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);
1743 if (!processing_specialization)
1746 tsk = tsk_excessive_parms;
1749 tsk = current_tmpl_spec_kind (template_count);
1754 if (processing_specialization)
1757 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1759 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1762 /* This could be something like:
1764 template <class T> void f(T);
1765 class S { friend void f<>(int); } */
1769 /* This case handles bogus declarations like template <>
1770 template <class T> void f<int>(); */
1772 error ("template-id %qD in declaration of primary template",
1779 case tsk_invalid_member_spec:
1780 /* The error has already been reported in
1781 check_specialization_scope. */
1782 return error_mark_node;
1784 case tsk_invalid_expl_inst:
1785 error ("template parameter list used in explicit instantiation");
1791 error ("definition provided for explicit instantiation");
1793 explicit_instantiation = 1;
1796 case tsk_excessive_parms:
1797 case tsk_insufficient_parms:
1798 if (tsk == tsk_excessive_parms)
1799 error ("too many template parameter lists in declaration of %qD",
1801 else if (template_header_count)
1802 error("too few template parameter lists in declaration of %qD", decl);
1804 error("explicit specialization of %qD must be introduced by "
1805 "%<template <>%>", decl);
1809 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1811 member_specialization = 1;
1817 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1819 /* This case handles bogus declarations like template <>
1820 template <class T> void f<int>(); */
1822 if (uses_template_parms (declarator))
1823 error ("function template partial specialization %qD "
1824 "is not allowed", declarator);
1826 error ("template-id %qD in declaration of primary template",
1831 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1832 /* This is a specialization of a member template, without
1833 specialization the containing class. Something like:
1835 template <class T> struct S {
1836 template <class U> void f (U);
1838 template <> template <class U> void S<int>::f(U) {}
1840 That's a specialization -- but of the entire template. */
1848 if (specialization || member_specialization)
1850 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1851 for (; t; t = TREE_CHAIN (t))
1852 if (TREE_PURPOSE (t))
1855 ("default argument specified in explicit specialization");
1858 if (current_lang_name == lang_name_c)
1859 error ("template specialization with C linkage");
1862 if (specialization || member_specialization || explicit_instantiation)
1864 tree tmpl = NULL_TREE;
1865 tree targs = NULL_TREE;
1867 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1868 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1872 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1877 /* If there is no class context, the explicit instantiation
1878 must be at namespace scope. */
1879 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1881 /* Find the namespace binding, using the declaration
1883 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1886 declarator = lookup_template_function (fns, NULL_TREE);
1889 if (declarator == error_mark_node)
1890 return error_mark_node;
1892 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1894 if (!explicit_instantiation)
1895 /* A specialization in class scope. This is invalid,
1896 but the error will already have been flagged by
1897 check_specialization_scope. */
1898 return error_mark_node;
1901 /* It's not valid to write an explicit instantiation in
1904 class C { template void f(); }
1906 This case is caught by the parser. However, on
1909 template class C { void f(); };
1911 (which is invalid) we can get here. The error will be
1918 else if (ctype != NULL_TREE
1919 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1922 /* Find the list of functions in ctype that have the same
1923 name as the declared function. */
1924 tree name = TREE_OPERAND (declarator, 0);
1925 tree fns = NULL_TREE;
1928 if (constructor_name_p (name, ctype))
1930 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1932 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1933 : !TYPE_HAS_DESTRUCTOR (ctype))
1935 /* From [temp.expl.spec]:
1937 If such an explicit specialization for the member
1938 of a class template names an implicitly-declared
1939 special member function (clause _special_), the
1940 program is ill-formed.
1942 Similar language is found in [temp.explicit]. */
1943 error ("specialization of implicitly-declared special member function");
1944 return error_mark_node;
1947 name = is_constructor ? ctor_identifier : dtor_identifier;
1950 if (!DECL_CONV_FN_P (decl))
1952 idx = lookup_fnfields_1 (ctype, name);
1954 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1961 /* For a type-conversion operator, we cannot do a
1962 name-based lookup. We might be looking for `operator
1963 int' which will be a specialization of `operator T'.
1964 So, we find *all* the conversion operators, and then
1965 select from them. */
1968 methods = CLASSTYPE_METHOD_VEC (ctype);
1970 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1971 VEC_iterate (tree, methods, idx, ovl);
1974 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1975 /* There are no more conversion functions. */
1978 /* Glue all these conversion functions together
1979 with those we already have. */
1980 for (; ovl; ovl = OVL_NEXT (ovl))
1981 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1985 if (fns == NULL_TREE)
1987 error ("no member function %qD declared in %qT", name, ctype);
1988 return error_mark_node;
1991 TREE_OPERAND (declarator, 0) = fns;
1994 /* Figure out what exactly is being specialized at this point.
1995 Note that for an explicit instantiation, even one for a
1996 member function, we cannot tell apriori whether the
1997 instantiation is for a member template, or just a member
1998 function of a template class. Even if a member template is
1999 being instantiated, the member template arguments may be
2000 elided if they can be deduced from the rest of the
2002 tmpl = determine_specialization (declarator, decl,
2004 member_specialization,
2007 if (!tmpl || tmpl == error_mark_node)
2008 /* We couldn't figure out what this declaration was
2010 return error_mark_node;
2013 tree gen_tmpl = most_general_template (tmpl);
2015 if (explicit_instantiation)
2017 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2018 is done by do_decl_instantiation later. */
2020 int arg_depth = TMPL_ARGS_DEPTH (targs);
2021 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2023 if (arg_depth > parm_depth)
2025 /* If TMPL is not the most general template (for
2026 example, if TMPL is a friend template that is
2027 injected into namespace scope), then there will
2028 be too many levels of TARGS. Remove some of them
2033 new_targs = make_tree_vec (parm_depth);
2034 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2035 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2036 = TREE_VEC_ELT (targs, i);
2040 return instantiate_template (tmpl, targs, tf_error);
2043 /* If we thought that the DECL was a member function, but it
2044 turns out to be specializing a static member function,
2045 make DECL a static member function as well. */
2046 if (DECL_STATIC_FUNCTION_P (tmpl)
2047 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2048 revert_static_member_fn (decl);
2050 /* If this is a specialization of a member template of a
2051 template class. In we want to return the TEMPLATE_DECL,
2052 not the specialization of it. */
2053 if (tsk == tsk_template)
2055 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2056 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2059 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2060 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2061 = DECL_SOURCE_LOCATION (decl);
2066 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2067 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2069 /* Inherit default function arguments from the template
2070 DECL is specializing. */
2071 copy_default_args_to_explicit_spec (decl);
2073 /* This specialization has the same protection as the
2074 template it specializes. */
2075 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2076 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2078 if (is_friend && !have_def)
2079 /* This is not really a declaration of a specialization.
2080 It's just the name of an instantiation. But, it's not
2081 a request for an instantiation, either. */
2082 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2083 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2084 /* This is indeed a specialization. In case of constructors
2085 and destructors, we need in-charge and not-in-charge
2086 versions in V3 ABI. */
2087 clone_function_decl (decl, /*update_method_vec_p=*/0);
2089 /* Register this specialization so that we can find it
2091 decl = register_specialization (decl, gen_tmpl, targs);
2098 /* TYPE is being declared. Verify that the use of template headers
2099 and such is reasonable. Issue error messages if not. */
2102 maybe_check_template_type (tree type)
2104 if (template_header_count)
2106 /* We are in the scope of some `template <...>' header. */
2109 = template_class_depth_real (TYPE_CONTEXT (type),
2110 /*count_specializations=*/1);
2112 if (template_header_count <= context_depth)
2113 /* This is OK; the template headers are for the context. We
2114 are actually too lenient here; like
2115 check_explicit_specialization we should consider the number
2116 of template types included in the actual declaration. For
2119 template <class T> struct S {
2120 template <class U> template <class V>
2126 template <class T> struct S {
2127 template <class U> struct I;
2130 template <class T> template <class U.
2135 else if (template_header_count > context_depth + 1)
2136 /* There are two many template parameter lists. */
2137 error ("too many template parameter lists in declaration of %qT", type);
2141 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2142 parameters. These are represented in the same format used for
2143 DECL_TEMPLATE_PARMS. */
2146 comp_template_parms (tree parms1, tree parms2)
2151 if (parms1 == parms2)
2154 for (p1 = parms1, p2 = parms2;
2155 p1 != NULL_TREE && p2 != NULL_TREE;
2156 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2158 tree t1 = TREE_VALUE (p1);
2159 tree t2 = TREE_VALUE (p2);
2162 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2163 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2165 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2168 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2170 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2171 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2173 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2176 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2178 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2183 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2184 /* One set of parameters has more parameters lists than the
2191 /* Complain if DECL shadows a template parameter.
2193 [temp.local]: A template-parameter shall not be redeclared within its
2194 scope (including nested scopes). */
2197 check_template_shadow (tree decl)
2201 /* If we're not in a template, we can't possibly shadow a template
2203 if (!current_template_parms)
2206 /* Figure out what we're shadowing. */
2207 if (TREE_CODE (decl) == OVERLOAD)
2208 decl = OVL_CURRENT (decl);
2209 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2211 /* If there's no previous binding for this name, we're not shadowing
2212 anything, let alone a template parameter. */
2216 /* If we're not shadowing a template parameter, we're done. Note
2217 that OLDDECL might be an OVERLOAD (or perhaps even an
2218 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2220 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2223 /* We check for decl != olddecl to avoid bogus errors for using a
2224 name inside a class. We check TPFI to avoid duplicate errors for
2225 inline member templates. */
2227 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2230 cp_error_at ("declaration of %q#D", decl);
2231 cp_error_at (" shadows template parm %q#D", olddecl);
2234 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2235 ORIG_LEVEL, DECL, and TYPE. */
2238 build_template_parm_index (int index,
2244 tree t = make_node (TEMPLATE_PARM_INDEX);
2245 TEMPLATE_PARM_IDX (t) = index;
2246 TEMPLATE_PARM_LEVEL (t) = level;
2247 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2248 TEMPLATE_PARM_DECL (t) = decl;
2249 TREE_TYPE (t) = type;
2250 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2251 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2252 TREE_READONLY (t) = TREE_READONLY (decl);
2257 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2258 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2259 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2260 new one is created. */
2263 reduce_template_parm_level (tree index, tree type, int levels)
2265 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2266 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2267 != TEMPLATE_PARM_LEVEL (index) - levels))
2269 tree orig_decl = TEMPLATE_PARM_DECL (index);
2272 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2273 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2274 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2275 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2276 DECL_ARTIFICIAL (decl) = 1;
2277 SET_DECL_TEMPLATE_PARM_P (decl);
2279 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2280 TEMPLATE_PARM_LEVEL (index) - levels,
2281 TEMPLATE_PARM_ORIG_LEVEL (index),
2283 TEMPLATE_PARM_DESCENDANTS (index) = t;
2285 /* Template template parameters need this. */
2286 DECL_TEMPLATE_PARMS (decl)
2287 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2290 return TEMPLATE_PARM_DESCENDANTS (index);
2293 /* Process information from new template parameter NEXT and append it to the
2294 LIST being built. This new parameter is a non-type parameter iff
2295 IS_NON_TYPE is true. */
2298 process_template_parm (tree list, tree next, bool is_non_type)
2306 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2307 defval = TREE_PURPOSE (parm);
2311 tree p = TREE_VALUE (tree_last (list));
2313 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2314 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2316 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2324 parm = TREE_VALUE (parm);
2326 SET_DECL_TEMPLATE_PARM_P (parm);
2330 The top-level cv-qualifiers on the template-parameter are
2331 ignored when determining its type. */
2332 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2334 /* A template parameter is not modifiable. */
2335 TREE_CONSTANT (parm) = 1;
2336 TREE_INVARIANT (parm) = 1;
2337 TREE_READONLY (parm) = 1;
2338 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2339 TREE_TYPE (parm) = void_type_node;
2340 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2341 TREE_CONSTANT (decl) = 1;
2342 TREE_INVARIANT (decl) = 1;
2343 TREE_READONLY (decl) = 1;
2344 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2345 = build_template_parm_index (idx, processing_template_decl,
2346 processing_template_decl,
2347 decl, TREE_TYPE (parm));
2352 parm = TREE_VALUE (TREE_VALUE (parm));
2354 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2356 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2357 /* This is for distinguishing between real templates and template
2358 template parameters */
2359 TREE_TYPE (parm) = t;
2360 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2365 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2366 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2367 decl = build_decl (TYPE_DECL, parm, t);
2370 TYPE_NAME (t) = decl;
2371 TYPE_STUB_DECL (t) = decl;
2373 TEMPLATE_TYPE_PARM_INDEX (t)
2374 = build_template_parm_index (idx, processing_template_decl,
2375 processing_template_decl,
2376 decl, TREE_TYPE (parm));
2378 DECL_ARTIFICIAL (decl) = 1;
2379 SET_DECL_TEMPLATE_PARM_P (decl);
2381 parm = build_tree_list (defval, parm);
2382 return chainon (list, parm);
2385 /* The end of a template parameter list has been reached. Process the
2386 tree list into a parameter vector, converting each parameter into a more
2387 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2391 end_template_parm_list (tree parms)
2395 tree saved_parmlist = make_tree_vec (list_length (parms));
2397 current_template_parms
2398 = tree_cons (size_int (processing_template_decl),
2399 saved_parmlist, current_template_parms);
2401 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2403 next = TREE_CHAIN (parm);
2404 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2405 TREE_CHAIN (parm) = NULL_TREE;
2408 --processing_template_parmlist;
2410 return saved_parmlist;
2413 /* end_template_decl is called after a template declaration is seen. */
2416 end_template_decl (void)
2418 reset_specialization ();
2420 if (! processing_template_decl)
2423 /* This matches the pushlevel in begin_template_parm_list. */
2426 --processing_template_decl;
2427 current_template_parms = TREE_CHAIN (current_template_parms);
2430 /* Given a template argument vector containing the template PARMS.
2431 The innermost PARMS are given first. */
2434 current_template_args (void)
2437 tree args = NULL_TREE;
2438 int length = TMPL_PARMS_DEPTH (current_template_parms);
2441 /* If there is only one level of template parameters, we do not
2442 create a TREE_VEC of TREE_VECs. Instead, we return a single
2443 TREE_VEC containing the arguments. */
2445 args = make_tree_vec (length);
2447 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2449 tree a = copy_node (TREE_VALUE (header));
2452 TREE_TYPE (a) = NULL_TREE;
2453 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2455 tree t = TREE_VEC_ELT (a, i);
2457 /* T will be a list if we are called from within a
2458 begin/end_template_parm_list pair, but a vector directly
2459 if within a begin/end_member_template_processing pair. */
2460 if (TREE_CODE (t) == TREE_LIST)
2464 if (TREE_CODE (t) == TYPE_DECL
2465 || TREE_CODE (t) == TEMPLATE_DECL)
2468 t = DECL_INITIAL (t);
2469 TREE_VEC_ELT (a, i) = t;
2474 TREE_VEC_ELT (args, --l) = a;
2482 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2483 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2484 a member template. Used by push_template_decl below. */
2487 build_template_decl (tree decl, tree parms, bool member_template_p)
2489 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2490 DECL_TEMPLATE_PARMS (tmpl) = parms;
2491 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2492 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2493 if (DECL_LANG_SPECIFIC (decl))
2495 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2496 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2497 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2498 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2499 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2500 if (DECL_OVERLOADED_OPERATOR_P (decl))
2501 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2502 DECL_OVERLOADED_OPERATOR_P (decl));
2508 struct template_parm_data
2510 /* The level of the template parameters we are currently
2514 /* The index of the specialization argument we are currently
2518 /* An array whose size is the number of template parameters. The
2519 elements are nonzero if the parameter has been used in any one
2520 of the arguments processed so far. */
2523 /* An array whose size is the number of template arguments. The
2524 elements are nonzero if the argument makes use of template
2525 parameters of this level. */
2526 int* arg_uses_template_parms;
2529 /* Subroutine of push_template_decl used to see if each template
2530 parameter in a partial specialization is used in the explicit
2531 argument list. If T is of the LEVEL given in DATA (which is
2532 treated as a template_parm_data*), then DATA->PARMS is marked
2536 mark_template_parm (tree t, void* data)
2540 struct template_parm_data* tpd = (struct template_parm_data*) data;
2542 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2544 level = TEMPLATE_PARM_LEVEL (t);
2545 idx = TEMPLATE_PARM_IDX (t);
2549 level = TEMPLATE_TYPE_LEVEL (t);
2550 idx = TEMPLATE_TYPE_IDX (t);
2553 if (level == tpd->level)
2555 tpd->parms[idx] = 1;
2556 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2559 /* Return zero so that for_each_template_parm will continue the
2560 traversal of the tree; we want to mark *every* template parm. */
2564 /* Process the partial specialization DECL. */
2567 process_partial_specialization (tree decl)
2569 tree type = TREE_TYPE (decl);
2570 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2571 tree specargs = CLASSTYPE_TI_ARGS (type);
2572 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2573 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2574 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2575 int nargs = TREE_VEC_LENGTH (inner_args);
2576 int ntparms = TREE_VEC_LENGTH (inner_parms);
2578 int did_error_intro = 0;
2579 struct template_parm_data tpd;
2580 struct template_parm_data tpd2;
2582 /* We check that each of the template parameters given in the
2583 partial specialization is used in the argument list to the
2584 specialization. For example:
2586 template <class T> struct S;
2587 template <class T> struct S<T*>;
2589 The second declaration is OK because `T*' uses the template
2590 parameter T, whereas
2592 template <class T> struct S<int>;
2594 is no good. Even trickier is:
2605 The S2<T> declaration is actually invalid; it is a
2606 full-specialization. Of course,
2609 struct S2<T (*)(U)>;
2611 or some such would have been OK. */
2612 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2613 tpd.parms = alloca (sizeof (int) * ntparms);
2614 memset (tpd.parms, 0, sizeof (int) * ntparms);
2616 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2617 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2618 for (i = 0; i < nargs; ++i)
2620 tpd.current_arg = i;
2621 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2622 &mark_template_parm,
2626 for (i = 0; i < ntparms; ++i)
2627 if (tpd.parms[i] == 0)
2629 /* One of the template parms was not used in the
2631 if (!did_error_intro)
2633 error ("template parameters not used in partial specialization:");
2634 did_error_intro = 1;
2637 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2640 /* [temp.class.spec]
2642 The argument list of the specialization shall not be identical to
2643 the implicit argument list of the primary template. */
2644 if (comp_template_args
2646 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2648 error ("partial specialization %qT does not specialize any template arguments", type);
2650 /* [temp.class.spec]
2652 A partially specialized non-type argument expression shall not
2653 involve template parameters of the partial specialization except
2654 when the argument expression is a simple identifier.
2656 The type of a template parameter corresponding to a specialized
2657 non-type argument shall not be dependent on a parameter of the
2659 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2661 for (i = 0; i < nargs; ++i)
2663 tree arg = TREE_VEC_ELT (inner_args, i);
2664 if (/* These first two lines are the `non-type' bit. */
2666 && TREE_CODE (arg) != TEMPLATE_DECL
2667 /* This next line is the `argument expression is not just a
2668 simple identifier' condition and also the `specialized
2669 non-type argument' bit. */
2670 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2672 if (tpd.arg_uses_template_parms[i])
2673 error ("template argument %qE involves template parameter(s)", arg);
2676 /* Look at the corresponding template parameter,
2677 marking which template parameters its type depends
2680 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2685 /* We haven't yet initialized TPD2. Do so now. */
2686 tpd2.arg_uses_template_parms
2687 = alloca (sizeof (int) * nargs);
2688 /* The number of parameters here is the number in the
2689 main template, which, as checked in the assertion
2691 tpd2.parms = alloca (sizeof (int) * nargs);
2693 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2696 /* Mark the template parameters. But this time, we're
2697 looking for the template parameters of the main
2698 template, not in the specialization. */
2699 tpd2.current_arg = i;
2700 tpd2.arg_uses_template_parms[i] = 0;
2701 memset (tpd2.parms, 0, sizeof (int) * nargs);
2702 for_each_template_parm (type,
2703 &mark_template_parm,
2707 if (tpd2.arg_uses_template_parms [i])
2709 /* The type depended on some template parameters.
2710 If they are fully specialized in the
2711 specialization, that's OK. */
2713 for (j = 0; j < nargs; ++j)
2714 if (tpd2.parms[j] != 0
2715 && tpd.arg_uses_template_parms [j])
2717 error ("type %qT of template argument %qE depends "
2718 "on template parameter(s)",
2728 if (retrieve_specialization (maintmpl, specargs,
2729 /*class_specializations_p=*/true))
2730 /* We've already got this specialization. */
2733 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2734 = tree_cons (inner_args, inner_parms,
2735 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2736 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2740 /* Check that a template declaration's use of default arguments is not
2741 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2742 nonzero if DECL is the thing declared by a primary template.
2743 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2746 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2749 int last_level_to_check;
2754 A default template-argument shall not be specified in a
2755 function template declaration or a function template definition, nor
2756 in the template-parameter-list of the definition of a member of a
2759 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2760 /* You can't have a function template declaration in a local
2761 scope, nor you can you define a member of a class template in a
2765 if (current_class_type
2766 && !TYPE_BEING_DEFINED (current_class_type)
2767 && DECL_LANG_SPECIFIC (decl)
2768 /* If this is either a friend defined in the scope of the class
2769 or a member function. */
2770 && (DECL_FUNCTION_MEMBER_P (decl)
2771 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2772 : DECL_FRIEND_CONTEXT (decl)
2773 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2775 /* And, if it was a member function, it really was defined in
2776 the scope of the class. */
2777 && (!DECL_FUNCTION_MEMBER_P (decl)
2778 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2779 /* We already checked these parameters when the template was
2780 declared, so there's no need to do it again now. This function
2781 was defined in class scope, but we're processing it's body now
2782 that the class is complete. */
2787 If a template-parameter has a default template-argument, all
2788 subsequent template-parameters shall have a default
2789 template-argument supplied. */
2790 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2792 tree inner_parms = TREE_VALUE (parm_level);
2793 int ntparms = TREE_VEC_LENGTH (inner_parms);
2794 int seen_def_arg_p = 0;
2797 for (i = 0; i < ntparms; ++i)
2799 tree parm = TREE_VEC_ELT (inner_parms, i);
2800 if (TREE_PURPOSE (parm))
2802 else if (seen_def_arg_p)
2804 error ("no default argument for %qD", TREE_VALUE (parm));
2805 /* For better subsequent error-recovery, we indicate that
2806 there should have been a default argument. */
2807 TREE_PURPOSE (parm) = error_mark_node;
2812 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2813 /* For an ordinary class template, default template arguments are
2814 allowed at the innermost level, e.g.:
2815 template <class T = int>
2817 but, in a partial specialization, they're not allowed even
2818 there, as we have in [temp.class.spec]:
2820 The template parameter list of a specialization shall not
2821 contain default template argument values.
2823 So, for a partial specialization, or for a function template,
2824 we look at all of them. */
2827 /* But, for a primary class template that is not a partial
2828 specialization we look at all template parameters except the
2830 parms = TREE_CHAIN (parms);
2832 /* Figure out what error message to issue. */
2833 if (TREE_CODE (decl) == FUNCTION_DECL)
2834 msg = "default template arguments may not be used in function templates";
2835 else if (is_partial)
2836 msg = "default template arguments may not be used in partial specializations";
2838 msg = "default argument for template parameter for class enclosing %qD";
2840 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2841 /* If we're inside a class definition, there's no need to
2842 examine the parameters to the class itself. On the one
2843 hand, they will be checked when the class is defined, and,
2844 on the other, default arguments are valid in things like:
2845 template <class T = double>
2846 struct S { template <class U> void f(U); };
2847 Here the default argument for `S' has no bearing on the
2848 declaration of `f'. */
2849 last_level_to_check = template_class_depth (current_class_type) + 1;
2851 /* Check everything. */
2852 last_level_to_check = 0;
2854 for (parm_level = parms;
2855 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2856 parm_level = TREE_CHAIN (parm_level))
2858 tree inner_parms = TREE_VALUE (parm_level);
2862 ntparms = TREE_VEC_LENGTH (inner_parms);
2863 for (i = 0; i < ntparms; ++i)
2864 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2872 /* Clear out the default argument so that we are not
2874 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2877 /* At this point, if we're still interested in issuing messages,
2878 they must apply to classes surrounding the object declared. */
2880 msg = "default argument for template parameter for class enclosing %qD";
2884 /* Worker for push_template_decl_real, called via
2885 for_each_template_parm. DATA is really an int, indicating the
2886 level of the parameters we are interested in. If T is a template
2887 parameter of that level, return nonzero. */
2890 template_parm_this_level_p (tree t, void* data)
2892 int this_level = *(int *)data;
2895 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2896 level = TEMPLATE_PARM_LEVEL (t);
2898 level = TEMPLATE_TYPE_LEVEL (t);
2899 return level == this_level;
2902 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2903 parameters given by current_template_args, or reuses a
2904 previously existing one, if appropriate. Returns the DECL, or an
2905 equivalent one, if it is replaced via a call to duplicate_decls.
2907 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2910 push_template_decl_real (tree decl, int is_friend)
2918 int new_template_p = 0;
2919 /* True if the template is a member template, in the sense of
2921 bool member_template_p = false;
2923 if (decl == error_mark_node)
2926 /* See if this is a partial specialization. */
2927 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2928 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2929 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2931 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2934 /* For a friend, we want the context of the friend function, not
2935 the type of which it is a friend. */
2936 ctx = DECL_CONTEXT (decl);
2937 else if (CP_DECL_CONTEXT (decl)
2938 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2939 /* In the case of a virtual function, we want the class in which
2941 ctx = CP_DECL_CONTEXT (decl);
2943 /* Otherwise, if we're currently defining some class, the DECL
2944 is assumed to be a member of the class. */
2945 ctx = current_scope ();
2947 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2950 if (!DECL_CONTEXT (decl))
2951 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2953 /* See if this is a primary template. */
2954 primary = template_parm_scope_p ();
2958 if (DECL_CLASS_SCOPE_P (decl))
2959 member_template_p = true;
2960 if (current_lang_name == lang_name_c)
2961 error ("template with C linkage");
2962 else if (TREE_CODE (decl) == TYPE_DECL
2963 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2964 error ("template class without a name");
2965 else if (TREE_CODE (decl) == FUNCTION_DECL)
2967 if (DECL_DESTRUCTOR_P (decl))
2971 A destructor shall not be a member template. */
2972 error ("destructor %qD declared as member template", decl);
2973 return error_mark_node;
2975 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2976 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2977 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2978 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2979 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2980 == void_list_node)))
2982 /* [basic.stc.dynamic.allocation]
2984 An allocation function can be a function
2985 template. ... Template allocation functions shall
2986 have two or more parameters. */
2987 error ("invalid template declaration of %qD", decl);
2991 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2992 && CLASS_TYPE_P (TREE_TYPE (decl)))
2993 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx)))
2997 error ("template declaration of %q#D", decl);
2998 return error_mark_node;
3002 /* Check to see that the rules regarding the use of default
3003 arguments are not being violated. */
3004 check_default_tmpl_args (decl, current_template_parms,
3005 primary, is_partial);
3008 return process_partial_specialization (decl);
3010 args = current_template_args ();
3013 || TREE_CODE (ctx) == FUNCTION_DECL
3014 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3015 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3017 if (DECL_LANG_SPECIFIC (decl)
3018 && DECL_TEMPLATE_INFO (decl)
3019 && DECL_TI_TEMPLATE (decl))
3020 tmpl = DECL_TI_TEMPLATE (decl);
3021 /* If DECL is a TYPE_DECL for a class-template, then there won't
3022 be DECL_LANG_SPECIFIC. The information equivalent to
3023 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3024 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3025 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3026 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3028 /* Since a template declaration already existed for this
3029 class-type, we must be redeclaring it here. Make sure
3030 that the redeclaration is valid. */
3031 redeclare_class_template (TREE_TYPE (decl),
3032 current_template_parms);
3033 /* We don't need to create a new TEMPLATE_DECL; just use the
3034 one we already had. */
3035 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3039 tmpl = build_template_decl (decl, current_template_parms,
3043 if (DECL_LANG_SPECIFIC (decl)
3044 && DECL_TEMPLATE_SPECIALIZATION (decl))
3046 /* A specialization of a member template of a template
3048 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3049 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3050 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3056 tree a, t, current, parms;
3059 if (TREE_CODE (decl) == TYPE_DECL)
3061 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3062 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3063 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3064 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3065 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3068 error ("%qD does not declare a template type", decl);
3072 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3074 error ("template definition of non-template %q#D", decl);
3078 tmpl = DECL_TI_TEMPLATE (decl);
3080 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3081 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3082 && DECL_TEMPLATE_SPECIALIZATION (decl)
3083 && DECL_MEMBER_TEMPLATE_P (tmpl))
3087 /* The declaration is a specialization of a member
3088 template, declared outside the class. Therefore, the
3089 innermost template arguments will be NULL, so we
3090 replace them with the arguments determined by the
3091 earlier call to check_explicit_specialization. */
3092 args = DECL_TI_ARGS (decl);
3095 = build_template_decl (decl, current_template_parms,
3097 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3098 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3099 DECL_TI_TEMPLATE (decl) = new_tmpl;
3100 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3101 DECL_TEMPLATE_INFO (new_tmpl)
3102 = tree_cons (tmpl, args, NULL_TREE);
3104 register_specialization (new_tmpl,
3105 most_general_template (tmpl),
3110 /* Make sure the template headers we got make sense. */
3112 parms = DECL_TEMPLATE_PARMS (tmpl);
3113 i = TMPL_PARMS_DEPTH (parms);
3114 if (TMPL_ARGS_DEPTH (args) != i)
3116 error ("expected %d levels of template parms for %q#D, got %d",
3117 i, decl, TMPL_ARGS_DEPTH (args));
3120 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3122 a = TMPL_ARGS_LEVEL (args, i);
3123 t = INNERMOST_TEMPLATE_PARMS (parms);
3125 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3127 if (current == decl)
3128 error ("got %d template parameters for %q#D",
3129 TREE_VEC_LENGTH (a), decl);
3131 error ("got %d template parameters for %q#T",
3132 TREE_VEC_LENGTH (a), current);
3133 error (" but %d required", TREE_VEC_LENGTH (t));
3136 /* Perhaps we should also check that the parms are used in the
3137 appropriate qualifying scopes in the declarator? */
3139 if (current == decl)
3142 current = TYPE_CONTEXT (current);
3146 DECL_TEMPLATE_RESULT (tmpl) = decl;
3147 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3149 /* Push template declarations for global functions and types. Note
3150 that we do not try to push a global template friend declared in a
3151 template class; such a thing may well depend on the template
3152 parameters of the class. */
3153 if (new_template_p && !ctx
3154 && !(is_friend && template_class_depth (current_class_type) > 0))
3156 tmpl = pushdecl_namespace_level (tmpl);
3157 if (tmpl == error_mark_node)
3158 return error_mark_node;
3163 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3164 if (DECL_CONV_FN_P (tmpl))
3166 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3168 /* It is a conversion operator. See if the type converted to
3169 depends on innermost template operands. */
3171 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3173 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3177 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3178 back to its most general template. If TMPL is a specialization,
3179 ARGS may only have the innermost set of arguments. Add the missing
3180 argument levels if necessary. */
3181 if (DECL_TEMPLATE_INFO (tmpl))
3182 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3184 info = tree_cons (tmpl, args, NULL_TREE);
3186 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3188 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3189 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3190 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3191 /* Don't change the name if we've already set it up. */
3192 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3193 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3195 else if (DECL_LANG_SPECIFIC (decl))
3196 DECL_TEMPLATE_INFO (decl) = info;
3198 return DECL_TEMPLATE_RESULT (tmpl);
3202 push_template_decl (tree decl)
3204 return push_template_decl_real (decl, 0);
3207 /* Called when a class template TYPE is redeclared with the indicated
3208 template PARMS, e.g.:
3210 template <class T> struct S;
3211 template <class T> struct S {}; */
3214 redeclare_class_template (tree type, tree parms)
3220 if (!TYPE_TEMPLATE_INFO (type))
3222 error ("%qT is not a template type", type);
3226 tmpl = TYPE_TI_TEMPLATE (type);
3227 if (!PRIMARY_TEMPLATE_P (tmpl))
3228 /* The type is nested in some template class. Nothing to worry
3229 about here; there are no new template parameters for the nested
3233 parms = INNERMOST_TEMPLATE_PARMS (parms);
3234 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3236 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3238 cp_error_at ("previous declaration %qD", tmpl);
3239 error ("used %d template parameter%s instead of %d",
3240 TREE_VEC_LENGTH (tmpl_parms),
3241 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
3242 TREE_VEC_LENGTH (parms));
3246 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3248 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3249 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3250 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3251 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3253 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3255 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3256 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3257 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3259 cp_error_at ("template parameter %q#D", tmpl_parm);
3260 error ("redeclared here as %q#D", parm);
3264 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3266 /* We have in [temp.param]:
3268 A template-parameter may not be given default arguments
3269 by two different declarations in the same scope. */
3270 error ("redefinition of default argument for %q#D", parm);
3271 error ("%J original definition appeared here", tmpl_parm);
3275 if (parm_default != NULL_TREE)
3276 /* Update the previous template parameters (which are the ones
3277 that will really count) with the new default value. */
3278 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3279 else if (tmpl_default != NULL_TREE)
3280 /* Update the new parameters, too; they'll be used as the
3281 parameters for any members. */
3282 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3286 /* Simplify EXPR if it is a non-dependent expression. Returns the
3287 (possibly simplified) expression. */
3290 fold_non_dependent_expr (tree expr)
3292 /* If we're in a template, but EXPR isn't value dependent, simplify
3293 it. We're supposed to treat:
3295 template <typename T> void f(T[1 + 1]);
3296 template <typename T> void f(T[2]);
3298 as two declarations of the same function, for example. */
3299 if (processing_template_decl
3300 && !type_dependent_expression_p (expr)
3301 && !value_dependent_expression_p (expr))
3303 HOST_WIDE_INT saved_processing_template_decl;
3305 saved_processing_template_decl = processing_template_decl;
3306 processing_template_decl = 0;
3307 expr = tsubst_copy_and_build (expr,
3310 /*in_decl=*/NULL_TREE,
3311 /*function_p=*/false);
3312 processing_template_decl = saved_processing_template_decl;
3317 /* EXPR is an expression which is used in a constant-expression context.
