl, gen_tmpl, targs, is_friend);
2162 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2163 parameters. These are represented in the same format used for
2164 DECL_TEMPLATE_PARMS. */
2167 comp_template_parms (tree parms1, tree parms2)
2172 if (parms1 == parms2)
2175 for (p1 = parms1, p2 = parms2;
2176 p1 != NULL_TREE && p2 != NULL_TREE;
2177 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2179 tree t1 = TREE_VALUE (p1);
2180 tree t2 = TREE_VALUE (p2);
2183 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2184 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2186 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2189 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2191 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2192 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2194 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2197 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2199 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2204 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2205 /* One set of parameters has more parameters lists than the
2212 /* Complain if DECL shadows a template parameter.
2214 [temp.local]: A template-parameter shall not be redeclared within its
2215 scope (including nested scopes). */
2218 check_template_shadow (tree decl)
2222 /* If we're not in a template, we can't possibly shadow a template
2224 if (!current_template_parms)
2227 /* Figure out what we're shadowing. */
2228 if (TREE_CODE (decl) == OVERLOAD)
2229 decl = OVL_CURRENT (decl);
2230 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2232 /* If there's no previous binding for this name, we're not shadowing
2233 anything, let alone a template parameter. */
2237 /* If we're not shadowing a template parameter, we're done. Note
2238 that OLDDECL might be an OVERLOAD (or perhaps even an
2239 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2241 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2244 /* We check for decl != olddecl to avoid bogus errors for using a
2245 name inside a class. We check TPFI to avoid duplicate errors for
2246 inline member templates. */
2248 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2251 error ("declaration of %q+#D", decl);
2252 error (" shadows template parm %q+#D", olddecl);
2255 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2256 ORIG_LEVEL, DECL, and TYPE. */
2259 build_template_parm_index (int index,
2265 tree t = make_node (TEMPLATE_PARM_INDEX);
2266 TEMPLATE_PARM_IDX (t) = index;
2267 TEMPLATE_PARM_LEVEL (t) = level;
2268 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2269 TEMPLATE_PARM_DECL (t) = decl;
2270 TREE_TYPE (t) = type;
2271 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2272 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2273 TREE_READONLY (t) = TREE_READONLY (decl);
2278 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2279 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2280 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2281 new one is created. */
2284 reduce_template_parm_level (tree index, tree type, int levels)
2286 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2287 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2288 != TEMPLATE_PARM_LEVEL (index) - levels))
2290 tree orig_decl = TEMPLATE_PARM_DECL (index);
2293 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2294 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2295 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2296 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2297 DECL_ARTIFICIAL (decl) = 1;
2298 SET_DECL_TEMPLATE_PARM_P (decl);
2300 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2301 TEMPLATE_PARM_LEVEL (index) - levels,
2302 TEMPLATE_PARM_ORIG_LEVEL (index),
2304 TEMPLATE_PARM_DESCENDANTS (index) = t;
2306 /* Template template parameters need this. */
2307 if (TREE_CODE (decl) != CONST_DECL)
2308 DECL_TEMPLATE_PARMS (decl)
2309 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2312 return TEMPLATE_PARM_DESCENDANTS (index);
2315 /* Process information from new template parameter PARM and append it to the
2316 LIST being built. This new parameter is a non-type parameter iff
2317 IS_NON_TYPE is true. */
2320 process_template_parm (tree list, tree parm, bool is_non_type)
2326 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2327 defval = TREE_PURPOSE (parm);
2331 tree p = TREE_VALUE (tree_last (list));
2333 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2334 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2336 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2344 parm = TREE_VALUE (parm);
2346 SET_DECL_TEMPLATE_PARM_P (parm);
2348 if (TREE_TYPE (parm) == error_mark_node)
2349 TREE_TYPE (parm) = void_type_node;
2354 The top-level cv-qualifiers on the template-parameter are
2355 ignored when determining its type. */
2356 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2357 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2358 TREE_TYPE (parm) = void_type_node;
2361 /* A template parameter is not modifiable. */
2362 TREE_CONSTANT (parm) = 1;
2363 TREE_INVARIANT (parm) = 1;
2364 TREE_READONLY (parm) = 1;
2365 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2366 TREE_CONSTANT (decl) = 1;
2367 TREE_INVARIANT (decl) = 1;
2368 TREE_READONLY (decl) = 1;
2369 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2370 = build_template_parm_index (idx, processing_template_decl,
2371 processing_template_decl,
2372 decl, TREE_TYPE (parm));
2377 parm = TREE_VALUE (TREE_VALUE (parm));
2379 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2381 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2382 /* This is for distinguishing between real templates and template
2383 template parameters */
2384 TREE_TYPE (parm) = t;
2385 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2390 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2391 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2392 decl = build_decl (TYPE_DECL, parm, t);
2395 TYPE_NAME (t) = decl;
2396 TYPE_STUB_DECL (t) = decl;
2398 TEMPLATE_TYPE_PARM_INDEX (t)
2399 = build_template_parm_index (idx, processing_template_decl,
2400 processing_template_decl,
2401 decl, TREE_TYPE (parm));
2403 DECL_ARTIFICIAL (decl) = 1;
2404 SET_DECL_TEMPLATE_PARM_P (decl);
2406 parm = build_tree_list (defval, parm);
2407 return chainon (list, parm);
2410 /* The end of a template parameter list has been reached. Process the
2411 tree list into a parameter vector, converting each parameter into a more
2412 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2416 end_template_parm_list (tree parms)
2420 tree saved_parmlist = make_tree_vec (list_length (parms));
2422 current_template_parms
2423 = tree_cons (size_int (processing_template_decl),
2424 saved_parmlist, current_template_parms);
2426 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2428 next = TREE_CHAIN (parm);
2429 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2430 TREE_CHAIN (parm) = NULL_TREE;
2433 --processing_template_parmlist;
2435 return saved_parmlist;
2438 /* end_template_decl is called after a template declaration is seen. */
2441 end_template_decl (void)
2443 reset_specialization ();
2445 if (! processing_template_decl)
2448 /* This matches the pushlevel in begin_template_parm_list. */
2451 --processing_template_decl;
2452 current_template_parms = TREE_CHAIN (current_template_parms);
2455 /* Given a template argument vector containing the template PARMS.
2456 The innermost PARMS are given first. */
2459 current_template_args (void)
2462 tree args = NULL_TREE;
2463 int length = TMPL_PARMS_DEPTH (current_template_parms);
2466 /* If there is only one level of template parameters, we do not
2467 create a TREE_VEC of TREE_VECs. Instead, we return a single
2468 TREE_VEC containing the arguments. */
2470 args = make_tree_vec (length);
2472 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2474 tree a = copy_node (TREE_VALUE (header));
2477 TREE_TYPE (a) = NULL_TREE;
2478 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2480 tree t = TREE_VEC_ELT (a, i);
2482 /* T will be a list if we are called from within a
2483 begin/end_template_parm_list pair, but a vector directly
2484 if within a begin/end_member_template_processing pair. */
2485 if (TREE_CODE (t) == TREE_LIST)
2489 if (TREE_CODE (t) == TYPE_DECL
2490 || TREE_CODE (t) == TEMPLATE_DECL)
2493 t = DECL_INITIAL (t);
2494 TREE_VEC_ELT (a, i) = t;
2499 TREE_VEC_ELT (args, --l) = a;
2507 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2508 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2509 a member template. Used by push_template_decl below. */
2512 build_template_decl (tree decl, tree parms, bool member_template_p)
2514 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2515 DECL_TEMPLATE_PARMS (tmpl) = parms;
2516 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2517 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2518 if (DECL_LANG_SPECIFIC (decl))
2520 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2521 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2522 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2523 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2524 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2525 if (DECL_OVERLOADED_OPERATOR_P (decl))
2526 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2527 DECL_OVERLOADED_OPERATOR_P (decl));
2533 struct template_parm_data
2535 /* The level of the template parameters we are currently
2539 /* The index of the specialization argument we are currently
2543 /* An array whose size is the number of template parameters. The
2544 elements are nonzero if the parameter has been used in any one
2545 of the arguments processed so far. */
2548 /* An array whose size is the number of template arguments. The
2549 elements are nonzero if the argument makes use of template
2550 parameters of this level. */
2551 int* arg_uses_template_parms;
2554 /* Subroutine of push_template_decl used to see if each template
2555 parameter in a partial specialization is used in the explicit
2556 argument list. If T is of the LEVEL given in DATA (which is
2557 treated as a template_parm_data*), then DATA->PARMS is marked
2561 mark_template_parm (tree t, void* data)
2565 struct template_parm_data* tpd = (struct template_parm_data*) data;
2567 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2569 level = TEMPLATE_PARM_LEVEL (t);
2570 idx = TEMPLATE_PARM_IDX (t);
2574 level = TEMPLATE_TYPE_LEVEL (t);
2575 idx = TEMPLATE_TYPE_IDX (t);
2578 if (level == tpd->level)
2580 tpd->parms[idx] = 1;
2581 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2584 /* Return zero so that for_each_template_parm will continue the
2585 traversal of the tree; we want to mark *every* template parm. */
2589 /* Process the partial specialization DECL. */
2592 process_partial_specialization (tree decl)
2594 tree type = TREE_TYPE (decl);
2595 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2596 tree specargs = CLASSTYPE_TI_ARGS (type);
2597 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2598 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2599 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2600 int nargs = TREE_VEC_LENGTH (inner_args);
2601 int ntparms = TREE_VEC_LENGTH (inner_parms);
2603 int did_error_intro = 0;
2604 struct template_parm_data tpd;
2605 struct template_parm_data tpd2;
2607 /* We check that each of the template parameters given in the
2608 partial specialization is used in the argument list to the
2609 specialization. For example:
2611 template <class T> struct S;
2612 template <class T> struct S<T*>;
2614 The second declaration is OK because `T*' uses the template
2615 parameter T, whereas
2617 template <class T> struct S<int>;
2619 is no good. Even trickier is:
2630 The S2<T> declaration is actually invalid; it is a
2631 full-specialization. Of course,
2634 struct S2<T (*)(U)>;
2636 or some such would have been OK. */
2637 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2638 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
2639 memset (tpd.parms, 0, sizeof (int) * ntparms);
2641 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
2642 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2643 for (i = 0; i < nargs; ++i)
2645 tpd.current_arg = i;
2646 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2647 &mark_template_parm,
2651 for (i = 0; i < ntparms; ++i)
2652 if (tpd.parms[i] == 0)
2654 /* One of the template parms was not used in the
2656 if (!did_error_intro)
2658 error ("template parameters not used in partial specialization:");
2659 did_error_intro = 1;
2662 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2665 /* [temp.class.spec]
2667 The argument list of the specialization shall not be identical to
2668 the implicit argument list of the primary template. */
2669 if (comp_template_args
2671 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2673 error ("partial specialization %qT does not specialize any template arguments", type);
2675 /* [temp.class.spec]
2677 A partially specialized non-type argument expression shall not
2678 involve template parameters of the partial specialization except
2679 when the argument expression is a simple identifier.
2681 The type of a template parameter corresponding to a specialized
2682 non-type argument shall not be dependent on a parameter of the
2684 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2686 for (i = 0; i < nargs; ++i)
2688 tree arg = TREE_VEC_ELT (inner_args, i);
2689 if (/* These first two lines are the `non-type' bit. */
2691 && TREE_CODE (arg) != TEMPLATE_DECL
2692 /* This next line is the `argument expression is not just a
2693 simple identifier' condition and also the `specialized
2694 non-type argument' bit. */
2695 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2697 if (tpd.arg_uses_template_parms[i])
2698 error ("template argument %qE involves template parameter(s)", arg);
2701 /* Look at the corresponding template parameter,
2702 marking which template parameters its type depends
2705 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2710 /* We haven't yet initialized TPD2. Do so now. */
2711 tpd2.arg_uses_template_parms
2712 = (int *) alloca (sizeof (int) * nargs);
2713 /* The number of parameters here is the number in the
2714 main template, which, as checked in the assertion
2716 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
2718 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2721 /* Mark the template parameters. But this time, we're
2722 looking for the template parameters of the main
2723 template, not in the specialization. */
2724 tpd2.current_arg = i;
2725 tpd2.arg_uses_template_parms[i] = 0;
2726 memset (tpd2.parms, 0, sizeof (int) * nargs);
2727 for_each_template_parm (type,
2728 &mark_template_parm,
2732 if (tpd2.arg_uses_template_parms [i])
2734 /* The type depended on some template parameters.
2735 If they are fully specialized in the
2736 specialization, that's OK. */
2738 for (j = 0; j < nargs; ++j)
2739 if (tpd2.parms[j] != 0
2740 && tpd.arg_uses_template_parms [j])
2742 error ("type %qT of template argument %qE depends "
2743 "on template parameter(s)",
2753 if (retrieve_specialization (maintmpl, specargs,
2754 /*class_specializations_p=*/true))
2755 /* We've already got this specialization. */
2758 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2759 = tree_cons (specargs, inner_parms,
2760 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2761 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2765 /* Check that a template declaration's use of default arguments is not
2766 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2767 nonzero if DECL is the thing declared by a primary template.
2768 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2771 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2774 int last_level_to_check;
2779 A default template-argument shall not be specified in a
2780 function template declaration or a function template definition, nor
2781 in the template-parameter-list of the definition of a member of a
2784 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2785 /* You can't have a function template declaration in a local
2786 scope, nor you can you define a member of a class template in a
2790 if (current_class_type
2791 && !TYPE_BEING_DEFINED (current_class_type)
2792 && DECL_LANG_SPECIFIC (decl)
2793 /* If this is either a friend defined in the scope of the class
2794 or a member function. */
2795 && (DECL_FUNCTION_MEMBER_P (decl)
2796 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2797 : DECL_FRIEND_CONTEXT (decl)
2798 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2800 /* And, if it was a member function, it really was defined in
2801 the scope of the class. */
2802 && (!DECL_FUNCTION_MEMBER_P (decl)
2803 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2804 /* We already checked these parameters when the template was
2805 declared, so there's no need to do it again now. This function
2806 was defined in class scope, but we're processing it's body now
2807 that the class is complete. */
2812 If a template-parameter has a default template-argument, all
2813 subsequent template-parameters shall have a default
2814 template-argument supplied. */
2815 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2817 tree inner_parms = TREE_VALUE (parm_level);
2818 int ntparms = TREE_VEC_LENGTH (inner_parms);
2819 int seen_def_arg_p = 0;
2822 for (i = 0; i < ntparms; ++i)
2824 tree parm = TREE_VEC_ELT (inner_parms, i);
2825 if (TREE_PURPOSE (parm))
2827 else if (seen_def_arg_p)
2829 error ("no default argument for %qD", TREE_VALUE (parm));
2830 /* For better subsequent error-recovery, we indicate that
2831 there should have been a default argument. */
2832 TREE_PURPOSE (parm) = error_mark_node;
2837 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2838 /* For an ordinary class template, default template arguments are
2839 allowed at the innermost level, e.g.:
2840 template <class T = int>
2842 but, in a partial specialization, they're not allowed even
2843 there, as we have in [temp.class.spec]:
2845 The template parameter list of a specialization shall not
2846 contain default template argument values.
2848 So, for a partial specialization, or for a function template,
2849 we look at all of them. */
2852 /* But, for a primary class template that is not a partial
2853 specialization we look at all template parameters except the
2855 parms = TREE_CHAIN (parms);
2857 /* Figure out what error message to issue. */
2858 if (TREE_CODE (decl) == FUNCTION_DECL)
2859 msg = "default template arguments may not be used in function templates";
2860 else if (is_partial)
2861 msg = "default template arguments may not be used in partial specializations";
2863 msg = "default argument for template parameter for class enclosing %qD";
2865 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2866 /* If we're inside a class definition, there's no need to
2867 examine the parameters to the class itself. On the one
2868 hand, they will be checked when the class is defined, and,
2869 on the other, default arguments are valid in things like:
2870 template <class T = double>
2871 struct S { template <class U> void f(U); };
2872 Here the default argument for `S' has no bearing on the
2873 declaration of `f'. */
2874 last_level_to_check = template_class_depth (current_class_type) + 1;
2876 /* Check everything. */
2877 last_level_to_check = 0;
2879 for (parm_level = parms;
2880 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2881 parm_level = TREE_CHAIN (parm_level))
2883 tree inner_parms = TREE_VALUE (parm_level);
2887 ntparms = TREE_VEC_LENGTH (inner_parms);
2888 for (i = 0; i < ntparms; ++i)
2889 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2897 /* Clear out the default argument so that we are not
2899 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2902 /* At this point, if we're still interested in issuing messages,
2903 they must apply to classes surrounding the object declared. */
2905 msg = "default argument for template parameter for class enclosing %qD";
2909 /* Worker for push_template_decl_real, called via
2910 for_each_template_parm. DATA is really an int, indicating the
2911 level of the parameters we are interested in. If T is a template
2912 parameter of that level, return nonzero. */
2915 template_parm_this_level_p (tree t, void* data)
2917 int this_level = *(int *)data;
2920 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2921 level = TEMPLATE_PARM_LEVEL (t);
2923 level = TEMPLATE_TYPE_LEVEL (t);
2924 return level == this_level;
2927 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2928 parameters given by current_template_args, or reuses a
2929 previously existing one, if appropriate. Returns the DECL, or an
2930 equivalent one, if it is replaced via a call to duplicate_decls.
2932 If IS_FRIEND is true, DECL is a friend declaration. */
2935 push_template_decl_real (tree decl, bool is_friend)
2943 int new_template_p = 0;
2944 /* True if the template is a member template, in the sense of
2946 bool member_template_p = false;
2948 if (decl == error_mark_node)
2951 /* See if this is a partial specialization. */
2952 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2953 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2954 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2956 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
2960 /* For a friend, we want the context of the friend function, not
2961 the type of which it is a friend. */
2962 ctx = DECL_CONTEXT (decl);
2963 else if (CP_DECL_CONTEXT (decl)
2964 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2965 /* In the case of a virtual function, we want the class in which
2967 ctx = CP_DECL_CONTEXT (decl);
2969 /* Otherwise, if we're currently defining some class, the DECL
2970 is assumed to be a member of the class. */
2971 ctx = current_scope ();
2973 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2976 if (!DECL_CONTEXT (decl))
2977 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2979 /* See if this is a primary template. */
2980 primary = template_parm_scope_p ();
2984 if (DECL_CLASS_SCOPE_P (decl))
2985 member_template_p = true;
2986 if (TREE_CODE (decl) == TYPE_DECL
2987 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2988 error ("template class without a name");
2989 else if (TREE_CODE (decl) == FUNCTION_DECL)
2991 if (DECL_DESTRUCTOR_P (decl))
2995 A destructor shall not be a member template. */
2996 error ("destructor %qD declared as member template", decl);
2997 return error_mark_node;
2999 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
3000 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
3001 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
3002 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
3003 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
3004 == void_list_node)))
3006 /* [basic.stc.dynamic.allocation]
3008 An allocation function can be a function
3009 template. ... Template allocation functions shall
3010 have two or more parameters. */
3011 error ("invalid template declaration of %qD", decl);
3012 return error_mark_node;
3015 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3016 && CLASS_TYPE_P (TREE_TYPE (decl)))
3020 error ("template declaration of %q#D", decl);
3021 return error_mark_node;
3025 /* Check to see that the rules regarding the use of default
3026 arguments are not being violated. */
3027 check_default_tmpl_args (decl, current_template_parms,
3028 primary, is_partial);
3031 return process_partial_specialization (decl);
3033 args = current_template_args ();
3036 || TREE_CODE (ctx) == FUNCTION_DECL
3037 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3038 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3040 if (DECL_LANG_SPECIFIC (decl)
3041 && DECL_TEMPLATE_INFO (decl)
3042 && DECL_TI_TEMPLATE (decl))
3043 tmpl = DECL_TI_TEMPLATE (decl);
3044 /* If DECL is a TYPE_DECL for a class-template, then there won't
3045 be DECL_LANG_SPECIFIC. The information equivalent to
3046 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3047 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3048 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3049 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3051 /* Since a template declaration already existed for this
3052 class-type, we must be redeclaring it here. Make sure
3053 that the redeclaration is valid. */
3054 redeclare_class_template (TREE_TYPE (decl),
3055 current_template_parms);
3056 /* We don't need to create a new TEMPLATE_DECL; just use the
3057 one we already had. */
3058 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3062 tmpl = build_template_decl (decl, current_template_parms,
3066 if (DECL_LANG_SPECIFIC (decl)
3067 && DECL_TEMPLATE_SPECIALIZATION (decl))
3069 /* A specialization of a member template of a template
3071 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3072 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3073 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3079 tree a, t, current, parms;
3082 if (TREE_CODE (decl) == TYPE_DECL)
3084 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3085 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3086 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3087 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3088 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3091 error ("%qD does not declare a template type", decl);
3095 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3097 error ("template definition of non-template %q#D", decl);
3101 tmpl = DECL_TI_TEMPLATE (decl);
3103 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3104 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3105 && DECL_TEMPLATE_SPECIALIZATION (decl)
3106 && DECL_MEMBER_TEMPLATE_P (tmpl))
3110 /* The declaration is a specialization of a member
3111 template, declared outside the class. Therefore, the
3112 innermost template arguments will be NULL, so we
3113 replace them with the arguments determined by the
3114 earlier call to check_explicit_specialization. */
3115 args = DECL_TI_ARGS (decl);
3118 = build_template_decl (decl, current_template_parms,
3120 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3121 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3122 DECL_TI_TEMPLATE (decl) = new_tmpl;
3123 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3124 DECL_TEMPLATE_INFO (new_tmpl)
3125 = tree_cons (tmpl, args, NULL_TREE);
3127 register_specialization (new_tmpl,
3128 most_general_template (tmpl),
3134 /* Make sure the template headers we got make sense. */
3136 parms = DECL_TEMPLATE_PARMS (tmpl);
3137 i = TMPL_PARMS_DEPTH (parms);
3138 if (TMPL_ARGS_DEPTH (args) != i)
3140 error ("expected %d levels of template parms for %q#D, got %d",
3141 i, decl, TMPL_ARGS_DEPTH (args));
3144 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3146 a = TMPL_ARGS_LEVEL (args, i);
3147 t = INNERMOST_TEMPLATE_PARMS (parms);
3149 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3151 if (current == decl)
3152 error ("got %d template parameters for %q#D",
3153 TREE_VEC_LENGTH (a), decl);
3155 error ("got %d template parameters for %q#T",
3156 TREE_VEC_LENGTH (a), current);
3157 error (" but %d required", TREE_VEC_LENGTH (t));
3158 return error_mark_node;
3161 /* Perhaps we should also check that the parms are used in the
3162 appropriate qualifying scopes in the declarator? */
3164 if (current == decl)
3167 current = TYPE_CONTEXT (current);
3171 DECL_TEMPLATE_RESULT (tmpl) = decl;
3172 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3174 /* Push template declarations for global functions and types. Note
3175 that we do not try to push a global template friend declared in a
3176 template class; such a thing may well depend on the template
3177 parameters of the class. */
3178 if (new_template_p && !ctx
3179 && !(is_friend && template_class_depth (current_class_type) > 0))
3181 tmpl = pushdecl_namespace_level (tmpl, is_friend);
3182 if (tmpl == error_mark_node)
3183 return error_mark_node;
3185 /* Hide template friend classes that haven't been declared yet. */
3186 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
3188 DECL_ANTICIPATED (tmpl) = 1;
3189 DECL_FRIEND_P (tmpl) = 1;
3195 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3196 if (DECL_CONV_FN_P (tmpl))
3198 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3200 /* It is a conversion operator. See if the type converted to
3201 depends on innermost template operands. */
3203 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3205 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3209 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3210 back to its most general template. If TMPL is a specialization,
3211 ARGS may only have the innermost set of arguments. Add the missing
3212 argument levels if necessary. */
3213 if (DECL_TEMPLATE_INFO (tmpl))
3214 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3216 info = tree_cons (tmpl, args, NULL_TREE);
3218 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3220 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3221 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3222 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3223 /* Don't change the name if we've already set it up. */
3224 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3225 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3227 else if (DECL_LANG_SPECIFIC (decl))
3228 DECL_TEMPLATE_INFO (decl) = info;
3230 return DECL_TEMPLATE_RESULT (tmpl);
3234 push_template_decl (tree decl)
3236 return push_template_decl_real (decl, false);
3239 /* Called when a class template TYPE is redeclared with the indicated
3240 template PARMS, e.g.:
3242 template <class T> struct S;
3243 template <class T> struct S {}; */
3246 redeclare_class_template (tree type, tree parms)
3252 if (!TYPE_TEMPLATE_INFO (type))
3254 error ("%qT is not a template type", type);
3258 tmpl = TYPE_TI_TEMPLATE (type);
3259 if (!PRIMARY_TEMPLATE_P (tmpl))
3260 /* The type is nested in some template class. Nothing to worry
3261 about here; there are no new template parameters for the nested
3267 error ("template specifiers not specified in declaration of %qD",
3272 parms = INNERMOST_TEMPLATE_PARMS (parms);
3273 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3275 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3277 error ("previous declaration %q+D", tmpl);
3278 error ("used %d template parameter(s) instead of %d",
3279 TREE_VEC_LENGTH (tmpl_parms),
3280 TREE_VEC_LENGTH (parms));
3284 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3286 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3287 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3288 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3289 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3291 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3293 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3294 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3295 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3297 error ("template parameter %q+#D", tmpl_parm);
3298 error ("redeclared here as %q#D", parm);
3302 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3304 /* We have in [temp.param]:
3306 A template-parameter may not be given default arguments
3307 by two different declarations in the same scope. */
3308 error ("redefinition of default argument for %q#D", parm);
3309 error ("%J original definition appeared here", tmpl_parm);
3313 if (parm_default != NULL_TREE)
3314 /* Update the previous template parameters (which are the ones
3315 that will really count) with the new default value. */
3316 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3317 else if (tmpl_default != NULL_TREE)
3318 /* Update the new parameters, too; they'll be used as the
3319 parameters for any members. */
3320 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3324 /* Simplify EXPR if it is a non-dependent expression. Returns the
3325 (possibly simplified) expression. */
3328 fold_non_dependent_expr (tree expr)
3330 /* If we're in a template, but EXPR isn't value dependent, simplify
3331 it. We're supposed to treat:
3333 template <typename T> void f(T[1 + 1]);
3334 template <typename T> void f(T[2]);
3336 as two declarations of the same function, for example. */
3337 if (processing_template_decl
3338 && !type_dependent_expression_p (expr)
3339 && !value_dependent_expression_p (expr))
3341 HOST_WIDE_INT saved_processing_template_decl;
3343 saved_processing_template_decl = processing_template_decl;
3344 processing_template_decl = 0;
3345 expr = tsubst_copy_and_build (expr,
3348 /*in_decl=*/NULL_TREE,
3349 /*function_p=*/false);
3350 processing_template_decl = saved_processing_template_decl;
3355 /* EXPR is an expression which is used in a constant-expression context.
3356 For instance, it could be a VAR_DECL with a constant initializer.
3357 Extract the innest constant expression.
3359 This is basically a more powerful version of
3360 integral_constant_value, which can be used also in templates where
3361 initializers can maintain a syntactic rather than semantic form
3362 (even if they are non-dependent, for access-checking purposes). */
3365 fold_decl_constant_value (tree expr)
3367 tree const_expr = expr;
3370 expr = fold_non_dependent_expr (const_expr);
3371 const_expr = integral_constant_value (expr);
3373 while (expr != const_expr);
3378 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3379 must be a function or a pointer-to-function type, as specified
3380 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3381 and check that the resulting function has external linkage. */
3384 convert_nontype_argument_function (tree type, tree expr)
3389 fn = instantiate_type (type, fns, tf_none);
3390 if (fn == error_mark_node)
3391 return error_mark_node;
3394 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3395 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3397 /* [temp.arg.nontype]/1
3399 A template-argument for a non-type, non-template template-parameter
3402 -- the address of an object or function with external linkage. */
3403 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3405 error ("%qE is not a valid template argument for type %qT "
3406 "because function %qD has not external linkage",
3407 expr, type, fn_no_ptr);
3414 /* Attempt to convert the non-type template parameter EXPR to the
3415 indicated TYPE. If the conversion is successful, return the
3416 converted value. If the conversion is unsuccessful, return
3417 NULL_TREE if we issued an error message, or error_mark_node if we
3418 did not. We issue error messages for out-and-out bad template
3419 parameters, but not simply because the conversion failed, since we
3420 might be just trying to do argument deduction. Both TYPE and EXPR
3421 must be non-dependent.
3423 The conversion follows the special rules described in
3424 [temp.arg.nontype], and it is much more strict than an implicit
3427 This function is called twice for each template argument (see
3428 lookup_template_class for a more accurate description of this
3429 problem). This means that we need to handle expressions which
3430 are not valid in a C++ source, but can be created from the
3431 first call (for instance, casts to perform conversions). These
3432 hacks can go away after we fix the double coercion problem. */
3435 convert_nontype_argument (tree type, tree expr)
3439 /* Detect immediately string literals as invalid non-type argument.
3440 This special-case is not needed for correctness (we would easily
3441 catch this later), but only to provide better diagnostic for this
3442 common user mistake. As suggested by DR 100, we do not mention
3443 linkage issues in the diagnostic as this is not the point. */
3444 if (TREE_CODE (expr) == STRING_CST)
3446 error ("%qE is not a valid template argument for type %qT "
3447 "because string literals can never be used in this context",
3452 /* If we are in a template, EXPR may be non-dependent, but still
3453 have a syntactic, rather than semantic, form. For example, EXPR
3454 might be a SCOPE_REF, rather than the VAR_DECL to which the
3455 SCOPE_REF refers. Preserving the qualifying scope is necessary
3456 so that access checking can be performed when the template is
3457 instantiated -- but here we need the resolved form so that we can
3458 convert the argument. */
3459 expr = fold_non_dependent_expr (expr);
3460 if (error_operand_p (expr))
3461 return error_mark_node;
3462 expr_type = TREE_TYPE (expr);
3464 /* HACK: Due to double coercion, we can get a
3465 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3466 which is the tree that we built on the first call (see
3467 below when coercing to reference to object or to reference to
3468 function). We just strip everything and get to the arg.
3469 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3471 if (TREE_CODE (expr) == NOP_EXPR)
3473 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3475 /* ??? Maybe we could use convert_from_reference here, but we
3476 would need to relax its constraints because the NOP_EXPR
3477 could actually change the type to something more cv-qualified,
3478 and this is not folded by convert_from_reference. */
3479 tree addr = TREE_OPERAND (expr, 0);
3480 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3481 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3482 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3483 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3484 (TREE_TYPE (expr_type),
3485 TREE_TYPE (TREE_TYPE (addr))));
3487 expr = TREE_OPERAND (addr, 0);
3488 expr_type = TREE_TYPE (expr);
3491 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3492 parameter is a pointer to object, through decay and
3493 qualification conversion. Let's strip everything. */
3494 else if (TYPE_PTROBV_P (type))
3497 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3498 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3499 /* Skip the ADDR_EXPR only if it is part of the decay for
3500 an array. Otherwise, it is part of the original argument
3501 in the source code. */
3502 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3503 expr = TREE_OPERAND (expr, 0);
3504 expr_type = TREE_TYPE (expr);
3508 /* [temp.arg.nontype]/5, bullet 1
3510 For a non-type template-parameter of integral or enumeration type,
3511 integral promotions (_conv.prom_) and integral conversions
3512 (_conv.integral_) are applied. */
3513 if (INTEGRAL_TYPE_P (type))
3515 if (!INTEGRAL_TYPE_P (expr_type))
3516 return error_mark_node;
3518 expr = fold_decl_constant_value (expr);
3519 /* Notice that there are constant expressions like '4 % 0' which
3520 do not fold into integer constants. */
3521 if (TREE_CODE (expr) != INTEGER_CST)
3523 error ("%qE is not a valid template argument for type %qT "
3524 "because it is a non-constant expression", expr, type);
3528 /* At this point, an implicit conversion does what we want,
3529 because we already know that the expression is of integral
3531 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3532 if (expr == error_mark_node)
3533 return error_mark_node;
3535 /* Conversion was allowed: fold it to a bare integer constant. */
3538 /* [temp.arg.nontype]/5, bullet 2
3540 For a non-type template-parameter of type pointer to object,
3541 qualification conversions (_conv.qual_) and the array-to-pointer
3542 conversion (_conv.array_) are applied. */
3543 else if (TYPE_PTROBV_P (type))
3545 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3547 A template-argument for a non-type, non-template template-parameter
3548 shall be one of: [...]
