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"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work.
56 The TREE_PURPOSE of each entry is either a DECL (for a function or
57 static data member), or a TYPE (for a class) indicating what we are
58 hoping to instantiate. The TREE_VALUE is not used. */
59 static GTY(()) tree pending_templates;
60 static GTY(()) tree last_pending_template;
62 int processing_template_parmlist;
63 static int template_header_count;
65 static GTY(()) tree saved_trees;
66 static GTY(()) varray_type inline_parm_levels;
67 static size_t inline_parm_levels_used;
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 void reopen_tinst_level (tree);
101 static tree classtype_mangled_name (tree);
102 static char* mangle_class_name_for_template (const char *, tree, tree);
103 static tree tsubst_initializer_list (tree, tree);
104 static tree get_class_bindings (tree, tree, tree);
105 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
106 static void tsubst_enum (tree, tree, tree);
107 static tree add_to_template_args (tree, tree);
108 static tree add_outermost_template_args (tree, tree);
109 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
110 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
111 static int type_unification_real (tree, tree, tree, tree,
112 int, unification_kind_t, int);
113 static void note_template_header (int);
114 static tree convert_nontype_argument_function (tree, tree);
115 static tree convert_nontype_argument (tree, tree);
116 static tree convert_template_argument (tree, tree, tree,
117 tsubst_flags_t, int, tree);
118 static int for_each_template_parm (tree, tree_fn_t, void*,
119 struct pointer_set_t*);
120 static tree build_template_parm_index (int, int, int, tree, tree);
121 static int inline_needs_template_parms (tree);
122 static void push_inline_template_parms_recursive (tree, int);
123 static tree retrieve_local_specialization (tree);
124 static void register_local_specialization (tree, tree);
125 static tree reduce_template_parm_level (tree, tree, int);
126 static int mark_template_parm (tree, void *);
127 static int template_parm_this_level_p (tree, void *);
128 static tree tsubst_friend_function (tree, tree);
129 static tree tsubst_friend_class (tree, tree);
130 static int can_complete_type_without_circularity (tree);
131 static tree get_bindings (tree, tree, tree, bool);
132 static int template_decl_level (tree);
133 static int check_cv_quals_for_unify (int, tree, tree);
134 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
135 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
136 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
137 static void regenerate_decl_from_template (tree, tree);
138 static tree most_specialized_class (tree, tree);
139 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
140 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
141 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
142 static void check_specialization_scope (void);
143 static tree process_partial_specialization (tree);
144 static void set_current_access_from_decl (tree);
145 static void check_default_tmpl_args (tree, tree, int, int);
146 static tree get_template_base (tree, tree, tree, tree);
147 static int verify_class_unification (tree, tree, tree);
148 static tree try_class_unification (tree, tree, tree, tree);
149 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
151 static tree determine_specialization (tree, tree, tree *, int, int);
152 static int template_args_equal (tree, tree);
153 static void tsubst_default_arguments (tree);
154 static tree for_each_template_parm_r (tree *, int *, void *);
155 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
156 static void copy_default_args_to_explicit_spec (tree);
157 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
158 static int eq_local_specializations (const void *, const void *);
159 static bool dependent_type_p_r (tree);
160 static tree tsubst (tree, tree, tsubst_flags_t, tree);
161 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
162 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
164 /* Make the current scope suitable for access checking when we are
165 processing T. T can be FUNCTION_DECL for instantiated function
166 template, or VAR_DECL for static member variable (need by
167 instantiate_decl). */
170 push_access_scope (tree t)
172 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
173 || TREE_CODE (t) == VAR_DECL);
175 if (DECL_FRIEND_CONTEXT (t))
176 push_nested_class (DECL_FRIEND_CONTEXT (t));
177 else if (DECL_CLASS_SCOPE_P (t))
178 push_nested_class (DECL_CONTEXT (t));
180 push_to_top_level ();
182 if (TREE_CODE (t) == FUNCTION_DECL)
184 saved_access_scope = tree_cons
185 (NULL_TREE, current_function_decl, saved_access_scope);
186 current_function_decl = t;
190 /* Restore the scope set up by push_access_scope. T is the node we
194 pop_access_scope (tree t)
196 if (TREE_CODE (t) == FUNCTION_DECL)
198 current_function_decl = TREE_VALUE (saved_access_scope);
199 saved_access_scope = TREE_CHAIN (saved_access_scope);
202 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
205 pop_from_top_level ();
208 /* Do any processing required when DECL (a member template
209 declaration) is finished. Returns the TEMPLATE_DECL corresponding
210 to DECL, unless it is a specialization, in which case the DECL
211 itself is returned. */
214 finish_member_template_decl (tree decl)
216 if (decl == error_mark_node)
217 return error_mark_node;
219 gcc_assert (DECL_P (decl));
221 if (TREE_CODE (decl) == TYPE_DECL)
225 type = TREE_TYPE (decl);
226 if (IS_AGGR_TYPE (type)
227 && CLASSTYPE_TEMPLATE_INFO (type)
228 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
230 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
231 check_member_template (tmpl);
236 else if (TREE_CODE (decl) == FIELD_DECL)
237 error ("data member %qD cannot be a member template", decl);
238 else if (DECL_TEMPLATE_INFO (decl))
240 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
242 check_member_template (DECL_TI_TEMPLATE (decl));
243 return DECL_TI_TEMPLATE (decl);
249 error ("invalid member template declaration %qD", decl);
251 return error_mark_node;
254 /* Returns the template nesting level of the indicated class TYPE.
264 A<T>::B<U> has depth two, while A<T> has depth one.
265 Both A<T>::B<int> and A<int>::B<U> have depth one, if
266 they are instantiations, not specializations.
268 This function is guaranteed to return 0 if passed NULL_TREE so
269 that, for example, `template_class_depth (current_class_type)' is
273 template_class_depth (tree type)
278 type && TREE_CODE (type) != NAMESPACE_DECL;
279 type = (TREE_CODE (type) == FUNCTION_DECL)
280 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
282 if (TREE_CODE (type) != FUNCTION_DECL)
284 if (CLASSTYPE_TEMPLATE_INFO (type)
285 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
286 && uses_template_parms (CLASSTYPE_TI_ARGS (type)))
291 if (DECL_TEMPLATE_INFO (type)
292 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
293 && uses_template_parms (DECL_TI_ARGS (type)))
301 /* Returns 1 if processing DECL as part of do_pending_inlines
302 needs us to push template parms. */
305 inline_needs_template_parms (tree decl)
307 if (! DECL_TEMPLATE_INFO (decl))
310 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
311 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
314 /* Subroutine of maybe_begin_member_template_processing.
315 Push the template parms in PARMS, starting from LEVELS steps into the
316 chain, and ending at the beginning, since template parms are listed
320 push_inline_template_parms_recursive (tree parmlist, int levels)
322 tree parms = TREE_VALUE (parmlist);
326 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
328 ++processing_template_decl;
329 current_template_parms
330 = tree_cons (size_int (processing_template_decl),
331 parms, current_template_parms);
332 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
334 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
336 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
338 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
339 gcc_assert (DECL_P (parm));
341 switch (TREE_CODE (parm))
350 /* Make a CONST_DECL as is done in process_template_parm.
351 It is ugly that we recreate this here; the original
352 version built in process_template_parm is no longer
354 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
356 DECL_ARTIFICIAL (decl) = 1;
357 TREE_CONSTANT (decl) = 1;
358 TREE_INVARIANT (decl) = 1;
359 TREE_READONLY (decl) = 1;
360 DECL_INITIAL (decl) = DECL_INITIAL (parm);
361 SET_DECL_TEMPLATE_PARM_P (decl);
372 /* Restore the template parameter context for a member template or
373 a friend template defined in a class definition. */
376 maybe_begin_member_template_processing (tree decl)
381 if (inline_needs_template_parms (decl))
383 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
384 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
386 if (DECL_TEMPLATE_SPECIALIZATION (decl))
389 parms = TREE_CHAIN (parms);
392 push_inline_template_parms_recursive (parms, levels);
395 /* Remember how many levels of template parameters we pushed so that
396 we can pop them later. */
397 if (!inline_parm_levels)
398 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
399 if (inline_parm_levels_used == inline_parm_levels->num_elements)
400 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
401 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
402 ++inline_parm_levels_used;
405 /* Undo the effects of maybe_begin_member_template_processing. */
408 maybe_end_member_template_processing (void)
412 if (!inline_parm_levels_used)
415 --inline_parm_levels_used;
417 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
420 --processing_template_decl;
421 current_template_parms = TREE_CHAIN (current_template_parms);
426 /* Return a new template argument vector which contains all of ARGS,
427 but has as its innermost set of arguments the EXTRA_ARGS. */
430 add_to_template_args (tree args, tree extra_args)
437 extra_depth = TMPL_ARGS_DEPTH (extra_args);
438 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
440 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
441 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
443 for (j = 1; j <= extra_depth; ++j, ++i)
444 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
449 /* Like add_to_template_args, but only the outermost ARGS are added to
450 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
451 (EXTRA_ARGS) levels are added. This function is used to combine
452 the template arguments from a partial instantiation with the
453 template arguments used to attain the full instantiation from the
454 partial instantiation. */
457 add_outermost_template_args (tree args, tree extra_args)
461 /* If there are more levels of EXTRA_ARGS than there are ARGS,
462 something very fishy is going on. */
463 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
465 /* If *all* the new arguments will be the EXTRA_ARGS, just return
467 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
470 /* For the moment, we make ARGS look like it contains fewer levels. */
471 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
473 new_args = add_to_template_args (args, extra_args);
475 /* Now, we restore ARGS to its full dimensions. */
476 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
481 /* Return the N levels of innermost template arguments from the ARGS. */
484 get_innermost_template_args (tree args, int n)
492 /* If N is 1, just return the innermost set of template arguments. */
494 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
496 /* If we're not removing anything, just return the arguments we were
498 extra_levels = TMPL_ARGS_DEPTH (args) - n;
499 gcc_assert (extra_levels >= 0);
500 if (extra_levels == 0)
503 /* Make a new set of arguments, not containing the outer arguments. */
504 new_args = make_tree_vec (n);
505 for (i = 1; i <= n; ++i)
506 SET_TMPL_ARGS_LEVEL (new_args, i,
507 TMPL_ARGS_LEVEL (args, i + extra_levels));
512 /* We've got a template header coming up; push to a new level for storing
516 begin_template_parm_list (void)
518 /* We use a non-tag-transparent scope here, which causes pushtag to
519 put tags in this scope, rather than in the enclosing class or
520 namespace scope. This is the right thing, since we want
521 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
522 global template class, push_template_decl handles putting the
523 TEMPLATE_DECL into top-level scope. For a nested template class,
526 template <class T> struct S1 {
527 template <class T> struct S2 {};
530 pushtag contains special code to call pushdecl_with_scope on the
531 TEMPLATE_DECL for S2. */
532 begin_scope (sk_template_parms, NULL);
533 ++processing_template_decl;
534 ++processing_template_parmlist;
535 note_template_header (0);
538 /* This routine is called when a specialization is declared. If it is
539 invalid to declare a specialization here, an error is reported. */
542 check_specialization_scope (void)
544 tree scope = current_scope ();
548 An explicit specialization shall be declared in the namespace of
549 which the template is a member, or, for member templates, in the
550 namespace of which the enclosing class or enclosing class
551 template is a member. An explicit specialization of a member
552 function, member class or static data member of a class template
553 shall be declared in the namespace of which the class template
555 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
556 error ("explicit specialization in non-namespace scope %qD", scope);
560 In an explicit specialization declaration for a member of a class
561 template or a member template that appears in namespace scope,
562 the member template and some of its enclosing class templates may
563 remain unspecialized, except that the declaration shall not
564 explicitly specialize a class member template if its enclosing
565 class templates are not explicitly specialized as well. */
566 if (current_template_parms)
567 error ("enclosing class templates are not explicitly specialized");
570 /* We've just seen template <>. */
573 begin_specialization (void)
575 begin_scope (sk_template_spec, NULL);
576 note_template_header (1);
577 check_specialization_scope ();
580 /* Called at then end of processing a declaration preceded by
584 end_specialization (void)
587 reset_specialization ();
590 /* Any template <>'s that we have seen thus far are not referring to a
591 function specialization. */
594 reset_specialization (void)
596 processing_specialization = 0;
597 template_header_count = 0;
600 /* We've just seen a template header. If SPECIALIZATION is nonzero,
601 it was of the form template <>. */
604 note_template_header (int specialization)
606 processing_specialization = specialization;
607 template_header_count++;
610 /* We're beginning an explicit instantiation. */
613 begin_explicit_instantiation (void)
615 gcc_assert (!processing_explicit_instantiation);
616 processing_explicit_instantiation = true;
621 end_explicit_instantiation (void)
623 gcc_assert (processing_explicit_instantiation);
624 processing_explicit_instantiation = false;
627 /* An explicit specialization or partial specialization TMPL is being
628 declared. Check that the namespace in which the specialization is
629 occurring is permissible. Returns false iff it is invalid to
630 specialize TMPL in the current namespace. */
633 check_specialization_namespace (tree tmpl)
635 tree tpl_ns = decl_namespace_context (tmpl);
639 An explicit specialization shall be declared in the namespace of
640 which the template is a member, or, for member templates, in the
641 namespace of which the enclosing class or enclosing class
642 template is a member. An explicit specialization of a member
643 function, member class or static data member of a class template
644 shall be declared in the namespace of which the class template is
646 if (is_associated_namespace (current_namespace, tpl_ns))
647 /* Same or super-using namespace. */
651 pedwarn ("specialization of %qD in different namespace", tmpl);
652 pedwarn (" from definition of %q+#D", tmpl);
657 /* SPEC is an explicit instantiation. Check that it is valid to
658 perform this explicit instantiation in the current namespace. */
661 check_explicit_instantiation_namespace (tree spec)
665 /* DR 275: An explicit instantiation shall appear in an enclosing
666 namespace of its template. */
667 ns = decl_namespace_context (spec);
668 if (!is_ancestor (current_namespace, ns))
669 pedwarn ("explicit instantiation of %qD in namespace %qD "
670 "(which does not enclose namespace %qD)",
671 spec, current_namespace, ns);
674 /* The TYPE is being declared. If it is a template type, that means it
675 is a partial specialization. Do appropriate error-checking. */
678 maybe_process_partial_specialization (tree type)
682 if (type == error_mark_node)
685 context = TYPE_CONTEXT (type);
687 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
689 /* This is for ordinary explicit specialization and partial
690 specialization of a template class such as:
692 template <> class C<int>;
696 template <class T> class C<T*>;
698 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
700 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
701 && !COMPLETE_TYPE_P (type))
703 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
704 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
705 if (processing_template_decl)
706 push_template_decl (TYPE_MAIN_DECL (type));
708 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
709 error ("specialization of %qT after instantiation", type);
711 else if (CLASS_TYPE_P (type)
712 && !CLASSTYPE_USE_TEMPLATE (type)
713 && CLASSTYPE_TEMPLATE_INFO (type)
714 && context && CLASS_TYPE_P (context)
715 && CLASSTYPE_TEMPLATE_INFO (context))
717 /* This is for an explicit specialization of member class
718 template according to [temp.expl.spec/18]:
720 template <> template <class U> class C<int>::D;
722 The context `C<int>' must be an implicit instantiation.
723 Otherwise this is just a member class template declared
726 template <> class C<int> { template <class U> class D; };
727 template <> template <class U> class C<int>::D;
729 In the first case, `C<int>::D' is a specialization of `C<T>::D'
730 while in the second case, `C<int>::D' is a primary template
731 and `C<T>::D' may not exist. */
733 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
734 && !COMPLETE_TYPE_P (type))
738 if (current_namespace
739 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
741 pedwarn ("specializing %q#T in different namespace", type);
742 pedwarn (" from definition of %q+#D",
743 CLASSTYPE_TI_TEMPLATE (type));
746 /* Check for invalid specialization after instantiation:
748 template <> template <> class C<int>::D<int>;
749 template <> template <class U> class C<int>::D; */
751 for (t = DECL_TEMPLATE_INSTANTIATIONS
752 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
753 t; t = TREE_CHAIN (t))
754 if (TREE_VALUE (t) != type
755 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
756 error ("specialization %qT after instantiation %qT",
757 type, TREE_VALUE (t));
759 /* Mark TYPE as a specialization. And as a result, we only
760 have one level of template argument for the innermost
762 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
763 CLASSTYPE_TI_ARGS (type)
764 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
767 else if (processing_specialization)
768 error ("explicit specialization of non-template %qT", type);
771 /* Returns nonzero if we can optimize the retrieval of specializations
772 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
773 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
776 optimize_specialization_lookup_p (tree tmpl)
778 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
779 && DECL_CLASS_SCOPE_P (tmpl)
780 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
782 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
783 /* The optimized lookup depends on the fact that the
784 template arguments for the member function template apply
785 purely to the containing class, which is not true if the
786 containing class is an explicit or partial
788 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
789 && !DECL_MEMBER_TEMPLATE_P (tmpl)
790 && !DECL_CONV_FN_P (tmpl)
791 /* It is possible to have a template that is not a member
792 template and is not a member of a template class:
794 template <typename T>
795 struct S { friend A::f(); };
797 Here, the friend function is a template, but the context does
798 not have template information. The optimized lookup relies
799 on having ARGS be the template arguments for both the class
800 and the function template. */
801 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
804 /* Retrieve the specialization (in the sense of [temp.spec] - a
805 specialization is either an instantiation or an explicit
806 specialization) of TMPL for the given template ARGS. If there is
807 no such specialization, return NULL_TREE. The ARGS are a vector of
808 arguments, or a vector of vectors of arguments, in the case of
809 templates with more than one level of parameters.
811 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
812 then we search for a partial specialization matching ARGS. This
813 parameter is ignored if TMPL is not a class template. */
816 retrieve_specialization (tree tmpl, tree args,
817 bool class_specializations_p)
819 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
821 /* There should be as many levels of arguments as there are
822 levels of parameters. */
823 gcc_assert (TMPL_ARGS_DEPTH (args)
824 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
826 if (optimize_specialization_lookup_p (tmpl))
829 tree class_specialization;
830 VEC(tree,gc) *methods;
834 /* The template arguments actually apply to the containing
835 class. Find the class specialization with those
837 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
839 = retrieve_specialization (class_template, args,
840 /*class_specializations_p=*/false);
841 if (!class_specialization)
843 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
844 for the specialization. */
845 idx = class_method_index_for_fn (class_specialization, tmpl);
848 /* Iterate through the methods with the indicated name, looking
849 for the one that has an instance of TMPL. */
850 methods = CLASSTYPE_METHOD_VEC (class_specialization);
851 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
853 tree fn = OVL_CURRENT (fns);
854 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
864 /* Class templates store their instantiations on the
865 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
866 DECL_TEMPLATE_SPECIALIZATIONS list. */
867 if (!class_specializations_p
868 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
869 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
871 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
873 /* Iterate through the list until we find a matching template. */
874 while (*sp != NULL_TREE)
878 if (comp_template_args (TREE_PURPOSE (spec), args))
880 /* Use the move-to-front heuristic to speed up future
884 *sp = TREE_CHAIN (*sp);
885 TREE_CHAIN (spec) = *head;
888 return TREE_VALUE (spec);
890 sp = &TREE_CHAIN (spec);
897 /* Like retrieve_specialization, but for local declarations. */
900 retrieve_local_specialization (tree tmpl)
902 tree spec = (tree) htab_find_with_hash (local_specializations, tmpl,
903 htab_hash_pointer (tmpl));
904 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
907 /* Returns nonzero iff DECL is a specialization of TMPL. */
910 is_specialization_of (tree decl, tree tmpl)
914 if (TREE_CODE (decl) == FUNCTION_DECL)
918 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
924 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
926 for (t = TREE_TYPE (decl);
928 t = CLASSTYPE_USE_TEMPLATE (t)
929 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
930 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
937 /* Returns nonzero iff DECL is a specialization of friend declaration
938 FRIEND according to [temp.friend]. */
941 is_specialization_of_friend (tree decl, tree friend)
943 bool need_template = true;
946 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
947 || TREE_CODE (decl) == TYPE_DECL);
949 /* For [temp.friend/6] when FRIEND is an ordinary member function
950 of a template class, we want to check if DECL is a specialization
952 if (TREE_CODE (friend) == FUNCTION_DECL
953 && DECL_TEMPLATE_INFO (friend)
954 && !DECL_USE_TEMPLATE (friend))
956 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
957 friend = DECL_TI_TEMPLATE (friend);
958 need_template = false;
960 else if (TREE_CODE (friend) == TEMPLATE_DECL
961 && !PRIMARY_TEMPLATE_P (friend))
962 need_template = false;
964 /* There is nothing to do if this is not a template friend. */
965 if (TREE_CODE (friend) != TEMPLATE_DECL)
968 if (is_specialization_of (decl, friend))
972 A member of a class template may be declared to be a friend of a
973 non-template class. In this case, the corresponding member of
974 every specialization of the class template is a friend of the
975 class granting friendship.
977 For example, given a template friend declaration
979 template <class T> friend void A<T>::f();
981 the member function below is considered a friend
983 template <> struct A<int> {
987 For this type of template friend, TEMPLATE_DEPTH below will be
988 nonzero. To determine if DECL is a friend of FRIEND, we first
989 check if the enclosing class is a specialization of another. */
991 template_depth = template_class_depth (DECL_CONTEXT (friend));
993 && DECL_CLASS_SCOPE_P (decl)
994 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
995 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
997 /* Next, we check the members themselves. In order to handle
998 a few tricky cases, such as when FRIEND's are
1000 template <class T> friend void A<T>::g(T t);
1001 template <class T> template <T t> friend void A<T>::h();
1005 void A<int>::g(int);
1006 template <int> void A<int>::h();
1008 we need to figure out ARGS, the template arguments from
1009 the context of DECL. This is required for template substitution
1010 of `T' in the function parameter of `g' and template parameter
1011 of `h' in the above examples. Here ARGS corresponds to `int'. */
1013 tree context = DECL_CONTEXT (decl);
1014 tree args = NULL_TREE;
1015 int current_depth = 0;
1017 while (current_depth < template_depth)
1019 if (CLASSTYPE_TEMPLATE_INFO (context))
1021 if (current_depth == 0)
1022 args = TYPE_TI_ARGS (context);
1024 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1027 context = TYPE_CONTEXT (context);
1030 if (TREE_CODE (decl) == FUNCTION_DECL)
1035 tree friend_args_type;
1036 tree decl_args_type;
1038 /* Make sure that both DECL and FRIEND are templates or
1040 is_template = DECL_TEMPLATE_INFO (decl)
1041 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1042 if (need_template ^ is_template)
1044 else if (is_template)
1046 /* If both are templates, check template parameter list. */
1048 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1050 if (!comp_template_parms
1051 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1055 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1058 decl_type = TREE_TYPE (decl);
1060 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1061 tf_none, NULL_TREE);
1062 if (friend_type == error_mark_node)
1065 /* Check if return types match. */
1066 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1069 /* Check if function parameter types match, ignoring the
1070 `this' parameter. */
1071 friend_args_type = TYPE_ARG_TYPES (friend_type);
1072 decl_args_type = TYPE_ARG_TYPES (decl_type);
1073 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1074 friend_args_type = TREE_CHAIN (friend_args_type);
1075 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1076 decl_args_type = TREE_CHAIN (decl_args_type);
1078 return compparms (decl_args_type, friend_args_type);
1082 /* DECL is a TYPE_DECL */
1084 tree decl_type = TREE_TYPE (decl);
1086 /* Make sure that both DECL and FRIEND are templates or
1089 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1090 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1092 if (need_template ^ is_template)
1094 else if (is_template)
1097 /* If both are templates, check the name of the two
1098 TEMPLATE_DECL's first because is_friend didn't. */
1099 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1100 != DECL_NAME (friend))
1103 /* Now check template parameter list. */
1105 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1107 return comp_template_parms
1108 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1112 return (DECL_NAME (decl)
1113 == DECL_NAME (friend));
1119 /* Register the specialization SPEC as a specialization of TMPL with
1120 the indicated ARGS. IS_FRIEND indicates whether the specialization
1121 is actually just a friend declaration. Returns SPEC, or an
1122 equivalent prior declaration, if available. */
1125 register_specialization (tree spec, tree tmpl, tree args, bool is_friend)
1129 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1131 if (TREE_CODE (spec) == FUNCTION_DECL
1132 && uses_template_parms (DECL_TI_ARGS (spec)))
1133 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1134 register it; we want the corresponding TEMPLATE_DECL instead.
1135 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1136 the more obvious `uses_template_parms (spec)' to avoid problems
1137 with default function arguments. In particular, given
1138 something like this:
1140 template <class T> void f(T t1, T t = T())
1142 the default argument expression is not substituted for in an
1143 instantiation unless and until it is actually needed. */
1146 fn = retrieve_specialization (tmpl, args,
1147 /*class_specializations_p=*/false);
1148 /* We can sometimes try to re-register a specialization that we've
1149 already got. In particular, regenerate_decl_from_template calls
1150 duplicate_decls which will update the specialization list. But,
1151 we'll still get called again here anyhow. It's more convenient
1152 to simply allow this than to try to prevent it. */
1155 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1157 if (DECL_TEMPLATE_INSTANTIATION (fn))
1160 || DECL_EXPLICIT_INSTANTIATION (fn))
1162 error ("specialization of %qD after instantiation",
1169 /* This situation should occur only if the first
1170 specialization is an implicit instantiation, the
1171 second is an explicit specialization, and the
1172 implicit instantiation has not yet been used. That
1173 situation can occur if we have implicitly
1174 instantiated a member function and then specialized
1177 We can also wind up here if a friend declaration that
1178 looked like an instantiation turns out to be a
1181 template <class T> void foo(T);
1182 class S { friend void foo<>(int) };
1183 template <> void foo(int);
1185 We transform the existing DECL in place so that any
1186 pointers to it become pointers to the updated
1189 If there was a definition for the template, but not
1190 for the specialization, we want this to look as if
1191 there were no definition, and vice versa. */
1192 DECL_INITIAL (fn) = NULL_TREE;
1193 duplicate_decls (spec, fn, is_friend);
1194 /* The call to duplicate_decls will have applied
1197 An explicit specialization of a function template
1198 is inline only if it is explicitly declared to be,
1199 and independently of whether its function template
1202 to the primary function; now copy the inline bits to
1203 the various clones. */
1204 FOR_EACH_CLONE (clone, fn)
1206 DECL_DECLARED_INLINE_P (clone)
1207 = DECL_DECLARED_INLINE_P (fn);
1211 check_specialization_namespace (fn);
1216 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1218 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1219 /* Dup decl failed, but this is a new definition. Set the
1220 line number so any errors match this new
1222 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1228 /* A specialization must be declared in the same namespace as the
1229 template it is specializing. */
1230 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1231 && !check_specialization_namespace (tmpl))
1232 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1234 if (!optimize_specialization_lookup_p (tmpl))
1235 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1236 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1241 /* Unregister the specialization SPEC as a specialization of TMPL.
1242 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1243 if the SPEC was listed as a specialization of TMPL. */
1246 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1250 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1252 s = &TREE_CHAIN (*s))
1253 if (TREE_VALUE (*s) == spec)
1256 *s = TREE_CHAIN (*s);
1258 TREE_VALUE (*s) = new_spec;
1265 /* Compare an entry in the local specializations hash table P1 (which
1266 is really a pointer to a TREE_LIST) with P2 (which is really a
1270 eq_local_specializations (const void *p1, const void *p2)
1272 return TREE_VALUE ((tree) p1) == (tree) p2;
1275 /* Hash P1, an entry in the local specializations table. */
1278 hash_local_specialization (const void* p1)
1280 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1283 /* Like register_specialization, but for local declarations. We are
1284 registering SPEC, an instantiation of TMPL. */
1287 register_local_specialization (tree spec, tree tmpl)
1291 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1292 htab_hash_pointer (tmpl), INSERT);
1293 *slot = build_tree_list (spec, tmpl);
1296 /* Print the list of candidate FNS in an error message. */
1299 print_candidates (tree fns)
1303 const char *str = "candidates are:";
1305 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1309 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1310 error ("%s %+#D", str, OVL_CURRENT (f));
1315 /* Returns the template (one of the functions given by TEMPLATE_ID)
1316 which can be specialized to match the indicated DECL with the
1317 explicit template args given in TEMPLATE_ID. The DECL may be
1318 NULL_TREE if none is available. In that case, the functions in
1319 TEMPLATE_ID are non-members.
1321 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1322 specialization of a member template.
1324 The TEMPLATE_COUNT is the number of references to qualifying
1325 template classes that appeared in the name of the function. See
1326 check_explicit_specialization for a more accurate description.
1328 The template args (those explicitly specified and those deduced)
1329 are output in a newly created vector *TARGS_OUT.
1331 If it is impossible to determine the result, an error message is
1332 issued. The error_mark_node is returned to indicate failure. */
1335 determine_specialization (tree template_id,
1338 int need_member_template,
1343 tree explicit_targs;
1344 tree candidates = NULL_TREE;
1345 /* A TREE_LIST of templates of which DECL may be a specialization.
1346 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1347 corresponding TREE_PURPOSE is the set of template arguments that,
1348 when used to instantiate the template, would produce a function
1349 with the signature of DECL. */
1350 tree templates = NULL_TREE;
1352 struct cp_binding_level *b;
1354 *targs_out = NULL_TREE;
1356 if (template_id == error_mark_node)
1357 return error_mark_node;
1359 fns = TREE_OPERAND (template_id, 0);
1360 explicit_targs = TREE_OPERAND (template_id, 1);
1362 if (fns == error_mark_node)
1363 return error_mark_node;
1365 /* Check for baselinks. */
1366 if (BASELINK_P (fns))
1367 fns = BASELINK_FUNCTIONS (fns);
1369 if (!is_overloaded_fn (fns))
1371 error ("%qD is not a function template", fns);
1372 return error_mark_node;
1375 /* Count the number of template headers specified for this
1378 for (b = current_binding_level;
1379 b->kind == sk_template_parms;
1383 for (; fns; fns = OVL_NEXT (fns))
1385 tree fn = OVL_CURRENT (fns);
1387 if (TREE_CODE (fn) == TEMPLATE_DECL)
1389 tree decl_arg_types;
1392 /* DECL might be a specialization of FN. */
1394 /* Adjust the type of DECL in case FN is a static member. */
1395 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1396 if (DECL_STATIC_FUNCTION_P (fn)
1397 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1398 decl_arg_types = TREE_CHAIN (decl_arg_types);
1400 /* Check that the number of function parameters matches.
1402 template <class T> void f(int i = 0);
1403 template <> void f<int>();
1404 The specialization f<int> is invalid but is not caught
1405 by get_bindings below. */
1407 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1408 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1411 /* For a non-static member function, we need to make sure that
1412 the const qualification is the same. This can be done by
1413 checking the 'this' in the argument list. */
1414 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1415 && !same_type_p (TREE_VALUE (fn_arg_types),
1416 TREE_VALUE (decl_arg_types)))
1419 /* In case of explicit specialization, we need to check if
1420 the number of template headers appearing in the specialization
1421 is correct. This is usually done in check_explicit_specialization,
1422 but the check done there cannot be exhaustive when specializing
1423 member functions. Consider the following code:
1425 template <> void A<int>::f(int);
1426 template <> template <> void A<int>::f(int);
1428 Assuming that A<int> is not itself an explicit specialization
1429 already, the first line specializes "f" which is a non-template
1430 member function, whilst the second line specializes "f" which
1431 is a template member function. So both lines are syntactically
1432 correct, and check_explicit_specialization does not reject
1435 Here, we can do better, as we are matching the specialization
1436 against the declarations. We count the number of template
1437 headers, and we check if they match TEMPLATE_COUNT + 1
1438 (TEMPLATE_COUNT is the number of qualifying template classes,
1439 plus there must be another header for the member template
1442 Notice that if header_count is zero, this is not a
1443 specialization but rather a template instantiation, so there
1444 is no check we can perform here. */
1445 if (header_count && header_count != template_count + 1)
1448 /* Check that the number of template arguments at the
1449 innermost level for DECL is the same as for FN. */
1450 if (current_binding_level->kind == sk_template_parms
1451 && !current_binding_level->explicit_spec_p
1452 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1453 != TREE_VEC_LENGTH (TREE_VALUE (current_template_parms))))
1456 /* See whether this function might be a specialization of this
1458 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1461 /* We cannot deduce template arguments that when used to
1462 specialize TMPL will produce DECL. */
1465 /* Save this template, and the arguments deduced. */
1466 templates = tree_cons (targs, fn, templates);
1468 else if (need_member_template)
1469 /* FN is an ordinary member function, and we need a
1470 specialization of a member template. */
1472 else if (TREE_CODE (fn) != FUNCTION_DECL)
1473 /* We can get IDENTIFIER_NODEs here in certain erroneous
1476 else if (!DECL_FUNCTION_MEMBER_P (fn))
1477 /* This is just an ordinary non-member function. Nothing can
1478 be a specialization of that. */
1480 else if (DECL_ARTIFICIAL (fn))
1481 /* Cannot specialize functions that are created implicitly. */
1485 tree decl_arg_types;
1487 /* This is an ordinary member function. However, since
1488 we're here, we can assume it's enclosing class is a
1489 template class. For example,
1491 template <typename T> struct S { void f(); };
1492 template <> void S<int>::f() {}
1494 Here, S<int>::f is a non-template, but S<int> is a
1495 template class. If FN has the same type as DECL, we
1496 might be in business. */
1498 if (!DECL_TEMPLATE_INFO (fn))
1499 /* Its enclosing class is an explicit specialization
1500 of a template class. This is not a candidate. */
1503 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1504 TREE_TYPE (TREE_TYPE (fn))))
1505 /* The return types differ. */
1508 /* Adjust the type of DECL in case FN is a static member. */
1509 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1510 if (DECL_STATIC_FUNCTION_P (fn)
1511 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1512 decl_arg_types = TREE_CHAIN (decl_arg_types);
1514 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1517 candidates = tree_cons (NULL_TREE, fn, candidates);
1521 if (templates && TREE_CHAIN (templates))
1527 It is possible for a specialization with a given function
1528 signature to be instantiated from more than one function
1529 template. In such cases, explicit specification of the
1530 template arguments must be used to uniquely identify the
1531 function template specialization being specialized.