3318 For instance, it could be a VAR_DECL with a constant initializer.
3319 Extract the innest constant expression.
3321 This is basically a more powerful version of
3322 integral_constant_value, which can be used also in templates where
3323 initializers can maintain a syntactic rather than semantic form
3324 (even if they are non-dependent, for access-checking purposes). */
3327 fold_decl_constant_value (tree expr)
3331 tree const_expr = integral_constant_value (expr);
3332 if (expr == const_expr)
3334 expr = fold_non_dependent_expr (const_expr);
3340 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3341 must be a function or a pointer-to-function type, as specified
3342 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3343 and check that the resulting function has external linkage. */
3346 convert_nontype_argument_function (tree type, tree expr)
3351 fn = instantiate_type (type, fns, tf_none);
3352 if (fn == error_mark_node)
3353 return error_mark_node;
3356 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3357 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3359 /* [temp.arg.nontype]/1
3361 A template-argument for a non-type, non-template template-parameter
3364 -- the address of an object or function with external linkage. */
3365 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3367 error ("%qE is not a valid template argument for type %qT "
3368 "because function %qD has not external linkage",
3369 expr, type, fn_no_ptr);
3376 /* Attempt to convert the non-type template parameter EXPR to the
3377 indicated TYPE. If the conversion is successful, return the
3378 converted value. If the conversion is unsuccessful, return
3379 NULL_TREE if we issued an error message, or error_mark_node if we
3380 did not. We issue error messages for out-and-out bad template
3381 parameters, but not simply because the conversion failed, since we
3382 might be just trying to do argument deduction. Both TYPE and EXPR
3383 must be non-dependent.
3385 The conversion follows the special rules described in
3386 [temp.arg.nontype], and it is much more strict than an implicit
3389 This function is called twice for each template argument (see
3390 lookup_template_class for a more accurate description of this
3391 problem). This means that we need to handle expressions which
3392 are not valid in a C++ source, but can be created from the
3393 first call (for instance, casts to perform conversions). These
3394 hacks can go away after we fix the double coercion problem. */
3397 convert_nontype_argument (tree type, tree expr)
3401 /* Detect immediately string literals as invalid non-type argument.
3402 This special-case is not needed for correctness (we would easily
3403 catch this later), but only to provide better diagnostic for this
3404 common user mistake. As suggested by DR 100, we do not mention
3405 linkage issues in the diagnostic as this is not the point. */
3406 if (TREE_CODE (expr) == STRING_CST)
3408 error ("%qE is not a valid template argument for type %qT "
3409 "because string literals can never be used in this context",
3414 /* If we are in a template, EXPR may be non-dependent, but still
3415 have a syntactic, rather than semantic, form. For example, EXPR
3416 might be a SCOPE_REF, rather than the VAR_DECL to which the
3417 SCOPE_REF refers. Preserving the qualifying scope is necessary
3418 so that access checking can be performed when the template is
3419 instantiated -- but here we need the resolved form so that we can
3420 convert the argument. */
3421 expr = fold_non_dependent_expr (expr);
3422 expr_type = TREE_TYPE (expr);
3424 /* HACK: Due to double coercion, we can get a
3425 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3426 which is the tree that we built on the first call (see
3427 below when coercing to reference to object or to reference to
3428 function). We just strip everything and get to the arg.
3429 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3431 if (TREE_CODE (expr) == NOP_EXPR)
3433 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3435 /* ??? Maybe we could use convert_from_reference here, but we
3436 would need to relax its constraints because the NOP_EXPR
3437 could actually change the type to something more cv-qualified,
3438 and this is not folded by convert_from_reference. */
3439 tree addr = TREE_OPERAND (expr, 0);
3440 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3441 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3442 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3443 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3444 (TREE_TYPE (expr_type),
3445 TREE_TYPE (TREE_TYPE (addr))));
3447 expr = TREE_OPERAND (addr, 0);
3448 expr_type = TREE_TYPE (expr);
3451 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3452 parameter is a pointer to object, through decay and
3453 qualification conversion. Let's strip everything. */
3454 else if (TYPE_PTROBV_P (type))
3457 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3458 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3459 /* Skip the ADDR_EXPR only if it is part of the decay for
3460 an array. Otherwise, it is part of the original argument
3461 in the source code. */
3462 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3463 expr = TREE_OPERAND (expr, 0);
3464 expr_type = TREE_TYPE (expr);
3468 /* [temp.arg.nontype]/5, bullet 1
3470 For a non-type template-parameter of integral or enumeration type,
3471 integral promotions (_conv.prom_) and integral conversions
3472 (_conv.integral_) are applied. */
3473 if (INTEGRAL_TYPE_P (type))
3475 if (!INTEGRAL_TYPE_P (expr_type))
3476 return error_mark_node;
3478 expr = fold_decl_constant_value (expr);
3479 /* Notice that there are constant expressions like '4 % 0' which
3480 do not fold into integer constants. */
3481 if (TREE_CODE (expr) != INTEGER_CST)
3483 error ("%qE is not a valid template argument for type %qT "
3484 "because it is a non-constant expression", expr, type);
3488 /* At this point, an implicit conversion does what we want,
3489 because we already know that the expression is of integral
3491 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3492 if (expr == error_mark_node)
3493 return error_mark_node;
3495 /* Conversion was allowed: fold it to a bare integer constant. */
3498 /* [temp.arg.nontype]/5, bullet 2
3500 For a non-type template-parameter of type pointer to object,
3501 qualification conversions (_conv.qual_) and the array-to-pointer
3502 conversion (_conv.array_) are applied. */
3503 else if (TYPE_PTROBV_P (type))
3505 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3507 A template-argument for a non-type, non-template template-parameter
3508 shall be one of: [...]
3510 -- the name of a non-type template-parameter;
3511 -- the address of an object or function with external linkage, [...]
3512 expressed as "& id-expression" where the & is optional if the name
3513 refers to a function or array, or if the corresponding
3514 template-parameter is a reference.
3516 Here, we do not care about functions, as they are invalid anyway
3517 for a parameter of type pointer-to-object. */
3518 bool constant_address_p =
3519 (TREE_CODE (expr) == ADDR_EXPR
3520 || TREE_CODE (expr_type) == ARRAY_TYPE
3521 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3523 expr = decay_conversion (expr);
3524 if (expr == error_mark_node)
3525 return error_mark_node;
3527 expr = perform_qualification_conversions (type, expr);
3528 if (expr == error_mark_node)
3529 return error_mark_node;
3531 if (!constant_address_p)
3533 error ("%qE is not a valid template argument for type %qT "
3534 "because it is not a constant pointer", expr, type);
3538 /* [temp.arg.nontype]/5, bullet 3
3540 For a non-type template-parameter of type reference to object, no
3541 conversions apply. The type referred to by the reference may be more
3542 cv-qualified than the (otherwise identical) type of the
3543 template-argument. The template-parameter is bound directly to the
3544 template-argument, which must be an lvalue. */
3545 else if (TYPE_REF_OBJ_P (type))
3547 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3549 return error_mark_node;
3551 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3553 error ("%qE is not a valid template argument for type %qT "
3554 "because of conflicts in cv-qualification", expr, type);
3558 if (!real_lvalue_p (expr))
3560 error ("%qE is not a valid template argument for type %qT "
3561 "because it is not a lvalue", expr, type);
3565 /* [temp.arg.nontype]/1
3567 A template-argument for a non-type, non-template template-parameter
3568 shall be one of: [...]
3570 -- the address of an object or function with external linkage. */
3571 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3573 error ("%qE is not a valid template argument for type %qT "
3574 "because object %qD has not external linkage",
3579 expr = build_nop (type, build_address (expr));
3581 /* [temp.arg.nontype]/5, bullet 4
3583 For a non-type template-parameter of type pointer to function, only
3584 the function-to-pointer conversion (_conv.func_) is applied. If the
3585 template-argument represents a set of overloaded functions (or a
3586 pointer to such), the matching function is selected from the set
3588 else if (TYPE_PTRFN_P (type))
3590 /* If the argument is a template-id, we might not have enough
3591 context information to decay the pointer.
3592 ??? Why static5.C requires decay and subst1.C works fine
3594 if (!type_unknown_p (expr_type))
3596 expr = decay_conversion (expr);
3597 if (expr == error_mark_node)
3598 return error_mark_node;
3601 expr = convert_nontype_argument_function (type, expr);
3602 if (!expr || expr == error_mark_node)
3605 /* [temp.arg.nontype]/5, bullet 5
3607 For a non-type template-parameter of type reference to function, no
3608 conversions apply. If the template-argument represents a set of
3609 overloaded functions, the matching function is selected from the set
3611 else if (TYPE_REFFN_P (type))
3613 if (TREE_CODE (expr) == ADDR_EXPR)
3615 error ("%qE is not a valid template argument for type %qT "
3616 "because it is a pointer", expr, type);
3617 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3621 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3622 if (!expr || expr == error_mark_node)
3625 expr = build_nop(type, build_address (expr));
3627 /* [temp.arg.nontype]/5, bullet 6
3629 For a non-type template-parameter of type pointer to member function,
3630 no conversions apply. If the template-argument represents a set of
3631 overloaded member functions, the matching member function is selected
3632 from the set (_over.over_). */
3633 else if (TYPE_PTRMEMFUNC_P (type))
3635 expr = instantiate_type (type, expr, tf_none);
3636 if (expr == error_mark_node)
3637 return error_mark_node;
3639 /* There is no way to disable standard conversions in
3640 resolve_address_of_overloaded_function (called by
3641 instantiate_type). It is possible that the call succeeded by
3642 converting &B::I to &D::I (where B is a base of D), so we need
3643 to reject this conversion here.
3645 Actually, even if there was a way to disable standard conversions,
3646 it would still be better to reject them here so that we can
3647 provide a superior diagnostic. */
3648 if (!same_type_p (TREE_TYPE (expr), type))
3650 /* Make sure we are just one standard conversion off. */
3651 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3652 error ("%qE is not a valid template argument for type %qT "
3653 "because it is of type %qT", expr, type,
3655 inform ("standard conversions are not allowed in this context");
3659 /* [temp.arg.nontype]/5, bullet 7
3661 For a non-type template-parameter of type pointer to data member,
3662 qualification conversions (_conv.qual_) are applied. */
3663 else if (TYPE_PTRMEM_P (type))
3665 expr = perform_qualification_conversions (type, expr);
3666 if (expr == error_mark_node)
3669 /* A template non-type parameter must be one of the above. */
3673 /* Sanity check: did we actually convert the argument to the
3675 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3680 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3681 template template parameters. Both PARM_PARMS and ARG_PARMS are
3682 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3685 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3686 the case, then extra parameters must have default arguments.
3688 Consider the example:
3689 template <class T, class Allocator = allocator> class vector;
3690 template<template <class U> class TT> class C;
3692 C<vector> is a valid instantiation. PARM_PARMS for the above code
3693 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3694 T and Allocator) and OUTER_ARGS contains the argument that is used to
3695 substitute the TT parameter. */
3698 coerce_template_template_parms (tree parm_parms,
3700 tsubst_flags_t complain,
3704 int nparms, nargs, i;
3707 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3708 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3710 nparms = TREE_VEC_LENGTH (parm_parms);
3711 nargs = TREE_VEC_LENGTH (arg_parms);
3713 /* The rule here is opposite of coerce_template_parms. */
3716 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3719 for (i = 0; i < nparms; ++i)
3721 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3722 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3724 if (arg == NULL_TREE || arg == error_mark_node
3725 || parm == NULL_TREE || parm == error_mark_node)
3728 if (TREE_CODE (arg) != TREE_CODE (parm))
3731 switch (TREE_CODE (parm))
3737 /* We encounter instantiations of templates like
3738 template <template <template <class> class> class TT>
3741 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3742 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3744 if (!coerce_template_template_parms
3745 (parmparm, argparm, complain, in_decl, outer_args))
3751 /* The tsubst call is used to handle cases such as
3753 template <int> class C {};
3754 template <class T, template <T> class TT> class D {};
3757 i.e. the parameter list of TT depends on earlier parameters. */
3758 if (!dependent_type_p (TREE_TYPE (arg))
3760 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3772 /* Convert the indicated template ARG as necessary to match the
3773 indicated template PARM. Returns the converted ARG, or
3774 error_mark_node if the conversion was unsuccessful. Error and
3775 warning messages are issued under control of COMPLAIN. This
3776 conversion is for the Ith parameter in the parameter list. ARGS is
3777 the full set of template arguments deduced so far. */
3780 convert_template_argument (tree parm,
3783 tsubst_flags_t complain,
3789 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3791 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3793 if (TREE_CODE (arg) == TREE_LIST
3794 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3796 /* The template argument was the name of some
3797 member function. That's usually
3798 invalid, but static members are OK. In any
3799 case, grab the underlying fields/functions
3800 and issue an error later if required. */
3801 arg = TREE_VALUE (arg);
3802 TREE_TYPE (arg) = unknown_type_node;
3805 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3806 requires_type = (TREE_CODE (parm) == TYPE_DECL
3807 || requires_tmpl_type);
3809 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3810 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3811 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3812 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3815 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3816 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3817 arg = TYPE_STUB_DECL (arg);
3819 is_type = TYPE_P (arg) || is_tmpl_type;
3821 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3822 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3824 pedwarn ("to refer to a type member of a template parameter, "
3825 "use %<typename %E%>", arg);
3827 arg = make_typename_type (TREE_OPERAND (arg, 0),
3828 TREE_OPERAND (arg, 1),
3830 complain & tf_error);
3833 if (is_type != requires_type)
3837 if (complain & tf_error)
3839 error ("type/value mismatch at argument %d in template "
3840 "parameter list for %qD",
3843 error (" expected a constant of type %qT, got %qT",
3845 (is_tmpl_type ? DECL_NAME (arg) : arg));
3846 else if (requires_tmpl_type)
3847 error (" expected a class template, got %qE", arg);
3849 error (" expected a type, got %qE", arg);
3852 return error_mark_node;
3854 if (is_tmpl_type ^ requires_tmpl_type)
3856 if (in_decl && (complain & tf_error))
3858 error ("type/value mismatch at argument %d in template "
3859 "parameter list for %qD",
3862 error (" expected a type, got %qT", DECL_NAME (arg));
3864 error (" expected a class template, got %qT", arg);
3866 return error_mark_node;
3871 if (requires_tmpl_type)
3873 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3874 /* The number of argument required is not known yet.
3875 Just accept it for now. */
3876 val = TREE_TYPE (arg);
3879 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3880 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3882 if (coerce_template_template_parms (parmparm, argparm,
3888 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3890 if (val != error_mark_node
3891 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3892 val = TREE_TYPE (val);
3896 if (in_decl && (complain & tf_error))
3898 error ("type/value mismatch at argument %d in "
3899 "template parameter list for %qD",
3901 error (" expected a template of type %qD, got %qD",
3905 val = error_mark_node;
3914 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3916 if (invalid_nontype_parm_type_p (t, complain))
3917 return error_mark_node;
3919 if (!uses_template_parms (arg) && !uses_template_parms (t))
3920 /* We used to call digest_init here. However, digest_init
3921 will report errors, which we don't want when complain
3922 is zero. More importantly, digest_init will try too
3923 hard to convert things: for example, `0' should not be
3924 converted to pointer type at this point according to
3925 the standard. Accepting this is not merely an
3926 extension, since deciding whether or not these
3927 conversions can occur is part of determining which
3928 function template to call, or whether a given explicit
3929 argument specification is valid. */
3930 val = convert_nontype_argument (t, arg);
3934 if (val == NULL_TREE)
3935 val = error_mark_node;
3936 else if (val == error_mark_node && (complain & tf_error))
3937 error ("could not convert template argument %qE to %qT", arg, t);
3943 /* Convert all template arguments to their appropriate types, and
3944 return a vector containing the innermost resulting template
3945 arguments. If any error occurs, return error_mark_node. Error and
3946 warning messages are issued under control of COMPLAIN.
3948 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3949 provided in ARGLIST, or else trailing parameters must have default
3950 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3951 deduction for any unspecified trailing arguments. */
3954 coerce_template_parms (tree parms,
3957 tsubst_flags_t complain,
3958 int require_all_arguments)
3960 int nparms, nargs, i, lost = 0;
3963 tree new_inner_args;
3965 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3966 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3967 nparms = TREE_VEC_LENGTH (parms);
3971 && require_all_arguments
3972 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3974 if (complain & tf_error)
3976 error ("wrong number of template arguments (%d, should be %d)",
3980 cp_error_at ("provided for %qD", in_decl);
3983 return error_mark_node;
3986 new_inner_args = make_tree_vec (nparms);
3987 new_args = add_outermost_template_args (args, new_inner_args);
3988 for (i = 0; i < nparms; i++)
3993 /* Get the Ith template parameter. */
3994 parm = TREE_VEC_ELT (parms, i);
3996 /* Calculate the Ith argument. */
3998 arg = TREE_VEC_ELT (inner_args, i);
3999 else if (require_all_arguments)
4000 /* There must be a default arg in this case. */
4001 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4007 if (arg == error_mark_node)
4009 if (complain & tf_error)
4010 error ("template argument %d is invalid", i + 1);
4013 arg = convert_template_argument (TREE_VALUE (parm),
4014 arg, new_args, complain, i,
4017 if (arg == error_mark_node)
4019 TREE_VEC_ELT (new_inner_args, i) = arg;
4023 return error_mark_node;
4025 return new_inner_args;
4028 /* Returns 1 if template args OT and NT are equivalent. */
4031 template_args_equal (tree ot, tree nt)
4036 if (TREE_CODE (nt) == TREE_VEC)
4037 /* For member templates */
4038 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4039 else if (TYPE_P (nt))
4040 return TYPE_P (ot) && same_type_p (ot, nt);
4041 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4044 return cp_tree_equal (ot, nt);
4047 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4048 of template arguments. Returns 0 otherwise. */
4051 comp_template_args (tree oldargs, tree newargs)
4055 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4058 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4060 tree nt = TREE_VEC_ELT (newargs, i);
4061 tree ot = TREE_VEC_ELT (oldargs, i);
4063 if (! template_args_equal (ot, nt))
4069 /* Given class template name and parameter list, produce a user-friendly name
4070 for the instantiation. */
4073 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4075 static struct obstack scratch_obstack;
4076 static char *scratch_firstobj;
4079 if (!scratch_firstobj)
4080 gcc_obstack_init (&scratch_obstack);
4082 obstack_free (&scratch_obstack, scratch_firstobj);
4083 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4085 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4086 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4090 nparms = TREE_VEC_LENGTH (parms);
4091 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4092 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4093 for (i = 0; i < nparms; i++)
4095 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4096 tree arg = TREE_VEC_ELT (arglist, i);
4101 if (TREE_CODE (parm) == TYPE_DECL)
4103 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4106 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4108 if (TREE_CODE (arg) == TEMPLATE_DECL)
4110 /* Already substituted with real template. Just output
4111 the template name here */
4112 tree context = DECL_CONTEXT (arg);
4115 /* The template may be defined in a namespace, or
4116 may be a member template. */
4117 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4118 || CLASS_TYPE_P (context));
4119 cat (decl_as_string (DECL_CONTEXT (arg),
4120 TFF_PLAIN_IDENTIFIER));
4123 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4126 /* Output the parameter declaration. */
4127 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4131 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4133 /* No need to check arglist against parmlist here; we did that
4134 in coerce_template_parms, called from lookup_template_class. */
4135 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4138 char *bufp = obstack_next_free (&scratch_obstack);
4140 while (bufp[offset - 1] == ' ')
4142 obstack_blank_fast (&scratch_obstack, offset);
4144 /* B<C<char> >, not B<C<char>> */
4145 if (bufp[offset - 1] == '>')
4150 return (char *) obstack_base (&scratch_obstack);
4154 classtype_mangled_name (tree t)
4156 if (CLASSTYPE_TEMPLATE_INFO (t)
4157 /* Specializations have already had their names set up in
4158 lookup_template_class. */
4159 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4161 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4163 /* For non-primary templates, the template parameters are
4164 implicit from their surrounding context. */
4165 if (PRIMARY_TEMPLATE_P (tmpl))
4167 tree name = DECL_NAME (tmpl);
4168 char *mangled_name = mangle_class_name_for_template
4169 (IDENTIFIER_POINTER (name),
4170 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4171 CLASSTYPE_TI_ARGS (t));
4172 tree id = get_identifier (mangled_name);
4173 IDENTIFIER_TEMPLATE (id) = name;
4178 return TYPE_IDENTIFIER (t);
4182 add_pending_template (tree d)
4184 tree ti = (TYPE_P (d)
4185 ? CLASSTYPE_TEMPLATE_INFO (d)
4186 : DECL_TEMPLATE_INFO (d));
4190 if (TI_PENDING_TEMPLATE_FLAG (ti))
4193 /* We are called both from instantiate_decl, where we've already had a
4194 tinst_level pushed, and instantiate_template, where we haven't.
4196 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4199 push_tinst_level (d);
4201 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4202 if (last_pending_template)
4203 TREE_CHAIN (last_pending_template) = pt;
4205 pending_templates = pt;
4207 last_pending_template = pt;
4209 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4216 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4217 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4218 documentation for TEMPLATE_ID_EXPR. */
4221 lookup_template_function (tree fns, tree arglist)
4225 if (fns == error_mark_node || arglist == error_mark_node)
4226 return error_mark_node;
4228 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4229 if (fns == NULL_TREE
4230 || TREE_CODE (fns) == FUNCTION_DECL)
4232 error ("non-template used as template");
4233 return error_mark_node;
4236 gcc_assert (TREE_CODE (fns) == TEMPLATE_DECL
4237 || TREE_CODE (fns) == OVERLOAD
4239 || TREE_CODE (fns) == IDENTIFIER_NODE);
4241 if (BASELINK_P (fns))
4243 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4245 BASELINK_FUNCTIONS (fns),
4250 type = TREE_TYPE (fns);
4251 if (TREE_CODE (fns) == OVERLOAD || !type)
4252 type = unknown_type_node;
4254 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4257 /* Within the scope of a template class S<T>, the name S gets bound
4258 (in build_self_reference) to a TYPE_DECL for the class, not a
4259 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4260 or one of its enclosing classes, and that type is a template,
4261 return the associated TEMPLATE_DECL. Otherwise, the original
4262 DECL is returned. */
4265 maybe_get_template_decl_from_type_decl (tree decl)
4267 return (decl != NULL_TREE
4268 && TREE_CODE (decl) == TYPE_DECL
4269 && DECL_ARTIFICIAL (decl)
4270 && CLASS_TYPE_P (TREE_TYPE (decl))
4271 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4272 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4275 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4276 parameters, find the desired type.
4278 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4280 IN_DECL, if non-NULL, is the template declaration we are trying to
4283 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4284 the class we are looking up.
4286 Issue error and warning messages under control of COMPLAIN.
4288 If the template class is really a local class in a template
4289 function, then the FUNCTION_CONTEXT is the function in which it is
4292 ??? Note that this function is currently called *twice* for each
4293 template-id: the first time from the parser, while creating the
4294 incomplete type (finish_template_type), and the second type during the
4295 real instantiation (instantiate_template_class). This is surely something
4296 that we want to avoid. It also causes some problems with argument
4297 coercion (see convert_nontype_argument for more information on this). */
4300 lookup_template_class (tree d1,
4305 tsubst_flags_t complain)
4307 tree template = NULL_TREE, parmlist;
4310 timevar_push (TV_NAME_LOOKUP);
4312 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4314 tree value = innermost_non_namespace_value (d1);
4315 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4320 push_decl_namespace (context);
4321 template = lookup_name (d1, /*prefer_type=*/0);
4322 template = maybe_get_template_decl_from_type_decl (template);
4324 pop_decl_namespace ();
4327 context = DECL_CONTEXT (template);
4329 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4331 tree type = TREE_TYPE (d1);
4333 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4334 an implicit typename for the second A. Deal with it. */
4335 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4336 type = TREE_TYPE (type);
4338 if (CLASSTYPE_TEMPLATE_INFO (type))
4340 template = CLASSTYPE_TI_TEMPLATE (type);
4341 d1 = DECL_NAME (template);
4344 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4345 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4347 template = TYPE_TI_TEMPLATE (d1);
4348 d1 = DECL_NAME (template);
4350 else if (TREE_CODE (d1) == TEMPLATE_DECL
4351 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4354 d1 = DECL_NAME (template);
4355 context = DECL_CONTEXT (template);
4358 /* Issue an error message if we didn't find a template. */
4361 if (complain & tf_error)
4362 error ("%qT is not a template", d1);
4363 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4366 if (TREE_CODE (template) != TEMPLATE_DECL
4367 /* Make sure it's a user visible template, if it was named by
4369 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4370 && !PRIMARY_TEMPLATE_P (template)))
4372 if (complain & tf_error)
4374 error ("non-template type %qT used as a template", d1);
4376 cp_error_at ("for template declaration %qD", in_decl);
4378 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4381 complain &= ~tf_user;
4383 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4385 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4386 template arguments */
4391 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4393 /* Consider an example where a template template parameter declared as
4395 template <class T, class U = std::allocator<T> > class TT
4397 The template parameter level of T and U are one level larger than
4398 of TT. To proper process the default argument of U, say when an
4399 instantiation `TT<int>' is seen, we need to build the full
4400 arguments containing {int} as the innermost level. Outer levels,
4401 available when not appearing as default template argument, can be
4402 obtained from `current_template_args ()'.
4404 Suppose that TT is later substituted with std::vector. The above
4405 instantiation is `TT<int, std::allocator<T> >' with TT at
4406 level 1, and T at level 2, while the template arguments at level 1
4407 becomes {std::vector} and the inner level 2 is {int}. */
4409 if (current_template_parms)
4410 arglist = add_to_template_args (current_template_args (), arglist);
4412 arglist2 = coerce_template_parms (parmlist, arglist, template,
4413 complain, /*require_all_args=*/1);
4414 if (arglist2 == error_mark_node
4415 || (!uses_template_parms (arglist2)
4416 && check_instantiated_args (template, arglist2, complain)))
4417 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4419 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4420 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4424 tree template_type = TREE_TYPE (template);
4427 tree found = NULL_TREE;
4430 int is_partial_instantiation;
4432 gen_tmpl = most_general_template (template);
4433 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4434 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4435 arg_depth = TMPL_ARGS_DEPTH (arglist);
4437 if (arg_depth == 1 && parm_depth > 1)
4439 /* We've been given an incomplete set of template arguments.