3550 -- the name of a non-type template-parameter;
3551 -- the address of an object or function with external linkage, [...]
3552 expressed as "& id-expression" where the & is optional if the name
3553 refers to a function or array, or if the corresponding
3554 template-parameter is a reference.
3556 Here, we do not care about functions, as they are invalid anyway
3557 for a parameter of type pointer-to-object. */
3558 bool constant_address_p =
3559 (TREE_CODE (expr) == ADDR_EXPR
3560 || TREE_CODE (expr_type) == ARRAY_TYPE
3561 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3563 expr = decay_conversion (expr);
3564 if (expr == error_mark_node)
3565 return error_mark_node;
3567 expr = perform_qualification_conversions (type, expr);
3568 if (expr == error_mark_node)
3569 return error_mark_node;
3571 if (!constant_address_p)
3573 error ("%qE is not a valid template argument for type %qT "
3574 "because it is not a constant pointer", expr, type);
3578 /* [temp.arg.nontype]/5, bullet 3
3580 For a non-type template-parameter of type reference to object, no
3581 conversions apply. The type referred to by the reference may be more
3582 cv-qualified than the (otherwise identical) type of the
3583 template-argument. The template-parameter is bound directly to the
3584 template-argument, which must be an lvalue. */
3585 else if (TYPE_REF_OBJ_P (type))
3587 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3589 return error_mark_node;
3591 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3593 error ("%qE is not a valid template argument for type %qT "
3594 "because of conflicts in cv-qualification", expr, type);
3598 if (!real_lvalue_p (expr))
3600 error ("%qE is not a valid template argument for type %qT "
3601 "because it is not a lvalue", expr, type);
3605 /* [temp.arg.nontype]/1
3607 A template-argument for a non-type, non-template template-parameter
3608 shall be one of: [...]
3610 -- the address of an object or function with external linkage. */
3611 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3613 error ("%qE is not a valid template argument for type %qT "
3614 "because object %qD has not external linkage",
3619 expr = build_nop (type, build_address (expr));
3621 /* [temp.arg.nontype]/5, bullet 4
3623 For a non-type template-parameter of type pointer to function, only
3624 the function-to-pointer conversion (_conv.func_) is applied. If the
3625 template-argument represents a set of overloaded functions (or a
3626 pointer to such), the matching function is selected from the set
3628 else if (TYPE_PTRFN_P (type))
3630 /* If the argument is a template-id, we might not have enough
3631 context information to decay the pointer. */
3632 if (!type_unknown_p (expr_type))
3634 expr = decay_conversion (expr);
3635 if (expr == error_mark_node)
3636 return error_mark_node;
3639 expr = convert_nontype_argument_function (type, expr);
3640 if (!expr || expr == error_mark_node)
3643 /* [temp.arg.nontype]/5, bullet 5
3645 For a non-type template-parameter of type reference to function, no
3646 conversions apply. If the template-argument represents a set of
3647 overloaded functions, the matching function is selected from the set
3649 else if (TYPE_REFFN_P (type))
3651 if (TREE_CODE (expr) == ADDR_EXPR)
3653 error ("%qE is not a valid template argument for type %qT "
3654 "because it is a pointer", expr, type);
3655 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3659 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3660 if (!expr || expr == error_mark_node)
3663 expr = build_nop (type, build_address (expr));
3665 /* [temp.arg.nontype]/5, bullet 6
3667 For a non-type template-parameter of type pointer to member function,
3668 no conversions apply. If the template-argument represents a set of
3669 overloaded member functions, the matching member function is selected
3670 from the set (_over.over_). */
3671 else if (TYPE_PTRMEMFUNC_P (type))
3673 expr = instantiate_type (type, expr, tf_none);
3674 if (expr == error_mark_node)
3675 return error_mark_node;
3677 /* There is no way to disable standard conversions in
3678 resolve_address_of_overloaded_function (called by
3679 instantiate_type). It is possible that the call succeeded by
3680 converting &B::I to &D::I (where B is a base of D), so we need
3681 to reject this conversion here.
3683 Actually, even if there was a way to disable standard conversions,
3684 it would still be better to reject them here so that we can
3685 provide a superior diagnostic. */
3686 if (!same_type_p (TREE_TYPE (expr), type))
3688 /* Make sure we are just one standard conversion off. */
3689 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3690 error ("%qE is not a valid template argument for type %qT "
3691 "because it is of type %qT", expr, type,
3693 inform ("standard conversions are not allowed in this context");
3697 /* [temp.arg.nontype]/5, bullet 7
3699 For a non-type template-parameter of type pointer to data member,
3700 qualification conversions (_conv.qual_) are applied. */
3701 else if (TYPE_PTRMEM_P (type))
3703 expr = perform_qualification_conversions (type, expr);
3704 if (expr == error_mark_node)
3707 /* A template non-type parameter must be one of the above. */
3711 /* Sanity check: did we actually convert the argument to the
3713 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3718 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3719 template template parameters. Both PARM_PARMS and ARG_PARMS are
3720 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3723 Consider the example:
3724 template <class T> class A;
3725 template<template <class U> class TT> class B;
3727 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
3728 the parameters to A, and OUTER_ARGS contains A. */
3731 coerce_template_template_parms (tree parm_parms,
3733 tsubst_flags_t complain,
3737 int nparms, nargs, i;
3740 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3741 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3743 nparms = TREE_VEC_LENGTH (parm_parms);
3744 nargs = TREE_VEC_LENGTH (arg_parms);
3746 if (nargs != nparms)
3749 for (i = 0; i < nparms; ++i)
3751 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3752 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3754 if (arg == NULL_TREE || arg == error_mark_node
3755 || parm == NULL_TREE || parm == error_mark_node)
3758 if (TREE_CODE (arg) != TREE_CODE (parm))
3761 switch (TREE_CODE (parm))
3767 /* We encounter instantiations of templates like
3768 template <template <template <class> class> class TT>
3771 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3772 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3774 if (!coerce_template_template_parms
3775 (parmparm, argparm, complain, in_decl, outer_args))
3781 /* The tsubst call is used to handle cases such as
3783 template <int> class C {};
3784 template <class T, template <T> class TT> class D {};
3787 i.e. the parameter list of TT depends on earlier parameters. */
3788 if (!dependent_type_p (TREE_TYPE (arg))
3790 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3802 /* Convert the indicated template ARG as necessary to match the
3803 indicated template PARM. Returns the converted ARG, or
3804 error_mark_node if the conversion was unsuccessful. Error and
3805 warning messages are issued under control of COMPLAIN. This
3806 conversion is for the Ith parameter in the parameter list. ARGS is
3807 the full set of template arguments deduced so far. */
3810 convert_template_argument (tree parm,
3813 tsubst_flags_t complain,
3819 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3821 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3823 if (TREE_CODE (arg) == TREE_LIST
3824 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3826 /* The template argument was the name of some
3827 member function. That's usually
3828 invalid, but static members are OK. In any
3829 case, grab the underlying fields/functions
3830 and issue an error later if required. */
3831 arg = TREE_VALUE (arg);
3832 TREE_TYPE (arg) = unknown_type_node;
3835 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3836 requires_type = (TREE_CODE (parm) == TYPE_DECL
3837 || requires_tmpl_type);
3839 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3840 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3841 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3842 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3845 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3846 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3847 arg = TYPE_STUB_DECL (arg);
3849 is_type = TYPE_P (arg) || is_tmpl_type;
3851 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3852 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3854 pedwarn ("to refer to a type member of a template parameter, "
3855 "use %<typename %E%>", arg);
3857 arg = make_typename_type (TREE_OPERAND (arg, 0),
3858 TREE_OPERAND (arg, 1),
3860 complain & tf_error);
3863 if (is_type != requires_type)
3867 if (complain & tf_error)
3869 error ("type/value mismatch at argument %d in template "
3870 "parameter list for %qD",
3873 error (" expected a constant of type %qT, got %qT",
3875 (is_tmpl_type ? DECL_NAME (arg) : arg));
3876 else if (requires_tmpl_type)
3877 error (" expected a class template, got %qE", arg);
3879 error (" expected a type, got %qE", arg);
3882 return error_mark_node;
3884 if (is_tmpl_type ^ requires_tmpl_type)
3886 if (in_decl && (complain & tf_error))
3888 error ("type/value mismatch at argument %d in template "
3889 "parameter list for %qD",
3892 error (" expected a type, got %qT", DECL_NAME (arg));
3894 error (" expected a class template, got %qT", arg);
3896 return error_mark_node;
3901 if (requires_tmpl_type)
3903 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3904 /* The number of argument required is not known yet.
3905 Just accept it for now. */
3906 val = TREE_TYPE (arg);
3909 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3910 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3912 if (coerce_template_template_parms (parmparm, argparm,
3918 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3920 if (val != error_mark_node
3921 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3922 val = TREE_TYPE (val);
3926 if (in_decl && (complain & tf_error))
3928 error ("type/value mismatch at argument %d in "
3929 "template parameter list for %qD",
3931 error (" expected a template of type %qD, got %qD",
3935 val = error_mark_node;
3941 /* We only form one instance of each template specialization.
3942 Therefore, if we use a non-canonical variant (i.e., a
3943 typedef), any future messages referring to the type will use
3944 the typedef, which is confusing if those future uses do not
3945 themselves also use the typedef. */
3947 val = canonical_type_variant (val);
3951 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3953 if (invalid_nontype_parm_type_p (t, complain))
3954 return error_mark_node;
3956 if (!uses_template_parms (arg) && !uses_template_parms (t))
3957 /* We used to call digest_init here. However, digest_init
3958 will report errors, which we don't want when complain
3959 is zero. More importantly, digest_init will try too
3960 hard to convert things: for example, `0' should not be
3961 converted to pointer type at this point according to
3962 the standard. Accepting this is not merely an
3963 extension, since deciding whether or not these
3964 conversions can occur is part of determining which
3965 function template to call, or whether a given explicit
3966 argument specification is valid. */
3967 val = convert_nontype_argument (t, arg);
3971 if (val == NULL_TREE)
3972 val = error_mark_node;
3973 else if (val == error_mark_node && (complain & tf_error))
3974 error ("could not convert template argument %qE to %qT", arg, t);
3980 /* Convert all template arguments to their appropriate types, and
3981 return a vector containing the innermost resulting template
3982 arguments. If any error occurs, return error_mark_node. Error and
3983 warning messages are issued under control of COMPLAIN.
3985 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
3986 for arguments not specified in ARGS. Otherwise, if
3987 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
3988 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
3989 USE_DEFAULT_ARGS is false, then all arguments must be specified in
3993 coerce_template_parms (tree parms,
3996 tsubst_flags_t complain,
3997 bool require_all_args,
3998 bool use_default_args)
4000 int nparms, nargs, i, lost = 0;
4003 tree new_inner_args;
4005 inner_args = INNERMOST_TEMPLATE_ARGS (args);
4006 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
4007 nparms = TREE_VEC_LENGTH (parms);
4012 && (!use_default_args
4013 || !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)))))
4015 if (complain & tf_error)
4017 error ("wrong number of template arguments (%d, should be %d)",
4021 error ("provided for %q+D", in_decl);
4024 return error_mark_node;
4027 new_inner_args = make_tree_vec (nparms);
4028 new_args = add_outermost_template_args (args, new_inner_args);
4029 for (i = 0; i < nparms; i++)
4034 /* Get the Ith template parameter. */
4035 parm = TREE_VEC_ELT (parms, i);
4037 /* Calculate the Ith argument. */
4039 arg = TREE_VEC_ELT (inner_args, i);
4040 else if (require_all_args)
4041 /* There must be a default arg in this case. */
4042 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4048 if (arg == error_mark_node)
4050 if (complain & tf_error)
4051 error ("template argument %d is invalid", i + 1);
4054 arg = convert_template_argument (TREE_VALUE (parm),
4055 arg, new_args, complain, i,
4058 if (arg == error_mark_node)
4060 TREE_VEC_ELT (new_inner_args, i) = arg;
4064 return error_mark_node;
4066 return new_inner_args;
4069 /* Returns 1 if template args OT and NT are equivalent. */
4072 template_args_equal (tree ot, tree nt)
4077 if (TREE_CODE (nt) == TREE_VEC)
4078 /* For member templates */
4079 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4080 else if (TYPE_P (nt))
4081 return TYPE_P (ot) && same_type_p (ot, nt);
4082 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4085 return cp_tree_equal (ot, nt);
4088 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4089 of template arguments. Returns 0 otherwise. */
4092 comp_template_args (tree oldargs, tree newargs)
4096 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4099 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4101 tree nt = TREE_VEC_ELT (newargs, i);
4102 tree ot = TREE_VEC_ELT (oldargs, i);
4104 if (! template_args_equal (ot, nt))
4110 /* Given class template name and parameter list, produce a user-friendly name
4111 for the instantiation. */
4114 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4116 static struct obstack scratch_obstack;
4117 static char *scratch_firstobj;
4120 if (!scratch_firstobj)
4121 gcc_obstack_init (&scratch_obstack);
4123 obstack_free (&scratch_obstack, scratch_firstobj);
4124 scratch_firstobj = (char *) obstack_alloc (&scratch_obstack, 1);
4126 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4127 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4131 nparms = TREE_VEC_LENGTH (parms);
4132 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4133 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4134 for (i = 0; i < nparms; i++)
4136 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4137 tree arg = TREE_VEC_ELT (arglist, i);
4142 if (TREE_CODE (parm) == TYPE_DECL)
4144 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4147 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4149 if (TREE_CODE (arg) == TEMPLATE_DECL)
4151 /* Already substituted with real template. Just output
4152 the template name here */
4153 tree context = DECL_CONTEXT (arg);
4156 /* The template may be defined in a namespace, or
4157 may be a member template. */
4158 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4159 || CLASS_TYPE_P (context));
4160 cat (decl_as_string (DECL_CONTEXT (arg),
4161 TFF_PLAIN_IDENTIFIER));
4164 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4167 /* Output the parameter declaration. */
4168 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4172 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4174 /* No need to check arglist against parmlist here; we did that
4175 in coerce_template_parms, called from lookup_template_class. */
4176 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4179 char *bufp = obstack_next_free (&scratch_obstack);
4181 while (bufp[offset - 1] == ' ')
4183 obstack_blank_fast (&scratch_obstack, offset);
4185 /* B<C<char> >, not B<C<char>> */
4186 if (bufp[offset - 1] == '>')
4191 return (char *) obstack_base (&scratch_obstack);
4195 classtype_mangled_name (tree t)
4197 if (CLASSTYPE_TEMPLATE_INFO (t)
4198 /* Specializations have already had their names set up in
4199 lookup_template_class. */
4200 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4202 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4204 /* For non-primary templates, the template parameters are
4205 implicit from their surrounding context. */
4206 if (PRIMARY_TEMPLATE_P (tmpl))
4208 tree name = DECL_NAME (tmpl);
4209 char *mangled_name = mangle_class_name_for_template
4210 (IDENTIFIER_POINTER (name),
4211 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4212 CLASSTYPE_TI_ARGS (t));
4213 tree id = get_identifier (mangled_name);
4214 IDENTIFIER_TEMPLATE (id) = name;
4219 return TYPE_IDENTIFIER (t);
4223 add_pending_template (tree d)
4225 tree ti = (TYPE_P (d)
4226 ? CLASSTYPE_TEMPLATE_INFO (d)
4227 : DECL_TEMPLATE_INFO (d));
4231 if (TI_PENDING_TEMPLATE_FLAG (ti))
4234 /* We are called both from instantiate_decl, where we've already had a
4235 tinst_level pushed, and instantiate_template, where we haven't.
4237 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4240 push_tinst_level (d);
4242 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4243 if (last_pending_template)
4244 TREE_CHAIN (last_pending_template) = pt;
4246 pending_templates = pt;
4248 last_pending_template = pt;
4250 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4257 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4258 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4259 documentation for TEMPLATE_ID_EXPR. */
4262 lookup_template_function (tree fns, tree arglist)
4266 if (fns == error_mark_node || arglist == error_mark_node)
4267 return error_mark_node;
4269 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4270 gcc_assert (fns && (is_overloaded_fn (fns)
4271 || TREE_CODE (fns) == IDENTIFIER_NODE));
4273 if (BASELINK_P (fns))
4275 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4277 BASELINK_FUNCTIONS (fns),
4282 type = TREE_TYPE (fns);
4283 if (TREE_CODE (fns) == OVERLOAD || !type)
4284 type = unknown_type_node;
4286 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4289 /* Within the scope of a template class S<T>, the name S gets bound
4290 (in build_self_reference) to a TYPE_DECL for the class, not a
4291 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4292 or one of its enclosing classes, and that type is a template,
4293 return the associated TEMPLATE_DECL. Otherwise, the original
4294 DECL is returned. */
4297 maybe_get_template_decl_from_type_decl (tree decl)
4299 return (decl != NULL_TREE
4300 && TREE_CODE (decl) == TYPE_DECL
4301 && DECL_ARTIFICIAL (decl)
4302 && CLASS_TYPE_P (TREE_TYPE (decl))
4303 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4304 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4307 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4308 parameters, find the desired type.
4310 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4312 IN_DECL, if non-NULL, is the template declaration we are trying to
4315 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4316 the class we are looking up.
4318 Issue error and warning messages under control of COMPLAIN.
4320 If the template class is really a local class in a template
4321 function, then the FUNCTION_CONTEXT is the function in which it is
4324 ??? Note that this function is currently called *twice* for each
4325 template-id: the first time from the parser, while creating the
4326 incomplete type (finish_template_type), and the second type during the
4327 real instantiation (instantiate_template_class). This is surely something
4328 that we want to avoid. It also causes some problems with argument
4329 coercion (see convert_nontype_argument for more information on this). */
4332 lookup_template_class (tree d1,
4337 tsubst_flags_t complain)
4339 tree template = NULL_TREE, parmlist;
4342 timevar_push (TV_NAME_LOOKUP);
4344 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4346 tree value = innermost_non_namespace_value (d1);
4347 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4352 push_decl_namespace (context);
4353 template = lookup_name (d1);
4354 template = maybe_get_template_decl_from_type_decl (template);
4356 pop_decl_namespace ();
4359 context = DECL_CONTEXT (template);
4361 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4363 tree type = TREE_TYPE (d1);
4365 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4366 an implicit typename for the second A. Deal with it. */
4367 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4368 type = TREE_TYPE (type);
4370 if (CLASSTYPE_TEMPLATE_INFO (type))
4372 template = CLASSTYPE_TI_TEMPLATE (type);
4373 d1 = DECL_NAME (template);
4376 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4377 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4379 template = TYPE_TI_TEMPLATE (d1);
4380 d1 = DECL_NAME (template);
4382 else if (TREE_CODE (d1) == TEMPLATE_DECL
4383 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4386 d1 = DECL_NAME (template);
4387 context = DECL_CONTEXT (template);
4390 /* Issue an error message if we didn't find a template. */
4393 if (complain & tf_error)
4394 error ("%qT is not a template", d1);
4395 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4398 if (TREE_CODE (template) != TEMPLATE_DECL
4399 /* Make sure it's a user visible template, if it was named by
4401 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4402 && !PRIMARY_TEMPLATE_P (template)))
4404 if (complain & tf_error)
4406 error ("non-template type %qT used as a template", d1);
4408 error ("for template declaration %q+D", in_decl);
4410 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4413 complain &= ~tf_user;
4415 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4417 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4418 template arguments */
4423 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4425 /* Consider an example where a template template parameter declared as
4427 template <class T, class U = std::allocator<T> > class TT
4429 The template parameter level of T and U are one level larger than
4430 of TT. To proper process the default argument of U, say when an
4431 instantiation `TT<int>' is seen, we need to build the full
4432 arguments containing {int} as the innermost level. Outer levels,
4433 available when not appearing as default template argument, can be
4434 obtained from `current_template_args ()'.
4436 Suppose that TT is later substituted with std::vector. The above
4437 instantiation is `TT<int, std::allocator<T> >' with TT at
4438 level 1, and T at level 2, while the template arguments at level 1
4439 becomes {std::vector} and the inner level 2 is {int}. */
4441 if (current_template_parms)
4442 arglist = add_to_template_args (current_template_args (), arglist);
4444 arglist2 = coerce_template_parms (parmlist, arglist, template,
4446 /*require_all_args=*/true,
4447 /*use_default_args=*/true);
4448 if (arglist2 == error_mark_node
4449 || (!uses_template_parms (arglist2)
4450 && check_instantiated_args (template, arglist2, complain)))
4451 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4453 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4454 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4458 tree template_type = TREE_TYPE (template);
4461 tree found = NULL_TREE;
4464 int is_partial_instantiation;
4466 gen_tmpl = most_general_template (template);
4467 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4468 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4469 arg_depth = TMPL_ARGS_DEPTH (arglist);
4471 if (arg_depth == 1 && parm_depth > 1)
4473 /* We've been given an incomplete set of template arguments.
4476 template <class T> struct S1 {
4477 template <class U> struct S2 {};
4478 template <class U> struct S2<U*> {};
4481 we will be called with an ARGLIST of `U*', but the
4482 TEMPLATE will be `template <class T> template
4483 <class U> struct S1<T>::S2'. We must fill in the missing
4486 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4488 arg_depth = TMPL_ARGS_DEPTH (arglist);
4491 /* Now we should have enough arguments. */
4492 gcc_assert (parm_depth == arg_depth);
4494 /* From here on, we're only interested in the most general
4496 template = gen_tmpl;
4498 /* Calculate the BOUND_ARGS. These will be the args that are
4499 actually tsubst'd into the definition to create the
4503 /* We have multiple levels of arguments to coerce, at once. */
4505 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4507 tree bound_args = make_tree_vec (parm_depth);
4509 for (i = saved_depth,
4510 t = DECL_TEMPLATE_PARMS (template);
4511 i > 0 && t != NULL_TREE;
4512 --i, t = TREE_CHAIN (t))
4514 tree a = coerce_template_parms (TREE_VALUE (t),
4517 /*require_all_args=*/true,
4518 /*use_default_args=*/true);
4520 /* Don't process further if one of the levels fails. */
4521 if (a == error_mark_node)
4523 /* Restore the ARGLIST to its full size. */
4524 TREE_VEC_LENGTH (arglist) = saved_depth;
4525 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4528 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4530 /* We temporarily reduce the length of the ARGLIST so
4531 that coerce_template_parms will see only the arguments
4532 corresponding to the template parameters it is
4534 TREE_VEC_LENGTH (arglist)--;
4537 /* Restore the ARGLIST to its full size. */
4538 TREE_VEC_LENGTH (arglist) = saved_depth;
4540 arglist = bound_args;
4544 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4545 INNERMOST_TEMPLATE_ARGS (arglist),
4548 /*require_all_args=*/true,
4549 /*use_default_args=*/true);
4551 if (arglist == error_mark_node)
4552 /* We were unable to bind the arguments. */
4553 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4555 /* In the scope of a template class, explicit references to the
4556 template class refer to the type of the template, not any
4557 instantiation of it. For example, in:
4559 template <class T> class C { void f(C<T>); }
4561 the `C<T>' is just the same as `C'. Outside of the
4562 class, however, such a reference is an instantiation. */
4563 if (comp_template_args (TYPE_TI_ARGS (template_type),
4566 found = template_type;
4568 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4572 for (ctx = current_class_type;
4573 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4575 ? TYPE_CONTEXT (ctx)
4576 : DECL_CONTEXT (ctx)))
4577 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4580 /* We're not in the scope of the class, so the
4581 TEMPLATE_TYPE is not the type we want after all. */
4587 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4589 /* If we already have this specialization, return it. */
4590 found = retrieve_specialization (template, arglist,
4591 /*class_specializations_p=*/false);
4593 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4595 /* This type is a "partial instantiation" if any of the template
4596 arguments still involve template parameters. Note that we set
4597 IS_PARTIAL_INSTANTIATION for partial specializations as
4599 is_partial_instantiation = uses_template_parms (arglist);
4601 /* If the deduced arguments are invalid, then the binding
4603 if (!is_partial_instantiation
4604 && check_instantiated_args (template,
4605 INNERMOST_TEMPLATE_ARGS (arglist),
4607 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4609 if (!is_partial_instantiation
4610 && !PRIMARY_TEMPLATE_P (template)
4611 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4613 found = xref_tag_from_type (TREE_TYPE (template),
4614 DECL_NAME (template),
4615 /*tag_scope=*/ts_global);
4616 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4619 context = tsubst (DECL_CONTEXT (template), arglist,
4622 context = global_namespace;
4624 /* Create the type. */
4625 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4627 if (!is_partial_instantiation)
4629 set_current_access_from_decl (TYPE_NAME (template_type));
4630 t = start_enum (TYPE_IDENTIFIER (template_type));
4633 /* We don't want to call start_enum for this type, since
4634 the values for the enumeration constants may involve
4635 template parameters. And, no one should be interested
4636 in the enumeration constants for such a type. */
4637 t = make_node (ENUMERAL_TYPE);
4641 t = make_aggr_type (TREE_CODE (template_type));
4642 CLASSTYPE_DECLARED_CLASS (t)
4643 = CLASSTYPE_DECLARED_CLASS (template_type);
4644 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4645 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4647 /* A local class. Make sure the decl gets registered properly. */
4648 if (context == current_function_decl)
4649 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
4652 /* If we called start_enum or pushtag above, this information
4653 will already be set up. */
4656 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4658 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4659 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4660 TYPE_STUB_DECL (t) = type_decl;
4661 DECL_SOURCE_LOCATION (type_decl)
4662 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4665 type_decl = TYPE_NAME (t);
4667 TREE_PRIVATE (type_decl)
4668 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4669 TREE_PROTECTED (type_decl)
4670 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4671 DECL_IN_SYSTEM_HEADER (type_decl)
4672 = DECL_IN_SYSTEM_HEADER (template);
4673 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
4675 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
4676 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
4679 /* Set up the template information. We have to figure out which
4680 template is the immediate parent if this is a full
4682 if (parm_depth == 1 || is_partial_instantiation
4683 || !PRIMARY_TEMPLATE_P (template))
4684 /* This case is easy; there are no member templates involved. */
4688 /* This is a full instantiation of a member template. Look
4689 for a partial instantiation of which this is an instance. */
4691 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4692 found; found = TREE_CHAIN (found))
4695 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4697 /* We only want partial instantiations, here, not
4698 specializations or full instantiations. */
4699 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4700 || !uses_template_parms (TREE_VALUE (found)))
4703 /* Temporarily reduce by one the number of levels in the
4704 ARGLIST and in FOUND so as to avoid comparing the
4705 last set of arguments. */
4706 TREE_VEC_LENGTH (arglist)--;
4707 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4709 /* See if the arguments match. If they do, then TMPL is
4710 the partial instantiation we want. */
4711 success = comp_template_args (TREE_PURPOSE (found), arglist);
4713 /* Restore the argument vectors to their full size. */
4714 TREE_VEC_LENGTH (arglist)++;
4715 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4726 /* There was no partial instantiation. This happens
4727 where C<T> is a member template of A<T> and it's used
4730 template <typename T> struct B { A<T>::C<int> m; };
4733 Create the partial instantiation.
4735 TREE_VEC_LENGTH (arglist)--;
4736 found = tsubst (template, arglist, complain, NULL_TREE);
4737 TREE_VEC_LENGTH (arglist)++;
4741 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4742 DECL_TEMPLATE_INSTANTIATIONS (template)
4743 = tree_cons (arglist, t,
4744 DECL_TEMPLATE_INSTANTIATIONS (template));
4746 if (TREE_CODE (t) == ENUMERAL_TYPE
4747 && !is_partial_instantiation)
4748 /* Now that the type has been registered on the instantiations
4749 list, we set up the enumerators. Because the enumeration
4750 constants may involve the enumeration type itself, we make
4751 sure to register the type first, and then create the
4752 constants. That way, doing tsubst_expr for the enumeration
4753 constants won't result in recursive calls here; we'll find
4754 the instantiation and exit above. */
4755 tsubst_enum (template_type, t, arglist);
4757 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4759 if (TREE_CODE (t) != ENUMERAL_TYPE)
4760 DECL_NAME (type_decl) = classtype_mangled_name (t);
4761 if (is_partial_instantiation)
4762 /* If the type makes use of template parameters, the
4763 code that generates debugging information will crash. */
4764 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4766 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4768 timevar_pop (TV_NAME_LOOKUP);
4775 struct pointer_set_t *visited;
4778 /* Called from for_each_template_parm via walk_tree. */
4781 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4784 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4785 tree_fn_t fn = pfd->fn;
4786 void *data = pfd->data;
4789 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4790 return error_mark_node;
4792 switch (TREE_CODE (t))
4795 if (TYPE_PTRMEMFUNC_P (t))
4801 if (!TYPE_TEMPLATE_INFO (t))
4803 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4804 fn, data, pfd->visited))
4805 return error_mark_node;
4809 /* Since we're not going to walk subtrees, we have to do this
4811 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4813 return error_mark_node;
4817 /* Check the return type. */
4818 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4819 return error_mark_node;
4821 /* Check the parameter types. Since default arguments are not
4822 instantiated until they are needed, the TYPE_ARG_TYPES may
4823 contain expressions that involve template parameters. But,
4824 no-one should be looking at them yet. And, once they're
4825 instantiated, they don't contain template parameters, so
4826 there's no point in looking at them then, either. */
4830 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4831 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4833 return error_mark_node;
4835 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4836 want walk_tree walking into them itself. */
4842 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4844 return error_mark_node;
4849 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4850 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4852 return error_mark_node;
4857 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4858 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4860 return error_mark_node;
4861 if (DECL_CONTEXT (t)
4862 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4864 return error_mark_node;
4867 case BOUND_TEMPLATE_TEMPLATE_PARM:
4868 /* Record template parameters such as `T' inside `TT<T>'. */
4869 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4870 return error_mark_node;
4873 case TEMPLATE_TEMPLATE_PARM:
4874 case TEMPLATE_TYPE_PARM:
4875 case TEMPLATE_PARM_INDEX:
4876 if (fn && (*fn)(t, data))
4877 return error_mark_node;
4879 return error_mark_node;
4883 /* A template template parameter is encountered. */
4884 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4885 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4886 return error_mark_node;
4888 /* Already substituted template template parameter */
4894 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4895 data, pfd->visited))
4896 return error_mark_node;
4900 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4901 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4902 (TREE_TYPE (t)), fn, data,
4904 return error_mark_node;
4909 /* If there's no type, then this thing must be some expression
4910 involving template parameters. */
4911 if (!fn && !TREE_TYPE (t))
4912 return error_mark_node;
4917 case REINTERPRET_CAST_EXPR:
4918 case CONST_CAST_EXPR:
4919 case STATIC_CAST_EXPR:
4920 case DYNAMIC_CAST_EXPR:
4924 case PSEUDO_DTOR_EXPR:
4926 return error_mark_node;
4930 /* If we do not handle this case specially, we end up walking
4931 the BINFO hierarchy, which is circular, and therefore
4932 confuses walk_tree. */
4934 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4936 return error_mark_node;
4943 /* We didn't find any template parameters we liked. */
4947 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4948 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4949 call FN with the parameter and the DATA.