1533 Note that here, there's no suggestion that we're supposed to
1534 determine which of the candidate templates is most
1535 specialized. However, we, also have:
1539 Partial ordering of overloaded function template
1540 declarations is used in the following contexts to select
1541 the function template to which a function template
1542 specialization refers:
1544 -- when an explicit specialization refers to a function
1547 So, we do use the partial ordering rules, at least for now.
1548 This extension can only serve to make invalid programs valid,
1549 so it's safe. And, there is strong anecdotal evidence that
1550 the committee intended the partial ordering rules to apply;
1551 the EDG front-end has that behavior, and John Spicer claims
1552 that the committee simply forgot to delete the wording in
1553 [temp.expl.spec]. */
1554 tree tmpl = most_specialized_instantiation (templates);
1555 if (tmpl != error_mark_node)
1558 TREE_CHAIN (templates) = NULL_TREE;
1562 if (templates == NULL_TREE && candidates == NULL_TREE)
1564 error ("template-id %qD for %q+D does not match any template "
1565 "declaration", template_id, decl);
1566 return error_mark_node;
1568 else if ((templates && TREE_CHAIN (templates))
1569 || (candidates && TREE_CHAIN (candidates))
1570 || (templates && candidates))
1572 error ("ambiguous template specialization %qD for %q+D",
1574 chainon (candidates, templates);
1575 print_candidates (candidates);
1576 return error_mark_node;
1579 /* We have one, and exactly one, match. */
1582 /* It was a specialization of an ordinary member function in a
1584 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1585 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1588 /* It was a specialization of a template. */
1589 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1590 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1592 *targs_out = copy_node (targs);
1593 SET_TMPL_ARGS_LEVEL (*targs_out,
1594 TMPL_ARGS_DEPTH (*targs_out),
1595 TREE_PURPOSE (templates));
1598 *targs_out = TREE_PURPOSE (templates);
1599 return TREE_VALUE (templates);
1602 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1603 but with the default argument values filled in from those in the
1607 copy_default_args_to_explicit_spec_1 (tree spec_types,
1610 tree new_spec_types;
1615 if (spec_types == void_list_node)
1616 return void_list_node;
1618 /* Substitute into the rest of the list. */
1620 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1621 TREE_CHAIN (tmpl_types));
1623 /* Add the default argument for this parameter. */
1624 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1625 TREE_VALUE (spec_types),
1629 /* DECL is an explicit specialization. Replicate default arguments
1630 from the template it specializes. (That way, code like:
1632 template <class T> void f(T = 3);
1633 template <> void f(double);
1636 works, as required.) An alternative approach would be to look up
1637 the correct default arguments at the call-site, but this approach
1638 is consistent with how implicit instantiations are handled. */
1641 copy_default_args_to_explicit_spec (tree decl)
1646 tree new_spec_types;
1650 tree object_type = NULL_TREE;
1651 tree in_charge = NULL_TREE;
1652 tree vtt = NULL_TREE;
1654 /* See if there's anything we need to do. */
1655 tmpl = DECL_TI_TEMPLATE (decl);
1656 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1657 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1658 if (TREE_PURPOSE (t))
1663 old_type = TREE_TYPE (decl);
1664 spec_types = TYPE_ARG_TYPES (old_type);
1666 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1668 /* Remove the this pointer, but remember the object's type for
1670 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1671 spec_types = TREE_CHAIN (spec_types);
1672 tmpl_types = TREE_CHAIN (tmpl_types);
1674 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1676 /* DECL may contain more parameters than TMPL due to the extra
1677 in-charge parameter in constructors and destructors. */
1678 in_charge = spec_types;
1679 spec_types = TREE_CHAIN (spec_types);
1681 if (DECL_HAS_VTT_PARM_P (decl))
1684 spec_types = TREE_CHAIN (spec_types);
1688 /* Compute the merged default arguments. */
1690 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1692 /* Compute the new FUNCTION_TYPE. */
1696 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1701 /* Put the in-charge parameter back. */
1702 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1703 TREE_VALUE (in_charge),
1706 new_type = build_method_type_directly (object_type,
1707 TREE_TYPE (old_type),
1711 new_type = build_function_type (TREE_TYPE (old_type),
1713 new_type = cp_build_type_attribute_variant (new_type,
1714 TYPE_ATTRIBUTES (old_type));
1715 new_type = build_exception_variant (new_type,
1716 TYPE_RAISES_EXCEPTIONS (old_type));
1717 TREE_TYPE (decl) = new_type;
1720 /* Check to see if the function just declared, as indicated in
1721 DECLARATOR, and in DECL, is a specialization of a function
1722 template. We may also discover that the declaration is an explicit
1723 instantiation at this point.
1725 Returns DECL, or an equivalent declaration that should be used
1726 instead if all goes well. Issues an error message if something is
1727 amiss. Returns error_mark_node if the error is not easily
1730 FLAGS is a bitmask consisting of the following flags:
1732 2: The function has a definition.
1733 4: The function is a friend.
1735 The TEMPLATE_COUNT is the number of references to qualifying
1736 template classes that appeared in the name of the function. For
1739 template <class T> struct S { void f(); };
1742 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1743 classes are not counted in the TEMPLATE_COUNT, so that in
1745 template <class T> struct S {};
1746 template <> struct S<int> { void f(); }
1747 template <> void S<int>::f();
1749 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1750 invalid; there should be no template <>.)
1752 If the function is a specialization, it is marked as such via
1753 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1754 is set up correctly, and it is added to the list of specializations
1755 for that template. */
1758 check_explicit_specialization (tree declarator,
1763 int have_def = flags & 2;
1764 int is_friend = flags & 4;
1765 int specialization = 0;
1766 int explicit_instantiation = 0;
1767 int member_specialization = 0;
1768 tree ctype = DECL_CLASS_CONTEXT (decl);
1769 tree dname = DECL_NAME (decl);
1774 if (!processing_specialization)
1777 tsk = tsk_excessive_parms;
1780 tsk = current_tmpl_spec_kind (template_count);
1785 if (processing_specialization)
1788 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1790 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1793 /* This could be something like:
1795 template <class T> void f(T);
1796 class S { friend void f<>(int); } */
1800 /* This case handles bogus declarations like template <>
1801 template <class T> void f<int>(); */
1803 error ("template-id %qD in declaration of primary template",
1810 case tsk_invalid_member_spec:
1811 /* The error has already been reported in
1812 check_specialization_scope. */
1813 return error_mark_node;
1815 case tsk_invalid_expl_inst:
1816 error ("template parameter list used in explicit instantiation");
1822 error ("definition provided for explicit instantiation");
1824 explicit_instantiation = 1;
1827 case tsk_excessive_parms:
1828 case tsk_insufficient_parms:
1829 if (tsk == tsk_excessive_parms)
1830 error ("too many template parameter lists in declaration of %qD",
1832 else if (template_header_count)
1833 error("too few template parameter lists in declaration of %qD", decl);
1835 error("explicit specialization of %qD must be introduced by "
1836 "%<template <>%>", decl);
1840 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1842 member_specialization = 1;
1848 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1850 /* This case handles bogus declarations like template <>
1851 template <class T> void f<int>(); */
1853 if (uses_template_parms (declarator))
1854 error ("function template partial specialization %qD "
1855 "is not allowed", declarator);
1857 error ("template-id %qD in declaration of primary template",
1862 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1863 /* This is a specialization of a member template, without
1864 specialization the containing class. Something like:
1866 template <class T> struct S {
1867 template <class U> void f (U);
1869 template <> template <class U> void S<int>::f(U) {}
1871 That's a specialization -- but of the entire template. */
1879 if (specialization || member_specialization)
1881 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1882 for (; t; t = TREE_CHAIN (t))
1883 if (TREE_PURPOSE (t))
1886 ("default argument specified in explicit specialization");
1891 if (specialization || member_specialization || explicit_instantiation)
1893 tree tmpl = NULL_TREE;
1894 tree targs = NULL_TREE;
1896 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1897 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1901 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1906 /* If there is no class context, the explicit instantiation
1907 must be at namespace scope. */
1908 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1910 /* Find the namespace binding, using the declaration
1912 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
1914 if (!fns || !is_overloaded_fn (fns))
1916 error ("%qD is not a template function", dname);
1917 fns = error_mark_node;
1921 tree fn = OVL_CURRENT (fns);
1922 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
1923 CP_DECL_CONTEXT (fn)))
1924 error ("%qD is not declared in %qD",
1925 decl, current_namespace);
1929 declarator = lookup_template_function (fns, NULL_TREE);
1932 if (declarator == error_mark_node)
1933 return error_mark_node;
1935 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1937 if (!explicit_instantiation)
1938 /* A specialization in class scope. This is invalid,
1939 but the error will already have been flagged by
1940 check_specialization_scope. */
1941 return error_mark_node;
1944 /* It's not valid to write an explicit instantiation in
1947 class C { template void f(); }
1949 This case is caught by the parser. However, on
1952 template class C { void f(); };
1954 (which is invalid) we can get here. The error will be
1961 else if (ctype != NULL_TREE
1962 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1965 /* Find the list of functions in ctype that have the same
1966 name as the declared function. */
1967 tree name = TREE_OPERAND (declarator, 0);
1968 tree fns = NULL_TREE;
1971 if (constructor_name_p (name, ctype))
1973 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1975 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1976 : !CLASSTYPE_DESTRUCTORS (ctype))
1978 /* From [temp.expl.spec]:
1980 If such an explicit specialization for the member
1981 of a class template names an implicitly-declared
1982 special member function (clause _special_), the
1983 program is ill-formed.
1985 Similar language is found in [temp.explicit]. */
1986 error ("specialization of implicitly-declared special member function");
1987 return error_mark_node;
1990 name = is_constructor ? ctor_identifier : dtor_identifier;
1993 if (!DECL_CONV_FN_P (decl))
1995 idx = lookup_fnfields_1 (ctype, name);
1997 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2001 VEC(tree,gc) *methods;
2004 /* For a type-conversion operator, we cannot do a
2005 name-based lookup. We might be looking for `operator
2006 int' which will be a specialization of `operator T'.
2007 So, we find *all* the conversion operators, and then
2008 select from them. */
2011 methods = CLASSTYPE_METHOD_VEC (ctype);
2013 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2014 VEC_iterate (tree, methods, idx, ovl);
2017 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2018 /* There are no more conversion functions. */
2021 /* Glue all these conversion functions together
2022 with those we already have. */
2023 for (; ovl; ovl = OVL_NEXT (ovl))
2024 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2028 if (fns == NULL_TREE)
2030 error ("no member function %qD declared in %qT", name, ctype);
2031 return error_mark_node;
2034 TREE_OPERAND (declarator, 0) = fns;
2037 /* Figure out what exactly is being specialized at this point.
2038 Note that for an explicit instantiation, even one for a
2039 member function, we cannot tell apriori whether the
2040 instantiation is for a member template, or just a member
2041 function of a template class. Even if a member template is
2042 being instantiated, the member template arguments may be
2043 elided if they can be deduced from the rest of the
2045 tmpl = determine_specialization (declarator, decl,
2047 member_specialization,
2050 if (!tmpl || tmpl == error_mark_node)
2051 /* We couldn't figure out what this declaration was
2053 return error_mark_node;
2056 tree gen_tmpl = most_general_template (tmpl);
2058 if (explicit_instantiation)
2060 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2061 is done by do_decl_instantiation later. */
2063 int arg_depth = TMPL_ARGS_DEPTH (targs);
2064 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2066 if (arg_depth > parm_depth)
2068 /* If TMPL is not the most general template (for
2069 example, if TMPL is a friend template that is
2070 injected into namespace scope), then there will
2071 be too many levels of TARGS. Remove some of them
2076 new_targs = make_tree_vec (parm_depth);
2077 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2078 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2079 = TREE_VEC_ELT (targs, i);
2083 return instantiate_template (tmpl, targs, tf_error);
2086 /* If we thought that the DECL was a member function, but it
2087 turns out to be specializing a static member function,
2088 make DECL a static member function as well. */
2089 if (DECL_STATIC_FUNCTION_P (tmpl)
2090 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2091 revert_static_member_fn (decl);
2093 /* If this is a specialization of a member template of a
2094 template class. In we want to return the TEMPLATE_DECL,
2095 not the specialization of it. */
2096 if (tsk == tsk_template)
2098 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2099 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2102 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2103 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2104 = DECL_SOURCE_LOCATION (decl);
2105 /* We want to use the argument list specified in the
2106 definition, not in the original declaration. */
2107 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2108 = DECL_ARGUMENTS (decl);
2113 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2114 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2116 /* Inherit default function arguments from the template
2117 DECL is specializing. */
2118 copy_default_args_to_explicit_spec (decl);
2120 /* This specialization has the same protection as the
2121 template it specializes. */
2122 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2123 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2124 /* The specialization has the same visibility as the
2125 template it specializes. */
2126 if (DECL_VISIBILITY_SPECIFIED (gen_tmpl))
2128 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2129 DECL_VISIBILITY (decl) = DECL_VISIBILITY (gen_tmpl);
2131 /* If DECL is a friend declaration, declared using an
2132 unqualified name, the namespace associated with DECL may
2133 have been set incorrectly. For example, in:
2135 template <typename T> void f(T);
2137 struct S { friend void f<int>(int); }
2140 we will have set the DECL_CONTEXT for the friend
2141 declaration to N, rather than to the global namespace. */
2142 if (DECL_NAMESPACE_SCOPE_P (decl))
2143 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2145 if (is_friend && !have_def)
2146 /* This is not really a declaration of a specialization.
2147 It's just the name of an instantiation. But, it's not
2148 a request for an instantiation, either. */
2149 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2150 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2151 /* This is indeed a specialization. In case of constructors
2152 and destructors, we need in-charge and not-in-charge
2153 versions in V3 ABI. */
2154 clone_function_decl (decl, /*update_method_vec_p=*/0);
2156 /* Register this specialization so that we can find it
2158 decl = register_specialization (decl, gen_tmpl, targs, is_friend);
2165 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2166 parameters. These are represented in the same format used for
2167 DECL_TEMPLATE_PARMS. */
2170 comp_template_parms (tree parms1, tree parms2)
2175 if (parms1 == parms2)
2178 for (p1 = parms1, p2 = parms2;
2179 p1 != NULL_TREE && p2 != NULL_TREE;
2180 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2182 tree t1 = TREE_VALUE (p1);
2183 tree t2 = TREE_VALUE (p2);
2186 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2187 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2189 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2192 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2194 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2195 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2197 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2200 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2202 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2207 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2208 /* One set of parameters has more parameters lists than the
2215 /* Complain if DECL shadows a template parameter.
2217 [temp.local]: A template-parameter shall not be redeclared within its
2218 scope (including nested scopes). */
2221 check_template_shadow (tree decl)
2225 /* If we're not in a template, we can't possibly shadow a template
2227 if (!current_template_parms)
2230 /* Figure out what we're shadowing. */
2231 if (TREE_CODE (decl) == OVERLOAD)
2232 decl = OVL_CURRENT (decl);
2233 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2235 /* If there's no previous binding for this name, we're not shadowing
2236 anything, let alone a template parameter. */
2240 /* If we're not shadowing a template parameter, we're done. Note
2241 that OLDDECL might be an OVERLOAD (or perhaps even an
2242 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2244 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2247 /* We check for decl != olddecl to avoid bogus errors for using a
2248 name inside a class. We check TPFI to avoid duplicate errors for
2249 inline member templates. */
2251 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2254 error ("declaration of %q+#D", decl);
2255 error (" shadows template parm %q+#D", olddecl);
2258 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2259 ORIG_LEVEL, DECL, and TYPE. */
2262 build_template_parm_index (int index,
2268 tree t = make_node (TEMPLATE_PARM_INDEX);
2269 TEMPLATE_PARM_IDX (t) = index;
2270 TEMPLATE_PARM_LEVEL (t) = level;
2271 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2272 TEMPLATE_PARM_DECL (t) = decl;
2273 TREE_TYPE (t) = type;
2274 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2275 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2276 TREE_READONLY (t) = TREE_READONLY (decl);
2281 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2282 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2283 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2284 new one is created. */
2287 reduce_template_parm_level (tree index, tree type, int levels)
2289 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2290 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2291 != TEMPLATE_PARM_LEVEL (index) - levels))
2293 tree orig_decl = TEMPLATE_PARM_DECL (index);
2296 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2297 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2298 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2299 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2300 DECL_ARTIFICIAL (decl) = 1;
2301 SET_DECL_TEMPLATE_PARM_P (decl);
2303 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2304 TEMPLATE_PARM_LEVEL (index) - levels,
2305 TEMPLATE_PARM_ORIG_LEVEL (index),
2307 TEMPLATE_PARM_DESCENDANTS (index) = t;
2309 /* Template template parameters need this. */
2310 if (TREE_CODE (decl) != CONST_DECL)
2311 DECL_TEMPLATE_PARMS (decl)
2312 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2315 return TEMPLATE_PARM_DESCENDANTS (index);
2318 /* Process information from new template parameter NEXT and append it to the
2319 LIST being built. This new parameter is a non-type parameter iff
2320 IS_NON_TYPE is true. */
2323 process_template_parm (tree list, tree next, bool is_non_type)
2331 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2332 defval = TREE_PURPOSE (parm);
2336 tree p = TREE_VALUE (tree_last (list));
2338 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2339 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2341 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2349 parm = TREE_VALUE (parm);
2351 SET_DECL_TEMPLATE_PARM_P (parm);
2355 The top-level cv-qualifiers on the template-parameter are
2356 ignored when determining its type. */
2357 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2359 /* A template parameter is not modifiable. */
2360 TREE_CONSTANT (parm) = 1;
2361 TREE_INVARIANT (parm) = 1;
2362 TREE_READONLY (parm) = 1;
2363 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2364 TREE_TYPE (parm) = void_type_node;
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 (inner_args, 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);
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 expr_type = TREE_TYPE (expr);
3462 /* HACK: Due to double coercion, we can get a
3463 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3464 which is the tree that we built on the first call (see
3465 below when coercing to reference to object or to reference to
3466 function). We just strip everything and get to the arg.
3467 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3469 if (TREE_CODE (expr) == NOP_EXPR)
3471 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3473 /* ??? Maybe we could use convert_from_reference here, but we
3474 would need to relax its constraints because the NOP_EXPR
3475 could actually change the type to something more cv-qualified,
3476 and this is not folded by convert_from_reference. */
3477 tree addr = TREE_OPERAND (expr, 0);
3478 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3479 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3480 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3481 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3482 (TREE_TYPE (expr_type),
3483 TREE_TYPE (TREE_TYPE (addr))));
3485 expr = TREE_OPERAND (addr, 0);
3486 expr_type = TREE_TYPE (expr);
3489 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3490 parameter is a pointer to object, through decay and
3491 qualification conversion. Let's strip everything. */
3492 else if (TYPE_PTROBV_P (type))
3495 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3496 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3497 /* Skip the ADDR_EXPR only if it is part of the decay for
3498 an array. Otherwise, it is part of the original argument
3499 in the source code. */
3500 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3501 expr = TREE_OPERAND (expr, 0);
3502 expr_type = TREE_TYPE (expr);
3506 /* [temp.arg.nontype]/5, bullet 1
3508 For a non-type template-parameter of integral or enumeration type,
3509 integral promotions (_conv.prom_) and integral conversions
3510 (_conv.integral_) are applied. */
3511 if (INTEGRAL_TYPE_P (type))
3513 if (!INTEGRAL_TYPE_P (expr_type))
3514 return error_mark_node;
3516 expr = fold_decl_constant_value (expr);
3517 /* Notice that there are constant expressions like '4 % 0' which
3518 do not fold into integer constants. */
3519 if (TREE_CODE (expr) != INTEGER_CST)
3521 error ("%qE is not a valid template argument for type %qT "
3522 "because it is a non-constant expression", expr, type);
3526 /* At this point, an implicit conversion does what we want,
3527 because we already know that the expression is of integral
3529 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3530 if (expr == error_mark_node)
3531 return error_mark_node;
3533 /* Conversion was allowed: fold it to a bare integer constant. */
3536 /* [temp.arg.nontype]/5, bullet 2
3538 For a non-type template-parameter of type pointer to object,
3539 qualification conversions (_conv.qual_) and the array-to-pointer
3540 conversion (_conv.array_) are applied. */
3541 else if (TYPE_PTROBV_P (type))
3543 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3545 A template-argument for a non-type, non-template template-parameter
3546 shall be one of: [...]
3548 -- the name of a non-type template-parameter;
3549 -- the address of an object or function with external linkage, [...]
3550 expressed as "& id-expression" where the & is optional if the name
3551 refers to a function or array, or if the corresponding
3552 template-parameter is a reference.
3554 Here, we do not care about functions, as they are invalid anyway
3555 for a parameter of type pointer-to-object. */
3556 bool constant_address_p =
3557 (TREE_CODE (expr) == ADDR_EXPR
3558 || TREE_CODE (expr_type) == ARRAY_TYPE
3559 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3561 expr = decay_conversion (expr);
3562 if (expr == error_mark_node)
3563 return error_mark_node;
3565 expr = perform_qualification_conversions (type, expr);
3566 if (expr == error_mark_node)
3567 return error_mark_node;
3569 if (!constant_address_p)
3571 error ("%qE is not a valid template argument for type %qT "
3572 "because it is not a constant pointer", expr, type);
3576 /* [temp.arg.nontype]/5, bullet 3
3578 For a non-type template-parameter of type reference to object, no
3579 conversions apply. The type referred to by the reference may be more
3580 cv-qualified than the (otherwise identical) type of the
3581 template-argument. The template-parameter is bound directly to the
3582 template-argument, which must be an lvalue. */
3583 else if (TYPE_REF_OBJ_P (type))
3585 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3587 return error_mark_node;
3589 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3591 error ("%qE is not a valid template argument for type %qT "
3592 "because of conflicts in cv-qualification", expr, type);
3596 if (!real_lvalue_p (expr))
3598 error ("%qE is not a valid template argument for type %qT "
3599 "because it is not a lvalue", expr, type);
3603 /* [temp.arg.nontype]/1
3605 A template-argument for a non-type, non-template template-parameter
3606 shall be one of: [...]
3608 -- the address of an object or function with external linkage. */
3609 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3611 error ("%qE is not a valid template argument for type %qT "
3612 "because object %qD has not external linkage",
3617 expr = build_nop (type, build_address (expr));
3619 /* [temp.arg.nontype]/5, bullet 4
3621 For a non-type template-parameter of type pointer to function, only
3622 the function-to-pointer conversion (_conv.func_) is applied. If the
3623 template-argument represents a set of overloaded functions (or a
3624 pointer to such), the matching function is selected from the set
3626 else if (TYPE_PTRFN_P (type))
3628 /* If the argument is a template-id, we might not have enough
3629 context information to decay the pointer. */
3630 if (!type_unknown_p (expr_type))
3632 expr = decay_conversion (expr);
3633 if (expr == error_mark_node)
3634 return error_mark_node;
3637 expr = convert_nontype_argument_function (type, expr);
3638 if (!expr || expr == error_mark_node)
3641 /* [temp.arg.nontype]/5, bullet 5
3643 For a non-type template-parameter of type reference to function, no
3644 conversions apply. If the template-argument represents a set of
3645 overloaded functions, the matching function is selected from the set
3647 else if (TYPE_REFFN_P (type))
3649 if (TREE_CODE (expr) == ADDR_EXPR)
3651 error ("%qE is not a valid template argument for type %qT "
3652 "because it is a pointer", expr, type);
3653 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3657 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3658 if (!expr || expr == error_mark_node)
3661 expr = build_nop (type, build_address (expr));
3663 /* [temp.arg.nontype]/5, bullet 6
3665 For a non-type template-parameter of type pointer to member function,
3666 no conversions apply. If the template-argument represents a set of
3667 overloaded member functions, the matching member function is selected
3668 from the set (_over.over_). */
3669 else if (TYPE_PTRMEMFUNC_P (type))
3671 expr = instantiate_type (type, expr, tf_none);
3672 if (expr == error_mark_node)
3673 return error_mark_node;
3675 /* There is no way to disable standard conversions in
3676 resolve_address_of_overloaded_function (called by
3677 instantiate_type). It is possible that the call succeeded by
3678 converting &B::I to &D::I (where B is a base of D), so we need
3679 to reject this conversion here.
3681 Actually, even if there was a way to disable standard conversions,
3682 it would still be better to reject them here so that we can
3683 provide a superior diagnostic. */
3684 if (!same_type_p (TREE_TYPE (expr), type))
3686 /* Make sure we are just one standard conversion off. */
3687 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3688 error ("%qE is not a valid template argument for type %qT "
3689 "because it is of type %qT", expr, type,
3691 inform ("standard conversions are not allowed in this context");
3695 /* [temp.arg.nontype]/5, bullet 7
3697 For a non-type template-parameter of type pointer to data member,
3698 qualification conversions (_conv.qual_) are applied. */
3699 else if (TYPE_PTRMEM_P (type))
3701 expr = perform_qualification_conversions (type, expr);
3702 if (expr == error_mark_node)
3705 /* A template non-type parameter must be one of the above. */
3709 /* Sanity check: did we actually convert the argument to the
3711 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3716 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3717 template template parameters. Both PARM_PARMS and ARG_PARMS are
3718 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3721 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3722 the case, then extra parameters must have default arguments.
3724 Consider the example:
3725 template <class T, class Allocator = allocator> class vector;
3726 template<template <class U> class TT> class C;
3728 C<vector> is a valid instantiation. PARM_PARMS for the above code
3729 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3730 T and Allocator) and OUTER_ARGS contains the argument that is used to
3731 substitute the TT parameter. */
3734 coerce_template_template_parms (tree parm_parms,
3736 tsubst_flags_t complain,
3740 int nparms, nargs, i;
3743 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3744 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3746 nparms = TREE_VEC_LENGTH (parm_parms);
3747 nargs = TREE_VEC_LENGTH (arg_parms);
3749 /* The rule here is opposite of coerce_template_parms. */
3752 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3755 for (i = 0; i < nparms; ++i)
3757 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3758 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3760 if (arg == NULL_TREE || arg == error_mark_node
3761 || parm == NULL_TREE || parm == error_mark_node)
3764 if (TREE_CODE (arg) != TREE_CODE (parm))
3767 switch (TREE_CODE (parm))
3773 /* We encounter instantiations of templates like
3774 template <template <template <class> class> class TT>
3777 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3778 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3780 if (!coerce_template_template_parms
3781 (parmparm, argparm, complain, in_decl, outer_args))
3787 /* The tsubst call is used to handle cases such as
3789 template <int> class C {};
3790 template <class T, template <T> class TT> class D {};
3793 i.e. the parameter list of TT depends on earlier parameters. */
3794 if (!dependent_type_p (TREE_TYPE (arg))
3796 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3808 /* Convert the indicated template ARG as necessary to match the
3809 indicated template PARM. Returns the converted ARG, or
3810 error_mark_node if the conversion was unsuccessful. Error and
3811 warning messages are issued under control of COMPLAIN. This
3812 conversion is for the Ith parameter in the parameter list. ARGS is
3813 the full set of template arguments deduced so far. */
3816 convert_template_argument (tree parm,
3819 tsubst_flags_t complain,
3825 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3827 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3829 if (TREE_CODE (arg) == TREE_LIST
3830 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3832 /* The template argument was the name of some
3833 member function. That's usually
3834 invalid, but static members are OK. In any
3835 case, grab the underlying fields/functions
3836 and issue an error later if required. */
3837 arg = TREE_VALUE (arg);
3838 TREE_TYPE (arg) = unknown_type_node;
3841 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3842 requires_type = (TREE_CODE (parm) == TYPE_DECL
3843 || requires_tmpl_type);
3845 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3846 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3847 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3848 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3851 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3852 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3853 arg = TYPE_STUB_DECL (arg);
3855 is_type = TYPE_P (arg) || is_tmpl_type;
3857 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3858 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3860 pedwarn ("to refer to a type member of a template parameter, "
3861 "use %<typename %E%>", arg);
3863 arg = make_typename_type (TREE_OPERAND (arg, 0),
3864 TREE_OPERAND (arg, 1),
3866 complain & tf_error);
3869 if (is_type != requires_type)
3873 if (complain & tf_error)
3875 error ("type/value mismatch at argument %d in template "
3876 "parameter list for %qD",
3879 error (" expected a constant of type %qT, got %qT",
3881 (is_tmpl_type ? DECL_NAME (arg) : arg));
3882 else if (requires_tmpl_type)
3883 error (" expected a class template, got %qE", arg);
3885 error (" expected a type, got %qE", arg);
3888 return error_mark_node;
3890 if (is_tmpl_type ^ requires_tmpl_type)
3892 if (in_decl && (complain & tf_error))
3894 error ("type/value mismatch at argument %d in template "
3895 "parameter list for %qD",
3898 error (" expected a type, got %qT", DECL_NAME (arg));
3900 error (" expected a class template, got %qT", arg);
3902 return error_mark_node;
3907 if (requires_tmpl_type)
3909 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3910 /* The number of argument required is not known yet.
3911 Just accept it for now. */
3912 val = TREE_TYPE (arg);
3915 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3916 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3918 if (coerce_template_template_parms (parmparm, argparm,
3924 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3926 if (val != error_mark_node
3927 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3928 val = TREE_TYPE (val);
3932 if (in_decl && (complain & tf_error))
3934 error ("type/value mismatch at argument %d in "
3935 "template parameter list for %qD",
3937 error (" expected a template of type %qD, got %qD",
3941 val = error_mark_node;
3947 /* We only form one instance of each template specialization.
3948 Therefore, if we use a non-canonical variant (i.e., a
3949 typedef), any future messages referring to the type will use
3950 the typedef, which is confusing if those future uses do not
3951 themselves also use the typedef. */
3953 val = canonical_type_variant (val);
3957 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3959 if (invalid_nontype_parm_type_p (t, complain))
3960 return error_mark_node;
3962 if (!uses_template_parms (arg) && !uses_template_parms (t))
3963 /* We used to call digest_init here. However, digest_init
3964 will report errors, which we don't want when complain
3965 is zero. More importantly, digest_init will try too
3966 hard to convert things: for example, `0' should not be
3967 converted to pointer type at this point according to
3968 the standard. Accepting this is not merely an
3969 extension, since deciding whether or not these
3970 conversions can occur is part of determining which
3971 function template to call, or whether a given explicit
3972 argument specification is valid. */
3973 val = convert_nontype_argument (t, arg);
3977 if (val == NULL_TREE)
3978 val = error_mark_node;
3979 else if (val == error_mark_node && (complain & tf_error))
3980 error ("could not convert template argument %qE to %qT", arg, t);
3986 /* Convert all template arguments to their appropriate types, and
3987 return a vector containing the innermost resulting template
3988 arguments. If any error occurs, return error_mark_node. Error and
3989 warning messages are issued under control of COMPLAIN.