4442 template <class T> struct S1 {
4443 template <class U> struct S2 {};
4444 template <class U> struct S2<U*> {};
4447 we will be called with an ARGLIST of `U*', but the
4448 TEMPLATE will be `template <class T> template
4449 <class U> struct S1<T>::S2'. We must fill in the missing
4452 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4454 arg_depth = TMPL_ARGS_DEPTH (arglist);
4457 /* Now we should have enough arguments. */
4458 gcc_assert (parm_depth == arg_depth);
4460 /* From here on, we're only interested in the most general
4462 template = gen_tmpl;
4464 /* Calculate the BOUND_ARGS. These will be the args that are
4465 actually tsubst'd into the definition to create the
4469 /* We have multiple levels of arguments to coerce, at once. */
4471 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4473 tree bound_args = make_tree_vec (parm_depth);
4475 for (i = saved_depth,
4476 t = DECL_TEMPLATE_PARMS (template);
4477 i > 0 && t != NULL_TREE;
4478 --i, t = TREE_CHAIN (t))
4480 tree a = coerce_template_parms (TREE_VALUE (t),
4482 complain, /*require_all_args=*/1);
4484 /* Don't process further if one of the levels fails. */
4485 if (a == error_mark_node)
4487 /* Restore the ARGLIST to its full size. */
4488 TREE_VEC_LENGTH (arglist) = saved_depth;
4489 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4492 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4494 /* We temporarily reduce the length of the ARGLIST so
4495 that coerce_template_parms will see only the arguments
4496 corresponding to the template parameters it is
4498 TREE_VEC_LENGTH (arglist)--;
4501 /* Restore the ARGLIST to its full size. */
4502 TREE_VEC_LENGTH (arglist) = saved_depth;
4504 arglist = bound_args;
4508 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4509 INNERMOST_TEMPLATE_ARGS (arglist),
4511 complain, /*require_all_args=*/1);
4513 if (arglist == error_mark_node)
4514 /* We were unable to bind the arguments. */
4515 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4517 /* In the scope of a template class, explicit references to the
4518 template class refer to the type of the template, not any
4519 instantiation of it. For example, in:
4521 template <class T> class C { void f(C<T>); }
4523 the `C<T>' is just the same as `C'. Outside of the
4524 class, however, such a reference is an instantiation. */
4525 if (comp_template_args (TYPE_TI_ARGS (template_type),
4528 found = template_type;
4530 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4534 for (ctx = current_class_type;
4535 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4537 ? TYPE_CONTEXT (ctx)
4538 : DECL_CONTEXT (ctx)))
4539 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4542 /* We're not in the scope of the class, so the
4543 TEMPLATE_TYPE is not the type we want after all. */
4549 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4551 /* If we already have this specialization, return it. */
4552 found = retrieve_specialization (template, arglist,
4553 /*class_specializations_p=*/false);
4555 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4557 /* This type is a "partial instantiation" if any of the template
4558 arguments still involve template parameters. Note that we set
4559 IS_PARTIAL_INSTANTIATION for partial specializations as
4561 is_partial_instantiation = uses_template_parms (arglist);
4563 /* If the deduced arguments are invalid, then the binding
4565 if (!is_partial_instantiation
4566 && check_instantiated_args (template,
4567 INNERMOST_TEMPLATE_ARGS (arglist),
4569 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4571 if (!is_partial_instantiation
4572 && !PRIMARY_TEMPLATE_P (template)
4573 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4575 found = xref_tag_from_type (TREE_TYPE (template),
4576 DECL_NAME (template),
4577 /*tag_scope=*/ts_global);
4578 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4581 context = tsubst (DECL_CONTEXT (template), arglist,
4584 context = global_namespace;
4586 /* Create the type. */
4587 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4589 if (!is_partial_instantiation)
4591 set_current_access_from_decl (TYPE_NAME (template_type));
4592 t = start_enum (TYPE_IDENTIFIER (template_type));
4595 /* We don't want to call start_enum for this type, since
4596 the values for the enumeration constants may involve
4597 template parameters. And, no one should be interested
4598 in the enumeration constants for such a type. */
4599 t = make_node (ENUMERAL_TYPE);
4603 t = make_aggr_type (TREE_CODE (template_type));
4604 CLASSTYPE_DECLARED_CLASS (t)
4605 = CLASSTYPE_DECLARED_CLASS (template_type);
4606 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4607 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4609 /* A local class. Make sure the decl gets registered properly. */
4610 if (context == current_function_decl)
4611 pushtag (DECL_NAME (template), t, 0);
4614 /* If we called start_enum or pushtag above, this information
4615 will already be set up. */
4618 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4620 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4621 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4622 TYPE_STUB_DECL (t) = type_decl;
4623 DECL_SOURCE_LOCATION (type_decl)
4624 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4627 type_decl = TYPE_NAME (t);
4629 TREE_PRIVATE (type_decl)
4630 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4631 TREE_PROTECTED (type_decl)
4632 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4634 /* Set up the template information. We have to figure out which
4635 template is the immediate parent if this is a full
4637 if (parm_depth == 1 || is_partial_instantiation
4638 || !PRIMARY_TEMPLATE_P (template))
4639 /* This case is easy; there are no member templates involved. */
4643 /* This is a full instantiation of a member template. Look
4644 for a partial instantiation of which this is an instance. */
4646 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4647 found; found = TREE_CHAIN (found))
4650 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4652 /* We only want partial instantiations, here, not
4653 specializations or full instantiations. */
4654 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4655 || !uses_template_parms (TREE_VALUE (found)))
4658 /* Temporarily reduce by one the number of levels in the
4659 ARGLIST and in FOUND so as to avoid comparing the
4660 last set of arguments. */
4661 TREE_VEC_LENGTH (arglist)--;
4662 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4664 /* See if the arguments match. If they do, then TMPL is
4665 the partial instantiation we want. */
4666 success = comp_template_args (TREE_PURPOSE (found), arglist);
4668 /* Restore the argument vectors to their full size. */
4669 TREE_VEC_LENGTH (arglist)++;
4670 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4681 /* There was no partial instantiation. This happens
4682 where C<T> is a member template of A<T> and it's used
4685 template <typename T> struct B { A<T>::C<int> m; };
4688 Create the partial instantiation.
4690 TREE_VEC_LENGTH (arglist)--;
4691 found = tsubst (template, arglist, complain, NULL_TREE);
4692 TREE_VEC_LENGTH (arglist)++;
4696 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4697 DECL_TEMPLATE_INSTANTIATIONS (template)
4698 = tree_cons (arglist, t,
4699 DECL_TEMPLATE_INSTANTIATIONS (template));
4701 if (TREE_CODE (t) == ENUMERAL_TYPE
4702 && !is_partial_instantiation)
4703 /* Now that the type has been registered on the instantiations
4704 list, we set up the enumerators. Because the enumeration
4705 constants may involve the enumeration type itself, we make
4706 sure to register the type first, and then create the
4707 constants. That way, doing tsubst_expr for the enumeration
4708 constants won't result in recursive calls here; we'll find
4709 the instantiation and exit above. */
4710 tsubst_enum (template_type, t, arglist);
4712 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4714 if (TREE_CODE (t) != ENUMERAL_TYPE)
4715 DECL_NAME (type_decl) = classtype_mangled_name (t);
4716 if (is_partial_instantiation)
4717 /* If the type makes use of template parameters, the
4718 code that generates debugging information will crash. */
4719 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4721 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4723 timevar_pop (TV_NAME_LOOKUP);
4730 struct pointer_set_t *visited;
4733 /* Called from for_each_template_parm via walk_tree. */
4736 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4739 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4740 tree_fn_t fn = pfd->fn;
4741 void *data = pfd->data;
4744 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4745 return error_mark_node;
4747 switch (TREE_CODE (t))
4750 if (TYPE_PTRMEMFUNC_P (t))
4756 if (!TYPE_TEMPLATE_INFO (t))
4758 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4759 fn, data, pfd->visited))
4760 return error_mark_node;
4764 /* Since we're not going to walk subtrees, we have to do this
4766 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4768 return error_mark_node;
4772 /* Check the return type. */
4773 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4774 return error_mark_node;
4776 /* Check the parameter types. Since default arguments are not
4777 instantiated until they are needed, the TYPE_ARG_TYPES may
4778 contain expressions that involve template parameters. But,
4779 no-one should be looking at them yet. And, once they're
4780 instantiated, they don't contain template parameters, so
4781 there's no point in looking at them then, either. */
4785 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4786 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4788 return error_mark_node;
4790 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4791 want walk_tree walking into them itself. */
4797 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4799 return error_mark_node;
4804 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4805 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4807 return error_mark_node;
4812 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4813 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4815 return error_mark_node;
4816 if (DECL_CONTEXT (t)
4817 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4819 return error_mark_node;
4822 case BOUND_TEMPLATE_TEMPLATE_PARM:
4823 /* Record template parameters such as `T' inside `TT<T>'. */
4824 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4825 return error_mark_node;
4828 case TEMPLATE_TEMPLATE_PARM:
4829 case TEMPLATE_TYPE_PARM:
4830 case TEMPLATE_PARM_INDEX:
4831 if (fn && (*fn)(t, data))
4832 return error_mark_node;
4834 return error_mark_node;
4838 /* A template template parameter is encountered. */
4839 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4840 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4841 return error_mark_node;
4843 /* Already substituted template template parameter */
4849 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4850 data, pfd->visited))
4851 return error_mark_node;
4855 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4856 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4857 (TREE_TYPE (t)), fn, data,
4859 return error_mark_node;
4864 /* If there's no type, then this thing must be some expression
4865 involving template parameters. */
4866 if (!fn && !TREE_TYPE (t))
4867 return error_mark_node;
4872 case REINTERPRET_CAST_EXPR:
4873 case CONST_CAST_EXPR:
4874 case STATIC_CAST_EXPR:
4875 case DYNAMIC_CAST_EXPR:
4879 case PSEUDO_DTOR_EXPR:
4881 return error_mark_node;
4885 /* If we do not handle this case specially, we end up walking
4886 the BINFO hierarchy, which is circular, and therefore
4887 confuses walk_tree. */
4889 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4891 return error_mark_node;
4898 /* We didn't find any template parameters we liked. */
4902 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4903 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4904 call FN with the parameter and the DATA.
4905 If FN returns nonzero, the iteration is terminated, and
4906 for_each_template_parm returns 1. Otherwise, the iteration
4907 continues. If FN never returns a nonzero value, the value
4908 returned by for_each_template_parm is 0. If FN is NULL, it is
4909 considered to be the function which always returns 1. */
4912 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4913 struct pointer_set_t *visited)
4915 struct pair_fn_data pfd;
4922 /* Walk the tree. (Conceptually, we would like to walk without
4923 duplicates, but for_each_template_parm_r recursively calls
4924 for_each_template_parm, so we would need to reorganize a fair
4925 bit to use walk_tree_without_duplicates, so we keep our own
4928 pfd.visited = visited;
4930 pfd.visited = pointer_set_create ();
4931 result = walk_tree (&t,
4932 for_each_template_parm_r,
4934 pfd.visited) != NULL_TREE;
4939 pointer_set_destroy (pfd.visited);
4946 /* Returns true if T depends on any template parameter. */
4949 uses_template_parms (tree t)
4952 int saved_processing_template_decl;
4954 saved_processing_template_decl = processing_template_decl;
4955 if (!saved_processing_template_decl)
4956 processing_template_decl = 1;
4958 dependent_p = dependent_type_p (t);
4959 else if (TREE_CODE (t) == TREE_VEC)
4960 dependent_p = any_dependent_template_arguments_p (t);
4961 else if (TREE_CODE (t) == TREE_LIST)
4962 dependent_p = (uses_template_parms (TREE_VALUE (t))
4963 || uses_template_parms (TREE_CHAIN (t)));
4966 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4967 || TREE_CODE (t) == OVERLOAD
4968 || TREE_CODE (t) == BASELINK
4969 || CONSTANT_CLASS_P (t))
4970 dependent_p = (type_dependent_expression_p (t)
4971 || value_dependent_expression_p (t));
4974 gcc_assert (t == error_mark_node);
4975 dependent_p = false;
4978 processing_template_decl = saved_processing_template_decl;
4983 /* Returns true if T depends on any template parameter with level LEVEL. */
4986 uses_template_parms_level (tree t, int level)
4988 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4991 static int tinst_depth;
4992 extern int max_tinst_depth;
4993 #ifdef GATHER_STATISTICS
4996 static int tinst_level_tick;
4997 static int last_template_error_tick;
4999 /* We're starting to instantiate D; record the template instantiation context
5000 for diagnostics and to restore it later. */
5003 push_tinst_level (tree d)
5007 if (tinst_depth >= max_tinst_depth)
5009 /* If the instantiation in question still has unbound template parms,
5010 we don't really care if we can't instantiate it, so just return.
5011 This happens with base instantiation for implicit `typename'. */
5012 if (uses_template_parms (d))
5015 last_template_error_tick = tinst_level_tick;
5016 error ("template instantiation depth exceeds maximum of %d (use "
5017 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5018 max_tinst_depth, d);
5020 print_instantiation_context ();
5025 new = make_tinst_level (d, input_location);
5026 TREE_CHAIN (new) = current_tinst_level;
5027 current_tinst_level = new;
5030 #ifdef GATHER_STATISTICS
5031 if (tinst_depth > depth_reached)
5032 depth_reached = tinst_depth;
5039 /* We're done instantiating this template; return to the instantiation
5043 pop_tinst_level (void)
5045 tree old = current_tinst_level;
5047 /* Restore the filename and line number stashed away when we started
5048 this instantiation. */
5049 input_location = TINST_LOCATION (old);
5050 current_tinst_level = TREE_CHAIN (old);
5055 /* We're instantiating a deferred template; restore the template
5056 instantiation context in which the instantiation was requested, which
5057 is one step out from LEVEL. */
5060 reopen_tinst_level (tree level)
5065 for (t = level; t; t = TREE_CHAIN (t))
5068 current_tinst_level = level;
5072 /* Return the outermost template instantiation context, for use with
5073 -falt-external-templates. */
5076 tinst_for_decl (void)
5078 tree p = current_tinst_level;
5081 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
5086 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5087 vector of template arguments, as for tsubst.
5089 Returns an appropriate tsubst'd friend declaration. */
5092 tsubst_friend_function (tree decl, tree args)
5096 if (TREE_CODE (decl) == FUNCTION_DECL
5097 && DECL_TEMPLATE_INSTANTIATION (decl)
5098 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5099 /* This was a friend declared with an explicit template
5100 argument list, e.g.:
5104 to indicate that f was a template instantiation, not a new
5105 function declaration. Now, we have to figure out what
5106 instantiation of what template. */
5108 tree template_id, arglist, fns;
5111 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5113 /* Friend functions are looked up in the containing namespace scope.
5114 We must enter that scope, to avoid finding member functions of the
5115 current cless with same name. */
5116 push_nested_namespace (ns);
5117 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5118 tf_error | tf_warning, NULL_TREE);
5119 pop_nested_namespace (ns);
5120 arglist = tsubst (DECL_TI_ARGS (decl), args,
5121 tf_error | tf_warning, NULL_TREE);
5122 template_id = lookup_template_function (fns, arglist);
5124 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5125 tmpl = determine_specialization (template_id, new_friend,
5127 /*need_member_template=*/0,
5128 TREE_VEC_LENGTH (args));
5129 return instantiate_template (tmpl, new_args, tf_error);
5132 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5134 /* The NEW_FRIEND will look like an instantiation, to the
5135 compiler, but is not an instantiation from the point of view of
5136 the language. For example, we might have had:
5138 template <class T> struct S {
5139 template <class U> friend void f(T, U);
5142 Then, in S<int>, template <class U> void f(int, U) is not an
5143 instantiation of anything. */
5144 if (new_friend == error_mark_node)
5145 return error_mark_node;
5147 DECL_USE_TEMPLATE (new_friend) = 0;
5148 if (TREE_CODE (decl) == TEMPLATE_DECL)
5150 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5151 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5152 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5155 /* The mangled name for the NEW_FRIEND is incorrect. The function
5156 is not a template instantiation and should not be mangled like
5157 one. Therefore, we forget the mangling here; we'll recompute it
5158 later if we need it. */
5159 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5161 SET_DECL_RTL (new_friend, NULL_RTX);
5162 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5165 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5168 tree new_friend_template_info;
5169 tree new_friend_result_template_info;
5171 int new_friend_is_defn;
5173 /* We must save some information from NEW_FRIEND before calling
5174 duplicate decls since that function will free NEW_FRIEND if
5176 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5177 new_friend_is_defn =
5178 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5179 (template_for_substitution (new_friend)))
5181 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5183 /* This declaration is a `primary' template. */
5184 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5186 new_friend_result_template_info
5187 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5190 new_friend_result_template_info = NULL_TREE;
5192 /* Inside pushdecl_namespace_level, we will push into the
5193 current namespace. However, the friend function should go
5194 into the namespace of the template. */
5195 ns = decl_namespace_context (new_friend);
5196 push_nested_namespace (ns);
5197 old_decl = pushdecl_namespace_level (new_friend);
5198 pop_nested_namespace (ns);
5200 if (old_decl != new_friend)
5202 /* This new friend declaration matched an existing
5203 declaration. For example, given:
5205 template <class T> void f(T);
5206 template <class U> class C {
5207 template <class T> friend void f(T) {}
5210 the friend declaration actually provides the definition
5211 of `f', once C has been instantiated for some type. So,
5212 old_decl will be the out-of-class template declaration,
5213 while new_friend is the in-class definition.
5215 But, if `f' was called before this point, the
5216 instantiation of `f' will have DECL_TI_ARGS corresponding
5217 to `T' but not to `U', references to which might appear
5218 in the definition of `f'. Previously, the most general
5219 template for an instantiation of `f' was the out-of-class
5220 version; now it is the in-class version. Therefore, we
5221 run through all specialization of `f', adding to their
5222 DECL_TI_ARGS appropriately. In particular, they need a
5223 new set of outer arguments, corresponding to the
5224 arguments for this class instantiation.
5226 The same situation can arise with something like this:
5229 template <class T> class C {
5233 when `C<int>' is instantiated. Now, `f(int)' is defined
5236 if (!new_friend_is_defn)
5237 /* On the other hand, if the in-class declaration does
5238 *not* provide a definition, then we don't want to alter
5239 existing definitions. We can just leave everything
5244 /* Overwrite whatever template info was there before, if
5245 any, with the new template information pertaining to
5247 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5249 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5250 reregister_specialization (new_friend,
5251 most_general_template (old_decl),
5256 tree new_friend_args;
5258 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5259 = new_friend_result_template_info;
5261 new_friend_args = TI_ARGS (new_friend_template_info);
5262 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5266 tree spec = TREE_VALUE (t);
5269 = add_outermost_template_args (new_friend_args,
5270 DECL_TI_ARGS (spec));
5273 /* Now, since specializations are always supposed to
5274 hang off of the most general template, we must move
5276 t = most_general_template (old_decl);
5279 DECL_TEMPLATE_SPECIALIZATIONS (t)
5280 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5281 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5282 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5287 /* The information from NEW_FRIEND has been merged into OLD_DECL
5288 by duplicate_decls. */
5289 new_friend = old_decl;
5294 tree context = DECL_CONTEXT (new_friend);
5298 template <class T> class C {
5299 template <class U> friend void C1<U>::f (); // case 1
5300 friend void C2<T>::f (); // case 2
5302 we only need to make sure CONTEXT is a complete type for
5303 case 2. To distinguish between the two cases, we note that
5304 CONTEXT of case 1 remains dependent type after tsubst while
5305 this isn't true for case 2. */
5306 ++processing_template_decl;
5307 dependent_p = dependent_type_p (context);
5308 --processing_template_decl;
5311 && !complete_type_or_else (context, NULL_TREE))
5312 return error_mark_node;
5314 if (COMPLETE_TYPE_P (context))
5316 /* Check to see that the declaration is really present, and,
5317 possibly obtain an improved declaration. */
5318 tree fn = check_classfn (context,
5319 new_friend, NULL_TREE);
5329 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5330 template arguments, as for tsubst.
5332 Returns an appropriate tsubst'd friend type or error_mark_node on
5336 tsubst_friend_class (tree friend_tmpl, tree args)
5342 context = DECL_CONTEXT (friend_tmpl);
5346 if (TREE_CODE (context) == NAMESPACE_DECL)
5347 push_nested_namespace (context);
5349 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5352 /* First, we look for a class template. */
5353 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5355 /* But, if we don't find one, it might be because we're in a
5356 situation like this:
5364 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5365 for `S<int>', not the TEMPLATE_DECL. */
5366 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5368 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5369 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5372 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5374 /* The friend template has already been declared. Just
5375 check to see that the declarations match, and install any new
5376 default parameters. We must tsubst the default parameters,
5377 of course. We only need the innermost template parameters
5378 because that is all that redeclare_class_template will look
5380 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5381 > TMPL_ARGS_DEPTH (args))
5384 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5385 args, tf_error | tf_warning);
5386 redeclare_class_template (TREE_TYPE (tmpl), parms);
5389 friend_type = TREE_TYPE (tmpl);
5393 /* The friend template has not already been declared. In this
5394 case, the instantiation of the template class will cause the
5395 injection of this template into the global scope. */
5396 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5398 /* The new TMPL is not an instantiation of anything, so we
5399 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5400 the new type because that is supposed to be the corresponding
5401 template decl, i.e., TMPL. */
5402 DECL_USE_TEMPLATE (tmpl) = 0;
5403 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5404 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5405 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5406 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5408 /* Inject this template into the global scope. */
5409 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5414 if (TREE_CODE (context) == NAMESPACE_DECL)
5415 pop_nested_namespace (context);
5417 pop_nested_class ();
5423 /* Returns zero if TYPE cannot be completed later due to circularity.
5424 Otherwise returns one. */
5427 can_complete_type_without_circularity (tree type)
5429 if (type == NULL_TREE || type == error_mark_node)
5431 else if (COMPLETE_TYPE_P (type))
5433 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5434 return can_complete_type_without_circularity (TREE_TYPE (type));
5435 else if (CLASS_TYPE_P (type)
5436 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5443 instantiate_class_template (tree type)
5445 tree template, args, pattern, t, member;
5450 if (type == error_mark_node)
5451 return error_mark_node;
5453 if (TYPE_BEING_DEFINED (type)
5454 || COMPLETE_TYPE_P (type)
5455 || dependent_type_p (type))
5458 /* Figure out which template is being instantiated. */
5459 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5460 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5462 /* Figure out which arguments are being used to do the
5464 args = CLASSTYPE_TI_ARGS (type);
5466 /* Determine what specialization of the original template to
5468 t = most_specialized_class (template, args);
5469 if (t == error_mark_node)
5471 const char *str = "candidates are:";
5472 error ("ambiguous class template instantiation for %q#T", type);
5473 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5476 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5478 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5482 TYPE_BEING_DEFINED (type) = 1;
5483 return error_mark_node;
5487 pattern = TREE_TYPE (t);
5489 pattern = TREE_TYPE (template);
5491 /* If the template we're instantiating is incomplete, then clearly
5492 there's nothing we can do. */
5493 if (!COMPLETE_TYPE_P (pattern))
5496 /* If we've recursively instantiated too many templates, stop. */
5497 if (! push_tinst_level (type))
5500 /* Now we're really doing the instantiation. Mark the type as in
5501 the process of being defined. */
5502 TYPE_BEING_DEFINED (type) = 1;
5504 /* We may be in the middle of deferred access check. Disable
5506 push_deferring_access_checks (dk_no_deferred);
5508 push_to_top_level ();
5512 /* This TYPE is actually an instantiation of a partial
5513 specialization. We replace the innermost set of ARGS with
5514 the arguments appropriate for substitution. For example,
5517 template <class T> struct S {};
5518 template <class T> struct S<T*> {};
5520 and supposing that we are instantiating S<int*>, ARGS will
5521 present be {int*} but we need {int}. */
5523 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5526 /* If there were multiple levels in ARGS, replacing the
5527 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5528 want, so we make a copy first. */
5529 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5531 args = copy_node (args);
5532 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5538 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5540 /* Set the input location to the template definition. This is needed
5541 if tsubsting causes an error. */
5542 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (pattern));
5544 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5545 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5546 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5547 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5548 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5549 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5550 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5551 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5552 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5553 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5554 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5555 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5556 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5557 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5558 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5559 if (ANON_AGGR_TYPE_P (pattern))
5560 SET_ANON_AGGR_TYPE_P (type);
5562 pbinfo = TYPE_BINFO (pattern);
5564 /* We should never instantiate a nested class before its enclosing
5565 class; we need to look up the nested class by name before we can
5566 instantiate it, and that lookup should instantiate the enclosing
5568 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5569 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5570 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5572 base_list = NULL_TREE;
5573 if (BINFO_N_BASE_BINFOS (pbinfo))
5576 tree context = TYPE_CONTEXT (type);
5580 /* We must enter the scope containing the type, as that is where
5581 the accessibility of types named in dependent bases are
5583 pop_p = push_scope (context ? context : global_namespace);
5585 /* Substitute into each of the bases to determine the actual
5587 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5590 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5592 /* Substitute to figure out the base class. */
5593 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5594 if (base == error_mark_node)
5597 base_list = tree_cons (access, base, base_list);
5598 if (BINFO_VIRTUAL_P (pbase_binfo))
5599 TREE_TYPE (base_list) = integer_type_node;
5602 /* The list is now in reverse order; correct that. */
5603 base_list = nreverse (base_list);
5606 pop_scope (context ? context : global_namespace);
5608 /* Now call xref_basetypes to set up all the base-class
5610 xref_basetypes (type, base_list);
5613 /* Now that our base classes are set up, enter the scope of the
5614 class, so that name lookups into base classes, etc. will work
5615 correctly. This is precisely analogous to what we do in
5616 begin_class_definition when defining an ordinary non-template
5620 /* Now members are processed in the order of declaration. */
5621 for (member = CLASSTYPE_DECL_LIST (pattern);
5622 member; member = TREE_CHAIN (member))
5624 tree t = TREE_VALUE (member);
5626 if (TREE_PURPOSE (member))
5630 /* Build new CLASSTYPE_NESTED_UTDS. */
5633 tree name = TYPE_IDENTIFIER (tag);
5635 bool class_template_p;
5637 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5638 && TYPE_LANG_SPECIFIC (tag)
5639 && CLASSTYPE_IS_TEMPLATE (tag));
5640 /* If the member is a class template, then -- even after
5641 substitution -- there may be dependent types in the
5642 template argument list for the class. We increment
5643 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5644 that function will assume that no types are dependent
5645 when outside of a template. */
5646 if (class_template_p)
5647 ++processing_template_decl;
5648 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5649 if (class_template_p)
5650 --processing_template_decl;
5651 if (newtag == error_mark_node)
5654 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5656 if (class_template_p)
5657 /* Unfortunately, lookup_template_class sets
5658 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5659 instantiation (i.e., for the type of a member
5660 template class nested within a template class.)
5661 This behavior is required for
5662 maybe_process_partial_specialization to work
5663 correctly, but is not accurate in this case;
5664 the TAG is not an instantiation of anything.