4950 If FN returns nonzero, the iteration is terminated, and
4951 for_each_template_parm returns 1. Otherwise, the iteration
4952 continues. If FN never returns a nonzero value, the value
4953 returned by for_each_template_parm is 0. If FN is NULL, it is
4954 considered to be the function which always returns 1. */
4957 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4958 struct pointer_set_t *visited)
4960 struct pair_fn_data pfd;
4967 /* Walk the tree. (Conceptually, we would like to walk without
4968 duplicates, but for_each_template_parm_r recursively calls
4969 for_each_template_parm, so we would need to reorganize a fair
4970 bit to use walk_tree_without_duplicates, so we keep our own
4973 pfd.visited = visited;
4975 pfd.visited = pointer_set_create ();
4976 result = walk_tree (&t,
4977 for_each_template_parm_r,
4979 pfd.visited) != NULL_TREE;
4984 pointer_set_destroy (pfd.visited);
4991 /* Returns true if T depends on any template parameter. */
4994 uses_template_parms (tree t)
4997 int saved_processing_template_decl;
4999 saved_processing_template_decl = processing_template_decl;
5000 if (!saved_processing_template_decl)
5001 processing_template_decl = 1;
5003 dependent_p = dependent_type_p (t);
5004 else if (TREE_CODE (t) == TREE_VEC)
5005 dependent_p = any_dependent_template_arguments_p (t);
5006 else if (TREE_CODE (t) == TREE_LIST)
5007 dependent_p = (uses_template_parms (TREE_VALUE (t))
5008 || uses_template_parms (TREE_CHAIN (t)));
5009 else if (TREE_CODE (t) == TYPE_DECL)
5010 dependent_p = dependent_type_p (TREE_TYPE (t));
5013 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
5014 || TREE_CODE (t) == OVERLOAD
5015 || TREE_CODE (t) == BASELINK
5016 || TREE_CODE (t) == IDENTIFIER_NODE
5017 || CONSTANT_CLASS_P (t))
5018 dependent_p = (type_dependent_expression_p (t)
5019 || value_dependent_expression_p (t));
5022 gcc_assert (t == error_mark_node);
5023 dependent_p = false;
5026 processing_template_decl = saved_processing_template_decl;
5031 /* Returns true if T depends on any template parameter with level LEVEL. */
5034 uses_template_parms_level (tree t, int level)
5036 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
5039 static int tinst_depth;
5040 extern int max_tinst_depth;
5041 #ifdef GATHER_STATISTICS
5044 static int tinst_level_tick;
5045 static int last_template_error_tick;
5047 /* We're starting to instantiate D; record the template instantiation context
5048 for diagnostics and to restore it later. */
5051 push_tinst_level (tree d)
5055 if (tinst_depth >= max_tinst_depth)
5057 /* If the instantiation in question still has unbound template parms,
5058 we don't really care if we can't instantiate it, so just return.
5059 This happens with base instantiation for implicit `typename'. */
5060 if (uses_template_parms (d))
5063 last_template_error_tick = tinst_level_tick;
5064 error ("template instantiation depth exceeds maximum of %d (use "
5065 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5066 max_tinst_depth, d);
5068 print_instantiation_context ();
5073 new = make_node (TINST_LEVEL);
5074 TINST_DECL (new) = d;
5075 TINST_LOCATION (new) = input_location;
5076 TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
5077 TREE_CHAIN (new) = current_tinst_level;
5078 current_tinst_level = new;
5081 #ifdef GATHER_STATISTICS
5082 if (tinst_depth > depth_reached)
5083 depth_reached = tinst_depth;
5090 /* We're done instantiating this template; return to the instantiation
5094 pop_tinst_level (void)
5096 tree old = current_tinst_level;
5098 /* Restore the filename and line number stashed away when we started
5099 this instantiation. */
5100 input_location = TINST_LOCATION (old);
5101 in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
5102 current_tinst_level = TREE_CHAIN (old);
5107 /* We're instantiating a deferred template; restore the template
5108 instantiation context in which the instantiation was requested, which
5109 is one step out from LEVEL. */
5112 reopen_tinst_level (tree level)
5117 for (t = level; t; t = TREE_CHAIN (t))
5120 current_tinst_level = level;
5124 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5125 vector of template arguments, as for tsubst.
5127 Returns an appropriate tsubst'd friend declaration. */
5130 tsubst_friend_function (tree decl, tree args)
5134 if (TREE_CODE (decl) == FUNCTION_DECL
5135 && DECL_TEMPLATE_INSTANTIATION (decl)
5136 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5137 /* This was a friend declared with an explicit template
5138 argument list, e.g.:
5142 to indicate that f was a template instantiation, not a new
5143 function declaration. Now, we have to figure out what
5144 instantiation of what template. */
5146 tree template_id, arglist, fns;
5149 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5151 /* Friend functions are looked up in the containing namespace scope.
5152 We must enter that scope, to avoid finding member functions of the
5153 current cless with same name. */
5154 push_nested_namespace (ns);
5155 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5156 tf_warning_or_error, NULL_TREE);
5157 pop_nested_namespace (ns);
5158 arglist = tsubst (DECL_TI_ARGS (decl), args,
5159 tf_warning_or_error, NULL_TREE);
5160 template_id = lookup_template_function (fns, arglist);
5162 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
5163 tmpl = determine_specialization (template_id, new_friend,
5165 /*need_member_template=*/0,
5166 TREE_VEC_LENGTH (args));
5167 return instantiate_template (tmpl, new_args, tf_error);
5170 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
5172 /* The NEW_FRIEND will look like an instantiation, to the
5173 compiler, but is not an instantiation from the point of view of
5174 the language. For example, we might have had:
5176 template <class T> struct S {
5177 template <class U> friend void f(T, U);
5180 Then, in S<int>, template <class U> void f(int, U) is not an
5181 instantiation of anything. */
5182 if (new_friend == error_mark_node)
5183 return error_mark_node;
5185 DECL_USE_TEMPLATE (new_friend) = 0;
5186 if (TREE_CODE (decl) == TEMPLATE_DECL)
5188 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5189 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5190 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5193 /* The mangled name for the NEW_FRIEND is incorrect. The function
5194 is not a template instantiation and should not be mangled like
5195 one. Therefore, we forget the mangling here; we'll recompute it
5196 later if we need it. */
5197 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5199 SET_DECL_RTL (new_friend, NULL_RTX);
5200 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5203 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5206 tree new_friend_template_info;
5207 tree new_friend_result_template_info;
5209 int new_friend_is_defn;
5211 /* We must save some information from NEW_FRIEND before calling
5212 duplicate decls since that function will free NEW_FRIEND if
5214 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5215 new_friend_is_defn =
5216 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5217 (template_for_substitution (new_friend)))
5219 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5221 /* This declaration is a `primary' template. */
5222 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5224 new_friend_result_template_info
5225 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5228 new_friend_result_template_info = NULL_TREE;
5230 /* Inside pushdecl_namespace_level, we will push into the
5231 current namespace. However, the friend function should go
5232 into the namespace of the template. */
5233 ns = decl_namespace_context (new_friend);
5234 push_nested_namespace (ns);
5235 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
5236 pop_nested_namespace (ns);
5238 if (old_decl == error_mark_node)
5239 return error_mark_node;
5241 if (old_decl != new_friend)
5243 /* This new friend declaration matched an existing
5244 declaration. For example, given:
5246 template <class T> void f(T);
5247 template <class U> class C {
5248 template <class T> friend void f(T) {}
5251 the friend declaration actually provides the definition
5252 of `f', once C has been instantiated for some type. So,
5253 old_decl will be the out-of-class template declaration,
5254 while new_friend is the in-class definition.
5256 But, if `f' was called before this point, the
5257 instantiation of `f' will have DECL_TI_ARGS corresponding
5258 to `T' but not to `U', references to which might appear
5259 in the definition of `f'. Previously, the most general
5260 template for an instantiation of `f' was the out-of-class
5261 version; now it is the in-class version. Therefore, we
5262 run through all specialization of `f', adding to their
5263 DECL_TI_ARGS appropriately. In particular, they need a
5264 new set of outer arguments, corresponding to the
5265 arguments for this class instantiation.
5267 The same situation can arise with something like this:
5270 template <class T> class C {
5274 when `C<int>' is instantiated. Now, `f(int)' is defined
5277 if (!new_friend_is_defn)
5278 /* On the other hand, if the in-class declaration does
5279 *not* provide a definition, then we don't want to alter
5280 existing definitions. We can just leave everything
5285 /* Overwrite whatever template info was there before, if
5286 any, with the new template information pertaining to
5288 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5290 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5291 reregister_specialization (new_friend,
5292 most_general_template (old_decl),
5297 tree new_friend_args;
5299 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5300 = new_friend_result_template_info;
5302 new_friend_args = TI_ARGS (new_friend_template_info);
5303 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5307 tree spec = TREE_VALUE (t);
5310 = add_outermost_template_args (new_friend_args,
5311 DECL_TI_ARGS (spec));
5314 /* Now, since specializations are always supposed to
5315 hang off of the most general template, we must move
5317 t = most_general_template (old_decl);
5320 DECL_TEMPLATE_SPECIALIZATIONS (t)
5321 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5322 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5323 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5328 /* The information from NEW_FRIEND has been merged into OLD_DECL
5329 by duplicate_decls. */
5330 new_friend = old_decl;
5335 tree context = DECL_CONTEXT (new_friend);
5339 template <class T> class C {
5340 template <class U> friend void C1<U>::f (); // case 1
5341 friend void C2<T>::f (); // case 2
5343 we only need to make sure CONTEXT is a complete type for
5344 case 2. To distinguish between the two cases, we note that
5345 CONTEXT of case 1 remains dependent type after tsubst while
5346 this isn't true for case 2. */
5347 ++processing_template_decl;
5348 dependent_p = dependent_type_p (context);
5349 --processing_template_decl;
5352 && !complete_type_or_else (context, NULL_TREE))
5353 return error_mark_node;
5355 if (COMPLETE_TYPE_P (context))
5357 /* Check to see that the declaration is really present, and,
5358 possibly obtain an improved declaration. */
5359 tree fn = check_classfn (context,
5360 new_friend, NULL_TREE);
5370 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5371 template arguments, as for tsubst.
5373 Returns an appropriate tsubst'd friend type or error_mark_node on
5377 tsubst_friend_class (tree friend_tmpl, tree args)
5383 context = DECL_CONTEXT (friend_tmpl);
5387 if (TREE_CODE (context) == NAMESPACE_DECL)
5388 push_nested_namespace (context);
5390 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5393 /* First, we look for a class template. */
5394 tmpl = lookup_name (DECL_NAME (friend_tmpl));
5396 /* But, if we don't find one, it might be because we're in a
5397 situation like this:
5405 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5406 for `S<int>', not the TEMPLATE_DECL. */
5407 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5409 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
5410 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5413 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5415 /* The friend template has already been declared. Just
5416 check to see that the declarations match, and install any new
5417 default parameters. We must tsubst the default parameters,
5418 of course. We only need the innermost template parameters
5419 because that is all that redeclare_class_template will look
5421 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5422 > TMPL_ARGS_DEPTH (args))
5425 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5426 args, tf_warning_or_error);
5427 redeclare_class_template (TREE_TYPE (tmpl), parms);
5430 friend_type = TREE_TYPE (tmpl);
5434 /* The friend template has not already been declared. In this
5435 case, the instantiation of the template class will cause the
5436 injection of this template into the global scope. */
5437 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
5438 if (tmpl == error_mark_node)
5439 return error_mark_node;
5441 /* The new TMPL is not an instantiation of anything, so we
5442 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5443 the new type because that is supposed to be the corresponding
5444 template decl, i.e., TMPL. */
5445 DECL_USE_TEMPLATE (tmpl) = 0;
5446 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5447 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5448 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5449 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5451 /* Inject this template into the global scope. */
5452 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
5457 if (TREE_CODE (context) == NAMESPACE_DECL)
5458 pop_nested_namespace (context);
5460 pop_nested_class ();
5466 /* Returns zero if TYPE cannot be completed later due to circularity.
5467 Otherwise returns one. */
5470 can_complete_type_without_circularity (tree type)
5472 if (type == NULL_TREE || type == error_mark_node)
5474 else if (COMPLETE_TYPE_P (type))
5476 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5477 return can_complete_type_without_circularity (TREE_TYPE (type));
5478 else if (CLASS_TYPE_P (type)
5479 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5486 instantiate_class_template (tree type)
5488 tree template, args, pattern, t, member;
5493 if (type == error_mark_node)
5494 return error_mark_node;
5496 if (TYPE_BEING_DEFINED (type)
5497 || COMPLETE_TYPE_P (type)
5498 || dependent_type_p (type))
5501 /* Figure out which template is being instantiated. */
5502 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5503 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5505 /* Determine what specialization of the original template to
5507 t = most_specialized_class (type, template);
5508 if (t == error_mark_node)
5510 TYPE_BEING_DEFINED (type) = 1;
5511 return error_mark_node;
5515 /* This TYPE is actually an instantiation of a partial
5516 specialization. We replace the innermost set of ARGS with
5517 the arguments appropriate for substitution. For example,
5520 template <class T> struct S {};
5521 template <class T> struct S<T*> {};
5523 and supposing that we are instantiating S<int*>, ARGS will
5524 presently be {int*} -- but we need {int}. */
5525 pattern = TREE_TYPE (t);
5526 args = TREE_PURPOSE (t);
5530 pattern = TREE_TYPE (template);
5531 args = CLASSTYPE_TI_ARGS (type);
5534 /* If the template we're instantiating is incomplete, then clearly
5535 there's nothing we can do. */
5536 if (!COMPLETE_TYPE_P (pattern))
5539 /* If we've recursively instantiated too many templates, stop. */
5540 if (! push_tinst_level (type))
5543 /* Now we're really doing the instantiation. Mark the type as in
5544 the process of being defined. */
5545 TYPE_BEING_DEFINED (type) = 1;
5547 /* We may be in the middle of deferred access check. Disable
5549 push_deferring_access_checks (dk_no_deferred);
5551 push_to_top_level ();
5553 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5555 /* Set the input location to the template definition. This is needed
5556 if tsubsting causes an error. */
5557 typedecl = TYPE_MAIN_DECL (type);
5558 input_location = DECL_SOURCE_LOCATION (typedecl);
5559 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
5561 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5562 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5563 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5564 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5565 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5566 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5567 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5568 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5569 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5570 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5571 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5572 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5573 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5574 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5575 if (ANON_AGGR_TYPE_P (pattern))
5576 SET_ANON_AGGR_TYPE_P (type);
5577 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
5579 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
5580 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
5583 pbinfo = TYPE_BINFO (pattern);
5585 /* We should never instantiate a nested class before its enclosing
5586 class; we need to look up the nested class by name before we can
5587 instantiate it, and that lookup should instantiate the enclosing
5589 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5590 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5591 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5593 base_list = NULL_TREE;
5594 if (BINFO_N_BASE_BINFOS (pbinfo))
5597 tree context = TYPE_CONTEXT (type);
5601 /* We must enter the scope containing the type, as that is where
5602 the accessibility of types named in dependent bases are
5604 pushed_scope = push_scope (context ? context : global_namespace);
5606 /* Substitute into each of the bases to determine the actual
5608 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5611 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5613 /* Substitute to figure out the base class. */
5614 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5615 if (base == error_mark_node)
5618 base_list = tree_cons (access, base, base_list);
5619 if (BINFO_VIRTUAL_P (pbase_binfo))
5620 TREE_TYPE (base_list) = integer_type_node;
5623 /* The list is now in reverse order; correct that. */
5624 base_list = nreverse (base_list);
5627 pop_scope (pushed_scope);
5629 /* Now call xref_basetypes to set up all the base-class
5631 xref_basetypes (type, base_list);
5634 /* Now that our base classes are set up, enter the scope of the
5635 class, so that name lookups into base classes, etc. will work
5636 correctly. This is precisely analogous to what we do in
5637 begin_class_definition when defining an ordinary non-template
5641 /* Now members are processed in the order of declaration. */
5642 for (member = CLASSTYPE_DECL_LIST (pattern);
5643 member; member = TREE_CHAIN (member))
5645 tree t = TREE_VALUE (member);
5647 if (TREE_PURPOSE (member))
5651 /* Build new CLASSTYPE_NESTED_UTDS. */
5654 bool class_template_p;
5656 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
5657 && TYPE_LANG_SPECIFIC (t)
5658 && CLASSTYPE_IS_TEMPLATE (t));
5659 /* If the member is a class template, then -- even after
5660 substitution -- there may be dependent types in the
5661 template argument list for the class. We increment
5662 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5663 that function will assume that no types are dependent
5664 when outside of a template. */
5665 if (class_template_p)
5666 ++processing_template_decl;
5667 newtag = tsubst (t, args, tf_error, NULL_TREE);
5668 if (class_template_p)
5669 --processing_template_decl;
5670 if (newtag == error_mark_node)
5673 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5675 tree name = TYPE_IDENTIFIER (t);
5677 if (class_template_p)
5678 /* Unfortunately, lookup_template_class sets
5679 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5680 instantiation (i.e., for the type of a member
5681 template class nested within a template class.)
5682 This behavior is required for
5683 maybe_process_partial_specialization to work
5684 correctly, but is not accurate in this case;
5685 the TAG is not an instantiation of anything.
5686 (The corresponding TEMPLATE_DECL is an
5687 instantiation, but the TYPE is not.) */
5688 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5690 /* Now, we call pushtag to put this NEWTAG into the scope of
5691 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5692 pushtag calling push_template_decl. We don't have to do
5693 this for enums because it will already have been done in
5696 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5697 pushtag (name, newtag, /*tag_scope=*/ts_current);
5700 else if (TREE_CODE (t) == FUNCTION_DECL
5701 || DECL_FUNCTION_TEMPLATE_P (t))
5703 /* Build new TYPE_METHODS. */
5706 if (TREE_CODE (t) == TEMPLATE_DECL)
5707 ++processing_template_decl;
5708 r = tsubst (t, args, tf_error, NULL_TREE);
5709 if (TREE_CODE (t) == TEMPLATE_DECL)
5710 --processing_template_decl;
5711 set_current_access_from_decl (r);
5712 finish_member_declaration (r);
5716 /* Build new TYPE_FIELDS. */
5718 if (TREE_CODE (t) != CONST_DECL)
5722 /* The the file and line for this declaration, to
5723 assist in error message reporting. Since we
5724 called push_tinst_level above, we don't need to
5726 input_location = DECL_SOURCE_LOCATION (t);
5728 if (TREE_CODE (t) == TEMPLATE_DECL)
5729 ++processing_template_decl;
5730 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
5731 if (TREE_CODE (t) == TEMPLATE_DECL)
5732 --processing_template_decl;
5733 if (TREE_CODE (r) == VAR_DECL)
5737 [t]he initialization (and any associated
5738 side-effects) of a static data member does
5739 not occur unless the static data member is
5740 itself used in a way that requires the
5741 definition of the static data member to
5744 Therefore, we do not substitute into the
5745 initialized for the static data member here. */
5746 finish_static_data_member_decl
5749 /*init_const_expr_p=*/false,
5750 /*asmspec_tree=*/NULL_TREE,
5752 if (DECL_INITIALIZED_IN_CLASS_P (r))
5753 check_static_variable_definition (r, TREE_TYPE (r));
5755 else if (TREE_CODE (r) == FIELD_DECL)
5757 /* Determine whether R has a valid type and can be
5758 completed later. If R is invalid, then it is
5759 replaced by error_mark_node so that it will not be
5760 added to TYPE_FIELDS. */
5761 tree rtype = TREE_TYPE (r);
5762 if (can_complete_type_without_circularity (rtype))
5763 complete_type (rtype);
5765 if (!COMPLETE_TYPE_P (rtype))
5767 cxx_incomplete_type_error (r, rtype);
5768 r = error_mark_node;
5772 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5773 such a thing will already have been added to the field
5774 list by tsubst_enum in finish_member_declaration in the
5775 CLASSTYPE_NESTED_UTDS case above. */
5776 if (!(TREE_CODE (r) == TYPE_DECL
5777 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5778 && DECL_ARTIFICIAL (r)))
5780 set_current_access_from_decl (r);
5781 finish_member_declaration (r);
5788 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5790 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5792 tree friend_type = t;
5793 bool adjust_processing_template_decl = false;
5795 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5797 /* template <class T> friend class C; */
5798 friend_type = tsubst_friend_class (friend_type, args);
5799 adjust_processing_template_decl = true;
5801 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5803 /* template <class T> friend class C::D; */
5804 friend_type = tsubst (friend_type, args,
5805 tf_warning_or_error, NULL_TREE);
5806 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5807 friend_type = TREE_TYPE (friend_type);
5808 adjust_processing_template_decl = true;
5810 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5812 /* This could be either
5816 when dependent_type_p is false or
5818 template <class U> friend class T::C;
5821 friend_type = tsubst (friend_type, args,
5822 tf_warning_or_error, NULL_TREE);
5823 /* Bump processing_template_decl for correct
5824 dependent_type_p calculation. */
5825 ++processing_template_decl;
5826 if (dependent_type_p (friend_type))
5827 adjust_processing_template_decl = true;
5828 --processing_template_decl;
5830 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
5831 && hidden_name_p (TYPE_NAME (friend_type)))
5835 where C hasn't been declared yet. Let's lookup name
5836 from namespace scope directly, bypassing any name that
5837 come from dependent base class. */
5838 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5840 /* The call to xref_tag_from_type does injection for friend
5842 push_nested_namespace (ns);
5844 xref_tag_from_type (friend_type, NULL_TREE,
5845 /*tag_scope=*/ts_current);
5846 pop_nested_namespace (ns);
5848 else if (uses_template_parms (friend_type))
5849 /* friend class C<T>; */
5850 friend_type = tsubst (friend_type, args,
5851 tf_warning_or_error, NULL_TREE);
5856 where C is already declared or
5858 friend class C<int>;
5860 We don't have to do anything in these cases. */
5862 if (adjust_processing_template_decl)
5863 /* Trick make_friend_class into realizing that the friend
5864 we're adding is a template, not an ordinary class. It's
5865 important that we use make_friend_class since it will
5866 perform some error-checking and output cross-reference
5868 ++processing_template_decl;
5870 if (friend_type != error_mark_node)
5871 make_friend_class (type, friend_type, /*complain=*/false);
5873 if (adjust_processing_template_decl)
5874 --processing_template_decl;
5878 /* Build new DECL_FRIENDLIST. */
5881 /* The the file and line for this declaration, to
5882 assist in error message reporting. Since we
5883 called push_tinst_level above, we don't need to
5885 input_location = DECL_SOURCE_LOCATION (t);
5887 if (TREE_CODE (t) == TEMPLATE_DECL)
5889 ++processing_template_decl;
5890 push_deferring_access_checks (dk_no_check);
5893 r = tsubst_friend_function (t, args);
5894 add_friend (type, r, /*complain=*/false);
5895 if (TREE_CODE (t) == TEMPLATE_DECL)
5897 pop_deferring_access_checks ();
5898 --processing_template_decl;
5904 /* Set the file and line number information to whatever is given for
5905 the class itself. This puts error messages involving generated
5906 implicit functions at a predictable point, and the same point
5907 that would be used for non-template classes. */
5908 input_location = DECL_SOURCE_LOCATION (typedecl);
5910 unreverse_member_declarations (type);
5911 finish_struct_1 (type);
5912 TYPE_BEING_DEFINED (type) = 0;
5914 /* Now that the class is complete, instantiate default arguments for
5915 any member functions. We don't do this earlier because the
5916 default arguments may reference members of the class. */
5917 if (!PRIMARY_TEMPLATE_P (template))
5918 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5919 if (TREE_CODE (t) == FUNCTION_DECL
5920 /* Implicitly generated member functions will not have template
5921 information; they are not instantiations, but instead are
5922 created "fresh" for each instantiation. */
5923 && DECL_TEMPLATE_INFO (t))
5924 tsubst_default_arguments (t);
5927 pop_from_top_level ();
5928 pop_deferring_access_checks ();
5931 /* The vtable for a template class can be emitted in any translation
5932 unit in which the class is instantiated. When there is no key
5933 method, however, finish_struct_1 will already have added TYPE to
5934 the keyed_classes list. */
5935 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5936 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5942 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5948 else if (TYPE_P (t))
5949 r = tsubst (t, args, complain, in_decl);
5952 r = tsubst_expr (t, args, complain, in_decl);
5953 r = fold_non_dependent_expr (r);
5958 /* Substitute ARGS into the vector or list of template arguments T. */
5961 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5963 int len = TREE_VEC_LENGTH (t);
5964 int need_new = 0, i;
5965 tree *elts = (tree *) alloca (len * sizeof (tree));
5967 for (i = 0; i < len; i++)
5969 tree orig_arg = TREE_VEC_ELT (t, i);
5972 if (TREE_CODE (orig_arg) == TREE_VEC)
5973 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5975 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5977 if (new_arg == error_mark_node)
5978 return error_mark_node;
5981 if (new_arg != orig_arg)
5988 t = make_tree_vec (len);
5989 for (i = 0; i < len; i++)
5990 TREE_VEC_ELT (t, i) = elts[i];
5995 /* Return the result of substituting ARGS into the template parameters
5996 given by PARMS. If there are m levels of ARGS and m + n levels of
5997 PARMS, then the result will contain n levels of PARMS. For
5998 example, if PARMS is `template <class T> template <class U>
5999 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
6000 result will be `template <int*, double, class V>'. */
6003 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
6008 /* When substituting into a template, we must set
6009 PROCESSING_TEMPLATE_DECL as the template parameters may be
6010 dependent if they are based on one-another, and the dependency
6011 predicates are short-circuit outside of templates. */
6012 ++processing_template_decl;
6014 for (new_parms = &r;
6015 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
6016 new_parms = &(TREE_CHAIN (*new_parms)),
6017 parms = TREE_CHAIN (parms))
6020 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
6023 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
6025 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
6026 tree default_value = TREE_PURPOSE (tuple);
6027 tree parm_decl = TREE_VALUE (tuple);
6029 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
6030 if (TREE_CODE (parm_decl) == PARM_DECL
6031 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
6032 parm_decl = error_mark_node;
6033 default_value = tsubst_template_arg (default_value, args,
6034 complain, NULL_TREE);
6036 tuple = build_tree_list (default_value, parm_decl);
6037 TREE_VEC_ELT (new_vec, i) = tuple;
6041 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6042 - TMPL_ARGS_DEPTH (args)),
6043 new_vec, NULL_TREE);
6046 --processing_template_decl;
6051 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6052 type T. If T is not an aggregate or enumeration type, it is
6053 handled as if by tsubst. IN_DECL is as for tsubst. If
6054 ENTERING_SCOPE is nonzero, T is the context for a template which
6055 we are presently tsubst'ing. Return the substituted value. */
6058 tsubst_aggr_type (tree t,
6060 tsubst_flags_t complain,
6067 switch (TREE_CODE (t))
6070 if (TYPE_PTRMEMFUNC_P (t))
6071 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6073 /* Else fall through. */
6076 if (TYPE_TEMPLATE_INFO (t))
6081 bool saved_skip_evaluation;
6083 /* In "sizeof(X<I>)" we need to evaluate "I". */
6084 saved_skip_evaluation = skip_evaluation;
6085 skip_evaluation = false;
6087 /* First, determine the context for the type we are looking
6089 context = TYPE_CONTEXT (t);
6091 context = tsubst_aggr_type (context, args, complain,
6092 in_decl, /*entering_scope=*/1);
6094 /* Then, figure out what arguments are appropriate for the
6095 type we are trying to find. For example, given:
6097 template <class T> struct S;
6098 template <class T, class U> void f(T, U) { S<U> su; }
6100 and supposing that we are instantiating f<int, double>,
6101 then our ARGS will be {int, double}, but, when looking up
6102 S we only want {double}. */
6103 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6105 if (argvec == error_mark_node)
6106 r = error_mark_node;
6109 r = lookup_template_class (t, argvec, in_decl, context,
6110 entering_scope, complain);
6111 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6114 skip_evaluation = saved_skip_evaluation;
6119 /* This is not a template type, so there's nothing to do. */
6123 return tsubst (t, args, complain, in_decl);
6127 /* Substitute into the default argument ARG (a default argument for
6128 FN), which has the indicated TYPE. */
6131 tsubst_default_argument (tree fn, tree type, tree arg)
6133 tree saved_class_ptr = NULL_TREE;
6134 tree saved_class_ref = NULL_TREE;
6136 /* This default argument came from a template. Instantiate the
6137 default argument here, not in tsubst. In the case of
6146 we must be careful to do name lookup in the scope of S<T>,
6147 rather than in the current class. */
6148 push_access_scope (fn);
6149 /* The "this" pointer is not valid in a default argument. */
6152 saved_class_ptr = current_class_ptr;
6153 cp_function_chain->x_current_class_ptr = NULL_TREE;
6154 saved_class_ref = current_class_ref;
6155 cp_function_chain->x_current_class_ref = NULL_TREE;
6158 push_deferring_access_checks(dk_no_deferred);
6159 /* The default argument expression may cause implicitly defined
6160 member functions to be synthesized, which will result in garbage
6161 collection. We must treat this situation as if we were within
6162 the body of function so as to avoid collecting live data on the
6165 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6166 tf_warning_or_error, NULL_TREE);
6168 pop_deferring_access_checks();
6170 /* Restore the "this" pointer. */
6173 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6174 cp_function_chain->x_current_class_ref = saved_class_ref;
6177 pop_access_scope (fn);
6179 /* Make sure the default argument is reasonable. */
6180 arg = check_default_argument (type, arg);
6185 /* Substitute into all the default arguments for FN. */
6188 tsubst_default_arguments (tree fn)
6193 tmpl_args = DECL_TI_ARGS (fn);
6195 /* If this function is not yet instantiated, we certainly don't need
6196 its default arguments. */
6197 if (uses_template_parms (tmpl_args))
6200 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6202 arg = TREE_CHAIN (arg))
6203 if (TREE_PURPOSE (arg))
6204 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6206 TREE_PURPOSE (arg));
6209 /* Substitute the ARGS into the T, which is a _DECL. Return the
6210 result of the substitution. Issue error and warning messages under
6211 control of COMPLAIN. */
6214 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6216 location_t saved_loc;
6220 /* Set the filename and linenumber to improve error-reporting. */
6221 saved_loc = input_location;
6222 input_location = DECL_SOURCE_LOCATION (t);
6224 switch (TREE_CODE (t))
6228 /* We can get here when processing a member function template,
6229 member class template, and template template parameter of
6230 a template class. */
6231 tree decl = DECL_TEMPLATE_RESULT (t);
6236 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6238 /* Template template parameter is treated here. */
6239 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6240 if (new_type == error_mark_node)
6241 return error_mark_node;
6244 TREE_CHAIN (r) = NULL_TREE;
6245 TREE_TYPE (r) = new_type;
6246 DECL_TEMPLATE_RESULT (r)
6247 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6248 DECL_TEMPLATE_PARMS (r)
6249 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6251 TYPE_NAME (new_type) = r;
6255 /* We might already have an instance of this template.