3991 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3992 provided in ARGLIST, or else trailing parameters must have default
3993 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3994 deduction for any unspecified trailing arguments. */
3997 coerce_template_parms (tree parms,
4000 tsubst_flags_t complain,
4001 int require_all_arguments)
4003 int nparms, nargs, i, lost = 0;
4006 tree new_inner_args;
4008 inner_args = INNERMOST_TEMPLATE_ARGS (args);
4009 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
4010 nparms = TREE_VEC_LENGTH (parms);
4014 && require_all_arguments
4015 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
4017 if (complain & tf_error)
4019 error ("wrong number of template arguments (%d, should be %d)",
4023 error ("provided for %q+D", in_decl);
4026 return error_mark_node;
4029 new_inner_args = make_tree_vec (nparms);
4030 new_args = add_outermost_template_args (args, new_inner_args);
4031 for (i = 0; i < nparms; i++)
4036 /* Get the Ith template parameter. */
4037 parm = TREE_VEC_ELT (parms, i);
4039 /* Calculate the Ith argument. */
4041 arg = TREE_VEC_ELT (inner_args, i);
4042 else if (require_all_arguments)
4043 /* There must be a default arg in this case. */
4044 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4050 if (arg == error_mark_node)
4052 if (complain & tf_error)
4053 error ("template argument %d is invalid", i + 1);
4056 arg = convert_template_argument (TREE_VALUE (parm),
4057 arg, new_args, complain, i,
4060 if (arg == error_mark_node)
4062 TREE_VEC_ELT (new_inner_args, i) = arg;
4066 return error_mark_node;
4068 return new_inner_args;
4071 /* Returns 1 if template args OT and NT are equivalent. */
4074 template_args_equal (tree ot, tree nt)
4079 if (TREE_CODE (nt) == TREE_VEC)
4080 /* For member templates */
4081 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4082 else if (TYPE_P (nt))
4083 return TYPE_P (ot) && same_type_p (ot, nt);
4084 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4087 return cp_tree_equal (ot, nt);
4090 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4091 of template arguments. Returns 0 otherwise. */
4094 comp_template_args (tree oldargs, tree newargs)
4098 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4101 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4103 tree nt = TREE_VEC_ELT (newargs, i);
4104 tree ot = TREE_VEC_ELT (oldargs, i);
4106 if (! template_args_equal (ot, nt))
4112 /* Given class template name and parameter list, produce a user-friendly name
4113 for the instantiation. */
4116 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4118 static struct obstack scratch_obstack;
4119 static char *scratch_firstobj;
4122 if (!scratch_firstobj)
4123 gcc_obstack_init (&scratch_obstack);
4125 obstack_free (&scratch_obstack, scratch_firstobj);
4126 scratch_firstobj = (char *) obstack_alloc (&scratch_obstack, 1);
4128 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4129 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4133 nparms = TREE_VEC_LENGTH (parms);
4134 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4135 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4136 for (i = 0; i < nparms; i++)
4138 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4139 tree arg = TREE_VEC_ELT (arglist, i);
4144 if (TREE_CODE (parm) == TYPE_DECL)
4146 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4149 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4151 if (TREE_CODE (arg) == TEMPLATE_DECL)
4153 /* Already substituted with real template. Just output
4154 the template name here */
4155 tree context = DECL_CONTEXT (arg);
4158 /* The template may be defined in a namespace, or
4159 may be a member template. */
4160 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4161 || CLASS_TYPE_P (context));
4162 cat (decl_as_string (DECL_CONTEXT (arg),
4163 TFF_PLAIN_IDENTIFIER));
4166 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4169 /* Output the parameter declaration. */
4170 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4174 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4176 /* No need to check arglist against parmlist here; we did that
4177 in coerce_template_parms, called from lookup_template_class. */
4178 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4181 char *bufp = obstack_next_free (&scratch_obstack);
4183 while (bufp[offset - 1] == ' ')
4185 obstack_blank_fast (&scratch_obstack, offset);
4187 /* B<C<char> >, not B<C<char>> */
4188 if (bufp[offset - 1] == '>')
4193 return (char *) obstack_base (&scratch_obstack);
4197 classtype_mangled_name (tree t)
4199 if (CLASSTYPE_TEMPLATE_INFO (t)
4200 /* Specializations have already had their names set up in
4201 lookup_template_class. */
4202 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4204 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4206 /* For non-primary templates, the template parameters are
4207 implicit from their surrounding context. */
4208 if (PRIMARY_TEMPLATE_P (tmpl))
4210 tree name = DECL_NAME (tmpl);
4211 char *mangled_name = mangle_class_name_for_template
4212 (IDENTIFIER_POINTER (name),
4213 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4214 CLASSTYPE_TI_ARGS (t));
4215 tree id = get_identifier (mangled_name);
4216 IDENTIFIER_TEMPLATE (id) = name;
4221 return TYPE_IDENTIFIER (t);
4225 add_pending_template (tree d)
4227 tree ti = (TYPE_P (d)
4228 ? CLASSTYPE_TEMPLATE_INFO (d)
4229 : DECL_TEMPLATE_INFO (d));
4233 if (TI_PENDING_TEMPLATE_FLAG (ti))
4236 /* We are called both from instantiate_decl, where we've already had a
4237 tinst_level pushed, and instantiate_template, where we haven't.
4239 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4242 push_tinst_level (d);
4244 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4245 if (last_pending_template)
4246 TREE_CHAIN (last_pending_template) = pt;
4248 pending_templates = pt;
4250 last_pending_template = pt;
4252 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4259 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4260 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4261 documentation for TEMPLATE_ID_EXPR. */
4264 lookup_template_function (tree fns, tree arglist)
4268 if (fns == error_mark_node || arglist == error_mark_node)
4269 return error_mark_node;
4271 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4272 gcc_assert (fns && (is_overloaded_fn (fns)
4273 || TREE_CODE (fns) == IDENTIFIER_NODE));
4275 if (BASELINK_P (fns))
4277 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4279 BASELINK_FUNCTIONS (fns),
4284 type = TREE_TYPE (fns);
4285 if (TREE_CODE (fns) == OVERLOAD || !type)
4286 type = unknown_type_node;
4288 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4291 /* Within the scope of a template class S<T>, the name S gets bound
4292 (in build_self_reference) to a TYPE_DECL for the class, not a
4293 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4294 or one of its enclosing classes, and that type is a template,
4295 return the associated TEMPLATE_DECL. Otherwise, the original
4296 DECL is returned. */
4299 maybe_get_template_decl_from_type_decl (tree decl)
4301 return (decl != NULL_TREE
4302 && TREE_CODE (decl) == TYPE_DECL
4303 && DECL_ARTIFICIAL (decl)
4304 && CLASS_TYPE_P (TREE_TYPE (decl))
4305 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4306 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4309 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4310 parameters, find the desired type.
4312 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4314 IN_DECL, if non-NULL, is the template declaration we are trying to
4317 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4318 the class we are looking up.
4320 Issue error and warning messages under control of COMPLAIN.
4322 If the template class is really a local class in a template
4323 function, then the FUNCTION_CONTEXT is the function in which it is
4326 ??? Note that this function is currently called *twice* for each
4327 template-id: the first time from the parser, while creating the
4328 incomplete type (finish_template_type), and the second type during the
4329 real instantiation (instantiate_template_class). This is surely something
4330 that we want to avoid. It also causes some problems with argument
4331 coercion (see convert_nontype_argument for more information on this). */
4334 lookup_template_class (tree d1,
4339 tsubst_flags_t complain)
4341 tree template = NULL_TREE, parmlist;
4344 timevar_push (TV_NAME_LOOKUP);
4346 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4348 tree value = innermost_non_namespace_value (d1);
4349 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4354 push_decl_namespace (context);
4355 template = lookup_name (d1);
4356 template = maybe_get_template_decl_from_type_decl (template);
4358 pop_decl_namespace ();
4361 context = DECL_CONTEXT (template);
4363 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4365 tree type = TREE_TYPE (d1);
4367 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4368 an implicit typename for the second A. Deal with it. */
4369 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4370 type = TREE_TYPE (type);
4372 if (CLASSTYPE_TEMPLATE_INFO (type))
4374 template = CLASSTYPE_TI_TEMPLATE (type);
4375 d1 = DECL_NAME (template);
4378 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4379 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4381 template = TYPE_TI_TEMPLATE (d1);
4382 d1 = DECL_NAME (template);
4384 else if (TREE_CODE (d1) == TEMPLATE_DECL
4385 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4388 d1 = DECL_NAME (template);
4389 context = DECL_CONTEXT (template);
4392 /* Issue an error message if we didn't find a template. */
4395 if (complain & tf_error)
4396 error ("%qT is not a template", d1);
4397 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4400 if (TREE_CODE (template) != TEMPLATE_DECL
4401 /* Make sure it's a user visible template, if it was named by
4403 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4404 && !PRIMARY_TEMPLATE_P (template)))
4406 if (complain & tf_error)
4408 error ("non-template type %qT used as a template", d1);
4410 error ("for template declaration %q+D", in_decl);
4412 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4415 complain &= ~tf_user;
4417 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4419 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4420 template arguments */
4425 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4427 /* Consider an example where a template template parameter declared as
4429 template <class T, class U = std::allocator<T> > class TT
4431 The template parameter level of T and U are one level larger than
4432 of TT. To proper process the default argument of U, say when an
4433 instantiation `TT<int>' is seen, we need to build the full
4434 arguments containing {int} as the innermost level. Outer levels,
4435 available when not appearing as default template argument, can be
4436 obtained from `current_template_args ()'.
4438 Suppose that TT is later substituted with std::vector. The above
4439 instantiation is `TT<int, std::allocator<T> >' with TT at
4440 level 1, and T at level 2, while the template arguments at level 1
4441 becomes {std::vector} and the inner level 2 is {int}. */
4443 if (current_template_parms)
4444 arglist = add_to_template_args (current_template_args (), arglist);
4446 arglist2 = coerce_template_parms (parmlist, arglist, template,
4447 complain, /*require_all_args=*/1);
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),
4516 complain, /*require_all_args=*/1);
4518 /* Don't process further if one of the levels fails. */
4519 if (a == error_mark_node)
4521 /* Restore the ARGLIST to its full size. */
4522 TREE_VEC_LENGTH (arglist) = saved_depth;
4523 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4526 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4528 /* We temporarily reduce the length of the ARGLIST so
4529 that coerce_template_parms will see only the arguments
4530 corresponding to the template parameters it is
4532 TREE_VEC_LENGTH (arglist)--;
4535 /* Restore the ARGLIST to its full size. */
4536 TREE_VEC_LENGTH (arglist) = saved_depth;
4538 arglist = bound_args;
4542 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4543 INNERMOST_TEMPLATE_ARGS (arglist),
4545 complain, /*require_all_args=*/1);
4547 if (arglist == error_mark_node)
4548 /* We were unable to bind the arguments. */
4549 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4551 /* In the scope of a template class, explicit references to the
4552 template class refer to the type of the template, not any
4553 instantiation of it. For example, in:
4555 template <class T> class C { void f(C<T>); }
4557 the `C<T>' is just the same as `C'. Outside of the
4558 class, however, such a reference is an instantiation. */
4559 if (comp_template_args (TYPE_TI_ARGS (template_type),
4562 found = template_type;
4564 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4568 for (ctx = current_class_type;
4569 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4571 ? TYPE_CONTEXT (ctx)
4572 : DECL_CONTEXT (ctx)))
4573 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4576 /* We're not in the scope of the class, so the
4577 TEMPLATE_TYPE is not the type we want after all. */
4583 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4585 /* If we already have this specialization, return it. */
4586 found = retrieve_specialization (template, arglist,
4587 /*class_specializations_p=*/false);
4589 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4591 /* This type is a "partial instantiation" if any of the template
4592 arguments still involve template parameters. Note that we set
4593 IS_PARTIAL_INSTANTIATION for partial specializations as
4595 is_partial_instantiation = uses_template_parms (arglist);
4597 /* If the deduced arguments are invalid, then the binding
4599 if (!is_partial_instantiation
4600 && check_instantiated_args (template,
4601 INNERMOST_TEMPLATE_ARGS (arglist),
4603 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4605 if (!is_partial_instantiation
4606 && !PRIMARY_TEMPLATE_P (template)
4607 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4609 found = xref_tag_from_type (TREE_TYPE (template),
4610 DECL_NAME (template),
4611 /*tag_scope=*/ts_global);
4612 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4615 context = tsubst (DECL_CONTEXT (template), arglist,
4618 context = global_namespace;
4620 /* Create the type. */
4621 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4623 if (!is_partial_instantiation)
4625 set_current_access_from_decl (TYPE_NAME (template_type));
4626 t = start_enum (TYPE_IDENTIFIER (template_type));
4629 /* We don't want to call start_enum for this type, since
4630 the values for the enumeration constants may involve
4631 template parameters. And, no one should be interested
4632 in the enumeration constants for such a type. */
4633 t = make_node (ENUMERAL_TYPE);
4637 t = make_aggr_type (TREE_CODE (template_type));
4638 CLASSTYPE_DECLARED_CLASS (t)
4639 = CLASSTYPE_DECLARED_CLASS (template_type);
4640 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4641 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4643 /* A local class. Make sure the decl gets registered properly. */
4644 if (context == current_function_decl)
4645 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
4648 /* If we called start_enum or pushtag above, this information
4649 will already be set up. */
4652 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4654 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4655 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4656 TYPE_STUB_DECL (t) = type_decl;
4657 DECL_SOURCE_LOCATION (type_decl)
4658 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4661 type_decl = TYPE_NAME (t);
4663 TREE_PRIVATE (type_decl)
4664 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4665 TREE_PROTECTED (type_decl)
4666 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4667 DECL_IN_SYSTEM_HEADER (type_decl)
4668 = DECL_IN_SYSTEM_HEADER (template);
4669 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
4671 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
4672 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
4675 /* Set up the template information. We have to figure out which
4676 template is the immediate parent if this is a full
4678 if (parm_depth == 1 || is_partial_instantiation
4679 || !PRIMARY_TEMPLATE_P (template))
4680 /* This case is easy; there are no member templates involved. */
4684 /* This is a full instantiation of a member template. Look
4685 for a partial instantiation of which this is an instance. */
4687 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4688 found; found = TREE_CHAIN (found))
4691 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4693 /* We only want partial instantiations, here, not
4694 specializations or full instantiations. */
4695 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4696 || !uses_template_parms (TREE_VALUE (found)))
4699 /* Temporarily reduce by one the number of levels in the
4700 ARGLIST and in FOUND so as to avoid comparing the
4701 last set of arguments. */
4702 TREE_VEC_LENGTH (arglist)--;
4703 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4705 /* See if the arguments match. If they do, then TMPL is
4706 the partial instantiation we want. */
4707 success = comp_template_args (TREE_PURPOSE (found), arglist);
4709 /* Restore the argument vectors to their full size. */
4710 TREE_VEC_LENGTH (arglist)++;
4711 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4722 /* There was no partial instantiation. This happens
4723 where C<T> is a member template of A<T> and it's used
4726 template <typename T> struct B { A<T>::C<int> m; };
4729 Create the partial instantiation.
4731 TREE_VEC_LENGTH (arglist)--;
4732 found = tsubst (template, arglist, complain, NULL_TREE);
4733 TREE_VEC_LENGTH (arglist)++;
4737 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4738 DECL_TEMPLATE_INSTANTIATIONS (template)
4739 = tree_cons (arglist, t,
4740 DECL_TEMPLATE_INSTANTIATIONS (template));
4742 if (TREE_CODE (t) == ENUMERAL_TYPE
4743 && !is_partial_instantiation)
4744 /* Now that the type has been registered on the instantiations
4745 list, we set up the enumerators. Because the enumeration
4746 constants may involve the enumeration type itself, we make
4747 sure to register the type first, and then create the
4748 constants. That way, doing tsubst_expr for the enumeration
4749 constants won't result in recursive calls here; we'll find
4750 the instantiation and exit above. */
4751 tsubst_enum (template_type, t, arglist);
4753 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4755 if (TREE_CODE (t) != ENUMERAL_TYPE)
4756 DECL_NAME (type_decl) = classtype_mangled_name (t);
4757 if (is_partial_instantiation)
4758 /* If the type makes use of template parameters, the
4759 code that generates debugging information will crash. */
4760 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4762 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4764 timevar_pop (TV_NAME_LOOKUP);
4771 struct pointer_set_t *visited;
4774 /* Called from for_each_template_parm via walk_tree. */
4777 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4780 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4781 tree_fn_t fn = pfd->fn;
4782 void *data = pfd->data;
4785 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4786 return error_mark_node;
4788 switch (TREE_CODE (t))
4791 if (TYPE_PTRMEMFUNC_P (t))
4797 if (!TYPE_TEMPLATE_INFO (t))
4799 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4800 fn, data, pfd->visited))
4801 return error_mark_node;
4805 /* Since we're not going to walk subtrees, we have to do this
4807 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4809 return error_mark_node;
4813 /* Check the return type. */
4814 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4815 return error_mark_node;
4817 /* Check the parameter types. Since default arguments are not
4818 instantiated until they are needed, the TYPE_ARG_TYPES may
4819 contain expressions that involve template parameters. But,
4820 no-one should be looking at them yet. And, once they're
4821 instantiated, they don't contain template parameters, so
4822 there's no point in looking at them then, either. */
4826 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4827 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4829 return error_mark_node;
4831 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4832 want walk_tree walking into them itself. */
4838 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4840 return error_mark_node;
4845 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4846 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4848 return error_mark_node;
4853 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4854 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4856 return error_mark_node;
4857 if (DECL_CONTEXT (t)
4858 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4860 return error_mark_node;
4863 case BOUND_TEMPLATE_TEMPLATE_PARM:
4864 /* Record template parameters such as `T' inside `TT<T>'. */
4865 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4866 return error_mark_node;
4869 case TEMPLATE_TEMPLATE_PARM:
4870 case TEMPLATE_TYPE_PARM:
4871 case TEMPLATE_PARM_INDEX:
4872 if (fn && (*fn)(t, data))
4873 return error_mark_node;
4875 return error_mark_node;
4879 /* A template template parameter is encountered. */
4880 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4881 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4882 return error_mark_node;
4884 /* Already substituted template template parameter */
4890 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4891 data, pfd->visited))
4892 return error_mark_node;
4896 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4897 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4898 (TREE_TYPE (t)), fn, data,
4900 return error_mark_node;
4905 /* If there's no type, then this thing must be some expression
4906 involving template parameters. */
4907 if (!fn && !TREE_TYPE (t))
4908 return error_mark_node;
4913 case REINTERPRET_CAST_EXPR:
4914 case CONST_CAST_EXPR:
4915 case STATIC_CAST_EXPR:
4916 case DYNAMIC_CAST_EXPR:
4920 case PSEUDO_DTOR_EXPR:
4922 return error_mark_node;
4926 /* If we do not handle this case specially, we end up walking
4927 the BINFO hierarchy, which is circular, and therefore
4928 confuses walk_tree. */
4930 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4932 return error_mark_node;
4939 /* We didn't find any template parameters we liked. */
4943 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4944 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4945 call FN with the parameter and the DATA.
4946 If FN returns nonzero, the iteration is terminated, and
4947 for_each_template_parm returns 1. Otherwise, the iteration
4948 continues. If FN never returns a nonzero value, the value
4949 returned by for_each_template_parm is 0. If FN is NULL, it is
4950 considered to be the function which always returns 1. */
4953 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4954 struct pointer_set_t *visited)
4956 struct pair_fn_data pfd;
4963 /* Walk the tree. (Conceptually, we would like to walk without
4964 duplicates, but for_each_template_parm_r recursively calls
4965 for_each_template_parm, so we would need to reorganize a fair
4966 bit to use walk_tree_without_duplicates, so we keep our own
4969 pfd.visited = visited;
4971 pfd.visited = pointer_set_create ();
4972 result = walk_tree (&t,
4973 for_each_template_parm_r,
4975 pfd.visited) != NULL_TREE;
4980 pointer_set_destroy (pfd.visited);
4987 /* Returns true if T depends on any template parameter. */
4990 uses_template_parms (tree t)
4993 int saved_processing_template_decl;
4995 saved_processing_template_decl = processing_template_decl;
4996 if (!saved_processing_template_decl)
4997 processing_template_decl = 1;
4999 dependent_p = dependent_type_p (t);
5000 else if (TREE_CODE (t) == TREE_VEC)
5001 dependent_p = any_dependent_template_arguments_p (t);
5002 else if (TREE_CODE (t) == TREE_LIST)
5003 dependent_p = (uses_template_parms (TREE_VALUE (t))
5004 || uses_template_parms (TREE_CHAIN (t)));
5005 else if (TREE_CODE (t) == TYPE_DECL)
5006 dependent_p = dependent_type_p (TREE_TYPE (t));
5009 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
5010 || TREE_CODE (t) == OVERLOAD
5011 || TREE_CODE (t) == BASELINK
5012 || TREE_CODE (t) == IDENTIFIER_NODE
5013 || CONSTANT_CLASS_P (t))
5014 dependent_p = (type_dependent_expression_p (t)
5015 || value_dependent_expression_p (t));
5018 gcc_assert (t == error_mark_node);
5019 dependent_p = false;
5022 processing_template_decl = saved_processing_template_decl;
5027 /* Returns true if T depends on any template parameter with level LEVEL. */
5030 uses_template_parms_level (tree t, int level)
5032 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
5035 static int tinst_depth;
5036 extern int max_tinst_depth;
5037 #ifdef GATHER_STATISTICS
5040 static int tinst_level_tick;
5041 static int last_template_error_tick;
5043 /* We're starting to instantiate D; record the template instantiation context
5044 for diagnostics and to restore it later. */
5047 push_tinst_level (tree d)
5051 if (tinst_depth >= max_tinst_depth)
5053 /* If the instantiation in question still has unbound template parms,
5054 we don't really care if we can't instantiate it, so just return.
5055 This happens with base instantiation for implicit `typename'. */
5056 if (uses_template_parms (d))
5059 last_template_error_tick = tinst_level_tick;
5060 error ("template instantiation depth exceeds maximum of %d (use "
5061 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5062 max_tinst_depth, d);
5064 print_instantiation_context ();
5069 new = make_node (TINST_LEVEL);
5070 TINST_DECL (new) = d;
5071 TINST_LOCATION (new) = input_location;
5072 TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
5073 TREE_CHAIN (new) = current_tinst_level;
5074 current_tinst_level = new;
5077 #ifdef GATHER_STATISTICS
5078 if (tinst_depth > depth_reached)
5079 depth_reached = tinst_depth;
5086 /* We're done instantiating this template; return to the instantiation
5090 pop_tinst_level (void)
5092 tree old = current_tinst_level;
5094 /* Restore the filename and line number stashed away when we started
5095 this instantiation. */
5096 input_location = TINST_LOCATION (old);
5097 in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
5098 current_tinst_level = TREE_CHAIN (old);
5103 /* We're instantiating a deferred template; restore the template
5104 instantiation context in which the instantiation was requested, which
5105 is one step out from LEVEL. */
5108 reopen_tinst_level (tree level)
5113 for (t = level; t; t = TREE_CHAIN (t))
5116 current_tinst_level = level;
5120 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5121 vector of template arguments, as for tsubst.
5123 Returns an appropriate tsubst'd friend declaration. */
5126 tsubst_friend_function (tree decl, tree args)
5130 if (TREE_CODE (decl) == FUNCTION_DECL
5131 && DECL_TEMPLATE_INSTANTIATION (decl)
5132 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5133 /* This was a friend declared with an explicit template
5134 argument list, e.g.:
5138 to indicate that f was a template instantiation, not a new
5139 function declaration. Now, we have to figure out what
5140 instantiation of what template. */
5142 tree template_id, arglist, fns;
5145 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5147 /* Friend functions are looked up in the containing namespace scope.
5148 We must enter that scope, to avoid finding member functions of the
5149 current cless with same name. */
5150 push_nested_namespace (ns);
5151 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5152 tf_error | tf_warning, NULL_TREE);
5153 pop_nested_namespace (ns);
5154 arglist = tsubst (DECL_TI_ARGS (decl), args,
5155 tf_error | tf_warning, NULL_TREE);
5156 template_id = lookup_template_function (fns, arglist);
5158 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5159 tmpl = determine_specialization (template_id, new_friend,
5161 /*need_member_template=*/0,
5162 TREE_VEC_LENGTH (args));
5163 return instantiate_template (tmpl, new_args, tf_error);
5166 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5168 /* The NEW_FRIEND will look like an instantiation, to the
5169 compiler, but is not an instantiation from the point of view of
5170 the language. For example, we might have had:
5172 template <class T> struct S {
5173 template <class U> friend void f(T, U);
5176 Then, in S<int>, template <class U> void f(int, U) is not an
5177 instantiation of anything. */
5178 if (new_friend == error_mark_node)
5179 return error_mark_node;
5181 DECL_USE_TEMPLATE (new_friend) = 0;
5182 if (TREE_CODE (decl) == TEMPLATE_DECL)
5184 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5185 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5186 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5189 /* The mangled name for the NEW_FRIEND is incorrect. The function
5190 is not a template instantiation and should not be mangled like
5191 one. Therefore, we forget the mangling here; we'll recompute it
5192 later if we need it. */
5193 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5195 SET_DECL_RTL (new_friend, NULL_RTX);
5196 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5199 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5202 tree new_friend_template_info;
5203 tree new_friend_result_template_info;
5205 int new_friend_is_defn;
5207 /* We must save some information from NEW_FRIEND before calling
5208 duplicate decls since that function will free NEW_FRIEND if
5210 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5211 new_friend_is_defn =
5212 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5213 (template_for_substitution (new_friend)))
5215 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5217 /* This declaration is a `primary' template. */
5218 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5220 new_friend_result_template_info
5221 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5224 new_friend_result_template_info = NULL_TREE;
5226 /* Inside pushdecl_namespace_level, we will push into the
5227 current namespace. However, the friend function should go
5228 into the namespace of the template. */
5229 ns = decl_namespace_context (new_friend);
5230 push_nested_namespace (ns);
5231 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
5232 pop_nested_namespace (ns);
5234 if (old_decl != new_friend)
5236 /* This new friend declaration matched an existing
5237 declaration. For example, given:
5239 template <class T> void f(T);
5240 template <class U> class C {
5241 template <class T> friend void f(T) {}
5244 the friend declaration actually provides the definition
5245 of `f', once C has been instantiated for some type. So,
5246 old_decl will be the out-of-class template declaration,
5247 while new_friend is the in-class definition.
5249 But, if `f' was called before this point, the
5250 instantiation of `f' will have DECL_TI_ARGS corresponding
5251 to `T' but not to `U', references to which might appear
5252 in the definition of `f'. Previously, the most general
5253 template for an instantiation of `f' was the out-of-class
5254 version; now it is the in-class version. Therefore, we
5255 run through all specialization of `f', adding to their
5256 DECL_TI_ARGS appropriately. In particular, they need a
5257 new set of outer arguments, corresponding to the
5258 arguments for this class instantiation.
5260 The same situation can arise with something like this:
5263 template <class T> class C {
5267 when `C<int>' is instantiated. Now, `f(int)' is defined
5270 if (!new_friend_is_defn)
5271 /* On the other hand, if the in-class declaration does
5272 *not* provide a definition, then we don't want to alter
5273 existing definitions. We can just leave everything
5278 /* Overwrite whatever template info was there before, if
5279 any, with the new template information pertaining to
5281 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5283 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5284 reregister_specialization (new_friend,
5285 most_general_template (old_decl),
5290 tree new_friend_args;
5292 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5293 = new_friend_result_template_info;
5295 new_friend_args = TI_ARGS (new_friend_template_info);
5296 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5300 tree spec = TREE_VALUE (t);
5303 = add_outermost_template_args (new_friend_args,
5304 DECL_TI_ARGS (spec));
5307 /* Now, since specializations are always supposed to
5308 hang off of the most general template, we must move
5310 t = most_general_template (old_decl);
5313 DECL_TEMPLATE_SPECIALIZATIONS (t)
5314 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5315 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5316 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5321 /* The information from NEW_FRIEND has been merged into OLD_DECL
5322 by duplicate_decls. */
5323 new_friend = old_decl;
5328 tree context = DECL_CONTEXT (new_friend);
5332 template <class T> class C {
5333 template <class U> friend void C1<U>::f (); // case 1
5334 friend void C2<T>::f (); // case 2
5336 we only need to make sure CONTEXT is a complete type for
5337 case 2. To distinguish between the two cases, we note that
5338 CONTEXT of case 1 remains dependent type after tsubst while
5339 this isn't true for case 2. */
5340 ++processing_template_decl;
5341 dependent_p = dependent_type_p (context);
5342 --processing_template_decl;
5345 && !complete_type_or_else (context, NULL_TREE))
5346 return error_mark_node;
5348 if (COMPLETE_TYPE_P (context))
5350 /* Check to see that the declaration is really present, and,
5351 possibly obtain an improved declaration. */
5352 tree fn = check_classfn (context,
5353 new_friend, NULL_TREE);
5363 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5364 template arguments, as for tsubst.
5366 Returns an appropriate tsubst'd friend type or error_mark_node on
5370 tsubst_friend_class (tree friend_tmpl, tree args)
5376 context = DECL_CONTEXT (friend_tmpl);
5380 if (TREE_CODE (context) == NAMESPACE_DECL)
5381 push_nested_namespace (context);
5383 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5386 /* First, we look for a class template. */
5387 tmpl = lookup_name (DECL_NAME (friend_tmpl));
5389 /* But, if we don't find one, it might be because we're in a
5390 situation like this:
5398 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5399 for `S<int>', not the TEMPLATE_DECL. */
5400 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5402 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
5403 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5406 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5408 /* The friend template has already been declared. Just
5409 check to see that the declarations match, and install any new
5410 default parameters. We must tsubst the default parameters,
5411 of course. We only need the innermost template parameters
5412 because that is all that redeclare_class_template will look
5414 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5415 > TMPL_ARGS_DEPTH (args))
5418 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5419 args, tf_error | tf_warning);
5420 redeclare_class_template (TREE_TYPE (tmpl), parms);
5423 friend_type = TREE_TYPE (tmpl);
5427 /* The friend template has not already been declared. In this
5428 case, the instantiation of the template class will cause the
5429 injection of this template into the global scope. */
5430 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5432 /* The new TMPL is not an instantiation of anything, so we
5433 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5434 the new type because that is supposed to be the corresponding
5435 template decl, i.e., TMPL. */
5436 DECL_USE_TEMPLATE (tmpl) = 0;
5437 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5438 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5439 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5440 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5442 /* Inject this template into the global scope. */
5443 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
5448 if (TREE_CODE (context) == NAMESPACE_DECL)
5449 pop_nested_namespace (context);
5451 pop_nested_class ();
5457 /* Returns zero if TYPE cannot be completed later due to circularity.
5458 Otherwise returns one. */
5461 can_complete_type_without_circularity (tree type)
5463 if (type == NULL_TREE || type == error_mark_node)
5465 else if (COMPLETE_TYPE_P (type))
5467 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5468 return can_complete_type_without_circularity (TREE_TYPE (type));
5469 else if (CLASS_TYPE_P (type)
5470 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5477 instantiate_class_template (tree type)
5479 tree template, args, pattern, t, member;
5484 if (type == error_mark_node)
5485 return error_mark_node;
5487 if (TYPE_BEING_DEFINED (type)
5488 || COMPLETE_TYPE_P (type)
5489 || dependent_type_p (type))
5492 /* Figure out which template is being instantiated. */
5493 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5494 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5496 /* Figure out which arguments are being used to do the
5498 args = CLASSTYPE_TI_ARGS (type);
5500 /* Determine what specialization of the original template to
5502 t = most_specialized_class (template, args);
5503 if (t == error_mark_node)
5505 const char *str = "candidates are:";
5506 error ("ambiguous class template instantiation for %q#T", type);
5507 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5510 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5512 error ("%s %+#T", str, TREE_TYPE (t));
5516 TYPE_BEING_DEFINED (type) = 1;
5517 return error_mark_node;
5521 pattern = TREE_TYPE (t);
5523 pattern = TREE_TYPE (template);
5525 /* If the template we're instantiating is incomplete, then clearly
5526 there's nothing we can do. */
5527 if (!COMPLETE_TYPE_P (pattern))
5530 /* If we've recursively instantiated too many templates, stop. */
5531 if (! push_tinst_level (type))
5534 /* Now we're really doing the instantiation. Mark the type as in
5535 the process of being defined. */
5536 TYPE_BEING_DEFINED (type) = 1;
5538 /* We may be in the middle of deferred access check. Disable
5540 push_deferring_access_checks (dk_no_deferred);
5542 push_to_top_level ();
5546 /* This TYPE is actually an instantiation of a partial
5547 specialization. We replace the innermost set of ARGS with
5548 the arguments appropriate for substitution. For example,
5551 template <class T> struct S {};
5552 template <class T> struct S<T*> {};
5554 and supposing that we are instantiating S<int*>, ARGS will
5555 present be {int*} but we need {int}. */
5557 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5560 /* If there were multiple levels in ARGS, replacing the
5561 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5562 want, so we make a copy first. */
5563 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5565 args = copy_node (args);
5566 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5572 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5574 /* Set the input location to the template definition. This is needed
5575 if tsubsting causes an error. */
5576 typedecl = TYPE_MAIN_DECL (type);
5577 input_location = DECL_SOURCE_LOCATION (typedecl);
5578 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
5580 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5581 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5582 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5583 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5584 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5585 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5586 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5587 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5588 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5589 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5590 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5591 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5592 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5593 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5594 if (ANON_AGGR_TYPE_P (pattern))
5595 SET_ANON_AGGR_TYPE_P (type);
5596 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
5598 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
5599 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
5602 pbinfo = TYPE_BINFO (pattern);
5604 /* We should never instantiate a nested class before its enclosing
5605 class; we need to look up the nested class by name before we can
5606 instantiate it, and that lookup should instantiate the enclosing
5608 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5609 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5610 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5612 base_list = NULL_TREE;
5613 if (BINFO_N_BASE_BINFOS (pbinfo))
5616 tree context = TYPE_CONTEXT (type);
5620 /* We must enter the scope containing the type, as that is where
5621 the accessibility of types named in dependent bases are
5623 pushed_scope = push_scope (context ? context : global_namespace);
5625 /* Substitute into each of the bases to determine the actual
5627 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5630 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5632 /* Substitute to figure out the base class. */
5633 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5634 if (base == error_mark_node)
5637 base_list = tree_cons (access, base, base_list);
5638 if (BINFO_VIRTUAL_P (pbase_binfo))
5639 TREE_TYPE (base_list) = integer_type_node;
5642 /* The list is now in reverse order; correct that. */
5643 base_list = nreverse (base_list);
5646 pop_scope (pushed_scope);
5648 /* Now call xref_basetypes to set up all the base-class
5650 xref_basetypes (type, base_list);
5653 /* Now that our base classes are set up, enter the scope of the
5654 class, so that name lookups into base classes, etc. will work
5655 correctly. This is precisely analogous to what we do in
5656 begin_class_definition when defining an ordinary non-template
5660 /* Now members are processed in the order of declaration. */
5661 for (member = CLASSTYPE_DECL_LIST (pattern);
5662 member; member = TREE_CHAIN (member))
5664 tree t = TREE_VALUE (member);
5666 if (TREE_PURPOSE (member))
5670 /* Build new CLASSTYPE_NESTED_UTDS. */
5673 bool class_template_p;
5675 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
5676 && TYPE_LANG_SPECIFIC (t)
5677 && CLASSTYPE_IS_TEMPLATE (t));
5678 /* If the member is a class template, then -- even after
5679 substitution -- there may be dependent types in the
5680 template argument list for the class. We increment
5681 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5682 that function will assume that no types are dependent
5683 when outside of a template. */
5684 if (class_template_p)
5685 ++processing_template_decl;
5686 newtag = tsubst (t, args, tf_error, NULL_TREE);
5687 if (class_template_p)
5688 --processing_template_decl;
5689 if (newtag == error_mark_node)
5692 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5694 tree name = TYPE_IDENTIFIER (t);
5696 if (class_template_p)
5697 /* Unfortunately, lookup_template_class sets
5698 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5699 instantiation (i.e., for the type of a member
5700 template class nested within a template class.)