5665 (The corresponding TEMPLATE_DECL is an
5666 instantiation, but the TYPE is not.) */
5667 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5669 /* Now, we call pushtag to put this NEWTAG into the scope of
5670 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5671 pushtag calling push_template_decl. We don't have to do
5672 this for enums because it will already have been done in
5675 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5676 pushtag (name, newtag, /*globalize=*/0);
5679 else if (TREE_CODE (t) == FUNCTION_DECL
5680 || DECL_FUNCTION_TEMPLATE_P (t))
5682 /* Build new TYPE_METHODS. */
5685 if (TREE_CODE (t) == TEMPLATE_DECL)
5686 ++processing_template_decl;
5687 r = tsubst (t, args, tf_error, NULL_TREE);
5688 if (TREE_CODE (t) == TEMPLATE_DECL)
5689 --processing_template_decl;
5690 set_current_access_from_decl (r);
5691 grok_special_member_properties (r);
5692 finish_member_declaration (r);
5696 /* Build new TYPE_FIELDS. */
5698 if (TREE_CODE (t) != CONST_DECL)
5702 /* The the file and line for this declaration, to
5703 assist in error message reporting. Since we
5704 called push_tinst_level above, we don't need to
5706 input_location = DECL_SOURCE_LOCATION (t);
5708 if (TREE_CODE (t) == TEMPLATE_DECL)
5709 ++processing_template_decl;
5710 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5711 if (TREE_CODE (t) == TEMPLATE_DECL)
5712 --processing_template_decl;
5713 if (TREE_CODE (r) == VAR_DECL)
5717 if (DECL_INITIALIZED_IN_CLASS_P (r))
5718 init = tsubst_expr (DECL_INITIAL (t), args,
5719 tf_error | tf_warning, NULL_TREE);
5723 finish_static_data_member_decl
5724 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5726 if (DECL_INITIALIZED_IN_CLASS_P (r))
5727 check_static_variable_definition (r, TREE_TYPE (r));
5729 else if (TREE_CODE (r) == FIELD_DECL)
5731 /* Determine whether R has a valid type and can be
5732 completed later. If R is invalid, then it is
5733 replaced by error_mark_node so that it will not be
5734 added to TYPE_FIELDS. */
5735 tree rtype = TREE_TYPE (r);
5736 if (can_complete_type_without_circularity (rtype))
5737 complete_type (rtype);
5739 if (!COMPLETE_TYPE_P (rtype))
5741 cxx_incomplete_type_error (r, rtype);
5742 r = error_mark_node;
5746 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5747 such a thing will already have been added to the field
5748 list by tsubst_enum in finish_member_declaration in the
5749 CLASSTYPE_NESTED_UTDS case above. */
5750 if (!(TREE_CODE (r) == TYPE_DECL
5751 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5752 && DECL_ARTIFICIAL (r)))
5754 set_current_access_from_decl (r);
5755 finish_member_declaration (r);
5762 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5764 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5766 tree friend_type = t;
5767 bool adjust_processing_template_decl = false;
5769 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5771 friend_type = tsubst_friend_class (friend_type, args);
5772 adjust_processing_template_decl = true;
5774 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5776 friend_type = tsubst (friend_type, args,
5777 tf_error | tf_warning, NULL_TREE);
5778 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5779 friend_type = TREE_TYPE (friend_type);
5780 adjust_processing_template_decl = true;
5782 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5784 friend_type = tsubst (friend_type, args,
5785 tf_error | tf_warning, NULL_TREE);
5786 /* Bump processing_template_decl for correct
5787 dependent_type_p calculation. */
5788 ++processing_template_decl;
5789 if (dependent_type_p (friend_type))
5790 adjust_processing_template_decl = true;
5791 --processing_template_decl;
5793 else if (uses_template_parms (friend_type))
5794 friend_type = tsubst (friend_type, args,
5795 tf_error | tf_warning, NULL_TREE);
5796 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5797 friend_type = friend_type;
5800 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5802 /* The call to xref_tag_from_type does injection for friend
5804 push_nested_namespace (ns);
5806 xref_tag_from_type (friend_type, NULL_TREE,
5807 /*tag_scope=*/ts_global);
5808 pop_nested_namespace (ns);
5811 if (adjust_processing_template_decl)
5812 /* Trick make_friend_class into realizing that the friend
5813 we're adding is a template, not an ordinary class. It's
5814 important that we use make_friend_class since it will
5815 perform some error-checking and output cross-reference
5817 ++processing_template_decl;
5819 if (friend_type != error_mark_node)
5820 make_friend_class (type, friend_type, /*complain=*/false);
5822 if (adjust_processing_template_decl)
5823 --processing_template_decl;
5827 /* Build new DECL_FRIENDLIST. */
5830 /* The the file and line for this declaration, to
5831 assist in error message reporting. Since we
5832 called push_tinst_level above, we don't need to
5834 input_location = DECL_SOURCE_LOCATION (t);
5836 if (TREE_CODE (t) == TEMPLATE_DECL)
5838 ++processing_template_decl;
5839 push_deferring_access_checks (dk_no_check);
5842 r = tsubst_friend_function (t, args);
5843 add_friend (type, r, /*complain=*/false);
5844 if (TREE_CODE (t) == TEMPLATE_DECL)
5846 pop_deferring_access_checks ();
5847 --processing_template_decl;
5853 /* Set the file and line number information to whatever is given for
5854 the class itself. This puts error messages involving generated
5855 implicit functions at a predictable point, and the same point
5856 that would be used for non-template classes. */
5857 typedecl = TYPE_MAIN_DECL (type);
5858 input_location = DECL_SOURCE_LOCATION (typedecl);
5860 unreverse_member_declarations (type);
5861 finish_struct_1 (type);
5862 TYPE_BEING_DEFINED (type) = 0;
5864 /* Now that the class is complete, instantiate default arguments for
5865 any member functions. We don't do this earlier because the
5866 default arguments may reference members of the class. */
5867 if (!PRIMARY_TEMPLATE_P (template))
5868 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5869 if (TREE_CODE (t) == FUNCTION_DECL
5870 /* Implicitly generated member functions will not have template
5871 information; they are not instantiations, but instead are
5872 created "fresh" for each instantiation. */
5873 && DECL_TEMPLATE_INFO (t))
5874 tsubst_default_arguments (t);
5877 pop_from_top_level ();
5878 pop_deferring_access_checks ();
5881 /* The vtable for a template class can be emitted in any translation
5882 unit in which the class is instantiated. When there is no key
5883 method, however, finish_struct_1 will already have added TYPE to
5884 the keyed_classes list. */
5885 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5886 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5892 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5898 else if (TYPE_P (t))
5899 r = tsubst (t, args, complain, in_decl);
5902 r = tsubst_expr (t, args, complain, in_decl);
5904 if (!uses_template_parms (r))
5906 /* Sometimes, one of the args was an expression involving a
5907 template constant parameter, like N - 1. Now that we've
5908 tsubst'd, we might have something like 2 - 1. This will
5909 confuse lookup_template_class, so we do constant folding
5910 here. We have to unset processing_template_decl, to fool
5911 tsubst_copy_and_build() into building an actual tree. */
5913 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5914 as simple as it's going to get, and trying to reprocess
5915 the trees will break. Once tsubst_expr et al DTRT for
5916 non-dependent exprs, this code can go away, as the type
5917 will always be set. */
5920 int saved_processing_template_decl = processing_template_decl;
5921 processing_template_decl = 0;
5922 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5923 tf_error, /*in_decl=*/NULL_TREE,
5924 /*function_p=*/false);
5925 processing_template_decl = saved_processing_template_decl;
5933 /* Substitute ARGS into the vector or list of template arguments T. */
5936 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5938 int len = TREE_VEC_LENGTH (t);
5939 int need_new = 0, i;
5940 tree *elts = alloca (len * sizeof (tree));
5942 for (i = 0; i < len; i++)
5944 tree orig_arg = TREE_VEC_ELT (t, i);
5947 if (TREE_CODE (orig_arg) == TREE_VEC)
5948 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5950 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5952 if (new_arg == error_mark_node)
5953 return error_mark_node;
5956 if (new_arg != orig_arg)
5963 t = make_tree_vec (len);
5964 for (i = 0; i < len; i++)
5965 TREE_VEC_ELT (t, i) = elts[i];
5970 /* Return the result of substituting ARGS into the template parameters
5971 given by PARMS. If there are m levels of ARGS and m + n levels of
5972 PARMS, then the result will contain n levels of PARMS. For
5973 example, if PARMS is `template <class T> template <class U>
5974 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5975 result will be `template <int*, double, class V>'. */
5978 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5983 for (new_parms = &r;
5984 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5985 new_parms = &(TREE_CHAIN (*new_parms)),
5986 parms = TREE_CHAIN (parms))
5989 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5992 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5994 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5995 tree default_value = TREE_PURPOSE (tuple);
5996 tree parm_decl = TREE_VALUE (tuple);
5998 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5999 default_value = tsubst_template_arg (default_value, args,
6000 complain, NULL_TREE);
6002 tuple = build_tree_list (default_value, parm_decl);
6003 TREE_VEC_ELT (new_vec, i) = tuple;
6007 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6008 - TMPL_ARGS_DEPTH (args)),
6009 new_vec, NULL_TREE);
6015 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6016 type T. If T is not an aggregate or enumeration type, it is
6017 handled as if by tsubst. IN_DECL is as for tsubst. If
6018 ENTERING_SCOPE is nonzero, T is the context for a template which
6019 we are presently tsubst'ing. Return the substituted value. */
6022 tsubst_aggr_type (tree t,
6024 tsubst_flags_t complain,
6031 switch (TREE_CODE (t))
6034 if (TYPE_PTRMEMFUNC_P (t))
6035 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6037 /* Else fall through. */
6040 if (TYPE_TEMPLATE_INFO (t))
6046 /* First, determine the context for the type we are looking
6048 context = TYPE_CONTEXT (t);
6050 context = tsubst_aggr_type (context, args, complain,
6051 in_decl, /*entering_scope=*/1);
6053 /* Then, figure out what arguments are appropriate for the
6054 type we are trying to find. For example, given:
6056 template <class T> struct S;
6057 template <class T, class U> void f(T, U) { S<U> su; }
6059 and supposing that we are instantiating f<int, double>,
6060 then our ARGS will be {int, double}, but, when looking up
6061 S we only want {double}. */
6062 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6064 if (argvec == error_mark_node)
6065 return error_mark_node;
6067 r = lookup_template_class (t, argvec, in_decl, context,
6068 entering_scope, complain);
6070 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6073 /* This is not a template type, so there's nothing to do. */
6077 return tsubst (t, args, complain, in_decl);
6081 /* Substitute into the default argument ARG (a default argument for
6082 FN), which has the indicated TYPE. */
6085 tsubst_default_argument (tree fn, tree type, tree arg)
6087 tree saved_class_ptr = NULL_TREE;
6088 tree saved_class_ref = NULL_TREE;
6090 /* This default argument came from a template. Instantiate the
6091 default argument here, not in tsubst. In the case of
6100 we must be careful to do name lookup in the scope of S<T>,
6101 rather than in the current class. */
6102 push_access_scope (fn);
6103 /* The default argument expression should not be considered to be
6104 within the scope of FN. Since push_access_scope sets
6105 current_function_decl, we must explicitly clear it here. */
6106 current_function_decl = NULL_TREE;
6107 /* The "this" pointer is not valid in a default argument. */
6110 saved_class_ptr = current_class_ptr;
6111 cp_function_chain->x_current_class_ptr = NULL_TREE;
6112 saved_class_ref = current_class_ref;
6113 cp_function_chain->x_current_class_ref = NULL_TREE;
6116 push_deferring_access_checks(dk_no_deferred);
6117 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6118 tf_error | tf_warning, NULL_TREE);
6119 pop_deferring_access_checks();
6121 /* Restore the "this" pointer. */
6124 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6125 cp_function_chain->x_current_class_ref = saved_class_ref;
6128 pop_access_scope (fn);
6130 /* Make sure the default argument is reasonable. */
6131 arg = check_default_argument (type, arg);
6136 /* Substitute into all the default arguments for FN. */
6139 tsubst_default_arguments (tree fn)
6144 tmpl_args = DECL_TI_ARGS (fn);
6146 /* If this function is not yet instantiated, we certainly don't need
6147 its default arguments. */
6148 if (uses_template_parms (tmpl_args))
6151 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6153 arg = TREE_CHAIN (arg))
6154 if (TREE_PURPOSE (arg))
6155 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6157 TREE_PURPOSE (arg));
6160 /* Substitute the ARGS into the T, which is a _DECL. Return the
6161 result of the substitution. Issue error and warning messages under
6162 control of COMPLAIN. */
6165 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6167 location_t saved_loc;
6171 /* Set the filename and linenumber to improve error-reporting. */
6172 saved_loc = input_location;
6173 input_location = DECL_SOURCE_LOCATION (t);
6175 switch (TREE_CODE (t))
6179 /* We can get here when processing a member function template,
6180 member class template, and template template parameter of
6181 a template class. */
6182 tree decl = DECL_TEMPLATE_RESULT (t);
6187 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6189 /* Template template parameter is treated here. */
6190 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6191 if (new_type == error_mark_node)
6192 return error_mark_node;
6195 TREE_CHAIN (r) = NULL_TREE;
6196 TREE_TYPE (r) = new_type;
6197 DECL_TEMPLATE_RESULT (r)
6198 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6199 DECL_TEMPLATE_PARMS (r)
6200 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6202 TYPE_NAME (new_type) = r;
6206 /* We might already have an instance of this template.
6207 The ARGS are for the surrounding class type, so the
6208 full args contain the tsubst'd args for the context,
6209 plus the innermost args from the template decl. */
6210 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6211 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6212 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6213 full_args = tsubst_template_args (tmpl_args, args,
6216 /* tsubst_template_args doesn't copy the vector if
6217 nothing changed. But, *something* should have
6219 gcc_assert (full_args != tmpl_args);
6221 spec = retrieve_specialization (t, full_args,
6222 /*class_specializations_p=*/true);
6223 if (spec != NULL_TREE)
6229 /* Make a new template decl. It will be similar to the
6230 original, but will record the current template arguments.
6231 We also create a new function declaration, which is just
6232 like the old one, but points to this new template, rather
6233 than the old one. */
6235 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6236 TREE_CHAIN (r) = NULL_TREE;
6239 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6241 /*entering_scope=*/1);
6242 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6244 if (TREE_CODE (decl) == TYPE_DECL)
6246 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6247 if (new_type == error_mark_node)
6248 return error_mark_node;
6250 TREE_TYPE (r) = new_type;
6251 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6252 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6253 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6257 tree new_decl = tsubst (decl, args, complain, in_decl);
6258 if (new_decl == error_mark_node)
6259 return error_mark_node;
6261 DECL_TEMPLATE_RESULT (r) = new_decl;
6262 DECL_TI_TEMPLATE (new_decl) = r;
6263 TREE_TYPE (r) = TREE_TYPE (new_decl);
6264 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6267 SET_DECL_IMPLICIT_INSTANTIATION (r);
6268 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6269 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6271 /* The template parameters for this new template are all the
6272 template parameters for the old template, except the
6273 outermost level of parameters. */
6274 DECL_TEMPLATE_PARMS (r)
6275 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6278 if (PRIMARY_TEMPLATE_P (t))
6279 DECL_PRIMARY_TEMPLATE (r) = r;
6281 if (TREE_CODE (decl) != TYPE_DECL)
6282 /* Record this non-type partial instantiation. */
6283 register_specialization (r, t,
6284 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6291 tree argvec = NULL_TREE;
6299 /* Nobody should be tsubst'ing into non-template functions. */
6300 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6302 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6307 /* If T is not dependent, just return it. We have to
6308 increment PROCESSING_TEMPLATE_DECL because
6309 value_dependent_expression_p assumes that nothing is
6310 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6311 ++processing_template_decl;
6312 dependent_p = value_dependent_expression_p (t);
6313 --processing_template_decl;
6317 /* Calculate the most general template of which R is a
6318 specialization, and the complete set of arguments used to
6320 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6321 argvec = tsubst_template_args (DECL_TI_ARGS
6322 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6323 args, complain, in_decl);
6325 /* Check to see if we already have this specialization. */
6326 spec = retrieve_specialization (gen_tmpl, argvec,
6327 /*class_specializations_p=*/false);
6335 /* We can see more levels of arguments than parameters if
6336 there was a specialization of a member template, like
6339 template <class T> struct S { template <class U> void f(); }
6340 template <> template <class U> void S<int>::f(U);
6342 Here, we'll be substituting into the specialization,
6343 because that's where we can find the code we actually
6344 want to generate, but we'll have enough arguments for
6345 the most general template.
6347 We also deal with the peculiar case:
6349 template <class T> struct S {
6350 template <class U> friend void f();
6352 template <class U> void f() {}
6354 template void f<double>();
6356 Here, the ARGS for the instantiation of will be {int,
6357 double}. But, we only need as many ARGS as there are
6358 levels of template parameters in CODE_PATTERN. We are
6359 careful not to get fooled into reducing the ARGS in
6362 template <class T> struct S { template <class U> void f(U); }
6363 template <class T> template <> void S<T>::f(int) {}
6365 which we can spot because the pattern will be a
6366 specialization in this case. */
6367 args_depth = TMPL_ARGS_DEPTH (args);
6369 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6370 if (args_depth > parms_depth
6371 && !DECL_TEMPLATE_SPECIALIZATION (t))
6372 args = get_innermost_template_args (args, parms_depth);
6376 /* This special case arises when we have something like this:
6378 template <class T> struct S {
6379 friend void f<int>(int, double);
6382 Here, the DECL_TI_TEMPLATE for the friend declaration
6383 will be an IDENTIFIER_NODE. We are being called from
6384 tsubst_friend_function, and we want only to create a
6385 new decl (R) with appropriate types so that we can call
6386 determine_specialization. */
6387 gen_tmpl = NULL_TREE;
6390 if (DECL_CLASS_SCOPE_P (t))
6392 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6396 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6397 complain, t, /*entering_scope=*/1);
6402 ctx = DECL_CONTEXT (t);
6404 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6405 if (type == error_mark_node)
6406 return error_mark_node;
6408 /* We do NOT check for matching decls pushed separately at this
6409 point, as they may not represent instantiations of this
6410 template, and in any case are considered separate under the
6413 DECL_USE_TEMPLATE (r) = 0;
6414 TREE_TYPE (r) = type;
6415 /* Clear out the mangled name and RTL for the instantiation. */
6416 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6417 SET_DECL_RTL (r, NULL_RTX);
6418 DECL_INITIAL (r) = NULL_TREE;
6419 DECL_CONTEXT (r) = ctx;
6421 if (member && DECL_CONV_FN_P (r))
6422 /* Type-conversion operator. Reconstruct the name, in
6423 case it's the name of one of the template's parameters. */
6424 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6426 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6428 DECL_RESULT (r) = NULL_TREE;
6430 TREE_STATIC (r) = 0;
6431 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6432 DECL_EXTERNAL (r) = 1;
6433 /* If this is an instantiation of a function with internal
6434 linkage, we already know what object file linkage will be
6435 assigned to the instantiation. */
6436 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6437 DECL_DEFER_OUTPUT (r) = 0;
6438 TREE_CHAIN (r) = NULL_TREE;
6439 DECL_PENDING_INLINE_INFO (r) = 0;
6440 DECL_PENDING_INLINE_P (r) = 0;
6441 DECL_SAVED_TREE (r) = NULL_TREE;
6443 if (DECL_CLONED_FUNCTION (r))
6445 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6447 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6448 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6451 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6452 this in the special friend case mentioned above where
6453 GEN_TMPL is NULL. */
6456 DECL_TEMPLATE_INFO (r)
6457 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6458 SET_DECL_IMPLICIT_INSTANTIATION (r);
6459 register_specialization (r, gen_tmpl, argvec);
6461 /* We're not supposed to instantiate default arguments
6462 until they are called, for a template. But, for a
6465 template <class T> void f ()
6466 { extern void g(int i = T()); }
6468 we should do the substitution when the template is
6469 instantiated. We handle the member function case in
6470 instantiate_class_template since the default arguments
6471 might refer to other members of the class. */
6473 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6474 && !uses_template_parms (argvec))
6475 tsubst_default_arguments (r);
6478 /* Copy the list of befriending classes. */
6479 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6481 friends = &TREE_CHAIN (*friends))
6483 *friends = copy_node (*friends);
6484 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6489 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6491 maybe_retrofit_in_chrg (r);
6492 if (DECL_CONSTRUCTOR_P (r))
6493 grok_ctor_properties (ctx, r);
6494 /* If this is an instantiation of a member template, clone it.
6495 If it isn't, that'll be handled by
6496 clone_constructors_and_destructors. */
6497 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6498 clone_function_decl (r, /*update_method_vec_p=*/0);
6500 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6501 grok_op_properties (r, DECL_FRIEND_P (r),
6502 (complain & tf_error) != 0);
6504 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6505 SET_DECL_FRIEND_CONTEXT (r,
6506 tsubst (DECL_FRIEND_CONTEXT (t),
6507 args, complain, in_decl));
6516 if (DECL_TEMPLATE_PARM_P (t))
6517 SET_DECL_TEMPLATE_PARM_P (r);
6519 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6520 TREE_TYPE (r) = type;
6521 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6523 if (DECL_INITIAL (r))
6525 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6526 DECL_INITIAL (r) = TREE_TYPE (r);
6528 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6532 DECL_CONTEXT (r) = NULL_TREE;
6534 if (!DECL_TEMPLATE_PARM_P (r))
6535 DECL_ARG_TYPE (r) = type_passed_as (type);
6537 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6538 complain, TREE_CHAIN (t));
6547 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6548 if (type == error_mark_node)
6549 return error_mark_node;
6550 TREE_TYPE (r) = type;
6551 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6553 /* We don't have to set DECL_CONTEXT here; it is set by
6554 finish_member_declaration. */
6555 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6557 TREE_CHAIN (r) = NULL_TREE;
6558 if (VOID_TYPE_P (type))
6559 cp_error_at ("instantiation of %qD as type %qT", r, type);
6566 /* It is not a dependent using decl any more. */
6567 TREE_TYPE (r) = void_type_node;
6569 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6571 = tsubst_copy (DECL_NAME (t), args, complain, in_decl);
6572 TREE_CHAIN (r) = NULL_TREE;
6579 tree argvec = NULL_TREE;
6580 tree gen_tmpl = NULL_TREE;
6582 tree tmpl = NULL_TREE;
6584 tree type = NULL_TREE;
6587 if (TREE_CODE (t) == TYPE_DECL)
6589 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6590 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6591 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6593 /* If this is the canonical decl, we don't have to
6594 mess with instantiations, and often we can't (for
6595 typename, template type parms and such). Note that
6596 TYPE_NAME is not correct for the above test if
6597 we've copied the type for a typedef. */
6598 r = TYPE_NAME (type);
6603 /* Assume this is a non-local variable. */
6606 if (TYPE_P (CP_DECL_CONTEXT (t)))
6607 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6609 in_decl, /*entering_scope=*/1);
6610 else if (DECL_NAMESPACE_SCOPE_P (t))
6611 ctx = DECL_CONTEXT (t);
6614 /* Subsequent calls to pushdecl will fill this in. */
6619 /* Check to see if we already have this specialization. */
6622 tmpl = DECL_TI_TEMPLATE (t);
6623 gen_tmpl = most_general_template (tmpl);
6624 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6625 spec = retrieve_specialization (gen_tmpl, argvec,
6626 /*class_specializations_p=*/false);
6629 spec = retrieve_local_specialization (t);
6638 if (TREE_CODE (r) == VAR_DECL)
6640 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6641 if (type == error_mark_node)
6642 return error_mark_node;
6643 type = complete_type (type);
6644 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6645 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6646 type = check_var_type (DECL_NAME (r), type);
6648 else if (DECL_SELF_REFERENCE_P (t))
6649 SET_DECL_SELF_REFERENCE_P (r);
6650 TREE_TYPE (r) = type;
6651 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6652 DECL_CONTEXT (r) = ctx;
6653 /* Clear out the mangled name and RTL for the instantiation. */
6654 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6655 SET_DECL_RTL (r, NULL_RTX);
6657 /* Don't try to expand the initializer until someone tries to use
6658 this variable; otherwise we run into circular dependencies. */
6659 DECL_INITIAL (r) = NULL_TREE;
6660 SET_DECL_RTL (r, NULL_RTX);
6661 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6663 /* Even if the original location is out of scope, the newly
6664 substituted one is not. */
6665 if (TREE_CODE (r) == VAR_DECL)
6667 DECL_DEAD_FOR_LOCAL (r) = 0;
6668 DECL_INITIALIZED_P (r) = 0;
6673 /* A static data member declaration is always marked
6674 external when it is declared in-class, even if an
6675 initializer is present. We mimic the non-template
6677 DECL_EXTERNAL (r) = 1;
6679 register_specialization (r, gen_tmpl, argvec);
6680 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6681 SET_DECL_IMPLICIT_INSTANTIATION (r);
6684 register_local_specialization (r, t);
6686 TREE_CHAIN (r) = NULL_TREE;
6695 /* Restore the file and line information. */
6696 input_location = saved_loc;
6701 /* Substitute into the ARG_TYPES of a function type. */
6704 tsubst_arg_types (tree arg_types,
6706 tsubst_flags_t complain,
6709 tree remaining_arg_types;
6712 if (!arg_types || arg_types == void_list_node)
6715 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6716 args, complain, in_decl);
6717 if (remaining_arg_types == error_mark_node)
6718 return error_mark_node;
6720 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6721 if (type == error_mark_node)
6722 return error_mark_node;
6723 if (VOID_TYPE_P (type))
6725 if (complain & tf_error)
6727 error ("invalid parameter type %qT", type);
6729 cp_error_at ("in declaration %qD", in_decl);
6731 return error_mark_node;
6734 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6735 top-level qualifiers as required. */
6736 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6738 /* Note that we do not substitute into default arguments here. The
6739 standard mandates that they be instantiated only when needed,
6740 which is done in build_over_call. */
6741 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6742 remaining_arg_types);
6746 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6747 *not* handle the exception-specification for FNTYPE, because the
6748 initial substitution of explicitly provided template parameters
6749 during argument deduction forbids substitution into the
6750 exception-specification:
6754 All references in the function type of the function template to the
6755 corresponding template parameters are replaced by the specified tem-
6756 plate argument values. If a substitution in a template parameter or
6757 in the function type of the function template results in an invalid
6758 type, type deduction fails. [Note: The equivalent substitution in
6759 exception specifications is done only when the function is instanti-
6760 ated, at which point a program is ill-formed if the substitution
6761 results in an invalid type.] */
6764 tsubst_function_type (tree t,
6766 tsubst_flags_t complain,
6773 /* The TYPE_CONTEXT is not used for function/method types. */
6774 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6776 /* Substitute the return type. */
6777 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6778 if (return_type == error_mark_node)
6779 return error_mark_node;
6780 /* The standard does not presently indicate that creation of a
6781 function type with an invalid return type is a deduction failure.
6782 However, that is clearly analogous to creating an array of "void"
6783 or a reference to a reference. This is core issue #486. */
6784 if (TREE_CODE (return_type) == ARRAY_TYPE
6785 || TREE_CODE (return_type) == FUNCTION_TYPE)
6787 if (complain & tf_error)
6789 if (TREE_CODE (return_type) == ARRAY_TYPE)
6790 error ("function returning an array");
6792 error ("function returning a function");
6794 return error_mark_node;
6797 /* Substitute the argument types. */
6798 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6800 if (arg_types == error_mark_node)
6801 return error_mark_node;
6803 /* Construct a new type node and return it. */
6804 if (TREE_CODE (t) == FUNCTION_TYPE)
6805 fntype = build_function_type (return_type, arg_types);
6808 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6809 if (! IS_AGGR_TYPE (r))
6813 Type deduction may fail for any of the following
6816 -- Attempting to create "pointer to member of T" when T
6817 is not a class type. */
6818 if (complain & tf_error)
6819 error ("creating pointer to member function of non-class type %qT",
6821 return error_mark_node;
6824 fntype = build_method_type_directly (r, return_type,
6825 TREE_CHAIN (arg_types));
6827 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6828 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6833 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6834 ARGS into that specification, and return the substituted
6835 specification. If there is no specification, return NULL_TREE. */
6838 tsubst_exception_specification (tree fntype,
6840 tsubst_flags_t complain,
6846 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6847 new_specs = NULL_TREE;
6850 if (! TREE_VALUE (specs))
6856 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6857 if (spec == error_mark_node)
6859 new_specs = add_exception_specifier (new_specs, spec, complain);
6860 specs = TREE_CHAIN (specs);
6866 /* Substitute into the PARMS of a call-declarator. */
6869 tsubst_call_declarator_parms (tree parms,
6871 tsubst_flags_t complain,
6878 if (!parms || parms == void_list_node)
6881 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6882 args, complain, in_decl);
6884 /* Figure out the type of this parameter. */
6885 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6887 /* Figure out the default argument as well. Note that we use
6888 tsubst_expr since the default argument is really an expression. */
6889 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6891 /* Chain this parameter on to the front of those we have already
6892 processed. We don't use hash_tree_cons because that function
6893 doesn't check TREE_PARMLIST. */
6894 new_parms = tree_cons (defarg, type, new_parms);
6899 /* Take the tree structure T and replace template parameters used
6900 therein with the argument vector ARGS. IN_DECL is an associated
6901 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6902 Issue error and warning messages under control of COMPLAIN. Note
6903 that we must be relatively non-tolerant of extensions here, in
6904 order to preserve conformance; if we allow substitutions that
6905 should not be allowed, we may allow argument deductions that should
6906 not succeed, and therefore report ambiguous overload situations
6907 where there are none. In theory, we could allow the substitution,
6908 but indicate that it should have failed, and allow our caller to
6909 make sure that the right thing happens, but we don't try to do this
6912 This function is used for dealing with types, decls and the like;
6913 for expressions, use tsubst_expr or tsubst_copy. */
6916 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6920 if (t == NULL_TREE || t == error_mark_node
6921 || t == integer_type_node
6922 || t == void_type_node
6923 || t == char_type_node
6924 || t == unknown_type_node
6925 || TREE_CODE (t) == NAMESPACE_DECL)
6929 return tsubst_decl (t, args, complain);
6931 if (TREE_CODE (t) == IDENTIFIER_NODE)
6932 type = IDENTIFIER_TYPE_VALUE (t);
6934 type = TREE_TYPE (t);
6936 gcc_assert (type != unknown_type_node);
6939 && TREE_CODE (t) != TYPENAME_TYPE
6940 && TREE_CODE (t) != IDENTIFIER_NODE
6941 && TREE_CODE (t) != FUNCTION_TYPE
6942 && TREE_CODE (t) != METHOD_TYPE)
6943 type = tsubst (type, args, complain, in_decl);
6944 if (type == error_mark_node)
6945 return error_mark_node;
6947 switch (TREE_CODE (t))
6952 return tsubst_aggr_type (t, args, complain, in_decl,
6953 /*entering_scope=*/0);
6956 case IDENTIFIER_NODE:
6968 if (t == integer_type_node)
6971 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6972 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6976 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6978 /* The array dimension behaves like a non-type template arg,
6979 in that we want to fold it as much as possible. */
6980 max = tsubst_template_arg (omax, args, complain, in_decl);
6981 if (!processing_template_decl)
6982 max = integral_constant_value (max);
6984 if (integer_zerop (omax))
6986 /* Still allow an explicit array of size zero. */
6988 pedwarn ("creating array with size zero");
6990 else if (integer_zerop (max)
6991 || (TREE_CODE (max) == INTEGER_CST
6992 && INT_CST_LT (max, integer_zero_node)))
6996 Type deduction may fail for any of the following
6999 Attempting to create an array with a size that is
7000 zero or negative. */
7001 if (complain & tf_error)
7002 error ("creating array with size zero (%qE)", max);
7004 return error_mark_node;
7007 return compute_array_index_type (NULL_TREE, max);
7010 case TEMPLATE_TYPE_PARM:
7011 case TEMPLATE_TEMPLATE_PARM:
7012 case BOUND_TEMPLATE_TEMPLATE_PARM:
7013 case TEMPLATE_PARM_INDEX:
7018 tree arg = NULL_TREE;
7022 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7023 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7024 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7025 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7027 idx = TEMPLATE_TYPE_IDX (t);
7028 level = TEMPLATE_TYPE_LEVEL (t);
7032 idx = TEMPLATE_PARM_IDX (t);
7033 level = TEMPLATE_PARM_LEVEL (t);
7036 levels = TMPL_ARGS_DEPTH (args);
7037 if (level <= levels)
7038 arg = TMPL_ARG (args, level, idx);
7040 if (arg == error_mark_node)
7041 return error_mark_node;
7042 else if (arg != NULL_TREE)
7044 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7046 gcc_assert (TYPE_P (arg));
7047 return cp_build_qualified_type_real
7048 (arg, cp_type_quals (arg) | cp_type_quals (t),
7049 complain | tf_ignore_bad_quals);
7051 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7053 /* We are processing a type constructed from a
7054 template template parameter. */
7055 tree argvec = tsubst (TYPE_TI_ARGS (t),
7056 args, complain, in_decl);
7057 if (argvec == error_mark_node)
7058 return error_mark_node;
7060 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7061 are resolving nested-types in the signature of a
7062 member function templates. Otherwise ARG is a
7063 TEMPLATE_DECL and is the real template to be
7065 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7066 arg = TYPE_NAME (arg);
7068 r = lookup_template_class (arg,
7071 /*entering_scope=*/0,
7073 return cp_build_qualified_type_real
7074 (r, TYPE_QUALS (t), complain);
7077 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7082 /* This can happen during the attempted tsubst'ing in
7083 unify. This means that we don't yet have any information
7084 about the template parameter in question. */
7087 /* If we get here, we must have been looking at a parm for a
7088 more deeply nested template. Make a new version of this
7089 template parameter, but with a lower level. */
7090 switch (TREE_CODE (t))
7092 case TEMPLATE_TYPE_PARM:
7093 case TEMPLATE_TEMPLATE_PARM:
7094 case BOUND_TEMPLATE_TEMPLATE_PARM:
7095 if (cp_type_quals (t))
7097 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7098 r = cp_build_qualified_type_real
7099 (r, cp_type_quals (t),
7100 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7101 ? tf_ignore_bad_quals : 0));
7106 TEMPLATE_TYPE_PARM_INDEX (r)
7107 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7109 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7110 TYPE_MAIN_VARIANT (r) = r;
7111 TYPE_POINTER_TO (r) = NULL_TREE;
7112 TYPE_REFERENCE_TO (r) = NULL_TREE;
7114 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7116 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7118 if (argvec == error_mark_node)
7119 return error_mark_node;
7121 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7122 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7127 case TEMPLATE_PARM_INDEX:
7128 r = reduce_template_parm_level (t, type, levels);
7140 tree purpose, value, chain;
7142 if (t == void_list_node)
7145 purpose = TREE_PURPOSE (t);
7148 purpose = tsubst (purpose, args, complain, in_decl);
7149 if (purpose == error_mark_node)
7150 return error_mark_node;
7152 value = TREE_VALUE (t);
7155 value = tsubst (value, args, complain, in_decl);
7156 if (value == error_mark_node)
7157 return error_mark_node;
7159 chain = TREE_CHAIN (t);
7160 if (chain && chain != void_type_node)
7162 chain = tsubst (chain, args, complain, in_decl);
7163 if (chain == error_mark_node)
7164 return error_mark_node;
7166 if (purpose == TREE_PURPOSE (t)
7167 && value == TREE_VALUE (t)
7168 && chain == TREE_CHAIN (t))
7170 return hash_tree_cons (purpose, value, chain);
7174 /* We should never be tsubsting a binfo. */
7178 /* A vector of template arguments. */
7180 return tsubst_template_args (t, args, complain, in_decl);
7183 case REFERENCE_TYPE:
7185 enum tree_code code;
7187 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7190 code = TREE_CODE (t);
7195 Type deduction may fail for any of the following
7198 -- Attempting to create a pointer to reference type.