6256 The ARGS are for the surrounding class type, so the
6257 full args contain the tsubst'd args for the context,
6258 plus the innermost args from the template decl. */
6259 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6260 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6261 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6262 /* Because this is a template, the arguments will still be
6263 dependent, even after substitution. If
6264 PROCESSING_TEMPLATE_DECL is not set, the dependency
6265 predicates will short-circuit. */
6266 ++processing_template_decl;
6267 full_args = tsubst_template_args (tmpl_args, args,
6269 --processing_template_decl;
6270 if (full_args == error_mark_node)
6271 return error_mark_node;
6273 /* tsubst_template_args doesn't copy the vector if
6274 nothing changed. But, *something* should have
6276 gcc_assert (full_args != tmpl_args);
6278 spec = retrieve_specialization (t, full_args,
6279 /*class_specializations_p=*/true);
6280 if (spec != NULL_TREE)
6286 /* Make a new template decl. It will be similar to the
6287 original, but will record the current template arguments.
6288 We also create a new function declaration, which is just
6289 like the old one, but points to this new template, rather
6290 than the old one. */
6292 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6293 TREE_CHAIN (r) = NULL_TREE;
6295 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6297 if (TREE_CODE (decl) == TYPE_DECL)
6300 ++processing_template_decl;
6301 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6302 --processing_template_decl;
6303 if (new_type == error_mark_node)
6304 return error_mark_node;
6306 TREE_TYPE (r) = new_type;
6307 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6308 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6309 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6310 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
6315 ++processing_template_decl;
6316 new_decl = tsubst (decl, args, complain, in_decl);
6317 --processing_template_decl;
6318 if (new_decl == error_mark_node)
6319 return error_mark_node;
6321 DECL_TEMPLATE_RESULT (r) = new_decl;
6322 DECL_TI_TEMPLATE (new_decl) = r;
6323 TREE_TYPE (r) = TREE_TYPE (new_decl);
6324 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6325 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
6328 SET_DECL_IMPLICIT_INSTANTIATION (r);
6329 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6330 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6332 /* The template parameters for this new template are all the
6333 template parameters for the old template, except the
6334 outermost level of parameters. */
6335 DECL_TEMPLATE_PARMS (r)
6336 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6339 if (PRIMARY_TEMPLATE_P (t))
6340 DECL_PRIMARY_TEMPLATE (r) = r;
6342 if (TREE_CODE (decl) != TYPE_DECL)
6343 /* Record this non-type partial instantiation. */
6344 register_specialization (r, t,
6345 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
6353 tree argvec = NULL_TREE;
6361 /* Nobody should be tsubst'ing into non-template functions. */
6362 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6364 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6369 /* If T is not dependent, just return it. We have to
6370 increment PROCESSING_TEMPLATE_DECL because
6371 value_dependent_expression_p assumes that nothing is
6372 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6373 ++processing_template_decl;
6374 dependent_p = value_dependent_expression_p (t);
6375 --processing_template_decl;
6379 /* Calculate the most general template of which R is a
6380 specialization, and the complete set of arguments used to
6382 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6383 argvec = tsubst_template_args (DECL_TI_ARGS
6384 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6385 args, complain, in_decl);
6387 /* Check to see if we already have this specialization. */
6388 spec = retrieve_specialization (gen_tmpl, argvec,
6389 /*class_specializations_p=*/false);
6397 /* We can see more levels of arguments than parameters if
6398 there was a specialization of a member template, like
6401 template <class T> struct S { template <class U> void f(); }
6402 template <> template <class U> void S<int>::f(U);
6404 Here, we'll be substituting into the specialization,
6405 because that's where we can find the code we actually
6406 want to generate, but we'll have enough arguments for
6407 the most general template.
6409 We also deal with the peculiar case:
6411 template <class T> struct S {
6412 template <class U> friend void f();
6414 template <class U> void f() {}
6416 template void f<double>();
6418 Here, the ARGS for the instantiation of will be {int,
6419 double}. But, we only need as many ARGS as there are
6420 levels of template parameters in CODE_PATTERN. We are
6421 careful not to get fooled into reducing the ARGS in
6424 template <class T> struct S { template <class U> void f(U); }
6425 template <class T> template <> void S<T>::f(int) {}
6427 which we can spot because the pattern will be a
6428 specialization in this case. */
6429 args_depth = TMPL_ARGS_DEPTH (args);
6431 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6432 if (args_depth > parms_depth
6433 && !DECL_TEMPLATE_SPECIALIZATION (t))
6434 args = get_innermost_template_args (args, parms_depth);
6438 /* This special case arises when we have something like this:
6440 template <class T> struct S {
6441 friend void f<int>(int, double);
6444 Here, the DECL_TI_TEMPLATE for the friend declaration
6445 will be an IDENTIFIER_NODE. We are being called from
6446 tsubst_friend_function, and we want only to create a
6447 new decl (R) with appropriate types so that we can call
6448 determine_specialization. */
6449 gen_tmpl = NULL_TREE;
6452 if (DECL_CLASS_SCOPE_P (t))
6454 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6458 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6459 complain, t, /*entering_scope=*/1);
6464 ctx = DECL_CONTEXT (t);
6466 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6467 if (type == error_mark_node)
6468 return error_mark_node;
6470 /* We do NOT check for matching decls pushed separately at this
6471 point, as they may not represent instantiations of this
6472 template, and in any case are considered separate under the
6475 DECL_USE_TEMPLATE (r) = 0;
6476 TREE_TYPE (r) = type;
6477 /* Clear out the mangled name and RTL for the instantiation. */
6478 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6479 SET_DECL_RTL (r, NULL_RTX);
6480 DECL_INITIAL (r) = NULL_TREE;
6481 DECL_CONTEXT (r) = ctx;
6483 if (member && DECL_CONV_FN_P (r))
6484 /* Type-conversion operator. Reconstruct the name, in
6485 case it's the name of one of the template's parameters. */
6486 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6488 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6490 DECL_RESULT (r) = NULL_TREE;
6492 TREE_STATIC (r) = 0;
6493 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6494 DECL_EXTERNAL (r) = 1;
6495 /* If this is an instantiation of a function with internal
6496 linkage, we already know what object file linkage will be
6497 assigned to the instantiation. */
6498 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6499 DECL_DEFER_OUTPUT (r) = 0;
6500 TREE_CHAIN (r) = NULL_TREE;
6501 DECL_PENDING_INLINE_INFO (r) = 0;
6502 DECL_PENDING_INLINE_P (r) = 0;
6503 DECL_SAVED_TREE (r) = NULL_TREE;
6505 if (DECL_CLONED_FUNCTION (r))
6507 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6509 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6510 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6513 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6514 this in the special friend case mentioned above where
6515 GEN_TMPL is NULL. */
6518 DECL_TEMPLATE_INFO (r)
6519 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6520 SET_DECL_IMPLICIT_INSTANTIATION (r);
6521 register_specialization (r, gen_tmpl, argvec, false);
6523 /* We're not supposed to instantiate default arguments
6524 until they are called, for a template. But, for a
6527 template <class T> void f ()
6528 { extern void g(int i = T()); }
6530 we should do the substitution when the template is
6531 instantiated. We handle the member function case in
6532 instantiate_class_template since the default arguments
6533 might refer to other members of the class. */
6535 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6536 && !uses_template_parms (argvec))
6537 tsubst_default_arguments (r);
6540 DECL_TEMPLATE_INFO (r) = NULL_TREE;
6542 /* Copy the list of befriending classes. */
6543 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6545 friends = &TREE_CHAIN (*friends))
6547 *friends = copy_node (*friends);
6548 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6553 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6555 maybe_retrofit_in_chrg (r);
6556 if (DECL_CONSTRUCTOR_P (r))
6557 grok_ctor_properties (ctx, r);
6558 /* If this is an instantiation of a member template, clone it.
6559 If it isn't, that'll be handled by
6560 clone_constructors_and_destructors. */
6561 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6562 clone_function_decl (r, /*update_method_vec_p=*/0);
6564 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6565 grok_op_properties (r, (complain & tf_error) != 0);
6567 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6568 SET_DECL_FRIEND_CONTEXT (r,
6569 tsubst (DECL_FRIEND_CONTEXT (t),
6570 args, complain, in_decl));
6579 if (DECL_TEMPLATE_PARM_P (t))
6580 SET_DECL_TEMPLATE_PARM_P (r);
6582 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6583 type = type_decays_to (type);
6584 TREE_TYPE (r) = type;
6585 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6587 if (DECL_INITIAL (r))
6589 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6590 DECL_INITIAL (r) = TREE_TYPE (r);
6592 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6596 DECL_CONTEXT (r) = NULL_TREE;
6598 if (!DECL_TEMPLATE_PARM_P (r))
6599 DECL_ARG_TYPE (r) = type_passed_as (type);
6601 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6602 complain, TREE_CHAIN (t));
6611 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6612 if (type == error_mark_node)
6613 return error_mark_node;
6614 TREE_TYPE (r) = type;
6615 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6617 /* We don't have to set DECL_CONTEXT here; it is set by
6618 finish_member_declaration. */
6619 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6621 TREE_CHAIN (r) = NULL_TREE;
6622 if (VOID_TYPE_P (type))
6623 error ("instantiation of %q+D as type %qT", r, type);
6628 /* We reach here only for member using decls. */
6629 if (DECL_DEPENDENT_P (t))
6631 r = do_class_using_decl
6632 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
6633 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
6635 r = error_mark_node;
6640 TREE_CHAIN (r) = NULL_TREE;
6647 tree argvec = NULL_TREE;
6648 tree gen_tmpl = NULL_TREE;
6650 tree tmpl = NULL_TREE;
6652 tree type = NULL_TREE;
6655 if (TREE_CODE (t) == TYPE_DECL)
6657 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6658 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6659 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6661 /* If this is the canonical decl, we don't have to
6662 mess with instantiations, and often we can't (for
6663 typename, template type parms and such). Note that
6664 TYPE_NAME is not correct for the above test if
6665 we've copied the type for a typedef. */
6666 r = TYPE_NAME (type);
6671 /* Assume this is a non-local variable. */
6674 if (TYPE_P (CP_DECL_CONTEXT (t)))
6675 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6677 in_decl, /*entering_scope=*/1);
6678 else if (DECL_NAMESPACE_SCOPE_P (t))
6679 ctx = DECL_CONTEXT (t);
6682 /* Subsequent calls to pushdecl will fill this in. */
6687 /* Check to see if we already have this specialization. */
6690 tmpl = DECL_TI_TEMPLATE (t);
6691 gen_tmpl = most_general_template (tmpl);
6692 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6693 spec = retrieve_specialization (gen_tmpl, argvec,
6694 /*class_specializations_p=*/false);
6697 spec = retrieve_local_specialization (t);
6706 if (TREE_CODE (r) == VAR_DECL)
6708 /* Even if the original location is out of scope, the
6709 newly substituted one is not. */
6710 DECL_DEAD_FOR_LOCAL (r) = 0;
6711 DECL_INITIALIZED_P (r) = 0;
6712 DECL_TEMPLATE_INSTANTIATED (r) = 0;
6713 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6714 if (type == error_mark_node)
6715 return error_mark_node;
6716 type = complete_type (type);
6717 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6718 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6719 type = check_var_type (DECL_NAME (r), type);
6721 if (DECL_HAS_VALUE_EXPR_P (t))
6723 tree ve = DECL_VALUE_EXPR (t);
6724 ve = tsubst_expr (ve, args, complain, in_decl);
6725 SET_DECL_VALUE_EXPR (r, ve);
6728 else if (DECL_SELF_REFERENCE_P (t))
6729 SET_DECL_SELF_REFERENCE_P (r);
6730 TREE_TYPE (r) = type;
6731 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6732 DECL_CONTEXT (r) = ctx;
6733 /* Clear out the mangled name and RTL for the instantiation. */
6734 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6735 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6736 SET_DECL_RTL (r, NULL_RTX);
6737 /* The initializer must not be expanded until it is required;
6739 DECL_INITIAL (r) = NULL_TREE;
6740 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6741 SET_DECL_RTL (r, NULL_RTX);
6742 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6746 /* A static data member declaration is always marked
6747 external when it is declared in-class, even if an
6748 initializer is present. We mimic the non-template
6750 DECL_EXTERNAL (r) = 1;
6752 register_specialization (r, gen_tmpl, argvec, false);
6753 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6754 SET_DECL_IMPLICIT_INSTANTIATION (r);
6757 register_local_specialization (r, t);
6759 TREE_CHAIN (r) = NULL_TREE;
6768 /* Restore the file and line information. */
6769 input_location = saved_loc;
6774 /* Substitute into the ARG_TYPES of a function type. */
6777 tsubst_arg_types (tree arg_types,
6779 tsubst_flags_t complain,
6782 tree remaining_arg_types;
6785 tree result = NULL_TREE;
6787 if (!arg_types || arg_types == void_list_node)
6790 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6791 args, complain, in_decl);
6792 if (remaining_arg_types == error_mark_node)
6793 return error_mark_node;
6795 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6796 if (type == error_mark_node)
6797 return error_mark_node;
6798 if (VOID_TYPE_P (type))
6800 if (complain & tf_error)
6802 error ("invalid parameter type %qT", type);
6804 error ("in declaration %q+D", in_decl);
6806 return error_mark_node;
6809 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6810 top-level qualifiers as required. */
6811 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6813 /* We do not substitute into default arguments here. The standard
6814 mandates that they be instantiated only when needed, which is
6815 done in build_over_call. */
6816 default_arg = TREE_PURPOSE (arg_types);
6818 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
6820 /* We've instantiated a template before its default arguments
6821 have been parsed. This can happen for a nested template
6822 class, and is not an error unless we require the default
6823 argument in a call of this function. */
6824 result = tree_cons (default_arg, type, remaining_arg_types);
6825 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
6828 result = hash_tree_cons (default_arg, type, remaining_arg_types);
6833 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6834 *not* handle the exception-specification for FNTYPE, because the
6835 initial substitution of explicitly provided template parameters
6836 during argument deduction forbids substitution into the
6837 exception-specification:
6841 All references in the function type of the function template to the
6842 corresponding template parameters are replaced by the specified tem-
6843 plate argument values. If a substitution in a template parameter or
6844 in the function type of the function template results in an invalid
6845 type, type deduction fails. [Note: The equivalent substitution in
6846 exception specifications is done only when the function is instanti-
6847 ated, at which point a program is ill-formed if the substitution
6848 results in an invalid type.] */
6851 tsubst_function_type (tree t,
6853 tsubst_flags_t complain,
6860 /* The TYPE_CONTEXT is not used for function/method types. */
6861 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6863 /* Substitute the return type. */
6864 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6865 if (return_type == error_mark_node)
6866 return error_mark_node;
6867 /* The standard does not presently indicate that creation of a
6868 function type with an invalid return type is a deduction failure.
6869 However, that is clearly analogous to creating an array of "void"
6870 or a reference to a reference. This is core issue #486. */
6871 if (TREE_CODE (return_type) == ARRAY_TYPE
6872 || TREE_CODE (return_type) == FUNCTION_TYPE)
6874 if (complain & tf_error)
6876 if (TREE_CODE (return_type) == ARRAY_TYPE)
6877 error ("function returning an array");
6879 error ("function returning a function");
6881 return error_mark_node;
6884 /* Substitute the argument types. */
6885 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6887 if (arg_types == error_mark_node)
6888 return error_mark_node;
6890 /* Construct a new type node and return it. */
6891 if (TREE_CODE (t) == FUNCTION_TYPE)
6892 fntype = build_function_type (return_type, arg_types);
6895 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6896 if (! IS_AGGR_TYPE (r))
6900 Type deduction may fail for any of the following
6903 -- Attempting to create "pointer to member of T" when T
6904 is not a class type. */
6905 if (complain & tf_error)
6906 error ("creating pointer to member function of non-class type %qT",
6908 return error_mark_node;
6911 fntype = build_method_type_directly (r, return_type,
6912 TREE_CHAIN (arg_types));
6914 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6915 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6920 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6921 ARGS into that specification, and return the substituted
6922 specification. If there is no specification, return NULL_TREE. */
6925 tsubst_exception_specification (tree fntype,
6927 tsubst_flags_t complain,
6933 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6934 new_specs = NULL_TREE;
6937 if (! TREE_VALUE (specs))
6943 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6944 if (spec == error_mark_node)
6946 new_specs = add_exception_specifier (new_specs, spec, complain);
6947 specs = TREE_CHAIN (specs);
6953 /* Take the tree structure T and replace template parameters used
6954 therein with the argument vector ARGS. IN_DECL is an associated
6955 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6956 Issue error and warning messages under control of COMPLAIN. Note
6957 that we must be relatively non-tolerant of extensions here, in
6958 order to preserve conformance; if we allow substitutions that
6959 should not be allowed, we may allow argument deductions that should
6960 not succeed, and therefore report ambiguous overload situations
6961 where there are none. In theory, we could allow the substitution,
6962 but indicate that it should have failed, and allow our caller to
6963 make sure that the right thing happens, but we don't try to do this
6966 This function is used for dealing with types, decls and the like;
6967 for expressions, use tsubst_expr or tsubst_copy. */
6970 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6974 if (t == NULL_TREE || t == error_mark_node
6975 || t == integer_type_node
6976 || t == void_type_node
6977 || t == char_type_node
6978 || t == unknown_type_node
6979 || TREE_CODE (t) == NAMESPACE_DECL)
6983 return tsubst_decl (t, args, complain);
6985 if (TREE_CODE (t) == IDENTIFIER_NODE)
6986 type = IDENTIFIER_TYPE_VALUE (t);
6988 type = TREE_TYPE (t);
6990 gcc_assert (type != unknown_type_node);
6993 && TREE_CODE (t) != TYPENAME_TYPE
6994 && TREE_CODE (t) != IDENTIFIER_NODE
6995 && TREE_CODE (t) != FUNCTION_TYPE
6996 && TREE_CODE (t) != METHOD_TYPE)
6997 type = tsubst (type, args, complain, in_decl);
6998 if (type == error_mark_node)
6999 return error_mark_node;
7001 switch (TREE_CODE (t))
7006 return tsubst_aggr_type (t, args, complain, in_decl,
7007 /*entering_scope=*/0);
7010 case IDENTIFIER_NODE:
7022 if (t == integer_type_node)
7025 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
7026 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
7030 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
7032 /* The array dimension behaves like a non-type template arg,
7033 in that we want to fold it as much as possible. */
7034 max = tsubst_template_arg (omax, args, complain, in_decl);
7035 max = fold_decl_constant_value (max);
7039 Type deduction may fail for any of the following
7042 Attempting to create an array with a size that is
7043 zero or negative. */
7044 if (integer_zerop (max) && !(complain & tf_error))
7045 /* We must fail if performing argument deduction (as
7046 indicated by the state of complain), so that
7047 another substitution can be found. */
7048 return error_mark_node;
7050 else if (TREE_CODE (max) == INTEGER_CST
7051 && INT_CST_LT (max, integer_zero_node))
7053 if (complain & tf_error)
7054 error ("creating array with negative size (%qE)", max);
7056 return error_mark_node;
7059 return compute_array_index_type (NULL_TREE, max);
7062 case TEMPLATE_TYPE_PARM:
7063 case TEMPLATE_TEMPLATE_PARM:
7064 case BOUND_TEMPLATE_TEMPLATE_PARM:
7065 case TEMPLATE_PARM_INDEX:
7070 tree arg = NULL_TREE;
7074 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7075 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7076 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7077 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7079 idx = TEMPLATE_TYPE_IDX (t);
7080 level = TEMPLATE_TYPE_LEVEL (t);
7084 idx = TEMPLATE_PARM_IDX (t);
7085 level = TEMPLATE_PARM_LEVEL (t);
7088 levels = TMPL_ARGS_DEPTH (args);
7089 if (level <= levels)
7090 arg = TMPL_ARG (args, level, idx);
7092 if (arg == error_mark_node)
7093 return error_mark_node;
7094 else if (arg != NULL_TREE)
7096 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7098 gcc_assert (TYPE_P (arg));
7099 return cp_build_qualified_type_real
7100 (arg, cp_type_quals (arg) | cp_type_quals (t),
7101 complain | tf_ignore_bad_quals);
7103 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7105 /* We are processing a type constructed from a
7106 template template parameter. */
7107 tree argvec = tsubst (TYPE_TI_ARGS (t),
7108 args, complain, in_decl);
7109 if (argvec == error_mark_node)
7110 return error_mark_node;
7112 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7113 are resolving nested-types in the signature of a
7114 member function templates. Otherwise ARG is a
7115 TEMPLATE_DECL and is the real template to be
7117 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7118 arg = TYPE_NAME (arg);
7120 r = lookup_template_class (arg,
7123 /*entering_scope=*/0,
7125 return cp_build_qualified_type_real
7126 (r, TYPE_QUALS (t), complain);
7129 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7134 /* This can happen during the attempted tsubst'ing in
7135 unify. This means that we don't yet have any information
7136 about the template parameter in question. */
7139 /* If we get here, we must have been looking at a parm for a
7140 more deeply nested template. Make a new version of this
7141 template parameter, but with a lower level. */
7142 switch (TREE_CODE (t))
7144 case TEMPLATE_TYPE_PARM:
7145 case TEMPLATE_TEMPLATE_PARM:
7146 case BOUND_TEMPLATE_TEMPLATE_PARM:
7147 if (cp_type_quals (t))
7149 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7150 r = cp_build_qualified_type_real
7151 (r, cp_type_quals (t),
7152 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7153 ? tf_ignore_bad_quals : 0));
7158 TEMPLATE_TYPE_PARM_INDEX (r)
7159 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7161 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7162 TYPE_MAIN_VARIANT (r) = r;
7163 TYPE_POINTER_TO (r) = NULL_TREE;
7164 TYPE_REFERENCE_TO (r) = NULL_TREE;
7166 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7168 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7170 if (argvec == error_mark_node)
7171 return error_mark_node;
7173 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7174 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7179 case TEMPLATE_PARM_INDEX:
7180 r = reduce_template_parm_level (t, type, levels);
7192 tree purpose, value, chain;
7194 if (t == void_list_node)
7197 purpose = TREE_PURPOSE (t);
7200 purpose = tsubst (purpose, args, complain, in_decl);
7201 if (purpose == error_mark_node)
7202 return error_mark_node;
7204 value = TREE_VALUE (t);
7207 value = tsubst (value, args, complain, in_decl);
7208 if (value == error_mark_node)
7209 return error_mark_node;
7211 chain = TREE_CHAIN (t);
7212 if (chain && chain != void_type_node)
7214 chain = tsubst (chain, args, complain, in_decl);
7215 if (chain == error_mark_node)
7216 return error_mark_node;
7218 if (purpose == TREE_PURPOSE (t)
7219 && value == TREE_VALUE (t)
7220 && chain == TREE_CHAIN (t))
7222 return hash_tree_cons (purpose, value, chain);
7226 /* We should never be tsubsting a binfo. */
7230 /* A vector of template arguments. */
7232 return tsubst_template_args (t, args, complain, in_decl);
7235 case REFERENCE_TYPE:
7237 enum tree_code code;
7239 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7242 code = TREE_CODE (t);
7247 Type deduction may fail for any of the following
7250 -- Attempting to create a pointer to reference type.
7251 -- Attempting to create a reference to a reference type or
7252 a reference to void. */
7253 if (TREE_CODE (type) == REFERENCE_TYPE
7254 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7256 static location_t last_loc;
7258 /* We keep track of the last time we issued this error
7259 message to avoid spewing a ton of messages during a
7260 single bad template instantiation. */
7261 if (complain & tf_error
7262 #ifdef USE_MAPPED_LOCATION
7263 && last_loc != input_location
7265 && (last_loc.line != input_line
7266 || last_loc.file != input_filename)
7270 if (TREE_CODE (type) == VOID_TYPE)
7271 error ("forming reference to void");
7273 error ("forming %s to reference type %qT",
7274 (code == POINTER_TYPE) ? "pointer" : "reference",
7276 last_loc = input_location;
7279 return error_mark_node;
7281 else if (code == POINTER_TYPE)
7283 r = build_pointer_type (type);
7284 if (TREE_CODE (type) == METHOD_TYPE)
7285 r = build_ptrmemfunc_type (r);
7288 r = build_reference_type (type);
7289 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7291 if (r != error_mark_node)
7292 /* Will this ever be needed for TYPE_..._TO values? */
7299 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7300 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7304 Type deduction may fail for any of the following
7307 -- Attempting to create "pointer to member of T" when T
7308 is not a class type. */
7309 if (complain & tf_error)
7310 error ("creating pointer to member of non-class type %qT", r);
7311 return error_mark_node;
7313 if (TREE_CODE (type) == REFERENCE_TYPE)
7315 if (complain & tf_error)
7316 error ("creating pointer to member reference type %qT", type);
7317 return error_mark_node;
7319 if (TREE_CODE (type) == VOID_TYPE)
7321 if (complain & tf_error)
7322 error ("creating pointer to member of type void");
7323 return error_mark_node;
7325 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7326 if (TREE_CODE (type) == FUNCTION_TYPE)
7328 /* The type of the implicit object parameter gets its
7329 cv-qualifiers from the FUNCTION_TYPE. */
7331 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7332 cp_type_quals (type));
7334 method_type = build_method_type_directly (this_type,
7336 TYPE_ARG_TYPES (type));
7337 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7338 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7342 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7351 fntype = tsubst_function_type (t, args, complain, in_decl);
7352 if (fntype == error_mark_node)
7353 return error_mark_node;
7355 /* Substitute the exception specification. */
7356 specs = tsubst_exception_specification (t, args, complain,
7358 if (specs == error_mark_node)
7359 return error_mark_node;
7361 fntype = build_exception_variant (fntype, specs);
7366 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7367 if (domain == error_mark_node)
7368 return error_mark_node;
7370 /* As an optimization, we avoid regenerating the array type if
7371 it will obviously be the same as T. */
7372 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7375 /* These checks should match the ones in grokdeclarator.
7379 The deduction may fail for any of the following reasons:
7381 -- Attempting to create an array with an element type that
7382 is void, a function type, or a reference type, or [DR337]
7383 an abstract class type. */
7384 if (TREE_CODE (type) == VOID_TYPE
7385 || TREE_CODE (type) == FUNCTION_TYPE
7386 || TREE_CODE (type) == REFERENCE_TYPE)
7388 if (complain & tf_error)
7389 error ("creating array of %qT", type);
7390 return error_mark_node;
7392 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7394 if (complain & tf_error)
7395 error ("creating array of %qT, which is an abstract class type",
7397 return error_mark_node;
7400 r = build_cplus_array_type (type, domain);
7407 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7408 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7410 if (e1 == error_mark_node || e2 == error_mark_node)
7411 return error_mark_node;
7413 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7419 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7420 if (e == error_mark_node)
7421 return error_mark_node;
7423 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7428 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7429 in_decl, /*entering_scope=*/1);
7430 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7433 if (ctx == error_mark_node || f == error_mark_node)
7434 return error_mark_node;
7436 if (!IS_AGGR_TYPE (ctx))
7438 if (complain & tf_error)
7439 error ("%qT is not a class, struct, or union type", ctx);
7440 return error_mark_node;
7442 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7444 /* Normally, make_typename_type does not require that the CTX
7445 have complete type in order to allow things like:
7447 template <class T> struct S { typename S<T>::X Y; };
7449 But, such constructs have already been resolved by this
7450 point, so here CTX really should have complete type, unless
7451 it's a partial instantiation. */
7452 ctx = complete_type (ctx);
7453 if (!COMPLETE_TYPE_P (ctx))
7455 if (complain & tf_error)
7456 cxx_incomplete_type_error (NULL_TREE, ctx);
7457 return error_mark_node;
7461 f = make_typename_type (ctx, f, typename_type,
7462 (complain & tf_error) | tf_keep_type_decl);
7463 if (f == error_mark_node)
7465 if (TREE_CODE (f) == TYPE_DECL)
7467 complain |= tf_ignore_bad_quals;
7471 if (TREE_CODE (f) != TYPENAME_TYPE)
7473 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7474 error ("%qT resolves to %qT, which is not an enumeration type",
7476 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7477 error ("%qT resolves to %qT, which is is not a class type",
7481 return cp_build_qualified_type_real
7482 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7485 case UNBOUND_CLASS_TEMPLATE:
7487 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7488 in_decl, /*entering_scope=*/1);
7489 tree name = TYPE_IDENTIFIER (t);
7490 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7492 if (ctx == error_mark_node || name == error_mark_node)
7493 return error_mark_node;
7496 parm_list = tsubst_template_parms (parm_list, args, complain);
7497 return make_unbound_class_template (ctx, name, parm_list, complain);
7507 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7508 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7509 if (e1 == error_mark_node || e2 == error_mark_node)
7510 return error_mark_node;
7512 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7517 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7518 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7519 if (e1 == error_mark_node || e2 == error_mark_node)
7520 return error_mark_node;
7522 return build_qualified_name (/*type=*/NULL_TREE,
7523 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
7530 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7531 complain, in_decl));
7532 return cp_build_qualified_type_real (type,
7534 | cp_type_quals (type),
7539 sorry ("use of %qs in template",
7540 tree_code_name [(int) TREE_CODE (t)]);
7541 return error_mark_node;
7545 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7546 type of the expression on the left-hand side of the "." or "->"
7550 tsubst_baselink (tree baselink, tree object_type,
7551 tree args, tsubst_flags_t complain, tree in_decl)
7554 tree qualifying_scope;
7556 tree template_args = 0;
7557 bool template_id_p = false;
7559 /* A baselink indicates a function from a base class. The
7560 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7561 non-dependent types; otherwise, the lookup could not have
7562 succeeded. However, they may indicate bases of the template
7563 class, rather than the instantiated class.