5701 This behavior is required for
5702 maybe_process_partial_specialization to work
5703 correctly, but is not accurate in this case;
5704 the TAG is not an instantiation of anything.
5705 (The corresponding TEMPLATE_DECL is an
5706 instantiation, but the TYPE is not.) */
5707 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5709 /* Now, we call pushtag to put this NEWTAG into the scope of
5710 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5711 pushtag calling push_template_decl. We don't have to do
5712 this for enums because it will already have been done in
5715 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5716 pushtag (name, newtag, /*tag_scope=*/ts_current);
5719 else if (TREE_CODE (t) == FUNCTION_DECL
5720 || DECL_FUNCTION_TEMPLATE_P (t))
5722 /* Build new TYPE_METHODS. */
5725 if (TREE_CODE (t) == TEMPLATE_DECL)
5726 ++processing_template_decl;
5727 r = tsubst (t, args, tf_error, NULL_TREE);
5728 if (TREE_CODE (t) == TEMPLATE_DECL)
5729 --processing_template_decl;
5730 set_current_access_from_decl (r);
5731 grok_special_member_properties (r);
5732 finish_member_declaration (r);
5736 /* Build new TYPE_FIELDS. */
5738 if (TREE_CODE (t) != CONST_DECL)
5742 /* The the file and line for this declaration, to
5743 assist in error message reporting. Since we
5744 called push_tinst_level above, we don't need to
5746 input_location = DECL_SOURCE_LOCATION (t);
5748 if (TREE_CODE (t) == TEMPLATE_DECL)
5749 ++processing_template_decl;
5750 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5751 if (TREE_CODE (t) == TEMPLATE_DECL)
5752 --processing_template_decl;
5753 if (TREE_CODE (r) == VAR_DECL)
5757 [t]he initialization (and any associated
5758 side-effects) of a static data member does
5759 not occur unless the static data member is
5760 itself used in a way that requires the
5761 definition of the static data member to
5764 Therefore, we do not substitute into the
5765 initialized for the static data member here. */
5766 finish_static_data_member_decl
5769 /*asmspec_tree=*/NULL_TREE,
5771 if (DECL_INITIALIZED_IN_CLASS_P (r))
5772 check_static_variable_definition (r, TREE_TYPE (r));
5774 else if (TREE_CODE (r) == FIELD_DECL)
5776 /* Determine whether R has a valid type and can be
5777 completed later. If R is invalid, then it is
5778 replaced by error_mark_node so that it will not be
5779 added to TYPE_FIELDS. */
5780 tree rtype = TREE_TYPE (r);
5781 if (can_complete_type_without_circularity (rtype))
5782 complete_type (rtype);
5784 if (!COMPLETE_TYPE_P (rtype))
5786 cxx_incomplete_type_error (r, rtype);
5787 r = error_mark_node;
5791 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5792 such a thing will already have been added to the field
5793 list by tsubst_enum in finish_member_declaration in the
5794 CLASSTYPE_NESTED_UTDS case above. */
5795 if (!(TREE_CODE (r) == TYPE_DECL
5796 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5797 && DECL_ARTIFICIAL (r)))
5799 set_current_access_from_decl (r);
5800 finish_member_declaration (r);
5807 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5809 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5811 tree friend_type = t;
5812 bool adjust_processing_template_decl = false;
5814 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5816 /* template <class T> friend class C; */
5817 friend_type = tsubst_friend_class (friend_type, args);
5818 adjust_processing_template_decl = true;
5820 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5822 /* template <class T> friend class C::D; */
5823 friend_type = tsubst (friend_type, args,
5824 tf_error | tf_warning, NULL_TREE);
5825 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5826 friend_type = TREE_TYPE (friend_type);
5827 adjust_processing_template_decl = true;
5829 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5831 /* This could be either
5835 when dependent_type_p is false or
5837 template <class U> friend class T::C;
5840 friend_type = tsubst (friend_type, args,
5841 tf_error | tf_warning, NULL_TREE);
5842 /* Bump processing_template_decl for correct
5843 dependent_type_p calculation. */
5844 ++processing_template_decl;
5845 if (dependent_type_p (friend_type))
5846 adjust_processing_template_decl = true;
5847 --processing_template_decl;
5849 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
5850 && hidden_name_p (TYPE_NAME (friend_type)))
5854 where C hasn't been declared yet. Let's lookup name
5855 from namespace scope directly, bypassing any name that
5856 come from dependent base class. */
5857 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5859 /* The call to xref_tag_from_type does injection for friend
5861 push_nested_namespace (ns);
5863 xref_tag_from_type (friend_type, NULL_TREE,
5864 /*tag_scope=*/ts_current);
5865 pop_nested_namespace (ns);
5867 else if (uses_template_parms (friend_type))
5868 /* friend class C<T>; */
5869 friend_type = tsubst (friend_type, args,
5870 tf_error | tf_warning, NULL_TREE);
5875 where C is already declared or
5877 friend class C<int>;
5879 We don't have to do anything in these cases. */
5881 if (adjust_processing_template_decl)
5882 /* Trick make_friend_class into realizing that the friend
5883 we're adding is a template, not an ordinary class. It's
5884 important that we use make_friend_class since it will
5885 perform some error-checking and output cross-reference
5887 ++processing_template_decl;
5889 if (friend_type != error_mark_node)
5890 make_friend_class (type, friend_type, /*complain=*/false);
5892 if (adjust_processing_template_decl)
5893 --processing_template_decl;
5897 /* Build new DECL_FRIENDLIST. */
5900 /* The the file and line for this declaration, to
5901 assist in error message reporting. Since we
5902 called push_tinst_level above, we don't need to
5904 input_location = DECL_SOURCE_LOCATION (t);
5906 if (TREE_CODE (t) == TEMPLATE_DECL)
5908 ++processing_template_decl;
5909 push_deferring_access_checks (dk_no_check);
5912 r = tsubst_friend_function (t, args);
5913 add_friend (type, r, /*complain=*/false);
5914 if (TREE_CODE (t) == TEMPLATE_DECL)
5916 pop_deferring_access_checks ();
5917 --processing_template_decl;
5923 /* Set the file and line number information to whatever is given for
5924 the class itself. This puts error messages involving generated
5925 implicit functions at a predictable point, and the same point
5926 that would be used for non-template classes. */
5927 input_location = DECL_SOURCE_LOCATION (typedecl);
5929 unreverse_member_declarations (type);
5930 finish_struct_1 (type);
5931 TYPE_BEING_DEFINED (type) = 0;
5933 /* Now that the class is complete, instantiate default arguments for
5934 any member functions. We don't do this earlier because the
5935 default arguments may reference members of the class. */
5936 if (!PRIMARY_TEMPLATE_P (template))
5937 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5938 if (TREE_CODE (t) == FUNCTION_DECL
5939 /* Implicitly generated member functions will not have template
5940 information; they are not instantiations, but instead are
5941 created "fresh" for each instantiation. */
5942 && DECL_TEMPLATE_INFO (t))
5943 tsubst_default_arguments (t);
5946 pop_from_top_level ();
5947 pop_deferring_access_checks ();
5950 /* The vtable for a template class can be emitted in any translation
5951 unit in which the class is instantiated. When there is no key
5952 method, however, finish_struct_1 will already have added TYPE to
5953 the keyed_classes list. */
5954 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5955 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5961 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5967 else if (TYPE_P (t))
5968 r = tsubst (t, args, complain, in_decl);
5971 r = tsubst_expr (t, args, complain, in_decl);
5972 r = fold_non_dependent_expr (r);
5977 /* Substitute ARGS into the vector or list of template arguments T. */
5980 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5982 int len = TREE_VEC_LENGTH (t);
5983 int need_new = 0, i;
5984 tree *elts = (tree *) alloca (len * sizeof (tree));
5986 for (i = 0; i < len; i++)
5988 tree orig_arg = TREE_VEC_ELT (t, i);
5991 if (TREE_CODE (orig_arg) == TREE_VEC)
5992 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5994 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5996 if (new_arg == error_mark_node)
5997 return error_mark_node;
6000 if (new_arg != orig_arg)
6007 t = make_tree_vec (len);
6008 for (i = 0; i < len; i++)
6009 TREE_VEC_ELT (t, i) = elts[i];
6014 /* Return the result of substituting ARGS into the template parameters
6015 given by PARMS. If there are m levels of ARGS and m + n levels of
6016 PARMS, then the result will contain n levels of PARMS. For
6017 example, if PARMS is `template <class T> template <class U>
6018 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
6019 result will be `template <int*, double, class V>'. */
6022 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
6027 /* When substituting into a template, we must set
6028 PROCESSING_TEMPLATE_DECL as the template parameters may be
6029 dependent if they are based on one-another, and the dependency
6030 predicates are short-circuit outside of templates. */
6031 ++processing_template_decl;
6033 for (new_parms = &r;
6034 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
6035 new_parms = &(TREE_CHAIN (*new_parms)),
6036 parms = TREE_CHAIN (parms))
6039 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
6042 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
6044 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
6045 tree default_value = TREE_PURPOSE (tuple);
6046 tree parm_decl = TREE_VALUE (tuple);
6048 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
6049 if (TREE_CODE (parm_decl) == PARM_DECL
6050 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
6051 parm_decl = error_mark_node;
6052 default_value = tsubst_template_arg (default_value, args,
6053 complain, NULL_TREE);
6055 tuple = build_tree_list (default_value, parm_decl);
6056 TREE_VEC_ELT (new_vec, i) = tuple;
6060 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6061 - TMPL_ARGS_DEPTH (args)),
6062 new_vec, NULL_TREE);
6065 --processing_template_decl;
6070 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6071 type T. If T is not an aggregate or enumeration type, it is
6072 handled as if by tsubst. IN_DECL is as for tsubst. If
6073 ENTERING_SCOPE is nonzero, T is the context for a template which
6074 we are presently tsubst'ing. Return the substituted value. */
6077 tsubst_aggr_type (tree t,
6079 tsubst_flags_t complain,
6086 switch (TREE_CODE (t))
6089 if (TYPE_PTRMEMFUNC_P (t))
6090 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6092 /* Else fall through. */
6095 if (TYPE_TEMPLATE_INFO (t))
6100 bool saved_skip_evaluation;
6102 /* In "sizeof(X<I>)" we need to evaluate "I". */
6103 saved_skip_evaluation = skip_evaluation;
6104 skip_evaluation = false;
6106 /* First, determine the context for the type we are looking
6108 context = TYPE_CONTEXT (t);
6110 context = tsubst_aggr_type (context, args, complain,
6111 in_decl, /*entering_scope=*/1);
6113 /* Then, figure out what arguments are appropriate for the
6114 type we are trying to find. For example, given:
6116 template <class T> struct S;
6117 template <class T, class U> void f(T, U) { S<U> su; }
6119 and supposing that we are instantiating f<int, double>,
6120 then our ARGS will be {int, double}, but, when looking up
6121 S we only want {double}. */
6122 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6124 if (argvec == error_mark_node)
6125 r = error_mark_node;
6128 r = lookup_template_class (t, argvec, in_decl, context,
6129 entering_scope, complain);
6130 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6133 skip_evaluation = saved_skip_evaluation;
6138 /* This is not a template type, so there's nothing to do. */
6142 return tsubst (t, args, complain, in_decl);
6146 /* Substitute into the default argument ARG (a default argument for
6147 FN), which has the indicated TYPE. */
6150 tsubst_default_argument (tree fn, tree type, tree arg)
6152 tree saved_class_ptr = NULL_TREE;
6153 tree saved_class_ref = NULL_TREE;
6155 /* This default argument came from a template. Instantiate the
6156 default argument here, not in tsubst. In the case of
6165 we must be careful to do name lookup in the scope of S<T>,
6166 rather than in the current class. */
6167 push_access_scope (fn);
6168 /* The "this" pointer is not valid in a default argument. */
6171 saved_class_ptr = current_class_ptr;
6172 cp_function_chain->x_current_class_ptr = NULL_TREE;
6173 saved_class_ref = current_class_ref;
6174 cp_function_chain->x_current_class_ref = NULL_TREE;
6177 push_deferring_access_checks(dk_no_deferred);
6178 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6179 tf_error | tf_warning, NULL_TREE);
6180 pop_deferring_access_checks();
6182 /* Restore the "this" pointer. */
6185 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6186 cp_function_chain->x_current_class_ref = saved_class_ref;
6189 pop_access_scope (fn);
6191 /* Make sure the default argument is reasonable. */
6192 arg = check_default_argument (type, arg);
6197 /* Substitute into all the default arguments for FN. */
6200 tsubst_default_arguments (tree fn)
6205 tmpl_args = DECL_TI_ARGS (fn);
6207 /* If this function is not yet instantiated, we certainly don't need
6208 its default arguments. */
6209 if (uses_template_parms (tmpl_args))
6212 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6214 arg = TREE_CHAIN (arg))
6215 if (TREE_PURPOSE (arg))
6216 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6218 TREE_PURPOSE (arg));
6221 /* Substitute the ARGS into the T, which is a _DECL. Return the
6222 result of the substitution. Issue error and warning messages under
6223 control of COMPLAIN. */
6226 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6228 location_t saved_loc;
6232 /* Set the filename and linenumber to improve error-reporting. */
6233 saved_loc = input_location;
6234 input_location = DECL_SOURCE_LOCATION (t);
6236 switch (TREE_CODE (t))
6240 /* We can get here when processing a member function template,
6241 member class template, and template template parameter of
6242 a template class. */
6243 tree decl = DECL_TEMPLATE_RESULT (t);
6248 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6250 /* Template template parameter is treated here. */
6251 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6252 if (new_type == error_mark_node)
6253 return error_mark_node;
6256 TREE_CHAIN (r) = NULL_TREE;
6257 TREE_TYPE (r) = new_type;
6258 DECL_TEMPLATE_RESULT (r)
6259 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6260 DECL_TEMPLATE_PARMS (r)
6261 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6263 TYPE_NAME (new_type) = r;
6267 /* We might already have an instance of this template.
6268 The ARGS are for the surrounding class type, so the
6269 full args contain the tsubst'd args for the context,
6270 plus the innermost args from the template decl. */
6271 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6272 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6273 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6274 /* Because this is a template, the arguments will still be
6275 dependent, even after substitution. If
6276 PROCESSING_TEMPLATE_DECL is not set, the dependency
6277 predicates will short-circuit. */
6278 ++processing_template_decl;
6279 full_args = tsubst_template_args (tmpl_args, args,
6281 --processing_template_decl;
6282 if (full_args == error_mark_node)
6283 return error_mark_node;
6285 /* tsubst_template_args doesn't copy the vector if
6286 nothing changed. But, *something* should have
6288 gcc_assert (full_args != tmpl_args);
6290 spec = retrieve_specialization (t, full_args,
6291 /*class_specializations_p=*/true);
6292 if (spec != NULL_TREE)
6298 /* Make a new template decl. It will be similar to the
6299 original, but will record the current template arguments.
6300 We also create a new function declaration, which is just
6301 like the old one, but points to this new template, rather
6302 than the old one. */
6304 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6305 TREE_CHAIN (r) = NULL_TREE;
6307 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6309 if (TREE_CODE (decl) == TYPE_DECL)
6312 ++processing_template_decl;
6313 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6314 --processing_template_decl;
6315 if (new_type == error_mark_node)
6316 return error_mark_node;
6318 TREE_TYPE (r) = new_type;
6319 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6320 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6321 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6322 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
6327 ++processing_template_decl;
6328 new_decl = tsubst (decl, args, complain, in_decl);
6329 --processing_template_decl;
6330 if (new_decl == error_mark_node)
6331 return error_mark_node;
6333 DECL_TEMPLATE_RESULT (r) = new_decl;
6334 DECL_TI_TEMPLATE (new_decl) = r;
6335 TREE_TYPE (r) = TREE_TYPE (new_decl);
6336 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6337 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
6340 SET_DECL_IMPLICIT_INSTANTIATION (r);
6341 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6342 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6344 /* The template parameters for this new template are all the
6345 template parameters for the old template, except the
6346 outermost level of parameters. */
6347 DECL_TEMPLATE_PARMS (r)
6348 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6351 if (PRIMARY_TEMPLATE_P (t))
6352 DECL_PRIMARY_TEMPLATE (r) = r;
6354 if (TREE_CODE (decl) != TYPE_DECL)
6355 /* Record this non-type partial instantiation. */
6356 register_specialization (r, t,
6357 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
6365 tree argvec = NULL_TREE;
6373 /* Nobody should be tsubst'ing into non-template functions. */
6374 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6376 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6381 /* If T is not dependent, just return it. We have to
6382 increment PROCESSING_TEMPLATE_DECL because
6383 value_dependent_expression_p assumes that nothing is
6384 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6385 ++processing_template_decl;
6386 dependent_p = value_dependent_expression_p (t);
6387 --processing_template_decl;
6391 /* Calculate the most general template of which R is a
6392 specialization, and the complete set of arguments used to
6394 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6395 argvec = tsubst_template_args (DECL_TI_ARGS
6396 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6397 args, complain, in_decl);
6399 /* Check to see if we already have this specialization. */
6400 spec = retrieve_specialization (gen_tmpl, argvec,
6401 /*class_specializations_p=*/false);
6409 /* We can see more levels of arguments than parameters if
6410 there was a specialization of a member template, like
6413 template <class T> struct S { template <class U> void f(); }
6414 template <> template <class U> void S<int>::f(U);
6416 Here, we'll be substituting into the specialization,
6417 because that's where we can find the code we actually
6418 want to generate, but we'll have enough arguments for
6419 the most general template.
6421 We also deal with the peculiar case:
6423 template <class T> struct S {
6424 template <class U> friend void f();
6426 template <class U> void f() {}
6428 template void f<double>();
6430 Here, the ARGS for the instantiation of will be {int,
6431 double}. But, we only need as many ARGS as there are
6432 levels of template parameters in CODE_PATTERN. We are
6433 careful not to get fooled into reducing the ARGS in
6436 template <class T> struct S { template <class U> void f(U); }
6437 template <class T> template <> void S<T>::f(int) {}
6439 which we can spot because the pattern will be a
6440 specialization in this case. */
6441 args_depth = TMPL_ARGS_DEPTH (args);
6443 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6444 if (args_depth > parms_depth
6445 && !DECL_TEMPLATE_SPECIALIZATION (t))
6446 args = get_innermost_template_args (args, parms_depth);
6450 /* This special case arises when we have something like this:
6452 template <class T> struct S {
6453 friend void f<int>(int, double);
6456 Here, the DECL_TI_TEMPLATE for the friend declaration
6457 will be an IDENTIFIER_NODE. We are being called from
6458 tsubst_friend_function, and we want only to create a
6459 new decl (R) with appropriate types so that we can call
6460 determine_specialization. */
6461 gen_tmpl = NULL_TREE;
6464 if (DECL_CLASS_SCOPE_P (t))
6466 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6470 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6471 complain, t, /*entering_scope=*/1);
6476 ctx = DECL_CONTEXT (t);
6478 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6479 if (type == error_mark_node)
6480 return error_mark_node;
6482 /* We do NOT check for matching decls pushed separately at this
6483 point, as they may not represent instantiations of this
6484 template, and in any case are considered separate under the
6487 DECL_USE_TEMPLATE (r) = 0;
6488 TREE_TYPE (r) = type;
6489 /* Clear out the mangled name and RTL for the instantiation. */
6490 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6491 SET_DECL_RTL (r, NULL_RTX);
6492 DECL_INITIAL (r) = NULL_TREE;
6493 DECL_CONTEXT (r) = ctx;
6495 if (member && DECL_CONV_FN_P (r))
6496 /* Type-conversion operator. Reconstruct the name, in
6497 case it's the name of one of the template's parameters. */
6498 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6500 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6502 DECL_RESULT (r) = NULL_TREE;
6504 TREE_STATIC (r) = 0;
6505 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6506 DECL_EXTERNAL (r) = 1;
6507 /* If this is an instantiation of a function with internal
6508 linkage, we already know what object file linkage will be
6509 assigned to the instantiation. */
6510 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6511 DECL_DEFER_OUTPUT (r) = 0;
6512 TREE_CHAIN (r) = NULL_TREE;
6513 DECL_PENDING_INLINE_INFO (r) = 0;
6514 DECL_PENDING_INLINE_P (r) = 0;
6515 DECL_SAVED_TREE (r) = NULL_TREE;
6517 if (DECL_CLONED_FUNCTION (r))
6519 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6521 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6522 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6525 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6526 this in the special friend case mentioned above where
6527 GEN_TMPL is NULL. */
6530 DECL_TEMPLATE_INFO (r)
6531 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6532 SET_DECL_IMPLICIT_INSTANTIATION (r);
6533 register_specialization (r, gen_tmpl, argvec, false);
6535 /* We're not supposed to instantiate default arguments
6536 until they are called, for a template. But, for a
6539 template <class T> void f ()
6540 { extern void g(int i = T()); }
6542 we should do the substitution when the template is
6543 instantiated. We handle the member function case in
6544 instantiate_class_template since the default arguments
6545 might refer to other members of the class. */
6547 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6548 && !uses_template_parms (argvec))
6549 tsubst_default_arguments (r);
6552 DECL_TEMPLATE_INFO (r) = NULL_TREE;
6554 /* Copy the list of befriending classes. */
6555 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6557 friends = &TREE_CHAIN (*friends))
6559 *friends = copy_node (*friends);
6560 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6565 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6567 maybe_retrofit_in_chrg (r);
6568 if (DECL_CONSTRUCTOR_P (r))
6569 grok_ctor_properties (ctx, r);
6570 /* If this is an instantiation of a member template, clone it.
6571 If it isn't, that'll be handled by
6572 clone_constructors_and_destructors. */
6573 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6574 clone_function_decl (r, /*update_method_vec_p=*/0);
6576 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6577 grok_op_properties (r, (complain & tf_error) != 0);
6579 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6580 SET_DECL_FRIEND_CONTEXT (r,
6581 tsubst (DECL_FRIEND_CONTEXT (t),
6582 args, complain, in_decl));
6591 if (DECL_TEMPLATE_PARM_P (t))
6592 SET_DECL_TEMPLATE_PARM_P (r);
6594 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6595 type = type_decays_to (type);
6596 TREE_TYPE (r) = type;
6597 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6599 if (DECL_INITIAL (r))
6601 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6602 DECL_INITIAL (r) = TREE_TYPE (r);
6604 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6608 DECL_CONTEXT (r) = NULL_TREE;
6610 if (!DECL_TEMPLATE_PARM_P (r))
6611 DECL_ARG_TYPE (r) = type_passed_as (type);
6613 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6614 complain, TREE_CHAIN (t));
6623 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6624 if (type == error_mark_node)
6625 return error_mark_node;
6626 TREE_TYPE (r) = type;
6627 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6629 /* We don't have to set DECL_CONTEXT here; it is set by
6630 finish_member_declaration. */
6631 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6633 TREE_CHAIN (r) = NULL_TREE;
6634 if (VOID_TYPE_P (type))
6635 error ("instantiation of %q+D as type %qT", r, type);
6640 /* We reach here only for member using decls. */
6641 if (DECL_DEPENDENT_P (t))
6643 r = do_class_using_decl
6644 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
6645 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
6647 r = error_mark_node;
6652 TREE_CHAIN (r) = NULL_TREE;
6659 tree argvec = NULL_TREE;
6660 tree gen_tmpl = NULL_TREE;
6662 tree tmpl = NULL_TREE;
6664 tree type = NULL_TREE;
6667 if (TREE_CODE (t) == TYPE_DECL)
6669 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6670 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6671 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6673 /* If this is the canonical decl, we don't have to
6674 mess with instantiations, and often we can't (for
6675 typename, template type parms and such). Note that
6676 TYPE_NAME is not correct for the above test if
6677 we've copied the type for a typedef. */
6678 r = TYPE_NAME (type);
6683 /* Assume this is a non-local variable. */
6686 if (TYPE_P (CP_DECL_CONTEXT (t)))
6687 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6689 in_decl, /*entering_scope=*/1);
6690 else if (DECL_NAMESPACE_SCOPE_P (t))
6691 ctx = DECL_CONTEXT (t);
6694 /* Subsequent calls to pushdecl will fill this in. */
6699 /* Check to see if we already have this specialization. */
6702 tmpl = DECL_TI_TEMPLATE (t);
6703 gen_tmpl = most_general_template (tmpl);
6704 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6705 spec = retrieve_specialization (gen_tmpl, argvec,
6706 /*class_specializations_p=*/false);
6709 spec = retrieve_local_specialization (t);
6718 if (TREE_CODE (r) == VAR_DECL)
6720 /* Even if the original location is out of scope, the
6721 newly substituted one is not. */
6722 DECL_DEAD_FOR_LOCAL (r) = 0;
6723 DECL_INITIALIZED_P (r) = 0;
6724 DECL_TEMPLATE_INSTANTIATED (r) = 0;
6725 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6726 if (type == error_mark_node)
6727 return error_mark_node;
6728 type = complete_type (type);
6729 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6730 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6731 type = check_var_type (DECL_NAME (r), type);
6733 if (DECL_HAS_VALUE_EXPR_P (t))
6735 tree ve = DECL_VALUE_EXPR (t);
6736 ve = tsubst_expr (ve, args, complain, in_decl);
6737 SET_DECL_VALUE_EXPR (r, ve);
6740 else if (DECL_SELF_REFERENCE_P (t))
6741 SET_DECL_SELF_REFERENCE_P (r);
6742 TREE_TYPE (r) = type;
6743 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6744 DECL_CONTEXT (r) = ctx;
6745 /* Clear out the mangled name and RTL for the instantiation. */
6746 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6747 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6748 SET_DECL_RTL (r, NULL_RTX);
6749 /* The initializer must not be expanded until it is required;
6751 DECL_INITIAL (r) = NULL_TREE;
6752 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6753 SET_DECL_RTL (r, NULL_RTX);
6754 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6758 /* A static data member declaration is always marked
6759 external when it is declared in-class, even if an
6760 initializer is present. We mimic the non-template
6762 DECL_EXTERNAL (r) = 1;
6764 register_specialization (r, gen_tmpl, argvec, false);
6765 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6766 SET_DECL_IMPLICIT_INSTANTIATION (r);
6769 register_local_specialization (r, t);
6771 TREE_CHAIN (r) = NULL_TREE;
6780 /* Restore the file and line information. */
6781 input_location = saved_loc;
6786 /* Substitute into the ARG_TYPES of a function type. */
6789 tsubst_arg_types (tree arg_types,
6791 tsubst_flags_t complain,
6794 tree remaining_arg_types;
6797 tree result = NULL_TREE;
6799 if (!arg_types || arg_types == void_list_node)
6802 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6803 args, complain, in_decl);
6804 if (remaining_arg_types == error_mark_node)
6805 return error_mark_node;
6807 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6808 if (type == error_mark_node)
6809 return error_mark_node;
6810 if (VOID_TYPE_P (type))
6812 if (complain & tf_error)
6814 error ("invalid parameter type %qT", type);
6816 error ("in declaration %q+D", in_decl);
6818 return error_mark_node;
6821 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6822 top-level qualifiers as required. */
6823 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6825 /* We do not substitute into default arguments here. The standard
6826 mandates that they be instantiated only when needed, which is
6827 done in build_over_call. */
6828 default_arg = TREE_PURPOSE (arg_types);
6830 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
6832 /* We've instantiated a template before its default arguments
6833 have been parsed. This can happen for a nested template
6834 class, and is not an error unless we require the default
6835 argument in a call of this function. */
6836 result = tree_cons (default_arg, type, remaining_arg_types);
6837 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
6840 result = hash_tree_cons (default_arg, type, remaining_arg_types);
6845 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6846 *not* handle the exception-specification for FNTYPE, because the
6847 initial substitution of explicitly provided template parameters
6848 during argument deduction forbids substitution into the
6849 exception-specification:
6853 All references in the function type of the function template to the
6854 corresponding template parameters are replaced by the specified tem-
6855 plate argument values. If a substitution in a template parameter or
6856 in the function type of the function template results in an invalid
6857 type, type deduction fails. [Note: The equivalent substitution in
6858 exception specifications is done only when the function is instanti-
6859 ated, at which point a program is ill-formed if the substitution
6860 results in an invalid type.] */
6863 tsubst_function_type (tree t,
6865 tsubst_flags_t complain,
6872 /* The TYPE_CONTEXT is not used for function/method types. */
6873 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6875 /* Substitute the return type. */
6876 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6877 if (return_type == error_mark_node)
6878 return error_mark_node;
6879 /* The standard does not presently indicate that creation of a
6880 function type with an invalid return type is a deduction failure.
