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 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, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, 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"
38 #include "tree-inline.h"
45 #include "tree-iterator.h"
47 /* The type of functions taking a tree, and some additional data, and
49 typedef int (*tree_fn_t) (tree, void*);
51 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
52 instantiations have been deferred, either because their definitions
53 were not yet available, or because we were putting off doing the work.
54 The TREE_PURPOSE of each entry is either a DECL (for a function or
55 static data member), or a TYPE (for a class) indicating what we are
56 hoping to instantiate. The TREE_VALUE is not used. */
57 static GTY(()) tree pending_templates;
58 static GTY(()) tree last_pending_template;
60 int processing_template_parmlist;
61 static int template_header_count;
63 static GTY(()) tree saved_trees;
64 static GTY(()) varray_type inline_parm_levels;
65 static size_t inline_parm_levels_used;
67 static GTY(()) tree current_tinst_level;
69 static GTY(()) tree saved_access_scope;
71 /* Live only within one (recursive) call to tsubst_expr. We use
72 this to pass the statement expression node from the STMT_EXPR
73 to the EXPR_STMT that is its result. */
74 static tree cur_stmt_expr;
76 /* A map from local variable declarations in the body of the template
77 presently being instantiated to the corresponding instantiated
79 static htab_t local_specializations;
81 #define UNIFY_ALLOW_NONE 0
82 #define UNIFY_ALLOW_MORE_CV_QUAL 1
83 #define UNIFY_ALLOW_LESS_CV_QUAL 2
84 #define UNIFY_ALLOW_DERIVED 4
85 #define UNIFY_ALLOW_INTEGER 8
86 #define UNIFY_ALLOW_OUTER_LEVEL 16
87 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
88 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
89 #define UNIFY_ALLOW_MAX_CORRECTION 128
91 static void push_access_scope (tree);
92 static void pop_access_scope (tree);
93 static int resolve_overloaded_unification (tree, tree, tree, tree,
94 unification_kind_t, int);
95 static int try_one_overload (tree, tree, tree, tree, tree,
96 unification_kind_t, int, bool);
97 static int unify (tree, tree, tree, tree, int);
98 static void add_pending_template (tree);
99 static void reopen_tinst_level (tree);
100 static tree classtype_mangled_name (tree);
101 static char* mangle_class_name_for_template (const char *, tree, tree);
102 static tree tsubst_initializer_list (tree, tree);
103 static tree get_class_bindings (tree, tree, tree);
104 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
105 static void tsubst_enum (tree, tree, tree);
106 static tree add_to_template_args (tree, tree);
107 static tree add_outermost_template_args (tree, tree);
108 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
109 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
110 static int type_unification_real (tree, tree, tree, tree,
111 int, unification_kind_t, int, int);
112 static void note_template_header (int);
113 static tree convert_nontype_argument_function (tree, tree);
114 static tree convert_nontype_argument (tree, tree);
115 static tree convert_template_argument (tree, tree, tree,
116 tsubst_flags_t, int, tree);
117 static tree get_bindings_overload (tree, tree, 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);
132 static tree get_bindings_real (tree, tree, tree, int, int, int);
133 static int template_decl_level (tree);
134 static int check_cv_quals_for_unify (int, tree, tree);
135 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
136 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
137 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
138 static void regenerate_decl_from_template (tree, tree);
139 static tree most_specialized (tree, tree, tree);
140 static tree most_specialized_class (tree, tree);
141 static int template_class_depth_real (tree, int);
142 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
143 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
144 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
145 static void check_specialization_scope (void);
146 static tree process_partial_specialization (tree);
147 static void set_current_access_from_decl (tree);
148 static void check_default_tmpl_args (tree, tree, int, int);
149 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
150 static tree get_template_base (tree, tree, tree, tree);
151 static int verify_class_unification (tree, tree, tree);
152 static tree try_class_unification (tree, tree, tree, tree);
153 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
155 static tree determine_specialization (tree, tree, tree *, int, int);
156 static int template_args_equal (tree, tree);
157 static void tsubst_default_arguments (tree);
158 static tree for_each_template_parm_r (tree *, int *, void *);
159 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
160 static void copy_default_args_to_explicit_spec (tree);
161 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
162 static int eq_local_specializations (const void *, const void *);
163 static bool dependent_type_p_r (tree);
164 static tree tsubst (tree, tree, tsubst_flags_t, tree);
165 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
166 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
168 /* Make the current scope suitable for access checking when we are
169 processing T. T can be FUNCTION_DECL for instantiated function
170 template, or VAR_DECL for static member variable (need by
171 instantiate_decl). */
174 push_access_scope (tree t)
176 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
177 || TREE_CODE (t) == VAR_DECL);
179 if (DECL_CLASS_SCOPE_P (t))
180 push_nested_class (DECL_CONTEXT (t));
182 push_to_top_level ();
184 if (TREE_CODE (t) == FUNCTION_DECL)
186 saved_access_scope = tree_cons
187 (NULL_TREE, current_function_decl, saved_access_scope);
188 current_function_decl = t;
192 /* Restore the scope set up by push_access_scope. T is the node we
196 pop_access_scope (tree t)
198 if (TREE_CODE (t) == FUNCTION_DECL)
200 current_function_decl = TREE_VALUE (saved_access_scope);
201 saved_access_scope = TREE_CHAIN (saved_access_scope);
204 if (DECL_CLASS_SCOPE_P (t))
207 pop_from_top_level ();
210 /* Do any processing required when DECL (a member template
211 declaration) is finished. Returns the TEMPLATE_DECL corresponding
212 to DECL, unless it is a specialization, in which case the DECL
213 itself is returned. */
216 finish_member_template_decl (tree decl)
218 if (decl == error_mark_node)
219 return error_mark_node;
221 gcc_assert (DECL_P (decl));
223 if (TREE_CODE (decl) == TYPE_DECL)
227 type = TREE_TYPE (decl);
228 if (IS_AGGR_TYPE (type)
229 && CLASSTYPE_TEMPLATE_INFO (type)
230 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
232 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
233 check_member_template (tmpl);
238 else if (TREE_CODE (decl) == FIELD_DECL)
239 error ("data member %qD cannot be a member template", decl);
240 else if (DECL_TEMPLATE_INFO (decl))
242 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
244 check_member_template (DECL_TI_TEMPLATE (decl));
245 return DECL_TI_TEMPLATE (decl);
251 error ("invalid member template declaration %qD", decl);
253 return error_mark_node;
256 /* Returns the template nesting level of the indicated class TYPE.
266 A<T>::B<U> has depth two, while A<T> has depth one.
267 Both A<T>::B<int> and A<int>::B<U> have depth one, if
268 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
271 This function is guaranteed to return 0 if passed NULL_TREE so
272 that, for example, `template_class_depth (current_class_type)' is
276 template_class_depth_real (tree type, int count_specializations)
281 type && TREE_CODE (type) != NAMESPACE_DECL;
282 type = (TREE_CODE (type) == FUNCTION_DECL)
283 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
285 if (TREE_CODE (type) != FUNCTION_DECL)
287 if (CLASSTYPE_TEMPLATE_INFO (type)
288 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
289 && ((count_specializations
290 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
291 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
296 if (DECL_TEMPLATE_INFO (type)
297 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
298 && ((count_specializations
299 && DECL_TEMPLATE_SPECIALIZATION (type))
300 || uses_template_parms (DECL_TI_ARGS (type))))
308 /* Returns the template nesting level of the indicated class TYPE.
309 Like template_class_depth_real, but instantiations do not count in
313 template_class_depth (tree type)
315 return template_class_depth_real (type, /*count_specializations=*/0);
318 /* Returns 1 if processing DECL as part of do_pending_inlines
319 needs us to push template parms. */
322 inline_needs_template_parms (tree decl)
324 if (! DECL_TEMPLATE_INFO (decl))
327 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
328 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
331 /* Subroutine of maybe_begin_member_template_processing.
332 Push the template parms in PARMS, starting from LEVELS steps into the
333 chain, and ending at the beginning, since template parms are listed
337 push_inline_template_parms_recursive (tree parmlist, int levels)
339 tree parms = TREE_VALUE (parmlist);
343 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
345 ++processing_template_decl;
346 current_template_parms
347 = tree_cons (size_int (processing_template_decl),
348 parms, current_template_parms);
349 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
351 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
353 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
355 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
356 gcc_assert (DECL_P (parm));
358 switch (TREE_CODE (parm))
367 /* Make a CONST_DECL as is done in process_template_parm.
368 It is ugly that we recreate this here; the original
369 version built in process_template_parm is no longer
371 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
373 DECL_ARTIFICIAL (decl) = 1;
374 TREE_CONSTANT (decl) = 1;
375 TREE_INVARIANT (decl) = 1;
376 TREE_READONLY (decl) = 1;
377 DECL_INITIAL (decl) = DECL_INITIAL (parm);
378 SET_DECL_TEMPLATE_PARM_P (decl);
389 /* Restore the template parameter context for a member template or
390 a friend template defined in a class definition. */
393 maybe_begin_member_template_processing (tree decl)
398 if (inline_needs_template_parms (decl))
400 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
401 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
403 if (DECL_TEMPLATE_SPECIALIZATION (decl))
406 parms = TREE_CHAIN (parms);
409 push_inline_template_parms_recursive (parms, levels);
412 /* Remember how many levels of template parameters we pushed so that
413 we can pop them later. */
414 if (!inline_parm_levels)
415 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
416 if (inline_parm_levels_used == inline_parm_levels->num_elements)
417 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
418 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
419 ++inline_parm_levels_used;
422 /* Undo the effects of begin_member_template_processing. */
425 maybe_end_member_template_processing (void)
429 if (!inline_parm_levels_used)
432 --inline_parm_levels_used;
434 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
437 --processing_template_decl;
438 current_template_parms = TREE_CHAIN (current_template_parms);
443 /* Return a new template argument vector which contains all of ARGS,
444 but has as its innermost set of arguments the EXTRA_ARGS. */
447 add_to_template_args (tree args, tree extra_args)
454 extra_depth = TMPL_ARGS_DEPTH (extra_args);
455 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
457 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
458 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
460 for (j = 1; j <= extra_depth; ++j, ++i)
461 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
466 /* Like add_to_template_args, but only the outermost ARGS are added to
467 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
468 (EXTRA_ARGS) levels are added. This function is used to combine
469 the template arguments from a partial instantiation with the
470 template arguments used to attain the full instantiation from the
471 partial instantiation. */
474 add_outermost_template_args (tree args, tree extra_args)
478 /* If there are more levels of EXTRA_ARGS than there are ARGS,
479 something very fishy is going on. */
480 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
482 /* If *all* the new arguments will be the EXTRA_ARGS, just return
484 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
487 /* For the moment, we make ARGS look like it contains fewer levels. */
488 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
490 new_args = add_to_template_args (args, extra_args);
492 /* Now, we restore ARGS to its full dimensions. */
493 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
498 /* Return the N levels of innermost template arguments from the ARGS. */
501 get_innermost_template_args (tree args, int n)
509 /* If N is 1, just return the innermost set of template arguments. */
511 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
513 /* If we're not removing anything, just return the arguments we were
515 extra_levels = TMPL_ARGS_DEPTH (args) - n;
516 gcc_assert (extra_levels >= 0);
517 if (extra_levels == 0)
520 /* Make a new set of arguments, not containing the outer arguments. */
521 new_args = make_tree_vec (n);
522 for (i = 1; i <= n; ++i)
523 SET_TMPL_ARGS_LEVEL (new_args, i,
524 TMPL_ARGS_LEVEL (args, i + extra_levels));
529 /* We've got a template header coming up; push to a new level for storing
533 begin_template_parm_list (void)
535 /* We use a non-tag-transparent scope here, which causes pushtag to
536 put tags in this scope, rather than in the enclosing class or
537 namespace scope. This is the right thing, since we want
538 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
539 global template class, push_template_decl handles putting the
540 TEMPLATE_DECL into top-level scope. For a nested template class,
543 template <class T> struct S1 {
544 template <class T> struct S2 {};
547 pushtag contains special code to call pushdecl_with_scope on the
548 TEMPLATE_DECL for S2. */
549 begin_scope (sk_template_parms, NULL);
550 ++processing_template_decl;
551 ++processing_template_parmlist;
552 note_template_header (0);
555 /* This routine is called when a specialization is declared. If it is
556 invalid to declare a specialization here, an error is reported. */
559 check_specialization_scope (void)
561 tree scope = current_scope ();
565 An explicit specialization shall be declared in the namespace of
566 which the template is a member, or, for member templates, in the
567 namespace of which the enclosing class or enclosing class
568 template is a member. An explicit specialization of a member
569 function, member class or static data member of a class template
570 shall be declared in the namespace of which the class template
572 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
573 error ("explicit specialization in non-namespace scope %qD", scope);
577 In an explicit specialization declaration for a member of a class
578 template or a member template that appears in namespace scope,
579 the member template and some of its enclosing class templates may
580 remain unspecialized, except that the declaration shall not
581 explicitly specialize a class member template if its enclosing
582 class templates are not explicitly specialized as well. */
583 if (current_template_parms)
584 error ("enclosing class templates are not explicitly specialized");
587 /* We've just seen template <>. */
590 begin_specialization (void)
592 begin_scope (sk_template_spec, NULL);
593 note_template_header (1);
594 check_specialization_scope ();
597 /* Called at then end of processing a declaration preceded by
601 end_specialization (void)
604 reset_specialization ();
607 /* Any template <>'s that we have seen thus far are not referring to a
608 function specialization. */
611 reset_specialization (void)
613 processing_specialization = 0;
614 template_header_count = 0;
617 /* We've just seen a template header. If SPECIALIZATION is nonzero,
618 it was of the form template <>. */
621 note_template_header (int specialization)
623 processing_specialization = specialization;
624 template_header_count++;
627 /* We're beginning an explicit instantiation. */
630 begin_explicit_instantiation (void)
632 gcc_assert (!processing_explicit_instantiation);
633 processing_explicit_instantiation = true;
638 end_explicit_instantiation (void)
640 gcc_assert (processing_explicit_instantiation);
641 processing_explicit_instantiation = false;
644 /* A explicit specialization or partial specialization TMPL is being
645 declared. Check that the namespace in which the specialization is
646 occurring is permissible. Returns false iff it is invalid to
647 specialize TMPL in the current namespace. */
650 check_specialization_namespace (tree tmpl)
652 tree tpl_ns = decl_namespace_context (tmpl);
656 An explicit specialization shall be declared in the namespace of
657 which the template is a member, or, for member templates, in the
658 namespace of which the enclosing class or enclosing class
659 template is a member. An explicit specialization of a member
660 function, member class or static data member of a class template
661 shall be declared in the namespace of which the class template is
663 if (is_associated_namespace (current_namespace, tpl_ns))
664 /* Same or super-using namespace. */
668 pedwarn ("specialization of %qD in different namespace", tmpl);
669 cp_pedwarn_at (" from definition of %q#D", tmpl);
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)
680 /* TYPE maybe an ERROR_MARK_NODE. */
681 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
683 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
685 /* This is for ordinary explicit specialization and partial
686 specialization of a template class such as:
688 template <> class C<int>;
692 template <class T> class C<T*>;
694 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
696 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
697 && !COMPLETE_TYPE_P (type))
699 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
700 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
701 if (processing_template_decl)
702 push_template_decl (TYPE_MAIN_DECL (type));
704 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
705 error ("specialization of %qT after instantiation", type);
707 else if (CLASS_TYPE_P (type)
708 && !CLASSTYPE_USE_TEMPLATE (type)
709 && CLASSTYPE_TEMPLATE_INFO (type)
710 && context && CLASS_TYPE_P (context)
711 && CLASSTYPE_TEMPLATE_INFO (context))
713 /* This is for an explicit specialization of member class
714 template according to [temp.expl.spec/18]:
716 template <> template <class U> class C<int>::D;
718 The context `C<int>' must be an implicit instantiation.
719 Otherwise this is just a member class template declared
722 template <> class C<int> { template <class U> class D; };
723 template <> template <class U> class C<int>::D;
725 In the first case, `C<int>::D' is a specialization of `C<T>::D'
726 while in the second case, `C<int>::D' is a primary template
727 and `C<T>::D' may not exist. */
729 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
730 && !COMPLETE_TYPE_P (type))
734 if (current_namespace
735 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
737 pedwarn ("specializing %q#T in different namespace", type);
738 cp_pedwarn_at (" from definition of %q#D",
739 CLASSTYPE_TI_TEMPLATE (type));
742 /* Check for invalid specialization after instantiation:
744 template <> template <> class C<int>::D<int>;
745 template <> template <class U> class C<int>::D; */
747 for (t = DECL_TEMPLATE_INSTANTIATIONS
748 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
749 t; t = TREE_CHAIN (t))
750 if (TREE_VALUE (t) != type
751 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
752 error ("specialization %qT after instantiation %qT",
753 type, TREE_VALUE (t));
755 /* Mark TYPE as a specialization. And as a result, we only
756 have one level of template argument for the innermost
758 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
759 CLASSTYPE_TI_ARGS (type)
760 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
763 else if (processing_specialization)
764 error ("explicit specialization of non-template %qT", type);
767 /* Returns nonzero if we can optimize the retrieval of specializations
768 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
769 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
772 optimize_specialization_lookup_p (tree tmpl)
774 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
775 && DECL_CLASS_SCOPE_P (tmpl)
776 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
778 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
779 /* The optimized lookup depends on the fact that the
780 template arguments for the member function template apply
781 purely to the containing class, which is not true if the
782 containing class is an explicit or partial
784 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
785 && !DECL_MEMBER_TEMPLATE_P (tmpl)
786 && !DECL_CONV_FN_P (tmpl)
787 /* It is possible to have a template that is not a member
788 template and is not a member of a template class:
790 template <typename T>
791 struct S { friend A::f(); };
793 Here, the friend function is a template, but the context does
794 not have template information. The optimized lookup relies
795 on having ARGS be the template arguments for both the class
796 and the function template. */
797 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
800 /* Retrieve the specialization (in the sense of [temp.spec] - a
801 specialization is either an instantiation or an explicit
802 specialization) of TMPL for the given template ARGS. If there is
803 no such specialization, return NULL_TREE. The ARGS are a vector of
804 arguments, or a vector of vectors of arguments, in the case of
805 templates with more than one level of parameters.
807 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
808 then we search for a partial specialization matching ARGS. This
809 parameter is ignored if TMPL is not a class template. */
812 retrieve_specialization (tree tmpl, tree args,
813 bool class_specializations_p)
815 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
817 /* There should be as many levels of arguments as there are
818 levels of parameters. */
819 gcc_assert (TMPL_ARGS_DEPTH (args)
820 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
822 if (optimize_specialization_lookup_p (tmpl))
825 tree class_specialization;
830 /* The template arguments actually apply to the containing
831 class. Find the class specialization with those
833 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
835 = retrieve_specialization (class_template, args,
836 /*class_specializations_p=*/false);
837 if (!class_specialization)
839 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
840 for the specialization. */
841 idx = class_method_index_for_fn (class_specialization, tmpl);
844 /* Iterate through the methods with the indicated name, looking
845 for the one that has an instance of TMPL. */
846 methods = CLASSTYPE_METHOD_VEC (class_specialization);
847 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
849 tree fn = OVL_CURRENT (fns);
850 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
860 /* Class templates store their instantiations on the
861 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
862 DECL_TEMPLATE_SPECIALIZATIONS list. */
863 if (!class_specializations_p
864 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
865 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
867 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
869 /* Iterate through the list until we find a matching template. */
870 while (*sp != NULL_TREE)
874 if (comp_template_args (TREE_PURPOSE (spec), args))
876 /* Use the move-to-front heuristic to speed up future
880 *sp = TREE_CHAIN (*sp);
881 TREE_CHAIN (spec) = *head;
884 return TREE_VALUE (spec);
886 sp = &TREE_CHAIN (spec);
893 /* Like retrieve_specialization, but for local declarations. */
896 retrieve_local_specialization (tree tmpl)
898 tree spec = htab_find_with_hash (local_specializations, tmpl,
899 htab_hash_pointer (tmpl));
900 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
903 /* Returns nonzero iff DECL is a specialization of TMPL. */
906 is_specialization_of (tree decl, tree tmpl)
910 if (TREE_CODE (decl) == FUNCTION_DECL)
914 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
920 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
922 for (t = TREE_TYPE (decl);
924 t = CLASSTYPE_USE_TEMPLATE (t)
925 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
926 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
933 /* Returns nonzero iff DECL is a specialization of friend declaration
934 FRIEND according to [temp.friend]. */
937 is_specialization_of_friend (tree decl, tree friend)
939 bool need_template = true;
942 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
943 || TREE_CODE (decl) == TYPE_DECL);
945 /* For [temp.friend/6] when FRIEND is an ordinary member function
946 of a template class, we want to check if DECL is a specialization
948 if (TREE_CODE (friend) == FUNCTION_DECL
949 && DECL_TEMPLATE_INFO (friend)
950 && !DECL_USE_TEMPLATE (friend))
952 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
953 friend = DECL_TI_TEMPLATE (friend);
954 need_template = false;
956 else if (TREE_CODE (friend) == TEMPLATE_DECL
957 && !PRIMARY_TEMPLATE_P (friend))
958 need_template = false;
960 /* There is nothing to do if this is not a template friend. */
961 if (TREE_CODE (friend) != TEMPLATE_DECL)
964 if (is_specialization_of (decl, friend))
968 A member of a class template may be declared to be a friend of a
969 non-template class. In this case, the corresponding member of
970 every specialization of the class template is a friend of the
971 class granting friendship.
973 For example, given a template friend declaration
975 template <class T> friend void A<T>::f();
977 the member function below is considered a friend
979 template <> struct A<int> {
983 For this type of template friend, TEMPLATE_DEPTH below will be
984 nonzero. To determine if DECL is a friend of FRIEND, we first
985 check if the enclosing class is a specialization of another. */
987 template_depth = template_class_depth (DECL_CONTEXT (friend));
989 && DECL_CLASS_SCOPE_P (decl)
990 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
991 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
993 /* Next, we check the members themselves. In order to handle
994 a few tricky cases, such as when FRIEND's are
996 template <class T> friend void A<T>::g(T t);
997 template <class T> template <T t> friend void A<T>::h();
1001 void A<int>::g(int);
1002 template <int> void A<int>::h();
1004 we need to figure out ARGS, the template arguments from
1005 the context of DECL. This is required for template substitution
1006 of `T' in the function parameter of `g' and template parameter
1007 of `h' in the above examples. Here ARGS corresponds to `int'. */
1009 tree context = DECL_CONTEXT (decl);
1010 tree args = NULL_TREE;
1011 int current_depth = 0;
1013 while (current_depth < template_depth)
1015 if (CLASSTYPE_TEMPLATE_INFO (context))
1017 if (current_depth == 0)
1018 args = TYPE_TI_ARGS (context);
1020 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1023 context = TYPE_CONTEXT (context);
1026 if (TREE_CODE (decl) == FUNCTION_DECL)
1031 tree friend_args_type;
1032 tree decl_args_type;
1034 /* Make sure that both DECL and FRIEND are templates or
1036 is_template = DECL_TEMPLATE_INFO (decl)
1037 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1038 if (need_template ^ is_template)
1040 else if (is_template)
1042 /* If both are templates, check template parameter list. */
1044 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1046 if (!comp_template_parms
1047 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1051 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1054 decl_type = TREE_TYPE (decl);
1056 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1057 tf_none, NULL_TREE);
1058 if (friend_type == error_mark_node)
1061 /* Check if return types match. */
1062 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1065 /* Check if function parameter types match, ignoring the
1066 `this' parameter. */
1067 friend_args_type = TYPE_ARG_TYPES (friend_type);
1068 decl_args_type = TYPE_ARG_TYPES (decl_type);
1069 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1070 friend_args_type = TREE_CHAIN (friend_args_type);
1071 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1072 decl_args_type = TREE_CHAIN (decl_args_type);
1074 return compparms (decl_args_type, friend_args_type);
1078 /* DECL is a TYPE_DECL */
1080 tree decl_type = TREE_TYPE (decl);
1082 /* Make sure that both DECL and FRIEND are templates or
1085 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1086 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1088 if (need_template ^ is_template)
1090 else if (is_template)
1093 /* If both are templates, check the name of the two
1094 TEMPLATE_DECL's first because is_friend didn't. */
1095 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1096 != DECL_NAME (friend))
1099 /* Now check template parameter list. */
1101 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1103 return comp_template_parms
1104 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1108 return (DECL_NAME (decl)
1109 == DECL_NAME (friend));
1115 /* Register the specialization SPEC as a specialization of TMPL with
1116 the indicated ARGS. Returns SPEC, or an equivalent prior
1117 declaration, if available. */
1120 register_specialization (tree spec, tree tmpl, tree args)
1124 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1126 if (TREE_CODE (spec) == FUNCTION_DECL
1127 && uses_template_parms (DECL_TI_ARGS (spec)))
1128 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1129 register it; we want the corresponding TEMPLATE_DECL instead.
1130 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1131 the more obvious `uses_template_parms (spec)' to avoid problems
1132 with default function arguments. In particular, given
1133 something like this:
1135 template <class T> void f(T t1, T t = T())
1137 the default argument expression is not substituted for in an
1138 instantiation unless and until it is actually needed. */
1141 /* There should be as many levels of arguments as there are
1142 levels of parameters. */
1143 gcc_assert (TMPL_ARGS_DEPTH (args)
1144 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
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",
1168 /* This situation should occur only if the first
1169 specialization is an implicit instantiation, the
1170 second is an explicit specialization, and the
1171 implicit instantiation has not yet been used. That
1172 situation can occur if we have implicitly
1173 instantiated a member function and then specialized
1176 We can also wind up here if a friend declaration that
1177 looked like an instantiation turns out to be a
1180 template <class T> void foo(T);
1181 class S { friend void foo<>(int) };
1182 template <> void foo(int);
1184 We transform the existing DECL in place so that any
1185 pointers to it become pointers to the updated
1188 If there was a definition for the template, but not
1189 for the specialization, we want this to look as if
1190 there were no definition, and vice versa. */
1191 DECL_INITIAL (fn) = NULL_TREE;
1192 duplicate_decls (spec, fn);
1197 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1199 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
1200 /* Dup decl failed, but this is a new definition. Set the
1201 line number so any errors match this new
1203 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1209 /* A specialization must be declared in the same namespace as the
1210 template it is specializing. */
1211 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1212 && !check_specialization_namespace (tmpl))
1213 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1215 if (!optimize_specialization_lookup_p (tmpl))
1216 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1217 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1222 /* Unregister the specialization SPEC as a specialization of TMPL.
1223 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1224 if the SPEC was listed as a specialization of TMPL. */
1227 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1231 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1233 s = &TREE_CHAIN (*s))
1234 if (TREE_VALUE (*s) == spec)
1237 *s = TREE_CHAIN (*s);
1239 TREE_VALUE (*s) = new_spec;
1246 /* Compare an entry in the local specializations hash table P1 (which
1247 is really a pointer to a TREE_LIST) with P2 (which is really a
1251 eq_local_specializations (const void *p1, const void *p2)
1253 return TREE_VALUE ((tree) p1) == (tree) p2;
1256 /* Hash P1, an entry in the local specializations table. */
1259 hash_local_specialization (const void* p1)
1261 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1264 /* Like register_specialization, but for local declarations. We are
1265 registering SPEC, an instantiation of TMPL. */
1268 register_local_specialization (tree spec, tree tmpl)
1272 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1273 htab_hash_pointer (tmpl), INSERT);
1274 *slot = build_tree_list (spec, tmpl);
1277 /* Print the list of candidate FNS in an error message. */
1280 print_candidates (tree fns)
1284 const char *str = "candidates are:";
1286 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1290 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1291 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
1296 /* Returns the template (one of the functions given by TEMPLATE_ID)
1297 which can be specialized to match the indicated DECL with the
1298 explicit template args given in TEMPLATE_ID. The DECL may be
1299 NULL_TREE if none is available. In that case, the functions in
1300 TEMPLATE_ID are non-members.
1302 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1303 specialization of a member template.
1305 The TEMPLATE_COUNT is the number of references to qualifying
1306 template classes that appeared in the name of the function. See
1307 check_explicit_specialization for a more accurate description.
1309 The template args (those explicitly specified and those deduced)
1310 are output in a newly created vector *TARGS_OUT.
1312 If it is impossible to determine the result, an error message is
1313 issued. The error_mark_node is returned to indicate failure. */
1316 determine_specialization (tree template_id,
1319 int need_member_template,
1324 tree explicit_targs;
1325 tree candidates = NULL_TREE;
1326 tree templates = NULL_TREE;
1328 struct cp_binding_level *b;
1330 *targs_out = NULL_TREE;
1332 if (template_id == error_mark_node)
1333 return error_mark_node;
1335 fns = TREE_OPERAND (template_id, 0);
1336 explicit_targs = TREE_OPERAND (template_id, 1);
1338 if (fns == error_mark_node)
1339 return error_mark_node;
1341 /* Check for baselinks. */
1342 if (BASELINK_P (fns))
1343 fns = BASELINK_FUNCTIONS (fns);
1345 if (!is_overloaded_fn (fns))
1347 error ("%qD is not a function template", fns);
1348 return error_mark_node;
1351 /* Count the number of template headers specified for this
1354 for (b = current_binding_level;
1355 b->kind == sk_template_parms || b->kind == sk_template_spec;
1359 for (; fns; fns = OVL_NEXT (fns))
1361 tree fn = OVL_CURRENT (fns);
1363 if (TREE_CODE (fn) == TEMPLATE_DECL)
1365 tree decl_arg_types;
1368 /* DECL might be a specialization of FN. */
1370 /* Adjust the type of DECL in case FN is a static member. */
1371 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1372 if (DECL_STATIC_FUNCTION_P (fn)
1373 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1374 decl_arg_types = TREE_CHAIN (decl_arg_types);
1376 /* Check that the number of function parameters matches.
1378 template <class T> void f(int i = 0);
1379 template <> void f<int>();
1380 The specialization f<int> is invalid but is not caught
1381 by get_bindings below. */
1383 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1384 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1387 /* For a non-static member function, we need to make sure that
1388 the const qualification is the same. This can be done by
1389 checking the 'this' in the argument list. */
1390 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1391 && !same_type_p (TREE_VALUE (fn_arg_types),
1392 TREE_VALUE (decl_arg_types)))
1395 /* In case of explicit specialization, we need to check if
1396 the number of template headers appearing in the specialization
1397 is correct. This is usually done in check_explicit_specialization,
1398 but the check done there cannot be exhaustive when specializing
1399 member functions. Consider the following code:
1401 template <> void A<int>::f(int);
1402 template <> template <> void A<int>::f(int);
1404 Assuming that A<int> is not itself an explicit specialization
1405 already, the first line specializes "f" which is a non-template
1406 member function, whilst the second line specializes "f" which
1407 is a template member function. So both lines are syntactically
1408 correct, and check_explicit_specialization does not reject
1411 Here, we can do better, as we are matching the specialization
1412 against the declarations. We count the number of template
1413 headers, and we check if they match TEMPLATE_COUNT + 1
1414 (TEMPLATE_COUNT is the number of qualifying template classes,
1415 plus there must be another header for the member template
1418 Notice that if header_count is zero, this is not a
1419 specialization but rather a template instantiation, so there
1420 is no check we can perform here. */
1421 if (header_count && header_count != template_count + 1)
1424 /* See whether this function might be a specialization of this
1426 targs = get_bindings (fn, decl, explicit_targs);
1429 /* We cannot deduce template arguments that when used to
1430 specialize TMPL will produce DECL. */
1433 /* Save this template, and the arguments deduced. */
1434 templates = tree_cons (targs, fn, templates);
1436 else if (need_member_template)
1437 /* FN is an ordinary member function, and we need a
1438 specialization of a member template. */
1440 else if (TREE_CODE (fn) != FUNCTION_DECL)
1441 /* We can get IDENTIFIER_NODEs here in certain erroneous
1444 else if (!DECL_FUNCTION_MEMBER_P (fn))
1445 /* This is just an ordinary non-member function. Nothing can
1446 be a specialization of that. */
1448 else if (DECL_ARTIFICIAL (fn))
1449 /* Cannot specialize functions that are created implicitly. */
1453 tree decl_arg_types;
1455 /* This is an ordinary member function. However, since
1456 we're here, we can assume it's enclosing class is a
1457 template class. For example,
1459 template <typename T> struct S { void f(); };
1460 template <> void S<int>::f() {}
1462 Here, S<int>::f is a non-template, but S<int> is a
1463 template class. If FN has the same type as DECL, we
1464 might be in business. */
1466 if (!DECL_TEMPLATE_INFO (fn))
1467 /* Its enclosing class is an explicit specialization
1468 of a template class. This is not a candidate. */
1471 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1472 TREE_TYPE (TREE_TYPE (fn))))
1473 /* The return types differ. */
1476 /* Adjust the type of DECL in case FN is a static member. */
1477 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1478 if (DECL_STATIC_FUNCTION_P (fn)
1479 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1480 decl_arg_types = TREE_CHAIN (decl_arg_types);
1482 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1485 candidates = tree_cons (NULL_TREE, fn, candidates);
1489 if (templates && TREE_CHAIN (templates))
1495 It is possible for a specialization with a given function
1496 signature to be instantiated from more than one function
1497 template. In such cases, explicit specification of the
1498 template arguments must be used to uniquely identify the
1499 function template specialization being specialized.