7565 In addition, lookups that were not ambiguous before may be
7566 ambiguous now. Therefore, we perform the lookup again. */
7567 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7568 fns = BASELINK_FUNCTIONS (baselink);
7569 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7571 template_id_p = true;
7572 template_args = TREE_OPERAND (fns, 1);
7573 fns = TREE_OPERAND (fns, 0);
7575 template_args = tsubst_template_args (template_args, args,
7578 name = DECL_NAME (get_first_fn (fns));
7579 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7581 /* If lookup found a single function, mark it as used at this
7582 point. (If it lookup found multiple functions the one selected
7583 later by overload resolution will be marked as used at that
7585 if (BASELINK_P (baselink))
7586 fns = BASELINK_FUNCTIONS (baselink);
7587 if (!template_id_p && !really_overloaded_fn (fns))
7588 mark_used (OVL_CURRENT (fns));
7590 /* Add back the template arguments, if present. */
7591 if (BASELINK_P (baselink) && template_id_p)
7592 BASELINK_FUNCTIONS (baselink)
7593 = build_nt (TEMPLATE_ID_EXPR,
7594 BASELINK_FUNCTIONS (baselink),
7598 object_type = current_class_type;
7599 return adjust_result_of_qualified_name_lookup (baselink,
7604 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7605 true if the qualified-id will be a postfix-expression in-and-of
7606 itself; false if more of the postfix-expression follows the
7607 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7611 tsubst_qualified_id (tree qualified_id, tree args,
7612 tsubst_flags_t complain, tree in_decl,
7613 bool done, bool address_p)
7621 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7623 /* Figure out what name to look up. */
7624 name = TREE_OPERAND (qualified_id, 1);
7625 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7628 template_args = TREE_OPERAND (name, 1);
7630 template_args = tsubst_template_args (template_args, args,
7632 name = TREE_OPERAND (name, 0);
7636 is_template = false;
7637 template_args = NULL_TREE;
7640 /* Substitute into the qualifying scope. When there are no ARGS, we
7641 are just trying to simplify a non-dependent expression. In that
7642 case the qualifying scope may be dependent, and, in any case,
7643 substituting will not help. */
7644 scope = TREE_OPERAND (qualified_id, 0);
7647 scope = tsubst (scope, args, complain, in_decl);
7648 expr = tsubst_copy (name, args, complain, in_decl);
7653 if (dependent_type_p (scope))
7654 return build_qualified_name (/*type=*/NULL_TREE,
7656 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
7658 if (!BASELINK_P (name) && !DECL_P (expr))
7660 if (TREE_CODE (expr) == BIT_NOT_EXPR)
7661 /* If this were actually a destructor call, it would have been
7662 parsed as such by the parser. */
7663 expr = error_mark_node;
7665 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7666 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7667 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7669 if (complain & tf_error)
7671 error ("dependent-name %qE is parsed as a non-type, but "
7672 "instantiation yields a type", qualified_id);
7673 inform ("say %<typename %E%> if a type is meant", qualified_id);
7675 return error_mark_node;
7681 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7683 /* Remember that there was a reference to this entity. */
7687 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7689 if (complain & tf_error)
7690 qualified_name_lookup_error (scope,
7691 TREE_OPERAND (qualified_id, 1),
7693 return error_mark_node;
7697 expr = lookup_template_function (expr, template_args);
7699 if (expr == error_mark_node && complain & tf_error)
7700 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7702 else if (TYPE_P (scope))
7704 expr = (adjust_result_of_qualified_name_lookup
7705 (expr, scope, current_class_type));
7706 expr = (finish_qualified_id_expr
7707 (scope, expr, done, address_p,
7708 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
7709 /*template_arg_p=*/false));
7712 if (TREE_CODE (expr) != SCOPE_REF)
7713 expr = convert_from_reference (expr);
7718 /* Like tsubst, but deals with expressions. This function just replaces
7719 template parms; to finish processing the resultant expression, use
7723 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7725 enum tree_code code;
7728 if (t == NULL_TREE || t == error_mark_node)
7731 code = TREE_CODE (t);
7736 r = retrieve_local_specialization (t);
7737 gcc_assert (r != NULL);
7746 if (DECL_TEMPLATE_PARM_P (t))
7747 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7748 /* There is no need to substitute into namespace-scope
7750 if (DECL_NAMESPACE_SCOPE_P (t))
7752 /* If ARGS is NULL, then T is known to be non-dependent. */
7753 if (args == NULL_TREE)
7754 return integral_constant_value (t);
7756 /* Unfortunately, we cannot just call lookup_name here.
7759 template <int I> int f() {
7761 struct S { void g() { E e = a; } };
7764 When we instantiate f<7>::S::g(), say, lookup_name is not
7765 clever enough to find f<7>::a. */
7767 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7768 /*entering_scope=*/0);
7770 for (v = TYPE_VALUES (enum_type);
7773 if (TREE_PURPOSE (v) == DECL_NAME (t))
7774 return TREE_VALUE (v);
7776 /* We didn't find the name. That should never happen; if
7777 name-lookup found it during preliminary parsing, we
7778 should find it again here during instantiation. */
7784 if (DECL_CONTEXT (t))
7788 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7789 /*entering_scope=*/1);
7790 if (ctx != DECL_CONTEXT (t))
7792 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7795 if (complain & tf_error)
7796 error ("using invalid field %qD", t);
7797 return error_mark_node;
7807 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7808 || local_variable_p (t))
7809 t = tsubst (t, args, complain, in_decl);
7814 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7817 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7818 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7819 args, complain, in_decl);
7820 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7821 return tsubst (t, args, complain, in_decl);
7822 else if (DECL_CLASS_SCOPE_P (t)
7823 && uses_template_parms (DECL_CONTEXT (t)))
7825 /* Template template argument like the following example need
7828 template <template <class> class TT> struct C {};
7829 template <class T> struct D {
7830 template <class U> struct E {};
7835 We are processing the template argument `E' in #1 for
7836 the template instantiation #2. Originally, `E' is a
7837 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7838 have to substitute this with one having context `D<int>'. */
7840 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7841 return lookup_field (context, DECL_NAME(t), 0, false);
7844 /* Ordinary template template argument. */
7848 case REINTERPRET_CAST_EXPR:
7849 case CONST_CAST_EXPR:
7850 case STATIC_CAST_EXPR:
7851 case DYNAMIC_CAST_EXPR:
7854 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7855 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7859 case TRUTH_NOT_EXPR:
7862 case UNARY_PLUS_EXPR: /* Unary + */
7871 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7872 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7879 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7880 name = TREE_OPERAND (t, 1);
7881 if (TREE_CODE (name) == BIT_NOT_EXPR)
7883 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7885 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7887 else if (TREE_CODE (name) == SCOPE_REF
7888 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7890 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7892 name = TREE_OPERAND (name, 1);
7893 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7895 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7896 name = build_qualified_name (/*type=*/NULL_TREE,
7898 /*template_p=*/false);
7900 else if (TREE_CODE (name) == BASELINK)
7901 name = tsubst_baselink (name,
7902 non_reference (TREE_TYPE (object)),
7906 name = tsubst_copy (name, args, complain, in_decl);
7907 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7913 case TRUNC_DIV_EXPR:
7915 case FLOOR_DIV_EXPR:
7916 case ROUND_DIV_EXPR:
7917 case EXACT_DIV_EXPR:
7921 case TRUNC_MOD_EXPR:
7922 case FLOOR_MOD_EXPR:
7923 case TRUTH_ANDIF_EXPR:
7924 case TRUTH_ORIF_EXPR:
7925 case TRUTH_AND_EXPR:
7942 case PREDECREMENT_EXPR:
7943 case PREINCREMENT_EXPR:
7944 case POSTDECREMENT_EXPR:
7945 case POSTINCREMENT_EXPR:
7947 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7948 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7951 return build_qualified_name (/*type=*/NULL_TREE,
7952 tsubst_copy (TREE_OPERAND (t, 0),
7953 args, complain, in_decl),
7954 tsubst_copy (TREE_OPERAND (t, 1),
7955 args, complain, in_decl),
7956 QUALIFIED_NAME_IS_TEMPLATE (t));
7961 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7962 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7963 NULL_TREE, NULL_TREE);
7966 return build_nt (code,
7967 tsubst_copy (TREE_OPERAND (t, 0), args,
7969 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7975 case PSEUDO_DTOR_EXPR:
7978 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7979 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7980 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7981 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7988 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7989 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7990 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7991 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7998 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7999 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
8000 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
8001 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
8005 case TEMPLATE_ID_EXPR:
8007 /* Substituted template arguments */
8008 tree fn = TREE_OPERAND (t, 0);
8009 tree targs = TREE_OPERAND (t, 1);
8011 fn = tsubst_copy (fn, args, complain, in_decl);
8013 targs = tsubst_template_args (targs, args, complain, in_decl);
8015 return lookup_template_function (fn, targs);
8020 tree purpose, value, chain;
8022 if (t == void_list_node)
8025 purpose = TREE_PURPOSE (t);
8027 purpose = tsubst_copy (purpose, args, complain, in_decl);
8028 value = TREE_VALUE (t);
8030 value = tsubst_copy (value, args, complain, in_decl);
8031 chain = TREE_CHAIN (t);
8032 if (chain && chain != void_type_node)
8033 chain = tsubst_copy (chain, args, complain, in_decl);
8034 if (purpose == TREE_PURPOSE (t)
8035 && value == TREE_VALUE (t)
8036 && chain == TREE_CHAIN (t))
8038 return tree_cons (purpose, value, chain);
8045 case TEMPLATE_TYPE_PARM:
8046 case TEMPLATE_TEMPLATE_PARM:
8047 case BOUND_TEMPLATE_TEMPLATE_PARM:
8048 case TEMPLATE_PARM_INDEX:
8050 case REFERENCE_TYPE:
8056 case UNBOUND_CLASS_TEMPLATE:
8059 return tsubst (t, args, complain, in_decl);
8061 case IDENTIFIER_NODE:
8062 if (IDENTIFIER_TYPENAME_P (t))
8064 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8065 return mangle_conv_op_name_for_type (new_type);
8071 /* This is handled by tsubst_copy_and_build. */
8075 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8077 tsubst (TREE_TYPE (t), args, complain, in_decl));
8079 case CLEANUP_POINT_EXPR:
8080 /* We shouldn't have built any of these during initial template
8081 generation. Instead, they should be built during instantiation
8082 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8086 mark_used (TREE_OPERAND (t, 1));
8094 /* Like tsubst_copy, but specifically for OpenMP clauses. */
8097 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
8100 tree new_clauses = NULL, nc, oc;
8102 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
8104 nc = copy_node (oc);
8105 OMP_CLAUSE_CHAIN (nc) = new_clauses;
8108 switch (OMP_CLAUSE_CODE (nc))
8110 case OMP_CLAUSE_PRIVATE:
8111 case OMP_CLAUSE_SHARED:
8112 case OMP_CLAUSE_FIRSTPRIVATE:
8113 case OMP_CLAUSE_LASTPRIVATE:
8114 case OMP_CLAUSE_REDUCTION:
8115 case OMP_CLAUSE_COPYIN:
8116 case OMP_CLAUSE_COPYPRIVATE:
8118 case OMP_CLAUSE_NUM_THREADS:
8119 case OMP_CLAUSE_SCHEDULE:
8120 OMP_CLAUSE_OPERAND (nc, 0)
8121 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain, in_decl);
8123 case OMP_CLAUSE_NOWAIT:
8124 case OMP_CLAUSE_ORDERED:
8125 case OMP_CLAUSE_DEFAULT:
8132 return finish_omp_clauses (nreverse (new_clauses));
8135 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
8138 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
8141 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
8143 tree purpose, value, chain;
8148 if (TREE_CODE (t) != TREE_LIST)
8149 return tsubst_copy_and_build (t, args, complain, in_decl,
8150 /*function_p=*/false);
8152 if (t == void_list_node)
8155 purpose = TREE_PURPOSE (t);
8157 purpose = RECUR (purpose);
8158 value = TREE_VALUE (t);
8160 value = RECUR (value);
8161 chain = TREE_CHAIN (t);
8162 if (chain && chain != void_type_node)
8163 chain = RECUR (chain);
8164 return tree_cons (purpose, value, chain);
8168 /* Like tsubst_copy for expressions, etc. but also does semantic
8172 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8176 if (t == NULL_TREE || t == error_mark_node)
8179 if (EXPR_HAS_LOCATION (t))
8180 input_location = EXPR_LOCATION (t);
8181 if (STATEMENT_CODE_P (TREE_CODE (t)))
8182 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8184 switch (TREE_CODE (t))
8186 case STATEMENT_LIST:
8188 tree_stmt_iterator i;
8189 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8190 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8194 case CTOR_INITIALIZER:
8195 finish_mem_initializers (tsubst_initializer_list
8196 (TREE_OPERAND (t, 0), args));
8200 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8201 args, complain, in_decl));
8205 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8206 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8207 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8209 finish_expr_stmt (tmp);
8213 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8214 args, complain, in_decl));
8222 decl = DECL_EXPR_DECL (t);
8223 if (TREE_CODE (decl) == LABEL_DECL)
8224 finish_label_decl (DECL_NAME (decl));
8225 else if (TREE_CODE (decl) == USING_DECL)
8227 tree scope = USING_DECL_SCOPE (decl);
8228 tree name = DECL_NAME (decl);
8231 scope = tsubst_expr (scope, args, complain, in_decl);
8232 decl = lookup_qualified_name (scope, name,
8233 /*is_type_p=*/false,
8234 /*complain=*/false);
8235 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8236 qualified_name_lookup_error (scope, name, decl);
8238 do_local_using_decl (decl, scope, name);
8242 init = DECL_INITIAL (decl);
8243 decl = tsubst (decl, args, complain, in_decl);
8244 if (decl != error_mark_node)
8247 DECL_INITIAL (decl) = error_mark_node;
8248 /* By marking the declaration as instantiated, we avoid
8249 trying to instantiate it. Since instantiate_decl can't
8250 handle local variables, and since we've already done
8251 all that needs to be done, that's the right thing to
8253 if (TREE_CODE (decl) == VAR_DECL)
8254 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8255 if (TREE_CODE (decl) == VAR_DECL
8256 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8257 /* Anonymous aggregates are a special case. */
8258 finish_anon_union (decl);
8261 maybe_push_decl (decl);
8262 if (TREE_CODE (decl) == VAR_DECL
8263 && DECL_PRETTY_FUNCTION_P (decl))
8265 /* For __PRETTY_FUNCTION__ we have to adjust the
8267 const char *const name
8268 = cxx_printable_name (current_function_decl, 2);
8269 init = cp_fname_init (name, &TREE_TYPE (decl));
8272 init = tsubst_expr (init, args, complain, in_decl);
8273 finish_decl (decl, init, NULL_TREE);
8278 /* A DECL_EXPR can also be used as an expression, in the condition
8279 clause of an if/for/while construct. */
8284 stmt = begin_for_stmt ();
8285 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8286 finish_for_init_stmt (stmt);
8287 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8288 finish_for_cond (tmp, stmt);
8289 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8290 finish_for_expr (tmp, stmt);
8291 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8292 finish_for_stmt (stmt);
8296 stmt = begin_while_stmt ();
8297 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8298 finish_while_stmt_cond (tmp, stmt);
8299 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8300 finish_while_stmt (stmt);
8304 stmt = begin_do_stmt ();
8305 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8306 finish_do_body (stmt);
8307 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8308 finish_do_stmt (tmp, stmt);
8312 stmt = begin_if_stmt ();
8313 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8314 finish_if_stmt_cond (tmp, stmt);
8315 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8316 finish_then_clause (stmt);
8318 if (ELSE_CLAUSE (t))
8320 begin_else_clause (stmt);
8321 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8322 finish_else_clause (stmt);
8325 finish_if_stmt (stmt);
8329 if (BIND_EXPR_BODY_BLOCK (t))
8330 stmt = begin_function_body ();
8332 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8333 ? BCS_TRY_BLOCK : 0);
8335 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8337 if (BIND_EXPR_BODY_BLOCK (t))
8338 finish_function_body (stmt);
8340 finish_compound_stmt (stmt);
8344 finish_break_stmt ();
8348 finish_continue_stmt ();
8352 stmt = begin_switch_stmt ();
8353 tmp = tsubst_expr (SWITCH_STMT_COND (t), args, complain, in_decl);
8354 finish_switch_cond (tmp, stmt);
8355 tsubst_expr (SWITCH_STMT_BODY (t), args, complain, in_decl);
8356 finish_switch_stmt (stmt);
8359 case CASE_LABEL_EXPR:
8360 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8361 tsubst_expr (CASE_HIGH (t), args, complain,
8366 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8370 tmp = GOTO_DESTINATION (t);
8371 if (TREE_CODE (tmp) != LABEL_DECL)
8372 /* Computed goto's must be tsubst'd into. On the other hand,
8373 non-computed gotos must not be; the identifier in question
8374 will have no binding. */
8375 tmp = tsubst_expr (tmp, args, complain, in_decl);
8377 tmp = DECL_NAME (tmp);
8378 finish_goto_stmt (tmp);
8382 tmp = finish_asm_stmt
8383 (ASM_VOLATILE_P (t),
8384 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8385 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
8386 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
8387 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl));
8389 tree asm_expr = tmp;
8390 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8391 asm_expr = TREE_OPERAND (asm_expr, 0);
8392 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8399 stmt = begin_try_block ();
8400 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8401 finish_cleanup_try_block (stmt);
8402 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8408 if (FN_TRY_BLOCK_P (t))
8409 stmt = begin_function_try_block ();
8411 stmt = begin_try_block ();
8413 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8415 if (FN_TRY_BLOCK_P (t))
8416 finish_function_try_block (stmt);
8418 finish_try_block (stmt);
8420 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8421 if (FN_TRY_BLOCK_P (t))
8422 finish_function_handler_sequence (stmt);
8424 finish_handler_sequence (stmt);
8432 stmt = begin_handler ();
8433 if (HANDLER_PARMS (t))
8435 decl = HANDLER_PARMS (t);
8436 decl = tsubst (decl, args, complain, in_decl);
8437 /* Prevent instantiate_decl from trying to instantiate
8438 this variable. We've already done all that needs to be
8440 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8444 finish_handler_parms (decl, stmt);
8445 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8446 finish_handler (stmt);
8451 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8455 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
8456 args, complain, in_decl);
8457 stmt = begin_omp_parallel ();
8458 tsubst_expr (OMP_PARALLEL_BODY (t), args, complain, in_decl);
8459 finish_omp_parallel (tmp, stmt);
8464 tree clauses, decl, init, cond, incr, body, pre_body;
8466 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
8467 args, complain, in_decl);
8468 init = OMP_FOR_INIT (t);
8469 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
8470 decl = tsubst_expr (TREE_OPERAND (init, 0), args, complain, in_decl);
8471 init = tsubst_expr (TREE_OPERAND (init, 1), args, complain, in_decl);
8472 cond = tsubst_expr (OMP_FOR_COND (t), args, complain, in_decl);
8473 incr = tsubst_expr (OMP_FOR_INCR (t), args, complain, in_decl);
8475 stmt = begin_omp_structured_block ();
8477 pre_body = push_stmt_list ();
8478 tsubst_expr (OMP_FOR_PRE_BODY (t), args, complain, in_decl);
8479 pre_body = pop_stmt_list (pre_body);
8481 body = push_stmt_list ();
8482 tsubst_expr (OMP_FOR_BODY (t), args, complain, in_decl);
8483 body = pop_stmt_list (body);
8485 t = finish_omp_for (EXPR_LOCATION (t), decl, init, cond, incr, body,
8488 OMP_FOR_CLAUSES (t) = clauses;
8490 add_stmt (finish_omp_structured_block (stmt));
8496 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
8497 stmt = push_stmt_list ();
8498 tsubst_expr (OMP_BODY (t), args, complain, in_decl);
8499 stmt = pop_stmt_list (stmt);
8502 OMP_BODY (t) = stmt;
8503 OMP_CLAUSES (t) = tmp;
8511 stmt = push_stmt_list ();
8512 tsubst_expr (OMP_BODY (t), args, complain, in_decl);
8513 stmt = pop_stmt_list (stmt);
8516 OMP_BODY (t) = stmt;
8523 op0 = tsubst_expr (TREE_OPERAND (t, 0), args, complain, in_decl);
8524 op1 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
8525 if (OMP_ATOMIC_DEPENDENT_P (t))
8526 c_finish_omp_atomic (OMP_ATOMIC_CODE (t), op0, op1);
8528 add_stmt (build2 (OMP_ATOMIC, void_type_node, op0, op1));
8533 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8535 return tsubst_copy_and_build (t, args, complain, in_decl,
8536 /*function_p=*/false);
8542 /* T is a postfix-expression that is not being used in a function
8543 call. Return the substituted version of T. */
8546 tsubst_non_call_postfix_expression (tree t, tree args,
8547 tsubst_flags_t complain,
8550 if (TREE_CODE (t) == SCOPE_REF)
8551 t = tsubst_qualified_id (t, args, complain, in_decl,
8552 /*done=*/false, /*address_p=*/false);
8554 t = tsubst_copy_and_build (t, args, complain, in_decl,
8555 /*function_p=*/false);
8560 /* Like tsubst but deals with expressions and performs semantic
8561 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8564 tsubst_copy_and_build (tree t,
8566 tsubst_flags_t complain,
8570 #define RECUR(NODE) \
8571 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8575 if (t == NULL_TREE || t == error_mark_node)
8578 switch (TREE_CODE (t))
8583 case IDENTIFIER_NODE:
8587 bool non_integral_constant_expression_p;
8588 const char *error_msg;
8590 if (IDENTIFIER_TYPENAME_P (t))
8592 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8593 t = mangle_conv_op_name_for_type (new_type);
8596 /* Look up the name. */
8597 decl = lookup_name (t);
8599 /* By convention, expressions use ERROR_MARK_NODE to indicate
8600 failure, not NULL_TREE. */
8601 if (decl == NULL_TREE)
8602 decl = error_mark_node;
8604 decl = finish_id_expression (t, decl, NULL_TREE,
8606 /*integral_constant_expression_p=*/false,
8607 /*allow_non_integral_constant_expression_p=*/false,
8608 &non_integral_constant_expression_p,
8609 /*template_p=*/false,
8611 /*address_p=*/false,
8612 /*template_arg_p=*/false,
8616 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8617 decl = unqualified_name_lookup_error (decl);
8621 case TEMPLATE_ID_EXPR:
8624 tree template = RECUR (TREE_OPERAND (t, 0));
8625 tree targs = TREE_OPERAND (t, 1);
8628 targs = tsubst_template_args (targs, args, complain, in_decl);
8630 if (TREE_CODE (template) == COMPONENT_REF)
8632 object = TREE_OPERAND (template, 0);
8633 template = TREE_OPERAND (template, 1);
8637 template = lookup_template_function (template, targs);
8640 return build3 (COMPONENT_REF, TREE_TYPE (template),
8641 object, template, NULL_TREE);
8648 tree r = RECUR (TREE_OPERAND (t, 0));
8650 if (REFERENCE_REF_P (t))
8652 /* A type conversion to reference type will be enclosed in
8653 such an indirect ref, but the substitution of the cast
8654 will have also added such an indirect ref. */
8655 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8656 r = convert_from_reference (r);
8659 r = build_x_indirect_ref (r, "unary *");
8665 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8666 RECUR (TREE_OPERAND (t, 0)));
8669 return build_functional_cast
8670 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8671 RECUR (TREE_OPERAND (t, 0)));
8673 case REINTERPRET_CAST_EXPR:
8674 return build_reinterpret_cast
8675 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8676 RECUR (TREE_OPERAND (t, 0)));
8678 case CONST_CAST_EXPR:
8679 return build_const_cast
8680 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8681 RECUR (TREE_OPERAND (t, 0)));
8683 case DYNAMIC_CAST_EXPR:
8684 return build_dynamic_cast
8685 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8686 RECUR (TREE_OPERAND (t, 0)));
8688 case STATIC_CAST_EXPR:
8689 return build_static_cast
8690 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8691 RECUR (TREE_OPERAND (t, 0)));
8693 case POSTDECREMENT_EXPR:
8694 case POSTINCREMENT_EXPR:
8695 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8696 args, complain, in_decl);
8697 return build_x_unary_op (TREE_CODE (t), op1);
8699 case PREDECREMENT_EXPR:
8700 case PREINCREMENT_EXPR:
8704 case TRUTH_NOT_EXPR:
8705 case UNARY_PLUS_EXPR: /* Unary + */
8708 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8711 op1 = TREE_OPERAND (t, 0);
8712 if (TREE_CODE (op1) == SCOPE_REF)
8713 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8714 /*done=*/true, /*address_p=*/true);
8716 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8718 if (TREE_CODE (op1) == LABEL_DECL)
8719 return finish_label_address_expr (DECL_NAME (op1));
8720 return build_x_unary_op (ADDR_EXPR, op1);
8725 case TRUNC_DIV_EXPR:
8727 case FLOOR_DIV_EXPR:
8728 case ROUND_DIV_EXPR:
8729 case EXACT_DIV_EXPR:
8733 case TRUNC_MOD_EXPR:
8734 case FLOOR_MOD_EXPR:
8735 case TRUTH_ANDIF_EXPR:
8736 case TRUTH_ORIF_EXPR:
8737 case TRUTH_AND_EXPR:
8753 return build_x_binary_op
8755 RECUR (TREE_OPERAND (t, 0)),
8756 RECUR (TREE_OPERAND (t, 1)),
8757 /*overloaded_p=*/NULL);
8760 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8761 /*address_p=*/false);
8763 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8764 args, complain, in_decl);
8765 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8766 /*overloaded_p=*/NULL);
8770 op1 = TREE_OPERAND (t, 0);
8773 /* When there are no ARGS, we are trying to evaluate a
8774 non-dependent expression from the parser. Trying to do
8775 the substitutions may not work. */
8777 op1 = TREE_TYPE (op1);
8786 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8788 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8792 tree r = build_x_modify_expr
8793 (RECUR (TREE_OPERAND (t, 0)),
8794 TREE_CODE (TREE_OPERAND (t, 1)),
8795 RECUR (TREE_OPERAND (t, 2)));
8796 /* TREE_NO_WARNING must be set if either the expression was
8797 parenthesized or it uses an operator such as >>= rather
8798 than plain assignment. In the former case, it was already
8799 set and must be copied. In the latter case,
8800 build_x_modify_expr sets it and it must not be reset
8802 if (TREE_NO_WARNING (t))
8803 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8808 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8809 args, complain, in_decl);
8810 /* Remember that there was a reference to this entity. */
8813 return build_x_arrow (op1);
8817 (RECUR (TREE_OPERAND (t, 0)),
8818 RECUR (TREE_OPERAND (t, 1)),
8819 RECUR (TREE_OPERAND (t, 2)),
8820 RECUR (TREE_OPERAND (t, 3)),
8821 NEW_EXPR_USE_GLOBAL (t));
8824 return delete_sanity
8825 (RECUR (TREE_OPERAND (t, 0)),
8826 RECUR (TREE_OPERAND (t, 1)),
8827 DELETE_EXPR_USE_VEC (t),
8828 DELETE_EXPR_USE_GLOBAL (t));
8831 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8832 RECUR (TREE_OPERAND (t, 1)));
8841 function = TREE_OPERAND (t, 0);
8842 /* When we parsed the expression, we determined whether or
8843 not Koenig lookup should be performed. */
8844 koenig_p = KOENIG_LOOKUP_P (t);
8845 if (TREE_CODE (function) == SCOPE_REF)
8848 function = tsubst_qualified_id (function, args, complain, in_decl,
8850 /*address_p=*/false);
8854 if (TREE_CODE (function) == COMPONENT_REF)
8856 tree op = TREE_OPERAND (function, 1);
8858 qualified_p = (TREE_CODE (op) == SCOPE_REF
8860 && BASELINK_QUALIFIED_P (op)));
8863 qualified_p = false;
8865 function = tsubst_copy_and_build (function, args, complain,
8868 if (BASELINK_P (function))
8872 call_args = RECUR (TREE_OPERAND (t, 1));
8874 /* We do not perform argument-dependent lookup if normal
8875 lookup finds a non-function, in accordance with the
8876 expected resolution of DR 218. */
8878 && ((is_overloaded_fn (function)
8879 /* If lookup found a member function, the Koenig lookup is
8880 not appropriate, even if an unqualified-name was used
8881 to denote the function. */
8882 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8883 || TREE_CODE (function) == IDENTIFIER_NODE))
8884 function = perform_koenig_lookup (function, call_args);
8886 if (TREE_CODE (function) == IDENTIFIER_NODE)
8888 unqualified_name_lookup_error (function);
8889 return error_mark_node;
8892 /* Remember that there was a reference to this entity. */
8893 if (DECL_P (function))
8894 mark_used (function);
8896 if (TREE_CODE (function) == OFFSET_REF)
8897 return build_offset_ref_call_from_tree (function, call_args);
8898 if (TREE_CODE (function) == COMPONENT_REF)
8900 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8901 return finish_call_expr (function, call_args,
8902 /*disallow_virtual=*/false,
8903 /*koenig_p=*/false);
8905 return (build_new_method_call
8906 (TREE_OPERAND (function, 0),
8907 TREE_OPERAND (function, 1),
8908 call_args, NULL_TREE,
8909 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
8912 return finish_call_expr (function, call_args,
8913 /*disallow_virtual=*/qualified_p,
8918 return build_x_conditional_expr
8919 (RECUR (TREE_OPERAND (t, 0)),
8920 RECUR (TREE_OPERAND (t, 1)),
8921 RECUR (TREE_OPERAND (t, 2)));
8923 case PSEUDO_DTOR_EXPR:
8924 return finish_pseudo_destructor_expr
8925 (RECUR (TREE_OPERAND (t, 0)),
8926 RECUR (TREE_OPERAND (t, 1)),
8927 RECUR (TREE_OPERAND (t, 2)));
8931 tree purpose, value, chain;
8933 if (t == void_list_node)
8936 purpose = TREE_PURPOSE (t);
8938 purpose = RECUR (purpose);
8939 value = TREE_VALUE (t);
8941 value = RECUR (value);
8942 chain = TREE_CHAIN (t);
8943 if (chain && chain != void_type_node)
8944 chain = RECUR (chain);
8945 if (purpose == TREE_PURPOSE (t)
8946 && value == TREE_VALUE (t)
8947 && chain == TREE_CHAIN (t))
8949 return tree_cons (purpose, value, chain);
8958 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8959 args, complain, in_decl);
8960 /* Remember that there was a reference to this entity. */
8961 if (DECL_P (object))
8963 object_type = TREE_TYPE (object);
8965 member = TREE_OPERAND (t, 1);
8966 if (BASELINK_P (member))
8967 member = tsubst_baselink (member,
8968 non_reference (TREE_TYPE (object)),
8969 args, complain, in_decl);
8971 member = tsubst_copy (member, args, complain, in_decl);
8972 if (member == error_mark_node)
8973 return error_mark_node;
8975 if (object_type && !CLASS_TYPE_P (object_type))
8977 if (TREE_CODE (member) == BIT_NOT_EXPR)
8978 return finish_pseudo_destructor_expr (object,
8981 else if (TREE_CODE (member) == SCOPE_REF
8982 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8983 return finish_pseudo_destructor_expr (object,
8987 else if (TREE_CODE (member) == SCOPE_REF
8988 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8993 /* Lookup the template functions now that we know what the
8995 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8996 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8997 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8998 /*is_type_p=*/false,
8999 /*complain=*/false);
9000 if (BASELINK_P (member))
9002 BASELINK_FUNCTIONS (member)
9003 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
9005 member = (adjust_result_of_qualified_name_lookup
9006 (member, BINFO_TYPE (BASELINK_BINFO (member)),
9011 qualified_name_lookup_error (object_type, tmpl, member);
9012 return error_mark_node;
9015 else if (TREE_CODE (member) == SCOPE_REF
9016 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
9017 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
9019 if (complain & tf_error)
9021 if (TYPE_P (TREE_OPERAND (member, 0)))
9022 error ("%qT is not a class or namespace",
9023 TREE_OPERAND (member, 0));
9025 error ("%qD is not a class or namespace",
9026 TREE_OPERAND (member, 0));
9028 return error_mark_node;
9030 else if (TREE_CODE (member) == FIELD_DECL)
9031 return finish_non_static_data_member (member, object, NULL_TREE);
9033 return finish_class_member_access_expr (object, member,
9034 /*template_p=*/false);
9039 (RECUR (TREE_OPERAND (t, 0)));
9043 VEC(constructor_elt,gc) *n;
9044 constructor_elt *ce;
9045 unsigned HOST_WIDE_INT idx;
9047 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9048 bool process_index_p;
9050 /* digest_init will do the wrong thing if we let it. */
9051 if (type && TYPE_PTRMEMFUNC_P (type))
9054 /* We do not want to process the index of aggregate
9055 initializers as they are identifier nodes which will be
9056 looked up by digest_init. */
9057 process_index_p = !(type && IS_AGGR_TYPE (type));
9059 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
9060 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
9062 if (ce->index && process_index_p)
9063 ce->index = RECUR (ce->index);
9064 ce->value = RECUR (ce->value);
9067 r = build_constructor (NULL_TREE, n);
9068 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
9071 return digest_init (type, r);
9077 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
9078 if (TYPE_P (operand_0))
9079 return get_typeid (operand_0);
9080 return build_typeid (operand_0);
9090 tree r = tsubst_copy (t, args, complain, in_decl);
9092 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
9093 /* If the original type was a reference, we'll be wrapped in
9094 the appropriate INDIRECT_REF. */
9095 r = convert_from_reference (r);
9100 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
9101 tsubst_copy (TREE_TYPE (t), args, complain,
9105 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
9109 tree old_stmt_expr = cur_stmt_expr;
9110 tree stmt_expr = begin_stmt_expr ();
9112 cur_stmt_expr = stmt_expr;
9113 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
9114 stmt_expr = finish_stmt_expr (stmt_expr, false);
9115 cur_stmt_expr = old_stmt_expr;
9121 t = tsubst_copy (t, args, complain, in_decl);
9122 /* As in finish_id_expression, we resolve enumeration constants
9123 to their underlying values. */
9124 if (TREE_CODE (t) == CONST_DECL)
9125 return DECL_INITIAL (t);
9129 /* Handle Objective-C++ constructs, if appropriate. */
9132 = objcp_tsubst_copy_and_build (t, args, complain,
9133 in_decl, /*function_p=*/false);
9137 return tsubst_copy (t, args, complain, in_decl);
9143 /* Verify that the instantiated ARGS are valid. For type arguments,
9144 make sure that the type's linkage is ok. For non-type arguments,
9145 make sure they are constants if they are integral or enumerations.