7199 -- Attempting to create a reference to a reference type or
7200 a reference to void. */
7201 if (TREE_CODE (type) == REFERENCE_TYPE
7202 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7204 static location_t last_loc;
7206 /* We keep track of the last time we issued this error
7207 message to avoid spewing a ton of messages during a
7208 single bad template instantiation. */
7209 if (complain & tf_error
7210 #ifdef USE_MAPPED_LOCATION
7211 && last_loc != input_location
7213 && (last_loc.line != input_line
7214 || last_loc.file != input_filename)
7218 if (TREE_CODE (type) == VOID_TYPE)
7219 error ("forming reference to void");
7221 error ("forming %s to reference type %qT",
7222 (code == POINTER_TYPE) ? "pointer" : "reference",
7224 last_loc = input_location;
7227 return error_mark_node;
7229 else if (code == POINTER_TYPE)
7231 r = build_pointer_type (type);
7232 if (TREE_CODE (type) == METHOD_TYPE)
7233 r = build_ptrmemfunc_type (r);
7236 r = build_reference_type (type);
7237 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7239 if (r != error_mark_node)
7240 /* Will this ever be needed for TYPE_..._TO values? */
7247 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7248 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7252 Type deduction may fail for any of the following
7255 -- Attempting to create "pointer to member of T" when T
7256 is not a class type. */
7257 if (complain & tf_error)
7258 error ("creating pointer to member of non-class type %qT", r);
7259 return error_mark_node;
7261 if (TREE_CODE (type) == REFERENCE_TYPE)
7263 if (complain & tf_error)
7264 error ("creating pointer to member reference type %qT", type);
7266 return error_mark_node;
7268 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7269 if (TREE_CODE (type) == FUNCTION_TYPE)
7271 /* This is really a method type. The cv qualifiers of the
7272 this pointer should _not_ be determined by the cv
7273 qualifiers of the class type. They should be held
7274 somewhere in the FUNCTION_TYPE, but we don't do that at
7275 the moment. Consider
7276 typedef void (Func) () const;
7278 template <typename T1> void Foo (Func T1::*);
7283 method_type = build_method_type_directly (TYPE_MAIN_VARIANT (r),
7285 TYPE_ARG_TYPES (type));
7286 return build_ptrmemfunc_type (build_pointer_type (method_type));
7289 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7298 fntype = tsubst_function_type (t, args, complain, in_decl);
7299 if (fntype == error_mark_node)
7300 return error_mark_node;
7302 /* Substitute the exception specification. */
7303 specs = tsubst_exception_specification (t, args, complain,
7306 fntype = build_exception_variant (fntype, specs);
7311 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7312 if (domain == error_mark_node)
7313 return error_mark_node;
7315 /* As an optimization, we avoid regenerating the array type if
7316 it will obviously be the same as T. */
7317 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7320 /* These checks should match the ones in grokdeclarator.
7324 The deduction may fail for any of the following reasons:
7326 -- Attempting to create an array with an element type that
7327 is void, a function type, or a reference type, or [DR337]
7328 an abstract class type. */
7329 if (TREE_CODE (type) == VOID_TYPE
7330 || TREE_CODE (type) == FUNCTION_TYPE
7331 || TREE_CODE (type) == REFERENCE_TYPE)
7333 if (complain & tf_error)
7334 error ("creating array of %qT", type);
7335 return error_mark_node;
7337 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7339 if (complain & tf_error)
7340 error ("creating array of %qT, which is an abstract class type",
7342 return error_mark_node;
7345 r = build_cplus_array_type (type, domain);
7352 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7353 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7355 if (e1 == error_mark_node || e2 == error_mark_node)
7356 return error_mark_node;
7358 return fold (build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2));
7364 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7365 if (e == error_mark_node)
7366 return error_mark_node;
7368 return fold (build1 (TREE_CODE (t), TREE_TYPE (t), e));
7373 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7374 in_decl, /*entering_scope=*/1);
7375 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7378 if (ctx == error_mark_node || f == error_mark_node)
7379 return error_mark_node;
7381 if (!IS_AGGR_TYPE (ctx))
7383 if (complain & tf_error)
7384 error ("%qT is not a class, struct, or union type", ctx);
7385 return error_mark_node;
7387 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7389 /* Normally, make_typename_type does not require that the CTX
7390 have complete type in order to allow things like:
7392 template <class T> struct S { typename S<T>::X Y; };
7394 But, such constructs have already been resolved by this
7395 point, so here CTX really should have complete type, unless
7396 it's a partial instantiation. */
7397 ctx = complete_type (ctx);
7398 if (!COMPLETE_TYPE_P (ctx))
7400 if (complain & tf_error)
7401 cxx_incomplete_type_error (NULL_TREE, ctx);
7402 return error_mark_node;
7406 f = make_typename_type (ctx, f, typename_type,
7407 (complain & tf_error) | tf_keep_type_decl);
7408 if (f == error_mark_node)
7410 if (TREE_CODE (f) == TYPE_DECL)
7412 complain |= tf_ignore_bad_quals;
7416 if (TREE_CODE (f) != TYPENAME_TYPE)
7418 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7419 error ("%qT resolves to %qT, which is not an enumeration type",
7421 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7422 error ("%qT resolves to %qT, which is is not a class type",
7426 return cp_build_qualified_type_real
7427 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7430 case UNBOUND_CLASS_TEMPLATE:
7432 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7433 in_decl, /*entering_scope=*/1);
7434 tree name = TYPE_IDENTIFIER (t);
7435 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7437 if (ctx == error_mark_node || name == error_mark_node)
7438 return error_mark_node;
7441 parm_list = tsubst_template_parms (parm_list, args, complain);
7442 return make_unbound_class_template (ctx, name, parm_list, complain);
7452 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7453 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7454 if (e1 == error_mark_node || e2 == error_mark_node)
7455 return error_mark_node;
7457 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7462 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7463 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7464 if (e1 == error_mark_node || e2 == error_mark_node)
7465 return error_mark_node;
7467 return build_nt (TREE_CODE (t), e1, e2);
7474 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7475 complain, in_decl));
7476 return cp_build_qualified_type_real (type,
7478 | cp_type_quals (type),
7483 sorry ("use of %qs in template",
7484 tree_code_name [(int) TREE_CODE (t)]);
7485 return error_mark_node;
7489 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7490 type of the expression on the left-hand side of the "." or "->"
7494 tsubst_baselink (tree baselink, tree object_type,
7495 tree args, tsubst_flags_t complain, tree in_decl)
7498 tree qualifying_scope;
7500 tree template_args = 0;
7501 bool template_id_p = false;
7503 /* A baselink indicates a function from a base class. The
7504 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7505 non-dependent types; otherwise, the lookup could not have
7506 succeeded. However, they may indicate bases of the template
7507 class, rather than the instantiated class.
7509 In addition, lookups that were not ambiguous before may be
7510 ambiguous now. Therefore, we perform the lookup again. */
7511 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7512 fns = BASELINK_FUNCTIONS (baselink);
7513 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7515 template_id_p = true;
7516 template_args = TREE_OPERAND (fns, 1);
7517 fns = TREE_OPERAND (fns, 0);
7519 template_args = tsubst_template_args (template_args, args,
7522 name = DECL_NAME (get_first_fn (fns));
7523 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7525 /* If lookup found a single function, mark it as used at this
7526 point. (If it lookup found multiple functions the one selected
7527 later by overload resolution will be marked as used at that
7529 if (BASELINK_P (baselink))
7530 fns = BASELINK_FUNCTIONS (baselink);
7531 if (!template_id_p && !really_overloaded_fn (fns))
7532 mark_used (OVL_CURRENT (fns));
7534 /* Add back the template arguments, if present. */
7535 if (BASELINK_P (baselink) && template_id_p)
7536 BASELINK_FUNCTIONS (baselink)
7537 = build_nt (TEMPLATE_ID_EXPR,
7538 BASELINK_FUNCTIONS (baselink),
7542 object_type = current_class_type;
7543 return adjust_result_of_qualified_name_lookup (baselink,
7548 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7549 true if the qualified-id will be a postfix-expression in-and-of
7550 itself; false if more of the postfix-expression follows the
7551 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7555 tsubst_qualified_id (tree qualified_id, tree args,
7556 tsubst_flags_t complain, tree in_decl,
7557 bool done, bool address_p)
7565 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7567 /* Figure out what name to look up. */
7568 name = TREE_OPERAND (qualified_id, 1);
7569 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7572 template_args = TREE_OPERAND (name, 1);
7574 template_args = tsubst_template_args (template_args, args,
7576 name = TREE_OPERAND (name, 0);
7580 is_template = false;
7581 template_args = NULL_TREE;
7584 /* Substitute into the qualifying scope. When there are no ARGS, we
7585 are just trying to simplify a non-dependent expression. In that
7586 case the qualifying scope may be dependent, and, in any case,
7587 substituting will not help. */
7588 scope = TREE_OPERAND (qualified_id, 0);
7591 scope = tsubst (scope, args, complain, in_decl);
7592 expr = tsubst_copy (name, args, complain, in_decl);
7597 if (dependent_type_p (scope))
7598 return build_nt (SCOPE_REF, scope, expr);
7600 if (!BASELINK_P (name) && !DECL_P (expr))
7602 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7603 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7604 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7606 if (complain & tf_error)
7608 error ("dependent-name %qE is parsed as a non-type, but "
7609 "instantiation yields a type", qualified_id);
7610 inform ("say %<typename %E%> if a type is meant", qualified_id);
7612 return error_mark_node;
7618 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7620 /* Remember that there was a reference to this entity. */
7624 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7626 if (complain & tf_error)
7627 qualified_name_lookup_error (scope,
7628 TREE_OPERAND (qualified_id, 1),
7630 return error_mark_node;
7634 expr = lookup_template_function (expr, template_args);
7636 if (expr == error_mark_node && complain & tf_error)
7637 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7639 else if (TYPE_P (scope))
7641 expr = (adjust_result_of_qualified_name_lookup
7642 (expr, scope, current_class_type));
7643 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7649 /* Like tsubst, but deals with expressions. This function just replaces
7650 template parms; to finish processing the resultant expression, use
7654 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7656 enum tree_code code;
7659 if (t == NULL_TREE || t == error_mark_node)
7662 code = TREE_CODE (t);
7667 r = retrieve_local_specialization (t);
7668 gcc_assert (r != NULL);
7677 if (DECL_TEMPLATE_PARM_P (t))
7678 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7679 /* There is no need to substitute into namespace-scope
7681 if (DECL_NAMESPACE_SCOPE_P (t))
7683 /* If ARGS is NULL, then T is known to be non-dependent. */
7684 if (args == NULL_TREE)
7685 return integral_constant_value (t);
7687 /* Unfortunately, we cannot just call lookup_name here.
7690 template <int I> int f() {
7692 struct S { void g() { E e = a; } };
7695 When we instantiate f<7>::S::g(), say, lookup_name is not
7696 clever enough to find f<7>::a. */
7698 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7699 /*entering_scope=*/0);
7701 for (v = TYPE_VALUES (enum_type);
7704 if (TREE_PURPOSE (v) == DECL_NAME (t))
7705 return TREE_VALUE (v);
7707 /* We didn't find the name. That should never happen; if
7708 name-lookup found it during preliminary parsing, we
7709 should find it again here during instantiation. */
7715 if (DECL_CONTEXT (t))
7719 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7720 /*entering_scope=*/1);
7721 if (ctx != DECL_CONTEXT (t))
7723 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7726 if (complain & tf_error)
7727 error ("using invalid field %qD", t);
7728 return error_mark_node;
7738 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7739 || local_variable_p (t))
7740 t = tsubst (t, args, complain, in_decl);
7745 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7748 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7749 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7750 args, complain, in_decl);
7751 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7752 return tsubst (t, args, complain, in_decl);
7753 else if (DECL_CLASS_SCOPE_P (t)
7754 && uses_template_parms (DECL_CONTEXT (t)))
7756 /* Template template argument like the following example need
7759 template <template <class> class TT> struct C {};
7760 template <class T> struct D {
7761 template <class U> struct E {};
7766 We are processing the template argument `E' in #1 for
7767 the template instantiation #2. Originally, `E' is a
7768 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7769 have to substitute this with one having context `D<int>'. */
7771 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7772 return lookup_field (context, DECL_NAME(t), 0, false);
7775 /* Ordinary template template argument. */
7779 case REINTERPRET_CAST_EXPR:
7780 case CONST_CAST_EXPR:
7781 case STATIC_CAST_EXPR:
7782 case DYNAMIC_CAST_EXPR:
7785 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7786 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7790 case TRUTH_NOT_EXPR:
7793 case CONVERT_EXPR: /* Unary + */
7802 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7803 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7810 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7811 name = TREE_OPERAND (t, 1);
7812 if (TREE_CODE (name) == BIT_NOT_EXPR)
7814 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7816 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7818 else if (TREE_CODE (name) == SCOPE_REF
7819 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7821 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7823 name = TREE_OPERAND (name, 1);
7824 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7826 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7827 name = build_nt (SCOPE_REF, base, name);
7829 else if (TREE_CODE (name) == BASELINK)
7830 name = tsubst_baselink (name,
7831 non_reference (TREE_TYPE (object)),
7835 name = tsubst_copy (name, args, complain, in_decl);
7836 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7842 case TRUNC_DIV_EXPR:
7844 case FLOOR_DIV_EXPR:
7845 case ROUND_DIV_EXPR:
7846 case EXACT_DIV_EXPR:
7850 case TRUNC_MOD_EXPR:
7851 case FLOOR_MOD_EXPR:
7852 case TRUTH_ANDIF_EXPR:
7853 case TRUTH_ORIF_EXPR:
7854 case TRUTH_AND_EXPR:
7873 case PREDECREMENT_EXPR:
7874 case PREINCREMENT_EXPR:
7875 case POSTDECREMENT_EXPR:
7876 case POSTINCREMENT_EXPR:
7878 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7879 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7882 return build_nt (code,
7883 tsubst_copy (TREE_OPERAND (t, 0), args,
7885 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7891 case PSEUDO_DTOR_EXPR:
7894 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7895 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7896 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7897 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7904 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7905 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7906 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7907 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7914 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7915 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7916 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7917 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7921 case TEMPLATE_ID_EXPR:
7923 /* Substituted template arguments */
7924 tree fn = TREE_OPERAND (t, 0);
7925 tree targs = TREE_OPERAND (t, 1);
7927 fn = tsubst_copy (fn, args, complain, in_decl);
7929 targs = tsubst_template_args (targs, args, complain, in_decl);
7931 return lookup_template_function (fn, targs);
7936 tree purpose, value, chain;
7938 if (t == void_list_node)
7941 purpose = TREE_PURPOSE (t);
7943 purpose = tsubst_copy (purpose, args, complain, in_decl);
7944 value = TREE_VALUE (t);
7946 value = tsubst_copy (value, args, complain, in_decl);
7947 chain = TREE_CHAIN (t);
7948 if (chain && chain != void_type_node)
7949 chain = tsubst_copy (chain, args, complain, in_decl);
7950 if (purpose == TREE_PURPOSE (t)
7951 && value == TREE_VALUE (t)
7952 && chain == TREE_CHAIN (t))
7954 return tree_cons (purpose, value, chain);
7961 case TEMPLATE_TYPE_PARM:
7962 case TEMPLATE_TEMPLATE_PARM:
7963 case BOUND_TEMPLATE_TEMPLATE_PARM:
7964 case TEMPLATE_PARM_INDEX:
7966 case REFERENCE_TYPE:
7972 case UNBOUND_CLASS_TEMPLATE:
7975 return tsubst (t, args, complain, in_decl);
7977 case IDENTIFIER_NODE:
7978 if (IDENTIFIER_TYPENAME_P (t))
7980 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7981 return mangle_conv_op_name_for_type (new_type);
7988 r = build_constructor
7989 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7990 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7991 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7996 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7998 tsubst (TREE_TYPE (t), args, complain, in_decl));
8000 case CLEANUP_POINT_EXPR:
8001 /* We shouldn't have built any of these during initial template
8002 generation. Instead, they should be built during instantiation
8003 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8011 /* Like tsubst_copy for expressions, etc. but also does semantic
8015 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8019 if (t == NULL_TREE || t == error_mark_node)
8022 if (EXPR_HAS_LOCATION (t))
8023 input_location = EXPR_LOCATION (t);
8024 if (STATEMENT_CODE_P (TREE_CODE (t)))
8025 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8027 switch (TREE_CODE (t))
8029 case STATEMENT_LIST:
8031 tree_stmt_iterator i;
8032 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8033 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8037 case CTOR_INITIALIZER:
8038 finish_mem_initializers (tsubst_initializer_list
8039 (TREE_OPERAND (t, 0), args));
8043 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8044 args, complain, in_decl));
8048 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8049 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8050 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8052 finish_expr_stmt (tmp);
8056 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8057 args, complain, in_decl));
8065 decl = DECL_EXPR_DECL (t);
8066 if (TREE_CODE (decl) == LABEL_DECL)
8067 finish_label_decl (DECL_NAME (decl));
8068 else if (TREE_CODE (decl) == USING_DECL)
8070 tree scope = DECL_INITIAL (decl);
8071 tree name = DECL_NAME (decl);
8074 scope = tsubst_expr (scope, args, complain, in_decl);
8075 decl = lookup_qualified_name (scope, name,
8076 /*is_type_p=*/false,
8077 /*complain=*/false);
8078 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8079 qualified_name_lookup_error (scope, name, decl);
8081 do_local_using_decl (decl, scope, name);
8085 init = DECL_INITIAL (decl);
8086 decl = tsubst (decl, args, complain, in_decl);
8087 if (decl != error_mark_node)
8090 DECL_INITIAL (decl) = error_mark_node;
8091 /* By marking the declaration as instantiated, we avoid
8092 trying to instantiate it. Since instantiate_decl can't
8093 handle local variables, and since we've already done
8094 all that needs to be done, that's the right thing to
8096 if (TREE_CODE (decl) == VAR_DECL)
8097 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8098 if (TREE_CODE (decl) == VAR_DECL
8099 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8100 /* Anonymous aggregates are a special case. */
8101 finish_anon_union (decl);
8104 maybe_push_decl (decl);
8105 if (TREE_CODE (decl) == VAR_DECL
8106 && DECL_PRETTY_FUNCTION_P (decl))
8108 /* For __PRETTY_FUNCTION__ we have to adjust the
8110 const char *const name
8111 = cxx_printable_name (current_function_decl, 2);
8112 init = cp_fname_init (name, &TREE_TYPE (decl));
8115 init = tsubst_expr (init, args, complain, in_decl);
8116 cp_finish_decl (decl, init, NULL_TREE, 0);
8121 /* A DECL_EXPR can also be used as an expression, in the condition
8122 clause of an if/for/while construct. */
8127 stmt = begin_for_stmt ();
8128 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8129 finish_for_init_stmt (stmt);
8130 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8131 finish_for_cond (tmp, stmt);
8132 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8133 finish_for_expr (tmp, stmt);
8134 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8135 finish_for_stmt (stmt);
8139 stmt = begin_while_stmt ();
8140 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8141 finish_while_stmt_cond (tmp, stmt);
8142 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8143 finish_while_stmt (stmt);
8147 stmt = begin_do_stmt ();
8148 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8149 finish_do_body (stmt);
8150 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8151 finish_do_stmt (tmp, stmt);
8155 stmt = begin_if_stmt ();
8156 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8157 finish_if_stmt_cond (tmp, stmt);
8158 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8159 finish_then_clause (stmt);
8161 if (ELSE_CLAUSE (t))
8163 begin_else_clause (stmt);
8164 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8165 finish_else_clause (stmt);
8168 finish_if_stmt (stmt);
8172 if (BIND_EXPR_BODY_BLOCK (t))
8173 stmt = begin_function_body ();
8175 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8176 ? BCS_TRY_BLOCK : 0);
8178 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8180 if (BIND_EXPR_BODY_BLOCK (t))
8181 finish_function_body (stmt);
8183 finish_compound_stmt (stmt);
8187 finish_break_stmt ();
8191 finish_continue_stmt ();
8195 stmt = begin_switch_stmt ();
8196 tmp = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
8197 finish_switch_cond (tmp, stmt);
8198 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
8199 finish_switch_stmt (stmt);
8202 case CASE_LABEL_EXPR:
8203 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8204 tsubst_expr (CASE_HIGH (t), args, complain,
8209 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8213 tmp = GOTO_DESTINATION (t);
8214 if (TREE_CODE (tmp) != LABEL_DECL)
8215 /* Computed goto's must be tsubst'd into. On the other hand,
8216 non-computed gotos must not be; the identifier in question
8217 will have no binding. */
8218 tmp = tsubst_expr (tmp, args, complain, in_decl);
8220 tmp = DECL_NAME (tmp);
8221 finish_goto_stmt (tmp);
8225 tmp = finish_asm_stmt
8226 (ASM_VOLATILE_P (t),
8227 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8228 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8229 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8230 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8232 tree asm_expr = tmp;
8233 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8234 asm_expr = TREE_OPERAND (asm_expr, 0);
8235 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8242 stmt = begin_try_block ();
8243 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8244 finish_cleanup_try_block (stmt);
8245 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8251 if (FN_TRY_BLOCK_P (t))
8252 stmt = begin_function_try_block ();
8254 stmt = begin_try_block ();
8256 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8258 if (FN_TRY_BLOCK_P (t))
8259 finish_function_try_block (stmt);
8261 finish_try_block (stmt);
8263 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8264 if (FN_TRY_BLOCK_P (t))
8265 finish_function_handler_sequence (stmt);
8267 finish_handler_sequence (stmt);
8275 stmt = begin_handler ();
8276 if (HANDLER_PARMS (t))
8278 decl = HANDLER_PARMS (t);
8279 decl = tsubst (decl, args, complain, in_decl);
8280 /* Prevent instantiate_decl from trying to instantiate
8281 this variable. We've already done all that needs to be
8283 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8287 finish_handler_parms (decl, stmt);
8288 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8289 finish_handler (stmt);
8294 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8298 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8300 return tsubst_copy_and_build (t, args, complain, in_decl,
8301 /*function_p=*/false);
8307 /* T is a postfix-expression that is not being used in a function
8308 call. Return the substituted version of T. */
8311 tsubst_non_call_postfix_expression (tree t, tree args,
8312 tsubst_flags_t complain,
8315 if (TREE_CODE (t) == SCOPE_REF)
8316 t = tsubst_qualified_id (t, args, complain, in_decl,
8317 /*done=*/false, /*address_p=*/false);
8319 t = tsubst_copy_and_build (t, args, complain, in_decl,
8320 /*function_p=*/false);
8325 /* Like tsubst but deals with expressions and performs semantic
8326 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8329 tsubst_copy_and_build (tree t,
8331 tsubst_flags_t complain,
8335 #define RECUR(NODE) \
8336 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8340 if (t == NULL_TREE || t == error_mark_node)
8343 switch (TREE_CODE (t))
8348 case IDENTIFIER_NODE:
8352 tree qualifying_class;
8353 bool non_integral_constant_expression_p;
8354 const char *error_msg;
8356 if (IDENTIFIER_TYPENAME_P (t))
8358 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8359 t = mangle_conv_op_name_for_type (new_type);
8362 /* Look up the name. */
8363 decl = lookup_name (t, 0);
8365 /* By convention, expressions use ERROR_MARK_NODE to indicate
8366 failure, not NULL_TREE. */
8367 if (decl == NULL_TREE)
8368 decl = error_mark_node;
8370 decl = finish_id_expression (t, decl, NULL_TREE,
8373 /*integral_constant_expression_p=*/false,
8374 /*allow_non_integral_constant_expression_p=*/false,
8375 &non_integral_constant_expression_p,
8379 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8380 decl = unqualified_name_lookup_error (decl);
8384 case TEMPLATE_ID_EXPR:
8387 tree template = RECUR (TREE_OPERAND (t, 0));
8388 tree targs = TREE_OPERAND (t, 1);
8391 targs = tsubst_template_args (targs, args, complain, in_decl);
8393 if (TREE_CODE (template) == COMPONENT_REF)
8395 object = TREE_OPERAND (template, 0);
8396 template = TREE_OPERAND (template, 1);
8400 template = lookup_template_function (template, targs);
8403 return build3 (COMPONENT_REF, TREE_TYPE (template),
8404 object, template, NULL_TREE);
8411 tree r = RECUR (TREE_OPERAND (t, 0));
8413 if (REFERENCE_REF_P (t))
8415 /* A type conversion to reference type will be enclosed in
8416 such an indirect ref, but the substitution of the cast
8417 will have also added such an indirect ref. */
8418 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8419 r = convert_from_reference (r);
8422 r = build_x_indirect_ref (r, "unary *");
8428 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8429 RECUR (TREE_OPERAND (t, 0)));
8432 return build_functional_cast
8433 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8434 RECUR (TREE_OPERAND (t, 0)));
8436 case REINTERPRET_CAST_EXPR:
8437 return build_reinterpret_cast
8438 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8439 RECUR (TREE_OPERAND (t, 0)));
8441 case CONST_CAST_EXPR:
8442 return build_const_cast
8443 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8444 RECUR (TREE_OPERAND (t, 0)));
8446 case DYNAMIC_CAST_EXPR:
8447 return build_dynamic_cast
8448 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8449 RECUR (TREE_OPERAND (t, 0)));
8451 case STATIC_CAST_EXPR:
8452 return build_static_cast
8453 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8454 RECUR (TREE_OPERAND (t, 0)));
8456 case POSTDECREMENT_EXPR:
8457 case POSTINCREMENT_EXPR:
8458 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8459 args, complain, in_decl);
8460 return build_x_unary_op (TREE_CODE (t), op1);
8462 case PREDECREMENT_EXPR:
8463 case PREINCREMENT_EXPR:
8467 case TRUTH_NOT_EXPR:
8468 case CONVERT_EXPR: /* Unary + */
8471 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8474 op1 = TREE_OPERAND (t, 0);
8475 if (TREE_CODE (op1) == SCOPE_REF)
8476 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8477 /*done=*/true, /*address_p=*/true);
8479 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8481 if (TREE_CODE (op1) == LABEL_DECL)
8482 return finish_label_address_expr (DECL_NAME (op1));
8483 return build_x_unary_op (ADDR_EXPR, op1);
8488 case TRUNC_DIV_EXPR:
8490 case FLOOR_DIV_EXPR:
8491 case ROUND_DIV_EXPR:
8492 case EXACT_DIV_EXPR:
8496 case TRUNC_MOD_EXPR:
8497 case FLOOR_MOD_EXPR:
8498 case TRUTH_ANDIF_EXPR:
8499 case TRUTH_ORIF_EXPR:
8500 case TRUTH_AND_EXPR:
8516 return build_x_binary_op
8518 RECUR (TREE_OPERAND (t, 0)),
8519 RECUR (TREE_OPERAND (t, 1)),
8520 /*overloaded_p=*/NULL);
8523 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8524 /*address_p=*/false);
8527 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8530 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)),
8531 NULL_TREE, NULL_TREE);
8533 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8534 args, complain, in_decl);
8535 /* Remember that there was a reference to this entity. */
8538 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8542 op1 = TREE_OPERAND (t, 0);
8545 /* When there are no ARGS, we are trying to evaluate a
8546 non-dependent expression from the parser. Trying to do
8547 the substitutions may not work. */
8549 op1 = TREE_TYPE (op1);
8558 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8560 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8564 tree r = build_x_modify_expr
8565 (RECUR (TREE_OPERAND (t, 0)),
8566 TREE_CODE (TREE_OPERAND (t, 1)),
8567 RECUR (TREE_OPERAND (t, 2)));
8568 /* TREE_NO_WARNING must be set if either the expression was
8569 parenthesized or it uses an operator such as >>= rather
8570 than plain assignment. In the former case, it was already
8571 set and must be copied. In the latter case,
8572 build_x_modify_expr sets it and it must not be reset
8574 if (TREE_NO_WARNING (t))
8575 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8580 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8581 args, complain, in_decl);
8582 /* Remember that there was a reference to this entity. */
8585 return build_x_arrow (op1);
8589 (RECUR (TREE_OPERAND (t, 0)),
8590 RECUR (TREE_OPERAND (t, 1)),
8591 RECUR (TREE_OPERAND (t, 2)),
8592 RECUR (TREE_OPERAND (t, 3)),
8593 NEW_EXPR_USE_GLOBAL (t));
8596 return delete_sanity
8597 (RECUR (TREE_OPERAND (t, 0)),
8598 RECUR (TREE_OPERAND (t, 1)),
8599 DELETE_EXPR_USE_VEC (t),
8600 DELETE_EXPR_USE_GLOBAL (t));
8603 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8604 RECUR (TREE_OPERAND (t, 1)));
8613 function = TREE_OPERAND (t, 0);
8614 /* When we parsed the expression, we determined whether or
8615 not Koenig lookup should be performed. */
8616 koenig_p = KOENIG_LOOKUP_P (t);
8617 if (TREE_CODE (function) == SCOPE_REF)
8620 function = tsubst_qualified_id (function, args, complain, in_decl,
8622 /*address_p=*/false);
8626 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8627 && (TREE_CODE (TREE_OPERAND (function, 1))
8629 function = tsubst_copy_and_build (function, args, complain,
8632 if (BASELINK_P (function))
8636 call_args = RECUR (TREE_OPERAND (t, 1));
8638 /* We do not perform argument-dependent lookup if normal
8639 lookup finds a non-function, in accordance with the
8640 expected resolution of DR 218. */
8642 && ((is_overloaded_fn (function)
8643 /* If lookup found a member function, the Koenig lookup is
8644 not appropriate, even if an unqualified-name was used
8645 to denote the function. */
8646 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8647 || TREE_CODE (function) == IDENTIFIER_NODE))
8648 function = perform_koenig_lookup (function, call_args);
8650 if (TREE_CODE (function) == IDENTIFIER_NODE)
8652 unqualified_name_lookup_error (function);
8653 return error_mark_node;
8656 /* Remember that there was a reference to this entity. */
8657 if (DECL_P (function))
8658 mark_used (function);
8660 if (TREE_CODE (function) == OFFSET_REF)
8661 return build_offset_ref_call_from_tree (function, call_args);
8662 if (TREE_CODE (function) == COMPONENT_REF)
8664 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8665 return finish_call_expr (function, call_args,
8666 /*disallow_virtual=*/false,
8667 /*koenig_p=*/false);
8669 return (build_new_method_call
8670 (TREE_OPERAND (function, 0),
8671 TREE_OPERAND (function, 1),
8672 call_args, NULL_TREE,
8673 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8675 return finish_call_expr (function, call_args,
8676 /*disallow_virtual=*/qualified_p,
8681 return build_x_conditional_expr
8682 (RECUR (TREE_OPERAND (t, 0)),
8683 RECUR (TREE_OPERAND (t, 1)),
8684 RECUR (TREE_OPERAND (t, 2)));
8686 case PSEUDO_DTOR_EXPR:
8687 return finish_pseudo_destructor_expr
8688 (RECUR (TREE_OPERAND (t, 0)),
8689 RECUR (TREE_OPERAND (t, 1)),
8690 RECUR (TREE_OPERAND (t, 2)));
8694 tree purpose, value, chain;
8696 if (t == void_list_node)
8699 purpose = TREE_PURPOSE (t);
8701 purpose = RECUR (purpose);
8702 value = TREE_VALUE (t);
8704 value = RECUR (value);
8705 chain = TREE_CHAIN (t);
8706 if (chain && chain != void_type_node)
8707 chain = RECUR (chain);
8708 if (purpose == TREE_PURPOSE (t)
8709 && value == TREE_VALUE (t)
8710 && chain == TREE_CHAIN (t))
8712 return tree_cons (purpose, value, chain);
8720 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8721 args, complain, in_decl);
8722 /* Remember that there was a reference to this entity. */
8723 if (DECL_P (object))
8726 member = TREE_OPERAND (t, 1);
8727 if (BASELINK_P (member))
8728 member = tsubst_baselink (member,
8729 non_reference (TREE_TYPE (object)),
8730 args, complain, in_decl);
8732 member = tsubst_copy (member, args, complain, in_decl);
8734 if (member == error_mark_node)
8735 return error_mark_node;
8736 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8738 if (TREE_CODE (member) == BIT_NOT_EXPR)
8739 return finish_pseudo_destructor_expr (object,
8741 TREE_TYPE (object));
8742 else if (TREE_CODE (member) == SCOPE_REF
8743 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8744 return finish_pseudo_destructor_expr (object,
8746 TREE_TYPE (object));
8748 else if (TREE_CODE (member) == SCOPE_REF
8749 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8754 /* Lookup the template functions now that we know what the
8756 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8757 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8758 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8759 /*is_type_p=*/false,
8760 /*complain=*/false);
8761 if (BASELINK_P (member))
8763 BASELINK_FUNCTIONS (member)
8764 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8766 member = (adjust_result_of_qualified_name_lookup
8767 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8768 TREE_TYPE (object)));
8772 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8774 return error_mark_node;
8777 else if (TREE_CODE (member) == SCOPE_REF
8778 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8779 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8781 if (complain & tf_error)
8783 if (TYPE_P (TREE_OPERAND (member, 0)))
8784 error ("%qT is not a class or namespace",
8785 TREE_OPERAND (member, 0));
8787 error ("%qD is not a class or namespace",
8788 TREE_OPERAND (member, 0));
8790 return error_mark_node;
8792 else if (TREE_CODE (member) == FIELD_DECL)
8793 return finish_non_static_data_member (member, object, NULL_TREE);
8795 return finish_class_member_access_expr (object, member);
8800 (RECUR (TREE_OPERAND (t, 0)));
8806 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8809 /* digest_init will do the wrong thing if we let it. */
8810 if (type && TYPE_PTRMEMFUNC_P (type))
8814 /* We do not want to process the purpose of aggregate
8815 initializers as they are identifier nodes which will be
8816 looked up by digest_init. */
8817 purpose_p = !(type && IS_AGGR_TYPE (type));
8818 for (elts = CONSTRUCTOR_ELTS (t);
8820 elts = TREE_CHAIN (elts))
8822 tree purpose = TREE_PURPOSE (elts);
8823 tree value = TREE_VALUE (elts);
8825 if (purpose && purpose_p)
8826 purpose = RECUR (purpose);
8827 value = RECUR (value);
8828 r = tree_cons (purpose, value, r);
8831 r = build_constructor (NULL_TREE, nreverse (r));
8832 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8835 return digest_init (type, r, 0);
8841 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8842 if (TYPE_P (operand_0))
8843 return get_typeid (operand_0);
8844 return build_typeid (operand_0);
8854 tree r = tsubst_copy (t, args, complain, in_decl);
8856 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8857 /* If the original type was a reference, we'll be wrapped in
8858 the appropriate INDIRECT_REF. */
8859 r = convert_from_reference (r);
8864 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8865 tsubst_copy (TREE_TYPE (t), args, complain,
8869 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8873 tree old_stmt_expr = cur_stmt_expr;
8874 tree stmt_expr = begin_stmt_expr ();
8876 cur_stmt_expr = stmt_expr;
8877 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8878 stmt_expr = finish_stmt_expr (stmt_expr, false);
8879 cur_stmt_expr = old_stmt_expr;
8885 t = tsubst_copy (t, args, complain, in_decl);
8886 /* As in finish_id_expression, we resolve enumeration constants
8887 to their underlying values. */
8888 if (TREE_CODE (t) == CONST_DECL)
8889 return DECL_INITIAL (t);
8893 return tsubst_copy (t, args, complain, in_decl);
8899 /* Verify that the instantiated ARGS are valid. For type arguments,
8900 make sure that the type's linkage is ok. For non-type arguments,
8901 make sure they are constants if they are integral or enumerations.