6881 However, that is clearly analogous to creating an array of "void"
6882 or a reference to a reference. This is core issue #486. */
6883 if (TREE_CODE (return_type) == ARRAY_TYPE
6884 || TREE_CODE (return_type) == FUNCTION_TYPE)
6886 if (complain & tf_error)
6888 if (TREE_CODE (return_type) == ARRAY_TYPE)
6889 error ("function returning an array");
6891 error ("function returning a function");
6893 return error_mark_node;
6896 /* Substitute the argument types. */
6897 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6899 if (arg_types == error_mark_node)
6900 return error_mark_node;
6902 /* Construct a new type node and return it. */
6903 if (TREE_CODE (t) == FUNCTION_TYPE)
6904 fntype = build_function_type (return_type, arg_types);
6907 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6908 if (! IS_AGGR_TYPE (r))
6912 Type deduction may fail for any of the following
6915 -- Attempting to create "pointer to member of T" when T
6916 is not a class type. */
6917 if (complain & tf_error)
6918 error ("creating pointer to member function of non-class type %qT",
6920 return error_mark_node;
6923 fntype = build_method_type_directly (r, return_type,
6924 TREE_CHAIN (arg_types));
6926 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6927 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6932 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6933 ARGS into that specification, and return the substituted
6934 specification. If there is no specification, return NULL_TREE. */
6937 tsubst_exception_specification (tree fntype,
6939 tsubst_flags_t complain,
6945 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6946 new_specs = NULL_TREE;
6949 if (! TREE_VALUE (specs))
6955 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6956 if (spec == error_mark_node)
6958 new_specs = add_exception_specifier (new_specs, spec, complain);
6959 specs = TREE_CHAIN (specs);
6965 /* Take the tree structure T and replace template parameters used
6966 therein with the argument vector ARGS. IN_DECL is an associated
6967 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6968 Issue error and warning messages under control of COMPLAIN. Note
6969 that we must be relatively non-tolerant of extensions here, in
6970 order to preserve conformance; if we allow substitutions that
6971 should not be allowed, we may allow argument deductions that should
6972 not succeed, and therefore report ambiguous overload situations
6973 where there are none. In theory, we could allow the substitution,
6974 but indicate that it should have failed, and allow our caller to
6975 make sure that the right thing happens, but we don't try to do this
6978 This function is used for dealing with types, decls and the like;
6979 for expressions, use tsubst_expr or tsubst_copy. */
6982 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6986 if (t == NULL_TREE || t == error_mark_node
6987 || t == integer_type_node
6988 || t == void_type_node
6989 || t == char_type_node
6990 || t == unknown_type_node
6991 || TREE_CODE (t) == NAMESPACE_DECL)
6995 return tsubst_decl (t, args, complain);
6997 if (TREE_CODE (t) == IDENTIFIER_NODE)
6998 type = IDENTIFIER_TYPE_VALUE (t);
7000 type = TREE_TYPE (t);
7002 gcc_assert (type != unknown_type_node);
7005 && TREE_CODE (t) != TYPENAME_TYPE
7006 && TREE_CODE (t) != IDENTIFIER_NODE
7007 && TREE_CODE (t) != FUNCTION_TYPE
7008 && TREE_CODE (t) != METHOD_TYPE)
7009 type = tsubst (type, args, complain, in_decl);
7010 if (type == error_mark_node)
7011 return error_mark_node;
7013 switch (TREE_CODE (t))
7018 return tsubst_aggr_type (t, args, complain, in_decl,
7019 /*entering_scope=*/0);
7022 case IDENTIFIER_NODE:
7034 if (t == integer_type_node)
7037 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
7038 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
7042 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
7044 /* The array dimension behaves like a non-type template arg,
7045 in that we want to fold it as much as possible. */
7046 max = tsubst_template_arg (omax, args, complain, in_decl);
7047 max = fold_decl_constant_value (max);
7051 Type deduction may fail for any of the following
7054 Attempting to create an array with a size that is
7055 zero or negative. */
7056 if (integer_zerop (max) && !(complain & tf_error))
7057 /* We must fail if performing argument deduction (as
7058 indicated by the state of complain), so that
7059 another substitution can be found. */
7060 return error_mark_node;
7062 else if (TREE_CODE (max) == INTEGER_CST
7063 && INT_CST_LT (max, integer_zero_node))
7065 if (complain & tf_error)
7066 error ("creating array with negative size (%qE)", max);
7068 return error_mark_node;
7071 return compute_array_index_type (NULL_TREE, max);
7074 case TEMPLATE_TYPE_PARM:
7075 case TEMPLATE_TEMPLATE_PARM:
7076 case BOUND_TEMPLATE_TEMPLATE_PARM:
7077 case TEMPLATE_PARM_INDEX:
7082 tree arg = NULL_TREE;
7086 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7087 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7088 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7089 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7091 idx = TEMPLATE_TYPE_IDX (t);
7092 level = TEMPLATE_TYPE_LEVEL (t);
7096 idx = TEMPLATE_PARM_IDX (t);
7097 level = TEMPLATE_PARM_LEVEL (t);
7100 levels = TMPL_ARGS_DEPTH (args);
7101 if (level <= levels)
7102 arg = TMPL_ARG (args, level, idx);
7104 if (arg == error_mark_node)
7105 return error_mark_node;
7106 else if (arg != NULL_TREE)
7108 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7110 gcc_assert (TYPE_P (arg));
7111 return cp_build_qualified_type_real
7112 (arg, cp_type_quals (arg) | cp_type_quals (t),
7113 complain | tf_ignore_bad_quals);
7115 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7117 /* We are processing a type constructed from a
7118 template template parameter. */
7119 tree argvec = tsubst (TYPE_TI_ARGS (t),
7120 args, complain, in_decl);
7121 if (argvec == error_mark_node)
7122 return error_mark_node;
7124 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7125 are resolving nested-types in the signature of a
7126 member function templates. Otherwise ARG is a
7127 TEMPLATE_DECL and is the real template to be
7129 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7130 arg = TYPE_NAME (arg);
7132 r = lookup_template_class (arg,
7135 /*entering_scope=*/0,
7137 return cp_build_qualified_type_real
7138 (r, TYPE_QUALS (t), complain);
7141 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7146 /* This can happen during the attempted tsubst'ing in
7147 unify. This means that we don't yet have any information
7148 about the template parameter in question. */
7151 /* If we get here, we must have been looking at a parm for a
7152 more deeply nested template. Make a new version of this
7153 template parameter, but with a lower level. */
7154 switch (TREE_CODE (t))
7156 case TEMPLATE_TYPE_PARM:
7157 case TEMPLATE_TEMPLATE_PARM:
7158 case BOUND_TEMPLATE_TEMPLATE_PARM:
7159 if (cp_type_quals (t))
7161 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7162 r = cp_build_qualified_type_real
7163 (r, cp_type_quals (t),
7164 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7165 ? tf_ignore_bad_quals : 0));
7170 TEMPLATE_TYPE_PARM_INDEX (r)
7171 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7173 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7174 TYPE_MAIN_VARIANT (r) = r;
7175 TYPE_POINTER_TO (r) = NULL_TREE;
7176 TYPE_REFERENCE_TO (r) = NULL_TREE;
7178 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7180 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7182 if (argvec == error_mark_node)
7183 return error_mark_node;
7185 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7186 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7191 case TEMPLATE_PARM_INDEX:
7192 r = reduce_template_parm_level (t, type, levels);
7204 tree purpose, value, chain;
7206 if (t == void_list_node)
7209 purpose = TREE_PURPOSE (t);
7212 purpose = tsubst (purpose, args, complain, in_decl);
7213 if (purpose == error_mark_node)
7214 return error_mark_node;
7216 value = TREE_VALUE (t);
7219 value = tsubst (value, args, complain, in_decl);
7220 if (value == error_mark_node)
7221 return error_mark_node;
7223 chain = TREE_CHAIN (t);
7224 if (chain && chain != void_type_node)
7226 chain = tsubst (chain, args, complain, in_decl);
7227 if (chain == error_mark_node)
7228 return error_mark_node;
7230 if (purpose == TREE_PURPOSE (t)
7231 && value == TREE_VALUE (t)
7232 && chain == TREE_CHAIN (t))
7234 return hash_tree_cons (purpose, value, chain);
7238 /* We should never be tsubsting a binfo. */
7242 /* A vector of template arguments. */
7244 return tsubst_template_args (t, args, complain, in_decl);
7247 case REFERENCE_TYPE:
7249 enum tree_code code;
7251 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7254 code = TREE_CODE (t);
7259 Type deduction may fail for any of the following
7262 -- Attempting to create a pointer to reference type.
7263 -- Attempting to create a reference to a reference type or
7264 a reference to void. */
7265 if (TREE_CODE (type) == REFERENCE_TYPE
7266 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7268 static location_t last_loc;
7270 /* We keep track of the last time we issued this error
7271 message to avoid spewing a ton of messages during a
7272 single bad template instantiation. */
7273 if (complain & tf_error
7274 #ifdef USE_MAPPED_LOCATION
7275 && last_loc != input_location
7277 && (last_loc.line != input_line
7278 || last_loc.file != input_filename)
7282 if (TREE_CODE (type) == VOID_TYPE)
7283 error ("forming reference to void");
7285 error ("forming %s to reference type %qT",
7286 (code == POINTER_TYPE) ? "pointer" : "reference",
7288 last_loc = input_location;
7291 return error_mark_node;
7293 else if (code == POINTER_TYPE)
7295 r = build_pointer_type (type);
7296 if (TREE_CODE (type) == METHOD_TYPE)
7297 r = build_ptrmemfunc_type (r);
7300 r = build_reference_type (type);
7301 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7303 if (r != error_mark_node)
7304 /* Will this ever be needed for TYPE_..._TO values? */
7311 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7312 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7316 Type deduction may fail for any of the following
7319 -- Attempting to create "pointer to member of T" when T
7320 is not a class type. */
7321 if (complain & tf_error)
7322 error ("creating pointer to member of non-class type %qT", r);
7323 return error_mark_node;
7325 if (TREE_CODE (type) == REFERENCE_TYPE)
7327 if (complain & tf_error)
7328 error ("creating pointer to member reference type %qT", type);
7329 return error_mark_node;
7331 if (TREE_CODE (type) == VOID_TYPE)
7333 if (complain & tf_error)
7334 error ("creating pointer to member of type void");
7335 return error_mark_node;
7337 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7338 if (TREE_CODE (type) == FUNCTION_TYPE)
7340 /* The type of the implicit object parameter gets its
7341 cv-qualifiers from the FUNCTION_TYPE. */
7343 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7344 cp_type_quals (type));
7346 method_type = build_method_type_directly (this_type,
7348 TYPE_ARG_TYPES (type));
7349 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7350 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7354 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7363 fntype = tsubst_function_type (t, args, complain, in_decl);
7364 if (fntype == error_mark_node)
7365 return error_mark_node;
7367 /* Substitute the exception specification. */
7368 specs = tsubst_exception_specification (t, args, complain,
7370 if (specs == error_mark_node)
7371 return error_mark_node;
7373 fntype = build_exception_variant (fntype, specs);
7378 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7379 if (domain == error_mark_node)
7380 return error_mark_node;
7382 /* As an optimization, we avoid regenerating the array type if
7383 it will obviously be the same as T. */
7384 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7387 /* These checks should match the ones in grokdeclarator.
7391 The deduction may fail for any of the following reasons:
7393 -- Attempting to create an array with an element type that
7394 is void, a function type, or a reference type, or [DR337]
7395 an abstract class type. */
7396 if (TREE_CODE (type) == VOID_TYPE
7397 || TREE_CODE (type) == FUNCTION_TYPE
7398 || TREE_CODE (type) == REFERENCE_TYPE)
7400 if (complain & tf_error)
7401 error ("creating array of %qT", type);
7402 return error_mark_node;
7404 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7406 if (complain & tf_error)
7407 error ("creating array of %qT, which is an abstract class type",
7409 return error_mark_node;
7412 r = build_cplus_array_type (type, domain);
7419 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7420 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7422 if (e1 == error_mark_node || e2 == error_mark_node)
7423 return error_mark_node;
7425 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7431 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7432 if (e == error_mark_node)
7433 return error_mark_node;
7435 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7440 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7441 in_decl, /*entering_scope=*/1);
7442 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7445 if (ctx == error_mark_node || f == error_mark_node)
7446 return error_mark_node;
7448 if (!IS_AGGR_TYPE (ctx))
7450 if (complain & tf_error)
7451 error ("%qT is not a class, struct, or union type", ctx);
7452 return error_mark_node;
7454 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7456 /* Normally, make_typename_type does not require that the CTX
7457 have complete type in order to allow things like:
7459 template <class T> struct S { typename S<T>::X Y; };
7461 But, such constructs have already been resolved by this
7462 point, so here CTX really should have complete type, unless
7463 it's a partial instantiation. */
7464 ctx = complete_type (ctx);
7465 if (!COMPLETE_TYPE_P (ctx))
7467 if (complain & tf_error)
7468 cxx_incomplete_type_error (NULL_TREE, ctx);
7469 return error_mark_node;
7473 f = make_typename_type (ctx, f, typename_type,
7474 (complain & tf_error) | tf_keep_type_decl);
7475 if (f == error_mark_node)
7477 if (TREE_CODE (f) == TYPE_DECL)
7479 complain |= tf_ignore_bad_quals;
7483 if (TREE_CODE (f) != TYPENAME_TYPE)
7485 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7486 error ("%qT resolves to %qT, which is not an enumeration type",
7488 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7489 error ("%qT resolves to %qT, which is is not a class type",
7493 return cp_build_qualified_type_real
7494 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7497 case UNBOUND_CLASS_TEMPLATE:
7499 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7500 in_decl, /*entering_scope=*/1);
7501 tree name = TYPE_IDENTIFIER (t);
7502 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7504 if (ctx == error_mark_node || name == error_mark_node)
7505 return error_mark_node;
7508 parm_list = tsubst_template_parms (parm_list, args, complain);
7509 return make_unbound_class_template (ctx, name, parm_list, complain);
7519 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7520 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7521 if (e1 == error_mark_node || e2 == error_mark_node)
7522 return error_mark_node;
7524 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7529 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7530 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7531 if (e1 == error_mark_node || e2 == error_mark_node)
7532 return error_mark_node;
7534 return build_qualified_name (/*type=*/NULL_TREE,
7535 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
7542 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7543 complain, in_decl));
7544 return cp_build_qualified_type_real (type,
7546 | cp_type_quals (type),
7551 sorry ("use of %qs in template",
7552 tree_code_name [(int) TREE_CODE (t)]);
7553 return error_mark_node;
7557 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7558 type of the expression on the left-hand side of the "." or "->"
7562 tsubst_baselink (tree baselink, tree object_type,
7563 tree args, tsubst_flags_t complain, tree in_decl)
7566 tree qualifying_scope;
7568 tree template_args = 0;
7569 bool template_id_p = false;
7571 /* A baselink indicates a function from a base class. The
7572 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7573 non-dependent types; otherwise, the lookup could not have
7574 succeeded. However, they may indicate bases of the template
7575 class, rather than the instantiated class.
7577 In addition, lookups that were not ambiguous before may be
7578 ambiguous now. Therefore, we perform the lookup again. */
7579 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7580 fns = BASELINK_FUNCTIONS (baselink);
7581 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7583 template_id_p = true;
7584 template_args = TREE_OPERAND (fns, 1);
7585 fns = TREE_OPERAND (fns, 0);
7587 template_args = tsubst_template_args (template_args, args,
7590 name = DECL_NAME (get_first_fn (fns));
7591 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7593 /* If lookup found a single function, mark it as used at this
7594 point. (If it lookup found multiple functions the one selected
7595 later by overload resolution will be marked as used at that
7597 if (BASELINK_P (baselink))
7598 fns = BASELINK_FUNCTIONS (baselink);
7599 if (!template_id_p && !really_overloaded_fn (fns))
7600 mark_used (OVL_CURRENT (fns));
7602 /* Add back the template arguments, if present. */
7603 if (BASELINK_P (baselink) && template_id_p)
7604 BASELINK_FUNCTIONS (baselink)
7605 = build_nt (TEMPLATE_ID_EXPR,
7606 BASELINK_FUNCTIONS (baselink),
7610 object_type = current_class_type;
7611 return adjust_result_of_qualified_name_lookup (baselink,
7616 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7617 true if the qualified-id will be a postfix-expression in-and-of
7618 itself; false if more of the postfix-expression follows the
7619 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7623 tsubst_qualified_id (tree qualified_id, tree args,
7624 tsubst_flags_t complain, tree in_decl,
7625 bool done, bool address_p)
7633 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7635 /* Figure out what name to look up. */
7636 name = TREE_OPERAND (qualified_id, 1);
7637 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7640 template_args = TREE_OPERAND (name, 1);
7642 template_args = tsubst_template_args (template_args, args,
7644 name = TREE_OPERAND (name, 0);
7648 is_template = false;
7649 template_args = NULL_TREE;
7652 /* Substitute into the qualifying scope. When there are no ARGS, we
7653 are just trying to simplify a non-dependent expression. In that
7654 case the qualifying scope may be dependent, and, in any case,
7655 substituting will not help. */
7656 scope = TREE_OPERAND (qualified_id, 0);
7659 scope = tsubst (scope, args, complain, in_decl);
7660 expr = tsubst_copy (name, args, complain, in_decl);
7665 if (dependent_type_p (scope))
7666 return build_qualified_name (/*type=*/NULL_TREE,
7668 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
7670 if (!BASELINK_P (name) && !DECL_P (expr))
7672 if (TREE_CODE (expr) == BIT_NOT_EXPR)
7673 /* If this were actually a destructor call, it would have been
7674 parsed as such by the parser. */
7675 expr = error_mark_node;
7677 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7678 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7679 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7681 if (complain & tf_error)
7683 error ("dependent-name %qE is parsed as a non-type, but "
7684 "instantiation yields a type", qualified_id);
7685 inform ("say %<typename %E%> if a type is meant", qualified_id);
7687 return error_mark_node;
7693 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7695 /* Remember that there was a reference to this entity. */
7699 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7701 if (complain & tf_error)
7702 qualified_name_lookup_error (scope,
7703 TREE_OPERAND (qualified_id, 1),
7705 return error_mark_node;
7709 expr = lookup_template_function (expr, template_args);
7711 if (expr == error_mark_node && complain & tf_error)
7712 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7714 else if (TYPE_P (scope))
7716 expr = (adjust_result_of_qualified_name_lookup
7717 (expr, scope, current_class_type));
7718 expr = (finish_qualified_id_expr
7719 (scope, expr, done, address_p,
7720 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
7721 /*template_arg_p=*/false));
7724 if (TREE_CODE (expr) != SCOPE_REF)
7725 expr = convert_from_reference (expr);
7730 /* Like tsubst, but deals with expressions. This function just replaces
7731 template parms; to finish processing the resultant expression, use
7735 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7737 enum tree_code code;
7740 if (t == NULL_TREE || t == error_mark_node)
7743 code = TREE_CODE (t);
7748 r = retrieve_local_specialization (t);
7749 gcc_assert (r != NULL);
7758 if (DECL_TEMPLATE_PARM_P (t))
7759 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7760 /* There is no need to substitute into namespace-scope
7762 if (DECL_NAMESPACE_SCOPE_P (t))
7764 /* If ARGS is NULL, then T is known to be non-dependent. */
7765 if (args == NULL_TREE)
7766 return integral_constant_value (t);
7768 /* Unfortunately, we cannot just call lookup_name here.
7771 template <int I> int f() {
7773 struct S { void g() { E e = a; } };
7776 When we instantiate f<7>::S::g(), say, lookup_name is not
7777 clever enough to find f<7>::a. */
7779 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7780 /*entering_scope=*/0);
7782 for (v = TYPE_VALUES (enum_type);
7785 if (TREE_PURPOSE (v) == DECL_NAME (t))
7786 return TREE_VALUE (v);
7788 /* We didn't find the name. That should never happen; if
7789 name-lookup found it during preliminary parsing, we
7790 should find it again here during instantiation. */
7796 if (DECL_CONTEXT (t))
7800 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7801 /*entering_scope=*/1);
7802 if (ctx != DECL_CONTEXT (t))
7804 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7807 if (complain & tf_error)
7808 error ("using invalid field %qD", t);
7809 return error_mark_node;
7819 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7820 || local_variable_p (t))
7821 t = tsubst (t, args, complain, in_decl);
7826 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7829 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7830 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7831 args, complain, in_decl);
7832 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7833 return tsubst (t, args, complain, in_decl);
7834 else if (DECL_CLASS_SCOPE_P (t)
7835 && uses_template_parms (DECL_CONTEXT (t)))
7837 /* Template template argument like the following example need
7840 template <template <class> class TT> struct C {};
7841 template <class T> struct D {
7842 template <class U> struct E {};
7847 We are processing the template argument `E' in #1 for
7848 the template instantiation #2. Originally, `E' is a
7849 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7850 have to substitute this with one having context `D<int>'. */
7852 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7853 return lookup_field (context, DECL_NAME(t), 0, false);
7856 /* Ordinary template template argument. */
7860 case REINTERPRET_CAST_EXPR:
7861 case CONST_CAST_EXPR:
7862 case STATIC_CAST_EXPR:
7863 case DYNAMIC_CAST_EXPR:
7866 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7867 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7871 case TRUTH_NOT_EXPR:
7874 case UNARY_PLUS_EXPR: /* Unary + */
7883 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7884 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7891 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7892 name = TREE_OPERAND (t, 1);
7893 if (TREE_CODE (name) == BIT_NOT_EXPR)
7895 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7897 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7899 else if (TREE_CODE (name) == SCOPE_REF
7900 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7902 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7904 name = TREE_OPERAND (name, 1);
7905 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7907 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7908 name = build_qualified_name (/*type=*/NULL_TREE,
7910 /*template_p=*/false);
7912 else if (TREE_CODE (name) == BASELINK)
7913 name = tsubst_baselink (name,
7914 non_reference (TREE_TYPE (object)),
7918 name = tsubst_copy (name, args, complain, in_decl);
7919 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7925 case TRUNC_DIV_EXPR:
7927 case FLOOR_DIV_EXPR:
7928 case ROUND_DIV_EXPR:
7929 case EXACT_DIV_EXPR:
7933 case TRUNC_MOD_EXPR:
7934 case FLOOR_MOD_EXPR:
7935 case TRUTH_ANDIF_EXPR:
7936 case TRUTH_ORIF_EXPR:
7937 case TRUTH_AND_EXPR:
7954 case PREDECREMENT_EXPR:
7955 case PREINCREMENT_EXPR:
7956 case POSTDECREMENT_EXPR:
7957 case POSTINCREMENT_EXPR:
7959 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7960 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7963 return build_qualified_name (/*type=*/NULL_TREE,
7964 tsubst_copy (TREE_OPERAND (t, 0),
7965 args, complain, in_decl),
7966 tsubst_copy (TREE_OPERAND (t, 1),
7967 args, complain, in_decl),
7968 QUALIFIED_NAME_IS_TEMPLATE (t));
7973 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7974 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7975 NULL_TREE, NULL_TREE);
7978 return build_nt (code,
7979 tsubst_copy (TREE_OPERAND (t, 0), args,
7981 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7987 case PSEUDO_DTOR_EXPR:
7990 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7991 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7992 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7993 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8000 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8001 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
8002 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
8003 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
8010 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8011 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
8012 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
8013 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
8017 case TEMPLATE_ID_EXPR:
8019 /* Substituted template arguments */
8020 tree fn = TREE_OPERAND (t, 0);
8021 tree targs = TREE_OPERAND (t, 1);
8023 fn = tsubst_copy (fn, args, complain, in_decl);
8025 targs = tsubst_template_args (targs, args, complain, in_decl);
8027 return lookup_template_function (fn, targs);
8032 tree purpose, value, chain;
8034 if (t == void_list_node)
8037 purpose = TREE_PURPOSE (t);
8039 purpose = tsubst_copy (purpose, args, complain, in_decl);
8040 value = TREE_VALUE (t);
8042 value = tsubst_copy (value, args, complain, in_decl);
8043 chain = TREE_CHAIN (t);
8044 if (chain && chain != void_type_node)
8045 chain = tsubst_copy (chain, args, complain, in_decl);
8046 if (purpose == TREE_PURPOSE (t)
8047 && value == TREE_VALUE (t)
8048 && chain == TREE_CHAIN (t))
8050 return tree_cons (purpose, value, chain);
8057 case TEMPLATE_TYPE_PARM:
8058 case TEMPLATE_TEMPLATE_PARM:
8059 case BOUND_TEMPLATE_TEMPLATE_PARM:
8060 case TEMPLATE_PARM_INDEX:
8062 case REFERENCE_TYPE:
8068 case UNBOUND_CLASS_TEMPLATE:
8071 return tsubst (t, args, complain, in_decl);
8073 case IDENTIFIER_NODE:
8074 if (IDENTIFIER_TYPENAME_P (t))
8076 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8077 return mangle_conv_op_name_for_type (new_type);
8083 /* This is handled by tsubst_copy_and_build. */
8087 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8089 tsubst (TREE_TYPE (t), args, complain, in_decl));
8091 case CLEANUP_POINT_EXPR:
8092 /* We shouldn't have built any of these during initial template
8093 generation. Instead, they should be built during instantiation
8094 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8098 mark_used (TREE_OPERAND (t, 1));
8106 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
8109 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
8112 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
8114 tree purpose, value, chain;
8119 if (TREE_CODE (t) != TREE_LIST)
8120 return tsubst_copy_and_build (t, args, complain, in_decl,
8121 /*function_p=*/false);
8123 if (t == void_list_node)
8126 purpose = TREE_PURPOSE (t);
8128 purpose = RECUR (purpose);
8129 value = TREE_VALUE (t);
8131 value = RECUR (value);
8132 chain = TREE_CHAIN (t);
8133 if (chain && chain != void_type_node)
8134 chain = RECUR (chain);
8135 return tree_cons (purpose, value, chain);
8139 /* Like tsubst_copy for expressions, etc. but also does semantic
8143 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8147 if (t == NULL_TREE || t == error_mark_node)
8150 if (EXPR_HAS_LOCATION (t))
8151 input_location = EXPR_LOCATION (t);
8152 if (STATEMENT_CODE_P (TREE_CODE (t)))
8153 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8155 switch (TREE_CODE (t))
8157 case STATEMENT_LIST:
8159 tree_stmt_iterator i;
8160 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8161 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8165 case CTOR_INITIALIZER:
8166 finish_mem_initializers (tsubst_initializer_list
8167 (TREE_OPERAND (t, 0), args));
8171 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8172 args, complain, in_decl));
8176 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8177 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8178 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8180 finish_expr_stmt (tmp);
8184 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8185 args, complain, in_decl));
8193 decl = DECL_EXPR_DECL (t);
8194 if (TREE_CODE (decl) == LABEL_DECL)
8195 finish_label_decl (DECL_NAME (decl));
8196 else if (TREE_CODE (decl) == USING_DECL)
8198 tree scope = USING_DECL_SCOPE (decl);
8199 tree name = DECL_NAME (decl);
8202 scope = tsubst_expr (scope, args, complain, in_decl);
8203 decl = lookup_qualified_name (scope, name,
8204 /*is_type_p=*/false,
8205 /*complain=*/false);
8206 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8207 qualified_name_lookup_error (scope, name, decl);
8209 do_local_using_decl (decl, scope, name);
8213 init = DECL_INITIAL (decl);
8214 decl = tsubst (decl, args, complain, in_decl);
8215 if (decl != error_mark_node)
8218 DECL_INITIAL (decl) = error_mark_node;
8219 /* By marking the declaration as instantiated, we avoid
8220 trying to instantiate it. Since instantiate_decl can't
8221 handle local variables, and since we've already done
8222 all that needs to be done, that's the right thing to
8224 if (TREE_CODE (decl) == VAR_DECL)
8225 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8226 if (TREE_CODE (decl) == VAR_DECL
8227 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8228 /* Anonymous aggregates are a special case. */
8229 finish_anon_union (decl);
8232 maybe_push_decl (decl);
8233 if (TREE_CODE (decl) == VAR_DECL
8234 && DECL_PRETTY_FUNCTION_P (decl))
8236 /* For __PRETTY_FUNCTION__ we have to adjust the
8238 const char *const name
8239 = cxx_printable_name (current_function_decl, 2);
8240 init = cp_fname_init (name, &TREE_TYPE (decl));
8243 init = tsubst_expr (init, args, complain, in_decl);
8244 cp_finish_decl (decl, init, NULL_TREE, 0);
8249 /* A DECL_EXPR can also be used as an expression, in the condition
8250 clause of an if/for/while construct. */
8255 stmt = begin_for_stmt ();
8256 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8257 finish_for_init_stmt (stmt);
8258 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8259 finish_for_cond (tmp, stmt);
8260 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8261 finish_for_expr (tmp, stmt);
8262 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8263 finish_for_stmt (stmt);
8267 stmt = begin_while_stmt ();
8268 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8269 finish_while_stmt_cond (tmp, stmt);
8270 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8271 finish_while_stmt (stmt);
8275 stmt = begin_do_stmt ();
8276 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8277 finish_do_body (stmt);
8278 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8279 finish_do_stmt (tmp, stmt);
8283 stmt = begin_if_stmt ();
8284 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8285 finish_if_stmt_cond (tmp, stmt);
8286 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8287 finish_then_clause (stmt);
8289 if (ELSE_CLAUSE (t))
8291 begin_else_clause (stmt);
8292 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8293 finish_else_clause (stmt);
8296 finish_if_stmt (stmt);
8300 if (BIND_EXPR_BODY_BLOCK (t))
8301 stmt = begin_function_body ();
8303 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8304 ? BCS_TRY_BLOCK : 0);
8306 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8308 if (BIND_EXPR_BODY_BLOCK (t))
8309 finish_function_body (stmt);
8311 finish_compound_stmt (stmt);
8315 finish_break_stmt ();
8319 finish_continue_stmt ();
8323 stmt = begin_switch_stmt ();
8324 tmp = tsubst_expr (SWITCH_STMT_COND (t), args, complain, in_decl);
8325 finish_switch_cond (tmp, stmt);
8326 tsubst_expr (SWITCH_STMT_BODY (t), args, complain, in_decl);
8327 finish_switch_stmt (stmt);
8330 case CASE_LABEL_EXPR:
8331 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8332 tsubst_expr (CASE_HIGH (t), args, complain,
8337 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8341 tmp = GOTO_DESTINATION (t);
8342 if (TREE_CODE (tmp) != LABEL_DECL)
8343 /* Computed goto's must be tsubst'd into. On the other hand,
8344 non-computed gotos must not be; the identifier in question
8345 will have no binding. */
8346 tmp = tsubst_expr (tmp, args, complain, in_decl);
8348 tmp = DECL_NAME (tmp);
8349 finish_goto_stmt (tmp);
8353 tmp = finish_asm_stmt
8354 (ASM_VOLATILE_P (t),
8355 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8356 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
8357 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
8358 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl));
8360 tree asm_expr = tmp;
8361 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8362 asm_expr = TREE_OPERAND (asm_expr, 0);
8363 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8370 stmt = begin_try_block ();
8371 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8372 finish_cleanup_try_block (stmt);
8373 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8379 if (FN_TRY_BLOCK_P (t))
8380 stmt = begin_function_try_block ();
8382 stmt = begin_try_block ();
8384 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8386 if (FN_TRY_BLOCK_P (t))
8387 finish_function_try_block (stmt);
8389 finish_try_block (stmt);
8391 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8392 if (FN_TRY_BLOCK_P (t))
8393 finish_function_handler_sequence (stmt);
8395 finish_handler_sequence (stmt);
8403 stmt = begin_handler ();
8404 if (HANDLER_PARMS (t))
8406 decl = HANDLER_PARMS (t);
8407 decl = tsubst (decl, args, complain, in_decl);
8408 /* Prevent instantiate_decl from trying to instantiate
8409 this variable. We've already done all that needs to be
8411 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8415 finish_handler_parms (decl, stmt);
8416 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8417 finish_handler (stmt);
8422 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8426 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8428 return tsubst_copy_and_build (t, args, complain, in_decl,
8429 /*function_p=*/false);
8435 /* T is a postfix-expression that is not being used in a function
8436 call. Return the substituted version of T. */
8439 tsubst_non_call_postfix_expression (tree t, tree args,
8440 tsubst_flags_t complain,
8443 if (TREE_CODE (t) == SCOPE_REF)
8444 t = tsubst_qualified_id (t, args, complain, in_decl,
8445 /*done=*/false, /*address_p=*/false);
8447 t = tsubst_copy_and_build (t, args, complain, in_decl,
8448 /*function_p=*/false);
8453 /* Like tsubst but deals with expressions and performs semantic
8454 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8457 tsubst_copy_and_build (tree t,
8459 tsubst_flags_t complain,
8463 #define RECUR(NODE) \
8464 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8468 if (t == NULL_TREE || t == error_mark_node)
8471 switch (TREE_CODE (t))
8476 case IDENTIFIER_NODE:
8480 bool non_integral_constant_expression_p;
8481 const char *error_msg;
8483 if (IDENTIFIER_TYPENAME_P (t))
8485 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8486 t = mangle_conv_op_name_for_type (new_type);
8489 /* Look up the name. */
8490 decl = lookup_name (t);
8492 /* By convention, expressions use ERROR_MARK_NODE to indicate
8493 failure, not NULL_TREE. */
8494 if (decl == NULL_TREE)
8495 decl = error_mark_node;
8497 decl = finish_id_expression (t, decl, NULL_TREE,
8499 /*integral_constant_expression_p=*/false,
8500 /*allow_non_integral_constant_expression_p=*/false,
8501 &non_integral_constant_expression_p,
8502 /*template_p=*/false,
8504 /*address_p=*/false,
8505 /*template_arg_p=*/false,
8509 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8510 decl = unqualified_name_lookup_error (decl);
8514 case TEMPLATE_ID_EXPR:
8517 tree template = RECUR (TREE_OPERAND (t, 0));
8518 tree targs = TREE_OPERAND (t, 1);
8521 targs = tsubst_template_args (targs, args, complain, in_decl);
8523 if (TREE_CODE (template) == COMPONENT_REF)
8525 object = TREE_OPERAND (template, 0);
8526 template = TREE_OPERAND (template, 1);
8530 template = lookup_template_function (template, targs);
8533 return build3 (COMPONENT_REF, TREE_TYPE (template),
8534 object, template, NULL_TREE);
8541 tree r = RECUR (TREE_OPERAND (t, 0));
8543 if (REFERENCE_REF_P (t))
8545 /* A type conversion to reference type will be enclosed in
8546 such an indirect ref, but the substitution of the cast
8547 will have also added such an indirect ref. */
8548 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8549 r = convert_from_reference (r);
8552 r = build_x_indirect_ref (r, "unary *");
8558 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8559 RECUR (TREE_OPERAND (t, 0)));
8562 return build_functional_cast
8563 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8564 RECUR (TREE_OPERAND (t, 0)));
8566 case REINTERPRET_CAST_EXPR:
8567 return build_reinterpret_cast
8568 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8569 RECUR (TREE_OPERAND (t, 0)));
8571 case CONST_CAST_EXPR:
8572 return build_const_cast