9146 Emit an error under control of COMPLAIN, and return TRUE on error. */
9149 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
9151 int ix, len = DECL_NTPARMS (tmpl);
9152 bool result = false;
9154 for (ix = 0; ix != len; ix++)
9156 tree t = TREE_VEC_ELT (args, ix);
9160 /* [basic.link]: A name with no linkage (notably, the name
9161 of a class or enumeration declared in a local scope)
9162 shall not be used to declare an entity with linkage.
9163 This implies that names with no linkage cannot be used as
9164 template arguments. */
9165 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
9169 /* DR 488 makes use of a type with no linkage cause
9170 type deduction to fail. */
9171 if (complain & tf_error)
9173 if (TYPE_ANONYMOUS_P (nt))
9174 error ("%qT is/uses anonymous type", t);
9176 error ("template argument for %qD uses local type %qT",
9181 /* In order to avoid all sorts of complications, we do not
9182 allow variably-modified types as template arguments. */
9183 else if (variably_modified_type_p (t, NULL_TREE))
9185 if (complain & tf_error)
9186 error ("%qT is a variably modified type", t);
9190 /* A non-type argument of integral or enumerated type must be a
9192 else if (TREE_TYPE (t)
9193 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
9194 && !TREE_CONSTANT (t))
9196 if (complain & tf_error)
9197 error ("integral expression %qE is not constant", t);
9201 if (result && (complain & tf_error))
9202 error (" trying to instantiate %qD", tmpl);
9206 /* Instantiate the indicated variable or function template TMPL with
9207 the template arguments in TARG_PTR. */
9210 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
9216 if (tmpl == error_mark_node)
9217 return error_mark_node;
9219 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
9221 /* If this function is a clone, handle it specially. */
9222 if (DECL_CLONED_FUNCTION_P (tmpl))
9227 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
9229 if (spec == error_mark_node)
9230 return error_mark_node;
9232 /* Look for the clone. */
9233 FOR_EACH_CLONE (clone, spec)
9234 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9236 /* We should always have found the clone by now. */
9241 /* Check to see if we already have this specialization. */
9242 spec = retrieve_specialization (tmpl, targ_ptr,
9243 /*class_specializations_p=*/false);
9244 if (spec != NULL_TREE)
9247 gen_tmpl = most_general_template (tmpl);
9248 if (tmpl != gen_tmpl)
9250 /* The TMPL is a partial instantiation. To get a full set of
9251 arguments we must add the arguments used to perform the
9252 partial instantiation. */
9253 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9256 /* Check to see if we already have this specialization. */
9257 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9258 /*class_specializations_p=*/false);
9259 if (spec != NULL_TREE)
9263 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9265 return error_mark_node;
9267 /* We are building a FUNCTION_DECL, during which the access of its
9268 parameters and return types have to be checked. However this
9269 FUNCTION_DECL which is the desired context for access checking
9270 is not built yet. We solve this chicken-and-egg problem by
9271 deferring all checks until we have the FUNCTION_DECL. */
9272 push_deferring_access_checks (dk_deferred);
9274 /* Substitute template parameters. */
9275 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9276 targ_ptr, complain, gen_tmpl);
9277 if (fndecl == error_mark_node)
9278 return error_mark_node;
9280 /* Now we know the specialization, compute access previously
9282 push_access_scope (fndecl);
9283 perform_deferred_access_checks ();
9284 pop_access_scope (fndecl);
9285 pop_deferring_access_checks ();
9287 /* The DECL_TI_TEMPLATE should always be the immediate parent
9288 template, not the most general template. */
9289 DECL_TI_TEMPLATE (fndecl) = tmpl;
9291 /* If we've just instantiated the main entry point for a function,
9292 instantiate all the alternate entry points as well. We do this
9293 by cloning the instantiation of the main entry point, not by
9294 instantiating the template clones. */
9295 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9296 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9301 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9302 arguments that are being used when calling it. TARGS is a vector
9303 into which the deduced template arguments are placed.
9305 Return zero for success, 2 for an incomplete match that doesn't resolve
9306 all the types, and 1 for complete failure. An error message will be
9307 printed only for an incomplete match.
9309 If FN is a conversion operator, or we are trying to produce a specific
9310 specialization, RETURN_TYPE is the return type desired.
9312 The EXPLICIT_TARGS are explicit template arguments provided via a
9315 The parameter STRICT is one of:
9318 We are deducing arguments for a function call, as in
9322 We are deducing arguments for a conversion function, as in
9326 We are deducing arguments when doing an explicit instantiation
9327 as in [temp.explicit], when determining an explicit specialization
9328 as in [temp.expl.spec], or when taking the address of a function
9329 template, as in [temp.deduct.funcaddr]. */
9332 fn_type_unification (tree fn,
9333 tree explicit_targs,
9337 unification_kind_t strict,
9344 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9346 fntype = TREE_TYPE (fn);
9351 The specified template arguments must match the template
9352 parameters in kind (i.e., type, nontype, template), and there
9353 must not be more arguments than there are parameters;
9354 otherwise type deduction fails.
9356 Nontype arguments must match the types of the corresponding
9357 nontype template parameters, or must be convertible to the
9358 types of the corresponding nontype parameters as specified in
9359 _temp.arg.nontype_, otherwise type deduction fails.
9361 All references in the function type of the function template
9362 to the corresponding template parameters are replaced by the
9363 specified template argument values. If a substitution in a
9364 template parameter or in the function type of the function
9365 template results in an invalid type, type deduction fails. */
9367 tree converted_args;
9370 if (explicit_targs == error_mark_node)
9374 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9375 explicit_targs, NULL_TREE, tf_none,
9376 /*require_all_args=*/false,
9377 /*use_default_args=*/false));
9378 if (converted_args == error_mark_node)
9381 /* Substitute the explicit args into the function type. This is
9382 necessary so that, for instance, explicitly declared function
9383 arguments can match null pointed constants. If we were given
9384 an incomplete set of explicit args, we must not do semantic
9385 processing during substitution as we could create partial
9387 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9388 processing_template_decl += incomplete;
9389 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9390 processing_template_decl -= incomplete;
9392 if (fntype == error_mark_node)
9395 /* Place the explicitly specified arguments in TARGS. */
9396 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9397 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9400 parms = TYPE_ARG_TYPES (fntype);
9401 /* Never do unification on the 'this' parameter. */
9402 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9403 parms = TREE_CHAIN (parms);
9407 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9408 args = tree_cons (NULL_TREE, return_type, args);
9411 /* We allow incomplete unification without an error message here
9412 because the standard doesn't seem to explicitly prohibit it. Our
9413 callers must be ready to deal with unification failures in any
9415 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9416 targs, parms, args, /*subr=*/0,
9420 /* All is well so far. Now, check:
9424 When all template arguments have been deduced, all uses of
9425 template parameters in nondeduced contexts are replaced with
9426 the corresponding deduced argument values. If the
9427 substitution results in an invalid type, as described above,
9428 type deduction fails. */
9429 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9436 /* Adjust types before performing type deduction, as described in
9437 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9438 sections are symmetric. PARM is the type of a function parameter
9439 or the return type of the conversion function. ARG is the type of
9440 the argument passed to the call, or the type of the value
9441 initialized with the result of the conversion function. */
9444 maybe_adjust_types_for_deduction (unification_kind_t strict,
9457 /* Swap PARM and ARG throughout the remainder of this
9458 function; the handling is precisely symmetric since PARM
9459 will initialize ARG rather than vice versa. */
9467 /* There is nothing to do in this case. */
9474 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9476 /* [temp.deduct.call]
9478 If P is not a reference type:
9480 --If A is an array type, the pointer type produced by the
9481 array-to-pointer standard conversion (_conv.array_) is
9482 used in place of A for type deduction; otherwise,
9484 --If A is a function type, the pointer type produced by
9485 the function-to-pointer standard conversion
9486 (_conv.func_) is used in place of A for type deduction;
9489 --If A is a cv-qualified type, the top level
9490 cv-qualifiers of A's type are ignored for type
9492 if (TREE_CODE (*arg) == ARRAY_TYPE)
9493 *arg = build_pointer_type (TREE_TYPE (*arg));
9494 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9495 *arg = build_pointer_type (*arg);
9497 *arg = TYPE_MAIN_VARIANT (*arg);
9500 /* [temp.deduct.call]
9502 If P is a cv-qualified type, the top level cv-qualifiers
9503 of P's type are ignored for type deduction. If P is a
9504 reference type, the type referred to by P is used for
9506 *parm = TYPE_MAIN_VARIANT (*parm);
9507 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9509 *parm = TREE_TYPE (*parm);
9510 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9513 /* DR 322. For conversion deduction, remove a reference type on parm
9514 too (which has been swapped into ARG). */
9515 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9516 *arg = TREE_TYPE (*arg);
9521 /* Most parms like fn_type_unification.
9523 If SUBR is 1, we're being called recursively (to unify the
9524 arguments of a function or method parameter of a function
9528 type_unification_real (tree tparms,
9533 unification_kind_t strict,
9538 int ntparms = TREE_VEC_LENGTH (tparms);
9540 int saw_undeduced = 0;
9543 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9544 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9545 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9546 gcc_assert (ntparms > 0);
9551 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9552 | UNIFY_ALLOW_DERIVED);
9556 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9560 sub_strict = UNIFY_ALLOW_NONE;
9571 while (parms && parms != void_list_node
9572 && args && args != void_list_node)
9574 parm = TREE_VALUE (parms);
9575 parms = TREE_CHAIN (parms);
9576 arg = TREE_VALUE (args);
9577 args = TREE_CHAIN (args);
9579 if (arg == error_mark_node)
9581 if (arg == unknown_type_node)
9582 /* We can't deduce anything from this, but we might get all the
9583 template args from other function args. */
9586 /* Conversions will be performed on a function argument that
9587 corresponds with a function parameter that contains only
9588 non-deducible template parameters and explicitly specified
9589 template parameters. */
9590 if (!uses_template_parms (parm))
9595 type = TREE_TYPE (arg);
9599 if (same_type_p (parm, type))
9601 if (strict != DEDUCE_EXACT
9602 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
9611 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9612 if (type_unknown_p (arg))
9614 /* [temp.deduct.type] A template-argument can be deduced from
9615 a pointer to function or pointer to member function
9616 argument if the set of overloaded functions does not
9617 contain function templates and at most one of a set of
9618 overloaded functions provides a unique match. */
9620 if (resolve_overloaded_unification
9621 (tparms, targs, parm, arg, strict, sub_strict)
9626 arg = TREE_TYPE (arg);
9627 if (arg == error_mark_node)
9632 int arg_strict = sub_strict;
9635 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9637 if (unify (tparms, targs, parm, arg, arg_strict))
9642 /* Fail if we've reached the end of the parm list, and more args
9643 are present, and the parm list isn't variadic. */
9644 if (args && args != void_list_node && parms == void_list_node)
9646 /* Fail if parms are left and they don't have default values. */
9647 if (parms && parms != void_list_node
9648 && TREE_PURPOSE (parms) == NULL_TREE)
9652 for (i = 0; i < ntparms; i++)
9653 if (!TREE_VEC_ELT (targs, i))
9655 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9657 /* If this is an undeduced nontype parameter that depends on
9658 a type parameter, try another pass; its type may have been
9659 deduced from a later argument than the one from which
9660 this parameter can be deduced. */
9661 if (TREE_CODE (tparm) == PARM_DECL
9662 && uses_template_parms (TREE_TYPE (tparm))
9663 && !saw_undeduced++)
9672 /* Subroutine of type_unification_real. Args are like the variables at the
9673 call site. ARG is an overloaded function (or template-id); we try
9674 deducing template args from each of the overloads, and if only one
9675 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9678 resolve_overloaded_unification (tree tparms,
9682 unification_kind_t strict,
9685 tree tempargs = copy_node (targs);
9689 if (TREE_CODE (arg) == ADDR_EXPR)
9691 arg = TREE_OPERAND (arg, 0);
9697 if (TREE_CODE (arg) == COMPONENT_REF)
9698 /* Handle `&x' where `x' is some static or non-static member
9700 arg = TREE_OPERAND (arg, 1);
9702 if (TREE_CODE (arg) == OFFSET_REF)
9703 arg = TREE_OPERAND (arg, 1);
9705 /* Strip baselink information. */
9706 if (BASELINK_P (arg))
9707 arg = BASELINK_FUNCTIONS (arg);
9709 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9711 /* If we got some explicit template args, we need to plug them into
9712 the affected templates before we try to unify, in case the
9713 explicit args will completely resolve the templates in question. */
9715 tree expl_subargs = TREE_OPERAND (arg, 1);
9716 arg = TREE_OPERAND (arg, 0);
9718 for (; arg; arg = OVL_NEXT (arg))
9720 tree fn = OVL_CURRENT (arg);
9723 if (TREE_CODE (fn) != TEMPLATE_DECL)
9726 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9727 expl_subargs, /*check_ret=*/false);
9730 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9731 good += try_one_overload (tparms, targs, tempargs, parm,
9732 elem, strict, sub_strict, addr_p);
9738 gcc_assert (TREE_CODE (arg) == OVERLOAD
9739 || TREE_CODE (arg) == FUNCTION_DECL);
9741 for (; arg; arg = OVL_NEXT (arg))
9742 good += try_one_overload (tparms, targs, tempargs, parm,
9743 TREE_TYPE (OVL_CURRENT (arg)),
9744 strict, sub_strict, addr_p);
9747 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9748 to function or pointer to member function argument if the set of
9749 overloaded functions does not contain function templates and at most
9750 one of a set of overloaded functions provides a unique match.
9752 So if we found multiple possibilities, we return success but don't
9757 int i = TREE_VEC_LENGTH (targs);
9759 if (TREE_VEC_ELT (tempargs, i))
9760 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9768 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9769 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9770 different overloads deduce different arguments for a given parm.
9771 ADDR_P is true if the expression for which deduction is being
9772 performed was of the form "& fn" rather than simply "fn".
9774 Returns 1 on success. */
9777 try_one_overload (tree tparms,
9782 unification_kind_t strict,
9790 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9791 to function or pointer to member function argument if the set of
9792 overloaded functions does not contain function templates and at most
9793 one of a set of overloaded functions provides a unique match.
9795 So if this is a template, just return success. */
9797 if (uses_template_parms (arg))
9800 if (TREE_CODE (arg) == METHOD_TYPE)
9801 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9803 arg = build_pointer_type (arg);
9805 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9807 /* We don't copy orig_targs for this because if we have already deduced
9808 some template args from previous args, unify would complain when we
9809 try to deduce a template parameter for the same argument, even though
9810 there isn't really a conflict. */
9811 nargs = TREE_VEC_LENGTH (targs);
9812 tempargs = make_tree_vec (nargs);
9814 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9817 /* First make sure we didn't deduce anything that conflicts with
9818 explicitly specified args. */
9819 for (i = nargs; i--; )
9821 tree elt = TREE_VEC_ELT (tempargs, i);
9822 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9826 else if (uses_template_parms (elt))
9827 /* Since we're unifying against ourselves, we will fill in
9828 template args used in the function parm list with our own
9829 template parms. Discard them. */
9830 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9831 else if (oldelt && !template_args_equal (oldelt, elt))
9835 for (i = nargs; i--; )
9837 tree elt = TREE_VEC_ELT (tempargs, i);
9840 TREE_VEC_ELT (targs, i) = elt;
9846 /* PARM is a template class (perhaps with unbound template
9847 parameters). ARG is a fully instantiated type. If ARG can be
9848 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9849 TARGS are as for unify. */
9852 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9856 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9857 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9858 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9861 /* We need to make a new template argument vector for the call to
9862 unify. If we used TARGS, we'd clutter it up with the result of
9863 the attempted unification, even if this class didn't work out.
9864 We also don't want to commit ourselves to all the unifications
9865 we've already done, since unification is supposed to be done on
9866 an argument-by-argument basis. In other words, consider the
9867 following pathological case:
9869 template <int I, int J, int K>
9872 template <int I, int J>
9873 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9875 template <int I, int J, int K>
9876 void f(S<I, J, K>, S<I, I, I>);
9885 Now, by the time we consider the unification involving `s2', we
9886 already know that we must have `f<0, 0, 0>'. But, even though
9887 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9888 because there are two ways to unify base classes of S<0, 1, 2>
9889 with S<I, I, I>. If we kept the already deduced knowledge, we
9890 would reject the possibility I=1. */
9891 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9893 /* If unification failed, we're done. */
9894 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9895 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9901 /* Given a template type PARM and a class type ARG, find the unique
9902 base type in ARG that is an instance of PARM. We do not examine
9903 ARG itself; only its base-classes. If there is not exactly one
9904 appropriate base class, return NULL_TREE. PARM may be the type of
9905 a partial specialization, as well as a plain template type. Used
9909 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9911 tree rval = NULL_TREE;
9914 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9916 binfo = TYPE_BINFO (complete_type (arg));
9918 /* The type could not be completed. */
9921 /* Walk in inheritance graph order. The search order is not
9922 important, and this avoids multiple walks of virtual bases. */
9923 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9925 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9929 /* If there is more than one satisfactory baseclass, then:
9933 If they yield more than one possible deduced A, the type
9937 if (rval && !same_type_p (r, rval))
9947 /* Returns the level of DECL, which declares a template parameter. */
9950 template_decl_level (tree decl)
9952 switch (TREE_CODE (decl))
9956 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9959 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9967 /* Decide whether ARG can be unified with PARM, considering only the
9968 cv-qualifiers of each type, given STRICT as documented for unify.
9969 Returns nonzero iff the unification is OK on that basis. */
9972 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9974 int arg_quals = cp_type_quals (arg);
9975 int parm_quals = cp_type_quals (parm);
9977 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9978 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9980 /* Although a CVR qualifier is ignored when being applied to a
9981 substituted template parameter ([8.3.2]/1 for example), that
9982 does not apply during deduction [14.8.2.4]/1, (even though
9983 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9984 this). Except when we're allowing additional CV qualifiers
9985 at the outer level [14.8.2.1]/3,1st bullet. */
9986 if ((TREE_CODE (arg) == REFERENCE_TYPE
9987 || TREE_CODE (arg) == FUNCTION_TYPE
9988 || TREE_CODE (arg) == METHOD_TYPE)
9989 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9992 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9993 && (parm_quals & TYPE_QUAL_RESTRICT))
9997 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9998 && (arg_quals & parm_quals) != parm_quals)
10001 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
10002 && (parm_quals & arg_quals) != arg_quals)
10008 /* Deduce the value of template parameters. TPARMS is the (innermost)
10009 set of template parameters to a template. TARGS is the bindings
10010 for those template parameters, as determined thus far; TARGS may
10011 include template arguments for outer levels of template parameters
10012 as well. PARM is a parameter to a template function, or a
10013 subcomponent of that parameter; ARG is the corresponding argument.
10014 This function attempts to match PARM with ARG in a manner
10015 consistent with the existing assignments in TARGS. If more values
10016 are deduced, then TARGS is updated.
10018 Returns 0 if the type deduction succeeds, 1 otherwise. The
10019 parameter STRICT is a bitwise or of the following flags:
10022 Require an exact match between PARM and ARG.
10023 UNIFY_ALLOW_MORE_CV_QUAL:
10024 Allow the deduced ARG to be more cv-qualified (by qualification
10025 conversion) than ARG.
10026 UNIFY_ALLOW_LESS_CV_QUAL:
10027 Allow the deduced ARG to be less cv-qualified than ARG.
10028 UNIFY_ALLOW_DERIVED:
10029 Allow the deduced ARG to be a template base class of ARG,
10030 or a pointer to a template base class of the type pointed to by
10032 UNIFY_ALLOW_INTEGER:
10033 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
10034 case for more information.
10035 UNIFY_ALLOW_OUTER_LEVEL:
10036 This is the outermost level of a deduction. Used to determine validity
10037 of qualification conversions. A valid qualification conversion must
10038 have const qualified pointers leading up to the inner type which
10039 requires additional CV quals, except at the outer level, where const
10040 is not required [conv.qual]. It would be normal to set this flag in
10041 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
10042 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
10043 This is the outermost level of a deduction, and PARM can be more CV
10044 qualified at this point.
10045 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
10046 This is the outermost level of a deduction, and PARM can be less CV
10047 qualified at this point. */
10050 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
10055 int strict_in = strict;
10057 /* I don't think this will do the right thing with respect to types.
10058 But the only case I've seen it in so far has been array bounds, where
10059 signedness is the only information lost, and I think that will be
10061 while (TREE_CODE (parm) == NOP_EXPR)
10062 parm = TREE_OPERAND (parm, 0);
10064 if (arg == error_mark_node)
10066 if (arg == unknown_type_node)
10067 /* We can't deduce anything from this, but we might get all the
10068 template args from other function args. */
10071 /* If PARM uses template parameters, then we can't bail out here,
10072 even if ARG == PARM, since we won't record unifications for the
10073 template parameters. We might need them if we're trying to
10074 figure out which of two things is more specialized. */
10075 if (arg == parm && !uses_template_parms (parm))
10078 /* Immediately reject some pairs that won't unify because of
10079 cv-qualification mismatches. */
10080 if (TREE_CODE (arg) == TREE_CODE (parm)
10082 /* It is the elements of the array which hold the cv quals of an array
10083 type, and the elements might be template type parms. We'll check
10084 when we recurse. */
10085 && TREE_CODE (arg) != ARRAY_TYPE
10086 /* We check the cv-qualifiers when unifying with template type
10087 parameters below. We want to allow ARG `const T' to unify with
10088 PARM `T' for example, when computing which of two templates
10089 is more specialized, for example. */
10090 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
10091 && !check_cv_quals_for_unify (strict_in, arg, parm))
10094 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
10095 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
10096 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
10097 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
10098 strict &= ~UNIFY_ALLOW_DERIVED;
10099 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
10100 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
10102 switch (TREE_CODE (parm))
10104 case TYPENAME_TYPE:
10106 case UNBOUND_CLASS_TEMPLATE:
10107 /* In a type which contains a nested-name-specifier, template
10108 argument values cannot be deduced for template parameters used
10109 within the nested-name-specifier. */
10112 case TEMPLATE_TYPE_PARM:
10113 case TEMPLATE_TEMPLATE_PARM:
10114 case BOUND_TEMPLATE_TEMPLATE_PARM:
10115 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10117 if (TEMPLATE_TYPE_LEVEL (parm)
10118 != template_decl_level (tparm))
10119 /* The PARM is not one we're trying to unify. Just check
10120 to see if it matches ARG. */
10121 return (TREE_CODE (arg) == TREE_CODE (parm)
10122 && same_type_p (parm, arg)) ? 0 : 1;
10123 idx = TEMPLATE_TYPE_IDX (parm);
10124 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
10125 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
10127 /* Check for mixed types and values. */
10128 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
10129 && TREE_CODE (tparm) != TYPE_DECL)
10130 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10131 && TREE_CODE (tparm) != TEMPLATE_DECL))
10134 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10136 /* ARG must be constructed from a template class or a template
10137 template parameter. */
10138 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
10139 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
10143 tree parmvec = TYPE_TI_ARGS (parm);
10144 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
10146 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
10149 /* The resolution to DR150 makes clear that default
10150 arguments for an N-argument may not be used to bind T
10151 to a template template parameter with fewer than N
10152 parameters. It is not safe to permit the binding of
10153 default arguments as an extension, as that may change
10154 the meaning of a conforming program. Consider:
10156 struct Dense { static const unsigned int dim = 1; };
10158 template <template <typename> class View,
10160 void operator+(float, View<Block> const&);
10162 template <typename Block,
10163 unsigned int Dim = Block::dim>
10164 struct Lvalue_proxy { operator float() const; };
10168 Lvalue_proxy<Dense> p;
10173 Here, if Lvalue_proxy is permitted to bind to View, then
10174 the global operator+ will be used; if they are not, the
10175 Lvalue_proxy will be converted to float. */
10176 if (coerce_template_parms (argtmplvec, parmvec,
10177 TYPE_TI_TEMPLATE (parm),
10179 /*require_all_args=*/true,
10180 /*use_default_args=*/false)
10181 == error_mark_node)
10184 /* Deduce arguments T, i from TT<T> or TT<i>.
10185 We check each element of PARMVEC and ARGVEC individually
10186 rather than the whole TREE_VEC since they can have
10187 different number of elements. */
10189 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
10191 if (unify (tparms, targs,
10192 TREE_VEC_ELT (parmvec, i),
10193 TREE_VEC_ELT (argvec, i),
10198 arg = TYPE_TI_TEMPLATE (arg);
10200 /* Fall through to deduce template name. */
10203 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10204 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10206 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
10208 /* Simple cases: Value already set, does match or doesn't. */
10209 if (targ != NULL_TREE && template_args_equal (targ, arg))
10216 /* If PARM is `const T' and ARG is only `int', we don't have
10217 a match unless we are allowing additional qualification.
10218 If ARG is `const int' and PARM is just `T' that's OK;
10219 that binds `const int' to `T'. */
10220 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10224 /* Consider the case where ARG is `const volatile int' and
10225 PARM is `const T'. Then, T should be `volatile int'. */
10226 arg = cp_build_qualified_type_real
10227 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10228 if (arg == error_mark_node)
10231 /* Simple cases: Value already set, does match or doesn't. */
10232 if (targ != NULL_TREE && same_type_p (targ, arg))
10237 /* Make sure that ARG is not a variable-sized array. (Note
10238 that were talking about variable-sized arrays (like
10239 `int[n]'), rather than arrays of unknown size (like
10240 `int[]').) We'll get very confused by such a type since
10241 the bound of the array will not be computable in an
10242 instantiation. Besides, such types are not allowed in
10243 ISO C++, so we can do as we please here. */
10244 if (variably_modified_type_p (arg, NULL_TREE))
10248 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
10251 case TEMPLATE_PARM_INDEX:
10252 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10254 if (TEMPLATE_PARM_LEVEL (parm)
10255 != template_decl_level (tparm))
10256 /* The PARM is not one we're trying to unify. Just check
10257 to see if it matches ARG. */
10258 return !(TREE_CODE (arg) == TREE_CODE (parm)
10259 && cp_tree_equal (parm, arg));
10261 idx = TEMPLATE_PARM_IDX (parm);
10262 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
10265 return !cp_tree_equal (targ, arg);
10267 /* [temp.deduct.type] If, in the declaration of a function template
10268 with a non-type template-parameter, the non-type
10269 template-parameter is used in an expression in the function
10270 parameter-list and, if the corresponding template-argument is
10271 deduced, the template-argument type shall match the type of the
10272 template-parameter exactly, except that a template-argument
10273 deduced from an array bound may be of any integral type.
10274 The non-type parameter might use already deduced type parameters. */
10275 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10276 if (!TREE_TYPE (arg))
10277 /* Template-parameter dependent expression. Just accept it for now.
10278 It will later be processed in convert_template_argument. */
10280 else if (same_type_p (TREE_TYPE (arg), tparm))
10282 else if ((strict & UNIFY_ALLOW_INTEGER)
10283 && (TREE_CODE (tparm) == INTEGER_TYPE
10284 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10285 /* Convert the ARG to the type of PARM; the deduced non-type
10286 template argument must exactly match the types of the
10287 corresponding parameter. */
10288 arg = fold (build_nop (TREE_TYPE (parm), arg));
10289 else if (uses_template_parms (tparm))
10290 /* We haven't deduced the type of this parameter yet. Try again
10296 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
10301 /* A pointer-to-member constant can be unified only with
10302 another constant. */
10303 if (TREE_CODE (arg) != PTRMEM_CST)
10306 /* Just unify the class member. It would be useless (and possibly
10307 wrong, depending on the strict flags) to unify also
10308 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10309 arg refer to the same variable, even if through different
10310 classes. For instance:
10312 struct A { int x; };
10315 Unification of &A::x and &B::x must succeed. */
10316 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10317 PTRMEM_CST_MEMBER (arg), strict);
10322 if (TREE_CODE (arg) != POINTER_TYPE)
10325 /* [temp.deduct.call]
10327 A can be another pointer or pointer to member type that can
10328 be converted to the deduced A via a qualification
10329 conversion (_conv.qual_).