8902 Emit an error under control of COMPLAIN, and return TRUE on error. */
8905 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8907 int ix, len = DECL_NTPARMS (tmpl);
8908 bool result = false;
8910 for (ix = 0; ix != len; ix++)
8912 tree t = TREE_VEC_ELT (args, ix);
8916 /* [basic.link]: A name with no linkage (notably, the name
8917 of a class or enumeration declared in a local scope)
8918 shall not be used to declare an entity with linkage.
8919 This implies that names with no linkage cannot be used as
8920 template arguments. */
8921 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8925 if (!(complain & tf_error))
8927 else if (TYPE_ANONYMOUS_P (nt))
8928 error ("%qT uses anonymous type", t);
8930 error ("%qT uses local type %qT", t, nt);
8933 /* In order to avoid all sorts of complications, we do not
8934 allow variably-modified types as template arguments. */
8935 else if (variably_modified_type_p (t, NULL_TREE))
8937 if (complain & tf_error)
8938 error ("%qT is a variably modified type", t);
8942 /* A non-type argument of integral or enumerated type must be a
8944 else if (TREE_TYPE (t)
8945 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8946 && !TREE_CONSTANT (t))
8948 if (complain & tf_error)
8949 error ("integral expression %qE is not constant", t);
8953 if (result && complain & tf_error)
8954 error (" trying to instantiate %qD", tmpl);
8958 /* Instantiate the indicated variable or function template TMPL with
8959 the template arguments in TARG_PTR. */
8962 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8968 if (tmpl == error_mark_node)
8969 return error_mark_node;
8971 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
8973 /* If this function is a clone, handle it specially. */
8974 if (DECL_CLONED_FUNCTION_P (tmpl))
8979 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8981 if (spec == error_mark_node)
8982 return error_mark_node;
8984 /* Look for the clone. */
8985 FOR_EACH_CLONE (clone, spec)
8986 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8988 /* We should always have found the clone by now. */
8993 /* Check to see if we already have this specialization. */
8994 spec = retrieve_specialization (tmpl, targ_ptr,
8995 /*class_specializations_p=*/false);
8996 if (spec != NULL_TREE)
8999 gen_tmpl = most_general_template (tmpl);
9000 if (tmpl != gen_tmpl)
9002 /* The TMPL is a partial instantiation. To get a full set of
9003 arguments we must add the arguments used to perform the
9004 partial instantiation. */
9005 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9008 /* Check to see if we already have this specialization. */
9009 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9010 /*class_specializations_p=*/false);
9011 if (spec != NULL_TREE)
9015 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9017 return error_mark_node;
9019 /* We are building a FUNCTION_DECL, during which the access of its
9020 parameters and return types have to be checked. However this
9021 FUNCTION_DECL which is the desired context for access checking
9022 is not built yet. We solve this chicken-and-egg problem by
9023 deferring all checks until we have the FUNCTION_DECL. */
9024 push_deferring_access_checks (dk_deferred);
9026 /* Substitute template parameters. */
9027 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9028 targ_ptr, complain, gen_tmpl);
9030 /* Now we know the specialization, compute access previously
9032 push_access_scope (fndecl);
9033 perform_deferred_access_checks ();
9034 pop_access_scope (fndecl);
9035 pop_deferring_access_checks ();
9037 /* The DECL_TI_TEMPLATE should always be the immediate parent
9038 template, not the most general template. */
9039 DECL_TI_TEMPLATE (fndecl) = tmpl;
9041 /* If we've just instantiated the main entry point for a function,
9042 instantiate all the alternate entry points as well. We do this
9043 by cloning the instantiation of the main entry point, not by
9044 instantiating the template clones. */
9045 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9046 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9051 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9052 arguments that are being used when calling it. TARGS is a vector
9053 into which the deduced template arguments are placed.
9055 Return zero for success, 2 for an incomplete match that doesn't resolve
9056 all the types, and 1 for complete failure. An error message will be
9057 printed only for an incomplete match.
9059 If FN is a conversion operator, or we are trying to produce a specific
9060 specialization, RETURN_TYPE is the return type desired.
9062 The EXPLICIT_TARGS are explicit template arguments provided via a
9065 The parameter STRICT is one of:
9068 We are deducing arguments for a function call, as in
9072 We are deducing arguments for a conversion function, as in
9076 We are deducing arguments when doing an explicit instantiation
9077 as in [temp.explicit], when determining an explicit specialization
9078 as in [temp.expl.spec], or when taking the address of a function
9079 template, as in [temp.deduct.funcaddr].
9082 We are deducing arguments when calculating the partial
9083 ordering between specializations of function or class
9084 templates, as in [temp.func.order] and [temp.class.order].
9086 LEN is the number of parms to consider before returning success, or -1
9087 for all. This is used in partial ordering to avoid comparing parms for
9088 which no actual argument was passed, since they are not considered in
9089 overload resolution (and are explicitly excluded from consideration in
9090 partial ordering in [temp.func.order]/6). */
9093 fn_type_unification (tree fn,
9094 tree explicit_targs,
9098 unification_kind_t strict,
9105 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9107 fntype = TREE_TYPE (fn);
9112 The specified template arguments must match the template
9113 parameters in kind (i.e., type, nontype, template), and there
9114 must not be more arguments than there are parameters;
9115 otherwise type deduction fails.
9117 Nontype arguments must match the types of the corresponding
9118 nontype template parameters, or must be convertible to the
9119 types of the corresponding nontype parameters as specified in
9120 _temp.arg.nontype_, otherwise type deduction fails.
9122 All references in the function type of the function template
9123 to the corresponding template parameters are replaced by the
9124 specified template argument values. If a substitution in a
9125 template parameter or in the function type of the function
9126 template results in an invalid type, type deduction fails. */
9128 tree converted_args;
9132 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9133 explicit_targs, NULL_TREE, tf_none,
9134 /*require_all_arguments=*/0));
9135 if (converted_args == error_mark_node)
9138 /* Substitute the explicit args into the function type. This is
9139 necessary so that, for instance, explicitly declared function
9140 arguments can match null pointed constants. If we were given
9141 an incomplete set of explicit args, we must not do semantic
9142 processing during substitution as we could create partial
9144 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9145 processing_template_decl += incomplete;
9146 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9147 processing_template_decl -= incomplete;
9149 if (fntype == error_mark_node)
9152 /* Place the explicitly specified arguments in TARGS. */
9153 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9154 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9157 parms = TYPE_ARG_TYPES (fntype);
9158 /* Never do unification on the 'this' parameter. */
9159 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9160 parms = TREE_CHAIN (parms);
9164 /* We've been given a return type to match, prepend it. */
9165 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9166 args = tree_cons (NULL_TREE, return_type, args);
9171 /* We allow incomplete unification without an error message here
9172 because the standard doesn't seem to explicitly prohibit it. Our
9173 callers must be ready to deal with unification failures in any
9175 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9176 targs, parms, args, /*subr=*/0,
9177 strict, /*allow_incomplete*/1, len);
9180 /* All is well so far. Now, check:
9184 When all template arguments have been deduced, all uses of
9185 template parameters in nondeduced contexts are replaced with
9186 the corresponding deduced argument values. If the
9187 substitution results in an invalid type, as described above,
9188 type deduction fails. */
9189 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9196 /* Adjust types before performing type deduction, as described in
9197 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9198 sections are symmetric. PARM is the type of a function parameter
9199 or the return type of the conversion function. ARG is the type of
9200 the argument passed to the call, or the type of the value
9201 initialized with the result of the conversion function. */
9204 maybe_adjust_types_for_deduction (unification_kind_t strict,
9217 /* Swap PARM and ARG throughout the remainder of this
9218 function; the handling is precisely symmetric since PARM
9219 will initialize ARG rather than vice versa. */
9227 /* There is nothing to do in this case. */
9231 /* DR 214. [temp.func.order] is underspecified, and leads to no
9232 ordering between things like `T *' and `T const &' for `U *'.
9233 The former has T=U and the latter T=U*. The former looks more
9234 specialized and John Spicer considers it well-formed (the EDG
9235 compiler accepts it).
9237 John also confirms that deduction should proceed as in a function
9238 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
9239 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
9240 to an actual call can have such a type.
9242 If both ARG and PARM are REFERENCE_TYPE, we change neither.
9243 If only ARG is a REFERENCE_TYPE, we look through that and then
9244 proceed as with DEDUCE_CALL (which could further convert it). */
9245 if (TREE_CODE (*arg) == REFERENCE_TYPE)
9247 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9249 *arg = TREE_TYPE (*arg);
9256 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9258 /* [temp.deduct.call]
9260 If P is not a reference type:
9262 --If A is an array type, the pointer type produced by the
9263 array-to-pointer standard conversion (_conv.array_) is
9264 used in place of A for type deduction; otherwise,
9266 --If A is a function type, the pointer type produced by
9267 the function-to-pointer standard conversion
9268 (_conv.func_) is used in place of A for type deduction;
9271 --If A is a cv-qualified type, the top level
9272 cv-qualifiers of A's type are ignored for type
9274 if (TREE_CODE (*arg) == ARRAY_TYPE)
9275 *arg = build_pointer_type (TREE_TYPE (*arg));
9276 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9277 *arg = build_pointer_type (*arg);
9279 *arg = TYPE_MAIN_VARIANT (*arg);
9282 /* [temp.deduct.call]
9284 If P is a cv-qualified type, the top level cv-qualifiers
9285 of P's type are ignored for type deduction. If P is a
9286 reference type, the type referred to by P is used for
9288 *parm = TYPE_MAIN_VARIANT (*parm);
9289 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9291 *parm = TREE_TYPE (*parm);
9292 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9295 /* DR 322. For conversion deduction, remove a reference type on parm
9296 too (which has been swapped into ARG). */
9297 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9298 *arg = TREE_TYPE (*arg);
9303 /* Most parms like fn_type_unification.
9305 If SUBR is 1, we're being called recursively (to unify the
9306 arguments of a function or method parameter of a function
9310 type_unification_real (tree tparms,
9315 unification_kind_t strict,
9316 int allow_incomplete,
9321 int ntparms = TREE_VEC_LENGTH (tparms);
9323 int saw_undeduced = 0;
9327 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9328 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9329 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9330 gcc_assert (ntparms > 0);
9335 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9336 | UNIFY_ALLOW_DERIVED);
9340 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9344 sub_strict = UNIFY_ALLOW_NONE;
9348 sub_strict = UNIFY_ALLOW_NONE;
9364 && parms != void_list_node
9366 && args != void_list_node)
9368 parm = TREE_VALUE (parms);
9369 parms = TREE_CHAIN (parms);
9370 arg = TREE_VALUE (args);
9371 args = TREE_CHAIN (args);
9373 if (arg == error_mark_node)
9375 if (arg == unknown_type_node)
9376 /* We can't deduce anything from this, but we might get all the
9377 template args from other function args. */
9380 /* Conversions will be performed on a function argument that
9381 corresponds with a function parameter that contains only
9382 non-deducible template parameters and explicitly specified
9383 template parameters. */
9384 if (!uses_template_parms (parm))
9389 type = TREE_TYPE (arg);
9393 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
9395 if (same_type_p (parm, type))
9399 /* It might work; we shouldn't check now, because we might
9400 get into infinite recursion. Overload resolution will
9409 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9410 if (type_unknown_p (arg))
9412 /* [temp.deduct.type] A template-argument can be deduced from
9413 a pointer to function or pointer to member function
9414 argument if the set of overloaded functions does not
9415 contain function templates and at most one of a set of
9416 overloaded functions provides a unique match. */
9418 if (resolve_overloaded_unification
9419 (tparms, targs, parm, arg, strict, sub_strict)
9424 arg = TREE_TYPE (arg);
9425 if (arg == error_mark_node)
9430 int arg_strict = sub_strict;
9433 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9435 if (unify (tparms, targs, parm, arg, arg_strict))
9439 /* Are we done with the interesting parms? */
9443 /* Fail if we've reached the end of the parm list, and more args
9444 are present, and the parm list isn't variadic. */
9445 if (args && args != void_list_node && parms == void_list_node)
9447 /* Fail if parms are left and they don't have default values. */
9449 && parms != void_list_node
9450 && TREE_PURPOSE (parms) == NULL_TREE)
9455 for (i = 0; i < ntparms; i++)
9456 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
9458 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9460 /* If this is an undeduced nontype parameter that depends on
9461 a type parameter, try another pass; its type may have been
9462 deduced from a later argument than the one from which
9463 this parameter can be deduced. */
9464 if (TREE_CODE (tparm) == PARM_DECL
9465 && uses_template_parms (TREE_TYPE (tparm))
9466 && !saw_undeduced++)
9469 if (!allow_incomplete)
9470 error ("incomplete type unification");
9476 /* Subroutine of type_unification_real. Args are like the variables at the
9477 call site. ARG is an overloaded function (or template-id); we try
9478 deducing template args from each of the overloads, and if only one
9479 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9482 resolve_overloaded_unification (tree tparms,
9486 unification_kind_t strict,
9489 tree tempargs = copy_node (targs);
9493 if (TREE_CODE (arg) == ADDR_EXPR)
9495 arg = TREE_OPERAND (arg, 0);
9501 if (TREE_CODE (arg) == COMPONENT_REF)
9502 /* Handle `&x' where `x' is some static or non-static member
9504 arg = TREE_OPERAND (arg, 1);
9506 if (TREE_CODE (arg) == OFFSET_REF)
9507 arg = TREE_OPERAND (arg, 1);
9509 /* Strip baselink information. */
9510 if (BASELINK_P (arg))
9511 arg = BASELINK_FUNCTIONS (arg);
9513 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9515 /* If we got some explicit template args, we need to plug them into
9516 the affected templates before we try to unify, in case the
9517 explicit args will completely resolve the templates in question. */
9519 tree expl_subargs = TREE_OPERAND (arg, 1);
9520 arg = TREE_OPERAND (arg, 0);
9522 for (; arg; arg = OVL_NEXT (arg))
9524 tree fn = OVL_CURRENT (arg);
9527 if (TREE_CODE (fn) != TEMPLATE_DECL)
9530 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
9534 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9535 good += try_one_overload (tparms, targs, tempargs, parm,
9536 elem, strict, sub_strict, addr_p);
9542 gcc_assert (TREE_CODE (arg) == OVERLOAD
9543 || TREE_CODE (arg) == FUNCTION_DECL);
9545 for (; arg; arg = OVL_NEXT (arg))
9546 good += try_one_overload (tparms, targs, tempargs, parm,
9547 TREE_TYPE (OVL_CURRENT (arg)),
9548 strict, sub_strict, addr_p);
9551 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9552 to function or pointer to member function argument if the set of
9553 overloaded functions does not contain function templates and at most
9554 one of a set of overloaded functions provides a unique match.
9556 So if we found multiple possibilities, we return success but don't
9561 int i = TREE_VEC_LENGTH (targs);
9563 if (TREE_VEC_ELT (tempargs, i))
9564 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9572 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9573 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9574 different overloads deduce different arguments for a given parm.
9575 ADDR_P is true if the expression for which deduction is being
9576 performed was of the form "& fn" rather than simply "fn".
9578 Returns 1 on success. */
9581 try_one_overload (tree tparms,
9586 unification_kind_t strict,
9594 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9595 to function or pointer to member function argument if the set of
9596 overloaded functions does not contain function templates and at most
9597 one of a set of overloaded functions provides a unique match.
9599 So if this is a template, just return success. */
9601 if (uses_template_parms (arg))
9604 if (TREE_CODE (arg) == METHOD_TYPE)
9605 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9607 arg = build_pointer_type (arg);
9609 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9611 /* We don't copy orig_targs for this because if we have already deduced
9612 some template args from previous args, unify would complain when we
9613 try to deduce a template parameter for the same argument, even though
9614 there isn't really a conflict. */
9615 nargs = TREE_VEC_LENGTH (targs);
9616 tempargs = make_tree_vec (nargs);
9618 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9621 /* First make sure we didn't deduce anything that conflicts with
9622 explicitly specified args. */
9623 for (i = nargs; i--; )
9625 tree elt = TREE_VEC_ELT (tempargs, i);
9626 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9628 if (elt == NULL_TREE)
9630 else if (uses_template_parms (elt))
9632 /* Since we're unifying against ourselves, we will fill in template
9633 args used in the function parm list with our own template parms.
9635 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9638 else if (oldelt && ! template_args_equal (oldelt, elt))
9642 for (i = nargs; i--; )
9644 tree elt = TREE_VEC_ELT (tempargs, i);
9647 TREE_VEC_ELT (targs, i) = elt;
9653 /* Verify that nondeduce template argument agrees with the type
9654 obtained from argument deduction. Return nonzero if the
9659 struct A { typedef int X; };
9660 template <class T, class U> struct C {};
9661 template <class T> struct C<T, typename T::X> {};
9663 Then with the instantiation `C<A, int>', we can deduce that
9664 `T' is `A' but unify () does not check whether `typename T::X'
9665 is `int'. This function ensure that they agree.
9667 TARGS, PARMS are the same as the arguments of unify.
9668 ARGS contains template arguments from all levels. */
9671 verify_class_unification (tree targs, tree parms, tree args)
9673 parms = tsubst (parms, add_outermost_template_args (args, targs),
9674 tf_none, NULL_TREE);
9675 if (parms == error_mark_node)
9678 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9681 /* PARM is a template class (perhaps with unbound template
9682 parameters). ARG is a fully instantiated type. If ARG can be
9683 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9684 TARGS are as for unify. */
9687 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9691 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9692 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9693 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9696 /* We need to make a new template argument vector for the call to
9697 unify. If we used TARGS, we'd clutter it up with the result of
9698 the attempted unification, even if this class didn't work out.
9699 We also don't want to commit ourselves to all the unifications
9700 we've already done, since unification is supposed to be done on
9701 an argument-by-argument basis. In other words, consider the
9702 following pathological case:
9704 template <int I, int J, int K>
9707 template <int I, int J>
9708 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9710 template <int I, int J, int K>
9711 void f(S<I, J, K>, S<I, I, I>);
9720 Now, by the time we consider the unification involving `s2', we
9721 already know that we must have `f<0, 0, 0>'. But, even though
9722 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9723 because there are two ways to unify base classes of S<0, 1, 2>
9724 with S<I, I, I>. If we kept the already deduced knowledge, we
9725 would reject the possibility I=1. */
9726 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9728 /* If unification failed, we're done. */
9729 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9730 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9736 /* Given a template type PARM and a class type ARG, find the unique
9737 base type in ARG that is an instance of PARM. We do not examine
9738 ARG itself; only its base-classes. If there is not exactly one
9739 appropriate base class, return NULL_TREE. PARM may be the type of
9740 a partial specialization, as well as a plain template type. Used
9744 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9746 tree rval = NULL_TREE;
9749 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9751 binfo = TYPE_BINFO (complete_type (arg));
9753 /* The type could not be completed. */
9756 /* Walk in inheritance graph order. The search order is not
9757 important, and this avoids multiple walks of virtual bases. */
9758 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9760 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9764 /* If there is more than one satisfactory baseclass, then:
9768 If they yield more than one possible deduced A, the type
9772 if (rval && !same_type_p (r, rval))
9782 /* Returns the level of DECL, which declares a template parameter. */
9785 template_decl_level (tree decl)
9787 switch (TREE_CODE (decl))
9791 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9794 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9802 /* Decide whether ARG can be unified with PARM, considering only the
9803 cv-qualifiers of each type, given STRICT as documented for unify.
9804 Returns nonzero iff the unification is OK on that basis. */
9807 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9809 int arg_quals = cp_type_quals (arg);
9810 int parm_quals = cp_type_quals (parm);
9812 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9813 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9815 /* Although a CVR qualifier is ignored when being applied to a
9816 substituted template parameter ([8.3.2]/1 for example), that
9817 does not apply during deduction [14.8.2.4]/1, (even though
9818 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9819 this). Except when we're allowing additional CV qualifiers
9820 at the outer level [14.8.2.1]/3,1st bullet. */
9821 if ((TREE_CODE (arg) == REFERENCE_TYPE
9822 || TREE_CODE (arg) == FUNCTION_TYPE
9823 || TREE_CODE (arg) == METHOD_TYPE)
9824 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9827 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9828 && (parm_quals & TYPE_QUAL_RESTRICT))
9832 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9833 && (arg_quals & parm_quals) != parm_quals)
9836 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9837 && (parm_quals & arg_quals) != arg_quals)
9843 /* Takes parameters as for type_unification. Returns 0 if the
9844 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9845 bitwise or of the following flags:
9848 Require an exact match between PARM and ARG.
9849 UNIFY_ALLOW_MORE_CV_QUAL:
9850 Allow the deduced ARG to be more cv-qualified (by qualification
9851 conversion) than ARG.
9852 UNIFY_ALLOW_LESS_CV_QUAL:
9853 Allow the deduced ARG to be less cv-qualified than ARG.
9854 UNIFY_ALLOW_DERIVED:
9855 Allow the deduced ARG to be a template base class of ARG,
9856 or a pointer to a template base class of the type pointed to by
9858 UNIFY_ALLOW_INTEGER:
9859 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9860 case for more information.
9861 UNIFY_ALLOW_OUTER_LEVEL:
9862 This is the outermost level of a deduction. Used to determine validity
9863 of qualification conversions. A valid qualification conversion must
9864 have const qualified pointers leading up to the inner type which
9865 requires additional CV quals, except at the outer level, where const
9866 is not required [conv.qual]. It would be normal to set this flag in
9867 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9868 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9869 This is the outermost level of a deduction, and PARM can be more CV
9870 qualified at this point.
9871 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9872 This is the outermost level of a deduction, and PARM can be less CV
9873 qualified at this point. */
9876 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9881 int strict_in = strict;
9883 /* I don't think this will do the right thing with respect to types.