1501 Note that here, there's no suggestion that we're supposed to
1502 determine which of the candidate templates is most
1503 specialized. However, we, also have:
1507 Partial ordering of overloaded function template
1508 declarations is used in the following contexts to select
1509 the function template to which a function template
1510 specialization refers:
1512 -- when an explicit specialization refers to a function
1515 So, we do use the partial ordering rules, at least for now.
1516 This extension can only serve to make invalid programs valid,
1517 so it's safe. And, there is strong anecdotal evidence that
1518 the committee intended the partial ordering rules to apply;
1519 the EDG front-end has that behavior, and John Spicer claims
1520 that the committee simply forgot to delete the wording in
1521 [temp.expl.spec]. */
1522 tree tmpl = most_specialized (templates, decl, explicit_targs);
1523 if (tmpl && tmpl != error_mark_node)
1525 targs = get_bindings (tmpl, decl, explicit_targs);
1526 templates = tree_cons (targs, tmpl, NULL_TREE);
1530 if (templates == NULL_TREE && candidates == NULL_TREE)
1532 cp_error_at ("template-id %qD for %q+D does not match any template "
1535 return error_mark_node;
1537 else if ((templates && TREE_CHAIN (templates))
1538 || (candidates && TREE_CHAIN (candidates))
1539 || (templates && candidates))
1541 cp_error_at ("ambiguous template specialization %qD for %q+D",
1543 chainon (candidates, templates);
1544 print_candidates (candidates);
1545 return error_mark_node;
1548 /* We have one, and exactly one, match. */
1551 /* It was a specialization of an ordinary member function in a
1553 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1554 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1557 /* It was a specialization of a template. */
1558 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1559 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1561 *targs_out = copy_node (targs);
1562 SET_TMPL_ARGS_LEVEL (*targs_out,
1563 TMPL_ARGS_DEPTH (*targs_out),
1564 TREE_PURPOSE (templates));
1567 *targs_out = TREE_PURPOSE (templates);
1568 return TREE_VALUE (templates);
1571 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1572 but with the default argument values filled in from those in the
1576 copy_default_args_to_explicit_spec_1 (tree spec_types,
1579 tree new_spec_types;
1584 if (spec_types == void_list_node)
1585 return void_list_node;
1587 /* Substitute into the rest of the list. */
1589 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1590 TREE_CHAIN (tmpl_types));
1592 /* Add the default argument for this parameter. */
1593 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1594 TREE_VALUE (spec_types),
1598 /* DECL is an explicit specialization. Replicate default arguments
1599 from the template it specializes. (That way, code like:
1601 template <class T> void f(T = 3);
1602 template <> void f(double);
1605 works, as required.) An alternative approach would be to look up
1606 the correct default arguments at the call-site, but this approach
1607 is consistent with how implicit instantiations are handled. */
1610 copy_default_args_to_explicit_spec (tree decl)
1615 tree new_spec_types;
1619 tree object_type = NULL_TREE;
1620 tree in_charge = NULL_TREE;
1621 tree vtt = NULL_TREE;
1623 /* See if there's anything we need to do. */
1624 tmpl = DECL_TI_TEMPLATE (decl);
1625 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1626 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1627 if (TREE_PURPOSE (t))
1632 old_type = TREE_TYPE (decl);
1633 spec_types = TYPE_ARG_TYPES (old_type);
1635 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1637 /* Remove the this pointer, but remember the object's type for
1639 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1640 spec_types = TREE_CHAIN (spec_types);
1641 tmpl_types = TREE_CHAIN (tmpl_types);
1643 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1645 /* DECL may contain more parameters than TMPL due to the extra
1646 in-charge parameter in constructors and destructors. */
1647 in_charge = spec_types;
1648 spec_types = TREE_CHAIN (spec_types);
1650 if (DECL_HAS_VTT_PARM_P (decl))
1653 spec_types = TREE_CHAIN (spec_types);
1657 /* Compute the merged default arguments. */
1659 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1661 /* Compute the new FUNCTION_TYPE. */
1665 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1670 /* Put the in-charge parameter back. */
1671 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1672 TREE_VALUE (in_charge),
1675 new_type = build_method_type_directly (object_type,
1676 TREE_TYPE (old_type),
1680 new_type = build_function_type (TREE_TYPE (old_type),
1682 new_type = cp_build_type_attribute_variant (new_type,
1683 TYPE_ATTRIBUTES (old_type));
1684 new_type = build_exception_variant (new_type,
1685 TYPE_RAISES_EXCEPTIONS (old_type));
1686 TREE_TYPE (decl) = new_type;
1689 /* Check to see if the function just declared, as indicated in
1690 DECLARATOR, and in DECL, is a specialization of a function
1691 template. We may also discover that the declaration is an explicit
1692 instantiation at this point.
1694 Returns DECL, or an equivalent declaration that should be used
1695 instead if all goes well. Issues an error message if something is
1696 amiss. Returns error_mark_node if the error is not easily
1699 FLAGS is a bitmask consisting of the following flags:
1701 2: The function has a definition.
1702 4: The function is a friend.
1704 The TEMPLATE_COUNT is the number of references to qualifying
1705 template classes that appeared in the name of the function. For
1708 template <class T> struct S { void f(); };
1711 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1712 classes are not counted in the TEMPLATE_COUNT, so that in
1714 template <class T> struct S {};
1715 template <> struct S<int> { void f(); }
1716 template <> void S<int>::f();
1718 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1719 invalid; there should be no template <>.)
1721 If the function is a specialization, it is marked as such via
1722 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1723 is set up correctly, and it is added to the list of specializations
1724 for that template. */
1727 check_explicit_specialization (tree declarator,
1732 int have_def = flags & 2;
1733 int is_friend = flags & 4;
1734 int specialization = 0;
1735 int explicit_instantiation = 0;
1736 int member_specialization = 0;
1737 tree ctype = DECL_CLASS_CONTEXT (decl);
1738 tree dname = DECL_NAME (decl);
1741 tsk = current_tmpl_spec_kind (template_count);
1746 if (processing_specialization)
1749 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1751 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1754 /* This could be something like:
1756 template <class T> void f(T);
1757 class S { friend void f<>(int); } */
1761 /* This case handles bogus declarations like template <>
1762 template <class T> void f<int>(); */
1764 error ("template-id %qD in declaration of primary template",
1771 case tsk_invalid_member_spec:
1772 /* The error has already been reported in
1773 check_specialization_scope. */
1774 return error_mark_node;
1776 case tsk_invalid_expl_inst:
1777 error ("template parameter list used in explicit instantiation");
1783 error ("definition provided for explicit instantiation");
1785 explicit_instantiation = 1;
1788 case tsk_excessive_parms:
1789 case tsk_insufficient_parms:
1790 if (tsk == tsk_excessive_parms)
1791 error ("too many template parameter lists in declaration of %qD",
1793 else if (template_header_count)
1794 error("too few template parameter lists in declaration of %qD", decl);
1796 error("explicit specialization of %qD must be introduced by "
1797 "%<template <>%>", decl);
1801 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1803 member_specialization = 1;
1809 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1811 /* This case handles bogus declarations like template <>
1812 template <class T> void f<int>(); */
1814 if (uses_template_parms (declarator))
1815 error ("function template partial specialization %qD "
1816 "is not allowed", declarator);
1818 error ("template-id %qD in declaration of primary template",
1823 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1824 /* This is a specialization of a member template, without
1825 specialization the containing class. Something like:
1827 template <class T> struct S {
1828 template <class U> void f (U);
1830 template <> template <class U> void S<int>::f(U) {}
1832 That's a specialization -- but of the entire template. */
1840 if (specialization || member_specialization)
1842 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1843 for (; t; t = TREE_CHAIN (t))
1844 if (TREE_PURPOSE (t))
1847 ("default argument specified in explicit specialization");
1850 if (current_lang_name == lang_name_c)
1851 error ("template specialization with C linkage");
1854 if (specialization || member_specialization || explicit_instantiation)
1856 tree tmpl = NULL_TREE;
1857 tree targs = NULL_TREE;
1859 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1860 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1864 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1869 /* If there is no class context, the explicit instantiation
1870 must be at namespace scope. */
1871 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1873 /* Find the namespace binding, using the declaration
1875 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1878 declarator = lookup_template_function (fns, NULL_TREE);
1881 if (declarator == error_mark_node)
1882 return error_mark_node;
1884 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1886 if (!explicit_instantiation)
1887 /* A specialization in class scope. This is invalid,
1888 but the error will already have been flagged by
1889 check_specialization_scope. */
1890 return error_mark_node;
1893 /* It's not valid to write an explicit instantiation in
1896 class C { template void f(); }
1898 This case is caught by the parser. However, on
1901 template class C { void f(); };
1903 (which is invalid) we can get here. The error will be
1910 else if (ctype != NULL_TREE
1911 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1914 /* Find the list of functions in ctype that have the same
1915 name as the declared function. */
1916 tree name = TREE_OPERAND (declarator, 0);
1917 tree fns = NULL_TREE;
1920 if (constructor_name_p (name, ctype))
1922 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1924 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1925 : !TYPE_HAS_DESTRUCTOR (ctype))
1927 /* From [temp.expl.spec]:
1929 If such an explicit specialization for the member
1930 of a class template names an implicitly-declared
1931 special member function (clause _special_), the
1932 program is ill-formed.
1934 Similar language is found in [temp.explicit]. */
1935 error ("specialization of implicitly-declared special member function");
1936 return error_mark_node;
1939 name = is_constructor ? ctor_identifier : dtor_identifier;
1942 if (!DECL_CONV_FN_P (decl))
1944 idx = lookup_fnfields_1 (ctype, name);
1946 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1953 /* For a type-conversion operator, we cannot do a
1954 name-based lookup. We might be looking for `operator
1955 int' which will be a specialization of `operator T'.
1956 So, we find *all* the conversion operators, and then
1957 select from them. */
1960 methods = CLASSTYPE_METHOD_VEC (ctype);
1962 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1963 VEC_iterate (tree, methods, idx, ovl);
1966 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1967 /* There are no more conversion functions. */
1970 /* Glue all these conversion functions together
1971 with those we already have. */
1972 for (; ovl; ovl = OVL_NEXT (ovl))
1973 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1977 if (fns == NULL_TREE)
1979 error ("no member function %qD declared in %qT", name, ctype);
1980 return error_mark_node;
1983 TREE_OPERAND (declarator, 0) = fns;
1986 /* Figure out what exactly is being specialized at this point.
1987 Note that for an explicit instantiation, even one for a
1988 member function, we cannot tell apriori whether the
1989 instantiation is for a member template, or just a member
1990 function of a template class. Even if a member template is
1991 being instantiated, the member template arguments may be
1992 elided if they can be deduced from the rest of the
1994 tmpl = determine_specialization (declarator, decl,
1996 member_specialization,
1999 if (!tmpl || tmpl == error_mark_node)
2000 /* We couldn't figure out what this declaration was
2002 return error_mark_node;
2005 tree gen_tmpl = most_general_template (tmpl);
2007 if (explicit_instantiation)
2009 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2010 is done by do_decl_instantiation later. */
2012 int arg_depth = TMPL_ARGS_DEPTH (targs);
2013 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2015 if (arg_depth > parm_depth)
2017 /* If TMPL is not the most general template (for
2018 example, if TMPL is a friend template that is
2019 injected into namespace scope), then there will
2020 be too many levels of TARGS. Remove some of them
2025 new_targs = make_tree_vec (parm_depth);
2026 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2027 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2028 = TREE_VEC_ELT (targs, i);
2032 return instantiate_template (tmpl, targs, tf_error);
2035 /* If we thought that the DECL was a member function, but it
2036 turns out to be specializing a static member function,
2037 make DECL a static member function as well. */
2038 if (DECL_STATIC_FUNCTION_P (tmpl)
2039 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2040 revert_static_member_fn (decl);
2042 /* If this is a specialization of a member template of a
2043 template class. In we want to return the TEMPLATE_DECL,
2044 not the specialization of it. */
2045 if (tsk == tsk_template)
2047 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2048 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2051 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2052 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2053 = DECL_SOURCE_LOCATION (decl);
2058 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2059 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2061 /* Inherit default function arguments from the template
2062 DECL is specializing. */
2063 copy_default_args_to_explicit_spec (decl);
2065 /* This specialization has the same protection as the
2066 template it specializes. */
2067 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2068 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2070 if (is_friend && !have_def)
2071 /* This is not really a declaration of a specialization.
2072 It's just the name of an instantiation. But, it's not
2073 a request for an instantiation, either. */
2074 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2075 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2076 /* This is indeed a specialization. In case of constructors
2077 and destructors, we need in-charge and not-in-charge
2078 versions in V3 ABI. */
2079 clone_function_decl (decl, /*update_method_vec_p=*/0);
2081 /* Register this specialization so that we can find it
2083 decl = register_specialization (decl, gen_tmpl, targs);
2090 /* TYPE is being declared. Verify that the use of template headers
2091 and such is reasonable. Issue error messages if not. */
2094 maybe_check_template_type (tree type)
2096 if (template_header_count)
2098 /* We are in the scope of some `template <...>' header. */
2101 = template_class_depth_real (TYPE_CONTEXT (type),
2102 /*count_specializations=*/1);
2104 if (template_header_count <= context_depth)
2105 /* This is OK; the template headers are for the context. We
2106 are actually too lenient here; like
2107 check_explicit_specialization we should consider the number
2108 of template types included in the actual declaration. For
2111 template <class T> struct S {
2112 template <class U> template <class V>
2118 template <class T> struct S {
2119 template <class U> struct I;
2122 template <class T> template <class U.
2127 else if (template_header_count > context_depth + 1)
2128 /* There are two many template parameter lists. */
2129 error ("too many template parameter lists in declaration of %qT", type);
2133 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2134 parameters. These are represented in the same format used for
2135 DECL_TEMPLATE_PARMS. */
2138 comp_template_parms (tree parms1, tree parms2)
2143 if (parms1 == parms2)
2146 for (p1 = parms1, p2 = parms2;
2147 p1 != NULL_TREE && p2 != NULL_TREE;
2148 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2150 tree t1 = TREE_VALUE (p1);
2151 tree t2 = TREE_VALUE (p2);
2154 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2155 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2157 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2160 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2162 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2163 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2165 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2168 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2170 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2175 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2176 /* One set of parameters has more parameters lists than the
2183 /* Complain if DECL shadows a template parameter.
2185 [temp.local]: A template-parameter shall not be redeclared within its
2186 scope (including nested scopes). */
2189 check_template_shadow (tree decl)
2193 /* If we're not in a template, we can't possibly shadow a template
2195 if (!current_template_parms)
2198 /* Figure out what we're shadowing. */
2199 if (TREE_CODE (decl) == OVERLOAD)
2200 decl = OVL_CURRENT (decl);
2201 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2203 /* If there's no previous binding for this name, we're not shadowing
2204 anything, let alone a template parameter. */
2208 /* If we're not shadowing a template parameter, we're done. Note
2209 that OLDDECL might be an OVERLOAD (or perhaps even an
2210 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2212 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2215 /* We check for decl != olddecl to avoid bogus errors for using a
2216 name inside a class. We check TPFI to avoid duplicate errors for
2217 inline member templates. */
2219 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2222 cp_error_at ("declaration of %q#D", decl);
2223 cp_error_at (" shadows template parm %q#D", olddecl);
2226 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2227 ORIG_LEVEL, DECL, and TYPE. */
2230 build_template_parm_index (int index,
2236 tree t = make_node (TEMPLATE_PARM_INDEX);
2237 TEMPLATE_PARM_IDX (t) = index;
2238 TEMPLATE_PARM_LEVEL (t) = level;
2239 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2240 TEMPLATE_PARM_DECL (t) = decl;
2241 TREE_TYPE (t) = type;
2242 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2243 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2244 TREE_READONLY (t) = TREE_READONLY (decl);
2249 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2250 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2251 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2252 new one is created. */
2255 reduce_template_parm_level (tree index, tree type, int levels)
2257 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2258 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2259 != TEMPLATE_PARM_LEVEL (index) - levels))
2261 tree orig_decl = TEMPLATE_PARM_DECL (index);
2264 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2265 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2266 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2267 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2268 DECL_ARTIFICIAL (decl) = 1;
2269 SET_DECL_TEMPLATE_PARM_P (decl);
2271 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2272 TEMPLATE_PARM_LEVEL (index) - levels,
2273 TEMPLATE_PARM_ORIG_LEVEL (index),
2275 TEMPLATE_PARM_DESCENDANTS (index) = t;
2277 /* Template template parameters need this. */
2278 DECL_TEMPLATE_PARMS (decl)
2279 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2282 return TEMPLATE_PARM_DESCENDANTS (index);
2285 /* Process information from new template parameter NEXT and append it to the
2286 LIST being built. This new parameter is a non-type parameter iff
2287 IS_NON_TYPE is true. */
2290 process_template_parm (tree list, tree next, bool is_non_type)
2298 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2299 defval = TREE_PURPOSE (parm);
2303 tree p = TREE_VALUE (tree_last (list));
2305 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2306 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2308 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2316 parm = TREE_VALUE (parm);
2318 SET_DECL_TEMPLATE_PARM_P (parm);
2322 The top-level cv-qualifiers on the template-parameter are
2323 ignored when determining its type. */
2324 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2326 /* A template parameter is not modifiable. */
2327 TREE_CONSTANT (parm) = 1;
2328 TREE_INVARIANT (parm) = 1;
2329 TREE_READONLY (parm) = 1;
2330 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2331 TREE_TYPE (parm) = void_type_node;
2332 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2333 TREE_CONSTANT (decl) = 1;
2334 TREE_INVARIANT (decl) = 1;
2335 TREE_READONLY (decl) = 1;
2336 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2337 = build_template_parm_index (idx, processing_template_decl,
2338 processing_template_decl,
2339 decl, TREE_TYPE (parm));
2344 parm = TREE_VALUE (TREE_VALUE (parm));
2346 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2348 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2349 /* This is for distinguishing between real templates and template
2350 template parameters */
2351 TREE_TYPE (parm) = t;
2352 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2357 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2358 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2359 decl = build_decl (TYPE_DECL, parm, t);
2362 TYPE_NAME (t) = decl;
2363 TYPE_STUB_DECL (t) = decl;
2365 TEMPLATE_TYPE_PARM_INDEX (t)
2366 = build_template_parm_index (idx, processing_template_decl,
2367 processing_template_decl,
2368 decl, TREE_TYPE (parm));
2370 DECL_ARTIFICIAL (decl) = 1;
2371 SET_DECL_TEMPLATE_PARM_P (decl);
2373 parm = build_tree_list (defval, parm);
2374 return chainon (list, parm);
2377 /* The end of a template parameter list has been reached. Process the
2378 tree list into a parameter vector, converting each parameter into a more
2379 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2383 end_template_parm_list (tree parms)
2387 tree saved_parmlist = make_tree_vec (list_length (parms));
2389 current_template_parms
2390 = tree_cons (size_int (processing_template_decl),
2391 saved_parmlist, current_template_parms);
2393 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2395 next = TREE_CHAIN (parm);
2396 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2397 TREE_CHAIN (parm) = NULL_TREE;
2400 --processing_template_parmlist;
2402 return saved_parmlist;
2405 /* end_template_decl is called after a template declaration is seen. */
2408 end_template_decl (void)
2410 reset_specialization ();
2412 if (! processing_template_decl)
2415 /* This matches the pushlevel in begin_template_parm_list. */
2418 --processing_template_decl;
2419 current_template_parms = TREE_CHAIN (current_template_parms);
2422 /* Given a template argument vector containing the template PARMS.
2423 The innermost PARMS are given first. */
2426 current_template_args (void)
2429 tree args = NULL_TREE;
2430 int length = TMPL_PARMS_DEPTH (current_template_parms);
2433 /* If there is only one level of template parameters, we do not
2434 create a TREE_VEC of TREE_VECs. Instead, we return a single
2435 TREE_VEC containing the arguments. */
2437 args = make_tree_vec (length);
2439 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2441 tree a = copy_node (TREE_VALUE (header));
2444 TREE_TYPE (a) = NULL_TREE;
2445 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2447 tree t = TREE_VEC_ELT (a, i);
2449 /* T will be a list if we are called from within a
2450 begin/end_template_parm_list pair, but a vector directly
2451 if within a begin/end_member_template_processing pair. */
2452 if (TREE_CODE (t) == TREE_LIST)
2456 if (TREE_CODE (t) == TYPE_DECL
2457 || TREE_CODE (t) == TEMPLATE_DECL)
2460 t = DECL_INITIAL (t);
2461 TREE_VEC_ELT (a, i) = t;
2466 TREE_VEC_ELT (args, --l) = a;
2474 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2475 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2476 a member template. Used by push_template_decl below. */
2479 build_template_decl (tree decl, tree parms, bool member_template_p)
2481 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2482 DECL_TEMPLATE_PARMS (tmpl) = parms;
2483 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2484 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2485 if (DECL_LANG_SPECIFIC (decl))
2487 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2488 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2489 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2490 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2491 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2492 if (DECL_OVERLOADED_OPERATOR_P (decl))
2493 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2494 DECL_OVERLOADED_OPERATOR_P (decl));
2500 struct template_parm_data
2502 /* The level of the template parameters we are currently
2506 /* The index of the specialization argument we are currently
2510 /* An array whose size is the number of template parameters. The
2511 elements are nonzero if the parameter has been used in any one
2512 of the arguments processed so far. */
2515 /* An array whose size is the number of template arguments. The
2516 elements are nonzero if the argument makes use of template
2517 parameters of this level. */
2518 int* arg_uses_template_parms;
2521 /* Subroutine of push_template_decl used to see if each template
2522 parameter in a partial specialization is used in the explicit
2523 argument list. If T is of the LEVEL given in DATA (which is
2524 treated as a template_parm_data*), then DATA->PARMS is marked
2528 mark_template_parm (tree t, void* data)
2532 struct template_parm_data* tpd = (struct template_parm_data*) data;
2534 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2536 level = TEMPLATE_PARM_LEVEL (t);
2537 idx = TEMPLATE_PARM_IDX (t);
2541 level = TEMPLATE_TYPE_LEVEL (t);
2542 idx = TEMPLATE_TYPE_IDX (t);
2545 if (level == tpd->level)
2547 tpd->parms[idx] = 1;
2548 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2551 /* Return zero so that for_each_template_parm will continue the
2552 traversal of the tree; we want to mark *every* template parm. */
2556 /* Process the partial specialization DECL. */
2559 process_partial_specialization (tree decl)
2561 tree type = TREE_TYPE (decl);
2562 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2563 tree specargs = CLASSTYPE_TI_ARGS (type);
2564 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2565 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2566 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2567 int nargs = TREE_VEC_LENGTH (inner_args);
2568 int ntparms = TREE_VEC_LENGTH (inner_parms);
2570 int did_error_intro = 0;
2571 struct template_parm_data tpd;
2572 struct template_parm_data tpd2;
2574 /* We check that each of the template parameters given in the
2575 partial specialization is used in the argument list to the
2576 specialization. For example:
2578 template <class T> struct S;
2579 template <class T> struct S<T*>;
2581 The second declaration is OK because `T*' uses the template
2582 parameter T, whereas
2584 template <class T> struct S<int>;
2586 is no good. Even trickier is:
2597 The S2<T> declaration is actually invalid; it is a
2598 full-specialization. Of course,
2601 struct S2<T (*)(U)>;
2603 or some such would have been OK. */
2604 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2605 tpd.parms = alloca (sizeof (int) * ntparms);
2606 memset (tpd.parms, 0, sizeof (int) * ntparms);
2608 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2609 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2610 for (i = 0; i < nargs; ++i)
2612 tpd.current_arg = i;
2613 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2614 &mark_template_parm,
2618 for (i = 0; i < ntparms; ++i)
2619 if (tpd.parms[i] == 0)
2621 /* One of the template parms was not used in the
2623 if (!did_error_intro)
2625 error ("template parameters not used in partial specialization:");
2626 did_error_intro = 1;
2629 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2632 /* [temp.class.spec]
2634 The argument list of the specialization shall not be identical to
2635 the implicit argument list of the primary template. */
2636 if (comp_template_args
2638 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2640 error ("partial specialization %qT does not specialize any template arguments", type);
2642 /* [temp.class.spec]
2644 A partially specialized non-type argument expression shall not
2645 involve template parameters of the partial specialization except
2646 when the argument expression is a simple identifier.
2648 The type of a template parameter corresponding to a specialized
2649 non-type argument shall not be dependent on a parameter of the
2651 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2653 for (i = 0; i < nargs; ++i)
2655 tree arg = TREE_VEC_ELT (inner_args, i);
2656 if (/* These first two lines are the `non-type' bit. */
2658 && TREE_CODE (arg) != TEMPLATE_DECL
2659 /* This next line is the `argument expression is not just a
2660 simple identifier' condition and also the `specialized
2661 non-type argument' bit. */
2662 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2664 if (tpd.arg_uses_template_parms[i])
2665 error ("template argument %qE involves template parameter(s)", arg);
2668 /* Look at the corresponding template parameter,
2669 marking which template parameters its type depends
2672 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2677 /* We haven't yet initialized TPD2. Do so now. */
2678 tpd2.arg_uses_template_parms
2679 = alloca (sizeof (int) * nargs);
2680 /* The number of parameters here is the number in the
2681 main template, which, as checked in the assertion
2683 tpd2.parms = alloca (sizeof (int) * nargs);
2685 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2688 /* Mark the template parameters. But this time, we're
2689 looking for the template parameters of the main
2690 template, not in the specialization. */
2691 tpd2.current_arg = i;
2692 tpd2.arg_uses_template_parms[i] = 0;
2693 memset (tpd2.parms, 0, sizeof (int) * nargs);
2694 for_each_template_parm (type,
2695 &mark_template_parm,
2699 if (tpd2.arg_uses_template_parms [i])
2701 /* The type depended on some template parameters.
2702 If they are fully specialized in the
2703 specialization, that's OK. */
2705 for (j = 0; j < nargs; ++j)
2706 if (tpd2.parms[j] != 0
2707 && tpd.arg_uses_template_parms [j])
2709 error ("type %qT of template argument %qE depends "
2710 "on template parameter(s)",
2720 if (retrieve_specialization (maintmpl, specargs,
2721 /*class_specializations_p=*/true))
2722 /* We've already got this specialization. */
2725 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2726 = tree_cons (inner_args, inner_parms,
2727 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2728 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2732 /* Check that a template declaration's use of default arguments is not
2733 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2734 nonzero if DECL is the thing declared by a primary template.
2735 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2738 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2741 int last_level_to_check;
2746 A default template-argument shall not be specified in a
2747 function template declaration or a function template definition, nor
2748 in the template-parameter-list of the definition of a member of a
2751 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2752 /* You can't have a function template declaration in a local
2753 scope, nor you can you define a member of a class template in a
2757 if (current_class_type
2758 && !TYPE_BEING_DEFINED (current_class_type)
2759 && DECL_LANG_SPECIFIC (decl)
2760 /* If this is either a friend defined in the scope of the class
2761 or a member function. */
2762 && (DECL_FUNCTION_MEMBER_P (decl)
2763 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2764 : DECL_FRIEND_CONTEXT (decl)
2765 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2767 /* And, if it was a member function, it really was defined in
2768 the scope of the class. */
2769 && (!DECL_FUNCTION_MEMBER_P (decl)
2770 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2771 /* We already checked these parameters when the template was
2772 declared, so there's no need to do it again now. This function
2773 was defined in class scope, but we're processing it's body now
2774 that the class is complete. */
2779 If a template-parameter has a default template-argument, all
2780 subsequent template-parameters shall have a default
2781 template-argument supplied. */
2782 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2784 tree inner_parms = TREE_VALUE (parm_level);
2785 int ntparms = TREE_VEC_LENGTH (inner_parms);
2786 int seen_def_arg_p = 0;
2789 for (i = 0; i < ntparms; ++i)
2791 tree parm = TREE_VEC_ELT (inner_parms, i);
2792 if (TREE_PURPOSE (parm))
2794 else if (seen_def_arg_p)
2796 error ("no default argument for %qD", TREE_VALUE (parm));
2797 /* For better subsequent error-recovery, we indicate that
2798 there should have been a default argument. */
2799 TREE_PURPOSE (parm) = error_mark_node;
2804 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2805 /* For an ordinary class template, default template arguments are
2806 allowed at the innermost level, e.g.:
2807 template <class T = int>
2809 but, in a partial specialization, they're not allowed even
2810 there, as we have in [temp.class.spec]:
2812 The template parameter list of a specialization shall not
2813 contain default template argument values.
2815 So, for a partial specialization, or for a function template,
2816 we look at all of them. */
2819 /* But, for a primary class template that is not a partial
2820 specialization we look at all template parameters except the
2822 parms = TREE_CHAIN (parms);
2824 /* Figure out what error message to issue. */
2825 if (TREE_CODE (decl) == FUNCTION_DECL)
2826 msg = "default template arguments may not be used in function templates";
2827 else if (is_partial)
2828 msg = "default template arguments may not be used in partial specializations";
2830 msg = "default argument for template parameter for class enclosing %qD";
2832 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2833 /* If we're inside a class definition, there's no need to
2834 examine the parameters to the class itself. On the one
2835 hand, they will be checked when the class is defined, and,
2836 on the other, default arguments are valid in things like:
2837 template <class T = double>
2838 struct S { template <class U> void f(U); };
2839 Here the default argument for `S' has no bearing on the
2840 declaration of `f'. */
2841 last_level_to_check = template_class_depth (current_class_type) + 1;
2843 /* Check everything. */
2844 last_level_to_check = 0;
2846 for (parm_level = parms;
2847 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2848 parm_level = TREE_CHAIN (parm_level))
2850 tree inner_parms = TREE_VALUE (parm_level);
2854 ntparms = TREE_VEC_LENGTH (inner_parms);
2855 for (i = 0; i < ntparms; ++i)
2856 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2864 /* Clear out the default argument so that we are not
2866 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2869 /* At this point, if we're still interested in issuing messages,
2870 they must apply to classes surrounding the object declared. */
2872 msg = "default argument for template parameter for class enclosing %qD";
2876 /* Worker for push_template_decl_real, called via
2877 for_each_template_parm. DATA is really an int, indicating the
2878 level of the parameters we are interested in. If T is a template
2879 parameter of that level, return nonzero. */
2882 template_parm_this_level_p (tree t, void* data)
2884 int this_level = *(int *)data;
2887 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2888 level = TEMPLATE_PARM_LEVEL (t);
2890 level = TEMPLATE_TYPE_LEVEL (t);
2891 return level == this_level;
2894 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2895 parameters given by current_template_args, or reuses a
2896 previously existing one, if appropriate. Returns the DECL, or an
2897 equivalent one, if it is replaced via a call to duplicate_decls.
2899 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2902 push_template_decl_real (tree decl, int is_friend)
2910 int new_template_p = 0;
2911 /* True if the template is a member template, in the sense of
2913 bool member_template_p = false;
2915 if (decl == error_mark_node)
2918 /* See if this is a partial specialization. */
2919 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2920 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2921 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2923 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2926 /* For a friend, we want the context of the friend function, not
2927 the type of which it is a friend. */
2928 ctx = DECL_CONTEXT (decl);
2929 else if (CP_DECL_CONTEXT (decl)
2930 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2931 /* In the case of a virtual function, we want the class in which
2933 ctx = CP_DECL_CONTEXT (decl);
2935 /* Otherwise, if we're currently defining some class, the DECL
2936 is assumed to be a member of the class. */
2937 ctx = current_scope ();
2939 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2942 if (!DECL_CONTEXT (decl))
2943 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2945 /* See if this is a primary template. */
2946 primary = template_parm_scope_p ();
2950 if (DECL_CLASS_SCOPE_P (decl))
2951 member_template_p = true;
2952 if (current_lang_name == lang_name_c)
2953 error ("template with C linkage");
2954 else if (TREE_CODE (decl) == TYPE_DECL
2955 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2956 error ("template class without a name");
2957 else if (TREE_CODE (decl) == FUNCTION_DECL)
2959 if (DECL_DESTRUCTOR_P (decl))
2963 A destructor shall not be a member template. */
2964 error ("destructor %qD declared as member template", decl);
2965 return error_mark_node;
2967 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2968 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2969 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2970 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2971 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2972 == void_list_node)))
2974 /* [basic.stc.dynamic.allocation]
2976 An allocation function can be a function
2977 template. ... Template allocation functions shall
2978 have two or more parameters. */
2979 error ("invalid template declaration of %qD", decl);
2983 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2984 && CLASS_TYPE_P (TREE_TYPE (decl)))
2985 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx)))
2989 error ("template declaration of %q#D", decl);
2990 return error_mark_node;
2994 /* Check to see that the rules regarding the use of default
2995 arguments are not being violated. */
2996 check_default_tmpl_args (decl, current_template_parms,
2997 primary, is_partial);
3000 return process_partial_specialization (decl);
3002 args = current_template_args ();
3005 || TREE_CODE (ctx) == FUNCTION_DECL
3006 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3007 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3009 if (DECL_LANG_SPECIFIC (decl)
3010 && DECL_TEMPLATE_INFO (decl)
3011 && DECL_TI_TEMPLATE (decl))
3012 tmpl = DECL_TI_TEMPLATE (decl);
3013 /* If DECL is a TYPE_DECL for a class-template, then there won't
3014 be DECL_LANG_SPECIFIC. The information equivalent to
3015 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3016 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3017 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3018 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3020 /* Since a template declaration already existed for this
3021 class-type, we must be redeclaring it here. Make sure
3022 that the redeclaration is valid. */
3023 redeclare_class_template (TREE_TYPE (decl),
3024 current_template_parms);
3025 /* We don't need to create a new TEMPLATE_DECL; just use the
3026 one we already had. */
3027 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3031 tmpl = build_template_decl (decl, current_template_parms,
3035 if (DECL_LANG_SPECIFIC (decl)
3036 && DECL_TEMPLATE_SPECIALIZATION (decl))
3038 /* A specialization of a member template of a template
3040 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3041 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3042 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3048 tree a, t, current, parms;
3051 if (TREE_CODE (decl) == TYPE_DECL)
3053 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3054 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3055 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3056 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3057 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3060 error ("%qD does not declare a template type", decl);
3064 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3066 error ("template definition of non-template %q#D", decl);
3070 tmpl = DECL_TI_TEMPLATE (decl);
3072 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3073 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3074 && DECL_TEMPLATE_SPECIALIZATION (decl)
3075 && DECL_MEMBER_TEMPLATE_P (tmpl))
3079 /* The declaration is a specialization of a member
3080 template, declared outside the class. Therefore, the
3081 innermost template arguments will be NULL, so we
3082 replace them with the arguments determined by the
3083 earlier call to check_explicit_specialization. */
3084 args = DECL_TI_ARGS (decl);
3087 = build_template_decl (decl, current_template_parms,
3089 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3090 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3091 DECL_TI_TEMPLATE (decl) = new_tmpl;
3092 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3093 DECL_TEMPLATE_INFO (new_tmpl)
3094 = tree_cons (tmpl, args, NULL_TREE);
3096 register_specialization (new_tmpl,
3097 most_general_template (tmpl),
3102 /* Make sure the template headers we got make sense. */
3104 parms = DECL_TEMPLATE_PARMS (tmpl);
3105 i = TMPL_PARMS_DEPTH (parms);
3106 if (TMPL_ARGS_DEPTH (args) != i)
3108 error ("expected %d levels of template parms for %q#D, got %d",
3109 i, decl, TMPL_ARGS_DEPTH (args));
3112 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3114 a = TMPL_ARGS_LEVEL (args, i);
3115 t = INNERMOST_TEMPLATE_PARMS (parms);
3117 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3119 if (current == decl)
3120 error ("got %d template parameters for %q#D",
3121 TREE_VEC_LENGTH (a), decl);
3123 error ("got %d template parameters for %q#T",
3124 TREE_VEC_LENGTH (a), current);
3125 error (" but %d required", TREE_VEC_LENGTH (t));
3128 /* Perhaps we should also check that the parms are used in the
3129 appropriate qualifying scopes in the declarator? */
3131 if (current == decl)
3134 current = TYPE_CONTEXT (current);
3138 DECL_TEMPLATE_RESULT (tmpl) = decl;
3139 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3141 /* Push template declarations for global functions and types. Note
3142 that we do not try to push a global template friend declared in a
3143 template class; such a thing may well depend on the template
3144 parameters of the class. */
3145 if (new_template_p && !ctx
3146 && !(is_friend && template_class_depth (current_class_type) > 0))
3148 tmpl = pushdecl_namespace_level (tmpl);
3149 if (tmpl == error_mark_node)
3150 return error_mark_node;
3155 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3156 if (DECL_CONV_FN_P (tmpl))
3158 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3160 /* It is a conversion operator. See if the type converted to
3161 depends on innermost template operands. */
3163 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3165 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3169 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3170 back to its most general template. If TMPL is a specialization,
3171 ARGS may only have the innermost set of arguments. Add the missing
3172 argument levels if necessary. */
3173 if (DECL_TEMPLATE_INFO (tmpl))
3174 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3176 info = tree_cons (tmpl, args, NULL_TREE);
3178 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3180 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3181 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3182 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3183 /* Don't change the name if we've already set it up. */
3184 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3185 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3187 else if (DECL_LANG_SPECIFIC (decl))
3188 DECL_TEMPLATE_INFO (decl) = info;
3190 return DECL_TEMPLATE_RESULT (tmpl);
3194 push_template_decl (tree decl)
3196 return push_template_decl_real (decl, 0);
3199 /* Called when a class template TYPE is redeclared with the indicated
3200 template PARMS, e.g.:
3202 template <class T> struct S;
3203 template <class T> struct S {}; */
3206 redeclare_class_template (tree type, tree parms)
3212 if (!TYPE_TEMPLATE_INFO (type))
3214 error ("%qT is not a template type", type);
3218 tmpl = TYPE_TI_TEMPLATE (type);
3219 if (!PRIMARY_TEMPLATE_P (tmpl))
3220 /* The type is nested in some template class. Nothing to worry
3221 about here; there are no new template parameters for the nested
3225 parms = INNERMOST_TEMPLATE_PARMS (parms);
3226 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3228 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3230 cp_error_at ("previous declaration %qD", tmpl);
3231 error ("used %d template parameter%s instead of %d",
3232 TREE_VEC_LENGTH (tmpl_parms),
3233 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
3234 TREE_VEC_LENGTH (parms));
3238 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3240 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3241 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3242 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3243 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3245 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3247 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3248 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3249 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3251 cp_error_at ("template parameter %q#D", tmpl_parm);
3252 error ("redeclared here as %q#D", parm);
3256 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3258 /* We have in [temp.param]:
3260 A template-parameter may not be given default arguments
3261 by two different declarations in the same scope. */
3262 error ("redefinition of default argument for %q#D", parm);
3263 error ("%J original definition appeared here", tmpl_parm);
3267 if (parm_default != NULL_TREE)
3268 /* Update the previous template parameters (which are the ones
3269 that will really count) with the new default value. */
3270 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3271 else if (tmpl_default != NULL_TREE)
3272 /* Update the new parameters, too; they'll be used as the
3273 parameters for any members. */
3274 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3278 /* Simplify EXPR if it is a non-dependent expression. Returns the
3279 (possibly simplified) expression. */
3282 fold_non_dependent_expr (tree expr)
3284 /* If we're in a template, but EXPR isn't value dependent, simplify
3285 it. We're supposed to treat:
3287 template <typename T> void f(T[1 + 1]);
3288 template <typename T> void f(T[2]);
3290 as two declarations of the same function, for example. */
3291 if (processing_template_decl
3292 && !type_dependent_expression_p (expr)
3293 && !value_dependent_expression_p (expr))
3295 HOST_WIDE_INT saved_processing_template_decl;
3297 saved_processing_template_decl = processing_template_decl;
3298 processing_template_decl = 0;
3299 expr = tsubst_copy_and_build (expr,
3302 /*in_decl=*/NULL_TREE,
3303 /*function_p=*/false);
3304 processing_template_decl = saved_processing_template_decl;
3309 /* EXPR is an expression which is used in a constant-expression context.