10331 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10332 This will allow for additional cv-qualification of the
10333 pointed-to types if appropriate. */
10335 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10336 /* The derived-to-base conversion only persists through one
10337 level of pointers. */
10338 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10340 return unify (tparms, targs, TREE_TYPE (parm),
10341 TREE_TYPE (arg), strict);
10344 case REFERENCE_TYPE:
10345 if (TREE_CODE (arg) != REFERENCE_TYPE)
10347 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10348 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10351 if (TREE_CODE (arg) != ARRAY_TYPE)
10353 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10354 != (TYPE_DOMAIN (arg) == NULL_TREE))
10356 if (TYPE_DOMAIN (parm) != NULL_TREE)
10361 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10362 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10364 /* Our representation of array types uses "N - 1" as the
10365 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10366 not an integer constant. */
10367 if (TREE_CODE (parm_max) == MINUS_EXPR)
10369 arg_max = fold_build2 (PLUS_EXPR,
10372 TREE_OPERAND (parm_max, 1));
10373 parm_max = TREE_OPERAND (parm_max, 0);
10376 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10379 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10380 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10387 case ENUMERAL_TYPE:
10389 if (TREE_CODE (arg) != TREE_CODE (parm))
10392 /* We have already checked cv-qualification at the top of the
10394 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10397 /* As far as unification is concerned, this wins. Later checks
10398 will invalidate it if necessary. */
10401 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10402 /* Type INTEGER_CST can come from ordinary constant template args. */
10404 while (TREE_CODE (arg) == NOP_EXPR)
10405 arg = TREE_OPERAND (arg, 0);
10407 if (TREE_CODE (arg) != INTEGER_CST)
10409 return !tree_int_cst_equal (parm, arg);
10414 if (TREE_CODE (arg) != TREE_VEC)
10416 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10418 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10419 if (unify (tparms, targs,
10420 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10428 if (TREE_CODE (arg) != TREE_CODE (parm))
10431 if (TYPE_PTRMEMFUNC_P (parm))
10433 if (!TYPE_PTRMEMFUNC_P (arg))
10436 return unify (tparms, targs,
10437 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10438 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10442 if (CLASSTYPE_TEMPLATE_INFO (parm))
10444 tree t = NULL_TREE;
10446 if (strict_in & UNIFY_ALLOW_DERIVED)
10448 /* First, we try to unify the PARM and ARG directly. */
10449 t = try_class_unification (tparms, targs,
10454 /* Fallback to the special case allowed in
10455 [temp.deduct.call]:
10457 If P is a class, and P has the form
10458 template-id, then A can be a derived class of
10459 the deduced A. Likewise, if P is a pointer to
10460 a class of the form template-id, A can be a
10461 pointer to a derived class pointed to by the
10463 t = get_template_base (tparms, targs, parm, arg);
10469 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10470 && (CLASSTYPE_TI_TEMPLATE (parm)
10471 == CLASSTYPE_TI_TEMPLATE (arg)))
10472 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10473 Then, we should unify `int' and `U'. */
10476 /* There's no chance of unification succeeding. */
10479 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10480 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10482 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10487 case FUNCTION_TYPE:
10488 if (TREE_CODE (arg) != TREE_CODE (parm))
10491 /* CV qualifications for methods can never be deduced, they must
10492 match exactly. We need to check them explicitly here,
10493 because type_unification_real treats them as any other
10494 cvqualified parameter. */
10495 if (TREE_CODE (parm) == METHOD_TYPE
10496 && (!check_cv_quals_for_unify
10498 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
10499 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
10502 if (unify (tparms, targs, TREE_TYPE (parm),
10503 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10505 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10506 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10510 /* Unify a pointer to member with a pointer to member function, which
10511 deduces the type of the member as a function type. */
10512 if (TYPE_PTRMEMFUNC_P (arg))
10516 cp_cv_quals cv_quals;
10518 /* Check top-level cv qualifiers */
10519 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10522 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10523 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10526 /* Determine the type of the function we are unifying against. */
10527 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10529 build_function_type (TREE_TYPE (method_type),
10530 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10532 /* Extract the cv-qualifiers of the member function from the
10533 implicit object parameter and place them on the function
10534 type to be restored later. */
10536 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10537 fntype = build_qualified_type (fntype, cv_quals);
10538 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10541 if (TREE_CODE (arg) != OFFSET_TYPE)
10543 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10544 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10546 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10550 if (DECL_TEMPLATE_PARM_P (parm))
10551 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10552 if (arg != integral_constant_value (parm))
10557 case TEMPLATE_DECL:
10558 /* Matched cases are handled by the ARG == PARM test above. */
10562 gcc_assert (EXPR_P (parm));
10564 /* We must be looking at an expression. This can happen with
10568 void foo(S<I>, S<I + 2>);
10570 This is a "nondeduced context":
10574 The nondeduced contexts are:
10576 --A type that is a template-id in which one or more of
10577 the template-arguments is an expression that references
10578 a template-parameter.
10580 In these cases, we assume deduction succeeded, but don't
10581 actually infer any unifications. */
10583 if (!uses_template_parms (parm)
10584 && !template_args_equal (parm, arg))
10591 /* Note that DECL can be defined in this translation unit, if
10595 mark_definable (tree decl)
10598 DECL_NOT_REALLY_EXTERN (decl) = 1;
10599 FOR_EACH_CLONE (clone, decl)
10600 DECL_NOT_REALLY_EXTERN (clone) = 1;
10603 /* Called if RESULT is explicitly instantiated, or is a member of an
10604 explicitly instantiated class. */
10607 mark_decl_instantiated (tree result, int extern_p)
10609 SET_DECL_EXPLICIT_INSTANTIATION (result);
10611 /* If this entity has already been written out, it's too late to
10612 make any modifications. */
10613 if (TREE_ASM_WRITTEN (result))
10616 if (TREE_CODE (result) != FUNCTION_DECL)
10617 /* The TREE_PUBLIC flag for function declarations will have been
10618 set correctly by tsubst. */
10619 TREE_PUBLIC (result) = 1;
10621 /* This might have been set by an earlier implicit instantiation. */
10622 DECL_COMDAT (result) = 0;
10625 DECL_NOT_REALLY_EXTERN (result) = 0;
10628 mark_definable (result);
10629 /* Always make artificials weak. */
10630 if (DECL_ARTIFICIAL (result) && flag_weak)
10631 comdat_linkage (result);
10632 /* For WIN32 we also want to put explicit instantiations in
10633 linkonce sections. */
10634 else if (TREE_PUBLIC (result))
10635 maybe_make_one_only (result);
10638 /* If EXTERN_P, then this function will not be emitted -- unless
10639 followed by an explicit instantiation, at which point its linkage
10640 will be adjusted. If !EXTERN_P, then this function will be
10641 emitted here. In neither circumstance do we want
10642 import_export_decl to adjust the linkage. */
10643 DECL_INTERFACE_KNOWN (result) = 1;
10646 /* Given two function templates PAT1 and PAT2, return:
10648 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10649 -1 if PAT2 is more specialized than PAT1.
10650 0 if neither is more specialized.
10652 LEN indicates the number of parameters we should consider
10653 (defaulted parameters should not be considered).
10655 The 1998 std underspecified function template partial ordering, and
10656 DR214 addresses the issue. We take pairs of arguments, one from
10657 each of the templates, and deduce them against each other. One of
10658 the templates will be more specialized if all the *other*
10659 template's arguments deduce against its arguments and at least one
10660 of its arguments *does* *not* deduce against the other template's
10661 corresponding argument. Deduction is done as for class templates.
10662 The arguments used in deduction have reference and top level cv
10663 qualifiers removed. Iff both arguments were originally reference
10664 types *and* deduction succeeds in both directions, the template
10665 with the more cv-qualified argument wins for that pairing (if
10666 neither is more cv-qualified, they both are equal). Unlike regular
10667 deduction, after all the arguments have been deduced in this way,
10668 we do *not* verify the deduced template argument values can be
10669 substituted into non-deduced contexts, nor do we have to verify
10670 that all template arguments have been deduced. */
10673 more_specialized_fn (tree pat1, tree pat2, int len)
10675 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10676 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10677 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10678 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10679 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10680 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10681 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10682 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10686 /* Remove the this parameter from non-static member functions. If
10687 one is a non-static member function and the other is not a static
10688 member function, remove the first parameter from that function
10689 also. This situation occurs for operator functions where we
10690 locate both a member function (with this pointer) and non-member
10691 operator (with explicit first operand). */
10692 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10694 len--; /* LEN is the number of significant arguments for DECL1 */
10695 args1 = TREE_CHAIN (args1);
10696 if (!DECL_STATIC_FUNCTION_P (decl2))
10697 args2 = TREE_CHAIN (args2);
10699 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10701 args2 = TREE_CHAIN (args2);
10702 if (!DECL_STATIC_FUNCTION_P (decl1))
10705 args1 = TREE_CHAIN (args1);
10709 /* If only one is a conversion operator, they are unordered. */
10710 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10713 /* Consider the return type for a conversion function */
10714 if (DECL_CONV_FN_P (decl1))
10716 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10717 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10721 processing_template_decl++;
10725 tree arg1 = TREE_VALUE (args1);
10726 tree arg2 = TREE_VALUE (args2);
10727 int deduce1, deduce2;
10731 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10733 arg1 = TREE_TYPE (arg1);
10734 quals1 = cp_type_quals (arg1);
10737 if (TREE_CODE (arg2) == REFERENCE_TYPE)
10739 arg2 = TREE_TYPE (arg2);
10740 quals2 = cp_type_quals (arg2);
10743 if ((quals1 < 0) != (quals2 < 0))
10745 /* Only of the args is a reference, see if we should apply
10746 array/function pointer decay to it. This is not part of
10747 DR214, but is, IMHO, consistent with the deduction rules
10748 for the function call itself, and with our earlier
10749 implementation of the underspecified partial ordering
10750 rules. (nathan). */
10753 switch (TREE_CODE (arg1))
10756 arg1 = TREE_TYPE (arg1);
10758 case FUNCTION_TYPE:
10759 arg1 = build_pointer_type (arg1);
10768 switch (TREE_CODE (arg2))
10771 arg2 = TREE_TYPE (arg2);
10773 case FUNCTION_TYPE:
10774 arg2 = build_pointer_type (arg2);
10783 arg1 = TYPE_MAIN_VARIANT (arg1);
10784 arg2 = TYPE_MAIN_VARIANT (arg2);
10786 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
10787 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
10793 if (better1 < 0 && better2 < 0)
10794 /* We've failed to deduce something in either direction.
10795 These must be unordered. */
10798 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
10800 /* Deduces in both directions, see if quals can
10801 disambiguate. Pretend the worse one failed to deduce. */
10802 if ((quals1 & quals2) == quals2)
10804 if ((quals1 & quals2) == quals1)
10807 if (deduce1 && !deduce2 && !better2)
10809 if (deduce2 && !deduce1 && !better1)
10812 args1 = TREE_CHAIN (args1);
10813 args2 = TREE_CHAIN (args2);
10816 processing_template_decl--;
10818 return (better1 > 0) - (better2 > 0);
10821 /* Determine which of two partial specializations is more specialized.
10823 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
10824 to the first partial specialization. The TREE_VALUE is the
10825 innermost set of template parameters for the partial
10826 specialization. PAT2 is similar, but for the second template.
10828 Return 1 if the first partial specialization is more specialized;
10829 -1 if the second is more specialized; 0 if neither is more
10832 See [temp.class.order] for information about determining which of
10833 two templates is more specialized. */
10836 more_specialized_class (tree pat1, tree pat2)
10842 tmpl1 = TREE_TYPE (pat1);
10843 tmpl2 = TREE_TYPE (pat2);
10845 /* Just like what happens for functions, if we are ordering between
10846 different class template specializations, we may encounter dependent
10847 types in the arguments, and we need our dependency check functions
10848 to behave correctly. */
10849 ++processing_template_decl;
10850 targs = get_class_bindings (TREE_VALUE (pat1),
10851 CLASSTYPE_TI_ARGS (tmpl1),
10852 CLASSTYPE_TI_ARGS (tmpl2));
10856 targs = get_class_bindings (TREE_VALUE (pat2),
10857 CLASSTYPE_TI_ARGS (tmpl2),
10858 CLASSTYPE_TI_ARGS (tmpl1));
10861 --processing_template_decl;
10866 /* Return the template arguments that will produce the function signature
10867 DECL from the function template FN, with the explicit template
10868 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
10869 also match. Return NULL_TREE if no satisfactory arguments could be
10873 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
10875 int ntparms = DECL_NTPARMS (fn);
10876 tree targs = make_tree_vec (ntparms);
10878 tree decl_arg_types;
10880 /* Substitute the explicit template arguments into the type of DECL.
10881 The call to fn_type_unification will handle substitution into the
10883 decl_type = TREE_TYPE (decl);
10884 if (explicit_args && uses_template_parms (decl_type))
10887 tree converted_args;
10889 if (DECL_TEMPLATE_INFO (decl))
10890 tmpl = DECL_TI_TEMPLATE (decl);
10892 /* We can get here for some invalid specializations. */
10896 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10897 explicit_args, NULL_TREE,
10899 /*require_all_args=*/false,
10900 /*use_default_args=*/false);
10901 if (converted_args == error_mark_node)
10904 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10905 if (decl_type == error_mark_node)
10909 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10910 /* Never do unification on the 'this' parameter. */
10911 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10912 decl_arg_types = TREE_CHAIN (decl_arg_types);
10914 if (fn_type_unification (fn, explicit_args, targs,
10916 (check_rettype || DECL_CONV_FN_P (fn)
10917 ? TREE_TYPE (decl_type) : NULL_TREE),
10918 DEDUCE_EXACT, LOOKUP_NORMAL))
10924 /* Return the innermost template arguments that, when applied to a
10925 template specialization whose innermost template parameters are
10926 TPARMS, and whose specialization arguments are PARMS, yield the
10929 For example, suppose we have:
10931 template <class T, class U> struct S {};
10932 template <class T> struct S<T*, int> {};
10934 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10935 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
10936 int}. The resulting vector will be {double}, indicating that `T'
10937 is bound to `double'. */
10940 get_class_bindings (tree tparms, tree spec_args, tree args)
10942 int i, ntparms = TREE_VEC_LENGTH (tparms);
10944 tree innermost_deduced_args;
10946 innermost_deduced_args = make_tree_vec (ntparms);
10947 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
10949 deduced_args = copy_node (args);
10950 SET_TMPL_ARGS_LEVEL (deduced_args,
10951 TMPL_ARGS_DEPTH (deduced_args),
10952 innermost_deduced_args);
10955 deduced_args = innermost_deduced_args;
10957 if (unify (tparms, deduced_args,
10958 INNERMOST_TEMPLATE_ARGS (spec_args),
10959 INNERMOST_TEMPLATE_ARGS (args),
10963 for (i = 0; i < ntparms; ++i)
10964 if (! TREE_VEC_ELT (innermost_deduced_args, i))
10967 /* Verify that nondeduced template arguments agree with the type
10968 obtained from argument deduction.
10972 struct A { typedef int X; };
10973 template <class T, class U> struct C {};
10974 template <class T> struct C<T, typename T::X> {};
10976 Then with the instantiation `C<A, int>', we can deduce that
10977 `T' is `A' but unify () does not check whether `typename T::X'
10979 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
10980 if (spec_args == error_mark_node
10981 /* We only need to check the innermost arguments; the other
10982 arguments will always agree. */
10983 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
10984 INNERMOST_TEMPLATE_ARGS (args)))
10987 return deduced_args;
10990 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
10991 Return the TREE_LIST node with the most specialized template, if
10992 any. If there is no most specialized template, the error_mark_node
10995 Note that this function does not look at, or modify, the
10996 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
10997 returned is one of the elements of INSTANTIATIONS, callers may
10998 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
10999 and retrieve it from the value returned. */
11002 most_specialized_instantiation (tree templates)
11006 ++processing_template_decl;
11009 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
11013 if (get_bindings (TREE_VALUE (champ),
11014 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
11015 NULL_TREE, /*check_ret=*/false))
11018 if (get_bindings (TREE_VALUE (fn),
11019 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
11020 NULL_TREE, /*check_ret=*/false))
11027 /* Equally specialized, move to next function. If there
11028 is no next function, nothing's most specialized. */
11029 fn = TREE_CHAIN (fn);
11037 /* Now verify that champ is better than everything earlier in the
11038 instantiation list. */
11039 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
11040 if (get_bindings (TREE_VALUE (champ),
11041 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
11042 NULL_TREE, /*check_ret=*/false)
11043 || !get_bindings (TREE_VALUE (fn),
11044 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
11045 NULL_TREE, /*check_ret=*/false))
11051 processing_template_decl--;
11054 return error_mark_node;
11059 /* If DECL is a specialization of some template, return the most
11060 general such template. Otherwise, returns NULL_TREE.
11062 For example, given:
11064 template <class T> struct S { template <class U> void f(U); };
11066 if TMPL is `template <class U> void S<int>::f(U)' this will return
11067 the full template. This function will not trace past partial
11068 specializations, however. For example, given in addition:
11070 template <class T> struct S<T*> { template <class U> void f(U); };
11072 if TMPL is `template <class U> void S<int*>::f(U)' this will return
11073 `template <class T> template <class U> S<T*>::f(U)'. */
11076 most_general_template (tree decl)
11078 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
11079 an immediate specialization. */
11080 if (TREE_CODE (decl) == FUNCTION_DECL)
11082 if (DECL_TEMPLATE_INFO (decl)) {
11083 decl = DECL_TI_TEMPLATE (decl);
11085 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
11086 template friend. */
11087 if (TREE_CODE (decl) != TEMPLATE_DECL)
11093 /* Look for more and more general templates. */
11094 while (DECL_TEMPLATE_INFO (decl))
11096 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
11097 (See cp-tree.h for details.) */
11098 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
11101 if (CLASS_TYPE_P (TREE_TYPE (decl))
11102 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
11105 /* Stop if we run into an explicitly specialized class template. */
11106 if (!DECL_NAMESPACE_SCOPE_P (decl)
11107 && DECL_CONTEXT (decl)
11108 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
11111 decl = DECL_TI_TEMPLATE (decl);
11117 /* Return the most specialized of the class template partial
11118 specializations of TMPL which can produce TYPE, a specialization of
11119 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
11120 a _TYPE node corresponding to the partial specialization, while the
11121 TREE_PURPOSE is the set of template arguments that must be
11122 substituted into the TREE_TYPE in order to generate TYPE.
11124 If the choice of partial specialization is ambiguous, a diagnostic
11125 is issued, and the error_mark_node is returned. If there are no
11126 partial specializations of TMPL matching TYPE, then NULL_TREE is
11130 most_specialized_class (tree type, tree tmpl)
11132 tree list = NULL_TREE;
11139 tmpl = most_general_template (tmpl);
11140 args = CLASSTYPE_TI_ARGS (type);
11141 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
11143 tree partial_spec_args;
11146 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
11147 spec_args = get_class_bindings (TREE_VALUE (t),
11152 list = tree_cons (spec_args, TREE_VALUE (t), list);
11153 TREE_TYPE (list) = TREE_TYPE (t);
11160 ambiguous_p = false;
11163 t = TREE_CHAIN (t);
11164 for (; t; t = TREE_CHAIN (t))
11166 fate = more_specialized_class (champ, t);
11173 t = TREE_CHAIN (t);
11176 ambiguous_p = true;
11185 for (t = list; t && t != champ; t = TREE_CHAIN (t))
11187 fate = more_specialized_class (champ, t);
11190 ambiguous_p = true;
11197 const char *str = "candidates are:";
11198 error ("ambiguous class template instantiation for %q#T", type);
11199 for (t = list; t; t = TREE_CHAIN (t))
11201 error ("%s %+#T", str, TREE_TYPE (t));
11204 return error_mark_node;
11210 /* Explicitly instantiate DECL. */
11213 do_decl_instantiation (tree decl, tree storage)
11215 tree result = NULL_TREE;
11218 if (!decl || decl == error_mark_node)
11219 /* An error occurred, for which grokdeclarator has already issued
11220 an appropriate message. */
11222 else if (! DECL_LANG_SPECIFIC (decl))
11224 error ("explicit instantiation of non-template %q#D", decl);
11227 else if (TREE_CODE (decl) == VAR_DECL)
11229 /* There is an asymmetry here in the way VAR_DECLs and
11230 FUNCTION_DECLs are handled by grokdeclarator. In the case of
11231 the latter, the DECL we get back will be marked as a
11232 template instantiation, and the appropriate
11233 DECL_TEMPLATE_INFO will be set up. This does not happen for
11234 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
11235 should handle VAR_DECLs as it currently handles
11237 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
11238 if (!result || TREE_CODE (result) != VAR_DECL)
11240 error ("no matching template for %qD found", decl);
11244 else if (TREE_CODE (decl) != FUNCTION_DECL)
11246 error ("explicit instantiation of %q#D", decl);
11252 /* Check for various error cases. Note that if the explicit
11253 instantiation is valid the RESULT will currently be marked as an
11254 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
11255 until we get here. */
11257 if (DECL_TEMPLATE_SPECIALIZATION (result))
11259 /* DR 259 [temp.spec].
11261 Both an explicit instantiation and a declaration of an explicit
11262 specialization shall not appear in a program unless the explicit
11263 instantiation follows a declaration of the explicit specialization.
11265 For a given set of template parameters, if an explicit
11266 instantiation of a template appears after a declaration of an
11267 explicit specialization for that template, the explicit
11268 instantiation has no effect. */
11271 else if (DECL_EXPLICIT_INSTANTIATION (result))
11275 No program shall explicitly instantiate any template more
11278 We check DECL_NOT_REALLY_EXTERN so as not to complain when
11279 the first instantiation was `extern' and the second is not,
11280 and EXTERN_P for the opposite case. */
11281 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
11282 pedwarn ("duplicate explicit instantiation of %q#D", result);
11283 /* If an "extern" explicit instantiation follows an ordinary
11284 explicit instantiation, the template is instantiated. */
11288 else if (!DECL_IMPLICIT_INSTANTIATION (result))
11290 error ("no matching template for %qD found", result);
11293 else if (!DECL_TEMPLATE_INFO (result))
11295 pedwarn ("explicit instantiation of non-template %q#D", result);
11299 if (storage == NULL_TREE)
11301 else if (storage == ridpointers[(int) RID_EXTERN])
11303 if (pedantic && !in_system_header)
11304 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11309 error ("storage class %qD applied to template instantiation", storage);
11311 check_explicit_instantiation_namespace (result);
11312 mark_decl_instantiated (result, extern_p);
11314 instantiate_decl (result, /*defer_ok=*/1,
11315 /*expl_inst_class_mem_p=*/false);
11319 mark_class_instantiated (tree t, int extern_p)
11321 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11322 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11323 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11324 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11327 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11328 rest_of_type_compilation (t, 1);
11332 /* Called from do_type_instantiation through binding_table_foreach to
11333 do recursive instantiation for the type bound in ENTRY. */
11335 bt_instantiate_type_proc (binding_entry entry, void *data)
11337 tree storage = *(tree *) data;
11339 if (IS_AGGR_TYPE (entry->type)
11340 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11341 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11344 /* Called from do_type_instantiation to instantiate a member
11345 (a member function or a static member variable) of an
11346 explicitly instantiated class template. */
11348 instantiate_class_member (tree decl, int extern_p)
11350 mark_decl_instantiated (decl, extern_p);
11352 instantiate_decl (decl, /*defer_ok=*/1,
11353 /*expl_inst_class_mem_p=*/true);
11356 /* Perform an explicit instantiation of template class T. STORAGE, if
11357 non-null, is the RID for extern, inline or static. COMPLAIN is
11358 nonzero if this is called from the parser, zero if called recursively,
11359 since the standard is unclear (as detailed below). */
11362 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11367 int previous_instantiation_extern_p = 0;
11369 if (TREE_CODE (t) == TYPE_DECL)
11372 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11374 error ("explicit instantiation of non-template type %qT", t);
11380 if (!COMPLETE_TYPE_P (t))
11382 if (complain & tf_error)
11383 error ("explicit instantiation of %q#T before definition of template",
11388 if (storage != NULL_TREE)
11390 if (pedantic && !in_system_header)
11391 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11394 if (storage == ridpointers[(int) RID_INLINE])
11396 else if (storage == ridpointers[(int) RID_EXTERN])
11398 else if (storage == ridpointers[(int) RID_STATIC])
11402 error ("storage class %qD applied to template instantiation",
11408 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11410 /* DR 259 [temp.spec].
11412 Both an explicit instantiation and a declaration of an explicit
11413 specialization shall not appear in a program unless the explicit
11414 instantiation follows a declaration of the explicit specialization.
11416 For a given set of template parameters, if an explicit
11417 instantiation of a template appears after a declaration of an
11418 explicit specialization for that template, the explicit
11419 instantiation has no effect. */
11422 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11426 No program shall explicitly instantiate any template more
11429 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11430 instantiation was `extern'. If EXTERN_P then the second is.
11431 These cases are OK. */
11432 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11434 if (!previous_instantiation_extern_p && !extern_p
11435 && (complain & tf_error))
11436 pedwarn ("duplicate explicit instantiation of %q#T", t);
11438 /* If we've already instantiated the template, just return now. */
11439 if (!CLASSTYPE_INTERFACE_ONLY (t))
11443 check_explicit_instantiation_namespace (TYPE_NAME (t));
11444 mark_class_instantiated (t, extern_p);
11452 /* In contrast to implicit instantiation, where only the
11453 declarations, and not the definitions, of members are
11454 instantiated, we have here:
11458 The explicit instantiation of a class template specialization
11459 implies the instantiation of all of its members not
11460 previously explicitly specialized in the translation unit
11461 containing the explicit instantiation.
11463 Of course, we can't instantiate member template classes, since
11464 we don't have any arguments for them. Note that the standard
11465 is unclear on whether the instantiation of the members are
11466 *explicit* instantiations or not. However, the most natural
11467 interpretation is that it should be an explicit instantiation. */
11470 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11471 if (TREE_CODE (tmp) == FUNCTION_DECL
11472 && DECL_TEMPLATE_INSTANTIATION (tmp))
11473 instantiate_class_member (tmp, extern_p);
11475 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11476 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11477 instantiate_class_member (tmp, extern_p);
11479 if (CLASSTYPE_NESTED_UTDS (t))
11480 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11481 bt_instantiate_type_proc, &storage);
11485 /* Given a function DECL, which is a specialization of TMPL, modify
11486 DECL to be a re-instantiation of TMPL with the same template
11487 arguments. TMPL should be the template into which tsubst'ing
11488 should occur for DECL, not the most general template.
11490 One reason for doing this is a scenario like this:
11493 void f(const T&, int i);
11495 void g() { f(3, 7); }
11498 void f(const T& t, const int i) { }
11500 Note that when the template is first instantiated, with
11501 instantiate_template, the resulting DECL will have no name for the
11502 first parameter, and the wrong type for the second. So, when we go
11503 to instantiate the DECL, we regenerate it. */
11506 regenerate_decl_from_template (tree decl, tree tmpl)
11508 /* The arguments used to instantiate DECL, from the most general
11513 args = DECL_TI_ARGS (decl);
11514 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11516 /* Make sure that we can see identifiers, and compute access
11518 push_access_scope (decl);
11520 if (TREE_CODE (decl) == FUNCTION_DECL)
11528 args_depth = TMPL_ARGS_DEPTH (args);
11529 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11530 if (args_depth > parms_depth)
11531 args = get_innermost_template_args (args, parms_depth);
11533 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11534 args, tf_error, NULL_TREE);
11536 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11539 /* Merge parameter declarations. */
11540 decl_parm = skip_artificial_parms_for (decl,
11541 DECL_ARGUMENTS (decl));
11543 = skip_artificial_parms_for (code_pattern,
11544 DECL_ARGUMENTS (code_pattern));
11550 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11551 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11552 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11554 parm_type = type_decays_to (parm_type);
11555 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11556 TREE_TYPE (decl_parm) = parm_type;
11557 attributes = DECL_ATTRIBUTES (pattern_parm);
11558 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11560 DECL_ATTRIBUTES (decl_parm) = attributes;
11561 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11563 decl_parm = TREE_CHAIN (decl_parm);
11564 pattern_parm = TREE_CHAIN (pattern_parm);
11567 /* Merge additional specifiers from the CODE_PATTERN. */
11568 if (DECL_DECLARED_INLINE_P (code_pattern)
11569 && !DECL_DECLARED_INLINE_P (decl))
11570 DECL_DECLARED_INLINE_P (decl) = 1;
11571 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11572 DECL_INLINE (decl) = 1;
11574 else if (TREE_CODE (decl) == VAR_DECL)
11575 DECL_INITIAL (decl) =
11576 tsubst_expr (DECL_INITIAL (code_pattern), args,
11577 tf_error, DECL_TI_TEMPLATE (decl));
11579 gcc_unreachable ();
11581 pop_access_scope (decl);
11584 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11585 substituted to get DECL. */
11588 template_for_substitution (tree decl)
11590 tree tmpl = DECL_TI_TEMPLATE (decl);
11592 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11593 for the instantiation. This is not always the most general
11594 template. Consider, for example:
11597 struct S { template <class U> void f();
11598 template <> void f<int>(); };
11600 and an instantiation of S<double>::f<int>. We want TD to be the
11601 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11602 while (/* An instantiation cannot have a definition, so we need a
11603 more general template. */
11604 DECL_TEMPLATE_INSTANTIATION (tmpl)
11605 /* We must also deal with friend templates. Given:
11607 template <class T> struct S {
11608 template <class U> friend void f() {};
11611 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11612 so far as the language is concerned, but that's still
11613 where we get the pattern for the instantiation from. On
11614 other hand, if the definition comes outside the class, say:
11616 template <class T> struct S {
11617 template <class U> friend void f();
11619 template <class U> friend void f() {}
11621 we don't need to look any further. That's what the check for
11622 DECL_INITIAL is for. */
11623 || (TREE_CODE (decl) == FUNCTION_DECL
11624 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11625 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11627 /* The present template, TD, should not be a definition. If it
11628 were a definition, we should be using it! Note that we
11629 cannot restructure the loop to just keep going until we find
11630 a template with a definition, since that might go too far if
11631 a specialization was declared, but not defined. */
11632 gcc_assert (TREE_CODE (decl) != VAR_DECL
11633 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11635 /* Fetch the more general template. */
11636 tmpl = DECL_TI_TEMPLATE (tmpl);
11642 /* Produce the definition of D, a _DECL generated from a template. If
11643 DEFER_OK is nonzero, then we don't have to actually do the
11644 instantiation now; we just have to do it sometime. Normally it is
11645 an error if this is an explicit instantiation but D is undefined.
11646 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
11647 explicitly instantiated class template. */
11650 instantiate_decl (tree d, int defer_ok,
11651 bool expl_inst_class_mem_p)
11653 tree tmpl = DECL_TI_TEMPLATE (d);
11660 bool pattern_defined;
11662 location_t saved_loc = input_location;
11665 /* This function should only be used to instantiate templates for
11666 functions and static member variables. */
11667 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11668 || TREE_CODE (d) == VAR_DECL);
11670 /* Variables are never deferred; if instantiation is required, they
11671 are instantiated right away. That allows for better code in the
11672 case that an expression refers to the value of the variable --
11673 if the variable has a constant value the referring expression can
11674 take advantage of that fact. */
11675 if (TREE_CODE (d) == VAR_DECL)
11678 /* Don't instantiate cloned functions. Instead, instantiate the
11679 functions they cloned. */
11680 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11681 d = DECL_CLONED_FUNCTION (d);
11683 if (DECL_TEMPLATE_INSTANTIATED (d))
11684 /* D has already been instantiated. It might seem reasonable to
11685 check whether or not D is an explicit instantiation, and, if so,
11686 stop here. But when an explicit instantiation is deferred
11687 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11688 is set, even though we still need to do the instantiation. */
11691 /* If we already have a specialization of this declaration, then
11692 there's no reason to instantiate it. Note that
11693 retrieve_specialization gives us both instantiations and
11694 specializations, so we must explicitly check
11695 DECL_TEMPLATE_SPECIALIZATION. */
11696 gen_tmpl = most_general_template (tmpl);
11697 gen_args = DECL_TI_ARGS (d);
11698 spec = retrieve_specialization (gen_tmpl, gen_args,
11699 /*class_specializations_p=*/false);
11700 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11703 /* This needs to happen before any tsubsting. */
11704 if (! push_tinst_level (d))
11707 timevar_push (TV_PARSE);
11709 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11710 for the instantiation. */
11711 td = template_for_substitution (d);
11712 code_pattern = DECL_TEMPLATE_RESULT (td);
11714 /* We should never be trying to instantiate a member of a class
11715 template or partial specialization. */
11716 gcc_assert (d != code_pattern);
11718 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11719 || DECL_TEMPLATE_SPECIALIZATION (td))
11720 /* In the case of a friend template whose definition is provided
11721 outside the class, we may have too many arguments. Drop the
11722 ones we don't need. The same is true for specializations. */
11723 args = get_innermost_template_args
11724 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11728 if (TREE_CODE (d) == FUNCTION_DECL)
11729 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11731 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11733 /* We may be in the middle of deferred access check. Disable it now. */
11734 push_deferring_access_checks (dk_no_deferred);
11736 /* Unless an explicit instantiation directive has already determined
11737 the linkage of D, remember that a definition is available for
11739 if (pattern_defined
11740 && !DECL_INTERFACE_KNOWN (d)
11741 && !DECL_NOT_REALLY_EXTERN (d))
11742 mark_definable (d);
11744 input_location = DECL_SOURCE_LOCATION (d);
11746 /* If D is a member of an explicitly instantiated class template,
11747 and no definition is available, treat it like an implicit
11749 if (!pattern_defined && expl_inst_class_mem_p
11750 && DECL_EXPLICIT_INSTANTIATION (d))
11752 DECL_NOT_REALLY_EXTERN (d) = 0;
11753 DECL_INTERFACE_KNOWN (d) = 0;
11754 SET_DECL_IMPLICIT_INSTANTIATION (d);
11759 /* Recheck the substitutions to obtain any warning messages
11760 about ignoring cv qualifiers. */
11761 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11762 tree type = TREE_TYPE (gen);
11764 /* Make sure that we can see identifiers, and compute access
11765 correctly. D is already the target FUNCTION_DECL with the
11767 push_access_scope (d);
11769 if (TREE_CODE (gen) == FUNCTION_DECL)
11771 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
11772 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11773 tf_warning_or_error, d);
11774 /* Don't simply tsubst the function type, as that will give
11775 duplicate warnings about poor parameter qualifications.