9884 But the only case I've seen it in so far has been array bounds, where
9885 signedness is the only information lost, and I think that will be
9887 while (TREE_CODE (parm) == NOP_EXPR)
9888 parm = TREE_OPERAND (parm, 0);
9890 if (arg == error_mark_node)
9892 if (arg == unknown_type_node)
9893 /* We can't deduce anything from this, but we might get all the
9894 template args from other function args. */
9897 /* If PARM uses template parameters, then we can't bail out here,
9898 even if ARG == PARM, since we won't record unifications for the
9899 template parameters. We might need them if we're trying to
9900 figure out which of two things is more specialized. */
9901 if (arg == parm && !uses_template_parms (parm))
9904 /* Immediately reject some pairs that won't unify because of
9905 cv-qualification mismatches. */
9906 if (TREE_CODE (arg) == TREE_CODE (parm)
9908 /* It is the elements of the array which hold the cv quals of an array
9909 type, and the elements might be template type parms. We'll check
9911 && TREE_CODE (arg) != ARRAY_TYPE
9912 /* We check the cv-qualifiers when unifying with template type
9913 parameters below. We want to allow ARG `const T' to unify with
9914 PARM `T' for example, when computing which of two templates
9915 is more specialized, for example. */
9916 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9917 && !check_cv_quals_for_unify (strict_in, arg, parm))
9920 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9921 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9922 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9923 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9924 strict &= ~UNIFY_ALLOW_DERIVED;
9925 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9926 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9928 switch (TREE_CODE (parm))
9932 case UNBOUND_CLASS_TEMPLATE:
9933 /* In a type which contains a nested-name-specifier, template
9934 argument values cannot be deduced for template parameters used
9935 within the nested-name-specifier. */
9938 case TEMPLATE_TYPE_PARM:
9939 case TEMPLATE_TEMPLATE_PARM:
9940 case BOUND_TEMPLATE_TEMPLATE_PARM:
9941 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9943 if (TEMPLATE_TYPE_LEVEL (parm)
9944 != template_decl_level (tparm))
9945 /* The PARM is not one we're trying to unify. Just check
9946 to see if it matches ARG. */
9947 return (TREE_CODE (arg) == TREE_CODE (parm)
9948 && same_type_p (parm, arg)) ? 0 : 1;
9949 idx = TEMPLATE_TYPE_IDX (parm);
9950 targ = TREE_VEC_ELT (targs, idx);
9951 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9953 /* Check for mixed types and values. */
9954 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9955 && TREE_CODE (tparm) != TYPE_DECL)
9956 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9957 && TREE_CODE (tparm) != TEMPLATE_DECL))
9960 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9962 /* ARG must be constructed from a template class or a template
9963 template parameter. */
9964 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9965 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9969 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9970 tree parmvec = TYPE_TI_ARGS (parm);
9971 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9973 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9976 /* The parameter and argument roles have to be switched here
9977 in order to handle default arguments properly. For example,
9978 template<template <class> class TT> void f(TT<int>)
9979 should be able to accept vector<int> which comes from
9980 template <class T, class Allocator = allocator>
9983 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9987 /* Deduce arguments T, i from TT<T> or TT<i>.
9988 We check each element of PARMVEC and ARGVEC individually
9989 rather than the whole TREE_VEC since they can have
9990 different number of elements. */
9992 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9994 if (unify (tparms, targs,
9995 TREE_VEC_ELT (parmvec, i),
9996 TREE_VEC_ELT (argvec, i),
10001 arg = TYPE_TI_TEMPLATE (arg);
10003 /* Fall through to deduce template name. */
10006 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10007 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10009 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
10011 /* Simple cases: Value already set, does match or doesn't. */
10012 if (targ != NULL_TREE && template_args_equal (targ, arg))
10019 /* If PARM is `const T' and ARG is only `int', we don't have
10020 a match unless we are allowing additional qualification.
10021 If ARG is `const int' and PARM is just `T' that's OK;
10022 that binds `const int' to `T'. */
10023 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10027 /* Consider the case where ARG is `const volatile int' and
10028 PARM is `const T'. Then, T should be `volatile int'. */
10029 arg = cp_build_qualified_type_real
10030 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10031 if (arg == error_mark_node)
10034 /* Simple cases: Value already set, does match or doesn't. */
10035 if (targ != NULL_TREE && same_type_p (targ, arg))
10040 /* Make sure that ARG is not a variable-sized array. (Note
10041 that were talking about variable-sized arrays (like
10042 `int[n]'), rather than arrays of unknown size (like
10043 `int[]').) We'll get very confused by such a type since
10044 the bound of the array will not be computable in an
10045 instantiation. Besides, such types are not allowed in
10046 ISO C++, so we can do as we please here. */
10047 if (variably_modified_type_p (arg, NULL_TREE))
10051 TREE_VEC_ELT (targs, idx) = arg;
10054 case TEMPLATE_PARM_INDEX:
10055 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10057 if (TEMPLATE_PARM_LEVEL (parm)
10058 != template_decl_level (tparm))
10059 /* The PARM is not one we're trying to unify. Just check
10060 to see if it matches ARG. */
10061 return !(TREE_CODE (arg) == TREE_CODE (parm)
10062 && cp_tree_equal (parm, arg));
10064 idx = TEMPLATE_PARM_IDX (parm);
10065 targ = TREE_VEC_ELT (targs, idx);
10068 return !cp_tree_equal (targ, arg);
10070 /* [temp.deduct.type] If, in the declaration of a function template
10071 with a non-type template-parameter, the non-type
10072 template-parameter is used in an expression in the function
10073 parameter-list and, if the corresponding template-argument is
10074 deduced, the template-argument type shall match the type of the
10075 template-parameter exactly, except that a template-argument
10076 deduced from an array bound may be of any integral type.
10077 The non-type parameter might use already deduced type parameters. */
10078 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10079 if (!TREE_TYPE (arg))
10080 /* Template-parameter dependent expression. Just accept it for now.
10081 It will later be processed in convert_template_argument. */
10083 else if (same_type_p (TREE_TYPE (arg), tparm))
10085 else if ((strict & UNIFY_ALLOW_INTEGER)
10086 && (TREE_CODE (tparm) == INTEGER_TYPE
10087 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10088 /* Convert the ARG to the type of PARM; the deduced non-type
10089 template argument must exactly match the types of the
10090 corresponding parameter. */
10091 arg = fold (build_nop (TREE_TYPE (parm), arg));
10092 else if (uses_template_parms (tparm))
10093 /* We haven't deduced the type of this parameter yet. Try again
10099 TREE_VEC_ELT (targs, idx) = arg;
10104 /* A pointer-to-member constant can be unified only with
10105 another constant. */
10106 if (TREE_CODE (arg) != PTRMEM_CST)
10109 /* Just unify the class member. It would be useless (and possibly
10110 wrong, depending on the strict flags) to unify also
10111 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10112 arg refer to the same variable, even if through different
10113 classes. For instance:
10115 struct A { int x; };
10118 Unification of &A::x and &B::x must succeed. */
10119 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10120 PTRMEM_CST_MEMBER (arg), strict);
10125 if (TREE_CODE (arg) != POINTER_TYPE)
10128 /* [temp.deduct.call]
10130 A can be another pointer or pointer to member type that can
10131 be converted to the deduced A via a qualification
10132 conversion (_conv.qual_).
10134 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10135 This will allow for additional cv-qualification of the
10136 pointed-to types if appropriate. */
10138 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10139 /* The derived-to-base conversion only persists through one
10140 level of pointers. */
10141 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10143 return unify (tparms, targs, TREE_TYPE (parm),
10144 TREE_TYPE (arg), strict);
10147 case REFERENCE_TYPE:
10148 if (TREE_CODE (arg) != REFERENCE_TYPE)
10150 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10151 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10154 if (TREE_CODE (arg) != ARRAY_TYPE)
10156 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10157 != (TYPE_DOMAIN (arg) == NULL_TREE))
10159 if (TYPE_DOMAIN (parm) != NULL_TREE)
10164 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10165 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10167 /* Our representation of array types uses "N - 1" as the
10168 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10169 not an integer constant. */
10170 if (TREE_CODE (parm_max) == MINUS_EXPR)
10172 arg_max = fold (build2 (PLUS_EXPR,
10175 TREE_OPERAND (parm_max, 1)));
10176 parm_max = TREE_OPERAND (parm_max, 0);
10179 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10182 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10183 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10190 case ENUMERAL_TYPE:
10192 if (TREE_CODE (arg) != TREE_CODE (parm))
10195 /* We have already checked cv-qualification at the top of the
10197 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10200 /* As far as unification is concerned, this wins. Later checks
10201 will invalidate it if necessary. */
10204 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10205 /* Type INTEGER_CST can come from ordinary constant template args. */
10207 while (TREE_CODE (arg) == NOP_EXPR)
10208 arg = TREE_OPERAND (arg, 0);
10210 if (TREE_CODE (arg) != INTEGER_CST)
10212 return !tree_int_cst_equal (parm, arg);
10217 if (TREE_CODE (arg) != TREE_VEC)
10219 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10221 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10222 if (unify (tparms, targs,
10223 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10231 if (TREE_CODE (arg) != TREE_CODE (parm))
10234 if (TYPE_PTRMEMFUNC_P (parm))
10236 if (!TYPE_PTRMEMFUNC_P (arg))
10239 return unify (tparms, targs,
10240 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10241 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10245 if (CLASSTYPE_TEMPLATE_INFO (parm))
10247 tree t = NULL_TREE;
10249 if (strict_in & UNIFY_ALLOW_DERIVED)
10251 /* First, we try to unify the PARM and ARG directly. */
10252 t = try_class_unification (tparms, targs,
10257 /* Fallback to the special case allowed in
10258 [temp.deduct.call]:
10260 If P is a class, and P has the form
10261 template-id, then A can be a derived class of
10262 the deduced A. Likewise, if P is a pointer to
10263 a class of the form template-id, A can be a
10264 pointer to a derived class pointed to by the
10266 t = get_template_base (tparms, targs, parm, arg);
10272 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10273 && (CLASSTYPE_TI_TEMPLATE (parm)
10274 == CLASSTYPE_TI_TEMPLATE (arg)))
10275 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10276 Then, we should unify `int' and `U'. */
10279 /* There's no chance of unification succeeding. */
10282 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10283 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10285 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10290 case FUNCTION_TYPE:
10291 if (TREE_CODE (arg) != TREE_CODE (parm))
10294 if (unify (tparms, targs, TREE_TYPE (parm),
10295 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10297 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10298 TYPE_ARG_TYPES (arg), 1,
10299 DEDUCE_EXACT, 0, -1);
10302 if (TREE_CODE (arg) != OFFSET_TYPE)
10304 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10305 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10307 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10311 if (DECL_TEMPLATE_PARM_P (parm))
10312 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10313 if (arg != integral_constant_value (parm))
10318 case TEMPLATE_DECL:
10319 /* Matched cases are handled by the ARG == PARM test above. */
10323 gcc_assert (EXPR_P (parm));
10325 /* We must be looking at an expression. This can happen with
10329 void foo(S<I>, S<I + 2>);
10331 This is a "nondeduced context":
10335 The nondeduced contexts are:
10337 --A type that is a template-id in which one or more of
10338 the template-arguments is an expression that references
10339 a template-parameter.
10341 In these cases, we assume deduction succeeded, but don't
10342 actually infer any unifications. */
10344 if (!uses_template_parms (parm)
10345 && !template_args_equal (parm, arg))
10352 /* Note that DECL can be defined in this translation unit, if
10356 mark_definable (tree decl)
10359 DECL_NOT_REALLY_EXTERN (decl) = 1;
10360 FOR_EACH_CLONE (clone, decl)
10361 DECL_NOT_REALLY_EXTERN (clone) = 1;
10364 /* Called if RESULT is explicitly instantiated, or is a member of an
10365 explicitly instantiated class. */
10368 mark_decl_instantiated (tree result, int extern_p)
10370 SET_DECL_EXPLICIT_INSTANTIATION (result);
10372 /* If this entity has already been written out, it's too late to
10373 make any modifications. */
10374 if (TREE_ASM_WRITTEN (result))
10377 if (TREE_CODE (result) != FUNCTION_DECL)
10378 /* The TREE_PUBLIC flag for function declarations will have been
10379 set correctly by tsubst. */
10380 TREE_PUBLIC (result) = 1;
10382 /* This might have been set by an earlier implicit instantiation. */
10383 DECL_COMDAT (result) = 0;
10386 DECL_NOT_REALLY_EXTERN (result) = 0;
10389 mark_definable (result);
10390 /* Always make artificials weak. */
10391 if (DECL_ARTIFICIAL (result) && flag_weak)
10392 comdat_linkage (result);
10393 /* For WIN32 we also want to put explicit instantiations in
10394 linkonce sections. */
10395 else if (TREE_PUBLIC (result))
10396 maybe_make_one_only (result);
10399 /* If EXTERN_P, then this function will not be emitted -- unless
10400 followed by an explicit instantiation, at which point its linkage
10401 will be adjusted. If !EXTERN_P, then this function will be
10402 emitted here. In neither circumstance do we want
10403 import_export_decl to adjust the linkage. */
10404 DECL_INTERFACE_KNOWN (result) = 1;
10407 /* Given two function templates PAT1 and PAT2, return:
10409 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
10411 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10412 -1 if PAT2 is more specialized than PAT1.
10413 0 if neither is more specialized.
10415 LEN is passed through to fn_type_unification. */
10418 more_specialized (tree pat1, tree pat2, int deduce, int len)
10423 /* If template argument deduction succeeds, we substitute the
10424 resulting arguments into non-deduced contexts. While doing that,
10425 we must be aware that we may encounter dependent types. */
10426 ++processing_template_decl;
10427 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
10428 NULL_TREE, 0, deduce, len);
10432 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
10433 NULL_TREE, 0, deduce, len);
10436 --processing_template_decl;
10441 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10443 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10444 -1 if PAT2 is more specialized than PAT1.
10445 0 if neither is more specialized.
10447 FULL_ARGS is the full set of template arguments that triggers this
10448 partial ordering. */
10451 more_specialized_class (tree pat1, tree pat2, tree full_args)
10456 /* Just like what happens for functions, if we are ordering between
10457 different class template specializations, we may encounter dependent
10458 types in the arguments, and we need our dependency check functions
10459 to behave correctly. */
10460 ++processing_template_decl;
10461 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10462 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10466 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10467 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10470 --processing_template_decl;
10475 /* Return the template arguments that will produce the function signature
10476 DECL from the function template FN, with the explicit template
10477 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
10478 also match. Return NULL_TREE if no satisfactory arguments could be
10479 found. DEDUCE and LEN are passed through to fn_type_unification. */
10482 get_bindings_real (tree fn,
10484 tree explicit_args,
10489 int ntparms = DECL_NTPARMS (fn);
10490 tree targs = make_tree_vec (ntparms);
10492 tree decl_arg_types;
10495 /* Substitute the explicit template arguments into the type of DECL.
10496 The call to fn_type_unification will handle substitution into the
10498 decl_type = TREE_TYPE (decl);
10499 if (explicit_args && uses_template_parms (decl_type))
10502 tree converted_args;
10504 if (DECL_TEMPLATE_INFO (decl))
10505 tmpl = DECL_TI_TEMPLATE (decl);
10507 /* We can get here for some invalid specializations. */
10511 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10512 explicit_args, NULL_TREE,
10513 tf_none, /*require_all_arguments=*/0));
10514 if (converted_args == error_mark_node)
10517 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10518 if (decl_type == error_mark_node)
10522 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10523 /* Never do unification on the 'this' parameter. */
10524 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10525 decl_arg_types = TREE_CHAIN (decl_arg_types);
10527 i = fn_type_unification (fn, explicit_args, targs,
10529 (check_rettype || DECL_CONV_FN_P (fn)
10530 ? TREE_TYPE (decl_type) : NULL_TREE),
10539 /* For most uses, we want to check the return type. */
10542 get_bindings (tree fn, tree decl, tree explicit_args)
10544 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10547 /* But for resolve_overloaded_unification, we only care about the parameter
10551 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10553 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10556 /* Return the innermost template arguments that, when applied to a
10557 template specialization whose innermost template parameters are
10558 TPARMS, and whose specialization arguments are PARMS, yield the
10561 For example, suppose we have:
10563 template <class T, class U> struct S {};
10564 template <class T> struct S<T*, int> {};
10566 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10567 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10568 int}. The resulting vector will be {double}, indicating that `T'
10569 is bound to `double'. */
10572 get_class_bindings (tree tparms, tree parms, tree args)
10574 int i, ntparms = TREE_VEC_LENGTH (tparms);
10575 tree vec = make_tree_vec (ntparms);
10577 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10581 for (i = 0; i < ntparms; ++i)
10582 if (! TREE_VEC_ELT (vec, i))
10585 if (verify_class_unification (vec, parms, args))
10591 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10592 Pick the most specialized template, and return the corresponding
10593 instantiation, or if there is no corresponding instantiation, the
10594 template itself. If there is no most specialized template,
10595 error_mark_node is returned. If there are no templates at all,
10596 NULL_TREE is returned. */
10599 most_specialized_instantiation (tree instantiations)
10604 if (!instantiations)
10607 champ = instantiations;
10608 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10610 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10618 fn = TREE_CHAIN (fn);
10620 return error_mark_node;
10626 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10628 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10631 return error_mark_node;
10634 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10637 /* Return the most specialized of the list of templates in FNS that can
10638 produce an instantiation matching DECL, given the explicit template
10639 arguments EXPLICIT_ARGS. */
10642 most_specialized (tree fns, tree decl, tree explicit_args)
10644 tree candidates = NULL_TREE;
10647 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10649 tree candidate = TREE_VALUE (fn);
10651 args = get_bindings (candidate, decl, explicit_args);
10653 candidates = tree_cons (NULL_TREE, candidate, candidates);
10656 return most_specialized_instantiation (candidates);
10659 /* If DECL is a specialization of some template, return the most
10660 general such template. Otherwise, returns NULL_TREE.
10662 For example, given:
10664 template <class T> struct S { template <class U> void f(U); };
10666 if TMPL is `template <class U> void S<int>::f(U)' this will return
10667 the full template. This function will not trace past partial
10668 specializations, however. For example, given in addition:
10670 template <class T> struct S<T*> { template <class U> void f(U); };
10672 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10673 `template <class T> template <class U> S<T*>::f(U)'. */
10676 most_general_template (tree decl)
10678 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10679 an immediate specialization. */
10680 if (TREE_CODE (decl) == FUNCTION_DECL)
10682 if (DECL_TEMPLATE_INFO (decl)) {
10683 decl = DECL_TI_TEMPLATE (decl);
10685 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10686 template friend. */
10687 if (TREE_CODE (decl) != TEMPLATE_DECL)
10693 /* Look for more and more general templates. */
10694 while (DECL_TEMPLATE_INFO (decl))
10696 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10697 (See cp-tree.h for details.) */
10698 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10701 if (CLASS_TYPE_P (TREE_TYPE (decl))
10702 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10705 /* Stop if we run into an explicitly specialized class template. */
10706 if (!DECL_NAMESPACE_SCOPE_P (decl)
10707 && DECL_CONTEXT (decl)
10708 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10711 decl = DECL_TI_TEMPLATE (decl);
10717 /* Return the most specialized of the class template specializations
10718 of TMPL which can produce an instantiation matching ARGS, or
10719 error_mark_node if the choice is ambiguous. */
10722 most_specialized_class (tree tmpl, tree args)
10724 tree list = NULL_TREE;
10729 tmpl = most_general_template (tmpl);
10730 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10733 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10736 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10737 TREE_TYPE (list) = TREE_TYPE (t);
10746 t = TREE_CHAIN (t);
10747 for (; t; t = TREE_CHAIN (t))
10749 fate = more_specialized_class (champ, t, args);
10756 t = TREE_CHAIN (t);
10758 return error_mark_node;
10764 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10766 fate = more_specialized_class (champ, t, args);
10768 return error_mark_node;
10774 /* Explicitly instantiate DECL. */
10777 do_decl_instantiation (tree decl, tree storage)
10779 tree result = NULL_TREE;
10783 /* An error occurred, for which grokdeclarator has already issued
10784 an appropriate message. */
10786 else if (! DECL_LANG_SPECIFIC (decl))
10788 error ("explicit instantiation of non-template %q#D", decl);
10791 else if (TREE_CODE (decl) == VAR_DECL)
10793 /* There is an asymmetry here in the way VAR_DECLs and
10794 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10795 the latter, the DECL we get back will be marked as a
10796 template instantiation, and the appropriate
10797 DECL_TEMPLATE_INFO will be set up. This does not happen for
10798 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10799 should handle VAR_DECLs as it currently handles
10801 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10802 if (!result || TREE_CODE (result) != VAR_DECL)
10804 error ("no matching template for %qD found", decl);
10808 else if (TREE_CODE (decl) != FUNCTION_DECL)
10810 error ("explicit instantiation of %q#D", decl);
10816 /* Check for various error cases. Note that if the explicit
10817 instantiation is valid the RESULT will currently be marked as an
10818 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10819 until we get here. */
10821 if (DECL_TEMPLATE_SPECIALIZATION (result))
10823 /* DR 259 [temp.spec].
10825 Both an explicit instantiation and a declaration of an explicit
10826 specialization shall not appear in a program unless the explicit
10827 instantiation follows a declaration of the explicit specialization.
10829 For a given set of template parameters, if an explicit
10830 instantiation of a template appears after a declaration of an
10831 explicit specialization for that template, the explicit
10832 instantiation has no effect. */
10835 else if (DECL_EXPLICIT_INSTANTIATION (result))
10839 No program shall explicitly instantiate any template more
10842 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10843 the first instantiation was `extern' and the second is not,
10844 and EXTERN_P for the opposite case. */
10845 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10846 pedwarn ("duplicate explicit instantiation of %q#D", result);
10847 /* If an "extern" explicit instantiation follows an ordinary
10848 explicit instantiation, the template is instantiated. */
10852 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10854 error ("no matching template for %qD found", result);
10857 else if (!DECL_TEMPLATE_INFO (result))
10859 pedwarn ("explicit instantiation of non-template %q#D", result);
10863 if (storage == NULL_TREE)
10865 else if (storage == ridpointers[(int) RID_EXTERN])
10867 if (pedantic && !in_system_header)
10868 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
10873 error ("storage class %qD applied to template instantiation", storage);
10875 mark_decl_instantiated (result, extern_p);
10877 instantiate_decl (result, /*defer_ok=*/1, /*undefined_ok=*/0);
10881 mark_class_instantiated (tree t, int extern_p)
10883 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10884 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10885 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10886 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10889 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10890 rest_of_type_compilation (t, 1);
10894 /* Called from do_type_instantiation through binding_table_foreach to
10895 do recursive instantiation for the type bound in ENTRY. */
10897 bt_instantiate_type_proc (binding_entry entry, void *data)
10899 tree storage = *(tree *) data;
10901 if (IS_AGGR_TYPE (entry->type)
10902 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10903 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10906 /* Called from do_type_instantiation to instantiate a member
10907 (a member function or a static member variable) of an
10908 explicitly instantiated class template. */
10910 instantiate_class_member (tree decl, int extern_p)
10912 mark_decl_instantiated (decl, extern_p);
10914 instantiate_decl (decl, /*defer_ok=*/1, /* undefined_ok=*/1);
10917 /* Perform an explicit instantiation of template class T. STORAGE, if
10918 non-null, is the RID for extern, inline or static. COMPLAIN is
10919 nonzero if this is called from the parser, zero if called recursively,
10920 since the standard is unclear (as detailed below). */
10923 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10928 int previous_instantiation_extern_p = 0;
10930 if (TREE_CODE (t) == TYPE_DECL)
10933 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10935 error ("explicit instantiation of non-template type %qT", t);
10941 if (!COMPLETE_TYPE_P (t))
10943 if (complain & tf_error)
10944 error ("explicit instantiation of %q#T before definition of template",
10949 if (storage != NULL_TREE)
10951 if (pedantic && !in_system_header)
10952 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
10955 if (storage == ridpointers[(int) RID_INLINE])
10957 else if (storage == ridpointers[(int) RID_EXTERN])
10959 else if (storage == ridpointers[(int) RID_STATIC])
10963 error ("storage class %qD applied to template instantiation",
10969 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10971 /* DR 259 [temp.spec].
10973 Both an explicit instantiation and a declaration of an explicit
10974 specialization shall not appear in a program unless the explicit
10975 instantiation follows a declaration of the explicit specialization.
10977 For a given set of template parameters, if an explicit
10978 instantiation of a template appears after a declaration of an
10979 explicit specialization for that template, the explicit
10980 instantiation has no effect. */
10983 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10987 No program shall explicitly instantiate any template more
10990 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
10991 instantiation was `extern'. If EXTERN_P then the second is.
10992 These cases are OK. */
10993 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
10995 if (!previous_instantiation_extern_p && !extern_p
10996 && (complain & tf_error))
10997 pedwarn ("duplicate explicit instantiation of %q#T", t);
10999 /* If we've already instantiated the template, just return now. */
11000 if (!CLASSTYPE_INTERFACE_ONLY (t))
11004 mark_class_instantiated (t, extern_p);
11012 /* In contrast to implicit instantiation, where only the
11013 declarations, and not the definitions, of members are
11014 instantiated, we have here:
11018 The explicit instantiation of a class template specialization
11019 implies the instantiation of all of its members not
11020 previously explicitly specialized in the translation unit
11021 containing the explicit instantiation.
11023 Of course, we can't instantiate member template classes, since
11024 we don't have any arguments for them. Note that the standard
11025 is unclear on whether the instantiation of the members are
11026 *explicit* instantiations or not. However, the most natural
11027 interpretation is that it should be an explicit instantiation. */
11030 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11031 if (TREE_CODE (tmp) == FUNCTION_DECL
11032 && DECL_TEMPLATE_INSTANTIATION (tmp))
11033 instantiate_class_member (tmp, extern_p);
11035 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11036 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11037 instantiate_class_member (tmp, extern_p);
11039 if (CLASSTYPE_NESTED_UTDS (t))
11040 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11041 bt_instantiate_type_proc, &storage);
11045 /* Given a function DECL, which is a specialization of TMPL, modify
11046 DECL to be a re-instantiation of TMPL with the same template
11047 arguments. TMPL should be the template into which tsubst'ing
11048 should occur for DECL, not the most general template.
11050 One reason for doing this is a scenario like this:
11053 void f(const T&, int i);
11055 void g() { f(3, 7); }
11058 void f(const T& t, const int i) { }
11060 Note that when the template is first instantiated, with
11061 instantiate_template, the resulting DECL will have no name for the
11062 first parameter, and the wrong type for the second. So, when we go
11063 to instantiate the DECL, we regenerate it. */
11066 regenerate_decl_from_template (tree decl, tree tmpl)
11068 /* The arguments used to instantiate DECL, from the most general
11073 args = DECL_TI_ARGS (decl);
11074 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11076 /* Make sure that we can see identifiers, and compute access
11078 push_access_scope (decl);
11080 if (TREE_CODE (decl) == FUNCTION_DECL)
11088 args_depth = TMPL_ARGS_DEPTH (args);
11089 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11090 if (args_depth > parms_depth)
11091 args = get_innermost_template_args (args, parms_depth);
11093 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11094 args, tf_error, NULL_TREE);
11096 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11099 /* Merge parameter declarations. */
11100 decl_parm = skip_artificial_parms_for (decl,
11101 DECL_ARGUMENTS (decl));
11103 = skip_artificial_parms_for (code_pattern,
11104 DECL_ARGUMENTS (code_pattern));
11109 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11110 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11111 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11113 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11114 TREE_TYPE (decl_parm) = parm_type;
11115 decl_parm = TREE_CHAIN (decl_parm);
11116 pattern_parm = TREE_CHAIN (pattern_parm);
11119 /* Merge additional specifiers from the CODE_PATTERN. */
11120 if (DECL_DECLARED_INLINE_P (code_pattern)
11121 && !DECL_DECLARED_INLINE_P (decl))
11122 DECL_DECLARED_INLINE_P (decl) = 1;
11123 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11124 DECL_INLINE (decl) = 1;
11126 else if (TREE_CODE (decl) == VAR_DECL)
11128 if (!DECL_INITIALIZED_IN_CLASS_P (decl)
11129 && DECL_INITIAL (code_pattern))
11130 DECL_INITIAL (decl) =
11131 tsubst_expr (DECL_INITIAL (code_pattern), args,
11132 tf_error, DECL_TI_TEMPLATE (decl));
11135 gcc_unreachable ();
11137 pop_access_scope (decl);
11140 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11141 substituted to get DECL. */
11144 template_for_substitution (tree decl)
11146 tree tmpl = DECL_TI_TEMPLATE (decl);
11148 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11149 for the instantiation. This is not always the most general
11150 template. Consider, for example:
11153 struct S { template <class U> void f();
11154 template <> void f<int>(); };
11156 and an instantiation of S<double>::f<int>. We want TD to be the
11157 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11158 while (/* An instantiation cannot have a definition, so we need a
11159 more general template. */
11160 DECL_TEMPLATE_INSTANTIATION (tmpl)
11161 /* We must also deal with friend templates. Given:
11163 template <class T> struct S {
11164 template <class U> friend void f() {};
11167 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11168 so far as the language is concerned, but that's still
11169 where we get the pattern for the instantiation from. On
11170 other hand, if the definition comes outside the class, say:
11172 template <class T> struct S {
11173 template <class U> friend void f();
11175 template <class U> friend void f() {}
11177 we don't need to look any further. That's what the check for
11178 DECL_INITIAL is for. */
11179 || (TREE_CODE (decl) == FUNCTION_DECL
11180 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11181 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11183 /* The present template, TD, should not be a definition. If it
11184 were a definition, we should be using it! Note that we
11185 cannot restructure the loop to just keep going until we find
11186 a template with a definition, since that might go too far if
11187 a specialization was declared, but not defined. */
11188 gcc_assert (TREE_CODE (decl) != VAR_DECL
11189 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11191 /* Fetch the more general template. */
11192 tmpl = DECL_TI_TEMPLATE (tmpl);
11198 /* Produce the definition of D, a _DECL generated from a template. If
11199 DEFER_OK is nonzero, then we don't have to actually do the
11200 instantiation now; we just have to do it sometime. Normally it is
11201 an error if this is an explicit instantiation but D is undefined.