3310 For instance, it could be a VAR_DECL with a constant initializer.
3311 Extract the innest constant expression.
3313 This is basically a more powerful version of decl_constant_value, which
3314 can be used also in templates where initializers can maintain a
3315 syntactic rather than semantic form (even if they are non-dependent, for
3316 access-checking purposes). */
3319 fold_decl_constant_value (tree expr)
3323 tree const_expr = decl_constant_value (expr);
3324 /* In a template, the initializer for a VAR_DECL may not be
3325 marked as TREE_CONSTANT, in which case decl_constant_value
3326 will not return the initializer. Handle that special case
3328 if (expr == const_expr
3329 && TREE_CODE (expr) == VAR_DECL
3330 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (expr)
3331 && CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (expr))
3332 /* DECL_INITIAL can be NULL if we are processing a
3333 variable initialized to an expression involving itself.
3334 We know it is initialized to a constant -- but not what
3336 && DECL_INITIAL (expr))
3337 const_expr = DECL_INITIAL (expr);
3338 if (expr == const_expr)
3340 expr = fold_non_dependent_expr (const_expr);
3346 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3347 must be a function or a pointer-to-function type, as specified
3348 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3349 and check that the resulting function has external linkage. */
3352 convert_nontype_argument_function (tree type, tree expr)
3357 fn = instantiate_type (type, fns, tf_none);
3358 if (fn == error_mark_node)
3359 return error_mark_node;
3362 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3363 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3365 /* [temp.arg.nontype]/1
3367 A template-argument for a non-type, non-template template-parameter
3370 -- the address of an object or function with external linkage. */
3371 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3373 error ("%qE is not a valid template argument for type %qT "
3374 "because function %qD has not external linkage",
3375 expr, type, fn_no_ptr);
3382 /* Attempt to convert the non-type template parameter EXPR to the
3383 indicated TYPE. If the conversion is successful, return the
3384 converted value. If the conversion is unsuccessful, return
3385 NULL_TREE if we issued an error message, or error_mark_node if we
3386 did not. We issue error messages for out-and-out bad template
3387 parameters, but not simply because the conversion failed, since we
3388 might be just trying to do argument deduction. Both TYPE and EXPR
3389 must be non-dependent.
3391 The conversion follows the special rules described in
3392 [temp.arg.nontype], and it is much more strict than an implicit
3395 This function is called twice for each template argument (see
3396 lookup_template_class for a more accurate description of this
3397 problem). This means that we need to handle expressions which
3398 are not valid in a C++ source, but can be created from the
3399 first call (for instance, casts to perform conversions). These
3400 hacks can go away after we fix the double coercion problem. */
3403 convert_nontype_argument (tree type, tree expr)
3407 /* Detect immediately string literals as invalid non-type argument.
3408 This special-case is not needed for correctness (we would easily
3409 catch this later), but only to provide better diagnostic for this
3410 common user mistake. As suggested by DR 100, we do not mention
3411 linkage issues in the diagnostic as this is not the point. */
3412 if (TREE_CODE (expr) == STRING_CST)
3414 error ("%qE is not a valid template argument for type %qT "
3415 "because string literals can never be used in this context",
3420 /* If we are in a template, EXPR may be non-dependent, but still
3421 have a syntactic, rather than semantic, form. For example, EXPR
3422 might be a SCOPE_REF, rather than the VAR_DECL to which the
3423 SCOPE_REF refers. Preserving the qualifying scope is necessary
3424 so that access checking can be performed when the template is
3425 instantiated -- but here we need the resolved form so that we can
3426 convert the argument. */
3427 expr = fold_non_dependent_expr (expr);
3428 expr_type = TREE_TYPE (expr);
3430 /* HACK: Due to double coercion, we can get a
3431 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3432 which is the tree that we built on the first call (see
3433 below when coercing to reference to object or to reference to
3434 function). We just strip everything and get to the arg.
3435 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3437 if (TREE_CODE (expr) == NOP_EXPR)
3439 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3441 /* ??? Maybe we could use convert_from_reference here, but we
3442 would need to relax its constraints because the NOP_EXPR
3443 could actually change the type to something more cv-qualified,
3444 and this is not folded by convert_from_reference. */
3445 tree addr = TREE_OPERAND (expr, 0);
3446 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3447 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3448 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3449 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3450 (TREE_TYPE (expr_type),
3451 TREE_TYPE (TREE_TYPE (addr))));
3453 expr = TREE_OPERAND (addr, 0);
3454 expr_type = TREE_TYPE (expr);
3457 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3458 parameter is a pointer to object, through decay and
3459 qualification conversion. Let's strip everything. */
3460 else if (TYPE_PTROBV_P (type))
3463 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3464 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3465 /* Skip the ADDR_EXPR only if it is part of the decay for
3466 an array. Otherwise, it is part of the original argument
3467 in the source code. */
3468 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3469 expr = TREE_OPERAND (expr, 0);
3470 expr_type = TREE_TYPE (expr);
3474 /* [temp.arg.nontype]/5, bullet 1
3476 For a non-type template-parameter of integral or enumeration type,
3477 integral promotions (_conv.prom_) and integral conversions
3478 (_conv.integral_) are applied. */
3479 if (INTEGRAL_TYPE_P (type))
3481 if (!INTEGRAL_TYPE_P (expr_type))
3482 return error_mark_node;
3484 expr = fold_decl_constant_value (expr);
3485 /* Notice that there are constant expressions like '4 % 0' which
3486 do not fold into integer constants. */
3487 if (TREE_CODE (expr) != INTEGER_CST)
3489 error ("%qE is not a valid template argument for type %qT "
3490 "because it is a non-constant expression", expr, type);
3494 /* At this point, an implicit conversion does what we want,
3495 because we already know that the expression is of integral
3497 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3498 if (expr == error_mark_node)
3499 return error_mark_node;
3501 /* Conversion was allowed: fold it to a bare integer constant. */
3504 /* [temp.arg.nontype]/5, bullet 2
3506 For a non-type template-parameter of type pointer to object,
3507 qualification conversions (_conv.qual_) and the array-to-pointer
3508 conversion (_conv.array_) are applied. */
3509 else if (TYPE_PTROBV_P (type))
3511 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3513 A template-argument for a non-type, non-template template-parameter
3514 shall be one of: [...]
3516 -- the name of a non-type template-parameter;
3517 -- the address of an object or function with external linkage, [...]
3518 expressed as "& id-expression" where the & is optional if the name
3519 refers to a function or array, or if the corresponding
3520 template-parameter is a reference.
3522 Here, we do not care about functions, as they are invalid anyway
3523 for a parameter of type pointer-to-object. */
3524 bool constant_address_p =
3525 (TREE_CODE (expr) == ADDR_EXPR
3526 || TREE_CODE (expr_type) == ARRAY_TYPE
3527 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3529 expr = decay_conversion (expr);
3530 if (expr == error_mark_node)
3531 return error_mark_node;
3533 expr = perform_qualification_conversions (type, expr);
3534 if (expr == error_mark_node)
3535 return error_mark_node;
3537 if (!constant_address_p)
3539 error ("%qE is not a valid template argument for type %qT "
3540 "because it is not a constant pointer", expr, type);
3544 /* [temp.arg.nontype]/5, bullet 3
3546 For a non-type template-parameter of type reference to object, no
3547 conversions apply. The type referred to by the reference may be more
3548 cv-qualified than the (otherwise identical) type of the
3549 template-argument. The template-parameter is bound directly to the
3550 template-argument, which must be an lvalue. */
3551 else if (TYPE_REF_OBJ_P (type))
3553 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3555 return error_mark_node;
3557 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3559 error ("%qE is not a valid template argument for type %qT "
3560 "because of conflicts in cv-qualification", expr, type);
3564 if (!real_lvalue_p (expr))
3566 error ("%qE is not a valid template argument for type %qT "
3567 "because it is not a lvalue", expr, type);
3571 /* [temp.arg.nontype]/1
3573 A template-argument for a non-type, non-template template-parameter
3574 shall be one of: [...]
3576 -- the address of an object or function with external linkage. */
3577 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3579 error ("%qE is not a valid template argument for type %qT "
3580 "because object %qD has not external linkage",
3585 expr = build_nop (type, build_address (expr));
3587 /* [temp.arg.nontype]/5, bullet 4
3589 For a non-type template-parameter of type pointer to function, only
3590 the function-to-pointer conversion (_conv.func_) is applied. If the
3591 template-argument represents a set of overloaded functions (or a
3592 pointer to such), the matching function is selected from the set
3594 else if (TYPE_PTRFN_P (type))
3596 /* If the argument is a template-id, we might not have enough
3597 context information to decay the pointer.
3598 ??? Why static5.C requires decay and subst1.C works fine
3600 if (!type_unknown_p (expr_type))
3602 expr = decay_conversion (expr);
3603 if (expr == error_mark_node)
3604 return error_mark_node;
3607 expr = convert_nontype_argument_function (type, expr);
3608 if (!expr || expr == error_mark_node)
3611 /* [temp.arg.nontype]/5, bullet 5
3613 For a non-type template-parameter of type reference to function, no
3614 conversions apply. If the template-argument represents a set of
3615 overloaded functions, the matching function is selected from the set
3617 else if (TYPE_REFFN_P (type))
3619 if (TREE_CODE (expr) == ADDR_EXPR)
3621 error ("%qE is not a valid template argument for type %qT "
3622 "because it is a pointer", expr, type);
3623 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3627 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3628 if (!expr || expr == error_mark_node)
3631 expr = build_nop(type, build_address (expr));
3633 /* [temp.arg.nontype]/5, bullet 6
3635 For a non-type template-parameter of type pointer to member function,
3636 no conversions apply. If the template-argument represents a set of
3637 overloaded member functions, the matching member function is selected
3638 from the set (_over.over_). */
3639 else if (TYPE_PTRMEMFUNC_P (type))
3641 expr = instantiate_type (type, expr, tf_none);
3642 if (expr == error_mark_node)
3643 return error_mark_node;
3645 /* There is no way to disable standard conversions in
3646 resolve_address_of_overloaded_function (called by
3647 instantiate_type). It is possible that the call succeeded by
3648 converting &B::I to &D::I (where B is a base of D), so we need
3649 to reject this conversion here.
3651 Actually, even if there was a way to disable standard conversions,
3652 it would still be better to reject them here so that we can
3653 provide a superior diagnostic. */
3654 if (!same_type_p (TREE_TYPE (expr), type))
3656 /* Make sure we are just one standard conversion off. */
3657 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3658 error ("%qE is not a valid template argument for type %qT "
3659 "because it is of type %qT", expr, type,
3661 inform ("standard conversions are not allowed in this context");
3665 /* [temp.arg.nontype]/5, bullet 7
3667 For a non-type template-parameter of type pointer to data member,
3668 qualification conversions (_conv.qual_) are applied. */
3669 else if (TYPE_PTRMEM_P (type))
3671 expr = perform_qualification_conversions (type, expr);
3672 if (expr == error_mark_node)
3675 /* A template non-type parameter must be one of the above. */
3679 /* Sanity check: did we actually convert the argument to the
3681 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3686 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3687 template template parameters. Both PARM_PARMS and ARG_PARMS are
3688 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3691 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3692 the case, then extra parameters must have default arguments.
3694 Consider the example:
3695 template <class T, class Allocator = allocator> class vector;
3696 template<template <class U> class TT> class C;
3698 C<vector> is a valid instantiation. PARM_PARMS for the above code
3699 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3700 T and Allocator) and OUTER_ARGS contains the argument that is used to
3701 substitute the TT parameter. */
3704 coerce_template_template_parms (tree parm_parms,
3706 tsubst_flags_t complain,
3710 int nparms, nargs, i;
3713 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3714 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3716 nparms = TREE_VEC_LENGTH (parm_parms);
3717 nargs = TREE_VEC_LENGTH (arg_parms);
3719 /* The rule here is opposite of coerce_template_parms. */
3722 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3725 for (i = 0; i < nparms; ++i)
3727 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3728 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3730 if (arg == NULL_TREE || arg == error_mark_node
3731 || parm == NULL_TREE || parm == error_mark_node)
3734 if (TREE_CODE (arg) != TREE_CODE (parm))
3737 switch (TREE_CODE (parm))
3743 /* We encounter instantiations of templates like
3744 template <template <template <class> class> class TT>
3747 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3748 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3750 if (!coerce_template_template_parms
3751 (parmparm, argparm, complain, in_decl, outer_args))
3757 /* The tsubst call is used to handle cases such as
3759 template <int> class C {};
3760 template <class T, template <T> class TT> class D {};
3763 i.e. the parameter list of TT depends on earlier parameters. */
3764 if (!dependent_type_p (TREE_TYPE (arg))
3766 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3778 /* Convert the indicated template ARG as necessary to match the
3779 indicated template PARM. Returns the converted ARG, or
3780 error_mark_node if the conversion was unsuccessful. Error and
3781 warning messages are issued under control of COMPLAIN. This
3782 conversion is for the Ith parameter in the parameter list. ARGS is
3783 the full set of template arguments deduced so far. */
3786 convert_template_argument (tree parm,
3789 tsubst_flags_t complain,
3795 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3797 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3799 if (TREE_CODE (arg) == TREE_LIST
3800 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3802 /* The template argument was the name of some
3803 member function. That's usually
3804 invalid, but static members are OK. In any
3805 case, grab the underlying fields/functions
3806 and issue an error later if required. */
3807 arg = TREE_VALUE (arg);
3808 TREE_TYPE (arg) = unknown_type_node;
3811 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3812 requires_type = (TREE_CODE (parm) == TYPE_DECL
3813 || requires_tmpl_type);
3815 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3816 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3817 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3818 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3821 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3822 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3823 arg = TYPE_STUB_DECL (arg);
3825 is_type = TYPE_P (arg) || is_tmpl_type;
3827 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3828 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3830 pedwarn ("to refer to a type member of a template parameter, "
3831 "use %<typename %E%>", arg);
3833 arg = make_typename_type (TREE_OPERAND (arg, 0),
3834 TREE_OPERAND (arg, 1),
3836 complain & tf_error);
3839 if (is_type != requires_type)
3843 if (complain & tf_error)
3845 error ("type/value mismatch at argument %d in template "
3846 "parameter list for %qD",
3849 error (" expected a constant of type %qT, got %qT",
3851 (is_tmpl_type ? DECL_NAME (arg) : arg));
3852 else if (requires_tmpl_type)
3853 error (" expected a class template, got %qE", arg);
3855 error (" expected a type, got %qE", arg);
3858 return error_mark_node;
3860 if (is_tmpl_type ^ requires_tmpl_type)
3862 if (in_decl && (complain & tf_error))
3864 error ("type/value mismatch at argument %d in template "
3865 "parameter list for %qD",
3868 error (" expected a type, got %qT", DECL_NAME (arg));
3870 error (" expected a class template, got %qT", arg);
3872 return error_mark_node;
3877 if (requires_tmpl_type)
3879 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3880 /* The number of argument required is not known yet.
3881 Just accept it for now. */
3882 val = TREE_TYPE (arg);
3885 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3886 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3888 if (coerce_template_template_parms (parmparm, argparm,
3894 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3896 if (val != error_mark_node
3897 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3898 val = TREE_TYPE (val);
3902 if (in_decl && (complain & tf_error))
3904 error ("type/value mismatch at argument %d in "
3905 "template parameter list for %qD",
3907 error (" expected a template of type %qD, got %qD",
3911 val = error_mark_node;
3920 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3922 if (invalid_nontype_parm_type_p (t, complain))
3923 return error_mark_node;
3925 if (!uses_template_parms (arg) && !uses_template_parms (t))
3926 /* We used to call digest_init here. However, digest_init
3927 will report errors, which we don't want when complain
3928 is zero. More importantly, digest_init will try too
3929 hard to convert things: for example, `0' should not be
3930 converted to pointer type at this point according to
3931 the standard. Accepting this is not merely an
3932 extension, since deciding whether or not these
3933 conversions can occur is part of determining which
3934 function template to call, or whether a given explicit
3935 argument specification is valid. */
3936 val = convert_nontype_argument (t, arg);
3940 if (val == NULL_TREE)
3941 val = error_mark_node;
3942 else if (val == error_mark_node && (complain & tf_error))
3943 error ("could not convert template argument %qE to %qT", arg, t);
3949 /* Convert all template arguments to their appropriate types, and
3950 return a vector containing the innermost resulting template
3951 arguments. If any error occurs, return error_mark_node. Error and
3952 warning messages are issued under control of COMPLAIN.
3954 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3955 provided in ARGLIST, or else trailing parameters must have default
3956 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3957 deduction for any unspecified trailing arguments. */
3960 coerce_template_parms (tree parms,
3963 tsubst_flags_t complain,
3964 int require_all_arguments)
3966 int nparms, nargs, i, lost = 0;
3969 tree new_inner_args;
3971 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3972 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3973 nparms = TREE_VEC_LENGTH (parms);
3977 && require_all_arguments
3978 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3980 if (complain & tf_error)
3982 error ("wrong number of template arguments (%d, should be %d)",
3986 cp_error_at ("provided for %qD", in_decl);
3989 return error_mark_node;
3992 new_inner_args = make_tree_vec (nparms);
3993 new_args = add_outermost_template_args (args, new_inner_args);
3994 for (i = 0; i < nparms; i++)
3999 /* Get the Ith template parameter. */
4000 parm = TREE_VEC_ELT (parms, i);
4002 /* Calculate the Ith argument. */
4004 arg = TREE_VEC_ELT (inner_args, i);
4005 else if (require_all_arguments)
4006 /* There must be a default arg in this case. */
4007 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4013 if (arg == error_mark_node)
4015 if (complain & tf_error)
4016 error ("template argument %d is invalid", i + 1);
4019 arg = convert_template_argument (TREE_VALUE (parm),
4020 arg, new_args, complain, i,
4023 if (arg == error_mark_node)
4025 TREE_VEC_ELT (new_inner_args, i) = arg;
4029 return error_mark_node;
4031 return new_inner_args;
4034 /* Returns 1 if template args OT and NT are equivalent. */
4037 template_args_equal (tree ot, tree nt)
4042 if (TREE_CODE (nt) == TREE_VEC)
4043 /* For member templates */
4044 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4045 else if (TYPE_P (nt))
4046 return TYPE_P (ot) && same_type_p (ot, nt);
4047 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4050 return cp_tree_equal (ot, nt);
4053 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4054 of template arguments. Returns 0 otherwise. */
4057 comp_template_args (tree oldargs, tree newargs)
4061 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4064 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4066 tree nt = TREE_VEC_ELT (newargs, i);
4067 tree ot = TREE_VEC_ELT (oldargs, i);
4069 if (! template_args_equal (ot, nt))
4075 /* Given class template name and parameter list, produce a user-friendly name
4076 for the instantiation. */
4079 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4081 static struct obstack scratch_obstack;
4082 static char *scratch_firstobj;
4085 if (!scratch_firstobj)
4086 gcc_obstack_init (&scratch_obstack);
4088 obstack_free (&scratch_obstack, scratch_firstobj);
4089 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4091 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4092 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4096 nparms = TREE_VEC_LENGTH (parms);
4097 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4098 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4099 for (i = 0; i < nparms; i++)
4101 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4102 tree arg = TREE_VEC_ELT (arglist, i);
4107 if (TREE_CODE (parm) == TYPE_DECL)
4109 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4112 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4114 if (TREE_CODE (arg) == TEMPLATE_DECL)
4116 /* Already substituted with real template. Just output
4117 the template name here */
4118 tree context = DECL_CONTEXT (arg);
4121 /* The template may be defined in a namespace, or
4122 may be a member template. */
4123 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4124 || CLASS_TYPE_P (context));
4125 cat (decl_as_string (DECL_CONTEXT (arg),
4126 TFF_PLAIN_IDENTIFIER));
4129 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4132 /* Output the parameter declaration. */
4133 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4137 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4139 /* No need to check arglist against parmlist here; we did that
4140 in coerce_template_parms, called from lookup_template_class. */
4141 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4144 char *bufp = obstack_next_free (&scratch_obstack);
4146 while (bufp[offset - 1] == ' ')
4148 obstack_blank_fast (&scratch_obstack, offset);
4150 /* B<C<char> >, not B<C<char>> */
4151 if (bufp[offset - 1] == '>')
4156 return (char *) obstack_base (&scratch_obstack);
4160 classtype_mangled_name (tree t)
4162 if (CLASSTYPE_TEMPLATE_INFO (t)
4163 /* Specializations have already had their names set up in
4164 lookup_template_class. */
4165 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4167 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4169 /* For non-primary templates, the template parameters are
4170 implicit from their surrounding context. */
4171 if (PRIMARY_TEMPLATE_P (tmpl))
4173 tree name = DECL_NAME (tmpl);
4174 char *mangled_name = mangle_class_name_for_template
4175 (IDENTIFIER_POINTER (name),
4176 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4177 CLASSTYPE_TI_ARGS (t));
4178 tree id = get_identifier (mangled_name);
4179 IDENTIFIER_TEMPLATE (id) = name;
4184 return TYPE_IDENTIFIER (t);
4188 add_pending_template (tree d)
4190 tree ti = (TYPE_P (d)
4191 ? CLASSTYPE_TEMPLATE_INFO (d)
4192 : DECL_TEMPLATE_INFO (d));
4196 if (TI_PENDING_TEMPLATE_FLAG (ti))
4199 /* We are called both from instantiate_decl, where we've already had a
4200 tinst_level pushed, and instantiate_template, where we haven't.
4202 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4205 push_tinst_level (d);
4207 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4208 if (last_pending_template)
4209 TREE_CHAIN (last_pending_template) = pt;
4211 pending_templates = pt;
4213 last_pending_template = pt;
4215 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4222 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4223 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4224 documentation for TEMPLATE_ID_EXPR. */
4227 lookup_template_function (tree fns, tree arglist)
4231 if (fns == error_mark_node || arglist == error_mark_node)
4232 return error_mark_node;
4234 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4235 if (fns == NULL_TREE
4236 || TREE_CODE (fns) == FUNCTION_DECL)
4238 error ("non-template used as template");
4239 return error_mark_node;
4242 gcc_assert (TREE_CODE (fns) == TEMPLATE_DECL
4243 || TREE_CODE (fns) == OVERLOAD
4245 || TREE_CODE (fns) == IDENTIFIER_NODE);
4247 if (BASELINK_P (fns))
4249 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4251 BASELINK_FUNCTIONS (fns),
4256 type = TREE_TYPE (fns);
4257 if (TREE_CODE (fns) == OVERLOAD || !type)
4258 type = unknown_type_node;
4260 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4263 /* Within the scope of a template class S<T>, the name S gets bound
4264 (in build_self_reference) to a TYPE_DECL for the class, not a
4265 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4266 or one of its enclosing classes, and that type is a template,
4267 return the associated TEMPLATE_DECL. Otherwise, the original
4268 DECL is returned. */
4271 maybe_get_template_decl_from_type_decl (tree decl)
4273 return (decl != NULL_TREE
4274 && TREE_CODE (decl) == TYPE_DECL
4275 && DECL_ARTIFICIAL (decl)
4276 && CLASS_TYPE_P (TREE_TYPE (decl))
4277 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4278 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4281 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4282 parameters, find the desired type.
4284 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4286 IN_DECL, if non-NULL, is the template declaration we are trying to
4289 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4290 the class we are looking up.
4292 Issue error and warning messages under control of COMPLAIN.
4294 If the template class is really a local class in a template
4295 function, then the FUNCTION_CONTEXT is the function in which it is
4298 ??? Note that this function is currently called *twice* for each
4299 template-id: the first time from the parser, while creating the
4300 incomplete type (finish_template_type), and the second type during the
4301 real instantiation (instantiate_template_class). This is surely something
4302 that we want to avoid. It also causes some problems with argument
4303 coercion (see convert_nontype_argument for more information on this). */
4306 lookup_template_class (tree d1,
4311 tsubst_flags_t complain)
4313 tree template = NULL_TREE, parmlist;
4316 timevar_push (TV_NAME_LOOKUP);
4318 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4320 tree value = innermost_non_namespace_value (d1);
4321 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4326 push_decl_namespace (context);
4327 template = lookup_name (d1, /*prefer_type=*/0);
4328 template = maybe_get_template_decl_from_type_decl (template);
4330 pop_decl_namespace ();
4333 context = DECL_CONTEXT (template);
4335 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4337 tree type = TREE_TYPE (d1);
4339 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4340 an implicit typename for the second A. Deal with it. */
4341 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4342 type = TREE_TYPE (type);
4344 if (CLASSTYPE_TEMPLATE_INFO (type))
4346 template = CLASSTYPE_TI_TEMPLATE (type);
4347 d1 = DECL_NAME (template);
4350 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4351 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4353 template = TYPE_TI_TEMPLATE (d1);
4354 d1 = DECL_NAME (template);
4356 else if (TREE_CODE (d1) == TEMPLATE_DECL
4357 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4360 d1 = DECL_NAME (template);
4361 context = DECL_CONTEXT (template);
4364 /* Issue an error message if we didn't find a template. */
4367 if (complain & tf_error)
4368 error ("%qT is not a template", d1);
4369 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4372 if (TREE_CODE (template) != TEMPLATE_DECL
4373 /* Make sure it's a user visible template, if it was named by
4375 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4376 && !PRIMARY_TEMPLATE_P (template)))
4378 if (complain & tf_error)
4380 error ("non-template type %qT used as a template", d1);
4382 cp_error_at ("for template declaration %qD", in_decl);
4384 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4387 complain &= ~tf_user;
4389 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4391 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4392 template arguments */
4397 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4399 /* Consider an example where a template template parameter declared as
4401 template <class T, class U = std::allocator<T> > class TT
4403 The template parameter level of T and U are one level larger than
4404 of TT. To proper process the default argument of U, say when an
4405 instantiation `TT<int>' is seen, we need to build the full
4406 arguments containing {int} as the innermost level. Outer levels,
4407 available when not appearing as default template argument, can be
4408 obtained from `current_template_args ()'.
4410 Suppose that TT is later substituted with std::vector. The above
4411 instantiation is `TT<int, std::allocator<T> >' with TT at
4412 level 1, and T at level 2, while the template arguments at level 1
4413 becomes {std::vector} and the inner level 2 is {int}. */
4415 if (current_template_parms)
4416 arglist = add_to_template_args (current_template_args (), arglist);
4418 arglist2 = coerce_template_parms (parmlist, arglist, template,
4419 complain, /*require_all_args=*/1);
4420 if (arglist2 == error_mark_node
4421 || (!uses_template_parms (arglist2)
4422 && check_instantiated_args (template, arglist2, complain)))
4423 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4425 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4426 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4430 tree template_type = TREE_TYPE (template);
4433 tree found = NULL_TREE;
4436 int is_partial_instantiation;
4438 gen_tmpl = most_general_template (template);
4439 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4440 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4441 arg_depth = TMPL_ARGS_DEPTH (arglist);
4443 if (arg_depth == 1 && parm_depth > 1)
4445 /* We've been given an incomplete set of template arguments.
4448 template <class T> struct S1 {
4449 template <class U> struct S2 {};
4450 template <class U> struct S2<U*> {};
4453 we will be called with an ARGLIST of `U*', but the
4454 TEMPLATE will be `template <class T> template
4455 <class U> struct S1<T>::S2'. We must fill in the missing
4458 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4460 arg_depth = TMPL_ARGS_DEPTH (arglist);
4463 /* Now we should have enough arguments. */
4464 gcc_assert (parm_depth == arg_depth);
4466 /* From here on, we're only interested in the most general
4468 template = gen_tmpl;
4470 /* Calculate the BOUND_ARGS. These will be the args that are
4471 actually tsubst'd into the definition to create the
4475 /* We have multiple levels of arguments to coerce, at once. */
4477 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4479 tree bound_args = make_tree_vec (parm_depth);
4481 for (i = saved_depth,
4482 t = DECL_TEMPLATE_PARMS (template);
4483 i > 0 && t != NULL_TREE;
4484 --i, t = TREE_CHAIN (t))
4486 tree a = coerce_template_parms (TREE_VALUE (t),
4488 complain, /*require_all_args=*/1);
4490 /* Don't process further if one of the levels fails. */
4491 if (a == error_mark_node)
4493 /* Restore the ARGLIST to its full size. */
4494 TREE_VEC_LENGTH (arglist) = saved_depth;
4495 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4498 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4500 /* We temporarily reduce the length of the ARGLIST so
4501 that coerce_template_parms will see only the arguments
4502 corresponding to the template parameters it is
4504 TREE_VEC_LENGTH (arglist)--;
4507 /* Restore the ARGLIST to its full size. */
4508 TREE_VEC_LENGTH (arglist) = saved_depth;
4510 arglist = bound_args;
4514 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4515 INNERMOST_TEMPLATE_ARGS (arglist),
4517 complain, /*require_all_args=*/1);
4519 if (arglist == error_mark_node)
4520 /* We were unable to bind the arguments. */
4521 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4523 /* In the scope of a template class, explicit references to the
4524 template class refer to the type of the template, not any
4525 instantiation of it. For example, in:
4527 template <class T> class C { void f(C<T>); }
4529 the `C<T>' is just the same as `C'. Outside of the
4530 class, however, such a reference is an instantiation. */
4531 if (comp_template_args (TYPE_TI_ARGS (template_type),
4534 found = template_type;
4536 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4540 for (ctx = current_class_type;
4541 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4543 ? TYPE_CONTEXT (ctx)
4544 : DECL_CONTEXT (ctx)))
4545 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4548 /* We're not in the scope of the class, so the
4549 TEMPLATE_TYPE is not the type we want after all. */
4555 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4557 /* If we already have this specialization, return it. */
4558 found = retrieve_specialization (template, arglist,
4559 /*class_specializations_p=*/false);
4561 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4563 /* This type is a "partial instantiation" if any of the template
4564 arguments still involve template parameters. Note that we set
4565 IS_PARTIAL_INSTANTIATION for partial specializations as
4567 is_partial_instantiation = uses_template_parms (arglist);
4569 /* If the deduced arguments are invalid, then the binding
4571 if (!is_partial_instantiation
4572 && check_instantiated_args (template,
4573 INNERMOST_TEMPLATE_ARGS (arglist),
4575 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4577 if (!is_partial_instantiation
4578 && !PRIMARY_TEMPLATE_P (template)
4579 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4581 found = xref_tag_from_type (TREE_TYPE (template),
4582 DECL_NAME (template),
4583 /*tag_scope=*/ts_global);
4584 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4587 context = tsubst (DECL_CONTEXT (template), arglist,
4590 context = global_namespace;
4592 /* Create the type. */
4593 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4595 if (!is_partial_instantiation)
4597 set_current_access_from_decl (TYPE_NAME (template_type));
4598 t = start_enum (TYPE_IDENTIFIER (template_type));
4601 /* We don't want to call start_enum for this type, since
4602 the values for the enumeration constants may involve
4603 template parameters. And, no one should be interested
4604 in the enumeration constants for such a type. */
4605 t = make_node (ENUMERAL_TYPE);
4609 t = make_aggr_type (TREE_CODE (template_type));
4610 CLASSTYPE_DECLARED_CLASS (t)
4611 = CLASSTYPE_DECLARED_CLASS (template_type);
4612 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4613 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4615 /* A local class. Make sure the decl gets registered properly. */
4616 if (context == current_function_decl)
4617 pushtag (DECL_NAME (template), t, 0);
4620 /* If we called start_enum or pushtag above, this information
4621 will already be set up. */
4624 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4626 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4627 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4628 TYPE_STUB_DECL (t) = type_decl;
4629 DECL_SOURCE_LOCATION (type_decl)
4630 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4633 type_decl = TYPE_NAME (t);
4635 TREE_PRIVATE (type_decl)
4636 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4637 TREE_PROTECTED (type_decl)
4638 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4640 /* Set up the template information. We have to figure out which
4641 template is the immediate parent if this is a full
4643 if (parm_depth == 1 || is_partial_instantiation
4644 || !PRIMARY_TEMPLATE_P (template))
4645 /* This case is easy; there are no member templates involved. */
4649 /* This is a full instantiation of a member template. Look
4650 for a partial instantiation of which this is an instance. */
4652 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4653 found; found = TREE_CHAIN (found))
4656 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4658 /* We only want partial instantiations, here, not
4659 specializations or full instantiations. */
4660 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4661 || !uses_template_parms (TREE_VALUE (found)))
4664 /* Temporarily reduce by one the number of levels in the
4665 ARGLIST and in FOUND so as to avoid comparing the
4666 last set of arguments. */
4667 TREE_VEC_LENGTH (arglist)--;
4668 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4670 /* See if the arguments match. If they do, then TMPL is
4671 the partial instantiation we want. */
4672 success = comp_template_args (TREE_PURPOSE (found), arglist);
4674 /* Restore the argument vectors to their full size. */
4675 TREE_VEC_LENGTH (arglist)++;
4676 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4687 /* There was no partial instantiation. This happens
4688 where C<T> is a member template of A<T> and it's used
4691 template <typename T> struct B { A<T>::C<int> m; };
4694 Create the partial instantiation.
4696 TREE_VEC_LENGTH (arglist)--;
4697 found = tsubst (template, arglist, complain, NULL_TREE);
4698 TREE_VEC_LENGTH (arglist)++;
4702 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4703 DECL_TEMPLATE_INSTANTIATIONS (template)
4704 = tree_cons (arglist, t,
4705 DECL_TEMPLATE_INSTANTIATIONS (template));
4707 if (TREE_CODE (t) == ENUMERAL_TYPE
4708 && !is_partial_instantiation)
4709 /* Now that the type has been registered on the instantiations
4710 list, we set up the enumerators. Because the enumeration
4711 constants may involve the enumeration type itself, we make
4712 sure to register the type first, and then create the
4713 constants. That way, doing tsubst_expr for the enumeration
4714 constants won't result in recursive calls here; we'll find
4715 the instantiation and exit above. */
4716 tsubst_enum (template_type, t, arglist);
4718 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4720 if (TREE_CODE (t) != ENUMERAL_TYPE)
4721 DECL_NAME (type_decl) = classtype_mangled_name (t);
4722 if (is_partial_instantiation)
4723 /* If the type makes use of template parameters, the
4724 code that generates debugging information will crash. */
4725 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4727 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4729 timevar_pop (TV_NAME_LOOKUP);
4736 struct pointer_set_t *visited;
4739 /* Called from for_each_template_parm via walk_tree. */
4742 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4745 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4746 tree_fn_t fn = pfd->fn;
4747 void *data = pfd->data;
4750 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4751 return error_mark_node;
4753 switch (TREE_CODE (t))
4756 if (TYPE_PTRMEMFUNC_P (t))
4762 if (!TYPE_TEMPLATE_INFO (t))
4764 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4765 fn, data, pfd->visited))
4766 return error_mark_node;
4770 /* Since we're not going to walk subtrees, we have to do this
4772 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4774 return error_mark_node;
4778 /* Check the return type. */
4779 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4780 return error_mark_node;
4782 /* Check the parameter types. Since default arguments are not
4783 instantiated until they are needed, the TYPE_ARG_TYPES may
4784 contain expressions that involve template parameters. But,
4785 no-one should be looking at them yet. And, once they're
4786 instantiated, they don't contain template parameters, so
4787 there's no point in looking at them then, either. */
4791 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4792 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4794 return error_mark_node;
4796 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4797 want walk_tree walking into them itself. */
4803 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4805 return error_mark_node;
4810 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4811 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4813 return error_mark_node;
4818 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4819 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4821 return error_mark_node;
4822 if (DECL_CONTEXT (t)
4823 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4825 return error_mark_node;
4828 case BOUND_TEMPLATE_TEMPLATE_PARM:
4829 /* Record template parameters such as `T' inside `TT<T>'. */
4830 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4831 return error_mark_node;
4834 case TEMPLATE_TEMPLATE_PARM:
4835 case TEMPLATE_TYPE_PARM:
4836 case TEMPLATE_PARM_INDEX:
4837 if (fn && (*fn)(t, data))
4838 return error_mark_node;
4840 return error_mark_node;
4844 /* A template template parameter is encountered. */
4845 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4846 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4847 return error_mark_node;
4849 /* Already substituted template template parameter */
4855 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4856 data, pfd->visited))
4857 return error_mark_node;
4861 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4862 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4863 (TREE_TYPE (t)), fn, data,
4865 return error_mark_node;
4870 /* If there's no type, then this thing must be some expression
4871 involving template parameters. */
4872 if (!fn && !TREE_TYPE (t))
4873 return error_mark_node;
4878 case REINTERPRET_CAST_EXPR:
4879 case CONST_CAST_EXPR:
4880 case STATIC_CAST_EXPR:
4881 case DYNAMIC_CAST_EXPR:
4885 case PSEUDO_DTOR_EXPR:
4887 return error_mark_node;
4891 /* If we do not handle this case specially, we end up walking
4892 the BINFO hierarchy, which is circular, and therefore
4893 confuses walk_tree. */
4895 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4897 return error_mark_node;
4904 /* We didn't find any template parameters we liked. */
4908 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4909 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4910 call FN with the parameter and the DATA.