11776 The function arguments are the same as the decl_arguments
11777 without the top level cv qualifiers. */
11778 type = TREE_TYPE (type);
11780 tsubst (type, gen_args, tf_warning_or_error, d);
11782 pop_access_scope (d);
11785 /* Check to see whether we know that this template will be
11786 instantiated in some other file, as with "extern template"
11788 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
11789 /* In general, we do not instantiate such templates... */
11791 /* ... but we instantiate inline functions so that we can inline
11793 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
11794 /* ... we instantiate static data members whose values are
11795 needed in integral constant expressions. */
11796 && ! (TREE_CODE (d) == VAR_DECL
11797 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
11799 /* Defer all other templates, unless we have been explicitly
11800 forbidden from doing so. */
11801 if (/* If there is no definition, we cannot instantiate the
11804 /* If it's OK to postpone instantiation, do so. */
11806 /* If this is a static data member that will be defined
11807 elsewhere, we don't want to instantiate the entire data
11808 member, but we do want to instantiate the initializer so that
11809 we can substitute that elsewhere. */
11810 || (external_p && TREE_CODE (d) == VAR_DECL))
11812 /* The definition of the static data member is now required so
11813 we must substitute the initializer. */
11814 if (TREE_CODE (d) == VAR_DECL
11815 && !DECL_INITIAL (d)
11816 && DECL_INITIAL (code_pattern))
11821 ns = decl_namespace_context (d);
11822 push_nested_namespace (ns);
11823 push_nested_class (DECL_CONTEXT (d));
11824 init = tsubst_expr (DECL_INITIAL (code_pattern),
11826 tf_warning_or_error, NULL_TREE);
11827 DECL_INITIAL (d) = init;
11828 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
11829 /*asmspec_tree=*/NULL_TREE,
11830 LOOKUP_ONLYCONVERTING);
11831 pop_nested_class ();
11832 pop_nested_namespace (ns);
11835 /* We restore the source position here because it's used by
11836 add_pending_template. */
11837 input_location = saved_loc;
11839 if (at_eof && !pattern_defined
11840 && DECL_EXPLICIT_INSTANTIATION (d))
11843 The definition of a non-exported function template, a
11844 non-exported member function template, or a non-exported
11845 member function or static data member of a class template
11846 shall be present in every translation unit in which it is
11847 explicitly instantiated. */
11849 ("explicit instantiation of %qD but no definition available", d);
11851 /* ??? Historically, we have instantiated inline functions, even
11852 when marked as "extern template". */
11853 if (!(external_p && TREE_CODE (d) == VAR_DECL))
11854 add_pending_template (d);
11857 /* Tell the repository that D is available in this translation unit
11858 -- and see if it is supposed to be instantiated here. */
11859 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11861 /* In a PCH file, despite the fact that the repository hasn't
11862 requested instantiation in the PCH it is still possible that
11863 an instantiation will be required in a file that includes the
11866 add_pending_template (d);
11867 /* Instantiate inline functions so that the inliner can do its
11868 job, even though we'll not be emitting a copy of this
11870 if (!(TREE_CODE (d) == FUNCTION_DECL
11871 && flag_inline_trees
11872 && DECL_DECLARED_INLINE_P (d)))
11876 need_push = !cfun || !global_bindings_p ();
11878 push_to_top_level ();
11880 /* Mark D as instantiated so that recursive calls to
11881 instantiate_decl do not try to instantiate it again. */
11882 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11884 /* Regenerate the declaration in case the template has been modified
11885 by a subsequent redeclaration. */
11886 regenerate_decl_from_template (d, td);
11888 /* We already set the file and line above. Reset them now in case
11889 they changed as a result of calling regenerate_decl_from_template. */
11890 input_location = DECL_SOURCE_LOCATION (d);
11892 if (TREE_CODE (d) == VAR_DECL)
11894 /* Clear out DECL_RTL; whatever was there before may not be right
11895 since we've reset the type of the declaration. */
11896 SET_DECL_RTL (d, NULL_RTX);
11897 DECL_IN_AGGR_P (d) = 0;
11899 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11900 initializer. That function will defer actual emission until
11901 we have a chance to determine linkage. */
11902 DECL_EXTERNAL (d) = 0;
11904 /* Enter the scope of D so that access-checking works correctly. */
11905 push_nested_class (DECL_CONTEXT (d));
11906 finish_decl (d, DECL_INITIAL (d), NULL_TREE);
11907 pop_nested_class ();
11909 else if (TREE_CODE (d) == FUNCTION_DECL)
11911 htab_t saved_local_specializations;
11916 /* Save away the current list, in case we are instantiating one
11917 template from within the body of another. */
11918 saved_local_specializations = local_specializations;
11920 /* Set up the list of local specializations. */
11921 local_specializations = htab_create (37,
11922 hash_local_specialization,
11923 eq_local_specializations,
11926 /* Set up context. */
11927 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11929 /* Create substitution entries for the parameters. */
11930 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11931 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11932 spec_parm = DECL_ARGUMENTS (d);
11933 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11935 register_local_specialization (spec_parm, tmpl_parm);
11936 spec_parm = skip_artificial_parms_for (d, spec_parm);
11937 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11941 register_local_specialization (spec_parm, tmpl_parm);
11942 tmpl_parm = TREE_CHAIN (tmpl_parm);
11943 spec_parm = TREE_CHAIN (spec_parm);
11945 gcc_assert (!spec_parm);
11947 /* Substitute into the body of the function. */
11948 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11949 tf_warning_or_error, tmpl);
11951 /* We don't need the local specializations any more. */
11952 htab_delete (local_specializations);
11953 local_specializations = saved_local_specializations;
11955 /* Finish the function. */
11956 d = finish_function (0);
11957 expand_or_defer_fn (d);
11960 /* We're not deferring instantiation any more. */
11961 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11964 pop_from_top_level ();
11967 input_location = saved_loc;
11968 pop_deferring_access_checks ();
11969 pop_tinst_level ();
11971 timevar_pop (TV_PARSE);
11976 /* Run through the list of templates that we wish we could
11977 instantiate, and instantiate any we can. RETRIES is the
11978 number of times we retry pending template instantiation. */
11981 instantiate_pending_templates (int retries)
11984 tree last = NULL_TREE;
11986 location_t saved_loc = input_location;
11987 int saved_in_system_header = in_system_header;
11989 /* Instantiating templates may trigger vtable generation. This in turn
11990 may require further template instantiations. We place a limit here
11991 to avoid infinite loop. */
11992 if (pending_templates && retries >= max_tinst_depth)
11994 tree decl = TREE_VALUE (pending_templates);
11996 error ("template instantiation depth exceeds maximum of %d"
11997 " instantiating %q+D, possibly from virtual table generation"
11998 " (use -ftemplate-depth-NN to increase the maximum)",
11999 max_tinst_depth, decl);
12000 if (TREE_CODE (decl) == FUNCTION_DECL)
12001 /* Pretend that we defined it. */
12002 DECL_INITIAL (decl) = error_mark_node;
12010 t = &pending_templates;
12013 tree instantiation = TREE_VALUE (*t);
12015 reopen_tinst_level (TREE_PURPOSE (*t));
12017 if (TYPE_P (instantiation))
12021 if (!COMPLETE_TYPE_P (instantiation))
12023 instantiate_class_template (instantiation);
12024 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
12025 for (fn = TYPE_METHODS (instantiation);
12027 fn = TREE_CHAIN (fn))
12028 if (! DECL_ARTIFICIAL (fn))
12029 instantiate_decl (fn,
12031 /*expl_inst_class_mem_p=*/false);
12032 if (COMPLETE_TYPE_P (instantiation))
12036 if (COMPLETE_TYPE_P (instantiation))
12037 /* If INSTANTIATION has been instantiated, then we don't
12038 need to consider it again in the future. */
12039 *t = TREE_CHAIN (*t);
12043 t = &TREE_CHAIN (*t);
12048 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
12049 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
12052 = instantiate_decl (instantiation,
12054 /*expl_inst_class_mem_p=*/false);
12055 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
12059 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
12060 || DECL_TEMPLATE_INSTANTIATED (instantiation))
12061 /* If INSTANTIATION has been instantiated, then we don't
12062 need to consider it again in the future. */
12063 *t = TREE_CHAIN (*t);
12067 t = &TREE_CHAIN (*t);
12071 current_tinst_level = NULL_TREE;
12073 last_pending_template = last;
12075 while (reconsider);
12077 input_location = saved_loc;
12078 in_system_header = saved_in_system_header;
12081 /* Substitute ARGVEC into T, which is a list of initializers for
12082 either base class or a non-static data member. The TREE_PURPOSEs
12083 are DECLs, and the TREE_VALUEs are the initializer values. Used by
12084 instantiate_decl. */
12087 tsubst_initializer_list (tree t, tree argvec)
12089 tree inits = NULL_TREE;
12091 for (; t; t = TREE_CHAIN (t))
12096 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_warning_or_error,
12098 decl = expand_member_init (decl);
12099 if (decl && !DECL_P (decl))
12100 in_base_initializer = 1;
12102 init = tsubst_expr (TREE_VALUE (t), argvec, tf_warning_or_error,
12104 in_base_initializer = 0;
12108 init = build_tree_list (decl, init);
12109 TREE_CHAIN (init) = inits;
12116 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
12119 set_current_access_from_decl (tree decl)
12121 if (TREE_PRIVATE (decl))
12122 current_access_specifier = access_private_node;
12123 else if (TREE_PROTECTED (decl))
12124 current_access_specifier = access_protected_node;
12126 current_access_specifier = access_public_node;
12129 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
12130 is the instantiation (which should have been created with
12131 start_enum) and ARGS are the template arguments to use. */
12134 tsubst_enum (tree tag, tree newtag, tree args)
12138 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
12143 decl = TREE_VALUE (e);
12144 /* Note that in a template enum, the TREE_VALUE is the
12145 CONST_DECL, not the corresponding INTEGER_CST. */
12146 value = tsubst_expr (DECL_INITIAL (decl),
12147 args, tf_warning_or_error, NULL_TREE);
12149 /* Give this enumeration constant the correct access. */
12150 set_current_access_from_decl (decl);
12152 /* Actually build the enumerator itself. */
12153 build_enumerator (DECL_NAME (decl), value, newtag);
12156 finish_enum (newtag);
12157 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
12158 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
12161 /* DECL is a FUNCTION_DECL that is a template specialization. Return
12162 its type -- but without substituting the innermost set of template
12163 arguments. So, innermost set of template parameters will appear in
12167 get_mostly_instantiated_function_type (tree decl)
12175 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
12176 targs = DECL_TI_ARGS (decl);
12177 tparms = DECL_TEMPLATE_PARMS (tmpl);
12178 parm_depth = TMPL_PARMS_DEPTH (tparms);
12180 /* There should be as many levels of arguments as there are levels
12182 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
12184 fn_type = TREE_TYPE (tmpl);
12186 if (parm_depth == 1)
12187 /* No substitution is necessary. */
12191 int i, save_access_control;
12194 /* Replace the innermost level of the TARGS with NULL_TREEs to
12195 let tsubst know not to substitute for those parameters. */
12196 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
12197 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
12198 SET_TMPL_ARGS_LEVEL (partial_args, i,
12199 TMPL_ARGS_LEVEL (targs, i));
12200 SET_TMPL_ARGS_LEVEL (partial_args,
12201 TMPL_ARGS_DEPTH (targs),
12202 make_tree_vec (DECL_NTPARMS (tmpl)));
12204 /* Disable access control as this function is used only during
12206 save_access_control = flag_access_control;
12207 flag_access_control = 0;
12209 ++processing_template_decl;
12210 /* Now, do the (partial) substitution to figure out the
12211 appropriate function type. */
12212 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
12213 --processing_template_decl;
12215 /* Substitute into the template parameters to obtain the real
12216 innermost set of parameters. This step is important if the
12217 innermost set of template parameters contains value
12218 parameters whose types depend on outer template parameters. */
12219 TREE_VEC_LENGTH (partial_args)--;
12220 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
12222 flag_access_control = save_access_control;
12228 /* Return truthvalue if we're processing a template different from
12229 the last one involved in diagnostics. */
12231 problematic_instantiation_changed (void)
12233 return last_template_error_tick != tinst_level_tick;
12236 /* Remember current template involved in diagnostics. */
12238 record_last_problematic_instantiation (void)
12240 last_template_error_tick = tinst_level_tick;
12244 current_instantiation (void)
12246 return current_tinst_level;
12249 /* [temp.param] Check that template non-type parm TYPE is of an allowable
12250 type. Return zero for ok, nonzero for disallowed. Issue error and
12251 warning messages under control of COMPLAIN. */
12254 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
12256 if (INTEGRAL_TYPE_P (type))
12258 else if (POINTER_TYPE_P (type))
12260 else if (TYPE_PTR_TO_MEMBER_P (type))
12262 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
12264 else if (TREE_CODE (type) == TYPENAME_TYPE)
12267 if (complain & tf_error)
12268 error ("%q#T is not a valid type for a template constant parameter", type);
12272 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
12273 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
12276 dependent_type_p_r (tree type)
12282 A type is dependent if it is:
12284 -- a template parameter. Template template parameters are types
12285 for us (since TYPE_P holds true for them) so we handle
12287 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
12288 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
12290 /* -- a qualified-id with a nested-name-specifier which contains a
12291 class-name that names a dependent type or whose unqualified-id
12292 names a dependent type. */
12293 if (TREE_CODE (type) == TYPENAME_TYPE)
12295 /* -- a cv-qualified type where the cv-unqualified type is
12297 type = TYPE_MAIN_VARIANT (type);
12298 /* -- a compound type constructed from any dependent type. */
12299 if (TYPE_PTR_TO_MEMBER_P (type))
12300 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
12301 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
12303 else if (TREE_CODE (type) == POINTER_TYPE
12304 || TREE_CODE (type) == REFERENCE_TYPE)
12305 return dependent_type_p (TREE_TYPE (type));
12306 else if (TREE_CODE (type) == FUNCTION_TYPE
12307 || TREE_CODE (type) == METHOD_TYPE)
12311 if (dependent_type_p (TREE_TYPE (type)))
12313 for (arg_type = TYPE_ARG_TYPES (type);
12315 arg_type = TREE_CHAIN (arg_type))
12316 if (dependent_type_p (TREE_VALUE (arg_type)))
12320 /* -- an array type constructed from any dependent type or whose
12321 size is specified by a constant expression that is
12322 value-dependent. */
12323 if (TREE_CODE (type) == ARRAY_TYPE)
12325 if (TYPE_DOMAIN (type)
12326 && ((value_dependent_expression_p
12327 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
12328 || (type_dependent_expression_p
12329 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
12331 return dependent_type_p (TREE_TYPE (type));
12334 /* -- a template-id in which either the template name is a template
12336 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
12338 /* ... or any of the template arguments is a dependent type or
12339 an expression that is type-dependent or value-dependent. */
12340 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
12341 && (any_dependent_template_arguments_p
12342 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
12345 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
12346 expression is not type-dependent, then it should already been
12348 if (TREE_CODE (type) == TYPEOF_TYPE)
12351 /* The standard does not specifically mention types that are local
12352 to template functions or local classes, but they should be
12353 considered dependent too. For example:
12355 template <int I> void f() {
12360 The size of `E' cannot be known until the value of `I' has been
12361 determined. Therefore, `E' must be considered dependent. */
12362 scope = TYPE_CONTEXT (type);
12363 if (scope && TYPE_P (scope))
12364 return dependent_type_p (scope);
12365 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12366 return type_dependent_expression_p (scope);
12368 /* Other types are non-dependent. */
12372 /* Returns TRUE if TYPE is dependent, in the sense of
12373 [temp.dep.type]. */
12376 dependent_type_p (tree type)
12378 /* If there are no template parameters in scope, then there can't be
12379 any dependent types. */
12380 if (!processing_template_decl)
12382 /* If we are not processing a template, then nobody should be
12383 providing us with a dependent type. */
12385 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM);
12389 /* If the type is NULL, we have not computed a type for the entity
12390 in question; in that case, the type is dependent. */
12394 /* Erroneous types can be considered non-dependent. */
12395 if (type == error_mark_node)
12398 /* If we have not already computed the appropriate value for TYPE,
12400 if (!TYPE_DEPENDENT_P_VALID (type))
12402 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12403 TYPE_DEPENDENT_P_VALID (type) = 1;
12406 return TYPE_DEPENDENT_P (type);
12409 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12412 dependent_scope_ref_p (tree expression, bool criterion (tree))
12417 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12419 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12422 scope = TREE_OPERAND (expression, 0);
12423 name = TREE_OPERAND (expression, 1);
12427 An id-expression is type-dependent if it contains a
12428 nested-name-specifier that contains a class-name that names a
12430 /* The suggested resolution to Core Issue 2 implies that if the
12431 qualifying type is the current class, then we must peek
12434 && currently_open_class (scope)
12435 && !criterion (name))
12437 if (dependent_type_p (scope))
12443 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12444 [temp.dep.constexpr] */
12447 value_dependent_expression_p (tree expression)
12449 if (!processing_template_decl)
12452 /* A name declared with a dependent type. */
12453 if (DECL_P (expression) && type_dependent_expression_p (expression))
12456 switch (TREE_CODE (expression))
12458 case IDENTIFIER_NODE:
12459 /* A name that has not been looked up -- must be dependent. */
12462 case TEMPLATE_PARM_INDEX:
12463 /* A non-type template parm. */
12467 /* A non-type template parm. */
12468 if (DECL_TEMPLATE_PARM_P (expression))
12473 /* A constant with integral or enumeration type and is initialized
12474 with an expression that is value-dependent. */
12475 if (DECL_INITIAL (expression)
12476 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12477 && value_dependent_expression_p (DECL_INITIAL (expression)))
12481 case DYNAMIC_CAST_EXPR:
12482 case STATIC_CAST_EXPR:
12483 case CONST_CAST_EXPR:
12484 case REINTERPRET_CAST_EXPR:
12486 /* These expressions are value-dependent if the type to which
12487 the cast occurs is dependent or the expression being casted
12488 is value-dependent. */
12490 tree type = TREE_TYPE (expression);
12492 if (dependent_type_p (type))
12495 /* A functional cast has a list of operands. */
12496 expression = TREE_OPERAND (expression, 0);
12499 /* If there are no operands, it must be an expression such
12500 as "int()". This should not happen for aggregate types
12501 because it would form non-constant expressions. */
12502 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12507 if (TREE_CODE (expression) == TREE_LIST)
12509 for (; expression; expression = TREE_CHAIN (expression))
12510 if (value_dependent_expression_p (TREE_VALUE (expression)))
12515 return value_dependent_expression_p (expression);
12520 /* A `sizeof' expression is value-dependent if the operand is
12522 expression = TREE_OPERAND (expression, 0);
12523 if (TYPE_P (expression))
12524 return dependent_type_p (expression);
12525 return type_dependent_expression_p (expression);
12528 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12530 case COMPONENT_REF:
12531 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12532 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12535 /* A CALL_EXPR is value-dependent if any argument is
12536 value-dependent. Why do we have to handle CALL_EXPRs in this
12537 function at all? First, some function calls, those for which
12538 value_dependent_expression_p is true, man appear in constant
12539 expressions. Second, there appear to be bugs which result in
12540 other CALL_EXPRs reaching this point. */
12542 tree function = TREE_OPERAND (expression, 0);
12543 tree args = TREE_OPERAND (expression, 1);
12545 if (value_dependent_expression_p (function))
12551 if (TREE_CODE (args) == TREE_LIST)
12553 for (; args; args = TREE_CHAIN (args))
12554 if (value_dependent_expression_p (TREE_VALUE (args)))
12559 return value_dependent_expression_p (args);
12563 /* A constant expression is value-dependent if any subexpression is
12564 value-dependent. */
12565 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12567 case tcc_reference:
12569 return (value_dependent_expression_p
12570 (TREE_OPERAND (expression, 0)));
12572 case tcc_comparison:
12574 return ((value_dependent_expression_p
12575 (TREE_OPERAND (expression, 0)))
12576 || (value_dependent_expression_p
12577 (TREE_OPERAND (expression, 1))));
12579 case tcc_expression:
12582 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12583 /* In some cases, some of the operands may be missing.
12584 (For example, in the case of PREDECREMENT_EXPR, the
12585 amount to increment by may be missing.) That doesn't
12586 make the expression dependent. */
12587 if (TREE_OPERAND (expression, i)
12588 && (value_dependent_expression_p
12589 (TREE_OPERAND (expression, i))))
12599 /* The expression is not value-dependent. */
12603 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12604 [temp.dep.expr]. */
12607 type_dependent_expression_p (tree expression)
12609 if (!processing_template_decl)
12612 if (expression == error_mark_node)
12615 /* An unresolved name is always dependent. */
12616 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12619 /* Some expression forms are never type-dependent. */
12620 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12621 || TREE_CODE (expression) == SIZEOF_EXPR
12622 || TREE_CODE (expression) == ALIGNOF_EXPR
12623 || TREE_CODE (expression) == TYPEID_EXPR
12624 || TREE_CODE (expression) == DELETE_EXPR
12625 || TREE_CODE (expression) == VEC_DELETE_EXPR
12626 || TREE_CODE (expression) == THROW_EXPR)
12629 /* The types of these expressions depends only on the type to which
12630 the cast occurs. */
12631 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12632 || TREE_CODE (expression) == STATIC_CAST_EXPR
12633 || TREE_CODE (expression) == CONST_CAST_EXPR
12634 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12635 || TREE_CODE (expression) == CAST_EXPR)
12636 return dependent_type_p (TREE_TYPE (expression));
12638 /* The types of these expressions depends only on the type created
12639 by the expression. */
12640 if (TREE_CODE (expression) == NEW_EXPR
12641 || TREE_CODE (expression) == VEC_NEW_EXPR)
12643 /* For NEW_EXPR tree nodes created inside a template, either
12644 the object type itself or a TREE_LIST may appear as the
12646 tree type = TREE_OPERAND (expression, 1);
12647 if (TREE_CODE (type) == TREE_LIST)
12648 /* This is an array type. We need to check array dimensions
12650 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12651 || value_dependent_expression_p
12652 (TREE_OPERAND (TREE_VALUE (type), 1));
12654 return dependent_type_p (type);
12657 if (TREE_CODE (expression) == SCOPE_REF
12658 && dependent_scope_ref_p (expression,
12659 type_dependent_expression_p))
12662 if (TREE_CODE (expression) == FUNCTION_DECL
12663 && DECL_LANG_SPECIFIC (expression)
12664 && DECL_TEMPLATE_INFO (expression)
12665 && (any_dependent_template_arguments_p
12666 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12669 if (TREE_CODE (expression) == TEMPLATE_DECL
12670 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12673 if (TREE_TYPE (expression) == unknown_type_node)
12675 if (TREE_CODE (expression) == ADDR_EXPR)
12676 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12677 if (TREE_CODE (expression) == COMPONENT_REF
12678 || TREE_CODE (expression) == OFFSET_REF)
12680 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12682 expression = TREE_OPERAND (expression, 1);
12683 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12686 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12687 if (TREE_CODE (expression) == SCOPE_REF)
12690 if (TREE_CODE (expression) == BASELINK)
12691 expression = BASELINK_FUNCTIONS (expression);
12693 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12695 if (any_dependent_template_arguments_p
12696 (TREE_OPERAND (expression, 1)))
12698 expression = TREE_OPERAND (expression, 0);
12700 gcc_assert (TREE_CODE (expression) == OVERLOAD
12701 || TREE_CODE (expression) == FUNCTION_DECL);
12705 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12707 expression = OVL_NEXT (expression);
12712 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
12714 return (dependent_type_p (TREE_TYPE (expression)));
12717 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12718 contains a type-dependent expression. */
12721 any_type_dependent_arguments_p (tree args)
12725 tree arg = TREE_VALUE (args);
12727 if (type_dependent_expression_p (arg))
12729 args = TREE_CHAIN (args);
12734 /* Returns TRUE if the ARG (a template argument) is dependent. */
12737 dependent_template_arg_p (tree arg)
12739 if (!processing_template_decl)
12742 if (TREE_CODE (arg) == TEMPLATE_DECL
12743 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12744 return dependent_template_p (arg);
12745 else if (TYPE_P (arg))
12746 return dependent_type_p (arg);
12748 return (type_dependent_expression_p (arg)
12749 || value_dependent_expression_p (arg));
12752 /* Returns true if ARGS (a collection of template arguments) contains
12753 any dependent arguments. */
12756 any_dependent_template_arguments_p (tree args)
12763 if (args == error_mark_node)
12766 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12768 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12769 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12770 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12777 /* Returns TRUE if the template TMPL is dependent. */
12780 dependent_template_p (tree tmpl)
12782 if (TREE_CODE (tmpl) == OVERLOAD)
12786 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12788 tmpl = OVL_CHAIN (tmpl);
12793 /* Template template parameters are dependent. */
12794 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12795 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12797 /* So are names that have not been looked up. */
12798 if (TREE_CODE (tmpl) == SCOPE_REF
12799 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12801 /* So are member templates of dependent classes. */
12802 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12803 return dependent_type_p (DECL_CONTEXT (tmpl));
12807 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12810 dependent_template_id_p (tree tmpl, tree args)
12812 return (dependent_template_p (tmpl)
12813 || any_dependent_template_arguments_p (args));
12816 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12817 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12818 can be found. Note that this function peers inside uninstantiated
12819 templates and therefore should be used only in extremely limited
12820 situations. ONLY_CURRENT_P restricts this peering to the currently
12821 open classes hierarchy (which is required when comparing types). */
12824 resolve_typename_type (tree type, bool only_current_p)
12832 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12834 scope = TYPE_CONTEXT (type);
12835 name = TYPE_IDENTIFIER (type);
12837 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12838 it first before we can figure out what NAME refers to. */
12839 if (TREE_CODE (scope) == TYPENAME_TYPE)
12840 scope = resolve_typename_type (scope, only_current_p);
12841 /* If we don't know what SCOPE refers to, then we cannot resolve the
12843 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12844 return error_mark_node;
12845 /* If the SCOPE is a template type parameter, we have no way of
12846 resolving the name. */
12847 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12849 /* If the SCOPE is not the current instantiation, there's no reason
12850 to look inside it. */
12851 if (only_current_p && !currently_open_class (scope))
12852 return error_mark_node;
12853 /* If SCOPE is a partial instantiation, it will not have a valid
12854 TYPE_FIELDS list, so use the original template. */
12855 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12856 /* Enter the SCOPE so that name lookup will be resolved as if we
12857 were in the class definition. In particular, SCOPE will no
12858 longer be considered a dependent type. */
12859 pushed_scope = push_scope (scope);
12860 /* Look up the declaration. */
12861 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12862 /* Obtain the set of qualifiers applied to the TYPE. */
12863 quals = cp_type_quals (type);
12864 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12865 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12867 type = error_mark_node;
12868 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12869 && TREE_CODE (decl) == TYPE_DECL)
12870 type = TREE_TYPE (decl);
12871 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12872 && DECL_CLASS_TEMPLATE_P (decl))
12876 /* Obtain the template and the arguments. */
12877 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12878 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12879 /* Instantiate the template. */
12880 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12881 /*entering_scope=*/0, tf_error | tf_user);
12884 type = error_mark_node;
12885 /* Qualify the resulting type. */
12886 if (type != error_mark_node && quals)
12887 type = cp_build_qualified_type (type, quals);
12888 /* Leave the SCOPE. */
12890 pop_scope (pushed_scope);
12895 /* EXPR is an expression which is not type-dependent. Return a proxy
12896 for EXPR that can be used to compute the types of larger
12897 expressions containing EXPR. */
12900 build_non_dependent_expr (tree expr)
12904 /* Preserve null pointer constants so that the type of things like
12905 "p == 0" where "p" is a pointer can be determined. */
12906 if (null_ptr_cst_p (expr))
12908 /* Preserve OVERLOADs; the functions must be available to resolve
12911 if (TREE_CODE (inner_expr) == ADDR_EXPR)
12912 inner_expr = TREE_OPERAND (inner_expr, 0);
12913 if (TREE_CODE (inner_expr) == COMPONENT_REF)
12914 inner_expr = TREE_OPERAND (inner_expr, 1);
12915 if (is_overloaded_fn (inner_expr)
12916 || TREE_CODE (inner_expr) == OFFSET_REF)
12918 /* There is no need to return a proxy for a variable. */
12919 if (TREE_CODE (expr) == VAR_DECL)
12921 /* Preserve string constants; conversions from string constants to
12922 "char *" are allowed, even though normally a "const char *"
12923 cannot be used to initialize a "char *". */
12924 if (TREE_CODE (expr) == STRING_CST)
12926 /* Preserve arithmetic constants, as an optimization -- there is no
12927 reason to create a new node. */
12928 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12930 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12931 There is at least one place where we want to know that a
12932 particular expression is a throw-expression: when checking a ?:
12933 expression, there are special rules if the second or third
12934 argument is a throw-expression. */
12935 if (TREE_CODE (expr) == THROW_EXPR)
12938 if (TREE_CODE (expr) == COND_EXPR)
12939 return build3 (COND_EXPR,
12941 TREE_OPERAND (expr, 0),
12942 (TREE_OPERAND (expr, 1)
12943 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12944 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12945 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12946 if (TREE_CODE (expr) == COMPOUND_EXPR
12947 && !COMPOUND_EXPR_OVERLOADED (expr))
12948 return build2 (COMPOUND_EXPR,
12950 TREE_OPERAND (expr, 0),
12951 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12953 /* If the type is unknown, it can't really be non-dependent */
12954 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
12956 /* Otherwise, build a NON_DEPENDENT_EXPR.
12958 REFERENCE_TYPEs are not stripped for expressions in templates
12959 because doing so would play havoc with mangling. Consider, for
12962 template <typename T> void f<T& g>() { g(); }
12964 In the body of "f", the expression for "g" will have
12965 REFERENCE_TYPE, even though the standard says that it should
12966 not. The reason is that we must preserve the syntactic form of
12967 the expression so that mangling (say) "f<g>" inside the body of
12968 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12970 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12973 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12974 Return a new TREE_LIST with the various arguments replaced with
12975 equivalent non-dependent expressions. */
12978 build_non_dependent_args (tree args)
12983 new_args = NULL_TREE;
12984 for (a = args; a; a = TREE_CHAIN (a))
12985 new_args = tree_cons (NULL_TREE,
12986 build_non_dependent_expr (TREE_VALUE (a)),
12988 return nreverse (new_args);
12991 #include "gt-cp-pt.h"