11202 If UNDEFINED_OK is nonzero, then instead we treat it as an implicit
11203 instantiation. UNDEFINED_OK is nonzero only if we are being used
11204 to instantiate the members of an explicitly instantiated class
11209 instantiate_decl (tree d, int defer_ok, int undefined_ok)
11211 tree tmpl = DECL_TI_TEMPLATE (d);
11218 int pattern_defined;
11220 location_t saved_loc = input_location;
11222 /* This function should only be used to instantiate templates for
11223 functions and static member variables. */
11224 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11225 || TREE_CODE (d) == VAR_DECL);
11227 /* Variables are never deferred; if instantiation is required, they
11228 are instantiated right away. That allows for better code in the
11229 case that an expression refers to the value of the variable --
11230 if the variable has a constant value the referring expression can
11231 take advantage of that fact. */
11232 if (TREE_CODE (d) == VAR_DECL)
11235 /* Don't instantiate cloned functions. Instead, instantiate the
11236 functions they cloned. */
11237 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11238 d = DECL_CLONED_FUNCTION (d);
11240 if (DECL_TEMPLATE_INSTANTIATED (d))
11241 /* D has already been instantiated. It might seem reasonable to
11242 check whether or not D is an explicit instantiation, and, if so,
11243 stop here. But when an explicit instantiation is deferred
11244 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11245 is set, even though we still need to do the instantiation. */
11248 /* If we already have a specialization of this declaration, then
11249 there's no reason to instantiate it. Note that
11250 retrieve_specialization gives us both instantiations and
11251 specializations, so we must explicitly check
11252 DECL_TEMPLATE_SPECIALIZATION. */
11253 gen_tmpl = most_general_template (tmpl);
11254 gen_args = DECL_TI_ARGS (d);
11255 spec = retrieve_specialization (gen_tmpl, gen_args,
11256 /*class_specializations_p=*/false);
11257 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11260 /* This needs to happen before any tsubsting. */
11261 if (! push_tinst_level (d))
11264 timevar_push (TV_PARSE);
11266 /* We may be in the middle of deferred access check. Disable it now. */
11267 push_deferring_access_checks (dk_no_deferred);
11269 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11270 for the instantiation. */
11271 td = template_for_substitution (d);
11272 code_pattern = DECL_TEMPLATE_RESULT (td);
11274 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11275 || DECL_TEMPLATE_SPECIALIZATION (td))
11276 /* In the case of a friend template whose definition is provided
11277 outside the class, we may have too many arguments. Drop the
11278 ones we don't need. The same is true for specializations. */
11279 args = get_innermost_template_args
11280 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11284 if (TREE_CODE (d) == FUNCTION_DECL)
11285 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11287 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11288 /* Unless an explicit instantiation directive has already determined
11289 the linkage of D, remember that a definition is available for
11291 if (pattern_defined
11292 && !DECL_INTERFACE_KNOWN (d)
11293 && !DECL_NOT_REALLY_EXTERN (d))
11294 mark_definable (d);
11296 input_location = DECL_SOURCE_LOCATION (d);
11298 if (! pattern_defined && DECL_EXPLICIT_INSTANTIATION (d) && undefined_ok)
11300 DECL_NOT_REALLY_EXTERN (d) = 0;
11301 SET_DECL_IMPLICIT_INSTANTIATION (d);
11306 /* Recheck the substitutions to obtain any warning messages
11307 about ignoring cv qualifiers. */
11308 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11309 tree type = TREE_TYPE (gen);
11311 /* Make sure that we can see identifiers, and compute access
11312 correctly. D is already the target FUNCTION_DECL with the
11314 push_access_scope (d);
11316 if (TREE_CODE (gen) == FUNCTION_DECL)
11318 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11319 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11320 tf_error | tf_warning, d);
11321 /* Don't simply tsubst the function type, as that will give
11322 duplicate warnings about poor parameter qualifications.
11323 The function arguments are the same as the decl_arguments
11324 without the top level cv qualifiers. */
11325 type = TREE_TYPE (type);
11327 tsubst (type, gen_args, tf_error | tf_warning, d);
11329 pop_access_scope (d);
11332 /* We should have set up DECL_INITIAL in instantiate_class_template
11333 for in-class definitions of static data members. */
11334 gcc_assert (!(TREE_CODE (d) == VAR_DECL
11335 && DECL_INITIALIZED_IN_CLASS_P (d)
11336 && DECL_INITIAL (d) == NULL_TREE));
11338 /* Do not instantiate templates that we know will be defined
11340 if (DECL_INTERFACE_KNOWN (d)
11341 && DECL_REALLY_EXTERN (d)
11342 && ! (TREE_CODE (d) == FUNCTION_DECL
11343 && DECL_INLINE (d)))
11345 /* Defer all other templates, unless we have been explicitly
11346 forbidden from doing so. We restore the source position here
11347 because it's used by add_pending_template. */
11348 else if (! pattern_defined || defer_ok)
11350 input_location = saved_loc;
11352 if (at_eof && !pattern_defined
11353 && DECL_EXPLICIT_INSTANTIATION (d))
11356 The definition of a non-exported function template, a
11357 non-exported member function template, or a non-exported
11358 member function or static data member of a class template
11359 shall be present in every translation unit in which it is
11360 explicitly instantiated. */
11362 ("explicit instantiation of %qD but no definition available", d);
11364 add_pending_template (d);
11367 /* Tell the repository that D is available in this translation unit
11368 -- and see if it is supposed to be instantiated here. */
11369 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11371 /* In a PCH file, despite the fact that the repository hasn't
11372 requested instantiation in the PCH it is still possible that
11373 an instantiation will be required in a file that includes the
11376 add_pending_template (d);
11377 /* Instantiate inline functions so that the inliner can do its
11378 job, even though we'll not be emitting a copy of this
11380 if (!(TREE_CODE (d) == FUNCTION_DECL
11381 && flag_inline_trees
11382 && DECL_DECLARED_INLINE_P (d)))
11386 need_push = !cfun || !global_bindings_p ();
11388 push_to_top_level ();
11390 /* Mark D as instantiated so that recursive calls to
11391 instantiate_decl do not try to instantiate it again. */
11392 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11394 /* Regenerate the declaration in case the template has been modified
11395 by a subsequent redeclaration. */
11396 regenerate_decl_from_template (d, td);
11398 /* We already set the file and line above. Reset them now in case
11399 they changed as a result of calling regenerate_decl_from_template. */
11400 input_location = DECL_SOURCE_LOCATION (d);
11402 if (TREE_CODE (d) == VAR_DECL)
11404 /* Clear out DECL_RTL; whatever was there before may not be right
11405 since we've reset the type of the declaration. */
11406 SET_DECL_RTL (d, NULL_RTX);
11407 DECL_IN_AGGR_P (d) = 0;
11409 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11410 initializer. That function will defer actual emission until
11411 we have a chance to determine linkage. */
11412 DECL_EXTERNAL (d) = 0;
11414 /* Enter the scope of D so that access-checking works correctly. */
11415 push_nested_class (DECL_CONTEXT (d));
11417 (!DECL_INITIALIZED_IN_CLASS_P (d)
11418 ? DECL_INITIAL (d) : NULL_TREE),
11420 pop_nested_class ();
11422 else if (TREE_CODE (d) == FUNCTION_DECL)
11424 htab_t saved_local_specializations;
11429 /* Save away the current list, in case we are instantiating one
11430 template from within the body of another. */
11431 saved_local_specializations = local_specializations;
11433 /* Set up the list of local specializations. */
11434 local_specializations = htab_create (37,
11435 hash_local_specialization,
11436 eq_local_specializations,
11439 /* Set up context. */
11440 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11442 /* Create substitution entries for the parameters. */
11443 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11444 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11445 spec_parm = DECL_ARGUMENTS (d);
11446 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11448 register_local_specialization (spec_parm, tmpl_parm);
11449 spec_parm = skip_artificial_parms_for (d, spec_parm);
11450 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11454 register_local_specialization (spec_parm, tmpl_parm);
11455 tmpl_parm = TREE_CHAIN (tmpl_parm);
11456 spec_parm = TREE_CHAIN (spec_parm);
11458 gcc_assert (!spec_parm);
11460 /* Substitute into the body of the function. */
11461 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11462 tf_error | tf_warning, tmpl);
11464 /* We don't need the local specializations any more. */
11465 htab_delete (local_specializations);
11466 local_specializations = saved_local_specializations;
11468 /* Finish the function. */
11469 d = finish_function (0);
11470 expand_or_defer_fn (d);
11473 /* We're not deferring instantiation any more. */
11474 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11477 pop_from_top_level ();
11480 input_location = saved_loc;
11481 pop_deferring_access_checks ();
11482 pop_tinst_level ();
11484 timevar_pop (TV_PARSE);
11489 /* Run through the list of templates that we wish we could
11490 instantiate, and instantiate any we can. RETRIES is the
11491 number of times we retry pending template instantiation. */
11494 instantiate_pending_templates (int retries)
11497 tree last = NULL_TREE;
11499 location_t saved_loc = input_location;
11501 /* Instantiating templates may trigger vtable generation. This in turn
11502 may require further template instantiations. We place a limit here
11503 to avoid infinite loop. */
11504 if (pending_templates && retries >= max_tinst_depth)
11506 cp_error_at ("template instantiation depth exceeds maximum of %d"
11507 " (use -ftemplate-depth-NN to increase the maximum)"
11508 " instantiating %q+D, possibly from virtual table"
11510 max_tinst_depth, TREE_VALUE (pending_templates));
11518 t = &pending_templates;
11521 tree instantiation = TREE_VALUE (*t);
11523 reopen_tinst_level (TREE_PURPOSE (*t));
11525 if (TYPE_P (instantiation))
11529 if (!COMPLETE_TYPE_P (instantiation))
11531 instantiate_class_template (instantiation);
11532 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11533 for (fn = TYPE_METHODS (instantiation);
11535 fn = TREE_CHAIN (fn))
11536 if (! DECL_ARTIFICIAL (fn))
11537 instantiate_decl (fn, /*defer_ok=*/0,
11538 /*undefined_ok=*/0);
11539 if (COMPLETE_TYPE_P (instantiation))
11543 if (COMPLETE_TYPE_P (instantiation))
11544 /* If INSTANTIATION has been instantiated, then we don't
11545 need to consider it again in the future. */
11546 *t = TREE_CHAIN (*t);
11550 t = &TREE_CHAIN (*t);
11555 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11556 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11558 instantiation = instantiate_decl (instantiation,
11560 /*undefined_ok=*/0);
11561 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11565 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11566 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11567 /* If INSTANTIATION has been instantiated, then we don't
11568 need to consider it again in the future. */
11569 *t = TREE_CHAIN (*t);
11573 t = &TREE_CHAIN (*t);
11577 current_tinst_level = NULL_TREE;
11579 last_pending_template = last;
11581 while (reconsider);
11583 input_location = saved_loc;
11586 /* Substitute ARGVEC into T, which is a list of initializers for
11587 either base class or a non-static data member. The TREE_PURPOSEs
11588 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11589 instantiate_decl. */
11592 tsubst_initializer_list (tree t, tree argvec)
11594 tree inits = NULL_TREE;
11596 for (; t; t = TREE_CHAIN (t))
11601 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11603 decl = expand_member_init (decl);
11604 if (decl && !DECL_P (decl))
11605 in_base_initializer = 1;
11607 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11609 in_base_initializer = 0;
11613 init = build_tree_list (decl, init);
11614 TREE_CHAIN (init) = inits;
11621 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11624 set_current_access_from_decl (tree decl)
11626 if (TREE_PRIVATE (decl))
11627 current_access_specifier = access_private_node;
11628 else if (TREE_PROTECTED (decl))
11629 current_access_specifier = access_protected_node;
11631 current_access_specifier = access_public_node;
11634 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11635 is the instantiation (which should have been created with
11636 start_enum) and ARGS are the template arguments to use. */
11639 tsubst_enum (tree tag, tree newtag, tree args)
11643 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11648 decl = TREE_VALUE (e);
11649 /* Note that in a template enum, the TREE_VALUE is the
11650 CONST_DECL, not the corresponding INTEGER_CST. */
11651 value = tsubst_expr (DECL_INITIAL (decl),
11652 args, tf_error | tf_warning,
11655 /* Give this enumeration constant the correct access. */
11656 set_current_access_from_decl (decl);
11658 /* Actually build the enumerator itself. */
11659 build_enumerator (DECL_NAME (decl), value, newtag);
11662 finish_enum (newtag);
11663 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11664 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11667 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11668 its type -- but without substituting the innermost set of template
11669 arguments. So, innermost set of template parameters will appear in
11673 get_mostly_instantiated_function_type (tree decl)
11681 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11682 targs = DECL_TI_ARGS (decl);
11683 tparms = DECL_TEMPLATE_PARMS (tmpl);
11684 parm_depth = TMPL_PARMS_DEPTH (tparms);
11686 /* There should be as many levels of arguments as there are levels
11688 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11690 fn_type = TREE_TYPE (tmpl);
11692 if (parm_depth == 1)
11693 /* No substitution is necessary. */
11700 /* Replace the innermost level of the TARGS with NULL_TREEs to
11701 let tsubst know not to substitute for those parameters. */
11702 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11703 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11704 SET_TMPL_ARGS_LEVEL (partial_args, i,
11705 TMPL_ARGS_LEVEL (targs, i));
11706 SET_TMPL_ARGS_LEVEL (partial_args,
11707 TMPL_ARGS_DEPTH (targs),
11708 make_tree_vec (DECL_NTPARMS (tmpl)));
11710 /* Make sure that we can see identifiers, and compute access
11711 correctly. We can just use the context of DECL for the
11712 partial substitution here. It depends only on outer template
11713 parameters, regardless of whether the innermost level is
11714 specialized or not. */
11715 push_access_scope (decl);
11717 ++processing_template_decl;
11718 /* Now, do the (partial) substitution to figure out the
11719 appropriate function type. */
11720 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11721 --processing_template_decl;
11723 /* Substitute into the template parameters to obtain the real
11724 innermost set of parameters. This step is important if the
11725 innermost set of template parameters contains value
11726 parameters whose types depend on outer template parameters. */
11727 TREE_VEC_LENGTH (partial_args)--;
11728 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11730 pop_access_scope (decl);
11736 /* Return truthvalue if we're processing a template different from
11737 the last one involved in diagnostics. */
11739 problematic_instantiation_changed (void)
11741 return last_template_error_tick != tinst_level_tick;
11744 /* Remember current template involved in diagnostics. */
11746 record_last_problematic_instantiation (void)
11748 last_template_error_tick = tinst_level_tick;
11752 current_instantiation (void)
11754 return current_tinst_level;
11757 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11758 type. Return zero for ok, nonzero for disallowed. Issue error and
11759 warning messages under control of COMPLAIN. */
11762 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11764 if (INTEGRAL_TYPE_P (type))
11766 else if (POINTER_TYPE_P (type))
11768 else if (TYPE_PTR_TO_MEMBER_P (type))
11770 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11772 else if (TREE_CODE (type) == TYPENAME_TYPE)
11775 if (complain & tf_error)
11776 error ("%q#T is not a valid type for a template constant parameter", type);
11780 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11781 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11784 dependent_type_p_r (tree type)
11790 A type is dependent if it is:
11792 -- a template parameter. Template template parameters are types
11793 for us (since TYPE_P holds true for them) so we handle
11795 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11796 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11798 /* -- a qualified-id with a nested-name-specifier which contains a
11799 class-name that names a dependent type or whose unqualified-id
11800 names a dependent type. */
11801 if (TREE_CODE (type) == TYPENAME_TYPE)
11803 /* -- a cv-qualified type where the cv-unqualified type is
11805 type = TYPE_MAIN_VARIANT (type);
11806 /* -- a compound type constructed from any dependent type. */
11807 if (TYPE_PTR_TO_MEMBER_P (type))
11808 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11809 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11811 else if (TREE_CODE (type) == POINTER_TYPE
11812 || TREE_CODE (type) == REFERENCE_TYPE)
11813 return dependent_type_p (TREE_TYPE (type));
11814 else if (TREE_CODE (type) == FUNCTION_TYPE
11815 || TREE_CODE (type) == METHOD_TYPE)
11819 if (dependent_type_p (TREE_TYPE (type)))
11821 for (arg_type = TYPE_ARG_TYPES (type);
11823 arg_type = TREE_CHAIN (arg_type))
11824 if (dependent_type_p (TREE_VALUE (arg_type)))
11828 /* -- an array type constructed from any dependent type or whose
11829 size is specified by a constant expression that is
11830 value-dependent. */
11831 if (TREE_CODE (type) == ARRAY_TYPE)
11833 if (TYPE_DOMAIN (type)
11834 && ((value_dependent_expression_p
11835 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11836 || (type_dependent_expression_p
11837 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11839 return dependent_type_p (TREE_TYPE (type));
11842 /* -- a template-id in which either the template name is a template
11844 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11846 /* ... or any of the template arguments is a dependent type or
11847 an expression that is type-dependent or value-dependent. */
11848 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11849 && (any_dependent_template_arguments_p
11850 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11853 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11854 expression is not type-dependent, then it should already been
11856 if (TREE_CODE (type) == TYPEOF_TYPE)
11859 /* The standard does not specifically mention types that are local
11860 to template functions or local classes, but they should be
11861 considered dependent too. For example:
11863 template <int I> void f() {
11868 The size of `E' cannot be known until the value of `I' has been
11869 determined. Therefore, `E' must be considered dependent. */
11870 scope = TYPE_CONTEXT (type);
11871 if (scope && TYPE_P (scope))
11872 return dependent_type_p (scope);
11873 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11874 return type_dependent_expression_p (scope);
11876 /* Other types are non-dependent. */
11880 /* Returns TRUE if TYPE is dependent, in the sense of
11881 [temp.dep.type]. */
11884 dependent_type_p (tree type)
11886 /* If there are no template parameters in scope, then there can't be
11887 any dependent types. */
11888 if (!processing_template_decl)
11891 /* If the type is NULL, we have not computed a type for the entity
11892 in question; in that case, the type is dependent. */
11896 /* Erroneous types can be considered non-dependent. */
11897 if (type == error_mark_node)
11900 /* If we have not already computed the appropriate value for TYPE,
11902 if (!TYPE_DEPENDENT_P_VALID (type))
11904 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11905 TYPE_DEPENDENT_P_VALID (type) = 1;
11908 return TYPE_DEPENDENT_P (type);
11911 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11914 dependent_scope_ref_p (tree expression, bool criterion (tree))
11919 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
11921 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11924 scope = TREE_OPERAND (expression, 0);
11925 name = TREE_OPERAND (expression, 1);
11929 An id-expression is type-dependent if it contains a
11930 nested-name-specifier that contains a class-name that names a
11932 /* The suggested resolution to Core Issue 2 implies that if the
11933 qualifying type is the current class, then we must peek
11936 && currently_open_class (scope)
11937 && !criterion (name))
11939 if (dependent_type_p (scope))
11945 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11946 [temp.dep.constexpr] */
11949 value_dependent_expression_p (tree expression)
11951 if (!processing_template_decl)
11954 /* A name declared with a dependent type. */
11955 if (TREE_CODE (expression) == IDENTIFIER_NODE
11956 || (DECL_P (expression)
11957 && type_dependent_expression_p (expression)))
11959 /* A non-type template parameter. */
11960 if ((TREE_CODE (expression) == CONST_DECL
11961 && DECL_TEMPLATE_PARM_P (expression))
11962 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11964 /* A constant with integral or enumeration type and is initialized
11965 with an expression that is value-dependent. */
11966 if (TREE_CODE (expression) == VAR_DECL
11967 && DECL_INITIAL (expression)
11968 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11969 && value_dependent_expression_p (DECL_INITIAL (expression)))
11971 /* These expressions are value-dependent if the type to which the
11972 cast occurs is dependent or the expression being casted is
11973 value-dependent. */
11974 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11975 || TREE_CODE (expression) == STATIC_CAST_EXPR
11976 || TREE_CODE (expression) == CONST_CAST_EXPR
11977 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11978 || TREE_CODE (expression) == CAST_EXPR)
11980 tree type = TREE_TYPE (expression);
11981 if (dependent_type_p (type))
11983 /* A functional cast has a list of operands. */
11984 expression = TREE_OPERAND (expression, 0);
11987 /* If there are no operands, it must be an expression such
11988 as "int()". This should not happen for aggregate types
11989 because it would form non-constant expressions. */
11990 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
11994 if (TREE_CODE (expression) == TREE_LIST)
11998 if (value_dependent_expression_p (TREE_VALUE (expression)))
12000 expression = TREE_CHAIN (expression);
12002 while (expression);
12006 return value_dependent_expression_p (expression);
12008 /* A `sizeof' expression is value-dependent if the operand is
12010 if (TREE_CODE (expression) == SIZEOF_EXPR
12011 || TREE_CODE (expression) == ALIGNOF_EXPR)
12013 expression = TREE_OPERAND (expression, 0);
12014 if (TYPE_P (expression))
12015 return dependent_type_p (expression);
12016 return type_dependent_expression_p (expression);
12018 if (TREE_CODE (expression) == SCOPE_REF)
12019 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12020 if (TREE_CODE (expression) == COMPONENT_REF)
12021 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12022 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12023 /* A constant expression is value-dependent if any subexpression is
12024 value-dependent. */
12025 if (EXPR_P (expression))
12027 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12030 return (value_dependent_expression_p
12031 (TREE_OPERAND (expression, 0)));
12032 case tcc_comparison:
12034 return ((value_dependent_expression_p
12035 (TREE_OPERAND (expression, 0)))
12036 || (value_dependent_expression_p
12037 (TREE_OPERAND (expression, 1))));
12038 case tcc_expression:
12041 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12042 /* In some cases, some of the operands may be missing.
12043 (For example, in the case of PREDECREMENT_EXPR, the
12044 amount to increment by may be missing.) That doesn't
12045 make the expression dependent. */
12046 if (TREE_OPERAND (expression, i)
12047 && (value_dependent_expression_p
12048 (TREE_OPERAND (expression, i))))
12052 case tcc_reference:
12053 case tcc_statement:
12054 /* These cannot be value dependent. */
12058 gcc_unreachable ();
12062 /* The expression is not value-dependent. */
12066 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12067 [temp.dep.expr]. */
12070 type_dependent_expression_p (tree expression)
12072 if (!processing_template_decl)
12075 if (expression == error_mark_node)
12078 /* An unresolved name is always dependent. */
12079 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12082 /* Some expression forms are never type-dependent. */
12083 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12084 || TREE_CODE (expression) == SIZEOF_EXPR
12085 || TREE_CODE (expression) == ALIGNOF_EXPR
12086 || TREE_CODE (expression) == TYPEID_EXPR
12087 || TREE_CODE (expression) == DELETE_EXPR
12088 || TREE_CODE (expression) == VEC_DELETE_EXPR
12089 || TREE_CODE (expression) == THROW_EXPR)
12092 /* The types of these expressions depends only on the type to which
12093 the cast occurs. */
12094 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12095 || TREE_CODE (expression) == STATIC_CAST_EXPR
12096 || TREE_CODE (expression) == CONST_CAST_EXPR
12097 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12098 || TREE_CODE (expression) == CAST_EXPR)
12099 return dependent_type_p (TREE_TYPE (expression));
12101 /* The types of these expressions depends only on the type created
12102 by the expression. */
12103 if (TREE_CODE (expression) == NEW_EXPR
12104 || TREE_CODE (expression) == VEC_NEW_EXPR)
12106 /* For NEW_EXPR tree nodes created inside a template, either
12107 the object type itself or a TREE_LIST may appear as the
12109 tree type = TREE_OPERAND (expression, 1);
12110 if (TREE_CODE (type) == TREE_LIST)
12111 /* This is an array type. We need to check array dimensions
12113 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12114 || value_dependent_expression_p
12115 (TREE_OPERAND (TREE_VALUE (type), 1));
12117 return dependent_type_p (type);
12120 if (TREE_CODE (expression) == SCOPE_REF
12121 && dependent_scope_ref_p (expression,
12122 type_dependent_expression_p))
12125 if (TREE_CODE (expression) == FUNCTION_DECL
12126 && DECL_LANG_SPECIFIC (expression)
12127 && DECL_TEMPLATE_INFO (expression)
12128 && (any_dependent_template_arguments_p
12129 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12132 if (TREE_CODE (expression) == TEMPLATE_DECL
12133 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12136 if (TREE_TYPE (expression) == unknown_type_node)
12138 if (TREE_CODE (expression) == ADDR_EXPR)
12139 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12140 if (TREE_CODE (expression) == COMPONENT_REF
12141 || TREE_CODE (expression) == OFFSET_REF)
12143 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12145 expression = TREE_OPERAND (expression, 1);
12146 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12149 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12150 if (TREE_CODE (expression) == SCOPE_REF)
12153 if (TREE_CODE (expression) == BASELINK)
12154 expression = BASELINK_FUNCTIONS (expression);
12156 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12158 if (any_dependent_template_arguments_p
12159 (TREE_OPERAND (expression, 1)))
12161 expression = TREE_OPERAND (expression, 0);
12163 gcc_assert (TREE_CODE (expression) == OVERLOAD);
12167 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12169 expression = OVL_NEXT (expression);
12174 return (dependent_type_p (TREE_TYPE (expression)));
12177 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12178 contains a type-dependent expression. */
12181 any_type_dependent_arguments_p (tree args)
12185 tree arg = TREE_VALUE (args);
12187 if (type_dependent_expression_p (arg))
12189 args = TREE_CHAIN (args);
12194 /* Returns TRUE if the ARG (a template argument) is dependent. */
12197 dependent_template_arg_p (tree arg)
12199 if (!processing_template_decl)
12202 if (TREE_CODE (arg) == TEMPLATE_DECL
12203 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12204 return dependent_template_p (arg);
12205 else if (TYPE_P (arg))
12206 return dependent_type_p (arg);
12208 return (type_dependent_expression_p (arg)
12209 || value_dependent_expression_p (arg));
12212 /* Returns true if ARGS (a collection of template arguments) contains
12213 any dependent arguments. */
12216 any_dependent_template_arguments_p (tree args)
12224 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12226 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12227 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12228 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12235 /* Returns TRUE if the template TMPL is dependent. */
12238 dependent_template_p (tree tmpl)
12240 if (TREE_CODE (tmpl) == OVERLOAD)
12244 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12246 tmpl = OVL_CHAIN (tmpl);
12251 /* Template template parameters are dependent. */
12252 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12253 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12255 /* So are names that have not been looked up. */
12256 if (TREE_CODE (tmpl) == SCOPE_REF
12257 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12259 /* So are member templates of dependent classes. */
12260 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12261 return dependent_type_p (DECL_CONTEXT (tmpl));
12265 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12268 dependent_template_id_p (tree tmpl, tree args)
12270 return (dependent_template_p (tmpl)
12271 || any_dependent_template_arguments_p (args));
12274 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12275 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12276 can be found. Note that this function peers inside uninstantiated
12277 templates and therefore should be used only in extremely limited
12281 resolve_typename_type (tree type, bool only_current_p)
12289 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12291 scope = TYPE_CONTEXT (type);
12292 name = TYPE_IDENTIFIER (type);
12294 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12295 it first before we can figure out what NAME refers to. */
12296 if (TREE_CODE (scope) == TYPENAME_TYPE)
12297 scope = resolve_typename_type (scope, only_current_p);
12298 /* If we don't know what SCOPE refers to, then we cannot resolve the
12300 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12301 return error_mark_node;
12302 /* If the SCOPE is a template type parameter, we have no way of
12303 resolving the name. */
12304 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12306 /* If the SCOPE is not the current instantiation, there's no reason
12307 to look inside it. */
12308 if (only_current_p && !currently_open_class (scope))
12309 return error_mark_node;
12310 /* If SCOPE is a partial instantiation, it will not have a valid
12311 TYPE_FIELDS list, so use the original template. */
12312 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12313 /* Enter the SCOPE so that name lookup will be resolved as if we
12314 were in the class definition. In particular, SCOPE will no
12315 longer be considered a dependent type. */
12316 pop_p = push_scope (scope);
12317 /* Look up the declaration. */
12318 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12319 /* Obtain the set of qualifiers applied to the TYPE. */
12320 quals = cp_type_quals (type);
12321 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12322 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12324 type = error_mark_node;
12325 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12326 && TREE_CODE (decl) == TYPE_DECL)
12327 type = TREE_TYPE (decl);
12328 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12329 && DECL_CLASS_TEMPLATE_P (decl))
12333 /* Obtain the template and the arguments. */
12334 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12335 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12336 /* Instantiate the template. */
12337 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12338 /*entering_scope=*/0, tf_error | tf_user);
12341 type = error_mark_node;
12342 /* Qualify the resulting type. */
12343 if (type != error_mark_node && quals)
12344 type = cp_build_qualified_type (type, quals);
12345 /* Leave the SCOPE. */
12352 /* EXPR is an expression which is not type-dependent. Return a proxy
12353 for EXPR that can be used to compute the types of larger
12354 expressions containing EXPR. */
12357 build_non_dependent_expr (tree expr)
12361 /* Preserve null pointer constants so that the type of things like
12362 "p == 0" where "p" is a pointer can be determined. */
12363 if (null_ptr_cst_p (expr))
12365 /* Preserve OVERLOADs; the functions must be available to resolve
12367 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12368 TREE_OPERAND (expr, 0) : expr);
12369 if (TREE_CODE (inner_expr) == OVERLOAD
12370 || TREE_CODE (inner_expr) == FUNCTION_DECL
12371 || TREE_CODE (inner_expr) == TEMPLATE_DECL
12372 || TREE_CODE (inner_expr) == TEMPLATE_ID_EXPR)
12374 /* There is no need to return a proxy for a variable. */
12375 if (TREE_CODE (expr) == VAR_DECL)
12377 /* Preserve string constants; conversions from string constants to
12378 "char *" are allowed, even though normally a "const char *"
12379 cannot be used to initialize a "char *". */
12380 if (TREE_CODE (expr) == STRING_CST)
12382 /* Preserve arithmetic constants, as an optimization -- there is no
12383 reason to create a new node. */
12384 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12386 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12387 There is at least one place where we want to know that a
12388 particular expression is a throw-expression: when checking a ?:
12389 expression, there are special rules if the second or third
12390 argument is a throw-expression. */
12391 if (TREE_CODE (expr) == THROW_EXPR)
12394 if (TREE_CODE (expr) == COND_EXPR)
12395 return build3 (COND_EXPR,
12397 TREE_OPERAND (expr, 0),
12398 (TREE_OPERAND (expr, 1)
12399 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12400 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12401 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12402 if (TREE_CODE (expr) == COMPOUND_EXPR
12403 && !COMPOUND_EXPR_OVERLOADED (expr))
12404 return build2 (COMPOUND_EXPR,
12406 TREE_OPERAND (expr, 0),
12407 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12409 /* Otherwise, build a NON_DEPENDENT_EXPR.
12411 REFERENCE_TYPEs are not stripped for expressions in templates
12412 because doing so would play havoc with mangling. Consider, for
12415 template <typename T> void f<T& g>() { g(); }
12417 In the body of "f", the expression for "g" will have
12418 REFERENCE_TYPE, even though the standard says that it should
12419 not. The reason is that we must preserve the syntactic form of
12420 the expression so that mangling (say) "f<g>" inside the body of
12421 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12423 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12426 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12427 Return a new TREE_LIST with the various arguments replaced with
12428 equivalent non-dependent expressions. */
12431 build_non_dependent_args (tree args)
12436 new_args = NULL_TREE;
12437 for (a = args; a; a = TREE_CHAIN (a))
12438 new_args = tree_cons (NULL_TREE,
12439 build_non_dependent_expr (TREE_VALUE (a)),
12441 return nreverse (new_args);
12444 #include "gt-cp-pt.h"