4911 If FN returns nonzero, the iteration is terminated, and
4912 for_each_template_parm returns 1. Otherwise, the iteration
4913 continues. If FN never returns a nonzero value, the value
4914 returned by for_each_template_parm is 0. If FN is NULL, it is
4915 considered to be the function which always returns 1. */
4918 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4919 struct pointer_set_t *visited)
4921 struct pair_fn_data pfd;
4928 /* Walk the tree. (Conceptually, we would like to walk without
4929 duplicates, but for_each_template_parm_r recursively calls
4930 for_each_template_parm, so we would need to reorganize a fair
4931 bit to use walk_tree_without_duplicates, so we keep our own
4934 pfd.visited = visited;
4936 pfd.visited = pointer_set_create ();
4937 result = walk_tree (&t,
4938 for_each_template_parm_r,
4940 pfd.visited) != NULL_TREE;
4945 pointer_set_destroy (pfd.visited);
4952 /* Returns true if T depends on any template parameter. */
4955 uses_template_parms (tree t)
4958 int saved_processing_template_decl;
4960 saved_processing_template_decl = processing_template_decl;
4961 if (!saved_processing_template_decl)
4962 processing_template_decl = 1;
4964 dependent_p = dependent_type_p (t);
4965 else if (TREE_CODE (t) == TREE_VEC)
4966 dependent_p = any_dependent_template_arguments_p (t);
4967 else if (TREE_CODE (t) == TREE_LIST)
4968 dependent_p = (uses_template_parms (TREE_VALUE (t))
4969 || uses_template_parms (TREE_CHAIN (t)));
4972 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4973 || TREE_CODE (t) == OVERLOAD
4974 || TREE_CODE (t) == BASELINK
4975 || CONSTANT_CLASS_P (t))
4976 dependent_p = (type_dependent_expression_p (t)
4977 || value_dependent_expression_p (t));
4980 gcc_assert (t == error_mark_node);
4981 dependent_p = false;
4984 processing_template_decl = saved_processing_template_decl;
4989 /* Returns true if T depends on any template parameter with level LEVEL. */
4992 uses_template_parms_level (tree t, int level)
4994 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4997 static int tinst_depth;
4998 extern int max_tinst_depth;
4999 #ifdef GATHER_STATISTICS
5002 static int tinst_level_tick;
5003 static int last_template_error_tick;
5005 /* We're starting to instantiate D; record the template instantiation context
5006 for diagnostics and to restore it later. */
5009 push_tinst_level (tree d)
5013 if (tinst_depth >= max_tinst_depth)
5015 /* If the instantiation in question still has unbound template parms,
5016 we don't really care if we can't instantiate it, so just return.
5017 This happens with base instantiation for implicit `typename'. */
5018 if (uses_template_parms (d))
5021 last_template_error_tick = tinst_level_tick;
5022 error ("template instantiation depth exceeds maximum of %d (use "
5023 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5024 max_tinst_depth, d);
5026 print_instantiation_context ();
5031 new = make_tinst_level (d, input_location);
5032 TREE_CHAIN (new) = current_tinst_level;
5033 current_tinst_level = new;
5036 #ifdef GATHER_STATISTICS
5037 if (tinst_depth > depth_reached)
5038 depth_reached = tinst_depth;
5045 /* We're done instantiating this template; return to the instantiation
5049 pop_tinst_level (void)
5051 tree old = current_tinst_level;
5053 /* Restore the filename and line number stashed away when we started
5054 this instantiation. */
5055 input_location = TINST_LOCATION (old);
5056 current_tinst_level = TREE_CHAIN (old);
5061 /* We're instantiating a deferred template; restore the template
5062 instantiation context in which the instantiation was requested, which
5063 is one step out from LEVEL. */
5066 reopen_tinst_level (tree level)
5071 for (t = level; t; t = TREE_CHAIN (t))
5074 current_tinst_level = level;
5078 /* Return the outermost template instantiation context, for use with
5079 -falt-external-templates. */
5082 tinst_for_decl (void)
5084 tree p = current_tinst_level;
5087 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
5092 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5093 vector of template arguments, as for tsubst.
5095 Returns an appropriate tsubst'd friend declaration. */
5098 tsubst_friend_function (tree decl, tree args)
5102 if (TREE_CODE (decl) == FUNCTION_DECL
5103 && DECL_TEMPLATE_INSTANTIATION (decl)
5104 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5105 /* This was a friend declared with an explicit template
5106 argument list, e.g.:
5110 to indicate that f was a template instantiation, not a new
5111 function declaration. Now, we have to figure out what
5112 instantiation of what template. */
5114 tree template_id, arglist, fns;
5117 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5119 /* Friend functions are looked up in the containing namespace scope.
5120 We must enter that scope, to avoid finding member functions of the
5121 current cless with same name. */
5122 push_nested_namespace (ns);
5123 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5124 tf_error | tf_warning, NULL_TREE);
5125 pop_nested_namespace (ns);
5126 arglist = tsubst (DECL_TI_ARGS (decl), args,
5127 tf_error | tf_warning, NULL_TREE);
5128 template_id = lookup_template_function (fns, arglist);
5130 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5131 tmpl = determine_specialization (template_id, new_friend,
5133 /*need_member_template=*/0,
5134 TREE_VEC_LENGTH (args));
5135 return instantiate_template (tmpl, new_args, tf_error);
5138 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5140 /* The NEW_FRIEND will look like an instantiation, to the
5141 compiler, but is not an instantiation from the point of view of
5142 the language. For example, we might have had:
5144 template <class T> struct S {
5145 template <class U> friend void f(T, U);
5148 Then, in S<int>, template <class U> void f(int, U) is not an
5149 instantiation of anything. */
5150 if (new_friend == error_mark_node)
5151 return error_mark_node;
5153 DECL_USE_TEMPLATE (new_friend) = 0;
5154 if (TREE_CODE (decl) == TEMPLATE_DECL)
5156 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5157 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5158 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5161 /* The mangled name for the NEW_FRIEND is incorrect. The function
5162 is not a template instantiation and should not be mangled like
5163 one. Therefore, we forget the mangling here; we'll recompute it
5164 later if we need it. */
5165 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5167 SET_DECL_RTL (new_friend, NULL_RTX);
5168 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5171 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5174 tree new_friend_template_info;
5175 tree new_friend_result_template_info;
5177 int new_friend_is_defn;
5179 /* We must save some information from NEW_FRIEND before calling
5180 duplicate decls since that function will free NEW_FRIEND if
5182 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5183 new_friend_is_defn =
5184 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5185 (template_for_substitution (new_friend)))
5187 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5189 /* This declaration is a `primary' template. */
5190 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5192 new_friend_result_template_info
5193 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5196 new_friend_result_template_info = NULL_TREE;
5198 /* Inside pushdecl_namespace_level, we will push into the
5199 current namespace. However, the friend function should go
5200 into the namespace of the template. */
5201 ns = decl_namespace_context (new_friend);
5202 push_nested_namespace (ns);
5203 old_decl = pushdecl_namespace_level (new_friend);
5204 pop_nested_namespace (ns);
5206 if (old_decl != new_friend)
5208 /* This new friend declaration matched an existing
5209 declaration. For example, given:
5211 template <class T> void f(T);
5212 template <class U> class C {
5213 template <class T> friend void f(T) {}
5216 the friend declaration actually provides the definition
5217 of `f', once C has been instantiated for some type. So,
5218 old_decl will be the out-of-class template declaration,
5219 while new_friend is the in-class definition.
5221 But, if `f' was called before this point, the
5222 instantiation of `f' will have DECL_TI_ARGS corresponding
5223 to `T' but not to `U', references to which might appear
5224 in the definition of `f'. Previously, the most general
5225 template for an instantiation of `f' was the out-of-class
5226 version; now it is the in-class version. Therefore, we
5227 run through all specialization of `f', adding to their
5228 DECL_TI_ARGS appropriately. In particular, they need a
5229 new set of outer arguments, corresponding to the
5230 arguments for this class instantiation.
5232 The same situation can arise with something like this:
5235 template <class T> class C {
5239 when `C<int>' is instantiated. Now, `f(int)' is defined
5242 if (!new_friend_is_defn)
5243 /* On the other hand, if the in-class declaration does
5244 *not* provide a definition, then we don't want to alter
5245 existing definitions. We can just leave everything
5250 /* Overwrite whatever template info was there before, if
5251 any, with the new template information pertaining to
5253 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5255 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5256 reregister_specialization (new_friend,
5257 most_general_template (old_decl),
5262 tree new_friend_args;
5264 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5265 = new_friend_result_template_info;
5267 new_friend_args = TI_ARGS (new_friend_template_info);
5268 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5272 tree spec = TREE_VALUE (t);
5275 = add_outermost_template_args (new_friend_args,
5276 DECL_TI_ARGS (spec));
5279 /* Now, since specializations are always supposed to
5280 hang off of the most general template, we must move
5282 t = most_general_template (old_decl);
5285 DECL_TEMPLATE_SPECIALIZATIONS (t)
5286 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5287 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5288 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5293 /* The information from NEW_FRIEND has been merged into OLD_DECL
5294 by duplicate_decls. */
5295 new_friend = old_decl;
5300 tree context = DECL_CONTEXT (new_friend);
5304 template <class T> class C {
5305 template <class U> friend void C1<U>::f (); // case 1
5306 friend void C2<T>::f (); // case 2
5308 we only need to make sure CONTEXT is a complete type for
5309 case 2. To distinguish between the two cases, we note that
5310 CONTEXT of case 1 remains dependent type after tsubst while
5311 this isn't true for case 2. */
5312 ++processing_template_decl;
5313 dependent_p = dependent_type_p (context);
5314 --processing_template_decl;
5317 && !complete_type_or_else (context, NULL_TREE))
5318 return error_mark_node;
5320 if (COMPLETE_TYPE_P (context))
5322 /* Check to see that the declaration is really present, and,
5323 possibly obtain an improved declaration. */
5324 tree fn = check_classfn (context,
5325 new_friend, NULL_TREE);
5335 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5336 template arguments, as for tsubst.
5338 Returns an appropriate tsubst'd friend type or error_mark_node on
5342 tsubst_friend_class (tree friend_tmpl, tree args)
5348 context = DECL_CONTEXT (friend_tmpl);
5352 if (TREE_CODE (context) == NAMESPACE_DECL)
5353 push_nested_namespace (context);
5355 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5358 /* First, we look for a class template. */
5359 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5361 /* But, if we don't find one, it might be because we're in a
5362 situation like this:
5370 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5371 for `S<int>', not the TEMPLATE_DECL. */
5372 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5374 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5375 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5378 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5380 /* The friend template has already been declared. Just
5381 check to see that the declarations match, and install any new
5382 default parameters. We must tsubst the default parameters,
5383 of course. We only need the innermost template parameters
5384 because that is all that redeclare_class_template will look
5386 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5387 > TMPL_ARGS_DEPTH (args))
5390 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5391 args, tf_error | tf_warning);
5392 redeclare_class_template (TREE_TYPE (tmpl), parms);
5395 friend_type = TREE_TYPE (tmpl);
5399 /* The friend template has not already been declared. In this
5400 case, the instantiation of the template class will cause the
5401 injection of this template into the global scope. */
5402 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5404 /* The new TMPL is not an instantiation of anything, so we
5405 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5406 the new type because that is supposed to be the corresponding
5407 template decl, i.e., TMPL. */
5408 DECL_USE_TEMPLATE (tmpl) = 0;
5409 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5410 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5411 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5412 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5414 /* Inject this template into the global scope. */
5415 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5420 if (TREE_CODE (context) == NAMESPACE_DECL)
5421 pop_nested_namespace (context);
5423 pop_nested_class ();
5429 /* Returns zero if TYPE cannot be completed later due to circularity.
5430 Otherwise returns one. */
5433 can_complete_type_without_circularity (tree type)
5435 if (type == NULL_TREE || type == error_mark_node)
5437 else if (COMPLETE_TYPE_P (type))
5439 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5440 return can_complete_type_without_circularity (TREE_TYPE (type));
5441 else if (CLASS_TYPE_P (type)
5442 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5449 instantiate_class_template (tree type)
5451 tree template, args, pattern, t, member;
5456 if (type == error_mark_node)
5457 return error_mark_node;
5459 if (TYPE_BEING_DEFINED (type)
5460 || COMPLETE_TYPE_P (type)
5461 || dependent_type_p (type))
5464 /* Figure out which template is being instantiated. */
5465 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5466 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5468 /* Figure out which arguments are being used to do the
5470 args = CLASSTYPE_TI_ARGS (type);
5472 /* Determine what specialization of the original template to
5474 t = most_specialized_class (template, args);
5475 if (t == error_mark_node)
5477 const char *str = "candidates are:";
5478 error ("ambiguous class template instantiation for %q#T", type);
5479 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5482 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5484 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5488 TYPE_BEING_DEFINED (type) = 1;
5489 return error_mark_node;
5493 pattern = TREE_TYPE (t);
5495 pattern = TREE_TYPE (template);
5497 /* If the template we're instantiating is incomplete, then clearly
5498 there's nothing we can do. */
5499 if (!COMPLETE_TYPE_P (pattern))
5502 /* If we've recursively instantiated too many templates, stop. */
5503 if (! push_tinst_level (type))
5506 /* Now we're really doing the instantiation. Mark the type as in
5507 the process of being defined. */
5508 TYPE_BEING_DEFINED (type) = 1;
5510 /* We may be in the middle of deferred access check. Disable
5512 push_deferring_access_checks (dk_no_deferred);
5514 push_to_top_level ();
5518 /* This TYPE is actually an instantiation of a partial
5519 specialization. We replace the innermost set of ARGS with
5520 the arguments appropriate for substitution. For example,
5523 template <class T> struct S {};
5524 template <class T> struct S<T*> {};
5526 and supposing that we are instantiating S<int*>, ARGS will
5527 present be {int*} but we need {int}. */
5529 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5532 /* If there were multiple levels in ARGS, replacing the
5533 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5534 want, so we make a copy first. */
5535 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5537 args = copy_node (args);
5538 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5544 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5546 /* Set the input location to the template definition. This is needed
5547 if tsubsting causes an error. */
5548 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (pattern));
5550 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5551 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5552 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5553 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5554 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5555 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5556 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5557 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5558 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5559 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5560 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5561 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5562 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5563 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5564 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5565 if (ANON_AGGR_TYPE_P (pattern))
5566 SET_ANON_AGGR_TYPE_P (type);
5568 pbinfo = TYPE_BINFO (pattern);
5570 /* We should never instantiate a nested class before its enclosing
5571 class; we need to look up the nested class by name before we can
5572 instantiate it, and that lookup should instantiate the enclosing
5574 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5575 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5576 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5578 base_list = NULL_TREE;
5579 if (BINFO_N_BASE_BINFOS (pbinfo))
5582 tree context = TYPE_CONTEXT (type);
5586 /* We must enter the scope containing the type, as that is where
5587 the accessibility of types named in dependent bases are
5589 pop_p = push_scope (context ? context : global_namespace);
5591 /* Substitute into each of the bases to determine the actual
5593 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5596 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5598 /* Substitute to figure out the base class. */
5599 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5600 if (base == error_mark_node)
5603 base_list = tree_cons (access, base, base_list);
5604 if (BINFO_VIRTUAL_P (pbase_binfo))
5605 TREE_TYPE (base_list) = integer_type_node;
5608 /* The list is now in reverse order; correct that. */
5609 base_list = nreverse (base_list);
5612 pop_scope (context ? context : global_namespace);
5614 /* Now call xref_basetypes to set up all the base-class
5616 xref_basetypes (type, base_list);
5619 /* Now that our base classes are set up, enter the scope of the
5620 class, so that name lookups into base classes, etc. will work
5621 correctly. This is precisely analogous to what we do in
5622 begin_class_definition when defining an ordinary non-template
5626 /* Now members are processed in the order of declaration. */
5627 for (member = CLASSTYPE_DECL_LIST (pattern);
5628 member; member = TREE_CHAIN (member))
5630 tree t = TREE_VALUE (member);
5632 if (TREE_PURPOSE (member))
5636 /* Build new CLASSTYPE_NESTED_UTDS. */
5639 tree name = TYPE_IDENTIFIER (tag);
5641 bool class_template_p;
5643 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5644 && TYPE_LANG_SPECIFIC (tag)
5645 && CLASSTYPE_IS_TEMPLATE (tag));
5646 /* If the member is a class template, then -- even after
5647 substitution -- there may be dependent types in the
5648 template argument list for the class. We increment
5649 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5650 that function will assume that no types are dependent
5651 when outside of a template. */
5652 if (class_template_p)
5653 ++processing_template_decl;
5654 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5655 if (class_template_p)
5656 --processing_template_decl;
5657 if (newtag == error_mark_node)
5660 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5662 if (class_template_p)
5663 /* Unfortunately, lookup_template_class sets
5664 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5665 instantiation (i.e., for the type of a member
5666 template class nested within a template class.)
5667 This behavior is required for
5668 maybe_process_partial_specialization to work
5669 correctly, but is not accurate in this case;
5670 the TAG is not an instantiation of anything.
5671 (The corresponding TEMPLATE_DECL is an
5672 instantiation, but the TYPE is not.) */
5673 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5675 /* Now, we call pushtag to put this NEWTAG into the scope of
5676 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5677 pushtag calling push_template_decl. We don't have to do
5678 this for enums because it will already have been done in
5681 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5682 pushtag (name, newtag, /*globalize=*/0);
5685 else if (TREE_CODE (t) == FUNCTION_DECL
5686 || DECL_FUNCTION_TEMPLATE_P (t))
5688 /* Build new TYPE_METHODS. */
5691 if (TREE_CODE (t) == TEMPLATE_DECL)
5692 ++processing_template_decl;
5693 r = tsubst (t, args, tf_error, NULL_TREE);
5694 if (TREE_CODE (t) == TEMPLATE_DECL)
5695 --processing_template_decl;
5696 set_current_access_from_decl (r);
5697 grok_special_member_properties (r);
5698 finish_member_declaration (r);
5702 /* Build new TYPE_FIELDS. */
5704 if (TREE_CODE (t) != CONST_DECL)
5708 /* The the file and line for this declaration, to
5709 assist in error message reporting. Since we
5710 called push_tinst_level above, we don't need to
5712 input_location = DECL_SOURCE_LOCATION (t);
5714 if (TREE_CODE (t) == TEMPLATE_DECL)
5715 ++processing_template_decl;
5716 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5717 if (TREE_CODE (t) == TEMPLATE_DECL)
5718 --processing_template_decl;
5719 if (TREE_CODE (r) == VAR_DECL)
5723 if (DECL_INITIALIZED_IN_CLASS_P (r))
5724 init = tsubst_expr (DECL_INITIAL (t), args,
5725 tf_error | tf_warning, NULL_TREE);
5729 finish_static_data_member_decl
5730 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5732 if (DECL_INITIALIZED_IN_CLASS_P (r))
5733 check_static_variable_definition (r, TREE_TYPE (r));
5735 else if (TREE_CODE (r) == FIELD_DECL)
5737 /* Determine whether R has a valid type and can be
5738 completed later. If R is invalid, then it is
5739 replaced by error_mark_node so that it will not be
5740 added to TYPE_FIELDS. */
5741 tree rtype = TREE_TYPE (r);
5742 if (can_complete_type_without_circularity (rtype))
5743 complete_type (rtype);
5745 if (!COMPLETE_TYPE_P (rtype))
5747 cxx_incomplete_type_error (r, rtype);
5748 r = error_mark_node;
5752 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5753 such a thing will already have been added to the field
5754 list by tsubst_enum in finish_member_declaration in the
5755 CLASSTYPE_NESTED_UTDS case above. */
5756 if (!(TREE_CODE (r) == TYPE_DECL
5757 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5758 && DECL_ARTIFICIAL (r)))
5760 set_current_access_from_decl (r);
5761 finish_member_declaration (r);
5768 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5770 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5772 tree friend_type = t;
5773 bool adjust_processing_template_decl = false;
5775 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5777 friend_type = tsubst_friend_class (friend_type, args);
5778 adjust_processing_template_decl = true;
5780 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5782 friend_type = tsubst (friend_type, args,
5783 tf_error | tf_warning, NULL_TREE);
5784 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5785 friend_type = TREE_TYPE (friend_type);
5786 adjust_processing_template_decl = true;
5788 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5790 friend_type = tsubst (friend_type, args,
5791 tf_error | tf_warning, NULL_TREE);
5792 /* Bump processing_template_decl for correct
5793 dependent_type_p calculation. */
5794 ++processing_template_decl;
5795 if (dependent_type_p (friend_type))
5796 adjust_processing_template_decl = true;
5797 --processing_template_decl;
5799 else if (uses_template_parms (friend_type))
5800 friend_type = tsubst (friend_type, args,
5801 tf_error | tf_warning, NULL_TREE);
5802 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5803 friend_type = friend_type;
5806 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5808 /* The call to xref_tag_from_type does injection for friend
5810 push_nested_namespace (ns);
5812 xref_tag_from_type (friend_type, NULL_TREE,
5813 /*tag_scope=*/ts_global);
5814 pop_nested_namespace (ns);
5817 if (adjust_processing_template_decl)
5818 /* Trick make_friend_class into realizing that the friend
5819 we're adding is a template, not an ordinary class. It's
5820 important that we use make_friend_class since it will
5821 perform some error-checking and output cross-reference
5823 ++processing_template_decl;
5825 if (friend_type != error_mark_node)
5826 make_friend_class (type, friend_type, /*complain=*/false);
5828 if (adjust_processing_template_decl)
5829 --processing_template_decl;
5833 /* Build new DECL_FRIENDLIST. */
5836 /* The the file and line for this declaration, to
5837 assist in error message reporting. Since we
5838 called push_tinst_level above, we don't need to
5840 input_location = DECL_SOURCE_LOCATION (t);
5842 if (TREE_CODE (t) == TEMPLATE_DECL)
5844 ++processing_template_decl;
5845 push_deferring_access_checks (dk_no_check);
5848 r = tsubst_friend_function (t, args);
5849 add_friend (type, r, /*complain=*/false);
5850 if (TREE_CODE (t) == TEMPLATE_DECL)
5852 pop_deferring_access_checks ();
5853 --processing_template_decl;
5859 /* Set the file and line number information to whatever is given for
5860 the class itself. This puts error messages involving generated
5861 implicit functions at a predictable point, and the same point
5862 that would be used for non-template classes. */
5863 typedecl = TYPE_MAIN_DECL (type);
5864 input_location = DECL_SOURCE_LOCATION (typedecl);
5866 unreverse_member_declarations (type);
5867 finish_struct_1 (type);
5868 TYPE_BEING_DEFINED (type) = 0;
5870 /* Now that the class is complete, instantiate default arguments for
5871 any member functions. We don't do this earlier because the
5872 default arguments may reference members of the class. */
5873 if (!PRIMARY_TEMPLATE_P (template))
5874 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5875 if (TREE_CODE (t) == FUNCTION_DECL
5876 /* Implicitly generated member functions will not have template
5877 information; they are not instantiations, but instead are
5878 created "fresh" for each instantiation. */
5879 && DECL_TEMPLATE_INFO (t))
5880 tsubst_default_arguments (t);
5883 pop_from_top_level ();
5884 pop_deferring_access_checks ();
5887 /* The vtable for a template class can be emitted in any translation
5888 unit in which the class is instantiated. When there is no key
5889 method, however, finish_struct_1 will already have added TYPE to
5890 the keyed_classes list. */
5891 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5892 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5898 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5904 else if (TYPE_P (t))
5905 r = tsubst (t, args, complain, in_decl);
5908 r = tsubst_expr (t, args, complain, in_decl);
5910 if (!uses_template_parms (r))
5912 /* Sometimes, one of the args was an expression involving a
5913 template constant parameter, like N - 1. Now that we've
5914 tsubst'd, we might have something like 2 - 1. This will
5915 confuse lookup_template_class, so we do constant folding
5916 here. We have to unset processing_template_decl, to fool
5917 tsubst_copy_and_build() into building an actual tree. */
5919 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5920 as simple as it's going to get, and trying to reprocess
5921 the trees will break. Once tsubst_expr et al DTRT for
5922 non-dependent exprs, this code can go away, as the type
5923 will always be set. */
5926 int saved_processing_template_decl = processing_template_decl;
5927 processing_template_decl = 0;
5928 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5929 tf_error, /*in_decl=*/NULL_TREE,
5930 /*function_p=*/false);
5931 processing_template_decl = saved_processing_template_decl;
5939 /* Substitute ARGS into the vector or list of template arguments T. */
5942 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5944 int len = TREE_VEC_LENGTH (t);
5945 int need_new = 0, i;
5946 tree *elts = alloca (len * sizeof (tree));
5948 for (i = 0; i < len; i++)
5950 tree orig_arg = TREE_VEC_ELT (t, i);
5953 if (TREE_CODE (orig_arg) == TREE_VEC)
5954 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5956 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5958 if (new_arg == error_mark_node)
5959 return error_mark_node;
5962 if (new_arg != orig_arg)
5969 t = make_tree_vec (len);
5970 for (i = 0; i < len; i++)
5971 TREE_VEC_ELT (t, i) = elts[i];
5976 /* Return the result of substituting ARGS into the template parameters
5977 given by PARMS. If there are m levels of ARGS and m + n levels of
5978 PARMS, then the result will contain n levels of PARMS. For
5979 example, if PARMS is `template <class T> template <class U>
5980 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5981 result will be `template <int*, double, class V>'. */
5984 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5989 for (new_parms = &r;
5990 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5991 new_parms = &(TREE_CHAIN (*new_parms)),
5992 parms = TREE_CHAIN (parms))
5995 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5998 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
6000 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
6001 tree default_value = TREE_PURPOSE (tuple);
6002 tree parm_decl = TREE_VALUE (tuple);
6004 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
6005 default_value = tsubst_template_arg (default_value, args,
6006 complain, NULL_TREE);
6008 tuple = build_tree_list (default_value, parm_decl);
6009 TREE_VEC_ELT (new_vec, i) = tuple;
6013 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6014 - TMPL_ARGS_DEPTH (args)),
6015 new_vec, NULL_TREE);
6021 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6022 type T. If T is not an aggregate or enumeration type, it is
6023 handled as if by tsubst. IN_DECL is as for tsubst. If
6024 ENTERING_SCOPE is nonzero, T is the context for a template which
6025 we are presently tsubst'ing. Return the substituted value. */
6028 tsubst_aggr_type (tree t,
6030 tsubst_flags_t complain,
6037 switch (TREE_CODE (t))
6040 if (TYPE_PTRMEMFUNC_P (t))
6041 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6043 /* Else fall through. */
6046 if (TYPE_TEMPLATE_INFO (t))
6052 /* First, determine the context for the type we are looking
6054 context = TYPE_CONTEXT (t);
6056 context = tsubst_aggr_type (context, args, complain,
6057 in_decl, /*entering_scope=*/1);
6059 /* Then, figure out what arguments are appropriate for the
6060 type we are trying to find. For example, given:
6062 template <class T> struct S;
6063 template <class T, class U> void f(T, U) { S<U> su; }
6065 and supposing that we are instantiating f<int, double>,
6066 then our ARGS will be {int, double}, but, when looking up
6067 S we only want {double}. */
6068 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6070 if (argvec == error_mark_node)
6071 return error_mark_node;
6073 r = lookup_template_class (t, argvec, in_decl, context,
6074 entering_scope, complain);
6076 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6079 /* This is not a template type, so there's nothing to do. */
6083 return tsubst (t, args, complain, in_decl);
6087 /* Substitute into the default argument ARG (a default argument for
6088 FN), which has the indicated TYPE. */
6091 tsubst_default_argument (tree fn, tree type, tree arg)
6093 tree saved_class_ptr = NULL_TREE;
6094 tree saved_class_ref = NULL_TREE;
6096 /* This default argument came from a template. Instantiate the
6097 default argument here, not in tsubst. In the case of
6106 we must be careful to do name lookup in the scope of S<T>,
6107 rather than in the current class. */
6108 push_access_scope (fn);
6109 /* The default argument expression should not be considered to be
6110 within the scope of FN. Since push_access_scope sets
6111 current_function_decl, we must explicitly clear it here. */
6112 current_function_decl = NULL_TREE;
6113 /* The "this" pointer is not valid in a default argument. */
6116 saved_class_ptr = current_class_ptr;
6117 cp_function_chain->x_current_class_ptr = NULL_TREE;
6118 saved_class_ref = current_class_ref;
6119 cp_function_chain->x_current_class_ref = NULL_TREE;
6122 push_deferring_access_checks(dk_no_deferred);
6123 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6124 tf_error | tf_warning, NULL_TREE);
6125 pop_deferring_access_checks();
6127 /* Restore the "this" pointer. */
6130 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6131 cp_function_chain->x_current_class_ref = saved_class_ref;
6134 pop_access_scope (fn);
6136 /* Make sure the default argument is reasonable. */
6137 arg = check_default_argument (type, arg);
6142 /* Substitute into all the default arguments for FN. */
6145 tsubst_default_arguments (tree fn)
6150 tmpl_args = DECL_TI_ARGS (fn);
6152 /* If this function is not yet instantiated, we certainly don't need
6153 its default arguments. */
6154 if (uses_template_parms (tmpl_args))
6157 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6159 arg = TREE_CHAIN (arg))
6160 if (TREE_PURPOSE (arg))
6161 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6163 TREE_PURPOSE (arg));
6166 /* Substitute the ARGS into the T, which is a _DECL. Return the
6167 result of the substitution. Issue error and warning messages under
6168 control of COMPLAIN. */
6171 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6173 location_t saved_loc;
6177 /* Set the filename and linenumber to improve error-reporting. */
6178 saved_loc = input_location;
6179 input_location = DECL_SOURCE_LOCATION (t);
6181 switch (TREE_CODE (t))
6185 /* We can get here when processing a member function template,
6186 member class template, and template template parameter of
6187 a template class. */
6188 tree decl = DECL_TEMPLATE_RESULT (t);
6193 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6195 /* Template template parameter is treated here. */
6196 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6197 if (new_type == error_mark_node)
6198 return error_mark_node;
6201 TREE_CHAIN (r) = NULL_TREE;
6202 TREE_TYPE (r) = new_type;
6203 DECL_TEMPLATE_RESULT (r)
6204 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6205 DECL_TEMPLATE_PARMS (r)
6206 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6208 TYPE_NAME (new_type) = r;
6212 /* We might already have an instance of this template.
6213 The ARGS are for the surrounding class type, so the
6214 full args contain the tsubst'd args for the context,
6215 plus the innermost args from the template decl. */
6216 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6217 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6218 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6219 full_args = tsubst_template_args (tmpl_args, args,
6222 /* tsubst_template_args doesn't copy the vector if
6223 nothing changed. But, *something* should have
6225 gcc_assert (full_args != tmpl_args);
6227 spec = retrieve_specialization (t, full_args,
6228 /*class_specializations_p=*/true);
6229 if (spec != NULL_TREE)
6235 /* Make a new template decl. It will be similar to the
6236 original, but will record the current template arguments.