8573 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8574 RECUR (TREE_OPERAND (t, 0)));
8576 case DYNAMIC_CAST_EXPR:
8577 return build_dynamic_cast
8578 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8579 RECUR (TREE_OPERAND (t, 0)));
8581 case STATIC_CAST_EXPR:
8582 return build_static_cast
8583 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8584 RECUR (TREE_OPERAND (t, 0)));
8586 case POSTDECREMENT_EXPR:
8587 case POSTINCREMENT_EXPR:
8588 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8589 args, complain, in_decl);
8590 return build_x_unary_op (TREE_CODE (t), op1);
8592 case PREDECREMENT_EXPR:
8593 case PREINCREMENT_EXPR:
8597 case TRUTH_NOT_EXPR:
8598 case UNARY_PLUS_EXPR: /* Unary + */
8601 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8604 op1 = TREE_OPERAND (t, 0);
8605 if (TREE_CODE (op1) == SCOPE_REF)
8606 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8607 /*done=*/true, /*address_p=*/true);
8609 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8611 if (TREE_CODE (op1) == LABEL_DECL)
8612 return finish_label_address_expr (DECL_NAME (op1));
8613 return build_x_unary_op (ADDR_EXPR, op1);
8618 case TRUNC_DIV_EXPR:
8620 case FLOOR_DIV_EXPR:
8621 case ROUND_DIV_EXPR:
8622 case EXACT_DIV_EXPR:
8626 case TRUNC_MOD_EXPR:
8627 case FLOOR_MOD_EXPR:
8628 case TRUTH_ANDIF_EXPR:
8629 case TRUTH_ORIF_EXPR:
8630 case TRUTH_AND_EXPR:
8646 return build_x_binary_op
8648 RECUR (TREE_OPERAND (t, 0)),
8649 RECUR (TREE_OPERAND (t, 1)),
8650 /*overloaded_p=*/NULL);
8653 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8654 /*address_p=*/false);
8656 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8657 args, complain, in_decl);
8658 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8659 /*overloaded_p=*/NULL);
8663 op1 = TREE_OPERAND (t, 0);
8666 /* When there are no ARGS, we are trying to evaluate a
8667 non-dependent expression from the parser. Trying to do
8668 the substitutions may not work. */
8670 op1 = TREE_TYPE (op1);
8679 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8681 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8685 tree r = build_x_modify_expr
8686 (RECUR (TREE_OPERAND (t, 0)),
8687 TREE_CODE (TREE_OPERAND (t, 1)),
8688 RECUR (TREE_OPERAND (t, 2)));
8689 /* TREE_NO_WARNING must be set if either the expression was
8690 parenthesized or it uses an operator such as >>= rather
8691 than plain assignment. In the former case, it was already
8692 set and must be copied. In the latter case,
8693 build_x_modify_expr sets it and it must not be reset
8695 if (TREE_NO_WARNING (t))
8696 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8701 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8702 args, complain, in_decl);
8703 /* Remember that there was a reference to this entity. */
8706 return build_x_arrow (op1);
8710 (RECUR (TREE_OPERAND (t, 0)),
8711 RECUR (TREE_OPERAND (t, 1)),
8712 RECUR (TREE_OPERAND (t, 2)),
8713 RECUR (TREE_OPERAND (t, 3)),
8714 NEW_EXPR_USE_GLOBAL (t));
8717 return delete_sanity
8718 (RECUR (TREE_OPERAND (t, 0)),
8719 RECUR (TREE_OPERAND (t, 1)),
8720 DELETE_EXPR_USE_VEC (t),
8721 DELETE_EXPR_USE_GLOBAL (t));
8724 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8725 RECUR (TREE_OPERAND (t, 1)));
8734 function = TREE_OPERAND (t, 0);
8735 /* When we parsed the expression, we determined whether or
8736 not Koenig lookup should be performed. */
8737 koenig_p = KOENIG_LOOKUP_P (t);
8738 if (TREE_CODE (function) == SCOPE_REF)
8741 function = tsubst_qualified_id (function, args, complain, in_decl,
8743 /*address_p=*/false);
8747 if (TREE_CODE (function) == COMPONENT_REF)
8749 tree op = TREE_OPERAND (function, 1);
8751 qualified_p = (TREE_CODE (op) == SCOPE_REF
8753 && BASELINK_QUALIFIED_P (op)));
8756 qualified_p = false;
8758 function = tsubst_copy_and_build (function, args, complain,
8761 if (BASELINK_P (function))
8765 call_args = RECUR (TREE_OPERAND (t, 1));
8767 /* We do not perform argument-dependent lookup if normal
8768 lookup finds a non-function, in accordance with the
8769 expected resolution of DR 218. */
8771 && ((is_overloaded_fn (function)
8772 /* If lookup found a member function, the Koenig lookup is
8773 not appropriate, even if an unqualified-name was used
8774 to denote the function. */
8775 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8776 || TREE_CODE (function) == IDENTIFIER_NODE))
8777 function = perform_koenig_lookup (function, call_args);
8779 if (TREE_CODE (function) == IDENTIFIER_NODE)
8781 unqualified_name_lookup_error (function);
8782 return error_mark_node;
8785 /* Remember that there was a reference to this entity. */
8786 if (DECL_P (function))
8787 mark_used (function);
8789 if (TREE_CODE (function) == OFFSET_REF)
8790 return build_offset_ref_call_from_tree (function, call_args);
8791 if (TREE_CODE (function) == COMPONENT_REF)
8793 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8794 return finish_call_expr (function, call_args,
8795 /*disallow_virtual=*/false,
8796 /*koenig_p=*/false);
8798 return (build_new_method_call
8799 (TREE_OPERAND (function, 0),
8800 TREE_OPERAND (function, 1),
8801 call_args, NULL_TREE,
8802 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8804 return finish_call_expr (function, call_args,
8805 /*disallow_virtual=*/qualified_p,
8810 return build_x_conditional_expr
8811 (RECUR (TREE_OPERAND (t, 0)),
8812 RECUR (TREE_OPERAND (t, 1)),
8813 RECUR (TREE_OPERAND (t, 2)));
8815 case PSEUDO_DTOR_EXPR:
8816 return finish_pseudo_destructor_expr
8817 (RECUR (TREE_OPERAND (t, 0)),
8818 RECUR (TREE_OPERAND (t, 1)),
8819 RECUR (TREE_OPERAND (t, 2)));
8823 tree purpose, value, chain;
8825 if (t == void_list_node)
8828 purpose = TREE_PURPOSE (t);
8830 purpose = RECUR (purpose);
8831 value = TREE_VALUE (t);
8833 value = RECUR (value);
8834 chain = TREE_CHAIN (t);
8835 if (chain && chain != void_type_node)
8836 chain = RECUR (chain);
8837 if (purpose == TREE_PURPOSE (t)
8838 && value == TREE_VALUE (t)
8839 && chain == TREE_CHAIN (t))
8841 return tree_cons (purpose, value, chain);
8850 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8851 args, complain, in_decl);
8852 /* Remember that there was a reference to this entity. */
8853 if (DECL_P (object))
8855 object_type = TREE_TYPE (object);
8857 member = TREE_OPERAND (t, 1);
8858 if (BASELINK_P (member))
8859 member = tsubst_baselink (member,
8860 non_reference (TREE_TYPE (object)),
8861 args, complain, in_decl);
8863 member = tsubst_copy (member, args, complain, in_decl);
8864 if (member == error_mark_node)
8865 return error_mark_node;
8867 if (object_type && !CLASS_TYPE_P (object_type))
8869 if (TREE_CODE (member) == BIT_NOT_EXPR)
8870 return finish_pseudo_destructor_expr (object,
8873 else if (TREE_CODE (member) == SCOPE_REF
8874 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8875 return finish_pseudo_destructor_expr (object,
8879 else if (TREE_CODE (member) == SCOPE_REF
8880 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8885 /* Lookup the template functions now that we know what the
8887 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8888 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8889 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8890 /*is_type_p=*/false,
8891 /*complain=*/false);
8892 if (BASELINK_P (member))
8894 BASELINK_FUNCTIONS (member)
8895 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8897 member = (adjust_result_of_qualified_name_lookup
8898 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8903 qualified_name_lookup_error (object_type, tmpl, member);
8904 return error_mark_node;
8907 else if (TREE_CODE (member) == SCOPE_REF
8908 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8909 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8911 if (complain & tf_error)
8913 if (TYPE_P (TREE_OPERAND (member, 0)))
8914 error ("%qT is not a class or namespace",
8915 TREE_OPERAND (member, 0));
8917 error ("%qD is not a class or namespace",
8918 TREE_OPERAND (member, 0));
8920 return error_mark_node;
8922 else if (TREE_CODE (member) == FIELD_DECL)
8923 return finish_non_static_data_member (member, object, NULL_TREE);
8925 return finish_class_member_access_expr (object, member,
8926 /*template_p=*/false);
8931 (RECUR (TREE_OPERAND (t, 0)));
8935 VEC(constructor_elt,gc) *n;
8936 constructor_elt *ce;
8937 unsigned HOST_WIDE_INT idx;
8939 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8940 bool process_index_p;
8942 /* digest_init will do the wrong thing if we let it. */
8943 if (type && TYPE_PTRMEMFUNC_P (type))
8946 /* We do not want to process the index of aggregate
8947 initializers as they are identifier nodes which will be
8948 looked up by digest_init. */
8949 process_index_p = !(type && IS_AGGR_TYPE (type));
8951 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
8952 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
8954 if (ce->index && process_index_p)
8955 ce->index = RECUR (ce->index);
8956 ce->value = RECUR (ce->value);
8959 r = build_constructor (NULL_TREE, n);
8960 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8963 return digest_init (type, r);
8969 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8970 if (TYPE_P (operand_0))
8971 return get_typeid (operand_0);
8972 return build_typeid (operand_0);
8982 tree r = tsubst_copy (t, args, complain, in_decl);
8984 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8985 /* If the original type was a reference, we'll be wrapped in
8986 the appropriate INDIRECT_REF. */
8987 r = convert_from_reference (r);
8992 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8993 tsubst_copy (TREE_TYPE (t), args, complain,
8997 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
9001 tree old_stmt_expr = cur_stmt_expr;
9002 tree stmt_expr = begin_stmt_expr ();
9004 cur_stmt_expr = stmt_expr;
9005 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
9006 stmt_expr = finish_stmt_expr (stmt_expr, false);
9007 cur_stmt_expr = old_stmt_expr;
9013 t = tsubst_copy (t, args, complain, in_decl);
9014 /* As in finish_id_expression, we resolve enumeration constants
9015 to their underlying values. */
9016 if (TREE_CODE (t) == CONST_DECL)
9017 return DECL_INITIAL (t);
9021 /* Handle Objective-C++ constructs, if appropriate. */
9024 = objcp_tsubst_copy_and_build (t, args, complain,
9025 in_decl, /*function_p=*/false);
9029 return tsubst_copy (t, args, complain, in_decl);
9035 /* Verify that the instantiated ARGS are valid. For type arguments,
9036 make sure that the type's linkage is ok. For non-type arguments,
9037 make sure they are constants if they are integral or enumerations.
9038 Emit an error under control of COMPLAIN, and return TRUE on error. */
9041 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
9043 int ix, len = DECL_NTPARMS (tmpl);
9044 bool result = false;
9046 for (ix = 0; ix != len; ix++)
9048 tree t = TREE_VEC_ELT (args, ix);
9052 /* [basic.link]: A name with no linkage (notably, the name
9053 of a class or enumeration declared in a local scope)
9054 shall not be used to declare an entity with linkage.
9055 This implies that names with no linkage cannot be used as
9056 template arguments. */
9057 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
9061 /* DR 488 makes use of a type with no linkage cause
9062 type deduction to fail. */
9063 if (complain & tf_error)
9065 if (TYPE_ANONYMOUS_P (nt))
9066 error ("%qT is/uses anonymous type", t);
9068 error ("template argument for %qD uses local type %qT",
9073 /* In order to avoid all sorts of complications, we do not
9074 allow variably-modified types as template arguments. */
9075 else if (variably_modified_type_p (t, NULL_TREE))
9077 if (complain & tf_error)
9078 error ("%qT is a variably modified type", t);
9082 /* A non-type argument of integral or enumerated type must be a
9084 else if (TREE_TYPE (t)
9085 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
9086 && !TREE_CONSTANT (t))
9088 if (complain & tf_error)
9089 error ("integral expression %qE is not constant", t);
9093 if (result && (complain & tf_error))
9094 error (" trying to instantiate %qD", tmpl);
9098 /* Instantiate the indicated variable or function template TMPL with
9099 the template arguments in TARG_PTR. */
9102 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
9108 if (tmpl == error_mark_node)
9109 return error_mark_node;
9111 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
9113 /* If this function is a clone, handle it specially. */
9114 if (DECL_CLONED_FUNCTION_P (tmpl))
9119 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
9121 if (spec == error_mark_node)
9122 return error_mark_node;
9124 /* Look for the clone. */
9125 FOR_EACH_CLONE (clone, spec)
9126 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9128 /* We should always have found the clone by now. */
9133 /* Check to see if we already have this specialization. */
9134 spec = retrieve_specialization (tmpl, targ_ptr,
9135 /*class_specializations_p=*/false);
9136 if (spec != NULL_TREE)
9139 gen_tmpl = most_general_template (tmpl);
9140 if (tmpl != gen_tmpl)
9142 /* The TMPL is a partial instantiation. To get a full set of
9143 arguments we must add the arguments used to perform the
9144 partial instantiation. */
9145 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9148 /* Check to see if we already have this specialization. */
9149 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9150 /*class_specializations_p=*/false);
9151 if (spec != NULL_TREE)
9155 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9157 return error_mark_node;
9159 /* We are building a FUNCTION_DECL, during which the access of its
9160 parameters and return types have to be checked. However this
9161 FUNCTION_DECL which is the desired context for access checking
9162 is not built yet. We solve this chicken-and-egg problem by
9163 deferring all checks until we have the FUNCTION_DECL. */
9164 push_deferring_access_checks (dk_deferred);
9166 /* Substitute template parameters. */
9167 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9168 targ_ptr, complain, gen_tmpl);
9169 if (fndecl == error_mark_node)
9170 return error_mark_node;
9172 /* Now we know the specialization, compute access previously
9174 push_access_scope (fndecl);
9175 perform_deferred_access_checks ();
9176 pop_access_scope (fndecl);
9177 pop_deferring_access_checks ();
9179 /* The DECL_TI_TEMPLATE should always be the immediate parent
9180 template, not the most general template. */
9181 DECL_TI_TEMPLATE (fndecl) = tmpl;
9183 /* If we've just instantiated the main entry point for a function,
9184 instantiate all the alternate entry points as well. We do this
9185 by cloning the instantiation of the main entry point, not by
9186 instantiating the template clones. */
9187 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9188 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9193 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9194 arguments that are being used when calling it. TARGS is a vector
9195 into which the deduced template arguments are placed.
9197 Return zero for success, 2 for an incomplete match that doesn't resolve
9198 all the types, and 1 for complete failure. An error message will be
9199 printed only for an incomplete match.
9201 If FN is a conversion operator, or we are trying to produce a specific
9202 specialization, RETURN_TYPE is the return type desired.
9204 The EXPLICIT_TARGS are explicit template arguments provided via a
9207 The parameter STRICT is one of:
9210 We are deducing arguments for a function call, as in
9214 We are deducing arguments for a conversion function, as in
9218 We are deducing arguments when doing an explicit instantiation
9219 as in [temp.explicit], when determining an explicit specialization
9220 as in [temp.expl.spec], or when taking the address of a function
9221 template, as in [temp.deduct.funcaddr]. */
9224 fn_type_unification (tree fn,
9225 tree explicit_targs,
9229 unification_kind_t strict,
9236 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9238 fntype = TREE_TYPE (fn);
9243 The specified template arguments must match the template
9244 parameters in kind (i.e., type, nontype, template), and there
9245 must not be more arguments than there are parameters;
9246 otherwise type deduction fails.
9248 Nontype arguments must match the types of the corresponding
9249 nontype template parameters, or must be convertible to the
9250 types of the corresponding nontype parameters as specified in
9251 _temp.arg.nontype_, otherwise type deduction fails.
9253 All references in the function type of the function template
9254 to the corresponding template parameters are replaced by the
9255 specified template argument values. If a substitution in a
9256 template parameter or in the function type of the function
9257 template results in an invalid type, type deduction fails. */
9259 tree converted_args;
9262 if (explicit_targs == error_mark_node)
9266 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9267 explicit_targs, NULL_TREE, tf_none,
9268 /*require_all_arguments=*/0));
9269 if (converted_args == error_mark_node)
9272 /* Substitute the explicit args into the function type. This is
9273 necessary so that, for instance, explicitly declared function
9274 arguments can match null pointed constants. If we were given
9275 an incomplete set of explicit args, we must not do semantic
9276 processing during substitution as we could create partial
9278 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9279 processing_template_decl += incomplete;
9280 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9281 processing_template_decl -= incomplete;
9283 if (fntype == error_mark_node)
9286 /* Place the explicitly specified arguments in TARGS. */
9287 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9288 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9291 parms = TYPE_ARG_TYPES (fntype);
9292 /* Never do unification on the 'this' parameter. */
9293 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9294 parms = TREE_CHAIN (parms);
9298 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9299 args = tree_cons (NULL_TREE, return_type, args);
9302 /* We allow incomplete unification without an error message here
9303 because the standard doesn't seem to explicitly prohibit it. Our
9304 callers must be ready to deal with unification failures in any
9306 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9307 targs, parms, args, /*subr=*/0,
9311 /* All is well so far. Now, check:
9315 When all template arguments have been deduced, all uses of
9316 template parameters in nondeduced contexts are replaced with
9317 the corresponding deduced argument values. If the
9318 substitution results in an invalid type, as described above,
9319 type deduction fails. */
9320 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9327 /* Adjust types before performing type deduction, as described in
9328 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9329 sections are symmetric. PARM is the type of a function parameter
9330 or the return type of the conversion function. ARG is the type of
9331 the argument passed to the call, or the type of the value
9332 initialized with the result of the conversion function. */
9335 maybe_adjust_types_for_deduction (unification_kind_t strict,
9348 /* Swap PARM and ARG throughout the remainder of this
9349 function; the handling is precisely symmetric since PARM
9350 will initialize ARG rather than vice versa. */
9358 /* There is nothing to do in this case. */
9365 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9367 /* [temp.deduct.call]
9369 If P is not a reference type:
9371 --If A is an array type, the pointer type produced by the
9372 array-to-pointer standard conversion (_conv.array_) is
9373 used in place of A for type deduction; otherwise,
9375 --If A is a function type, the pointer type produced by
9376 the function-to-pointer standard conversion
9377 (_conv.func_) is used in place of A for type deduction;
9380 --If A is a cv-qualified type, the top level
9381 cv-qualifiers of A's type are ignored for type
9383 if (TREE_CODE (*arg) == ARRAY_TYPE)
9384 *arg = build_pointer_type (TREE_TYPE (*arg));
9385 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9386 *arg = build_pointer_type (*arg);
9388 *arg = TYPE_MAIN_VARIANT (*arg);
9391 /* [temp.deduct.call]
9393 If P is a cv-qualified type, the top level cv-qualifiers
9394 of P's type are ignored for type deduction. If P is a
9395 reference type, the type referred to by P is used for
9397 *parm = TYPE_MAIN_VARIANT (*parm);
9398 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9400 *parm = TREE_TYPE (*parm);
9401 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9404 /* DR 322. For conversion deduction, remove a reference type on parm
9405 too (which has been swapped into ARG). */
9406 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9407 *arg = TREE_TYPE (*arg);
9412 /* Most parms like fn_type_unification.
9414 If SUBR is 1, we're being called recursively (to unify the
9415 arguments of a function or method parameter of a function
9419 type_unification_real (tree tparms,
9424 unification_kind_t strict,
9429 int ntparms = TREE_VEC_LENGTH (tparms);
9431 int saw_undeduced = 0;
9434 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9435 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9436 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9437 gcc_assert (ntparms > 0);
9442 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9443 | UNIFY_ALLOW_DERIVED);
9447 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9451 sub_strict = UNIFY_ALLOW_NONE;
9462 while (parms && parms != void_list_node
9463 && args && args != void_list_node)
9465 parm = TREE_VALUE (parms);
9466 parms = TREE_CHAIN (parms);
9467 arg = TREE_VALUE (args);
9468 args = TREE_CHAIN (args);
9470 if (arg == error_mark_node)
9472 if (arg == unknown_type_node)
9473 /* We can't deduce anything from this, but we might get all the
9474 template args from other function args. */
9477 /* Conversions will be performed on a function argument that
9478 corresponds with a function parameter that contains only
9479 non-deducible template parameters and explicitly specified
9480 template parameters. */
9481 if (!uses_template_parms (parm))
9486 type = TREE_TYPE (arg);
9490 if (same_type_p (parm, type))
9492 if (strict != DEDUCE_EXACT
9493 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
9502 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9503 if (type_unknown_p (arg))
9505 /* [temp.deduct.type] A template-argument can be deduced from
9506 a pointer to function or pointer to member function
9507 argument if the set of overloaded functions does not
9508 contain function templates and at most one of a set of
9509 overloaded functions provides a unique match. */
9511 if (resolve_overloaded_unification
9512 (tparms, targs, parm, arg, strict, sub_strict)
9517 arg = TREE_TYPE (arg);
9518 if (arg == error_mark_node)
9523 int arg_strict = sub_strict;
9526 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9528 if (unify (tparms, targs, parm, arg, arg_strict))
9533 /* Fail if we've reached the end of the parm list, and more args
9534 are present, and the parm list isn't variadic. */
9535 if (args && args != void_list_node && parms == void_list_node)
9537 /* Fail if parms are left and they don't have default values. */
9538 if (parms && parms != void_list_node
9539 && TREE_PURPOSE (parms) == NULL_TREE)
9543 for (i = 0; i < ntparms; i++)
9544 if (!TREE_VEC_ELT (targs, i))
9546 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9548 /* If this is an undeduced nontype parameter that depends on
9549 a type parameter, try another pass; its type may have been
9550 deduced from a later argument than the one from which
9551 this parameter can be deduced. */
9552 if (TREE_CODE (tparm) == PARM_DECL
9553 && uses_template_parms (TREE_TYPE (tparm))
9554 && !saw_undeduced++)
9563 /* Subroutine of type_unification_real. Args are like the variables at the
9564 call site. ARG is an overloaded function (or template-id); we try
9565 deducing template args from each of the overloads, and if only one
9566 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9569 resolve_overloaded_unification (tree tparms,
9573 unification_kind_t strict,
9576 tree tempargs = copy_node (targs);
9580 if (TREE_CODE (arg) == ADDR_EXPR)
9582 arg = TREE_OPERAND (arg, 0);
9588 if (TREE_CODE (arg) == COMPONENT_REF)
9589 /* Handle `&x' where `x' is some static or non-static member
9591 arg = TREE_OPERAND (arg, 1);
9593 if (TREE_CODE (arg) == OFFSET_REF)
9594 arg = TREE_OPERAND (arg, 1);
9596 /* Strip baselink information. */
9597 if (BASELINK_P (arg))
9598 arg = BASELINK_FUNCTIONS (arg);
9600 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9602 /* If we got some explicit template args, we need to plug them into
9603 the affected templates before we try to unify, in case the
9604 explicit args will completely resolve the templates in question. */
9606 tree expl_subargs = TREE_OPERAND (arg, 1);
9607 arg = TREE_OPERAND (arg, 0);
9609 for (; arg; arg = OVL_NEXT (arg))
9611 tree fn = OVL_CURRENT (arg);
9614 if (TREE_CODE (fn) != TEMPLATE_DECL)
9617 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9618 expl_subargs, /*check_ret=*/false);
9621 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9622 good += try_one_overload (tparms, targs, tempargs, parm,
9623 elem, strict, sub_strict, addr_p);
9629 gcc_assert (TREE_CODE (arg) == OVERLOAD
9630 || TREE_CODE (arg) == FUNCTION_DECL);
9632 for (; arg; arg = OVL_NEXT (arg))
9633 good += try_one_overload (tparms, targs, tempargs, parm,
9634 TREE_TYPE (OVL_CURRENT (arg)),
9635 strict, sub_strict, addr_p);
9638 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9639 to function or pointer to member function argument if the set of
9640 overloaded functions does not contain function templates and at most
9641 one of a set of overloaded functions provides a unique match.
9643 So if we found multiple possibilities, we return success but don't
9648 int i = TREE_VEC_LENGTH (targs);
9650 if (TREE_VEC_ELT (tempargs, i))
9651 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9659 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9660 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9661 different overloads deduce different arguments for a given parm.
9662 ADDR_P is true if the expression for which deduction is being
9663 performed was of the form "& fn" rather than simply "fn".
9665 Returns 1 on success. */
9668 try_one_overload (tree tparms,
9673 unification_kind_t strict,
9681 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9682 to function or pointer to member function argument if the set of
9683 overloaded functions does not contain function templates and at most
9684 one of a set of overloaded functions provides a unique match.
9686 So if this is a template, just return success. */
9688 if (uses_template_parms (arg))
9691 if (TREE_CODE (arg) == METHOD_TYPE)
9692 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9694 arg = build_pointer_type (arg);
9696 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9698 /* We don't copy orig_targs for this because if we have already deduced
9699 some template args from previous args, unify would complain when we
9700 try to deduce a template parameter for the same argument, even though
9701 there isn't really a conflict. */
9702 nargs = TREE_VEC_LENGTH (targs);
9703 tempargs = make_tree_vec (nargs);
9705 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9708 /* First make sure we didn't deduce anything that conflicts with
9709 explicitly specified args. */
9710 for (i = nargs; i--; )
9712 tree elt = TREE_VEC_ELT (tempargs, i);
9713 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9717 else if (uses_template_parms (elt))
9718 /* Since we're unifying against ourselves, we will fill in
9719 template args used in the function parm list with our own
9720 template parms. Discard them. */
9721 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9722 else if (oldelt && !template_args_equal (oldelt, elt))
9726 for (i = nargs; i--; )
9728 tree elt = TREE_VEC_ELT (tempargs, i);
9731 TREE_VEC_ELT (targs, i) = elt;
9737 /* Verify that nondeduce template argument agrees with the type
9738 obtained from argument deduction. Return nonzero if the
9743 struct A { typedef int X; };
9744 template <class T, class U> struct C {};
9745 template <class T> struct C<T, typename T::X> {};
9747 Then with the instantiation `C<A, int>', we can deduce that
9748 `T' is `A' but unify () does not check whether `typename T::X'
9749 is `int'. This function ensure that they agree.
9751 TARGS, PARMS are the same as the arguments of unify.
9752 ARGS contains template arguments from all levels. */
9755 verify_class_unification (tree targs, tree parms, tree args)
9757 parms = tsubst (parms, add_outermost_template_args (args, targs),
9758 tf_none, NULL_TREE);
9759 if (parms == error_mark_node)
9762 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9765 /* PARM is a template class (perhaps with unbound template
9766 parameters). ARG is a fully instantiated type. If ARG can be
9767 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9768 TARGS are as for unify. */
9771 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9775 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9776 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9777 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9780 /* We need to make a new template argument vector for the call to
9781 unify. If we used TARGS, we'd clutter it up with the result of
9782 the attempted unification, even if this class didn't work out.
9783 We also don't want to commit ourselves to all the unifications
9784 we've already done, since unification is supposed to be done on
9785 an argument-by-argument basis. In other words, consider the
9786 following pathological case:
9788 template <int I, int J, int K>
9791 template <int I, int J>
9792 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9794 template <int I, int J, int K>
9795 void f(S<I, J, K>, S<I, I, I>);
9804 Now, by the time we consider the unification involving `s2', we
9805 already know that we must have `f<0, 0, 0>'. But, even though
9806 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9807 because there are two ways to unify base classes of S<0, 1, 2>
9808 with S<I, I, I>. If we kept the already deduced knowledge, we
9809 would reject the possibility I=1. */
9810 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9812 /* If unification failed, we're done. */
9813 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9814 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9820 /* Given a template type PARM and a class type ARG, find the unique
9821 base type in ARG that is an instance of PARM. We do not examine
9822 ARG itself; only its base-classes. If there is not exactly one
9823 appropriate base class, return NULL_TREE. PARM may be the type of
9824 a partial specialization, as well as a plain template type. Used
9828 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9830 tree rval = NULL_TREE;
9833 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9835 binfo = TYPE_BINFO (complete_type (arg));
9837 /* The type could not be completed. */
9840 /* Walk in inheritance graph order. The search order is not
9841 important, and this avoids multiple walks of virtual bases. */
9842 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9844 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9848 /* If there is more than one satisfactory baseclass, then:
9852 If they yield more than one possible deduced A, the type
9856 if (rval && !same_type_p (r, rval))
9866 /* Returns the level of DECL, which declares a template parameter. */
9869 template_decl_level (tree decl)
9871 switch (TREE_CODE (decl))
9875 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9878 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9886 /* Decide whether ARG can be unified with PARM, considering only the
9887 cv-qualifiers of each type, given STRICT as documented for unify.
9888 Returns nonzero iff the unification is OK on that basis. */
9891 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9893 int arg_quals = cp_type_quals (arg);
9894 int parm_quals = cp_type_quals (parm);
9896 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9897 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9899 /* Although a CVR qualifier is ignored when being applied to a
9900 substituted template parameter ([8.3.2]/1 for example), that
9901 does not apply during deduction [14.8.2.4]/1, (even though
9902 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9903 this). Except when we're allowing additional CV qualifiers
9904 at the outer level [14.8.2.1]/3,1st bullet. */
9905 if ((TREE_CODE (arg) == REFERENCE_TYPE
9906 || TREE_CODE (arg) == FUNCTION_TYPE
9907 || TREE_CODE (arg) == METHOD_TYPE)
9908 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9911 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9912 && (parm_quals & TYPE_QUAL_RESTRICT))
9916 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9917 && (arg_quals & parm_quals) != parm_quals)
9920 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9921 && (parm_quals & arg_quals) != arg_quals)
9927 /* Takes parameters as for type_unification. Returns 0 if the
9928 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9929 bitwise or of the following flags:
9932 Require an exact match between PARM and ARG.
9933 UNIFY_ALLOW_MORE_CV_QUAL:
9934 Allow the deduced ARG to be more cv-qualified (by qualification
9935 conversion) than ARG.
9936 UNIFY_ALLOW_LESS_CV_QUAL:
9937 Allow the deduced ARG to be less cv-qualified than ARG.
9938 UNIFY_ALLOW_DERIVED:
9939 Allow the deduced ARG to be a template base class of ARG,
9940 or a pointer to a template base class of the type pointed to by
9942 UNIFY_ALLOW_INTEGER:
9943 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9944 case for more information.
9945 UNIFY_ALLOW_OUTER_LEVEL:
9946 This is the outermost level of a deduction. Used to determine validity
9947 of qualification conversions. A valid qualification conversion must
9948 have const qualified pointers leading up to the inner type which
9949 requires additional CV quals, except at the outer level, where const
9950 is not required [conv.qual]. It would be normal to set this flag in
9951 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9952 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9953 This is the outermost level of a deduction, and PARM can be more CV
9954 qualified at this point.
9955 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9956 This is the outermost level of a deduction, and PARM can be less CV
9957 qualified at this point. */
9960 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9965 int strict_in = strict;
9967 /* I don't think this will do the right thing with respect to types.
9968 But the only case I've seen it in so far has been array bounds, where
9969 signedness is the only information lost, and I think that will be
9971 while (TREE_CODE (parm) == NOP_EXPR)
9972 parm = TREE_OPERAND (parm, 0);
9974 if (arg == error_mark_node)
9976 if (arg == unknown_type_node)
9977 /* We can't deduce anything from this, but we might get all the
9978 template args from other function args. */
9981 /* If PARM uses template parameters, then we can't bail out here,
9982 even if ARG == PARM, since we won't record unifications for the
9983 template parameters. We might need them if we're trying to
9984 figure out which of two things is more specialized. */
9985 if (arg == parm && !uses_template_parms (parm))
9988 /* Immediately reject some pairs that won't unify because of
9989 cv-qualification mismatches. */
9990 if (TREE_CODE (arg) == TREE_CODE (parm)
9992 /* It is the elements of the array which hold the cv quals of an array
9993 type, and the elements might be template type parms. We'll check
9995 && TREE_CODE (arg) != ARRAY_TYPE
9996 /* We check the cv-qualifiers when unifying with template type
9997 parameters below. We want to allow ARG `const T' to unify with
9998 PARM `T' for example, when computing which of two templates
9999 is more specialized, for example. */
10000 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
10001 && !check_cv_quals_for_unify (strict_in, arg, parm))
10004 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
10005 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
10006 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
10007 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
10008 strict &= ~UNIFY_ALLOW_DERIVED;
10009 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
10010 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
10012 switch (TREE_CODE (parm))
10014 case TYPENAME_TYPE:
10016 case UNBOUND_CLASS_TEMPLATE:
10017 /* In a type which contains a nested-name-specifier, template
10018 argument values cannot be deduced for template parameters used
10019 within the nested-name-specifier. */
10022 case TEMPLATE_TYPE_PARM:
10023 case TEMPLATE_TEMPLATE_PARM:
10024 case BOUND_TEMPLATE_TEMPLATE_PARM:
10025 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10027 if (TEMPLATE_TYPE_LEVEL (parm)
10028 != template_decl_level (tparm))
10029 /* The PARM is not one we're trying to unify. Just check
10030 to see if it matches ARG. */
10031 return (TREE_CODE (arg) == TREE_CODE (parm)
10032 && same_type_p (parm, arg)) ? 0 : 1;
10033 idx = TEMPLATE_TYPE_IDX (parm);
10034 targ = TREE_VEC_ELT (targs, idx);
10035 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
10037 /* Check for mixed types and values. */
10038 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
10039 && TREE_CODE (tparm) != TYPE_DECL)
10040 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10041 && TREE_CODE (tparm) != TEMPLATE_DECL))
10044 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10046 /* ARG must be constructed from a template class or a template
10047 template parameter. */
10048 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
10049 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
10053 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
10054 tree parmvec = TYPE_TI_ARGS (parm);
10055 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
10057 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
10060 /* The parameter and argument roles have to be switched here
10061 in order to handle default arguments properly. For example,
10062 template<template <class> class TT> void f(TT<int>)
10063 should be able to accept vector<int> which comes from
10064 template <class T, class Allocator = allocator>
10067 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
10068 == error_mark_node)
10071 /* Deduce arguments T, i from TT<T> or TT<i>.