6237 We also create a new function declaration, which is just
6238 like the old one, but points to this new template, rather
6239 than the old one. */
6241 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6242 TREE_CHAIN (r) = NULL_TREE;
6245 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6247 /*entering_scope=*/1);
6248 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6250 if (TREE_CODE (decl) == TYPE_DECL)
6252 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6253 if (new_type == error_mark_node)
6254 return error_mark_node;
6256 TREE_TYPE (r) = new_type;
6257 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6258 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6259 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6263 tree new_decl = tsubst (decl, args, complain, in_decl);
6264 if (new_decl == error_mark_node)
6265 return error_mark_node;
6267 DECL_TEMPLATE_RESULT (r) = new_decl;
6268 DECL_TI_TEMPLATE (new_decl) = r;
6269 TREE_TYPE (r) = TREE_TYPE (new_decl);
6270 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6273 SET_DECL_IMPLICIT_INSTANTIATION (r);
6274 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6275 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6277 /* The template parameters for this new template are all the
6278 template parameters for the old template, except the
6279 outermost level of parameters. */
6280 DECL_TEMPLATE_PARMS (r)
6281 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6284 if (PRIMARY_TEMPLATE_P (t))
6285 DECL_PRIMARY_TEMPLATE (r) = r;
6287 if (TREE_CODE (decl) != TYPE_DECL)
6288 /* Record this non-type partial instantiation. */
6289 register_specialization (r, t,
6290 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6297 tree argvec = NULL_TREE;
6305 /* Nobody should be tsubst'ing into non-template functions. */
6306 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6308 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6313 /* If T is not dependent, just return it. We have to
6314 increment PROCESSING_TEMPLATE_DECL because
6315 value_dependent_expression_p assumes that nothing is
6316 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6317 ++processing_template_decl;
6318 dependent_p = value_dependent_expression_p (t);
6319 --processing_template_decl;
6323 /* Calculate the most general template of which R is a
6324 specialization, and the complete set of arguments used to
6326 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6327 argvec = tsubst_template_args (DECL_TI_ARGS
6328 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6329 args, complain, in_decl);
6331 /* Check to see if we already have this specialization. */
6332 spec = retrieve_specialization (gen_tmpl, argvec,
6333 /*class_specializations_p=*/false);
6341 /* We can see more levels of arguments than parameters if
6342 there was a specialization of a member template, like
6345 template <class T> struct S { template <class U> void f(); }
6346 template <> template <class U> void S<int>::f(U);
6348 Here, we'll be substituting into the specialization,
6349 because that's where we can find the code we actually
6350 want to generate, but we'll have enough arguments for
6351 the most general template.
6353 We also deal with the peculiar case:
6355 template <class T> struct S {
6356 template <class U> friend void f();
6358 template <class U> void f() {}
6360 template void f<double>();
6362 Here, the ARGS for the instantiation of will be {int,
6363 double}. But, we only need as many ARGS as there are
6364 levels of template parameters in CODE_PATTERN. We are
6365 careful not to get fooled into reducing the ARGS in
6368 template <class T> struct S { template <class U> void f(U); }
6369 template <class T> template <> void S<T>::f(int) {}
6371 which we can spot because the pattern will be a
6372 specialization in this case. */
6373 args_depth = TMPL_ARGS_DEPTH (args);
6375 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6376 if (args_depth > parms_depth
6377 && !DECL_TEMPLATE_SPECIALIZATION (t))
6378 args = get_innermost_template_args (args, parms_depth);
6382 /* This special case arises when we have something like this:
6384 template <class T> struct S {
6385 friend void f<int>(int, double);
6388 Here, the DECL_TI_TEMPLATE for the friend declaration
6389 will be an IDENTIFIER_NODE. We are being called from
6390 tsubst_friend_function, and we want only to create a
6391 new decl (R) with appropriate types so that we can call
6392 determine_specialization. */
6393 gen_tmpl = NULL_TREE;
6396 if (DECL_CLASS_SCOPE_P (t))
6398 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6402 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6403 complain, t, /*entering_scope=*/1);
6408 ctx = DECL_CONTEXT (t);
6410 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6411 if (type == error_mark_node)
6412 return error_mark_node;
6414 /* We do NOT check for matching decls pushed separately at this
6415 point, as they may not represent instantiations of this
6416 template, and in any case are considered separate under the
6419 DECL_USE_TEMPLATE (r) = 0;
6420 TREE_TYPE (r) = type;
6421 /* Clear out the mangled name and RTL for the instantiation. */
6422 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6423 SET_DECL_RTL (r, NULL_RTX);
6424 DECL_INITIAL (r) = NULL_TREE;
6425 DECL_CONTEXT (r) = ctx;
6427 if (member && DECL_CONV_FN_P (r))
6428 /* Type-conversion operator. Reconstruct the name, in
6429 case it's the name of one of the template's parameters. */
6430 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6432 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6434 DECL_RESULT (r) = NULL_TREE;
6436 TREE_STATIC (r) = 0;
6437 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6438 DECL_EXTERNAL (r) = 1;
6439 /* If this is an instantiation of a function with internal
6440 linkage, we already know what object file linkage will be
6441 assigned to the instantiation. */
6442 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6443 DECL_DEFER_OUTPUT (r) = 0;
6444 TREE_CHAIN (r) = NULL_TREE;
6445 DECL_PENDING_INLINE_INFO (r) = 0;
6446 DECL_PENDING_INLINE_P (r) = 0;
6447 DECL_SAVED_TREE (r) = NULL_TREE;
6449 if (DECL_CLONED_FUNCTION (r))
6451 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6453 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6454 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6457 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6458 this in the special friend case mentioned above where
6459 GEN_TMPL is NULL. */
6462 DECL_TEMPLATE_INFO (r)
6463 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6464 SET_DECL_IMPLICIT_INSTANTIATION (r);
6465 register_specialization (r, gen_tmpl, argvec);
6467 /* We're not supposed to instantiate default arguments
6468 until they are called, for a template. But, for a
6471 template <class T> void f ()
6472 { extern void g(int i = T()); }
6474 we should do the substitution when the template is
6475 instantiated. We handle the member function case in
6476 instantiate_class_template since the default arguments
6477 might refer to other members of the class. */
6479 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6480 && !uses_template_parms (argvec))
6481 tsubst_default_arguments (r);
6484 /* Copy the list of befriending classes. */
6485 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6487 friends = &TREE_CHAIN (*friends))
6489 *friends = copy_node (*friends);
6490 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6495 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6497 maybe_retrofit_in_chrg (r);
6498 if (DECL_CONSTRUCTOR_P (r))
6499 grok_ctor_properties (ctx, r);
6500 /* If this is an instantiation of a member template, clone it.
6501 If it isn't, that'll be handled by
6502 clone_constructors_and_destructors. */
6503 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6504 clone_function_decl (r, /*update_method_vec_p=*/0);
6506 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6507 grok_op_properties (r, DECL_FRIEND_P (r),
6508 (complain & tf_error) != 0);
6510 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6511 SET_DECL_FRIEND_CONTEXT (r,
6512 tsubst (DECL_FRIEND_CONTEXT (t),
6513 args, complain, in_decl));
6522 if (DECL_TEMPLATE_PARM_P (t))
6523 SET_DECL_TEMPLATE_PARM_P (r);
6525 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6526 TREE_TYPE (r) = type;
6527 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6529 if (DECL_INITIAL (r))
6531 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6532 DECL_INITIAL (r) = TREE_TYPE (r);
6534 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6538 DECL_CONTEXT (r) = NULL_TREE;
6540 if (!DECL_TEMPLATE_PARM_P (r))
6541 DECL_ARG_TYPE (r) = type_passed_as (type);
6543 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6544 complain, TREE_CHAIN (t));
6553 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6554 if (type == error_mark_node)
6555 return error_mark_node;
6556 TREE_TYPE (r) = type;
6557 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6559 /* We don't have to set DECL_CONTEXT here; it is set by
6560 finish_member_declaration. */
6561 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6563 TREE_CHAIN (r) = NULL_TREE;
6564 if (VOID_TYPE_P (type))
6565 cp_error_at ("instantiation of %qD as type %qT", r, type);
6572 /* It is not a dependent using decl any more. */
6573 TREE_TYPE (r) = void_type_node;
6575 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6577 = tsubst_copy (DECL_NAME (t), args, complain, in_decl);
6578 TREE_CHAIN (r) = NULL_TREE;
6585 tree argvec = NULL_TREE;
6586 tree gen_tmpl = NULL_TREE;
6588 tree tmpl = NULL_TREE;
6590 tree type = NULL_TREE;
6593 if (TREE_CODE (t) == TYPE_DECL)
6595 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6596 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6597 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6599 /* If this is the canonical decl, we don't have to
6600 mess with instantiations, and often we can't (for
6601 typename, template type parms and such). Note that
6602 TYPE_NAME is not correct for the above test if
6603 we've copied the type for a typedef. */
6604 r = TYPE_NAME (type);
6609 /* Assume this is a non-local variable. */
6612 if (TYPE_P (CP_DECL_CONTEXT (t)))
6613 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6615 in_decl, /*entering_scope=*/1);
6616 else if (DECL_NAMESPACE_SCOPE_P (t))
6617 ctx = DECL_CONTEXT (t);
6620 /* Subsequent calls to pushdecl will fill this in. */
6625 /* Check to see if we already have this specialization. */
6628 tmpl = DECL_TI_TEMPLATE (t);
6629 gen_tmpl = most_general_template (tmpl);
6630 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6631 spec = retrieve_specialization (gen_tmpl, argvec,
6632 /*class_specializations_p=*/false);
6635 spec = retrieve_local_specialization (t);
6644 if (TREE_CODE (r) == VAR_DECL)
6646 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6647 if (type == error_mark_node)
6648 return error_mark_node;
6649 type = complete_type (type);
6650 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6651 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6652 type = check_var_type (DECL_NAME (r), type);
6654 else if (DECL_SELF_REFERENCE_P (t))
6655 SET_DECL_SELF_REFERENCE_P (r);
6656 TREE_TYPE (r) = type;
6657 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6658 DECL_CONTEXT (r) = ctx;
6659 /* Clear out the mangled name and RTL for the instantiation. */
6660 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6661 SET_DECL_RTL (r, NULL_RTX);
6663 /* Don't try to expand the initializer until someone tries to use
6664 this variable; otherwise we run into circular dependencies. */
6665 DECL_INITIAL (r) = NULL_TREE;
6666 SET_DECL_RTL (r, NULL_RTX);
6667 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6669 /* Even if the original location is out of scope, the newly
6670 substituted one is not. */
6671 if (TREE_CODE (r) == VAR_DECL)
6673 DECL_DEAD_FOR_LOCAL (r) = 0;
6674 DECL_INITIALIZED_P (r) = 0;
6679 /* A static data member declaration is always marked
6680 external when it is declared in-class, even if an
6681 initializer is present. We mimic the non-template
6683 DECL_EXTERNAL (r) = 1;
6685 register_specialization (r, gen_tmpl, argvec);
6686 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6687 SET_DECL_IMPLICIT_INSTANTIATION (r);
6690 register_local_specialization (r, t);
6692 TREE_CHAIN (r) = NULL_TREE;
6701 /* Restore the file and line information. */
6702 input_location = saved_loc;
6707 /* Substitute into the ARG_TYPES of a function type. */
6710 tsubst_arg_types (tree arg_types,
6712 tsubst_flags_t complain,
6715 tree remaining_arg_types;
6718 if (!arg_types || arg_types == void_list_node)
6721 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6722 args, complain, in_decl);
6723 if (remaining_arg_types == error_mark_node)
6724 return error_mark_node;
6726 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6727 if (type == error_mark_node)
6728 return error_mark_node;
6729 if (VOID_TYPE_P (type))
6731 if (complain & tf_error)
6733 error ("invalid parameter type %qT", type);
6735 cp_error_at ("in declaration %qD", in_decl);
6737 return error_mark_node;
6740 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6741 top-level qualifiers as required. */
6742 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6744 /* Note that we do not substitute into default arguments here. The
6745 standard mandates that they be instantiated only when needed,
6746 which is done in build_over_call. */
6747 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6748 remaining_arg_types);
6752 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6753 *not* handle the exception-specification for FNTYPE, because the
6754 initial substitution of explicitly provided template parameters
6755 during argument deduction forbids substitution into the
6756 exception-specification:
6760 All references in the function type of the function template to the
6761 corresponding template parameters are replaced by the specified tem-
6762 plate argument values. If a substitution in a template parameter or
6763 in the function type of the function template results in an invalid
6764 type, type deduction fails. [Note: The equivalent substitution in
6765 exception specifications is done only when the function is instanti-
6766 ated, at which point a program is ill-formed if the substitution
6767 results in an invalid type.] */
6770 tsubst_function_type (tree t,
6772 tsubst_flags_t complain,
6779 /* The TYPE_CONTEXT is not used for function/method types. */
6780 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6782 /* Substitute the return type. */
6783 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6784 if (return_type == error_mark_node)
6785 return error_mark_node;
6786 /* The standard does not presently indicate that creation of a
6787 function type with an invalid return type is a deduction failure.
6788 However, that is clearly analogous to creating an array of "void"
6789 or a reference to a reference. This is core issue #486. */
6790 if (TREE_CODE (return_type) == ARRAY_TYPE
6791 || TREE_CODE (return_type) == FUNCTION_TYPE)
6793 if (complain & tf_error)
6795 if (TREE_CODE (return_type) == ARRAY_TYPE)
6796 error ("function returning an array");
6798 error ("function returning a function");
6800 return error_mark_node;
6803 /* Substitute the argument types. */
6804 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6806 if (arg_types == error_mark_node)
6807 return error_mark_node;
6809 /* Construct a new type node and return it. */
6810 if (TREE_CODE (t) == FUNCTION_TYPE)
6811 fntype = build_function_type (return_type, arg_types);
6814 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6815 if (! IS_AGGR_TYPE (r))
6819 Type deduction may fail for any of the following
6822 -- Attempting to create "pointer to member of T" when T
6823 is not a class type. */
6824 if (complain & tf_error)
6825 error ("creating pointer to member function of non-class type %qT",
6827 return error_mark_node;
6830 fntype = build_method_type_directly (r, return_type,
6831 TREE_CHAIN (arg_types));
6833 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6834 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6839 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6840 ARGS into that specification, and return the substituted
6841 specification. If there is no specification, return NULL_TREE. */
6844 tsubst_exception_specification (tree fntype,
6846 tsubst_flags_t complain,
6852 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6853 new_specs = NULL_TREE;
6856 if (! TREE_VALUE (specs))
6862 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6863 if (spec == error_mark_node)
6865 new_specs = add_exception_specifier (new_specs, spec, complain);
6866 specs = TREE_CHAIN (specs);
6872 /* Substitute into the PARMS of a call-declarator. */
6875 tsubst_call_declarator_parms (tree parms,
6877 tsubst_flags_t complain,
6884 if (!parms || parms == void_list_node)
6887 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6888 args, complain, in_decl);
6890 /* Figure out the type of this parameter. */
6891 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6893 /* Figure out the default argument as well. Note that we use
6894 tsubst_expr since the default argument is really an expression. */
6895 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6897 /* Chain this parameter on to the front of those we have already
6898 processed. We don't use hash_tree_cons because that function
6899 doesn't check TREE_PARMLIST. */
6900 new_parms = tree_cons (defarg, type, new_parms);
6905 /* Take the tree structure T and replace template parameters used
6906 therein with the argument vector ARGS. IN_DECL is an associated
6907 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6908 Issue error and warning messages under control of COMPLAIN. Note
6909 that we must be relatively non-tolerant of extensions here, in
6910 order to preserve conformance; if we allow substitutions that
6911 should not be allowed, we may allow argument deductions that should
6912 not succeed, and therefore report ambiguous overload situations
6913 where there are none. In theory, we could allow the substitution,
6914 but indicate that it should have failed, and allow our caller to
6915 make sure that the right thing happens, but we don't try to do this
6918 This function is used for dealing with types, decls and the like;
6919 for expressions, use tsubst_expr or tsubst_copy. */
6922 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6926 if (t == NULL_TREE || t == error_mark_node
6927 || t == integer_type_node
6928 || t == void_type_node
6929 || t == char_type_node
6930 || t == unknown_type_node
6931 || TREE_CODE (t) == NAMESPACE_DECL)
6935 return tsubst_decl (t, args, complain);
6937 if (TREE_CODE (t) == IDENTIFIER_NODE)
6938 type = IDENTIFIER_TYPE_VALUE (t);
6940 type = TREE_TYPE (t);
6942 gcc_assert (type != unknown_type_node);
6945 && TREE_CODE (t) != TYPENAME_TYPE
6946 && TREE_CODE (t) != IDENTIFIER_NODE
6947 && TREE_CODE (t) != FUNCTION_TYPE
6948 && TREE_CODE (t) != METHOD_TYPE)
6949 type = tsubst (type, args, complain, in_decl);
6950 if (type == error_mark_node)
6951 return error_mark_node;
6953 switch (TREE_CODE (t))
6958 return tsubst_aggr_type (t, args, complain, in_decl,
6959 /*entering_scope=*/0);
6962 case IDENTIFIER_NODE:
6974 if (t == integer_type_node)
6977 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6978 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6982 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6984 /* The array dimension behaves like a non-type template arg,
6985 in that we want to fold it as much as possible. */
6986 max = tsubst_template_arg (omax, args, complain, in_decl);
6987 if (!processing_template_decl)
6988 max = decl_constant_value (max);
6990 if (integer_zerop (omax))
6992 /* Still allow an explicit array of size zero. */
6994 pedwarn ("creating array with size zero");
6996 else if (integer_zerop (max)
6997 || (TREE_CODE (max) == INTEGER_CST
6998 && INT_CST_LT (max, integer_zero_node)))
7002 Type deduction may fail for any of the following
7005 Attempting to create an array with a size that is
7006 zero or negative. */
7007 if (complain & tf_error)
7008 error ("creating array with size zero (%qE)", max);
7010 return error_mark_node;
7013 return compute_array_index_type (NULL_TREE, max);
7016 case TEMPLATE_TYPE_PARM:
7017 case TEMPLATE_TEMPLATE_PARM:
7018 case BOUND_TEMPLATE_TEMPLATE_PARM:
7019 case TEMPLATE_PARM_INDEX:
7024 tree arg = NULL_TREE;
7028 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7029 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7030 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7031 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7033 idx = TEMPLATE_TYPE_IDX (t);
7034 level = TEMPLATE_TYPE_LEVEL (t);
7038 idx = TEMPLATE_PARM_IDX (t);
7039 level = TEMPLATE_PARM_LEVEL (t);
7042 levels = TMPL_ARGS_DEPTH (args);
7043 if (level <= levels)
7044 arg = TMPL_ARG (args, level, idx);
7046 if (arg == error_mark_node)
7047 return error_mark_node;
7048 else if (arg != NULL_TREE)
7050 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7052 gcc_assert (TYPE_P (arg));
7053 return cp_build_qualified_type_real
7054 (arg, cp_type_quals (arg) | cp_type_quals (t),
7055 complain | tf_ignore_bad_quals);
7057 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7059 /* We are processing a type constructed from a
7060 template template parameter. */
7061 tree argvec = tsubst (TYPE_TI_ARGS (t),
7062 args, complain, in_decl);
7063 if (argvec == error_mark_node)
7064 return error_mark_node;
7066 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7067 are resolving nested-types in the signature of a
7068 member function templates. Otherwise ARG is a
7069 TEMPLATE_DECL and is the real template to be
7071 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7072 arg = TYPE_NAME (arg);
7074 r = lookup_template_class (arg,
7077 /*entering_scope=*/0,
7079 return cp_build_qualified_type_real
7080 (r, TYPE_QUALS (t), complain);
7083 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7088 /* This can happen during the attempted tsubst'ing in
7089 unify. This means that we don't yet have any information
7090 about the template parameter in question. */
7093 /* If we get here, we must have been looking at a parm for a
7094 more deeply nested template. Make a new version of this
7095 template parameter, but with a lower level. */
7096 switch (TREE_CODE (t))
7098 case TEMPLATE_TYPE_PARM:
7099 case TEMPLATE_TEMPLATE_PARM:
7100 case BOUND_TEMPLATE_TEMPLATE_PARM:
7101 if (cp_type_quals (t))
7103 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7104 r = cp_build_qualified_type_real
7105 (r, cp_type_quals (t),
7106 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7107 ? tf_ignore_bad_quals : 0));
7112 TEMPLATE_TYPE_PARM_INDEX (r)
7113 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7115 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7116 TYPE_MAIN_VARIANT (r) = r;
7117 TYPE_POINTER_TO (r) = NULL_TREE;
7118 TYPE_REFERENCE_TO (r) = NULL_TREE;
7120 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7122 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7124 if (argvec == error_mark_node)
7125 return error_mark_node;
7127 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7128 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7133 case TEMPLATE_PARM_INDEX:
7134 r = reduce_template_parm_level (t, type, levels);
7146 tree purpose, value, chain;
7148 if (t == void_list_node)
7151 purpose = TREE_PURPOSE (t);
7154 purpose = tsubst (purpose, args, complain, in_decl);
7155 if (purpose == error_mark_node)
7156 return error_mark_node;
7158 value = TREE_VALUE (t);
7161 value = tsubst (value, args, complain, in_decl);
7162 if (value == error_mark_node)
7163 return error_mark_node;
7165 chain = TREE_CHAIN (t);
7166 if (chain && chain != void_type_node)
7168 chain = tsubst (chain, args, complain, in_decl);
7169 if (chain == error_mark_node)
7170 return error_mark_node;
7172 if (purpose == TREE_PURPOSE (t)
7173 && value == TREE_VALUE (t)
7174 && chain == TREE_CHAIN (t))
7176 return hash_tree_cons (purpose, value, chain);
7180 /* We should never be tsubsting a binfo. */
7184 /* A vector of template arguments. */
7186 return tsubst_template_args (t, args, complain, in_decl);
7189 case REFERENCE_TYPE:
7191 enum tree_code code;
7193 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7196 code = TREE_CODE (t);
7201 Type deduction may fail for any of the following
7204 -- Attempting to create a pointer to reference type.
7205 -- Attempting to create a reference to a reference type or
7206 a reference to void. */
7207 if (TREE_CODE (type) == REFERENCE_TYPE
7208 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7210 static location_t last_loc;
7212 /* We keep track of the last time we issued this error
7213 message to avoid spewing a ton of messages during a
7214 single bad template instantiation. */
7215 if (complain & tf_error
7216 #ifdef USE_MAPPED_LOCATION
7217 && last_loc != input_location
7219 && (last_loc.line != input_line
7220 || last_loc.file != input_filename)
7224 if (TREE_CODE (type) == VOID_TYPE)
7225 error ("forming reference to void");
7227 error ("forming %s to reference type %qT",
7228 (code == POINTER_TYPE) ? "pointer" : "reference",
7230 last_loc = input_location;
7233 return error_mark_node;
7235 else if (code == POINTER_TYPE)
7237 r = build_pointer_type (type);
7238 if (TREE_CODE (type) == METHOD_TYPE)
7239 r = build_ptrmemfunc_type (r);
7242 r = build_reference_type (type);
7243 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7245 if (r != error_mark_node)
7246 /* Will this ever be needed for TYPE_..._TO values? */
7253 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7254 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7258 Type deduction may fail for any of the following
7261 -- Attempting to create "pointer to member of T" when T
7262 is not a class type. */
7263 if (complain & tf_error)
7264 error ("creating pointer to member of non-class type %qT", r);
7265 return error_mark_node;
7267 if (TREE_CODE (type) == REFERENCE_TYPE)
7269 if (complain & tf_error)
7270 error ("creating pointer to member reference type %qT", type);
7272 return error_mark_node;
7274 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7275 if (TREE_CODE (type) == FUNCTION_TYPE)
7277 /* This is really a method type. The cv qualifiers of the
7278 this pointer should _not_ be determined by the cv
7279 qualifiers of the class type. They should be held
7280 somewhere in the FUNCTION_TYPE, but we don't do that at
7281 the moment. Consider
7282 typedef void (Func) () const;
7284 template <typename T1> void Foo (Func T1::*);
7289 method_type = build_method_type_directly (TYPE_MAIN_VARIANT (r),
7291 TYPE_ARG_TYPES (type));
7292 return build_ptrmemfunc_type (build_pointer_type (method_type));
7295 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7304 fntype = tsubst_function_type (t, args, complain, in_decl);
7305 if (fntype == error_mark_node)
7306 return error_mark_node;
7308 /* Substitute the exception specification. */
7309 specs = tsubst_exception_specification (t, args, complain,
7312 fntype = build_exception_variant (fntype, specs);
7317 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7318 if (domain == error_mark_node)
7319 return error_mark_node;
7321 /* As an optimization, we avoid regenerating the array type if
7322 it will obviously be the same as T. */
7323 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7326 /* These checks should match the ones in grokdeclarator.
7330 The deduction may fail for any of the following reasons:
7332 -- Attempting to create an array with an element type that
7333 is void, a function type, or a reference type, or [DR337]
7334 an abstract class type. */
7335 if (TREE_CODE (type) == VOID_TYPE
7336 || TREE_CODE (type) == FUNCTION_TYPE
7337 || TREE_CODE (type) == REFERENCE_TYPE)
7339 if (complain & tf_error)
7340 error ("creating array of %qT", type);
7341 return error_mark_node;
7343 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7345 if (complain & tf_error)
7346 error ("creating array of %qT, which is an abstract class type",
7348 return error_mark_node;
7351 r = build_cplus_array_type (type, domain);
7358 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7359 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7361 if (e1 == error_mark_node || e2 == error_mark_node)
7362 return error_mark_node;
7364 return fold (build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2));
7370 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7371 if (e == error_mark_node)
7372 return error_mark_node;
7374 return fold (build1 (TREE_CODE (t), TREE_TYPE (t), e));
7379 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7380 in_decl, /*entering_scope=*/1);
7381 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7384 if (ctx == error_mark_node || f == error_mark_node)
7385 return error_mark_node;
7387 if (!IS_AGGR_TYPE (ctx))
7389 if (complain & tf_error)
7390 error ("%qT is not a class, struct, or union type", ctx);
7391 return error_mark_node;
7393 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7395 /* Normally, make_typename_type does not require that the CTX
7396 have complete type in order to allow things like:
7398 template <class T> struct S { typename S<T>::X Y; };
7400 But, such constructs have already been resolved by this
7401 point, so here CTX really should have complete type, unless
7402 it's a partial instantiation. */
7403 ctx = complete_type (ctx);
7404 if (!COMPLETE_TYPE_P (ctx))
7406 if (complain & tf_error)
7407 cxx_incomplete_type_error (NULL_TREE, ctx);
7408 return error_mark_node;
7412 f = make_typename_type (ctx, f, typename_type,
7413 (complain & tf_error) | tf_keep_type_decl);
7414 if (f == error_mark_node)
7416 if (TREE_CODE (f) == TYPE_DECL)
7418 complain |= tf_ignore_bad_quals;
7422 if (TREE_CODE (f) != TYPENAME_TYPE)
7424 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7425 error ("%qT resolves to %qT, which is not an enumeration type",
7427 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7428 error ("%qT resolves to %qT, which is is not a class type",
7432 return cp_build_qualified_type_real
7433 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7436 case UNBOUND_CLASS_TEMPLATE:
7438 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7439 in_decl, /*entering_scope=*/1);
7440 tree name = TYPE_IDENTIFIER (t);
7441 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7443 if (ctx == error_mark_node || name == error_mark_node)
7444 return error_mark_node;
7447 parm_list = tsubst_template_parms (parm_list, args, complain);
7448 return make_unbound_class_template (ctx, name, parm_list, complain);
7458 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7459 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7460 if (e1 == error_mark_node || e2 == error_mark_node)
7461 return error_mark_node;
7463 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7468 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7469 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7470 if (e1 == error_mark_node || e2 == error_mark_node)
7471 return error_mark_node;
7473 return build_nt (TREE_CODE (t), e1, e2);
7480 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7481 complain, in_decl));
7482 return cp_build_qualified_type_real (type,
7484 | cp_type_quals (type),
7489 sorry ("use of %qs in template",
7490 tree_code_name [(int) TREE_CODE (t)]);
7491 return error_mark_node;
7495 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7496 type of the expression on the left-hand side of the "." or "->"
7500 tsubst_baselink (tree baselink, tree object_type,
7501 tree args, tsubst_flags_t complain, tree in_decl)
7504 tree qualifying_scope;
7506 tree template_args = 0;
7507 bool template_id_p = false;
7509 /* A baselink indicates a function from a base class. The
7510 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7511 non-dependent types; otherwise, the lookup could not have
7512 succeeded. However, they may indicate bases of the template
7513 class, rather than the instantiated class.
7515 In addition, lookups that were not ambiguous before may be
7516 ambiguous now. Therefore, we perform the lookup again. */
7517 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7518 fns = BASELINK_FUNCTIONS (baselink);
7519 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7521 template_id_p = true;
7522 template_args = TREE_OPERAND (fns, 1);
7523 fns = TREE_OPERAND (fns, 0);
7525 template_args = tsubst_template_args (template_args, args,
7528 name = DECL_NAME (get_first_fn (fns));
7529 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7531 /* If lookup found a single function, mark it as used at this
7532 point. (If it lookup found multiple functions the one selected
7533 later by overload resolution will be marked as used at that
7535 if (BASELINK_P (baselink))
7536 fns = BASELINK_FUNCTIONS (baselink);
7537 if (!template_id_p && !really_overloaded_fn (fns))
7538 mark_used (OVL_CURRENT (fns));
7540 /* Add back the template arguments, if present. */
7541 if (BASELINK_P (baselink) && template_id_p)
7542 BASELINK_FUNCTIONS (baselink)
7543 = build_nt (TEMPLATE_ID_EXPR,
7544 BASELINK_FUNCTIONS (baselink),
7548 object_type = current_class_type;
7549 return adjust_result_of_qualified_name_lookup (baselink,
7554 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7555 true if the qualified-id will be a postfix-expression in-and-of
7556 itself; false if more of the postfix-expression follows the
7557 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7561 tsubst_qualified_id (tree qualified_id, tree args,
7562 tsubst_flags_t complain, tree in_decl,
7563 bool done, bool address_p)
7571 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7573 /* Figure out what name to look up. */
7574 name = TREE_OPERAND (qualified_id, 1);
7575 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7578 template_args = TREE_OPERAND (name, 1);
7580 template_args = tsubst_template_args (template_args, args,
7582 name = TREE_OPERAND (name, 0);
7586 is_template = false;
7587 template_args = NULL_TREE;
7590 /* Substitute into the qualifying scope. When there are no ARGS, we
7591 are just trying to simplify a non-dependent expression. In that
7592 case the qualifying scope may be dependent, and, in any case,
7593 substituting will not help. */
7594 scope = TREE_OPERAND (qualified_id, 0);
7597 scope = tsubst (scope, args, complain, in_decl);
7598 expr = tsubst_copy (name, args, complain, in_decl);
7603 if (dependent_type_p (scope))
7604 return build_nt (SCOPE_REF, scope, expr);
7606 if (!BASELINK_P (name) && !DECL_P (expr))
7608 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7609 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7610 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7612 if (complain & tf_error)
7614 error ("dependent-name %qE is parsed as a non-type, but "
7615 "instantiation yields a type", qualified_id);
7616 inform ("say %<typename %E%> if a type is meant", qualified_id);
7618 return error_mark_node;
7624 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7626 /* Remember that there was a reference to this entity. */
7630 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7632 if (complain & tf_error)
7633 qualified_name_lookup_error (scope,
7634 TREE_OPERAND (qualified_id, 1),
7636 return error_mark_node;
7640 expr = lookup_template_function (expr, template_args);
7642 if (expr == error_mark_node && complain & tf_error)
7643 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7645 else if (TYPE_P (scope))
7647 expr = (adjust_result_of_qualified_name_lookup
7648 (expr, scope, current_class_type));
7649 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7655 /* Like tsubst, but deals with expressions. This function just replaces
7656 template parms; to finish processing the resultant expression, use
7660 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7662 enum tree_code code;
7665 if (t == NULL_TREE || t == error_mark_node)
7668 code = TREE_CODE (t);
7673 r = retrieve_local_specialization (t);
7674 gcc_assert (r != NULL);
7683 if (DECL_TEMPLATE_PARM_P (t))
7684 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7685 /* There is no need to substitute into namespace-scope
7687 if (DECL_NAMESPACE_SCOPE_P (t))
7689 /* If ARGS is NULL, then T is known to be non-dependent. */
7690 if (args == NULL_TREE)
7691 return decl_constant_value (t);
7693 /* Unfortunately, we cannot just call lookup_name here.