10072 We check each element of PARMVEC and ARGVEC individually
10073 rather than the whole TREE_VEC since they can have
10074 different number of elements. */
10076 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
10078 if (unify (tparms, targs,
10079 TREE_VEC_ELT (parmvec, i),
10080 TREE_VEC_ELT (argvec, i),
10085 arg = TYPE_TI_TEMPLATE (arg);
10087 /* Fall through to deduce template name. */
10090 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10091 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10093 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
10095 /* Simple cases: Value already set, does match or doesn't. */
10096 if (targ != NULL_TREE && template_args_equal (targ, arg))
10103 /* If PARM is `const T' and ARG is only `int', we don't have
10104 a match unless we are allowing additional qualification.
10105 If ARG is `const int' and PARM is just `T' that's OK;
10106 that binds `const int' to `T'. */
10107 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10111 /* Consider the case where ARG is `const volatile int' and
10112 PARM is `const T'. Then, T should be `volatile int'. */
10113 arg = cp_build_qualified_type_real
10114 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10115 if (arg == error_mark_node)
10118 /* Simple cases: Value already set, does match or doesn't. */
10119 if (targ != NULL_TREE && same_type_p (targ, arg))
10124 /* Make sure that ARG is not a variable-sized array. (Note
10125 that were talking about variable-sized arrays (like
10126 `int[n]'), rather than arrays of unknown size (like
10127 `int[]').) We'll get very confused by such a type since
10128 the bound of the array will not be computable in an
10129 instantiation. Besides, such types are not allowed in
10130 ISO C++, so we can do as we please here. */
10131 if (variably_modified_type_p (arg, NULL_TREE))
10135 TREE_VEC_ELT (targs, idx) = arg;
10138 case TEMPLATE_PARM_INDEX:
10139 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10141 if (TEMPLATE_PARM_LEVEL (parm)
10142 != template_decl_level (tparm))
10143 /* The PARM is not one we're trying to unify. Just check
10144 to see if it matches ARG. */
10145 return !(TREE_CODE (arg) == TREE_CODE (parm)
10146 && cp_tree_equal (parm, arg));
10148 idx = TEMPLATE_PARM_IDX (parm);
10149 targ = TREE_VEC_ELT (targs, idx);
10152 return !cp_tree_equal (targ, arg);
10154 /* [temp.deduct.type] If, in the declaration of a function template
10155 with a non-type template-parameter, the non-type
10156 template-parameter is used in an expression in the function
10157 parameter-list and, if the corresponding template-argument is
10158 deduced, the template-argument type shall match the type of the
10159 template-parameter exactly, except that a template-argument
10160 deduced from an array bound may be of any integral type.
10161 The non-type parameter might use already deduced type parameters. */
10162 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10163 if (!TREE_TYPE (arg))
10164 /* Template-parameter dependent expression. Just accept it for now.
10165 It will later be processed in convert_template_argument. */
10167 else if (same_type_p (TREE_TYPE (arg), tparm))
10169 else if ((strict & UNIFY_ALLOW_INTEGER)
10170 && (TREE_CODE (tparm) == INTEGER_TYPE
10171 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10172 /* Convert the ARG to the type of PARM; the deduced non-type
10173 template argument must exactly match the types of the
10174 corresponding parameter. */
10175 arg = fold (build_nop (TREE_TYPE (parm), arg));
10176 else if (uses_template_parms (tparm))
10177 /* We haven't deduced the type of this parameter yet. Try again
10183 TREE_VEC_ELT (targs, idx) = arg;
10188 /* A pointer-to-member constant can be unified only with
10189 another constant. */
10190 if (TREE_CODE (arg) != PTRMEM_CST)
10193 /* Just unify the class member. It would be useless (and possibly
10194 wrong, depending on the strict flags) to unify also
10195 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10196 arg refer to the same variable, even if through different
10197 classes. For instance:
10199 struct A { int x; };
10202 Unification of &A::x and &B::x must succeed. */
10203 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10204 PTRMEM_CST_MEMBER (arg), strict);
10209 if (TREE_CODE (arg) != POINTER_TYPE)
10212 /* [temp.deduct.call]
10214 A can be another pointer or pointer to member type that can
10215 be converted to the deduced A via a qualification
10216 conversion (_conv.qual_).
10218 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10219 This will allow for additional cv-qualification of the
10220 pointed-to types if appropriate. */
10222 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10223 /* The derived-to-base conversion only persists through one
10224 level of pointers. */
10225 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10227 return unify (tparms, targs, TREE_TYPE (parm),
10228 TREE_TYPE (arg), strict);
10231 case REFERENCE_TYPE:
10232 if (TREE_CODE (arg) != REFERENCE_TYPE)
10234 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10235 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10238 if (TREE_CODE (arg) != ARRAY_TYPE)
10240 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10241 != (TYPE_DOMAIN (arg) == NULL_TREE))
10243 if (TYPE_DOMAIN (parm) != NULL_TREE)
10248 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10249 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10251 /* Our representation of array types uses "N - 1" as the
10252 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10253 not an integer constant. */
10254 if (TREE_CODE (parm_max) == MINUS_EXPR)
10256 arg_max = fold_build2 (PLUS_EXPR,
10259 TREE_OPERAND (parm_max, 1));
10260 parm_max = TREE_OPERAND (parm_max, 0);
10263 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10266 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10267 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10274 case ENUMERAL_TYPE:
10276 if (TREE_CODE (arg) != TREE_CODE (parm))
10279 /* We have already checked cv-qualification at the top of the
10281 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10284 /* As far as unification is concerned, this wins. Later checks
10285 will invalidate it if necessary. */
10288 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10289 /* Type INTEGER_CST can come from ordinary constant template args. */
10291 while (TREE_CODE (arg) == NOP_EXPR)
10292 arg = TREE_OPERAND (arg, 0);
10294 if (TREE_CODE (arg) != INTEGER_CST)
10296 return !tree_int_cst_equal (parm, arg);
10301 if (TREE_CODE (arg) != TREE_VEC)
10303 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10305 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10306 if (unify (tparms, targs,
10307 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10315 if (TREE_CODE (arg) != TREE_CODE (parm))
10318 if (TYPE_PTRMEMFUNC_P (parm))
10320 if (!TYPE_PTRMEMFUNC_P (arg))
10323 return unify (tparms, targs,
10324 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10325 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10329 if (CLASSTYPE_TEMPLATE_INFO (parm))
10331 tree t = NULL_TREE;
10333 if (strict_in & UNIFY_ALLOW_DERIVED)
10335 /* First, we try to unify the PARM and ARG directly. */
10336 t = try_class_unification (tparms, targs,
10341 /* Fallback to the special case allowed in
10342 [temp.deduct.call]:
10344 If P is a class, and P has the form
10345 template-id, then A can be a derived class of
10346 the deduced A. Likewise, if P is a pointer to
10347 a class of the form template-id, A can be a
10348 pointer to a derived class pointed to by the
10350 t = get_template_base (tparms, targs, parm, arg);
10356 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10357 && (CLASSTYPE_TI_TEMPLATE (parm)
10358 == CLASSTYPE_TI_TEMPLATE (arg)))
10359 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10360 Then, we should unify `int' and `U'. */
10363 /* There's no chance of unification succeeding. */
10366 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10367 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10369 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10374 case FUNCTION_TYPE:
10375 if (TREE_CODE (arg) != TREE_CODE (parm))
10378 /* CV qualifications for methods can never be deduced, they must
10379 match exactly. We need to check them explicitly here,
10380 because type_unification_real treats them as any other
10381 cvqualified parameter. */
10382 if (TREE_CODE (parm) == METHOD_TYPE
10383 && (!check_cv_quals_for_unify
10385 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
10386 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
10389 if (unify (tparms, targs, TREE_TYPE (parm),
10390 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10392 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10393 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10397 /* Unify a pointer to member with a pointer to member function, which
10398 deduces the type of the member as a function type. */
10399 if (TYPE_PTRMEMFUNC_P (arg))
10403 cp_cv_quals cv_quals;
10405 /* Check top-level cv qualifiers */
10406 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10409 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10410 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10413 /* Determine the type of the function we are unifying against. */
10414 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10416 build_function_type (TREE_TYPE (method_type),
10417 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10419 /* Extract the cv-qualifiers of the member function from the
10420 implicit object parameter and place them on the function
10421 type to be restored later. */
10423 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10424 fntype = build_qualified_type (fntype, cv_quals);
10425 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10428 if (TREE_CODE (arg) != OFFSET_TYPE)
10430 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10431 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10433 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10437 if (DECL_TEMPLATE_PARM_P (parm))
10438 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10439 if (arg != integral_constant_value (parm))
10444 case TEMPLATE_DECL:
10445 /* Matched cases are handled by the ARG == PARM test above. */
10449 gcc_assert (EXPR_P (parm));
10451 /* We must be looking at an expression. This can happen with
10455 void foo(S<I>, S<I + 2>);
10457 This is a "nondeduced context":
10461 The nondeduced contexts are:
10463 --A type that is a template-id in which one or more of
10464 the template-arguments is an expression that references
10465 a template-parameter.
10467 In these cases, we assume deduction succeeded, but don't
10468 actually infer any unifications. */
10470 if (!uses_template_parms (parm)
10471 && !template_args_equal (parm, arg))
10478 /* Note that DECL can be defined in this translation unit, if
10482 mark_definable (tree decl)
10485 DECL_NOT_REALLY_EXTERN (decl) = 1;
10486 FOR_EACH_CLONE (clone, decl)
10487 DECL_NOT_REALLY_EXTERN (clone) = 1;
10490 /* Called if RESULT is explicitly instantiated, or is a member of an
10491 explicitly instantiated class. */
10494 mark_decl_instantiated (tree result, int extern_p)
10496 SET_DECL_EXPLICIT_INSTANTIATION (result);
10498 /* If this entity has already been written out, it's too late to
10499 make any modifications. */
10500 if (TREE_ASM_WRITTEN (result))
10503 if (TREE_CODE (result) != FUNCTION_DECL)
10504 /* The TREE_PUBLIC flag for function declarations will have been
10505 set correctly by tsubst. */
10506 TREE_PUBLIC (result) = 1;
10508 /* This might have been set by an earlier implicit instantiation. */
10509 DECL_COMDAT (result) = 0;
10512 DECL_NOT_REALLY_EXTERN (result) = 0;
10515 mark_definable (result);
10516 /* Always make artificials weak. */
10517 if (DECL_ARTIFICIAL (result) && flag_weak)
10518 comdat_linkage (result);
10519 /* For WIN32 we also want to put explicit instantiations in
10520 linkonce sections. */
10521 else if (TREE_PUBLIC (result))
10522 maybe_make_one_only (result);
10525 /* If EXTERN_P, then this function will not be emitted -- unless
10526 followed by an explicit instantiation, at which point its linkage
10527 will be adjusted. If !EXTERN_P, then this function will be
10528 emitted here. In neither circumstance do we want
10529 import_export_decl to adjust the linkage. */
10530 DECL_INTERFACE_KNOWN (result) = 1;
10533 /* Given two function templates PAT1 and PAT2, return:
10535 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10536 -1 if PAT2 is more specialized than PAT1.
10537 0 if neither is more specialized.
10539 LEN indicates the number of parameters we should consider
10540 (defaulted parameters should not be considered).
10542 The 1998 std underspecified function template partial ordering, and
10543 DR214 addresses the issue. We take pairs of arguments, one from
10544 each of the templates, and deduce them against each other. One of
10545 the templates will be more specialized if all the *other*
10546 template's arguments deduce against its arguments and at least one
10547 of its arguments *does* *not* deduce against the other template's
10548 corresponding argument. Deduction is done as for class templates.
10549 The arguments used in deduction have reference and top level cv
10550 qualifiers removed. Iff both arguments were originally reference
10551 types *and* deduction succeeds in both directions, the template
10552 with the more cv-qualified argument wins for that pairing (if
10553 neither is more cv-qualified, they both are equal). Unlike regular
10554 deduction, after all the arguments have been deduced in this way,
10555 we do *not* verify the deduced template argument values can be
10556 substituted into non-deduced contexts, nor do we have to verify
10557 that all template arguments have been deduced. */
10560 more_specialized_fn (tree pat1, tree pat2, int len)
10562 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10563 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10564 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10565 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10566 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10567 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10568 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10569 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10573 /* Remove the this parameter from non-static member functions. If
10574 one is a non-static member function and the other is not a static
10575 member function, remove the first parameter from that function
10576 also. This situation occurs for operator functions where we
10577 locate both a member function (with this pointer) and non-member
10578 operator (with explicit first operand). */
10579 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10581 len--; /* LEN is the number of significant arguments for DECL1 */
10582 args1 = TREE_CHAIN (args1);
10583 if (!DECL_STATIC_FUNCTION_P (decl2))
10584 args2 = TREE_CHAIN (args2);
10586 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10588 args2 = TREE_CHAIN (args2);
10589 if (!DECL_STATIC_FUNCTION_P (decl1))
10592 args1 = TREE_CHAIN (args1);
10596 /* If only one is a conversion operator, they are unordered. */
10597 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10600 /* Consider the return type for a conversion function */
10601 if (DECL_CONV_FN_P (decl1))
10603 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10604 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10608 processing_template_decl++;
10612 tree arg1 = TREE_VALUE (args1);
10613 tree arg2 = TREE_VALUE (args2);
10614 int deduce1, deduce2;
10618 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10620 arg1 = TREE_TYPE (arg1);
10621 quals1 = cp_type_quals (arg1);
10624 if (TREE_CODE (arg2) == REFERENCE_TYPE)
10626 arg2 = TREE_TYPE (arg2);
10627 quals2 = cp_type_quals (arg2);
10630 if ((quals1 < 0) != (quals2 < 0))
10632 /* Only of the args is a reference, see if we should apply
10633 array/function pointer decay to it. This is not part of
10634 DR214, but is, IMHO, consistent with the deduction rules
10635 for the function call itself, and with our earlier
10636 implementation of the underspecified partial ordering
10637 rules. (nathan). */
10640 switch (TREE_CODE (arg1))
10643 arg1 = TREE_TYPE (arg1);
10645 case FUNCTION_TYPE:
10646 arg1 = build_pointer_type (arg1);
10655 switch (TREE_CODE (arg2))
10658 arg2 = TREE_TYPE (arg2);
10660 case FUNCTION_TYPE:
10661 arg2 = build_pointer_type (arg2);
10670 arg1 = TYPE_MAIN_VARIANT (arg1);
10671 arg2 = TYPE_MAIN_VARIANT (arg2);
10673 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
10674 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
10680 if (better1 < 0 && better2 < 0)
10681 /* We've failed to deduce something in either direction.
10682 These must be unordered. */
10685 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
10687 /* Deduces in both directions, see if quals can
10688 disambiguate. Pretend the worse one failed to deduce. */
10689 if ((quals1 & quals2) == quals2)
10691 if ((quals1 & quals2) == quals1)
10694 if (deduce1 && !deduce2 && !better2)
10696 if (deduce2 && !deduce1 && !better1)
10699 args1 = TREE_CHAIN (args1);
10700 args2 = TREE_CHAIN (args2);
10703 processing_template_decl--;
10705 return (better1 > 0) - (better2 > 0);
10708 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10710 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10711 -1 if PAT2 is more specialized than PAT1.
10712 0 if neither is more specialized.
10714 FULL_ARGS is the full set of template arguments that triggers this
10715 partial ordering. */
10718 more_specialized_class (tree pat1, tree pat2, tree full_args)
10723 /* Just like what happens for functions, if we are ordering between
10724 different class template specializations, we may encounter dependent
10725 types in the arguments, and we need our dependency check functions
10726 to behave correctly. */
10727 ++processing_template_decl;
10728 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10729 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10733 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10734 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10737 --processing_template_decl;
10742 /* Return the template arguments that will produce the function signature
10743 DECL from the function template FN, with the explicit template
10744 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
10745 also match. Return NULL_TREE if no satisfactory arguments could be
10749 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
10751 int ntparms = DECL_NTPARMS (fn);
10752 tree targs = make_tree_vec (ntparms);
10754 tree decl_arg_types;
10756 /* Substitute the explicit template arguments into the type of DECL.
10757 The call to fn_type_unification will handle substitution into the
10759 decl_type = TREE_TYPE (decl);
10760 if (explicit_args && uses_template_parms (decl_type))
10763 tree converted_args;
10765 if (DECL_TEMPLATE_INFO (decl))
10766 tmpl = DECL_TI_TEMPLATE (decl);
10768 /* We can get here for some invalid specializations. */
10772 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10773 explicit_args, NULL_TREE,
10774 tf_none, /*require_all_arguments=*/0));
10775 if (converted_args == error_mark_node)
10778 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10779 if (decl_type == error_mark_node)
10783 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10784 /* Never do unification on the 'this' parameter. */
10785 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10786 decl_arg_types = TREE_CHAIN (decl_arg_types);
10788 if (fn_type_unification (fn, explicit_args, targs,
10790 (check_rettype || DECL_CONV_FN_P (fn)
10791 ? TREE_TYPE (decl_type) : NULL_TREE),
10792 DEDUCE_EXACT, LOOKUP_NORMAL))
10798 /* Return the innermost template arguments that, when applied to a
10799 template specialization whose innermost template parameters are
10800 TPARMS, and whose specialization arguments are PARMS, yield the
10803 For example, suppose we have:
10805 template <class T, class U> struct S {};
10806 template <class T> struct S<T*, int> {};
10808 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10809 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10810 int}. The resulting vector will be {double}, indicating that `T'
10811 is bound to `double'. */
10814 get_class_bindings (tree tparms, tree parms, tree args)
10816 int i, ntparms = TREE_VEC_LENGTH (tparms);
10817 tree vec = make_tree_vec (ntparms);
10819 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10823 for (i = 0; i < ntparms; ++i)
10824 if (! TREE_VEC_ELT (vec, i))
10827 if (verify_class_unification (vec, parms, args))
10833 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
10834 Return the TREE_LIST node with the most specialized template, if
10835 any. If there is no most specialized template, the error_mark_node
10838 Note that this function does not look at, or modify, the
10839 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
10840 returned is one of the elements of INSTANTIATIONS, callers may
10841 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
10842 and retrieve it from the value returned. */
10845 most_specialized_instantiation (tree templates)
10849 ++processing_template_decl;
10852 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
10856 if (get_bindings (TREE_VALUE (champ),
10857 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10858 NULL_TREE, /*check_ret=*/false))
10861 if (get_bindings (TREE_VALUE (fn),
10862 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10863 NULL_TREE, /*check_ret=*/false))
10870 /* Equally specialized, move to next function. If there
10871 is no next function, nothing's most specialized. */
10872 fn = TREE_CHAIN (fn);
10880 /* Now verify that champ is better than everything earlier in the
10881 instantiation list. */
10882 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
10883 if (get_bindings (TREE_VALUE (champ),
10884 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10885 NULL_TREE, /*check_ret=*/false)
10886 || !get_bindings (TREE_VALUE (fn),
10887 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10888 NULL_TREE, /*check_ret=*/false))
10894 processing_template_decl--;
10897 return error_mark_node;
10902 /* If DECL is a specialization of some template, return the most
10903 general such template. Otherwise, returns NULL_TREE.
10905 For example, given:
10907 template <class T> struct S { template <class U> void f(U); };
10909 if TMPL is `template <class U> void S<int>::f(U)' this will return
10910 the full template. This function will not trace past partial
10911 specializations, however. For example, given in addition:
10913 template <class T> struct S<T*> { template <class U> void f(U); };
10915 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10916 `template <class T> template <class U> S<T*>::f(U)'. */
10919 most_general_template (tree decl)
10921 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10922 an immediate specialization. */
10923 if (TREE_CODE (decl) == FUNCTION_DECL)
10925 if (DECL_TEMPLATE_INFO (decl)) {
10926 decl = DECL_TI_TEMPLATE (decl);
10928 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10929 template friend. */
10930 if (TREE_CODE (decl) != TEMPLATE_DECL)
10936 /* Look for more and more general templates. */
10937 while (DECL_TEMPLATE_INFO (decl))
10939 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10940 (See cp-tree.h for details.) */
10941 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10944 if (CLASS_TYPE_P (TREE_TYPE (decl))
10945 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10948 /* Stop if we run into an explicitly specialized class template. */
10949 if (!DECL_NAMESPACE_SCOPE_P (decl)
10950 && DECL_CONTEXT (decl)
10951 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10954 decl = DECL_TI_TEMPLATE (decl);
10960 /* Return the most specialized of the class template specializations
10961 of TMPL which can produce an instantiation matching ARGS, or
10962 error_mark_node if the choice is ambiguous. */
10965 most_specialized_class (tree tmpl, tree args)
10967 tree list = NULL_TREE;
10972 tmpl = most_general_template (tmpl);
10973 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10976 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10979 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10980 TREE_TYPE (list) = TREE_TYPE (t);
10989 t = TREE_CHAIN (t);
10990 for (; t; t = TREE_CHAIN (t))
10992 fate = more_specialized_class (champ, t, args);
10999 t = TREE_CHAIN (t);
11001 return error_mark_node;
11007 for (t = list; t && t != champ; t = TREE_CHAIN (t))
11009 fate = more_specialized_class (champ, t, args);
11011 return error_mark_node;
11017 /* Explicitly instantiate DECL. */
11020 do_decl_instantiation (tree decl, tree storage)
11022 tree result = NULL_TREE;
11026 /* An error occurred, for which grokdeclarator has already issued
11027 an appropriate message. */
11029 else if (! DECL_LANG_SPECIFIC (decl))
11031 error ("explicit instantiation of non-template %q#D", decl);
11034 else if (TREE_CODE (decl) == VAR_DECL)
11036 /* There is an asymmetry here in the way VAR_DECLs and
11037 FUNCTION_DECLs are handled by grokdeclarator. In the case of
11038 the latter, the DECL we get back will be marked as a
11039 template instantiation, and the appropriate
11040 DECL_TEMPLATE_INFO will be set up. This does not happen for
11041 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
11042 should handle VAR_DECLs as it currently handles
11044 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
11045 if (!result || TREE_CODE (result) != VAR_DECL)
11047 error ("no matching template for %qD found", decl);
11051 else if (TREE_CODE (decl) != FUNCTION_DECL)
11053 error ("explicit instantiation of %q#D", decl);
11059 /* Check for various error cases. Note that if the explicit
11060 instantiation is valid the RESULT will currently be marked as an
11061 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
11062 until we get here. */
11064 if (DECL_TEMPLATE_SPECIALIZATION (result))
11066 /* DR 259 [temp.spec].
11068 Both an explicit instantiation and a declaration of an explicit
11069 specialization shall not appear in a program unless the explicit
11070 instantiation follows a declaration of the explicit specialization.
11072 For a given set of template parameters, if an explicit
11073 instantiation of a template appears after a declaration of an
11074 explicit specialization for that template, the explicit
11075 instantiation has no effect. */
11078 else if (DECL_EXPLICIT_INSTANTIATION (result))
11082 No program shall explicitly instantiate any template more
11085 We check DECL_NOT_REALLY_EXTERN so as not to complain when
11086 the first instantiation was `extern' and the second is not,
11087 and EXTERN_P for the opposite case. */
11088 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
11089 pedwarn ("duplicate explicit instantiation of %q#D", result);
11090 /* If an "extern" explicit instantiation follows an ordinary
11091 explicit instantiation, the template is instantiated. */
11095 else if (!DECL_IMPLICIT_INSTANTIATION (result))
11097 error ("no matching template for %qD found", result);
11100 else if (!DECL_TEMPLATE_INFO (result))
11102 pedwarn ("explicit instantiation of non-template %q#D", result);
11106 if (storage == NULL_TREE)
11108 else if (storage == ridpointers[(int) RID_EXTERN])
11110 if (pedantic && !in_system_header)
11111 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11116 error ("storage class %qD applied to template instantiation", storage);
11118 check_explicit_instantiation_namespace (result);
11119 mark_decl_instantiated (result, extern_p);
11121 instantiate_decl (result, /*defer_ok=*/1,
11122 /*expl_inst_class_mem_p=*/false);
11126 mark_class_instantiated (tree t, int extern_p)
11128 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11129 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11130 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11131 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11134 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11135 rest_of_type_compilation (t, 1);
11139 /* Called from do_type_instantiation through binding_table_foreach to
11140 do recursive instantiation for the type bound in ENTRY. */
11142 bt_instantiate_type_proc (binding_entry entry, void *data)
11144 tree storage = *(tree *) data;
11146 if (IS_AGGR_TYPE (entry->type)
11147 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11148 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11151 /* Called from do_type_instantiation to instantiate a member
11152 (a member function or a static member variable) of an
11153 explicitly instantiated class template. */
11155 instantiate_class_member (tree decl, int extern_p)
11157 mark_decl_instantiated (decl, extern_p);
11159 instantiate_decl (decl, /*defer_ok=*/1,
11160 /*expl_inst_class_mem_p=*/true);
11163 /* Perform an explicit instantiation of template class T. STORAGE, if
11164 non-null, is the RID for extern, inline or static. COMPLAIN is
11165 nonzero if this is called from the parser, zero if called recursively,
11166 since the standard is unclear (as detailed below). */
11169 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11174 int previous_instantiation_extern_p = 0;
11176 if (TREE_CODE (t) == TYPE_DECL)
11179 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11181 error ("explicit instantiation of non-template type %qT", t);
11187 if (!COMPLETE_TYPE_P (t))
11189 if (complain & tf_error)
11190 error ("explicit instantiation of %q#T before definition of template",
11195 if (storage != NULL_TREE)
11197 if (pedantic && !in_system_header)
11198 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11201 if (storage == ridpointers[(int) RID_INLINE])
11203 else if (storage == ridpointers[(int) RID_EXTERN])
11205 else if (storage == ridpointers[(int) RID_STATIC])
11209 error ("storage class %qD applied to template instantiation",
11215 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11217 /* DR 259 [temp.spec].
11219 Both an explicit instantiation and a declaration of an explicit
11220 specialization shall not appear in a program unless the explicit
11221 instantiation follows a declaration of the explicit specialization.
11223 For a given set of template parameters, if an explicit
11224 instantiation of a template appears after a declaration of an
11225 explicit specialization for that template, the explicit
11226 instantiation has no effect. */
11229 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11233 No program shall explicitly instantiate any template more
11236 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11237 instantiation was `extern'. If EXTERN_P then the second is.
11238 These cases are OK. */
11239 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11241 if (!previous_instantiation_extern_p && !extern_p
11242 && (complain & tf_error))
11243 pedwarn ("duplicate explicit instantiation of %q#T", t);
11245 /* If we've already instantiated the template, just return now. */
11246 if (!CLASSTYPE_INTERFACE_ONLY (t))
11250 check_explicit_instantiation_namespace (TYPE_NAME (t));
11251 mark_class_instantiated (t, extern_p);
11259 /* In contrast to implicit instantiation, where only the
11260 declarations, and not the definitions, of members are
11261 instantiated, we have here:
11265 The explicit instantiation of a class template specialization
11266 implies the instantiation of all of its members not
11267 previously explicitly specialized in the translation unit
11268 containing the explicit instantiation.
11270 Of course, we can't instantiate member template classes, since
11271 we don't have any arguments for them. Note that the standard
11272 is unclear on whether the instantiation of the members are
11273 *explicit* instantiations or not. However, the most natural
11274 interpretation is that it should be an explicit instantiation. */
11277 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11278 if (TREE_CODE (tmp) == FUNCTION_DECL
11279 && DECL_TEMPLATE_INSTANTIATION (tmp))
11280 instantiate_class_member (tmp, extern_p);
11282 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11283 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11284 instantiate_class_member (tmp, extern_p);
11286 if (CLASSTYPE_NESTED_UTDS (t))
11287 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11288 bt_instantiate_type_proc, &storage);
11292 /* Given a function DECL, which is a specialization of TMPL, modify
11293 DECL to be a re-instantiation of TMPL with the same template
11294 arguments. TMPL should be the template into which tsubst'ing
11295 should occur for DECL, not the most general template.
11297 One reason for doing this is a scenario like this:
11300 void f(const T&, int i);
11302 void g() { f(3, 7); }
11305 void f(const T& t, const int i) { }
11307 Note that when the template is first instantiated, with
11308 instantiate_template, the resulting DECL will have no name for the
11309 first parameter, and the wrong type for the second. So, when we go
11310 to instantiate the DECL, we regenerate it. */
11313 regenerate_decl_from_template (tree decl, tree tmpl)
11315 /* The arguments used to instantiate DECL, from the most general
11320 args = DECL_TI_ARGS (decl);
11321 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11323 /* Make sure that we can see identifiers, and compute access
11325 push_access_scope (decl);
11327 if (TREE_CODE (decl) == FUNCTION_DECL)
11335 args_depth = TMPL_ARGS_DEPTH (args);
11336 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11337 if (args_depth > parms_depth)
11338 args = get_innermost_template_args (args, parms_depth);
11340 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11341 args, tf_error, NULL_TREE);
11343 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11346 /* Merge parameter declarations. */
11347 decl_parm = skip_artificial_parms_for (decl,
11348 DECL_ARGUMENTS (decl));
11350 = skip_artificial_parms_for (code_pattern,
11351 DECL_ARGUMENTS (code_pattern));
11357 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11358 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11359 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11361 parm_type = type_decays_to (parm_type);
11362 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11363 TREE_TYPE (decl_parm) = parm_type;
11364 attributes = DECL_ATTRIBUTES (pattern_parm);
11365 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11367 DECL_ATTRIBUTES (decl_parm) = attributes;
11368 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11370 decl_parm = TREE_CHAIN (decl_parm);
11371 pattern_parm = TREE_CHAIN (pattern_parm);
11374 /* Merge additional specifiers from the CODE_PATTERN. */
11375 if (DECL_DECLARED_INLINE_P (code_pattern)
11376 && !DECL_DECLARED_INLINE_P (decl))
11377 DECL_DECLARED_INLINE_P (decl) = 1;
11378 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11379 DECL_INLINE (decl) = 1;
11381 else if (TREE_CODE (decl) == VAR_DECL)
11382 DECL_INITIAL (decl) =
11383 tsubst_expr (DECL_INITIAL (code_pattern), args,
11384 tf_error, DECL_TI_TEMPLATE (decl));
11386 gcc_unreachable ();
11388 pop_access_scope (decl);
11391 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11392 substituted to get DECL. */
11395 template_for_substitution (tree decl)
11397 tree tmpl = DECL_TI_TEMPLATE (decl);
11399 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11400 for the instantiation. This is not always the most general
11401 template. Consider, for example:
11404 struct S { template <class U> void f();
11405 template <> void f<int>(); };
11407 and an instantiation of S<double>::f<int>. We want TD to be the
11408 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11409 while (/* An instantiation cannot have a definition, so we need a
11410 more general template. */
11411 DECL_TEMPLATE_INSTANTIATION (tmpl)
11412 /* We must also deal with friend templates. Given:
11414 template <class T> struct S {
11415 template <class U> friend void f() {};
11418 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11419 so far as the language is concerned, but that's still
11420 where we get the pattern for the instantiation from. On
11421 other hand, if the definition comes outside the class, say:
11423 template <class T> struct S {
11424 template <class U> friend void f();
11426 template <class U> friend void f() {}
11428 we don't need to look any further. That's what the check for
11429 DECL_INITIAL is for. */
11430 || (TREE_CODE (decl) == FUNCTION_DECL
11431 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11432 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11434 /* The present template, TD, should not be a definition. If it
11435 were a definition, we should be using it! Note that we
11436 cannot restructure the loop to just keep going until we find
11437 a template with a definition, since that might go too far if
11438 a specialization was declared, but not defined. */
11439 gcc_assert (TREE_CODE (decl) != VAR_DECL
11440 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11442 /* Fetch the more general template. */
11443 tmpl = DECL_TI_TEMPLATE (tmpl);
11449 /* Produce the definition of D, a _DECL generated from a template. If
11450 DEFER_OK is nonzero, then we don't have to actually do the
11451 instantiation now; we just have to do it sometime. Normally it is
11452 an error if this is an explicit instantiation but D is undefined.