7696 template <int I> int f() {
7698 struct S { void g() { E e = a; } };
7701 When we instantiate f<7>::S::g(), say, lookup_name is not
7702 clever enough to find f<7>::a. */
7704 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7705 /*entering_scope=*/0);
7707 for (v = TYPE_VALUES (enum_type);
7710 if (TREE_PURPOSE (v) == DECL_NAME (t))
7711 return TREE_VALUE (v);
7713 /* We didn't find the name. That should never happen; if
7714 name-lookup found it during preliminary parsing, we
7715 should find it again here during instantiation. */
7721 if (DECL_CONTEXT (t))
7725 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7726 /*entering_scope=*/1);
7727 if (ctx != DECL_CONTEXT (t))
7729 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7732 if (complain & tf_error)
7733 error ("using invalid field %qD", t);
7734 return error_mark_node;
7744 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7745 || local_variable_p (t))
7746 t = tsubst (t, args, complain, in_decl);
7751 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7754 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7755 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7756 args, complain, in_decl);
7757 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7758 return tsubst (t, args, complain, in_decl);
7759 else if (DECL_CLASS_SCOPE_P (t)
7760 && uses_template_parms (DECL_CONTEXT (t)))
7762 /* Template template argument like the following example need
7765 template <template <class> class TT> struct C {};
7766 template <class T> struct D {
7767 template <class U> struct E {};
7772 We are processing the template argument `E' in #1 for
7773 the template instantiation #2. Originally, `E' is a
7774 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7775 have to substitute this with one having context `D<int>'. */
7777 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7778 return lookup_field (context, DECL_NAME(t), 0, false);
7781 /* Ordinary template template argument. */
7785 case REINTERPRET_CAST_EXPR:
7786 case CONST_CAST_EXPR:
7787 case STATIC_CAST_EXPR:
7788 case DYNAMIC_CAST_EXPR:
7791 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7792 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7796 case TRUTH_NOT_EXPR:
7799 case CONVERT_EXPR: /* Unary + */
7808 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7809 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7816 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7817 name = TREE_OPERAND (t, 1);
7818 if (TREE_CODE (name) == BIT_NOT_EXPR)
7820 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7822 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7824 else if (TREE_CODE (name) == SCOPE_REF
7825 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7827 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7829 name = TREE_OPERAND (name, 1);
7830 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7832 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7833 name = build_nt (SCOPE_REF, base, name);
7835 else if (TREE_CODE (name) == BASELINK)
7836 name = tsubst_baselink (name,
7837 non_reference (TREE_TYPE (object)),
7841 name = tsubst_copy (name, args, complain, in_decl);
7842 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7848 case TRUNC_DIV_EXPR:
7850 case FLOOR_DIV_EXPR:
7851 case ROUND_DIV_EXPR:
7852 case EXACT_DIV_EXPR:
7856 case TRUNC_MOD_EXPR:
7857 case FLOOR_MOD_EXPR:
7858 case TRUTH_ANDIF_EXPR:
7859 case TRUTH_ORIF_EXPR:
7860 case TRUTH_AND_EXPR:
7879 case PREDECREMENT_EXPR:
7880 case PREINCREMENT_EXPR:
7881 case POSTDECREMENT_EXPR:
7882 case POSTINCREMENT_EXPR:
7884 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7885 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7888 return build_nt (code,
7889 tsubst_copy (TREE_OPERAND (t, 0), args,
7891 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7897 case PSEUDO_DTOR_EXPR:
7900 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7901 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7902 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7903 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7910 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7911 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7912 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7913 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7920 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7921 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7922 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7923 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7927 case TEMPLATE_ID_EXPR:
7929 /* Substituted template arguments */
7930 tree fn = TREE_OPERAND (t, 0);
7931 tree targs = TREE_OPERAND (t, 1);
7933 fn = tsubst_copy (fn, args, complain, in_decl);
7935 targs = tsubst_template_args (targs, args, complain, in_decl);
7937 return lookup_template_function (fn, targs);
7942 tree purpose, value, chain;
7944 if (t == void_list_node)
7947 purpose = TREE_PURPOSE (t);
7949 purpose = tsubst_copy (purpose, args, complain, in_decl);
7950 value = TREE_VALUE (t);
7952 value = tsubst_copy (value, args, complain, in_decl);
7953 chain = TREE_CHAIN (t);
7954 if (chain && chain != void_type_node)
7955 chain = tsubst_copy (chain, args, complain, in_decl);
7956 if (purpose == TREE_PURPOSE (t)
7957 && value == TREE_VALUE (t)
7958 && chain == TREE_CHAIN (t))
7960 return tree_cons (purpose, value, chain);
7967 case TEMPLATE_TYPE_PARM:
7968 case TEMPLATE_TEMPLATE_PARM:
7969 case BOUND_TEMPLATE_TEMPLATE_PARM:
7970 case TEMPLATE_PARM_INDEX:
7972 case REFERENCE_TYPE:
7978 case UNBOUND_CLASS_TEMPLATE:
7981 return tsubst (t, args, complain, in_decl);
7983 case IDENTIFIER_NODE:
7984 if (IDENTIFIER_TYPENAME_P (t))
7986 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7987 return mangle_conv_op_name_for_type (new_type);
7994 r = build_constructor
7995 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7996 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7997 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8002 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8004 tsubst (TREE_TYPE (t), args, complain, in_decl));
8006 case CLEANUP_POINT_EXPR:
8007 /* We shouldn't have built any of these during initial template
8008 generation. Instead, they should be built during instantiation
8009 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8017 /* Like tsubst_copy for expressions, etc. but also does semantic
8021 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8025 if (t == NULL_TREE || t == error_mark_node)
8028 if (EXPR_HAS_LOCATION (t))
8029 input_location = EXPR_LOCATION (t);
8030 if (STATEMENT_CODE_P (TREE_CODE (t)))
8031 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8033 switch (TREE_CODE (t))
8035 case STATEMENT_LIST:
8037 tree_stmt_iterator i;
8038 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8039 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8043 case CTOR_INITIALIZER:
8044 finish_mem_initializers (tsubst_initializer_list
8045 (TREE_OPERAND (t, 0), args));
8049 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8050 args, complain, in_decl));
8054 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8055 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8056 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8058 finish_expr_stmt (tmp);
8062 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8063 args, complain, in_decl));
8071 decl = DECL_EXPR_DECL (t);
8072 if (TREE_CODE (decl) == LABEL_DECL)
8073 finish_label_decl (DECL_NAME (decl));
8074 else if (TREE_CODE (decl) == USING_DECL)
8076 tree scope = DECL_INITIAL (decl);
8077 tree name = DECL_NAME (decl);
8080 scope = tsubst_expr (scope, args, complain, in_decl);
8081 decl = lookup_qualified_name (scope, name,
8082 /*is_type_p=*/false,
8083 /*complain=*/false);
8084 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8085 qualified_name_lookup_error (scope, name, decl);
8087 do_local_using_decl (decl, scope, name);
8091 init = DECL_INITIAL (decl);
8092 decl = tsubst (decl, args, complain, in_decl);
8093 if (decl != error_mark_node)
8096 DECL_INITIAL (decl) = error_mark_node;
8097 /* By marking the declaration as instantiated, we avoid
8098 trying to instantiate it. Since instantiate_decl can't
8099 handle local variables, and since we've already done
8100 all that needs to be done, that's the right thing to
8102 if (TREE_CODE (decl) == VAR_DECL)
8103 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8104 if (TREE_CODE (decl) == VAR_DECL
8105 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8106 /* Anonymous aggregates are a special case. */
8107 finish_anon_union (decl);
8110 maybe_push_decl (decl);
8111 if (TREE_CODE (decl) == VAR_DECL
8112 && DECL_PRETTY_FUNCTION_P (decl))
8114 /* For __PRETTY_FUNCTION__ we have to adjust the
8116 const char *const name
8117 = cxx_printable_name (current_function_decl, 2);
8118 init = cp_fname_init (name, &TREE_TYPE (decl));
8121 init = tsubst_expr (init, args, complain, in_decl);
8122 cp_finish_decl (decl, init, NULL_TREE, 0);
8127 /* A DECL_EXPR can also be used as an expression, in the condition
8128 clause of an if/for/while construct. */
8133 stmt = begin_for_stmt ();
8134 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8135 finish_for_init_stmt (stmt);
8136 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8137 finish_for_cond (tmp, stmt);
8138 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8139 finish_for_expr (tmp, stmt);
8140 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8141 finish_for_stmt (stmt);
8145 stmt = begin_while_stmt ();
8146 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8147 finish_while_stmt_cond (tmp, stmt);
8148 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8149 finish_while_stmt (stmt);
8153 stmt = begin_do_stmt ();
8154 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8155 finish_do_body (stmt);
8156 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8157 finish_do_stmt (tmp, stmt);
8161 stmt = begin_if_stmt ();
8162 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8163 finish_if_stmt_cond (tmp, stmt);
8164 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8165 finish_then_clause (stmt);
8167 if (ELSE_CLAUSE (t))
8169 begin_else_clause (stmt);
8170 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8171 finish_else_clause (stmt);
8174 finish_if_stmt (stmt);
8178 if (BIND_EXPR_BODY_BLOCK (t))
8179 stmt = begin_function_body ();
8181 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8182 ? BCS_TRY_BLOCK : 0);
8184 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8186 if (BIND_EXPR_BODY_BLOCK (t))
8187 finish_function_body (stmt);
8189 finish_compound_stmt (stmt);
8193 finish_break_stmt ();
8197 finish_continue_stmt ();
8201 stmt = begin_switch_stmt ();
8202 tmp = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
8203 finish_switch_cond (tmp, stmt);
8204 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
8205 finish_switch_stmt (stmt);
8208 case CASE_LABEL_EXPR:
8209 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8210 tsubst_expr (CASE_HIGH (t), args, complain,
8215 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8219 tmp = GOTO_DESTINATION (t);
8220 if (TREE_CODE (tmp) != LABEL_DECL)
8221 /* Computed goto's must be tsubst'd into. On the other hand,
8222 non-computed gotos must not be; the identifier in question
8223 will have no binding. */
8224 tmp = tsubst_expr (tmp, args, complain, in_decl);
8226 tmp = DECL_NAME (tmp);
8227 finish_goto_stmt (tmp);
8231 tmp = finish_asm_stmt
8232 (ASM_VOLATILE_P (t),
8233 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8234 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8235 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8236 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8238 tree asm_expr = tmp;
8239 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8240 asm_expr = TREE_OPERAND (asm_expr, 0);
8241 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8248 stmt = begin_try_block ();
8249 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8250 finish_cleanup_try_block (stmt);
8251 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8257 if (FN_TRY_BLOCK_P (t))
8258 stmt = begin_function_try_block ();
8260 stmt = begin_try_block ();
8262 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8264 if (FN_TRY_BLOCK_P (t))
8265 finish_function_try_block (stmt);
8267 finish_try_block (stmt);
8269 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8270 if (FN_TRY_BLOCK_P (t))
8271 finish_function_handler_sequence (stmt);
8273 finish_handler_sequence (stmt);
8281 stmt = begin_handler ();
8282 if (HANDLER_PARMS (t))
8284 decl = HANDLER_PARMS (t);
8285 decl = tsubst (decl, args, complain, in_decl);
8286 /* Prevent instantiate_decl from trying to instantiate
8287 this variable. We've already done all that needs to be
8289 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8293 finish_handler_parms (decl, stmt);
8294 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8295 finish_handler (stmt);
8300 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8304 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8306 return tsubst_copy_and_build (t, args, complain, in_decl,
8307 /*function_p=*/false);
8313 /* T is a postfix-expression that is not being used in a function
8314 call. Return the substituted version of T. */
8317 tsubst_non_call_postfix_expression (tree t, tree args,
8318 tsubst_flags_t complain,
8321 if (TREE_CODE (t) == SCOPE_REF)
8322 t = tsubst_qualified_id (t, args, complain, in_decl,
8323 /*done=*/false, /*address_p=*/false);
8325 t = tsubst_copy_and_build (t, args, complain, in_decl,
8326 /*function_p=*/false);
8331 /* Like tsubst but deals with expressions and performs semantic
8332 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8335 tsubst_copy_and_build (tree t,
8337 tsubst_flags_t complain,
8341 #define RECUR(NODE) \
8342 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8346 if (t == NULL_TREE || t == error_mark_node)
8349 switch (TREE_CODE (t))
8354 case IDENTIFIER_NODE:
8358 tree qualifying_class;
8359 bool non_integral_constant_expression_p;
8360 const char *error_msg;
8362 if (IDENTIFIER_TYPENAME_P (t))
8364 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8365 t = mangle_conv_op_name_for_type (new_type);
8368 /* Look up the name. */
8369 decl = lookup_name (t, 0);
8371 /* By convention, expressions use ERROR_MARK_NODE to indicate
8372 failure, not NULL_TREE. */
8373 if (decl == NULL_TREE)
8374 decl = error_mark_node;
8376 decl = finish_id_expression (t, decl, NULL_TREE,
8379 /*integral_constant_expression_p=*/false,
8380 /*allow_non_integral_constant_expression_p=*/false,
8381 &non_integral_constant_expression_p,
8385 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8386 decl = unqualified_name_lookup_error (decl);
8390 case TEMPLATE_ID_EXPR:
8393 tree template = RECUR (TREE_OPERAND (t, 0));
8394 tree targs = TREE_OPERAND (t, 1);
8397 targs = tsubst_template_args (targs, args, complain, in_decl);
8399 if (TREE_CODE (template) == COMPONENT_REF)
8401 object = TREE_OPERAND (template, 0);
8402 template = TREE_OPERAND (template, 1);
8406 template = lookup_template_function (template, targs);
8409 return build3 (COMPONENT_REF, TREE_TYPE (template),
8410 object, template, NULL_TREE);
8417 tree r = RECUR (TREE_OPERAND (t, 0));
8419 if (REFERENCE_REF_P (t))
8421 /* A type conversion to reference type will be enclosed in
8422 such an indirect ref, but the substitution of the cast
8423 will have also added such an indirect ref. */
8424 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8425 r = convert_from_reference (r);
8428 r = build_x_indirect_ref (r, "unary *");
8434 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8435 RECUR (TREE_OPERAND (t, 0)));
8438 return build_functional_cast
8439 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8440 RECUR (TREE_OPERAND (t, 0)));
8442 case REINTERPRET_CAST_EXPR:
8443 return build_reinterpret_cast
8444 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8445 RECUR (TREE_OPERAND (t, 0)));
8447 case CONST_CAST_EXPR:
8448 return build_const_cast
8449 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8450 RECUR (TREE_OPERAND (t, 0)));
8452 case DYNAMIC_CAST_EXPR:
8453 return build_dynamic_cast
8454 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8455 RECUR (TREE_OPERAND (t, 0)));
8457 case STATIC_CAST_EXPR:
8458 return build_static_cast
8459 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8460 RECUR (TREE_OPERAND (t, 0)));
8462 case POSTDECREMENT_EXPR:
8463 case POSTINCREMENT_EXPR:
8464 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8465 args, complain, in_decl);
8466 return build_x_unary_op (TREE_CODE (t), op1);
8468 case PREDECREMENT_EXPR:
8469 case PREINCREMENT_EXPR:
8473 case TRUTH_NOT_EXPR:
8474 case CONVERT_EXPR: /* Unary + */
8477 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8480 op1 = TREE_OPERAND (t, 0);
8481 if (TREE_CODE (op1) == SCOPE_REF)
8482 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8483 /*done=*/true, /*address_p=*/true);
8485 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8487 if (TREE_CODE (op1) == LABEL_DECL)
8488 return finish_label_address_expr (DECL_NAME (op1));
8489 return build_x_unary_op (ADDR_EXPR, op1);
8494 case TRUNC_DIV_EXPR:
8496 case FLOOR_DIV_EXPR:
8497 case ROUND_DIV_EXPR:
8498 case EXACT_DIV_EXPR:
8502 case TRUNC_MOD_EXPR:
8503 case FLOOR_MOD_EXPR:
8504 case TRUTH_ANDIF_EXPR:
8505 case TRUTH_ORIF_EXPR:
8506 case TRUTH_AND_EXPR:
8522 return build_x_binary_op
8524 RECUR (TREE_OPERAND (t, 0)),
8525 RECUR (TREE_OPERAND (t, 1)),
8526 /*overloaded_p=*/NULL);
8529 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8530 /*address_p=*/false);
8533 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8536 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)),
8537 NULL_TREE, NULL_TREE);
8539 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8540 args, complain, in_decl);
8541 /* Remember that there was a reference to this entity. */
8544 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8548 op1 = TREE_OPERAND (t, 0);
8551 /* When there are no ARGS, we are trying to evaluate a
8552 non-dependent expression from the parser. Trying to do
8553 the substitutions may not work. */
8555 op1 = TREE_TYPE (op1);
8564 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8566 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8570 tree r = build_x_modify_expr
8571 (RECUR (TREE_OPERAND (t, 0)),
8572 TREE_CODE (TREE_OPERAND (t, 1)),
8573 RECUR (TREE_OPERAND (t, 2)));
8574 /* TREE_NO_WARNING must be set if either the expression was
8575 parenthesized or it uses an operator such as >>= rather
8576 than plain assignment. In the former case, it was already
8577 set and must be copied. In the latter case,
8578 build_x_modify_expr sets it and it must not be reset
8580 if (TREE_NO_WARNING (t))
8581 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8586 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8587 args, complain, in_decl);
8588 /* Remember that there was a reference to this entity. */
8591 return build_x_arrow (op1);
8595 (RECUR (TREE_OPERAND (t, 0)),
8596 RECUR (TREE_OPERAND (t, 1)),
8597 RECUR (TREE_OPERAND (t, 2)),
8598 RECUR (TREE_OPERAND (t, 3)),
8599 NEW_EXPR_USE_GLOBAL (t));
8602 return delete_sanity
8603 (RECUR (TREE_OPERAND (t, 0)),
8604 RECUR (TREE_OPERAND (t, 1)),
8605 DELETE_EXPR_USE_VEC (t),
8606 DELETE_EXPR_USE_GLOBAL (t));
8609 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8610 RECUR (TREE_OPERAND (t, 1)));
8619 function = TREE_OPERAND (t, 0);
8620 /* When we parsed the expression, we determined whether or
8621 not Koenig lookup should be performed. */
8622 koenig_p = KOENIG_LOOKUP_P (t);
8623 if (TREE_CODE (function) == SCOPE_REF)
8626 function = tsubst_qualified_id (function, args, complain, in_decl,
8628 /*address_p=*/false);
8632 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8633 && (TREE_CODE (TREE_OPERAND (function, 1))
8635 function = tsubst_copy_and_build (function, args, complain,
8638 if (BASELINK_P (function))
8642 call_args = RECUR (TREE_OPERAND (t, 1));
8644 /* We do not perform argument-dependent lookup if normal
8645 lookup finds a non-function, in accordance with the
8646 expected resolution of DR 218. */
8648 && ((is_overloaded_fn (function)
8649 /* If lookup found a member function, the Koenig lookup is
8650 not appropriate, even if an unqualified-name was used
8651 to denote the function. */
8652 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8653 || TREE_CODE (function) == IDENTIFIER_NODE))
8654 function = perform_koenig_lookup (function, call_args);
8656 if (TREE_CODE (function) == IDENTIFIER_NODE)
8658 unqualified_name_lookup_error (function);
8659 return error_mark_node;
8662 /* Remember that there was a reference to this entity. */
8663 if (DECL_P (function))
8664 mark_used (function);
8666 if (TREE_CODE (function) == OFFSET_REF)
8667 return build_offset_ref_call_from_tree (function, call_args);
8668 if (TREE_CODE (function) == COMPONENT_REF)
8670 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8671 return finish_call_expr (function, call_args,
8672 /*disallow_virtual=*/false,
8673 /*koenig_p=*/false);
8675 return (build_new_method_call
8676 (TREE_OPERAND (function, 0),
8677 TREE_OPERAND (function, 1),
8678 call_args, NULL_TREE,
8679 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8681 return finish_call_expr (function, call_args,
8682 /*disallow_virtual=*/qualified_p,
8687 return build_x_conditional_expr
8688 (RECUR (TREE_OPERAND (t, 0)),
8689 RECUR (TREE_OPERAND (t, 1)),
8690 RECUR (TREE_OPERAND (t, 2)));
8692 case PSEUDO_DTOR_EXPR:
8693 return finish_pseudo_destructor_expr
8694 (RECUR (TREE_OPERAND (t, 0)),
8695 RECUR (TREE_OPERAND (t, 1)),
8696 RECUR (TREE_OPERAND (t, 2)));
8700 tree purpose, value, chain;
8702 if (t == void_list_node)
8705 purpose = TREE_PURPOSE (t);
8707 purpose = RECUR (purpose);
8708 value = TREE_VALUE (t);
8710 value = RECUR (value);
8711 chain = TREE_CHAIN (t);
8712 if (chain && chain != void_type_node)
8713 chain = RECUR (chain);
8714 if (purpose == TREE_PURPOSE (t)
8715 && value == TREE_VALUE (t)
8716 && chain == TREE_CHAIN (t))
8718 return tree_cons (purpose, value, chain);
8726 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8727 args, complain, in_decl);
8728 /* Remember that there was a reference to this entity. */
8729 if (DECL_P (object))
8732 member = TREE_OPERAND (t, 1);
8733 if (BASELINK_P (member))
8734 member = tsubst_baselink (member,
8735 non_reference (TREE_TYPE (object)),
8736 args, complain, in_decl);
8738 member = tsubst_copy (member, args, complain, in_decl);
8740 if (member == error_mark_node)
8741 return error_mark_node;
8742 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8744 if (TREE_CODE (member) == BIT_NOT_EXPR)
8745 return finish_pseudo_destructor_expr (object,
8747 TREE_TYPE (object));
8748 else if (TREE_CODE (member) == SCOPE_REF
8749 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8750 return finish_pseudo_destructor_expr (object,
8752 TREE_TYPE (object));
8754 else if (TREE_CODE (member) == SCOPE_REF
8755 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8760 /* Lookup the template functions now that we know what the
8762 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8763 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8764 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8765 /*is_type_p=*/false,
8766 /*complain=*/false);
8767 if (BASELINK_P (member))
8769 BASELINK_FUNCTIONS (member)
8770 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8772 member = (adjust_result_of_qualified_name_lookup
8773 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8774 TREE_TYPE (object)));
8778 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8780 return error_mark_node;
8783 else if (TREE_CODE (member) == SCOPE_REF
8784 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8785 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8787 if (complain & tf_error)
8789 if (TYPE_P (TREE_OPERAND (member, 0)))
8790 error ("%qT is not a class or namespace",
8791 TREE_OPERAND (member, 0));
8793 error ("%qD is not a class or namespace",
8794 TREE_OPERAND (member, 0));
8796 return error_mark_node;
8798 else if (TREE_CODE (member) == FIELD_DECL)
8799 return finish_non_static_data_member (member, object, NULL_TREE);
8801 return finish_class_member_access_expr (object, member);
8806 (RECUR (TREE_OPERAND (t, 0)));
8812 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8815 /* digest_init will do the wrong thing if we let it. */
8816 if (type && TYPE_PTRMEMFUNC_P (type))
8820 /* We do not want to process the purpose of aggregate
8821 initializers as they are identifier nodes which will be
8822 looked up by digest_init. */
8823 purpose_p = !(type && IS_AGGR_TYPE (type));
8824 for (elts = CONSTRUCTOR_ELTS (t);
8826 elts = TREE_CHAIN (elts))
8828 tree purpose = TREE_PURPOSE (elts);
8829 tree value = TREE_VALUE (elts);
8831 if (purpose && purpose_p)
8832 purpose = RECUR (purpose);
8833 value = RECUR (value);
8834 r = tree_cons (purpose, value, r);
8837 r = build_constructor (NULL_TREE, nreverse (r));
8838 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8841 return digest_init (type, r, 0);
8847 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8848 if (TYPE_P (operand_0))
8849 return get_typeid (operand_0);
8850 return build_typeid (operand_0);
8860 tree r = tsubst_copy (t, args, complain, in_decl);
8862 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8863 /* If the original type was a reference, we'll be wrapped in
8864 the appropriate INDIRECT_REF. */
8865 r = convert_from_reference (r);
8870 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8871 tsubst_copy (TREE_TYPE (t), args, complain,
8875 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8879 tree old_stmt_expr = cur_stmt_expr;
8880 tree stmt_expr = begin_stmt_expr ();
8882 cur_stmt_expr = stmt_expr;
8883 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8884 stmt_expr = finish_stmt_expr (stmt_expr, false);
8885 cur_stmt_expr = old_stmt_expr;
8891 t = tsubst_copy (t, args, complain, in_decl);
8892 /* As in finish_id_expression, we resolve enumeration constants
8893 to their underlying values. */
8894 if (TREE_CODE (t) == CONST_DECL)
8895 return DECL_INITIAL (t);
8899 return tsubst_copy (t, args, complain, in_decl);
8905 /* Verify that the instantiated ARGS are valid. For type arguments,
8906 make sure that the type's linkage is ok. For non-type arguments,
8907 make sure they are constants if they are integral or enumerations.
8908 Emit an error under control of COMPLAIN, and return TRUE on error. */
8911 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8913 int ix, len = DECL_NTPARMS (tmpl);
8914 bool result = false;
8916 for (ix = 0; ix != len; ix++)
8918 tree t = TREE_VEC_ELT (args, ix);
8922 /* [basic.link]: A name with no linkage (notably, the name
8923 of a class or enumeration declared in a local scope)
8924 shall not be used to declare an entity with linkage.
8925 This implies that names with no linkage cannot be used as
8926 template arguments. */
8927 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8931 if (!(complain & tf_error))
8933 else if (TYPE_ANONYMOUS_P (nt))
8934 error ("%qT uses anonymous type", t);
8936 error ("%qT uses local type %qT", t, nt);
8939 /* In order to avoid all sorts of complications, we do not
8940 allow variably-modified types as template arguments. */
8941 else if (variably_modified_type_p (t, NULL_TREE))
8943 if (complain & tf_error)
8944 error ("%qT is a variably modified type", t);
8948 /* A non-type argument of integral or enumerated type must be a
8950 else if (TREE_TYPE (t)
8951 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8952 && !TREE_CONSTANT (t))
8954 if (complain & tf_error)
8955 error ("integral expression %qE is not constant", t);
8959 if (result && complain & tf_error)
8960 error (" trying to instantiate %qD", tmpl);
8964 /* Instantiate the indicated variable or function template TMPL with
8965 the template arguments in TARG_PTR. */
8968 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8974 if (tmpl == error_mark_node)
8975 return error_mark_node;
8977 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
8979 /* If this function is a clone, handle it specially. */
8980 if (DECL_CLONED_FUNCTION_P (tmpl))
8985 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8987 if (spec == error_mark_node)
8988 return error_mark_node;
8990 /* Look for the clone. */
8991 FOR_EACH_CLONE (clone, spec)
8992 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8994 /* We should always have found the clone by now. */
8999 /* Check to see if we already have this specialization. */
9000 spec = retrieve_specialization (tmpl, targ_ptr,
9001 /*class_specializations_p=*/false);
9002 if (spec != NULL_TREE)
9005 gen_tmpl = most_general_template (tmpl);
9006 if (tmpl != gen_tmpl)
9008 /* The TMPL is a partial instantiation. To get a full set of
9009 arguments we must add the arguments used to perform the
9010 partial instantiation. */
9011 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9014 /* Check to see if we already have this specialization. */
9015 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9016 /*class_specializations_p=*/false);
9017 if (spec != NULL_TREE)
9021 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9023 return error_mark_node;
9025 /* We are building a FUNCTION_DECL, during which the access of its
9026 parameters and return types have to be checked. However this
9027 FUNCTION_DECL which is the desired context for access checking
9028 is not built yet. We solve this chicken-and-egg problem by
9029 deferring all checks until we have the FUNCTION_DECL. */
9030 push_deferring_access_checks (dk_deferred);
9032 /* Substitute template parameters. */
9033 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9034 targ_ptr, complain, gen_tmpl);
9036 /* Now we know the specialization, compute access previously
9038 push_access_scope (fndecl);
9039 perform_deferred_access_checks ();
9040 pop_access_scope (fndecl);
9041 pop_deferring_access_checks ();
9043 /* The DECL_TI_TEMPLATE should always be the immediate parent
9044 template, not the most general template. */
9045 DECL_TI_TEMPLATE (fndecl) = tmpl;
9047 /* If we've just instantiated the main entry point for a function,
9048 instantiate all the alternate entry points as well. We do this
9049 by cloning the instantiation of the main entry point, not by
9050 instantiating the template clones. */
9051 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9052 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9057 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9058 arguments that are being used when calling it. TARGS is a vector
9059 into which the deduced template arguments are placed.
9061 Return zero for success, 2 for an incomplete match that doesn't resolve
9062 all the types, and 1 for complete failure. An error message will be
9063 printed only for an incomplete match.
9065 If FN is a conversion operator, or we are trying to produce a specific
9066 specialization, RETURN_TYPE is the return type desired.
9068 The EXPLICIT_TARGS are explicit template arguments provided via a
9071 The parameter STRICT is one of:
9074 We are deducing arguments for a function call, as in
9078 We are deducing arguments for a conversion function, as in
9082 We are deducing arguments when doing an explicit instantiation
9083 as in [temp.explicit], when determining an explicit specialization
9084 as in [temp.expl.spec], or when taking the address of a function
9085 template, as in [temp.deduct.funcaddr].
9088 We are deducing arguments when calculating the partial
9089 ordering between specializations of function or class
9090 templates, as in [temp.func.order] and [temp.class.order].
9092 LEN is the number of parms to consider before returning success, or -1
9093 for all. This is used in partial ordering to avoid comparing parms for
9094 which no actual argument was passed, since they are not considered in
9095 overload resolution (and are explicitly excluded from consideration in
9096 partial ordering in [temp.func.order]/6). */
9099 fn_type_unification (tree fn,
9100 tree explicit_targs,
9104 unification_kind_t strict,
9111 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9113 fntype = TREE_TYPE (fn);
9118 The specified template arguments must match the template
9119 parameters in kind (i.e., type, nontype, template), and there
9120 must not be more arguments than there are parameters;
9121 otherwise type deduction fails.
9123 Nontype arguments must match the types of the corresponding
9124 nontype template parameters, or must be convertible to the
9125 types of the corresponding nontype parameters as specified in
9126 _temp.arg.nontype_, otherwise type deduction fails.
9128 All references in the function type of the function template
9129 to the corresponding template parameters are replaced by the
9130 specified template argument values. If a substitution in a
9131 template parameter or in the function type of the function
9132 template results in an invalid type, type deduction fails. */
9134 tree converted_args;
9138 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9139 explicit_targs, NULL_TREE, tf_none,
9140 /*require_all_arguments=*/0));
9141 if (converted_args == error_mark_node)
9144 /* Substitute the explicit args into the function type. This is
9145 necessary so that, for instance, explicitly declared function
9146 arguments can match null pointed constants. If we were given
9147 an incomplete set of explicit args, we must not do semantic
9148 processing during substitution as we could create partial
9150 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9151 processing_template_decl += incomplete;
9152 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9153 processing_template_decl -= incomplete;
9155 if (fntype == error_mark_node)
9158 /* Place the explicitly specified arguments in TARGS. */
9159 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9160 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9163 parms = TYPE_ARG_TYPES (fntype);
9164 /* Never do unification on the 'this' parameter. */
9165 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9166 parms = TREE_CHAIN (parms);
9170 /* We've been given a return type to match, prepend it. */
9171 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9172 args = tree_cons (NULL_TREE, return_type, args);
9177 /* We allow incomplete unification without an error message here
9178 because the standard doesn't seem to explicitly prohibit it. Our
9179 callers must be ready to deal with unification failures in any
9181 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9182 targs, parms, args, /*subr=*/0,
9183 strict, /*allow_incomplete*/1, len);
9186 /* All is well so far. Now, check:
9190 When all template arguments have been deduced, all uses of
9191 template parameters in nondeduced contexts are replaced with
9192 the corresponding deduced argument values. If the
9193 substitution results in an invalid type, as described above,
9194 type deduction fails. */
9195 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9202 /* Adjust types before performing type deduction, as described in
9203 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9204 sections are symmetric. PARM is the type of a function parameter
9205 or the return type of the conversion function. ARG is the type of
9206 the argument passed to the call, or the type of the value
9207 initialized with the result of the conversion function. */
9210 maybe_adjust_types_for_deduction (unification_kind_t strict,
9223 /* Swap PARM and ARG throughout the remainder of this
9224 function; the handling is precisely symmetric since PARM
9225 will initialize ARG rather than vice versa. */
9233 /* There is nothing to do in this case. */
9237 /* DR 214. [temp.func.order] is underspecified, and leads to no
9238 ordering between things like `T *' and `T const &' for `U *'.
9239 The former has T=U and the latter T=U*. The former looks more
9240 specialized and John Spicer considers it well-formed (the EDG
9241 compiler accepts it).
9243 John also confirms that deduction should proceed as in a function
9244 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
9245 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
9246 to an actual call can have such a type.
9248 If both ARG and PARM are REFERENCE_TYPE, we change neither.
9249 If only ARG is a REFERENCE_TYPE, we look through that and then
9250 proceed as with DEDUCE_CALL (which could further convert it). */
9251 if (TREE_CODE (*arg) == REFERENCE_TYPE)
9253 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9255 *arg = TREE_TYPE (*arg);
9262 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9264 /* [temp.deduct.call]
9266 If P is not a reference type:
9268 --If A is an array type, the pointer type produced by the
9269 array-to-pointer standard conversion (_conv.array_) is
9270 used in place of A for type deduction; otherwise,
9272 --If A is a function type, the pointer type produced by
9273 the function-to-pointer standard conversion
9274 (_conv.func_) is used in place of A for type deduction;
9277 --If A is a cv-qualified type, the top level
9278 cv-qualifiers of A's type are ignored for type
9280 if (TREE_CODE (*arg) == ARRAY_TYPE)
9281 *arg = build_pointer_type (TREE_TYPE (*arg));
9282 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9283 *arg = build_pointer_type (*arg);
9285 *arg = TYPE_MAIN_VARIANT (*arg);
9288 /* [temp.deduct.call]
9290 If P is a cv-qualified type, the top level cv-qualifiers
9291 of P's type are ignored for type deduction. If P is a
9292 reference type, the type referred to by P is used for
9294 *parm = TYPE_MAIN_VARIANT (*parm);
9295 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9297 *parm = TREE_TYPE (*parm);
9298 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9301 /* DR 322. For conversion deduction, remove a reference type on parm
9302 too (which has been swapped into ARG). */
9303 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9304 *arg = TREE_TYPE (*arg);
9309 /* Most parms like fn_type_unification.
9311 If SUBR is 1, we're being called recursively (to unify the
9312 arguments of a function or method parameter of a function
9316 type_unification_real (tree tparms,
9321 unification_kind_t strict,
9322 int allow_incomplete,
9327 int ntparms = TREE_VEC_LENGTH (tparms);
9329 int saw_undeduced = 0;
9333 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9334 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9335 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9336 gcc_assert (ntparms > 0);
9341 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9342 | UNIFY_ALLOW_DERIVED);
9346 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9350 sub_strict = UNIFY_ALLOW_NONE;
9354 sub_strict = UNIFY_ALLOW_NONE;
9370 && parms != void_list_node
9372 && args != void_list_node)
9374 parm = TREE_VALUE (parms);
9375 parms = TREE_CHAIN (parms);
9376 arg = TREE_VALUE (args);
9377 args = TREE_CHAIN (args);
9379 if (arg == error_mark_node)
9381 if (arg == unknown_type_node)
9382 /* We can't deduce anything from this, but we might get all the
9383 template args from other function args. */
9386 /* Conversions will be performed on a function argument that
9387 corresponds with a function parameter that contains only
9388 non-deducible template parameters and explicitly specified
9389 template parameters. */
9390 if (!uses_template_parms (parm))
9395 type = TREE_TYPE (arg);
9399 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
9401 if (same_type_p (parm, type))
9405 /* It might work; we shouldn't check now, because we might
9406 get into infinite recursion. Overload resolution will
9415 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9416 if (type_unknown_p (arg))
9418 /* [temp.deduct.type] A template-argument can be deduced from
9419 a pointer to function or pointer to member function
9420 argument if the set of overloaded functions does not
9421 contain function templates and at most one of a set of
9422 overloaded functions provides a unique match. */
9424 if (resolve_overloaded_unification
9425 (tparms, targs, parm, arg, strict, sub_strict)
9430 arg = TREE_TYPE (arg);
9431 if (arg == error_mark_node)
9436 int arg_strict = sub_strict;
9439 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9441 if (unify (tparms, targs, parm, arg, arg_strict))
9445 /* Are we done with the interesting parms? */
9449 /* Fail if we've reached the end of the parm list, and more args
9450 are present, and the parm list isn't variadic. */
9451 if (args && args != void_list_node && parms == void_list_node)
9453 /* Fail if parms are left and they don't have default values. */
9455 && parms != void_list_node
9456 && TREE_PURPOSE (parms) == NULL_TREE)
9461 for (i = 0; i < ntparms; i++)
9462 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
9464 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9466 /* If this is an undeduced nontype parameter that depends on
9467 a type parameter, try another pass; its type may have been
9468 deduced from a later argument than the one from which
9469 this parameter can be deduced. */
9470 if (TREE_CODE (tparm) == PARM_DECL
9471 && uses_template_parms (TREE_TYPE (tparm))
9472 && !saw_undeduced++)
9475 if (!allow_incomplete)
9476 error ("incomplete type unification");
9482 /* Subroutine of type_unification_real. Args are like the variables at the
9483 call site. ARG is an overloaded function (or template-id); we try
9484 deducing template args from each of the overloads, and if only one
9485 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9488 resolve_overloaded_unification (tree tparms,
9492 unification_kind_t strict,
9495 tree tempargs = copy_node (targs);
9499 if (TREE_CODE (arg) == ADDR_EXPR)
9501 arg = TREE_OPERAND (arg, 0);
9507 if (TREE_CODE (arg) == COMPONENT_REF)
9508 /* Handle `&x' where `x' is some static or non-static member
9510 arg = TREE_OPERAND (arg, 1);
9512 if (TREE_CODE (arg) == OFFSET_REF)
9513 arg = TREE_OPERAND (arg, 1);
9515 /* Strip baselink information. */
9516 if (BASELINK_P (arg))
9517 arg = BASELINK_FUNCTIONS (arg);
9519 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9521 /* If we got some explicit template args, we need to plug them into
9522 the affected templates before we try to unify, in case the
9523 explicit args will completely resolve the templates in question. */
9525 tree expl_subargs = TREE_OPERAND (arg, 1);
9526 arg = TREE_OPERAND (arg, 0);
9528 for (; arg; arg = OVL_NEXT (arg))
9530 tree fn = OVL_CURRENT (arg);
9533 if (TREE_CODE (fn) != TEMPLATE_DECL)
9536 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
9540 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9541 good += try_one_overload (tparms, targs, tempargs, parm,
9542 elem, strict, sub_strict, addr_p);
9548 gcc_assert (TREE_CODE (arg) == OVERLOAD
9549 || TREE_CODE (arg) == FUNCTION_DECL);
9551 for (; arg; arg = OVL_NEXT (arg))
9552 good += try_one_overload (tparms, targs, tempargs, parm,
9553 TREE_TYPE (OVL_CURRENT (arg)),
9554 strict, sub_strict, addr_p);
9557 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9558 to function or pointer to member function argument if the set of
9559 overloaded functions does not contain function templates and at most
9560 one of a set of overloaded functions provides a unique match.
9562 So if we found multiple possibilities, we return success but don't
9567 int i = TREE_VEC_LENGTH (targs);
9569 if (TREE_VEC_ELT (tempargs, i))
9570 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9578 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9579 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9580 different overloads deduce different arguments for a given parm.
9581 ADDR_P is true if the expression for which deduction is being
9582 performed was of the form "& fn" rather than simply "fn".
9584 Returns 1 on success. */
9587 try_one_overload (tree tparms,
9592 unification_kind_t strict,
9600 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9601 to function or pointer to member function argument if the set of
9602 overloaded functions does not contain function templates and at most
9603 one of a set of overloaded functions provides a unique match.
9605 So if this is a template, just return success. */
9607 if (uses_template_parms (arg))
9610 if (TREE_CODE (arg) == METHOD_TYPE)
9611 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9613 arg = build_pointer_type (arg);
9615 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9617 /* We don't copy orig_targs for this because if we have already deduced
9618 some template args from previous args, unify would complain when we
9619 try to deduce a template parameter for the same argument, even though
9620 there isn't really a conflict. */
9621 nargs = TREE_VEC_LENGTH (targs);
9622 tempargs = make_tree_vec (nargs);
9624 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9627 /* First make sure we didn't deduce anything that conflicts with
9628 explicitly specified args. */
9629 for (i = nargs; i--; )
9631 tree elt = TREE_VEC_ELT (tempargs, i);
9632 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9634 if (elt == NULL_TREE)
9636 else if (uses_template_parms (elt))
9638 /* Since we're unifying against ourselves, we will fill in template
9639 args used in the function parm list with our own template parms.
9641 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9644 else if (oldelt && ! template_args_equal (oldelt, elt))
9648 for (i = nargs; i--; )
9650 tree elt = TREE_VEC_ELT (tempargs, i);
9653 TREE_VEC_ELT (targs, i) = elt;
9659 /* Verify that nondeduce template argument agrees with the type
9660 obtained from argument deduction. Return nonzero if the
9665 struct A { typedef int X; };
9666 template <class T, class U> struct C {};
9667 template <class T> struct C<T, typename T::X> {};
9669 Then with the instantiation `C<A, int>', we can deduce that
9670 `T' is `A' but unify () does not check whether `typename T::X'
9671 is `int'. This function ensure that they agree.
9673 TARGS, PARMS are the same as the arguments of unify.
9674 ARGS contains template arguments from all levels. */
9677 verify_class_unification (tree targs, tree parms, tree args)
9679 parms = tsubst (parms, add_outermost_template_args (args, targs),
9680 tf_none, NULL_TREE);
9681 if (parms == error_mark_node)
9684 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9687 /* PARM is a template class (perhaps with unbound template
9688 parameters). ARG is a fully instantiated type. If ARG can be
9689 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9690 TARGS are as for unify. */
9693 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9697 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9698 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9699 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9702 /* We need to make a new template argument vector for the call to
9703 unify. If we used TARGS, we'd clutter it up with the result of
9704 the attempted unification, even if this class didn't work out.
9705 We also don't want to commit ourselves to all the unifications
9706 we've already done, since unification is supposed to be done on
9707 an argument-by-argument basis. In other words, consider the
9708 following pathological case:
9710 template <int I, int J, int K>
9713 template <int I, int J>
9714 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9716 template <int I, int J, int K>
9717 void f(S<I, J, K>, S<I, I, I>);
9726 Now, by the time we consider the unification involving `s2', we
9727 already know that we must have `f<0, 0, 0>'. But, even though
9728 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9729 because there are two ways to unify base classes of S<0, 1, 2>
9730 with S<I, I, I>. If we kept the already deduced knowledge, we
9731 would reject the possibility I=1. */
9732 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9734 /* If unification failed, we're done. */
9735 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9736 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9742 /* Given a template type PARM and a class type ARG, find the unique
9743 base type in ARG that is an instance of PARM. We do not examine
9744 ARG itself; only its base-classes. If there is not exactly one
9745 appropriate base class, return NULL_TREE. PARM may be the type of
9746 a partial specialization, as well as a plain template type. Used
9750 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9752 tree rval = NULL_TREE;
9755 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9757 binfo = TYPE_BINFO (complete_type (arg));
9759 /* The type could not be completed. */
9762 /* Walk in inheritance graph order. The search order is not
9763 important, and this avoids multiple walks of virtual bases. */
9764 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9766 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9770 /* If there is more than one satisfactory baseclass, then:
9774 If they yield more than one possible deduced A, the type
9778 if (rval && !same_type_p (r, rval))
9788 /* Returns the level of DECL, which declares a template parameter. */
9791 template_decl_level (tree decl)
9793 switch (TREE_CODE (decl))
9797 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9800 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9808 /* Decide whether ARG can be unified with PARM, considering only the
9809 cv-qualifiers of each type, given STRICT as documented for unify.
9810 Returns nonzero iff the unification is OK on that basis. */
9813 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9815 int arg_quals = cp_type_quals (arg);
9816 int parm_quals = cp_type_quals (parm);
9818 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9819 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9821 /* Although a CVR qualifier is ignored when being applied to a
9822 substituted template parameter ([8.3.2]/1 for example), that
9823 does not apply during deduction [14.8.2.4]/1, (even though
9824 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9825 this). Except when we're allowing additional CV qualifiers
9826 at the outer level [14.8.2.1]/3,1st bullet. */
9827 if ((TREE_CODE (arg) == REFERENCE_TYPE
9828 || TREE_CODE (arg) == FUNCTION_TYPE
9829 || TREE_CODE (arg) == METHOD_TYPE)
9830 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9833 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9834 && (parm_quals & TYPE_QUAL_RESTRICT))
9838 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9839 && (arg_quals & parm_quals) != parm_quals)
9842 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9843 && (parm_quals & arg_quals) != arg_quals)
9849 /* Takes parameters as for type_unification. Returns 0 if the
9850 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9851 bitwise or of the following flags:
9854 Require an exact match between PARM and ARG.
9855 UNIFY_ALLOW_MORE_CV_QUAL:
9856 Allow the deduced ARG to be more cv-qualified (by qualification
9857 conversion) than ARG.
9858 UNIFY_ALLOW_LESS_CV_QUAL:
9859 Allow the deduced ARG to be less cv-qualified than ARG.
9860 UNIFY_ALLOW_DERIVED:
9861 Allow the deduced ARG to be a template base class of ARG,
9862 or a pointer to a template base class of the type pointed to by
9864 UNIFY_ALLOW_INTEGER:
9865 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9866 case for more information.
9867 UNIFY_ALLOW_OUTER_LEVEL:
9868 This is the outermost level of a deduction. Used to determine validity
9869 of qualification conversions. A valid qualification conversion must
9870 have const qualified pointers leading up to the inner type which
9871 requires additional CV quals, except at the outer level, where const
9872 is not required [conv.qual]. It would be normal to set this flag in
9873 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9874 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9875 This is the outermost level of a deduction, and PARM can be more CV
9876 qualified at this point.
9877 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9878 This is the outermost level of a deduction, and PARM can be less CV
9879 qualified at this point. */
9882 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9887 int strict_in = strict;
9889 /* I don't think this will do the right thing with respect to types.
9890 But the only case I've seen it in so far has been array bounds, where
9891 signedness is the only information lost, and I think that will be
9893 while (TREE_CODE (parm) == NOP_EXPR)
9894 parm = TREE_OPERAND (parm, 0);
9896 if (arg == error_mark_node)
9898 if (arg == unknown_type_node)
9899 /* We can't deduce anything from this, but we might get all the
9900 template args from other function args. */
9903 /* If PARM uses template parameters, then we can't bail out here,
9904 even if ARG == PARM, since we won't record unifications for the
9905 template parameters. We might need them if we're trying to
9906 figure out which of two things is more specialized. */
9907 if (arg == parm && !uses_template_parms (parm))
9910 /* Immediately reject some pairs that won't unify because of
9911 cv-qualification mismatches. */
9912 if (TREE_CODE (arg) == TREE_CODE (parm)
9914 /* It is the elements of the array which hold the cv quals of an array
9915 type, and the elements might be template type parms. We'll check
9917 && TREE_CODE (arg) != ARRAY_TYPE
9918 /* We check the cv-qualifiers when unifying with template type
9919 parameters below. We want to allow ARG `const T' to unify with
9920 PARM `T' for example, when computing which of two templates
9921 is more specialized, for example. */
9922 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9923 && !check_cv_quals_for_unify (strict_in, arg, parm))
9926 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9927 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9928 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9929 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9930 strict &= ~UNIFY_ALLOW_DERIVED;
9931 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9932 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9934 switch (TREE_CODE (parm))
9938 case UNBOUND_CLASS_TEMPLATE:
9939 /* In a type which contains a nested-name-specifier, template
9940 argument values cannot be deduced for template parameters used
9941 within the nested-name-specifier. */
9944 case TEMPLATE_TYPE_PARM:
9945 case TEMPLATE_TEMPLATE_PARM:
9946 case BOUND_TEMPLATE_TEMPLATE_PARM:
9947 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9949 if (TEMPLATE_TYPE_LEVEL (parm)
9950 != template_decl_level (tparm))
9951 /* The PARM is not one we're trying to unify. Just check
9952 to see if it matches ARG. */
9953 return (TREE_CODE (arg) == TREE_CODE (parm)
9954 && same_type_p (parm, arg)) ? 0 : 1;
9955 idx = TEMPLATE_TYPE_IDX (parm);
9956 targ = TREE_VEC_ELT (targs, idx);
9957 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9959 /* Check for mixed types and values. */
9960 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9961 && TREE_CODE (tparm) != TYPE_DECL)
9962 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9963 && TREE_CODE (tparm) != TEMPLATE_DECL))
9966 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9968 /* ARG must be constructed from a template class or a template
9969 template parameter. */
9970 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9971 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9975 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9976 tree parmvec = TYPE_TI_ARGS (parm);
9977 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9979 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9982 /* The parameter and argument roles have to be switched here
9983 in order to handle default arguments properly. For example,
9984 template<template <class> class TT> void f(TT<int>)
9985 should be able to accept vector<int> which comes from
9986 template <class T, class Allocator = allocator>
9989 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9993 /* Deduce arguments T, i from TT<T> or TT<i>.
9994 We check each element of PARMVEC and ARGVEC individually
9995 rather than the whole TREE_VEC since they can have
9996 different number of elements. */
9998 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
10000 if (unify (tparms, targs,
10001 TREE_VEC_ELT (parmvec, i),
10002 TREE_VEC_ELT (argvec, i),
10007 arg = TYPE_TI_TEMPLATE (arg);
10009 /* Fall through to deduce template name. */
10012 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10013 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10015 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
10017 /* Simple cases: Value already set, does match or doesn't. */
10018 if (targ != NULL_TREE && template_args_equal (targ, arg))
10025 /* If PARM is `const T' and ARG is only `int', we don't have
10026 a match unless we are allowing additional qualification.
10027 If ARG is `const int' and PARM is just `T' that's OK;
10028 that binds `const int' to `T'. */
10029 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10033 /* Consider the case where ARG is `const volatile int' and
10034 PARM is `const T'. Then, T should be `volatile int'. */
10035 arg = cp_build_qualified_type_real
10036 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10037 if (arg == error_mark_node)
10040 /* Simple cases: Value already set, does match or doesn't. */
10041 if (targ != NULL_TREE && same_type_p (targ, arg))
10046 /* Make sure that ARG is not a variable-sized array. (Note
10047 that were talking about variable-sized arrays (like
10048 `int[n]'), rather than arrays of unknown size (like
10049 `int[]').) We'll get very confused by such a type since
10050 the bound of the array will not be computable in an
10051 instantiation. Besides, such types are not allowed in
10052 ISO C++, so we can do as we please here. */
10053 if (variably_modified_type_p (arg, NULL_TREE))
10057 TREE_VEC_ELT (targs, idx) = arg;
10060 case TEMPLATE_PARM_INDEX:
10061 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10063 if (TEMPLATE_PARM_LEVEL (parm)
10064 != template_decl_level (tparm))
10065 /* The PARM is not one we're trying to unify. Just check
10066 to see if it matches ARG. */
10067 return !(TREE_CODE (arg) == TREE_CODE (parm)
10068 && cp_tree_equal (parm, arg));
10070 idx = TEMPLATE_PARM_IDX (parm);
10071 targ = TREE_VEC_ELT (targs, idx);
10074 return !cp_tree_equal (targ, arg);
10076 /* [temp.deduct.type] If, in the declaration of a function template
10077 with a non-type template-parameter, the non-type
10078 template-parameter is used in an expression in the function
10079 parameter-list and, if the corresponding template-argument is
10080 deduced, the template-argument type shall match the type of the
10081 template-parameter exactly, except that a template-argument
10082 deduced from an array bound may be of any integral type.
10083 The non-type parameter might use already deduced type parameters. */
10084 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10085 if (!TREE_TYPE (arg))
10086 /* Template-parameter dependent expression. Just accept it for now.
10087 It will later be processed in convert_template_argument. */
10089 else if (same_type_p (TREE_TYPE (arg), tparm))
10091 else if ((strict & UNIFY_ALLOW_INTEGER)
10092 && (TREE_CODE (tparm) == INTEGER_TYPE
10093 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10094 /* Convert the ARG to the type of PARM; the deduced non-type
10095 template argument must exactly match the types of the
10096 corresponding parameter. */
10097 arg = fold (build_nop (TREE_TYPE (parm), arg));
10098 else if (uses_template_parms (tparm))
10099 /* We haven't deduced the type of this parameter yet. Try again
10105 TREE_VEC_ELT (targs, idx) = arg;
10110 /* A pointer-to-member constant can be unified only with
10111 another constant. */
10112 if (TREE_CODE (arg) != PTRMEM_CST)
10115 /* Just unify the class member. It would be useless (and possibly
10116 wrong, depending on the strict flags) to unify also
10117 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10118 arg refer to the same variable, even if through different
10119 classes. For instance:
10121 struct A { int x; };
10124 Unification of &A::x and &B::x must succeed. */
10125 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10126 PTRMEM_CST_MEMBER (arg), strict);
10131 if (TREE_CODE (arg) != POINTER_TYPE)
10134 /* [temp.deduct.call]
10136 A can be another pointer or pointer to member type that can
10137 be converted to the deduced A via a qualification
10138 conversion (_conv.qual_).
10140 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10141 This will allow for additional cv-qualification of the
10142 pointed-to types if appropriate. */
10144 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10145 /* The derived-to-base conversion only persists through one
10146 level of pointers. */
10147 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10149 return unify (tparms, targs, TREE_TYPE (parm),
10150 TREE_TYPE (arg), strict);
10153 case REFERENCE_TYPE:
10154 if (TREE_CODE (arg) != REFERENCE_TYPE)
10156 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10157 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10160 if (TREE_CODE (arg) != ARRAY_TYPE)
10162 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10163 != (TYPE_DOMAIN (arg) == NULL_TREE))
10165 if (TYPE_DOMAIN (parm) != NULL_TREE)
10170 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10171 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10173 /* Our representation of array types uses "N - 1" as the
10174 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10175 not an integer constant. */
10176 if (TREE_CODE (parm_max) == MINUS_EXPR)
10178 arg_max = fold (build2 (PLUS_EXPR,
10181 TREE_OPERAND (parm_max, 1)));
10182 parm_max = TREE_OPERAND (parm_max, 0);
10185 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10188 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10189 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10196 case ENUMERAL_TYPE:
10198 if (TREE_CODE (arg) != TREE_CODE (parm))
10201 /* We have already checked cv-qualification at the top of the
10203 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10206 /* As far as unification is concerned, this wins. Later checks
10207 will invalidate it if necessary. */
10210 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10211 /* Type INTEGER_CST can come from ordinary constant template args. */
10213 while (TREE_CODE (arg) == NOP_EXPR)
10214 arg = TREE_OPERAND (arg, 0);
10216 if (TREE_CODE (arg) != INTEGER_CST)
10218 return !tree_int_cst_equal (parm, arg);
10223 if (TREE_CODE (arg) != TREE_VEC)
10225 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10227 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10228 if (unify (tparms, targs,
10229 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10237 if (TREE_CODE (arg) != TREE_CODE (parm))
10240 if (TYPE_PTRMEMFUNC_P (parm))
10242 if (!TYPE_PTRMEMFUNC_P (arg))
10245 return unify (tparms, targs,
10246 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10247 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10251 if (CLASSTYPE_TEMPLATE_INFO (parm))
10253 tree t = NULL_TREE;
10255 if (strict_in & UNIFY_ALLOW_DERIVED)
10257 /* First, we try to unify the PARM and ARG directly. */
10258 t = try_class_unification (tparms, targs,
10263 /* Fallback to the special case allowed in
10264 [temp.deduct.call]:
10266 If P is a class, and P has the form
10267 template-id, then A can be a derived class of
10268 the deduced A. Likewise, if P is a pointer to
10269 a class of the form template-id, A can be a
10270 pointer to a derived class pointed to by the
10272 t = get_template_base (tparms, targs, parm, arg);
10278 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10279 && (CLASSTYPE_TI_TEMPLATE (parm)
10280 == CLASSTYPE_TI_TEMPLATE (arg)))
10281 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10282 Then, we should unify `int' and `U'. */
10285 /* There's no chance of unification succeeding. */
10288 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10289 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10291 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10296 case FUNCTION_TYPE:
10297 if (TREE_CODE (arg) != TREE_CODE (parm))
10300 if (unify (tparms, targs, TREE_TYPE (parm),
10301 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10303 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10304 TYPE_ARG_TYPES (arg), 1,
10305 DEDUCE_EXACT, 0, -1);
10308 if (TREE_CODE (arg) != OFFSET_TYPE)
10310 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10311 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10313 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10317 if (DECL_TEMPLATE_PARM_P (parm))
10318 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10319 if (arg != decl_constant_value (parm))
10324 case TEMPLATE_DECL:
10325 /* Matched cases are handled by the ARG == PARM test above. */
10329 gcc_assert (EXPR_P (parm));
10331 /* We must be looking at an expression. This can happen with
10335 void foo(S<I>, S<I + 2>);
10337 This is a "nondeduced context":
10341 The nondeduced contexts are:
10343 --A type that is a template-id in which one or more of
10344 the template-arguments is an expression that references
10345 a template-parameter.
10347 In these cases, we assume deduction succeeded, but don't
10348 actually infer any unifications. */
10350 if (!uses_template_parms (parm)
10351 && !template_args_equal (parm, arg))
10358 /* Note that DECL can be defined in this translation unit, if
10362 mark_definable (tree decl)
10365 DECL_NOT_REALLY_EXTERN (decl) = 1;
10366 FOR_EACH_CLONE (clone, decl)
10367 DECL_NOT_REALLY_EXTERN (clone) = 1;
10370 /* Called if RESULT is explicitly instantiated, or is a member of an
10371 explicitly instantiated class. */
10374 mark_decl_instantiated (tree result, int extern_p)
10376 SET_DECL_EXPLICIT_INSTANTIATION (result);
10378 /* If this entity has already been written out, it's too late to
10379 make any modifications. */
10380 if (TREE_ASM_WRITTEN (result))
10383 if (TREE_CODE (result) != FUNCTION_DECL)
10384 /* The TREE_PUBLIC flag for function declarations will have been
10385 set correctly by tsubst. */
10386 TREE_PUBLIC (result) = 1;
10388 /* This might have been set by an earlier implicit instantiation. */
10389 DECL_COMDAT (result) = 0;
10392 DECL_NOT_REALLY_EXTERN (result) = 0;
10395 mark_definable (result);
10396 /* Always make artificials weak. */
10397 if (DECL_ARTIFICIAL (result) && flag_weak)
10398 comdat_linkage (result);
10399 /* For WIN32 we also want to put explicit instantiations in
10400 linkonce sections. */
10401 else if (TREE_PUBLIC (result))
10402 maybe_make_one_only (result);
10405 /* If EXTERN_P, then this function will not be emitted -- unless
10406 followed by an explicit instantiation, at which point its linkage
10407 will be adjusted. If !EXTERN_P, then this function will be
10408 emitted here. In neither circumstance do we want
10409 import_export_decl to adjust the linkage. */
10410 DECL_INTERFACE_KNOWN (result) = 1;
10413 /* Given two function templates PAT1 and PAT2, return:
10415 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
10417 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10418 -1 if PAT2 is more specialized than PAT1.
10419 0 if neither is more specialized.
10421 LEN is passed through to fn_type_unification. */
10424 more_specialized (tree pat1, tree pat2, int deduce, int len)
10429 /* If template argument deduction succeeds, we substitute the
10430 resulting arguments into non-deduced contexts. While doing that,
10431 we must be aware that we may encounter dependent types. */
10432 ++processing_template_decl;
10433 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
10434 NULL_TREE, 0, deduce, len);
10438 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
10439 NULL_TREE, 0, deduce, len);
10442 --processing_template_decl;
10447 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10449 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10450 -1 if PAT2 is more specialized than PAT1.
10451 0 if neither is more specialized.
10453 FULL_ARGS is the full set of template arguments that triggers this
10454 partial ordering. */
10457 more_specialized_class (tree pat1, tree pat2, tree full_args)
10462 /* Just like what happens for functions, if we are ordering between
10463 different class template specializations, we may encounter dependent
10464 types in the arguments, and we need our dependency check functions
10465 to behave correctly. */
10466 ++processing_template_decl;
10467 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10468 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10472 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10473 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10476 --processing_template_decl;
10481 /* Return the template arguments that will produce the function signature
10482 DECL from the function template FN, with the explicit template
10483 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
10484 also match. Return NULL_TREE if no satisfactory arguments could be
10485 found. DEDUCE and LEN are passed through to fn_type_unification. */
10488 get_bindings_real (tree fn,
10490 tree explicit_args,
10495 int ntparms = DECL_NTPARMS (fn);
10496 tree targs = make_tree_vec (ntparms);
10498 tree decl_arg_types;
10501 /* Substitute the explicit template arguments into the type of DECL.
10502 The call to fn_type_unification will handle substitution into the
10504 decl_type = TREE_TYPE (decl);
10505 if (explicit_args && uses_template_parms (decl_type))
10508 tree converted_args;
10510 if (DECL_TEMPLATE_INFO (decl))
10511 tmpl = DECL_TI_TEMPLATE (decl);
10513 /* We can get here for some invalid specializations. */
10517 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10518 explicit_args, NULL_TREE,
10519 tf_none, /*require_all_arguments=*/0));
10520 if (converted_args == error_mark_node)
10523 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10524 if (decl_type == error_mark_node)
10528 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10529 /* Never do unification on the 'this' parameter. */
10530 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10531 decl_arg_types = TREE_CHAIN (decl_arg_types);
10533 i = fn_type_unification (fn, explicit_args, targs,
10535 (check_rettype || DECL_CONV_FN_P (fn)
10536 ? TREE_TYPE (decl_type) : NULL_TREE),
10545 /* For most uses, we want to check the return type. */
10548 get_bindings (tree fn, tree decl, tree explicit_args)
10550 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10553 /* But for resolve_overloaded_unification, we only care about the parameter
10557 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10559 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10562 /* Return the innermost template arguments that, when applied to a
10563 template specialization whose innermost template parameters are
10564 TPARMS, and whose specialization arguments are PARMS, yield the
10567 For example, suppose we have:
10569 template <class T, class U> struct S {};
10570 template <class T> struct S<T*, int> {};
10572 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10573 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10574 int}. The resulting vector will be {double}, indicating that `T'
10575 is bound to `double'. */
10578 get_class_bindings (tree tparms, tree parms, tree args)
10580 int i, ntparms = TREE_VEC_LENGTH (tparms);
10581 tree vec = make_tree_vec (ntparms);
10583 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10587 for (i = 0; i < ntparms; ++i)
10588 if (! TREE_VEC_ELT (vec, i))
10591 if (verify_class_unification (vec, parms, args))
10597 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10598 Pick the most specialized template, and return the corresponding
10599 instantiation, or if there is no corresponding instantiation, the
10600 template itself. If there is no most specialized template,
10601 error_mark_node is returned. If there are no templates at all,
10602 NULL_TREE is returned. */
10605 most_specialized_instantiation (tree instantiations)
10610 if (!instantiations)
10613 champ = instantiations;
10614 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10616 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10624 fn = TREE_CHAIN (fn);
10626 return error_mark_node;
10632 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10634 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10637 return error_mark_node;
10640 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10643 /* Return the most specialized of the list of templates in FNS that can
10644 produce an instantiation matching DECL, given the explicit template
10645 arguments EXPLICIT_ARGS. */
10648 most_specialized (tree fns, tree decl, tree explicit_args)
10650 tree candidates = NULL_TREE;
10653 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10655 tree candidate = TREE_VALUE (fn);
10657 args = get_bindings (candidate, decl, explicit_args);
10659 candidates = tree_cons (NULL_TREE, candidate, candidates);
10662 return most_specialized_instantiation (candidates);
10665 /* If DECL is a specialization of some template, return the most
10666 general such template. Otherwise, returns NULL_TREE.
10668 For example, given:
10670 template <class T> struct S { template <class U> void f(U); };
10672 if TMPL is `template <class U> void S<int>::f(U)' this will return
10673 the full template. This function will not trace past partial
10674 specializations, however. For example, given in addition:
10676 template <class T> struct S<T*> { template <class U> void f(U); };
10678 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10679 `template <class T> template <class U> S<T*>::f(U)'. */
10682 most_general_template (tree decl)
10684 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10685 an immediate specialization. */
10686 if (TREE_CODE (decl) == FUNCTION_DECL)
10688 if (DECL_TEMPLATE_INFO (decl)) {
10689 decl = DECL_TI_TEMPLATE (decl);
10691 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10692 template friend. */
10693 if (TREE_CODE (decl) != TEMPLATE_DECL)
10699 /* Look for more and more general templates. */
10700 while (DECL_TEMPLATE_INFO (decl))
10702 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10703 (See cp-tree.h for details.) */
10704 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10707 if (CLASS_TYPE_P (TREE_TYPE (decl))
10708 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10711 /* Stop if we run into an explicitly specialized class template. */
10712 if (!DECL_NAMESPACE_SCOPE_P (decl)
10713 && DECL_CONTEXT (decl)
10714 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10717 decl = DECL_TI_TEMPLATE (decl);
10723 /* Return the most specialized of the class template specializations
10724 of TMPL which can produce an instantiation matching ARGS, or
10725 error_mark_node if the choice is ambiguous. */
10728 most_specialized_class (tree tmpl, tree args)
10730 tree list = NULL_TREE;
10735 tmpl = most_general_template (tmpl);
10736 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10739 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10742 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10743 TREE_TYPE (list) = TREE_TYPE (t);
10752 t = TREE_CHAIN (t);
10753 for (; t; t = TREE_CHAIN (t))
10755 fate = more_specialized_class (champ, t, args);
10762 t = TREE_CHAIN (t);
10764 return error_mark_node;
10770 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10772 fate = more_specialized_class (champ, t, args);
10774 return error_mark_node;
10780 /* Explicitly instantiate DECL. */
10783 do_decl_instantiation (tree decl, tree storage)
10785 tree result = NULL_TREE;
10789 /* An error occurred, for which grokdeclarator has already issued
10790 an appropriate message. */
10792 else if (! DECL_LANG_SPECIFIC (decl))
10794 error ("explicit instantiation of non-template %q#D", decl);
10797 else if (TREE_CODE (decl) == VAR_DECL)
10799 /* There is an asymmetry here in the way VAR_DECLs and
10800 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10801 the latter, the DECL we get back will be marked as a
10802 template instantiation, and the appropriate
10803 DECL_TEMPLATE_INFO will be set up. This does not happen for
10804 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10805 should handle VAR_DECLs as it currently handles
10807 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10808 if (!result || TREE_CODE (result) != VAR_DECL)
10810 error ("no matching template for %qD found", decl);
10814 else if (TREE_CODE (decl) != FUNCTION_DECL)
10816 error ("explicit instantiation of %q#D", decl);
10822 /* Check for various error cases. Note that if the explicit
10823 instantiation is valid the RESULT will currently be marked as an
10824 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10825 until we get here. */
10827 if (DECL_TEMPLATE_SPECIALIZATION (result))
10829 /* DR 259 [temp.spec].
10831 Both an explicit instantiation and a declaration of an explicit
10832 specialization shall not appear in a program unless the explicit
10833 instantiation follows a declaration of the explicit specialization.
10835 For a given set of template parameters, if an explicit
10836 instantiation of a template appears after a declaration of an
10837 explicit specialization for that template, the explicit
10838 instantiation has no effect. */
10841 else if (DECL_EXPLICIT_INSTANTIATION (result))
10845 No program shall explicitly instantiate any template more
10848 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10849 the first instantiation was `extern' and the second is not,
10850 and EXTERN_P for the opposite case. */
10851 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10852 pedwarn ("duplicate explicit instantiation of %q#D", result);
10853 /* If an "extern" explicit instantiation follows an ordinary
10854 explicit instantiation, the template is instantiated. */
10858 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10860 error ("no matching template for %qD found", result);
10863 else if (!DECL_TEMPLATE_INFO (result))
10865 pedwarn ("explicit instantiation of non-template %q#D", result);
10869 if (storage == NULL_TREE)
10871 else if (storage == ridpointers[(int) RID_EXTERN])
10873 if (pedantic && !in_system_header)
10874 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
10879 error ("storage class %qD applied to template instantiation", storage);
10881 mark_decl_instantiated (result, extern_p);
10883 instantiate_decl (result, /*defer_ok=*/1, /*undefined_ok=*/0);
10887 mark_class_instantiated (tree t, int extern_p)
10889 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10890 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10891 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10892 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10895 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10896 rest_of_type_compilation (t, 1);
10900 /* Called from do_type_instantiation through binding_table_foreach to
10901 do recursive instantiation for the type bound in ENTRY. */
10903 bt_instantiate_type_proc (binding_entry entry, void *data)
10905 tree storage = *(tree *) data;
10907 if (IS_AGGR_TYPE (entry->type)
10908 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10909 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10912 /* Called from do_type_instantiation to instantiate a member
10913 (a member function or a static member variable) of an
10914 explicitly instantiated class template. */
10916 instantiate_class_member (tree decl, int extern_p)
10918 mark_decl_instantiated (decl, extern_p);
10920 instantiate_decl (decl, /*defer_ok=*/1, /* undefined_ok=*/1);
10923 /* Perform an explicit instantiation of template class T. STORAGE, if
10924 non-null, is the RID for extern, inline or static. COMPLAIN is
10925 nonzero if this is called from the parser, zero if called recursively,
10926 since the standard is unclear (as detailed below). */
10929 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10934 int previous_instantiation_extern_p = 0;
10936 if (TREE_CODE (t) == TYPE_DECL)
10939 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10941 error ("explicit instantiation of non-template type %qT", t);
10947 if (!COMPLETE_TYPE_P (t))
10949 if (complain & tf_error)
10950 error ("explicit instantiation of %q#T before definition of template",
10955 if (storage != NULL_TREE)
10957 if (pedantic && !in_system_header)
10958 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
10961 if (storage == ridpointers[(int) RID_INLINE])
10963 else if (storage == ridpointers[(int) RID_EXTERN])
10965 else if (storage == ridpointers[(int) RID_STATIC])
10969 error ("storage class %qD applied to template instantiation",
10975 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10977 /* DR 259 [temp.spec].
10979 Both an explicit instantiation and a declaration of an explicit
10980 specialization shall not appear in a program unless the explicit
10981 instantiation follows a declaration of the explicit specialization.
10983 For a given set of template parameters, if an explicit
10984 instantiation of a template appears after a declaration of an
10985 explicit specialization for that template, the explicit
10986 instantiation has no effect. */
10989 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10993 No program shall explicitly instantiate any template more
10996 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
10997 instantiation was `extern'. If EXTERN_P then the second is.
10998 These cases are OK. */
10999 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11001 if (!previous_instantiation_extern_p && !extern_p
11002 && (complain & tf_error))
11003 pedwarn ("duplicate explicit instantiation of %q#T", t);
11005 /* If we've already instantiated the template, just return now. */
11006 if (!CLASSTYPE_INTERFACE_ONLY (t))
11010 mark_class_instantiated (t, extern_p);
11018 /* In contrast to implicit instantiation, where only the
11019 declarations, and not the definitions, of members are
11020 instantiated, we have here:
11024 The explicit instantiation of a class template specialization
11025 implies the instantiation of all of its members not
11026 previously explicitly specialized in the translation unit
11027 containing the explicit instantiation.
11029 Of course, we can't instantiate member template classes, since
11030 we don't have any arguments for them. Note that the standard
11031 is unclear on whether the instantiation of the members are
11032 *explicit* instantiations or not. However, the most natural
11033 interpretation is that it should be an explicit instantiation. */
11036 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11037 if (TREE_CODE (tmp) == FUNCTION_DECL
11038 && DECL_TEMPLATE_INSTANTIATION (tmp))
11039 instantiate_class_member (tmp, extern_p);
11041 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11042 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11043 instantiate_class_member (tmp, extern_p);
11045 if (CLASSTYPE_NESTED_UTDS (t))
11046 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11047 bt_instantiate_type_proc, &storage);
11051 /* Given a function DECL, which is a specialization of TMPL, modify
11052 DECL to be a re-instantiation of TMPL with the same template
11053 arguments. TMPL should be the template into which tsubst'ing
11054 should occur for DECL, not the most general template.