11453 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
11454 explicitly instantiated class template. */
11457 instantiate_decl (tree d, int defer_ok,
11458 bool expl_inst_class_mem_p)
11460 tree tmpl = DECL_TI_TEMPLATE (d);
11467 bool pattern_defined;
11469 location_t saved_loc = input_location;
11472 /* This function should only be used to instantiate templates for
11473 functions and static member variables. */
11474 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11475 || TREE_CODE (d) == VAR_DECL);
11477 /* Variables are never deferred; if instantiation is required, they
11478 are instantiated right away. That allows for better code in the
11479 case that an expression refers to the value of the variable --
11480 if the variable has a constant value the referring expression can
11481 take advantage of that fact. */
11482 if (TREE_CODE (d) == VAR_DECL)
11485 /* Don't instantiate cloned functions. Instead, instantiate the
11486 functions they cloned. */
11487 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11488 d = DECL_CLONED_FUNCTION (d);
11490 if (DECL_TEMPLATE_INSTANTIATED (d))
11491 /* D has already been instantiated. It might seem reasonable to
11492 check whether or not D is an explicit instantiation, and, if so,
11493 stop here. But when an explicit instantiation is deferred
11494 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11495 is set, even though we still need to do the instantiation. */
11498 /* If we already have a specialization of this declaration, then
11499 there's no reason to instantiate it. Note that
11500 retrieve_specialization gives us both instantiations and
11501 specializations, so we must explicitly check
11502 DECL_TEMPLATE_SPECIALIZATION. */
11503 gen_tmpl = most_general_template (tmpl);
11504 gen_args = DECL_TI_ARGS (d);
11505 spec = retrieve_specialization (gen_tmpl, gen_args,
11506 /*class_specializations_p=*/false);
11507 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11510 /* This needs to happen before any tsubsting. */
11511 if (! push_tinst_level (d))
11514 timevar_push (TV_PARSE);
11516 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11517 for the instantiation. */
11518 td = template_for_substitution (d);
11519 code_pattern = DECL_TEMPLATE_RESULT (td);
11521 /* We should never be trying to instantiate a member of a class
11522 template or partial specialization. */
11523 gcc_assert (d != code_pattern);
11525 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11526 || DECL_TEMPLATE_SPECIALIZATION (td))
11527 /* In the case of a friend template whose definition is provided
11528 outside the class, we may have too many arguments. Drop the
11529 ones we don't need. The same is true for specializations. */
11530 args = get_innermost_template_args
11531 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11535 if (TREE_CODE (d) == FUNCTION_DECL)
11536 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11538 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11540 /* We may be in the middle of deferred access check. Disable it now. */
11541 push_deferring_access_checks (dk_no_deferred);
11543 /* Unless an explicit instantiation directive has already determined
11544 the linkage of D, remember that a definition is available for
11546 if (pattern_defined
11547 && !DECL_INTERFACE_KNOWN (d)
11548 && !DECL_NOT_REALLY_EXTERN (d))
11549 mark_definable (d);
11551 input_location = DECL_SOURCE_LOCATION (d);
11553 /* If D is a member of an explicitly instantiated class template,
11554 and no definition is available, treat it like an implicit
11556 if (!pattern_defined && expl_inst_class_mem_p
11557 && DECL_EXPLICIT_INSTANTIATION (d))
11559 DECL_NOT_REALLY_EXTERN (d) = 0;
11560 DECL_INTERFACE_KNOWN (d) = 0;
11561 SET_DECL_IMPLICIT_INSTANTIATION (d);
11566 /* Recheck the substitutions to obtain any warning messages
11567 about ignoring cv qualifiers. */
11568 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11569 tree type = TREE_TYPE (gen);
11571 /* Make sure that we can see identifiers, and compute access
11572 correctly. D is already the target FUNCTION_DECL with the
11574 push_access_scope (d);
11576 if (TREE_CODE (gen) == FUNCTION_DECL)
11578 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11579 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11580 tf_error | tf_warning, d);
11581 /* Don't simply tsubst the function type, as that will give
11582 duplicate warnings about poor parameter qualifications.
11583 The function arguments are the same as the decl_arguments
11584 without the top level cv qualifiers. */
11585 type = TREE_TYPE (type);
11587 tsubst (type, gen_args, tf_error | tf_warning, d);
11589 pop_access_scope (d);
11592 /* Check to see whether we know that this template will be
11593 instantiated in some other file, as with "extern template"
11595 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
11596 /* In general, we do not instantiate such templates... */
11598 /* ... but we instantiate inline functions so that we can inline
11600 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
11601 /* ... we instantiate static data members whose values are
11602 needed in integral constant expressions. */
11603 && ! (TREE_CODE (d) == VAR_DECL
11604 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
11606 /* Defer all other templates, unless we have been explicitly
11607 forbidden from doing so. */
11608 if (/* If there is no definition, we cannot instantiate the
11611 /* If it's OK to postpone instantiation, do so. */
11613 /* If this is a static data member that will be defined
11614 elsewhere, we don't want to instantiate the entire data
11615 member, but we do want to instantiate the initializer so that
11616 we can substitute that elsewhere. */
11617 || (external_p && TREE_CODE (d) == VAR_DECL))
11619 /* The definition of the static data member is now required so
11620 we must substitute the initializer. */
11621 if (TREE_CODE (d) == VAR_DECL
11622 && !DECL_INITIAL (d)
11623 && DECL_INITIAL (code_pattern))
11628 ns = decl_namespace_context (d);
11629 push_nested_namespace (ns);
11630 push_nested_class (DECL_CONTEXT (d));
11631 init = tsubst_expr (DECL_INITIAL (code_pattern),
11633 tf_error | tf_warning, NULL_TREE);
11634 DECL_INITIAL (d) = init;
11635 cp_finish_decl (d, init, /*asmspec_tree=*/NULL_TREE,
11636 LOOKUP_ONLYCONVERTING);
11637 pop_nested_class ();
11638 pop_nested_namespace (ns);
11641 /* We restore the source position here because it's used by
11642 add_pending_template. */
11643 input_location = saved_loc;
11645 if (at_eof && !pattern_defined
11646 && DECL_EXPLICIT_INSTANTIATION (d))
11649 The definition of a non-exported function template, a
11650 non-exported member function template, or a non-exported
11651 member function or static data member of a class template
11652 shall be present in every translation unit in which it is
11653 explicitly instantiated. */
11655 ("explicit instantiation of %qD but no definition available", d);
11657 /* ??? Historically, we have instantiated inline functions, even
11658 when marked as "extern template". */
11659 if (!(external_p && TREE_CODE (d) == VAR_DECL))
11660 add_pending_template (d);
11663 /* Tell the repository that D is available in this translation unit
11664 -- and see if it is supposed to be instantiated here. */
11665 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11667 /* In a PCH file, despite the fact that the repository hasn't
11668 requested instantiation in the PCH it is still possible that
11669 an instantiation will be required in a file that includes the
11672 add_pending_template (d);
11673 /* Instantiate inline functions so that the inliner can do its
11674 job, even though we'll not be emitting a copy of this
11676 if (!(TREE_CODE (d) == FUNCTION_DECL
11677 && flag_inline_trees
11678 && DECL_DECLARED_INLINE_P (d)))
11682 need_push = !cfun || !global_bindings_p ();
11684 push_to_top_level ();
11686 /* Mark D as instantiated so that recursive calls to
11687 instantiate_decl do not try to instantiate it again. */
11688 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11690 /* Regenerate the declaration in case the template has been modified
11691 by a subsequent redeclaration. */
11692 regenerate_decl_from_template (d, td);
11694 /* We already set the file and line above. Reset them now in case
11695 they changed as a result of calling regenerate_decl_from_template. */
11696 input_location = DECL_SOURCE_LOCATION (d);
11698 if (TREE_CODE (d) == VAR_DECL)
11700 /* Clear out DECL_RTL; whatever was there before may not be right
11701 since we've reset the type of the declaration. */
11702 SET_DECL_RTL (d, NULL_RTX);
11703 DECL_IN_AGGR_P (d) = 0;
11705 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11706 initializer. That function will defer actual emission until
11707 we have a chance to determine linkage. */
11708 DECL_EXTERNAL (d) = 0;
11710 /* Enter the scope of D so that access-checking works correctly. */
11711 push_nested_class (DECL_CONTEXT (d));
11712 cp_finish_decl (d, DECL_INITIAL (d), NULL_TREE, 0);
11713 pop_nested_class ();
11715 else if (TREE_CODE (d) == FUNCTION_DECL)
11717 htab_t saved_local_specializations;
11722 /* Save away the current list, in case we are instantiating one
11723 template from within the body of another. */
11724 saved_local_specializations = local_specializations;
11726 /* Set up the list of local specializations. */
11727 local_specializations = htab_create (37,
11728 hash_local_specialization,
11729 eq_local_specializations,
11732 /* Set up context. */
11733 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11735 /* Create substitution entries for the parameters. */
11736 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11737 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11738 spec_parm = DECL_ARGUMENTS (d);
11739 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11741 register_local_specialization (spec_parm, tmpl_parm);
11742 spec_parm = skip_artificial_parms_for (d, spec_parm);
11743 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11747 register_local_specialization (spec_parm, tmpl_parm);
11748 tmpl_parm = TREE_CHAIN (tmpl_parm);
11749 spec_parm = TREE_CHAIN (spec_parm);
11751 gcc_assert (!spec_parm);
11753 /* Substitute into the body of the function. */
11754 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11755 tf_error | tf_warning, tmpl);
11757 /* We don't need the local specializations any more. */
11758 htab_delete (local_specializations);
11759 local_specializations = saved_local_specializations;
11761 /* Finish the function. */
11762 d = finish_function (0);
11763 expand_or_defer_fn (d);
11766 /* We're not deferring instantiation any more. */
11767 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11770 pop_from_top_level ();
11773 input_location = saved_loc;
11774 pop_deferring_access_checks ();
11775 pop_tinst_level ();
11777 timevar_pop (TV_PARSE);
11782 /* Run through the list of templates that we wish we could
11783 instantiate, and instantiate any we can. RETRIES is the
11784 number of times we retry pending template instantiation. */
11787 instantiate_pending_templates (int retries)
11790 tree last = NULL_TREE;
11792 location_t saved_loc = input_location;
11793 int saved_in_system_header = in_system_header;
11795 /* Instantiating templates may trigger vtable generation. This in turn
11796 may require further template instantiations. We place a limit here
11797 to avoid infinite loop. */
11798 if (pending_templates && retries >= max_tinst_depth)
11800 tree decl = TREE_VALUE (pending_templates);
11802 error ("template instantiation depth exceeds maximum of %d"
11803 " instantiating %q+D, possibly from virtual table generation"
11804 " (use -ftemplate-depth-NN to increase the maximum)",
11805 max_tinst_depth, decl);
11806 if (TREE_CODE (decl) == FUNCTION_DECL)
11807 /* Pretend that we defined it. */
11808 DECL_INITIAL (decl) = error_mark_node;
11816 t = &pending_templates;
11819 tree instantiation = TREE_VALUE (*t);
11821 reopen_tinst_level (TREE_PURPOSE (*t));
11823 if (TYPE_P (instantiation))
11827 if (!COMPLETE_TYPE_P (instantiation))
11829 instantiate_class_template (instantiation);
11830 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11831 for (fn = TYPE_METHODS (instantiation);
11833 fn = TREE_CHAIN (fn))
11834 if (! DECL_ARTIFICIAL (fn))
11835 instantiate_decl (fn,
11837 /*expl_inst_class_mem_p=*/false);
11838 if (COMPLETE_TYPE_P (instantiation))
11842 if (COMPLETE_TYPE_P (instantiation))
11843 /* If INSTANTIATION has been instantiated, then we don't
11844 need to consider it again in the future. */
11845 *t = TREE_CHAIN (*t);
11849 t = &TREE_CHAIN (*t);
11854 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11855 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11858 = instantiate_decl (instantiation,
11860 /*expl_inst_class_mem_p=*/false);
11861 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11865 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11866 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11867 /* If INSTANTIATION has been instantiated, then we don't
11868 need to consider it again in the future. */
11869 *t = TREE_CHAIN (*t);
11873 t = &TREE_CHAIN (*t);
11877 current_tinst_level = NULL_TREE;
11879 last_pending_template = last;
11881 while (reconsider);
11883 input_location = saved_loc;
11884 in_system_header = saved_in_system_header;
11887 /* Substitute ARGVEC into T, which is a list of initializers for
11888 either base class or a non-static data member. The TREE_PURPOSEs
11889 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11890 instantiate_decl. */
11893 tsubst_initializer_list (tree t, tree argvec)
11895 tree inits = NULL_TREE;
11897 for (; t; t = TREE_CHAIN (t))
11902 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11904 decl = expand_member_init (decl);
11905 if (decl && !DECL_P (decl))
11906 in_base_initializer = 1;
11908 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11910 in_base_initializer = 0;
11914 init = build_tree_list (decl, init);
11915 TREE_CHAIN (init) = inits;
11922 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11925 set_current_access_from_decl (tree decl)
11927 if (TREE_PRIVATE (decl))
11928 current_access_specifier = access_private_node;
11929 else if (TREE_PROTECTED (decl))
11930 current_access_specifier = access_protected_node;
11932 current_access_specifier = access_public_node;
11935 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11936 is the instantiation (which should have been created with
11937 start_enum) and ARGS are the template arguments to use. */
11940 tsubst_enum (tree tag, tree newtag, tree args)
11944 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11949 decl = TREE_VALUE (e);
11950 /* Note that in a template enum, the TREE_VALUE is the
11951 CONST_DECL, not the corresponding INTEGER_CST. */
11952 value = tsubst_expr (DECL_INITIAL (decl),
11953 args, tf_error | tf_warning,
11956 /* Give this enumeration constant the correct access. */
11957 set_current_access_from_decl (decl);
11959 /* Actually build the enumerator itself. */
11960 build_enumerator (DECL_NAME (decl), value, newtag);
11963 finish_enum (newtag);
11964 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11965 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11968 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11969 its type -- but without substituting the innermost set of template
11970 arguments. So, innermost set of template parameters will appear in
11974 get_mostly_instantiated_function_type (tree decl)
11982 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11983 targs = DECL_TI_ARGS (decl);
11984 tparms = DECL_TEMPLATE_PARMS (tmpl);
11985 parm_depth = TMPL_PARMS_DEPTH (tparms);
11987 /* There should be as many levels of arguments as there are levels
11989 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11991 fn_type = TREE_TYPE (tmpl);
11993 if (parm_depth == 1)
11994 /* No substitution is necessary. */
11998 int i, save_access_control;
12001 /* Replace the innermost level of the TARGS with NULL_TREEs to
12002 let tsubst know not to substitute for those parameters. */
12003 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
12004 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
12005 SET_TMPL_ARGS_LEVEL (partial_args, i,
12006 TMPL_ARGS_LEVEL (targs, i));
12007 SET_TMPL_ARGS_LEVEL (partial_args,
12008 TMPL_ARGS_DEPTH (targs),
12009 make_tree_vec (DECL_NTPARMS (tmpl)));
12011 /* Disable access control as this function is used only during
12013 save_access_control = flag_access_control;
12014 flag_access_control = 0;
12016 ++processing_template_decl;
12017 /* Now, do the (partial) substitution to figure out the
12018 appropriate function type. */
12019 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
12020 --processing_template_decl;
12022 /* Substitute into the template parameters to obtain the real
12023 innermost set of parameters. This step is important if the
12024 innermost set of template parameters contains value
12025 parameters whose types depend on outer template parameters. */
12026 TREE_VEC_LENGTH (partial_args)--;
12027 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
12029 flag_access_control = save_access_control;
12035 /* Return truthvalue if we're processing a template different from
12036 the last one involved in diagnostics. */
12038 problematic_instantiation_changed (void)
12040 return last_template_error_tick != tinst_level_tick;
12043 /* Remember current template involved in diagnostics. */
12045 record_last_problematic_instantiation (void)
12047 last_template_error_tick = tinst_level_tick;
12051 current_instantiation (void)
12053 return current_tinst_level;
12056 /* [temp.param] Check that template non-type parm TYPE is of an allowable
12057 type. Return zero for ok, nonzero for disallowed. Issue error and
12058 warning messages under control of COMPLAIN. */
12061 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
12063 if (INTEGRAL_TYPE_P (type))
12065 else if (POINTER_TYPE_P (type))
12067 else if (TYPE_PTR_TO_MEMBER_P (type))
12069 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
12071 else if (TREE_CODE (type) == TYPENAME_TYPE)
12074 if (complain & tf_error)
12075 error ("%q#T is not a valid type for a template constant parameter", type);
12079 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
12080 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
12083 dependent_type_p_r (tree type)
12089 A type is dependent if it is:
12091 -- a template parameter. Template template parameters are types
12092 for us (since TYPE_P holds true for them) so we handle
12094 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
12095 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
12097 /* -- a qualified-id with a nested-name-specifier which contains a
12098 class-name that names a dependent type or whose unqualified-id
12099 names a dependent type. */
12100 if (TREE_CODE (type) == TYPENAME_TYPE)
12102 /* -- a cv-qualified type where the cv-unqualified type is
12104 type = TYPE_MAIN_VARIANT (type);
12105 /* -- a compound type constructed from any dependent type. */
12106 if (TYPE_PTR_TO_MEMBER_P (type))
12107 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
12108 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
12110 else if (TREE_CODE (type) == POINTER_TYPE
12111 || TREE_CODE (type) == REFERENCE_TYPE)
12112 return dependent_type_p (TREE_TYPE (type));
12113 else if (TREE_CODE (type) == FUNCTION_TYPE
12114 || TREE_CODE (type) == METHOD_TYPE)
12118 if (dependent_type_p (TREE_TYPE (type)))
12120 for (arg_type = TYPE_ARG_TYPES (type);
12122 arg_type = TREE_CHAIN (arg_type))
12123 if (dependent_type_p (TREE_VALUE (arg_type)))
12127 /* -- an array type constructed from any dependent type or whose
12128 size is specified by a constant expression that is
12129 value-dependent. */
12130 if (TREE_CODE (type) == ARRAY_TYPE)
12132 if (TYPE_DOMAIN (type)
12133 && ((value_dependent_expression_p
12134 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
12135 || (type_dependent_expression_p
12136 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
12138 return dependent_type_p (TREE_TYPE (type));
12141 /* -- a template-id in which either the template name is a template
12143 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
12145 /* ... or any of the template arguments is a dependent type or
12146 an expression that is type-dependent or value-dependent. */
12147 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
12148 && (any_dependent_template_arguments_p
12149 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
12152 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
12153 expression is not type-dependent, then it should already been
12155 if (TREE_CODE (type) == TYPEOF_TYPE)
12158 /* The standard does not specifically mention types that are local
12159 to template functions or local classes, but they should be
12160 considered dependent too. For example:
12162 template <int I> void f() {
12167 The size of `E' cannot be known until the value of `I' has been
12168 determined. Therefore, `E' must be considered dependent. */
12169 scope = TYPE_CONTEXT (type);
12170 if (scope && TYPE_P (scope))
12171 return dependent_type_p (scope);
12172 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12173 return type_dependent_expression_p (scope);
12175 /* Other types are non-dependent. */
12179 /* Returns TRUE if TYPE is dependent, in the sense of
12180 [temp.dep.type]. */
12183 dependent_type_p (tree type)
12185 /* If there are no template parameters in scope, then there can't be
12186 any dependent types. */
12187 if (!processing_template_decl)
12190 /* If the type is NULL, we have not computed a type for the entity
12191 in question; in that case, the type is dependent. */
12195 /* Erroneous types can be considered non-dependent. */
12196 if (type == error_mark_node)
12199 /* If we have not already computed the appropriate value for TYPE,
12201 if (!TYPE_DEPENDENT_P_VALID (type))
12203 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12204 TYPE_DEPENDENT_P_VALID (type) = 1;
12207 return TYPE_DEPENDENT_P (type);
12210 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12213 dependent_scope_ref_p (tree expression, bool criterion (tree))
12218 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12220 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12223 scope = TREE_OPERAND (expression, 0);
12224 name = TREE_OPERAND (expression, 1);
12228 An id-expression is type-dependent if it contains a
12229 nested-name-specifier that contains a class-name that names a
12231 /* The suggested resolution to Core Issue 2 implies that if the
12232 qualifying type is the current class, then we must peek
12235 && currently_open_class (scope)
12236 && !criterion (name))
12238 if (dependent_type_p (scope))
12244 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12245 [temp.dep.constexpr] */
12248 value_dependent_expression_p (tree expression)
12250 if (!processing_template_decl)
12253 /* A name declared with a dependent type. */
12254 if (DECL_P (expression) && type_dependent_expression_p (expression))
12257 switch (TREE_CODE (expression))
12259 case IDENTIFIER_NODE:
12260 /* A name that has not been looked up -- must be dependent. */
12263 case TEMPLATE_PARM_INDEX:
12264 /* A non-type template parm. */
12268 /* A non-type template parm. */
12269 if (DECL_TEMPLATE_PARM_P (expression))
12274 /* A constant with integral or enumeration type and is initialized
12275 with an expression that is value-dependent. */
12276 if (DECL_INITIAL (expression)
12277 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12278 && value_dependent_expression_p (DECL_INITIAL (expression)))
12282 case DYNAMIC_CAST_EXPR:
12283 case STATIC_CAST_EXPR:
12284 case CONST_CAST_EXPR:
12285 case REINTERPRET_CAST_EXPR:
12287 /* These expressions are value-dependent if the type to which
12288 the cast occurs is dependent or the expression being casted
12289 is value-dependent. */
12291 tree type = TREE_TYPE (expression);
12293 if (dependent_type_p (type))
12296 /* A functional cast has a list of operands. */
12297 expression = TREE_OPERAND (expression, 0);
12300 /* If there are no operands, it must be an expression such
12301 as "int()". This should not happen for aggregate types
12302 because it would form non-constant expressions. */
12303 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12308 if (TREE_CODE (expression) == TREE_LIST)
12310 for (; expression; expression = TREE_CHAIN (expression))
12311 if (value_dependent_expression_p (TREE_VALUE (expression)))
12316 return value_dependent_expression_p (expression);
12321 /* A `sizeof' expression is value-dependent if the operand is
12323 expression = TREE_OPERAND (expression, 0);
12324 if (TYPE_P (expression))
12325 return dependent_type_p (expression);
12326 return type_dependent_expression_p (expression);
12329 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12331 case COMPONENT_REF:
12332 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12333 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12336 /* A CALL_EXPR is value-dependent if any argument is
12337 value-dependent. Why do we have to handle CALL_EXPRs in this
12338 function at all? First, some function calls, those for which
12339 value_dependent_expression_p is true, man appear in constant
12340 expressions. Second, there appear to be bugs which result in
12341 other CALL_EXPRs reaching this point. */
12343 tree function = TREE_OPERAND (expression, 0);
12344 tree args = TREE_OPERAND (expression, 1);
12346 if (value_dependent_expression_p (function))
12352 if (TREE_CODE (args) == TREE_LIST)
12354 for (; args; args = TREE_CHAIN (args))
12355 if (value_dependent_expression_p (TREE_VALUE (args)))
12360 return value_dependent_expression_p (args);
12364 /* A constant expression is value-dependent if any subexpression is
12365 value-dependent. */
12366 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12368 case tcc_reference:
12370 return (value_dependent_expression_p
12371 (TREE_OPERAND (expression, 0)));
12373 case tcc_comparison:
12375 return ((value_dependent_expression_p
12376 (TREE_OPERAND (expression, 0)))
12377 || (value_dependent_expression_p
12378 (TREE_OPERAND (expression, 1))));
12380 case tcc_expression:
12383 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12384 /* In some cases, some of the operands may be missing.
12385 (For example, in the case of PREDECREMENT_EXPR, the
12386 amount to increment by may be missing.) That doesn't
12387 make the expression dependent. */
12388 if (TREE_OPERAND (expression, i)
12389 && (value_dependent_expression_p
12390 (TREE_OPERAND (expression, i))))
12400 /* The expression is not value-dependent. */
12404 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12405 [temp.dep.expr]. */
12408 type_dependent_expression_p (tree expression)
12410 if (!processing_template_decl)
12413 if (expression == error_mark_node)
12416 /* An unresolved name is always dependent. */
12417 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12420 /* Some expression forms are never type-dependent. */
12421 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12422 || TREE_CODE (expression) == SIZEOF_EXPR
12423 || TREE_CODE (expression) == ALIGNOF_EXPR
12424 || TREE_CODE (expression) == TYPEID_EXPR
12425 || TREE_CODE (expression) == DELETE_EXPR
12426 || TREE_CODE (expression) == VEC_DELETE_EXPR
12427 || TREE_CODE (expression) == THROW_EXPR)
12430 /* The types of these expressions depends only on the type to which
12431 the cast occurs. */
12432 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12433 || TREE_CODE (expression) == STATIC_CAST_EXPR
12434 || TREE_CODE (expression) == CONST_CAST_EXPR
12435 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12436 || TREE_CODE (expression) == CAST_EXPR)
12437 return dependent_type_p (TREE_TYPE (expression));
12439 /* The types of these expressions depends only on the type created
12440 by the expression. */
12441 if (TREE_CODE (expression) == NEW_EXPR
12442 || TREE_CODE (expression) == VEC_NEW_EXPR)
12444 /* For NEW_EXPR tree nodes created inside a template, either
12445 the object type itself or a TREE_LIST may appear as the
12447 tree type = TREE_OPERAND (expression, 1);
12448 if (TREE_CODE (type) == TREE_LIST)
12449 /* This is an array type. We need to check array dimensions
12451 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12452 || value_dependent_expression_p
12453 (TREE_OPERAND (TREE_VALUE (type), 1));
12455 return dependent_type_p (type);
12458 if (TREE_CODE (expression) == SCOPE_REF
12459 && dependent_scope_ref_p (expression,
12460 type_dependent_expression_p))
12463 if (TREE_CODE (expression) == FUNCTION_DECL
12464 && DECL_LANG_SPECIFIC (expression)
12465 && DECL_TEMPLATE_INFO (expression)
12466 && (any_dependent_template_arguments_p
12467 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12470 if (TREE_CODE (expression) == TEMPLATE_DECL
12471 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12474 if (TREE_TYPE (expression) == unknown_type_node)
12476 if (TREE_CODE (expression) == ADDR_EXPR)
12477 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12478 if (TREE_CODE (expression) == COMPONENT_REF
12479 || TREE_CODE (expression) == OFFSET_REF)
12481 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12483 expression = TREE_OPERAND (expression, 1);
12484 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12487 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12488 if (TREE_CODE (expression) == SCOPE_REF)
12491 if (TREE_CODE (expression) == BASELINK)
12492 expression = BASELINK_FUNCTIONS (expression);
12494 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12496 if (any_dependent_template_arguments_p
12497 (TREE_OPERAND (expression, 1)))
12499 expression = TREE_OPERAND (expression, 0);
12501 gcc_assert (TREE_CODE (expression) == OVERLOAD
12502 || TREE_CODE (expression) == FUNCTION_DECL);
12506 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12508 expression = OVL_NEXT (expression);
12513 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
12515 return (dependent_type_p (TREE_TYPE (expression)));
12518 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12519 contains a type-dependent expression. */
12522 any_type_dependent_arguments_p (tree args)
12526 tree arg = TREE_VALUE (args);
12528 if (type_dependent_expression_p (arg))
12530 args = TREE_CHAIN (args);
12535 /* Returns TRUE if the ARG (a template argument) is dependent. */
12538 dependent_template_arg_p (tree arg)
12540 if (!processing_template_decl)
12543 if (TREE_CODE (arg) == TEMPLATE_DECL
12544 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12545 return dependent_template_p (arg);
12546 else if (TYPE_P (arg))
12547 return dependent_type_p (arg);
12549 return (type_dependent_expression_p (arg)
12550 || value_dependent_expression_p (arg));
12553 /* Returns true if ARGS (a collection of template arguments) contains
12554 any dependent arguments. */
12557 any_dependent_template_arguments_p (tree args)
12565 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12567 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12568 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12569 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12576 /* Returns TRUE if the template TMPL is dependent. */
12579 dependent_template_p (tree tmpl)
12581 if (TREE_CODE (tmpl) == OVERLOAD)
12585 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12587 tmpl = OVL_CHAIN (tmpl);
12592 /* Template template parameters are dependent. */
12593 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12594 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12596 /* So are names that have not been looked up. */
12597 if (TREE_CODE (tmpl) == SCOPE_REF
12598 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12600 /* So are member templates of dependent classes. */
12601 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12602 return dependent_type_p (DECL_CONTEXT (tmpl));
12606 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12609 dependent_template_id_p (tree tmpl, tree args)
12611 return (dependent_template_p (tmpl)
12612 || any_dependent_template_arguments_p (args));
12615 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12616 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12617 can be found. Note that this function peers inside uninstantiated
12618 templates and therefore should be used only in extremely limited
12619 situations. ONLY_CURRENT_P restricts this peering to the currently
12620 open classes hierarchy (which is required when comparing types). */
12623 resolve_typename_type (tree type, bool only_current_p)
12631 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12633 scope = TYPE_CONTEXT (type);
12634 name = TYPE_IDENTIFIER (type);
12636 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12637 it first before we can figure out what NAME refers to. */
12638 if (TREE_CODE (scope) == TYPENAME_TYPE)
12639 scope = resolve_typename_type (scope, only_current_p);
12640 /* If we don't know what SCOPE refers to, then we cannot resolve the
12642 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12643 return error_mark_node;
12644 /* If the SCOPE is a template type parameter, we have no way of
12645 resolving the name. */
12646 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12648 /* If the SCOPE is not the current instantiation, there's no reason
12649 to look inside it. */
12650 if (only_current_p && !currently_open_class (scope))
12651 return error_mark_node;
12652 /* If SCOPE is a partial instantiation, it will not have a valid
12653 TYPE_FIELDS list, so use the original template. */
12654 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12655 /* Enter the SCOPE so that name lookup will be resolved as if we
12656 were in the class definition. In particular, SCOPE will no
12657 longer be considered a dependent type. */
12658 pushed_scope = push_scope (scope);
12659 /* Look up the declaration. */
12660 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12661 /* Obtain the set of qualifiers applied to the TYPE. */
12662 quals = cp_type_quals (type);
12663 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12664 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12666 type = error_mark_node;
12667 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12668 && TREE_CODE (decl) == TYPE_DECL)
12669 type = TREE_TYPE (decl);
12670 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12671 && DECL_CLASS_TEMPLATE_P (decl))
12675 /* Obtain the template and the arguments. */
12676 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12677 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12678 /* Instantiate the template. */
12679 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12680 /*entering_scope=*/0, tf_error | tf_user);
12683 type = error_mark_node;
12684 /* Qualify the resulting type. */
12685 if (type != error_mark_node && quals)
12686 type = cp_build_qualified_type (type, quals);
12687 /* Leave the SCOPE. */
12689 pop_scope (pushed_scope);
12694 /* EXPR is an expression which is not type-dependent. Return a proxy
12695 for EXPR that can be used to compute the types of larger
12696 expressions containing EXPR. */
12699 build_non_dependent_expr (tree expr)
12703 /* Preserve null pointer constants so that the type of things like
12704 "p == 0" where "p" is a pointer can be determined. */
12705 if (null_ptr_cst_p (expr))
12707 /* Preserve OVERLOADs; the functions must be available to resolve
12709 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12710 TREE_OPERAND (expr, 0) :
12711 TREE_CODE (expr) == COMPONENT_REF ?
12712 TREE_OPERAND (expr, 1) : expr);
12713 if (is_overloaded_fn (inner_expr)
12714 || TREE_CODE (inner_expr) == OFFSET_REF)
12716 /* There is no need to return a proxy for a variable. */
12717 if (TREE_CODE (expr) == VAR_DECL)
12719 /* Preserve string constants; conversions from string constants to
12720 "char *" are allowed, even though normally a "const char *"
12721 cannot be used to initialize a "char *". */
12722 if (TREE_CODE (expr) == STRING_CST)
12724 /* Preserve arithmetic constants, as an optimization -- there is no
12725 reason to create a new node. */
12726 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12728 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12729 There is at least one place where we want to know that a
12730 particular expression is a throw-expression: when checking a ?:
12731 expression, there are special rules if the second or third
12732 argument is a throw-expression. */
12733 if (TREE_CODE (expr) == THROW_EXPR)
12736 if (TREE_CODE (expr) == COND_EXPR)
12737 return build3 (COND_EXPR,
12739 TREE_OPERAND (expr, 0),
12740 (TREE_OPERAND (expr, 1)
12741 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12742 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12743 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12744 if (TREE_CODE (expr) == COMPOUND_EXPR
12745 && !COMPOUND_EXPR_OVERLOADED (expr))
12746 return build2 (COMPOUND_EXPR,
12748 TREE_OPERAND (expr, 0),
12749 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12751 /* If the type is unknown, it can't really be non-dependent */
12752 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
12754 /* Otherwise, build a NON_DEPENDENT_EXPR.
12756 REFERENCE_TYPEs are not stripped for expressions in templates
12757 because doing so would play havoc with mangling. Consider, for
12760 template <typename T> void f<T& g>() { g(); }
12762 In the body of "f", the expression for "g" will have
12763 REFERENCE_TYPE, even though the standard says that it should
12764 not. The reason is that we must preserve the syntactic form of
12765 the expression so that mangling (say) "f<g>" inside the body of
12766 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12768 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12771 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12772 Return a new TREE_LIST with the various arguments replaced with
12773 equivalent non-dependent expressions. */
12776 build_non_dependent_args (tree args)
12781 new_args = NULL_TREE;
12782 for (a = args; a; a = TREE_CHAIN (a))
12783 new_args = tree_cons (NULL_TREE,
12784 build_non_dependent_expr (TREE_VALUE (a)),
12786 return nreverse (new_args);
12789 #include "gt-cp-pt.h"