11056 One reason for doing this is a scenario like this:
11059 void f(const T&, int i);
11061 void g() { f(3, 7); }
11064 void f(const T& t, const int i) { }
11066 Note that when the template is first instantiated, with
11067 instantiate_template, the resulting DECL will have no name for the
11068 first parameter, and the wrong type for the second. So, when we go
11069 to instantiate the DECL, we regenerate it. */
11072 regenerate_decl_from_template (tree decl, tree tmpl)
11074 /* The arguments used to instantiate DECL, from the most general
11079 args = DECL_TI_ARGS (decl);
11080 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11082 /* Make sure that we can see identifiers, and compute access
11084 push_access_scope (decl);
11086 if (TREE_CODE (decl) == FUNCTION_DECL)
11094 args_depth = TMPL_ARGS_DEPTH (args);
11095 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11096 if (args_depth > parms_depth)
11097 args = get_innermost_template_args (args, parms_depth);
11099 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11100 args, tf_error, NULL_TREE);
11102 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11105 /* Merge parameter declarations. */
11106 decl_parm = skip_artificial_parms_for (decl,
11107 DECL_ARGUMENTS (decl));
11109 = skip_artificial_parms_for (code_pattern,
11110 DECL_ARGUMENTS (code_pattern));
11115 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11116 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11117 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11119 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11120 TREE_TYPE (decl_parm) = parm_type;
11121 decl_parm = TREE_CHAIN (decl_parm);
11122 pattern_parm = TREE_CHAIN (pattern_parm);
11125 /* Merge additional specifiers from the CODE_PATTERN. */
11126 if (DECL_DECLARED_INLINE_P (code_pattern)
11127 && !DECL_DECLARED_INLINE_P (decl))
11128 DECL_DECLARED_INLINE_P (decl) = 1;
11129 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11130 DECL_INLINE (decl) = 1;
11132 else if (TREE_CODE (decl) == VAR_DECL)
11134 if (!DECL_INITIALIZED_IN_CLASS_P (decl)
11135 && DECL_INITIAL (code_pattern))
11136 DECL_INITIAL (decl) =
11137 tsubst_expr (DECL_INITIAL (code_pattern), args,
11138 tf_error, DECL_TI_TEMPLATE (decl));
11141 gcc_unreachable ();
11143 pop_access_scope (decl);
11146 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11147 substituted to get DECL. */
11150 template_for_substitution (tree decl)
11152 tree tmpl = DECL_TI_TEMPLATE (decl);
11154 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11155 for the instantiation. This is not always the most general
11156 template. Consider, for example:
11159 struct S { template <class U> void f();
11160 template <> void f<int>(); };
11162 and an instantiation of S<double>::f<int>. We want TD to be the
11163 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11164 while (/* An instantiation cannot have a definition, so we need a
11165 more general template. */
11166 DECL_TEMPLATE_INSTANTIATION (tmpl)
11167 /* We must also deal with friend templates. Given:
11169 template <class T> struct S {
11170 template <class U> friend void f() {};
11173 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11174 so far as the language is concerned, but that's still
11175 where we get the pattern for the instantiation from. On
11176 other hand, if the definition comes outside the class, say:
11178 template <class T> struct S {
11179 template <class U> friend void f();
11181 template <class U> friend void f() {}
11183 we don't need to look any further. That's what the check for
11184 DECL_INITIAL is for. */
11185 || (TREE_CODE (decl) == FUNCTION_DECL
11186 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11187 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11189 /* The present template, TD, should not be a definition. If it
11190 were a definition, we should be using it! Note that we
11191 cannot restructure the loop to just keep going until we find
11192 a template with a definition, since that might go too far if
11193 a specialization was declared, but not defined. */
11194 gcc_assert (TREE_CODE (decl) != VAR_DECL
11195 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11197 /* Fetch the more general template. */
11198 tmpl = DECL_TI_TEMPLATE (tmpl);
11204 /* Produce the definition of D, a _DECL generated from a template. If
11205 DEFER_OK is nonzero, then we don't have to actually do the
11206 instantiation now; we just have to do it sometime. Normally it is
11207 an error if this is an explicit instantiation but D is undefined.
11208 If UNDEFINED_OK is nonzero, then instead we treat it as an implicit
11209 instantiation. UNDEFINED_OK is nonzero only if we are being used
11210 to instantiate the members of an explicitly instantiated class
11215 instantiate_decl (tree d, int defer_ok, int undefined_ok)
11217 tree tmpl = DECL_TI_TEMPLATE (d);
11224 int pattern_defined;
11226 location_t saved_loc = input_location;
11228 /* This function should only be used to instantiate templates for
11229 functions and static member variables. */
11230 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11231 || TREE_CODE (d) == VAR_DECL);
11233 /* Variables are never deferred; if instantiation is required, they
11234 are instantiated right away. That allows for better code in the
11235 case that an expression refers to the value of the variable --
11236 if the variable has a constant value the referring expression can
11237 take advantage of that fact. */
11238 if (TREE_CODE (d) == VAR_DECL)
11241 /* Don't instantiate cloned functions. Instead, instantiate the
11242 functions they cloned. */
11243 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11244 d = DECL_CLONED_FUNCTION (d);
11246 if (DECL_TEMPLATE_INSTANTIATED (d))
11247 /* D has already been instantiated. It might seem reasonable to
11248 check whether or not D is an explicit instantiation, and, if so,
11249 stop here. But when an explicit instantiation is deferred
11250 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11251 is set, even though we still need to do the instantiation. */
11254 /* If we already have a specialization of this declaration, then
11255 there's no reason to instantiate it. Note that
11256 retrieve_specialization gives us both instantiations and
11257 specializations, so we must explicitly check
11258 DECL_TEMPLATE_SPECIALIZATION. */
11259 gen_tmpl = most_general_template (tmpl);
11260 gen_args = DECL_TI_ARGS (d);
11261 spec = retrieve_specialization (gen_tmpl, gen_args,
11262 /*class_specializations_p=*/false);
11263 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11266 /* This needs to happen before any tsubsting. */
11267 if (! push_tinst_level (d))
11270 timevar_push (TV_PARSE);
11272 /* We may be in the middle of deferred access check. Disable it now. */
11273 push_deferring_access_checks (dk_no_deferred);
11275 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11276 for the instantiation. */
11277 td = template_for_substitution (d);
11278 code_pattern = DECL_TEMPLATE_RESULT (td);
11280 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11281 || DECL_TEMPLATE_SPECIALIZATION (td))
11282 /* In the case of a friend template whose definition is provided
11283 outside the class, we may have too many arguments. Drop the
11284 ones we don't need. The same is true for specializations. */
11285 args = get_innermost_template_args
11286 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11290 if (TREE_CODE (d) == FUNCTION_DECL)
11291 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11293 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11294 /* Unless an explicit instantiation directive has already determined
11295 the linkage of D, remember that a definition is available for
11297 if (pattern_defined
11298 && !DECL_INTERFACE_KNOWN (d)
11299 && !DECL_NOT_REALLY_EXTERN (d))
11300 mark_definable (d);
11302 input_location = DECL_SOURCE_LOCATION (d);
11304 if (! pattern_defined && DECL_EXPLICIT_INSTANTIATION (d) && undefined_ok)
11306 DECL_NOT_REALLY_EXTERN (d) = 0;
11307 SET_DECL_IMPLICIT_INSTANTIATION (d);
11312 /* Recheck the substitutions to obtain any warning messages
11313 about ignoring cv qualifiers. */
11314 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11315 tree type = TREE_TYPE (gen);
11317 /* Make sure that we can see identifiers, and compute access
11318 correctly. D is already the target FUNCTION_DECL with the
11320 push_access_scope (d);
11322 if (TREE_CODE (gen) == FUNCTION_DECL)
11324 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11325 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11326 tf_error | tf_warning, d);
11327 /* Don't simply tsubst the function type, as that will give
11328 duplicate warnings about poor parameter qualifications.
11329 The function arguments are the same as the decl_arguments
11330 without the top level cv qualifiers. */
11331 type = TREE_TYPE (type);
11333 tsubst (type, gen_args, tf_error | tf_warning, d);
11335 pop_access_scope (d);
11338 /* We should have set up DECL_INITIAL in instantiate_class_template
11339 for in-class definitions of static data members. */
11340 gcc_assert (!(TREE_CODE (d) == VAR_DECL
11341 && DECL_INITIALIZED_IN_CLASS_P (d)
11342 && DECL_INITIAL (d) == NULL_TREE));
11344 /* Do not instantiate templates that we know will be defined
11346 if (DECL_INTERFACE_KNOWN (d)
11347 && DECL_REALLY_EXTERN (d)
11348 && ! (TREE_CODE (d) == FUNCTION_DECL
11349 && DECL_INLINE (d)))
11351 /* Defer all other templates, unless we have been explicitly
11352 forbidden from doing so. We restore the source position here
11353 because it's used by add_pending_template. */
11354 else if (! pattern_defined || defer_ok)
11356 input_location = saved_loc;
11358 if (at_eof && !pattern_defined
11359 && DECL_EXPLICIT_INSTANTIATION (d))
11362 The definition of a non-exported function template, a
11363 non-exported member function template, or a non-exported
11364 member function or static data member of a class template
11365 shall be present in every translation unit in which it is
11366 explicitly instantiated. */
11368 ("explicit instantiation of %qD but no definition available", d);
11370 add_pending_template (d);
11373 /* Tell the repository that D is available in this translation unit
11374 -- and see if it is supposed to be instantiated here. */
11375 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11377 /* In a PCH file, despite the fact that the repository hasn't
11378 requested instantiation in the PCH it is still possible that
11379 an instantiation will be required in a file that includes the
11382 add_pending_template (d);
11383 /* Instantiate inline functions so that the inliner can do its
11384 job, even though we'll not be emitting a copy of this
11386 if (!(TREE_CODE (d) == FUNCTION_DECL
11387 && flag_inline_trees
11388 && DECL_DECLARED_INLINE_P (d)))
11392 need_push = !cfun || !global_bindings_p ();
11394 push_to_top_level ();
11396 /* Mark D as instantiated so that recursive calls to
11397 instantiate_decl do not try to instantiate it again. */
11398 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11400 /* Regenerate the declaration in case the template has been modified
11401 by a subsequent redeclaration. */
11402 regenerate_decl_from_template (d, td);
11404 /* We already set the file and line above. Reset them now in case
11405 they changed as a result of calling regenerate_decl_from_template. */
11406 input_location = DECL_SOURCE_LOCATION (d);
11408 if (TREE_CODE (d) == VAR_DECL)
11410 /* Clear out DECL_RTL; whatever was there before may not be right
11411 since we've reset the type of the declaration. */
11412 SET_DECL_RTL (d, NULL_RTX);
11413 DECL_IN_AGGR_P (d) = 0;
11415 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11416 initializer. That function will defer actual emission until
11417 we have a chance to determine linkage. */
11418 DECL_EXTERNAL (d) = 0;
11420 /* Enter the scope of D so that access-checking works correctly. */
11421 push_nested_class (DECL_CONTEXT (d));
11423 (!DECL_INITIALIZED_IN_CLASS_P (d)
11424 ? DECL_INITIAL (d) : NULL_TREE),
11426 pop_nested_class ();
11428 else if (TREE_CODE (d) == FUNCTION_DECL)
11430 htab_t saved_local_specializations;
11435 /* Save away the current list, in case we are instantiating one
11436 template from within the body of another. */
11437 saved_local_specializations = local_specializations;
11439 /* Set up the list of local specializations. */
11440 local_specializations = htab_create (37,
11441 hash_local_specialization,
11442 eq_local_specializations,
11445 /* Set up context. */
11446 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11448 /* Create substitution entries for the parameters. */
11449 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11450 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11451 spec_parm = DECL_ARGUMENTS (d);
11452 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11454 register_local_specialization (spec_parm, tmpl_parm);
11455 spec_parm = skip_artificial_parms_for (d, spec_parm);
11456 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11460 register_local_specialization (spec_parm, tmpl_parm);
11461 tmpl_parm = TREE_CHAIN (tmpl_parm);
11462 spec_parm = TREE_CHAIN (spec_parm);
11464 gcc_assert (!spec_parm);
11466 /* Substitute into the body of the function. */
11467 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11468 tf_error | tf_warning, tmpl);
11470 /* We don't need the local specializations any more. */
11471 htab_delete (local_specializations);
11472 local_specializations = saved_local_specializations;
11474 /* Finish the function. */
11475 d = finish_function (0);
11476 expand_or_defer_fn (d);
11479 /* We're not deferring instantiation any more. */
11480 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11483 pop_from_top_level ();
11486 input_location = saved_loc;
11487 pop_deferring_access_checks ();
11488 pop_tinst_level ();
11490 timevar_pop (TV_PARSE);
11495 /* Run through the list of templates that we wish we could
11496 instantiate, and instantiate any we can. RETRIES is the
11497 number of times we retry pending template instantiation. */
11500 instantiate_pending_templates (int retries)
11503 tree last = NULL_TREE;
11505 location_t saved_loc = input_location;
11507 /* Instantiating templates may trigger vtable generation. This in turn
11508 may require further template instantiations. We place a limit here
11509 to avoid infinite loop. */
11510 if (pending_templates && retries >= max_tinst_depth)
11512 cp_error_at ("template instantiation depth exceeds maximum of %d"
11513 " (use -ftemplate-depth-NN to increase the maximum)"
11514 " instantiating %q+D, possibly from virtual table"
11516 max_tinst_depth, TREE_VALUE (pending_templates));
11524 t = &pending_templates;
11527 tree instantiation = TREE_VALUE (*t);
11529 reopen_tinst_level (TREE_PURPOSE (*t));
11531 if (TYPE_P (instantiation))
11535 if (!COMPLETE_TYPE_P (instantiation))
11537 instantiate_class_template (instantiation);
11538 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11539 for (fn = TYPE_METHODS (instantiation);
11541 fn = TREE_CHAIN (fn))
11542 if (! DECL_ARTIFICIAL (fn))
11543 instantiate_decl (fn, /*defer_ok=*/0,
11544 /*undefined_ok=*/0);
11545 if (COMPLETE_TYPE_P (instantiation))
11549 if (COMPLETE_TYPE_P (instantiation))
11550 /* If INSTANTIATION has been instantiated, then we don't
11551 need to consider it again in the future. */
11552 *t = TREE_CHAIN (*t);
11556 t = &TREE_CHAIN (*t);
11561 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11562 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11564 instantiation = instantiate_decl (instantiation,
11566 /*undefined_ok=*/0);
11567 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11571 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11572 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11573 /* If INSTANTIATION has been instantiated, then we don't
11574 need to consider it again in the future. */
11575 *t = TREE_CHAIN (*t);
11579 t = &TREE_CHAIN (*t);
11583 current_tinst_level = NULL_TREE;
11585 last_pending_template = last;
11587 while (reconsider);
11589 input_location = saved_loc;
11592 /* Substitute ARGVEC into T, which is a list of initializers for
11593 either base class or a non-static data member. The TREE_PURPOSEs
11594 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11595 instantiate_decl. */
11598 tsubst_initializer_list (tree t, tree argvec)
11600 tree inits = NULL_TREE;
11602 for (; t; t = TREE_CHAIN (t))
11607 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11609 decl = expand_member_init (decl);
11610 if (decl && !DECL_P (decl))
11611 in_base_initializer = 1;
11613 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11615 in_base_initializer = 0;
11619 init = build_tree_list (decl, init);
11620 TREE_CHAIN (init) = inits;
11627 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11630 set_current_access_from_decl (tree decl)
11632 if (TREE_PRIVATE (decl))
11633 current_access_specifier = access_private_node;
11634 else if (TREE_PROTECTED (decl))
11635 current_access_specifier = access_protected_node;
11637 current_access_specifier = access_public_node;
11640 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11641 is the instantiation (which should have been created with
11642 start_enum) and ARGS are the template arguments to use. */
11645 tsubst_enum (tree tag, tree newtag, tree args)
11649 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11654 decl = TREE_VALUE (e);
11655 /* Note that in a template enum, the TREE_VALUE is the
11656 CONST_DECL, not the corresponding INTEGER_CST. */
11657 value = tsubst_expr (DECL_INITIAL (decl),
11658 args, tf_error | tf_warning,
11661 /* Give this enumeration constant the correct access. */
11662 set_current_access_from_decl (decl);
11664 /* Actually build the enumerator itself. */
11665 build_enumerator (DECL_NAME (decl), value, newtag);
11668 finish_enum (newtag);
11669 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11670 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11673 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11674 its type -- but without substituting the innermost set of template
11675 arguments. So, innermost set of template parameters will appear in
11679 get_mostly_instantiated_function_type (tree decl)
11687 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11688 targs = DECL_TI_ARGS (decl);
11689 tparms = DECL_TEMPLATE_PARMS (tmpl);
11690 parm_depth = TMPL_PARMS_DEPTH (tparms);
11692 /* There should be as many levels of arguments as there are levels
11694 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11696 fn_type = TREE_TYPE (tmpl);
11698 if (parm_depth == 1)
11699 /* No substitution is necessary. */
11706 /* Replace the innermost level of the TARGS with NULL_TREEs to
11707 let tsubst know not to substitute for those parameters. */
11708 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11709 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11710 SET_TMPL_ARGS_LEVEL (partial_args, i,
11711 TMPL_ARGS_LEVEL (targs, i));
11712 SET_TMPL_ARGS_LEVEL (partial_args,
11713 TMPL_ARGS_DEPTH (targs),
11714 make_tree_vec (DECL_NTPARMS (tmpl)));
11716 /* Make sure that we can see identifiers, and compute access
11717 correctly. We can just use the context of DECL for the
11718 partial substitution here. It depends only on outer template
11719 parameters, regardless of whether the innermost level is
11720 specialized or not. */
11721 push_access_scope (decl);
11723 ++processing_template_decl;
11724 /* Now, do the (partial) substitution to figure out the
11725 appropriate function type. */
11726 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11727 --processing_template_decl;
11729 /* Substitute into the template parameters to obtain the real
11730 innermost set of parameters. This step is important if the
11731 innermost set of template parameters contains value
11732 parameters whose types depend on outer template parameters. */
11733 TREE_VEC_LENGTH (partial_args)--;
11734 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11736 pop_access_scope (decl);
11742 /* Return truthvalue if we're processing a template different from
11743 the last one involved in diagnostics. */
11745 problematic_instantiation_changed (void)
11747 return last_template_error_tick != tinst_level_tick;
11750 /* Remember current template involved in diagnostics. */
11752 record_last_problematic_instantiation (void)
11754 last_template_error_tick = tinst_level_tick;
11758 current_instantiation (void)
11760 return current_tinst_level;
11763 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11764 type. Return zero for ok, nonzero for disallowed. Issue error and
11765 warning messages under control of COMPLAIN. */
11768 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11770 if (INTEGRAL_TYPE_P (type))
11772 else if (POINTER_TYPE_P (type))
11774 else if (TYPE_PTR_TO_MEMBER_P (type))
11776 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11778 else if (TREE_CODE (type) == TYPENAME_TYPE)
11781 if (complain & tf_error)
11782 error ("%q#T is not a valid type for a template constant parameter", type);
11786 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11787 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11790 dependent_type_p_r (tree type)
11796 A type is dependent if it is:
11798 -- a template parameter. Template template parameters are types
11799 for us (since TYPE_P holds true for them) so we handle
11801 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11802 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11804 /* -- a qualified-id with a nested-name-specifier which contains a
11805 class-name that names a dependent type or whose unqualified-id
11806 names a dependent type. */
11807 if (TREE_CODE (type) == TYPENAME_TYPE)
11809 /* -- a cv-qualified type where the cv-unqualified type is
11811 type = TYPE_MAIN_VARIANT (type);
11812 /* -- a compound type constructed from any dependent type. */
11813 if (TYPE_PTR_TO_MEMBER_P (type))
11814 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11815 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11817 else if (TREE_CODE (type) == POINTER_TYPE
11818 || TREE_CODE (type) == REFERENCE_TYPE)
11819 return dependent_type_p (TREE_TYPE (type));
11820 else if (TREE_CODE (type) == FUNCTION_TYPE
11821 || TREE_CODE (type) == METHOD_TYPE)
11825 if (dependent_type_p (TREE_TYPE (type)))
11827 for (arg_type = TYPE_ARG_TYPES (type);
11829 arg_type = TREE_CHAIN (arg_type))
11830 if (dependent_type_p (TREE_VALUE (arg_type)))
11834 /* -- an array type constructed from any dependent type or whose
11835 size is specified by a constant expression that is
11836 value-dependent. */
11837 if (TREE_CODE (type) == ARRAY_TYPE)
11839 if (TYPE_DOMAIN (type)
11840 && ((value_dependent_expression_p
11841 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11842 || (type_dependent_expression_p
11843 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11845 return dependent_type_p (TREE_TYPE (type));
11848 /* -- a template-id in which either the template name is a template
11850 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11852 /* ... or any of the template arguments is a dependent type or
11853 an expression that is type-dependent or value-dependent. */
11854 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11855 && (any_dependent_template_arguments_p
11856 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11859 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11860 expression is not type-dependent, then it should already been
11862 if (TREE_CODE (type) == TYPEOF_TYPE)
11865 /* The standard does not specifically mention types that are local
11866 to template functions or local classes, but they should be
11867 considered dependent too. For example:
11869 template <int I> void f() {
11874 The size of `E' cannot be known until the value of `I' has been
11875 determined. Therefore, `E' must be considered dependent. */
11876 scope = TYPE_CONTEXT (type);
11877 if (scope && TYPE_P (scope))
11878 return dependent_type_p (scope);
11879 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11880 return type_dependent_expression_p (scope);
11882 /* Other types are non-dependent. */
11886 /* Returns TRUE if TYPE is dependent, in the sense of
11887 [temp.dep.type]. */
11890 dependent_type_p (tree type)
11892 /* If there are no template parameters in scope, then there can't be
11893 any dependent types. */
11894 if (!processing_template_decl)
11897 /* If the type is NULL, we have not computed a type for the entity
11898 in question; in that case, the type is dependent. */
11902 /* Erroneous types can be considered non-dependent. */
11903 if (type == error_mark_node)
11906 /* If we have not already computed the appropriate value for TYPE,
11908 if (!TYPE_DEPENDENT_P_VALID (type))
11910 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11911 TYPE_DEPENDENT_P_VALID (type) = 1;
11914 return TYPE_DEPENDENT_P (type);
11917 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11920 dependent_scope_ref_p (tree expression, bool criterion (tree))
11925 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
11927 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11930 scope = TREE_OPERAND (expression, 0);
11931 name = TREE_OPERAND (expression, 1);
11935 An id-expression is type-dependent if it contains a
11936 nested-name-specifier that contains a class-name that names a
11938 /* The suggested resolution to Core Issue 2 implies that if the
11939 qualifying type is the current class, then we must peek
11942 && currently_open_class (scope)
11943 && !criterion (name))
11945 if (dependent_type_p (scope))
11951 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11952 [temp.dep.constexpr] */
11955 value_dependent_expression_p (tree expression)
11957 if (!processing_template_decl)
11960 /* A name declared with a dependent type. */
11961 if (TREE_CODE (expression) == IDENTIFIER_NODE
11962 || (DECL_P (expression)
11963 && type_dependent_expression_p (expression)))
11965 /* A non-type template parameter. */
11966 if ((TREE_CODE (expression) == CONST_DECL
11967 && DECL_TEMPLATE_PARM_P (expression))
11968 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11970 /* A constant with integral or enumeration type and is initialized
11971 with an expression that is value-dependent. */
11972 if (TREE_CODE (expression) == VAR_DECL
11973 && DECL_INITIAL (expression)
11974 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11975 && value_dependent_expression_p (DECL_INITIAL (expression)))
11977 /* These expressions are value-dependent if the type to which the
11978 cast occurs is dependent or the expression being casted is
11979 value-dependent. */
11980 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11981 || TREE_CODE (expression) == STATIC_CAST_EXPR
11982 || TREE_CODE (expression) == CONST_CAST_EXPR
11983 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11984 || TREE_CODE (expression) == CAST_EXPR)
11986 tree type = TREE_TYPE (expression);
11987 if (dependent_type_p (type))
11989 /* A functional cast has a list of operands. */
11990 expression = TREE_OPERAND (expression, 0);
11993 /* If there are no operands, it must be an expression such
11994 as "int()". This should not happen for aggregate types
11995 because it would form non-constant expressions. */
11996 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12000 if (TREE_CODE (expression) == TREE_LIST)
12004 if (value_dependent_expression_p (TREE_VALUE (expression)))
12006 expression = TREE_CHAIN (expression);
12008 while (expression);
12012 return value_dependent_expression_p (expression);
12014 /* A `sizeof' expression is value-dependent if the operand is
12016 if (TREE_CODE (expression) == SIZEOF_EXPR
12017 || TREE_CODE (expression) == ALIGNOF_EXPR)
12019 expression = TREE_OPERAND (expression, 0);
12020 if (TYPE_P (expression))
12021 return dependent_type_p (expression);
12022 return type_dependent_expression_p (expression);
12024 if (TREE_CODE (expression) == SCOPE_REF)
12025 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12026 if (TREE_CODE (expression) == COMPONENT_REF)
12027 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12028 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12029 /* A constant expression is value-dependent if any subexpression is
12030 value-dependent. */
12031 if (EXPR_P (expression))
12033 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12036 return (value_dependent_expression_p
12037 (TREE_OPERAND (expression, 0)));
12038 case tcc_comparison:
12040 return ((value_dependent_expression_p
12041 (TREE_OPERAND (expression, 0)))
12042 || (value_dependent_expression_p
12043 (TREE_OPERAND (expression, 1))));
12044 case tcc_expression:
12047 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12048 /* In some cases, some of the operands may be missing.
12049 (For example, in the case of PREDECREMENT_EXPR, the
12050 amount to increment by may be missing.) That doesn't
12051 make the expression dependent. */
12052 if (TREE_OPERAND (expression, i)
12053 && (value_dependent_expression_p
12054 (TREE_OPERAND (expression, i))))
12058 case tcc_reference:
12059 case tcc_statement:
12060 /* These cannot be value dependent. */
12064 gcc_unreachable ();
12068 /* The expression is not value-dependent. */
12072 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12073 [temp.dep.expr]. */
12076 type_dependent_expression_p (tree expression)
12078 if (!processing_template_decl)
12081 if (expression == error_mark_node)
12084 /* An unresolved name is always dependent. */
12085 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12088 /* Some expression forms are never type-dependent. */
12089 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12090 || TREE_CODE (expression) == SIZEOF_EXPR
12091 || TREE_CODE (expression) == ALIGNOF_EXPR
12092 || TREE_CODE (expression) == TYPEID_EXPR
12093 || TREE_CODE (expression) == DELETE_EXPR
12094 || TREE_CODE (expression) == VEC_DELETE_EXPR
12095 || TREE_CODE (expression) == THROW_EXPR)
12098 /* The types of these expressions depends only on the type to which
12099 the cast occurs. */
12100 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12101 || TREE_CODE (expression) == STATIC_CAST_EXPR
12102 || TREE_CODE (expression) == CONST_CAST_EXPR
12103 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12104 || TREE_CODE (expression) == CAST_EXPR)
12105 return dependent_type_p (TREE_TYPE (expression));
12107 /* The types of these expressions depends only on the type created
12108 by the expression. */
12109 if (TREE_CODE (expression) == NEW_EXPR
12110 || TREE_CODE (expression) == VEC_NEW_EXPR)
12112 /* For NEW_EXPR tree nodes created inside a template, either
12113 the object type itself or a TREE_LIST may appear as the
12115 tree type = TREE_OPERAND (expression, 1);
12116 if (TREE_CODE (type) == TREE_LIST)
12117 /* This is an array type. We need to check array dimensions
12119 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12120 || value_dependent_expression_p
12121 (TREE_OPERAND (TREE_VALUE (type), 1));
12123 return dependent_type_p (type);
12126 if (TREE_CODE (expression) == SCOPE_REF
12127 && dependent_scope_ref_p (expression,
12128 type_dependent_expression_p))
12131 if (TREE_CODE (expression) == FUNCTION_DECL
12132 && DECL_LANG_SPECIFIC (expression)
12133 && DECL_TEMPLATE_INFO (expression)
12134 && (any_dependent_template_arguments_p
12135 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12138 if (TREE_CODE (expression) == TEMPLATE_DECL
12139 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12142 if (TREE_TYPE (expression) == unknown_type_node)
12144 if (TREE_CODE (expression) == ADDR_EXPR)
12145 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12146 if (TREE_CODE (expression) == COMPONENT_REF
12147 || TREE_CODE (expression) == OFFSET_REF)
12149 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12151 expression = TREE_OPERAND (expression, 1);
12152 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12155 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12156 if (TREE_CODE (expression) == SCOPE_REF)
12159 if (TREE_CODE (expression) == BASELINK)
12160 expression = BASELINK_FUNCTIONS (expression);
12162 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12164 if (any_dependent_template_arguments_p
12165 (TREE_OPERAND (expression, 1)))
12167 expression = TREE_OPERAND (expression, 0);
12169 gcc_assert (TREE_CODE (expression) == OVERLOAD);
12173 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12175 expression = OVL_NEXT (expression);
12180 return (dependent_type_p (TREE_TYPE (expression)));
12183 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12184 contains a type-dependent expression. */
12187 any_type_dependent_arguments_p (tree args)
12191 tree arg = TREE_VALUE (args);
12193 if (type_dependent_expression_p (arg))
12195 args = TREE_CHAIN (args);
12200 /* Returns TRUE if the ARG (a template argument) is dependent. */
12203 dependent_template_arg_p (tree arg)
12205 if (!processing_template_decl)
12208 if (TREE_CODE (arg) == TEMPLATE_DECL
12209 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12210 return dependent_template_p (arg);
12211 else if (TYPE_P (arg))
12212 return dependent_type_p (arg);
12214 return (type_dependent_expression_p (arg)
12215 || value_dependent_expression_p (arg));
12218 /* Returns true if ARGS (a collection of template arguments) contains
12219 any dependent arguments. */
12222 any_dependent_template_arguments_p (tree args)
12230 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12232 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12233 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12234 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12241 /* Returns TRUE if the template TMPL is dependent. */
12244 dependent_template_p (tree tmpl)
12246 if (TREE_CODE (tmpl) == OVERLOAD)
12250 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12252 tmpl = OVL_CHAIN (tmpl);
12257 /* Template template parameters are dependent. */
12258 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12259 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12261 /* So are names that have not been looked up. */
12262 if (TREE_CODE (tmpl) == SCOPE_REF
12263 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12265 /* So are member templates of dependent classes. */
12266 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12267 return dependent_type_p (DECL_CONTEXT (tmpl));
12271 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12274 dependent_template_id_p (tree tmpl, tree args)
12276 return (dependent_template_p (tmpl)
12277 || any_dependent_template_arguments_p (args));
12280 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12281 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12282 can be found. Note that this function peers inside uninstantiated
12283 templates and therefore should be used only in extremely limited
12287 resolve_typename_type (tree type, bool only_current_p)
12295 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12297 scope = TYPE_CONTEXT (type);
12298 name = TYPE_IDENTIFIER (type);
12300 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12301 it first before we can figure out what NAME refers to. */
12302 if (TREE_CODE (scope) == TYPENAME_TYPE)
12303 scope = resolve_typename_type (scope, only_current_p);
12304 /* If we don't know what SCOPE refers to, then we cannot resolve the
12306 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12307 return error_mark_node;
12308 /* If the SCOPE is a template type parameter, we have no way of
12309 resolving the name. */
12310 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12312 /* If the SCOPE is not the current instantiation, there's no reason
12313 to look inside it. */
12314 if (only_current_p && !currently_open_class (scope))
12315 return error_mark_node;
12316 /* If SCOPE is a partial instantiation, it will not have a valid
12317 TYPE_FIELDS list, so use the original template. */
12318 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12319 /* Enter the SCOPE so that name lookup will be resolved as if we
12320 were in the class definition. In particular, SCOPE will no
12321 longer be considered a dependent type. */
12322 pop_p = push_scope (scope);
12323 /* Look up the declaration. */
12324 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12325 /* Obtain the set of qualifiers applied to the TYPE. */
12326 quals = cp_type_quals (type);
12327 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12328 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12330 type = error_mark_node;
12331 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12332 && TREE_CODE (decl) == TYPE_DECL)
12333 type = TREE_TYPE (decl);
12334 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12335 && DECL_CLASS_TEMPLATE_P (decl))
12339 /* Obtain the template and the arguments. */
12340 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12341 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12342 /* Instantiate the template. */
12343 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12344 /*entering_scope=*/0, tf_error | tf_user);
12347 type = error_mark_node;
12348 /* Qualify the resulting type. */
12349 if (type != error_mark_node && quals)
12350 type = cp_build_qualified_type (type, quals);
12351 /* Leave the SCOPE. */
12358 /* EXPR is an expression which is not type-dependent. Return a proxy
12359 for EXPR that can be used to compute the types of larger
12360 expressions containing EXPR. */
12363 build_non_dependent_expr (tree expr)
12367 /* Preserve null pointer constants so that the type of things like
12368 "p == 0" where "p" is a pointer can be determined. */
12369 if (null_ptr_cst_p (expr))
12371 /* Preserve OVERLOADs; the functions must be available to resolve
12373 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12374 TREE_OPERAND (expr, 0) : expr);
12375 if (TREE_CODE (inner_expr) == OVERLOAD
12376 || TREE_CODE (inner_expr) == FUNCTION_DECL
12377 || TREE_CODE (inner_expr) == TEMPLATE_DECL
12378 || TREE_CODE (inner_expr) == TEMPLATE_ID_EXPR)
12380 /* There is no need to return a proxy for a variable. */
12381 if (TREE_CODE (expr) == VAR_DECL)
12383 /* Preserve string constants; conversions from string constants to
12384 "char *" are allowed, even though normally a "const char *"
12385 cannot be used to initialize a "char *". */
12386 if (TREE_CODE (expr) == STRING_CST)
12388 /* Preserve arithmetic constants, as an optimization -- there is no
12389 reason to create a new node. */
12390 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12392 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12393 There is at least one place where we want to know that a
12394 particular expression is a throw-expression: when checking a ?:
12395 expression, there are special rules if the second or third
12396 argument is a throw-expression. */
12397 if (TREE_CODE (expr) == THROW_EXPR)
12400 if (TREE_CODE (expr) == COND_EXPR)
12401 return build3 (COND_EXPR,
12403 TREE_OPERAND (expr, 0),
12404 (TREE_OPERAND (expr, 1)
12405 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12406 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12407 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12408 if (TREE_CODE (expr) == COMPOUND_EXPR
12409 && !COMPOUND_EXPR_OVERLOADED (expr))
12410 return build2 (COMPOUND_EXPR,
12412 TREE_OPERAND (expr, 0),
12413 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12415 /* Otherwise, build a NON_DEPENDENT_EXPR.
12417 REFERENCE_TYPEs are not stripped for expressions in templates
12418 because doing so would play havoc with mangling. Consider, for
12421 template <typename T> void f<T& g>() { g(); }
12423 In the body of "f", the expression for "g" will have
12424 REFERENCE_TYPE, even though the standard says that it should
12425 not. The reason is that we must preserve the syntactic form of
12426 the expression so that mangling (say) "f<g>" inside the body of
12427 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12429 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12432 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12433 Return a new TREE_LIST with the various arguments replaced with
12434 equivalent non-dependent expressions. */
12437 build_non_dependent_args (tree args)
12442 new_args = NULL_TREE;
12443 for (a = args; a; a = TREE_CHAIN (a))
12444 new_args = tree_cons (NULL_TREE,
12445 build_non_dependent_expr (TREE_VALUE (a)),
12447 return nreverse (new_args);
12450 #include "gt-cp-pt.h"