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 (tree, tree);
114 static tree convert_template_argument (tree, tree, tree,
115 tsubst_flags_t, int, tree);
116 static tree get_bindings_overload (tree, tree, tree);
117 static int for_each_template_parm (tree, tree_fn_t, void*,
118 struct pointer_set_t*);
119 static tree build_template_parm_index (int, int, int, tree, tree);
120 static int inline_needs_template_parms (tree);
121 static void push_inline_template_parms_recursive (tree, int);
122 static tree retrieve_local_specialization (tree);
123 static void register_local_specialization (tree, tree);
124 static tree reduce_template_parm_level (tree, tree, int);
125 static int mark_template_parm (tree, void *);
126 static int template_parm_this_level_p (tree, void *);
127 static tree tsubst_friend_function (tree, tree);
128 static tree tsubst_friend_class (tree, tree);
129 static int can_complete_type_without_circularity (tree);
130 static tree get_bindings (tree, tree, tree);
131 static tree get_bindings_real (tree, tree, tree, int, int, int);
132 static int template_decl_level (tree);
133 static int check_cv_quals_for_unify (int, tree, tree);
134 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
135 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
136 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
137 static void regenerate_decl_from_template (tree, tree);
138 static tree most_specialized (tree, tree, tree);
139 static tree most_specialized_class (tree, tree);
140 static int template_class_depth_real (tree, int);
141 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
142 static tree tsubst_decl (tree, tree, tree, tsubst_flags_t);
143 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
144 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
145 static void check_specialization_scope (void);
146 static tree process_partial_specialization (tree);
147 static void set_current_access_from_decl (tree);
148 static void check_default_tmpl_args (tree, tree, int, int);
149 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
150 static tree get_template_base (tree, tree, tree, tree);
151 static int verify_class_unification (tree, tree, tree);
152 static tree try_class_unification (tree, tree, tree, tree);
153 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
155 static tree determine_specialization (tree, tree, tree *, int, int);
156 static int template_args_equal (tree, tree);
157 static void tsubst_default_arguments (tree);
158 static tree for_each_template_parm_r (tree *, int *, void *);
159 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
160 static void copy_default_args_to_explicit_spec (tree);
161 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
162 static int eq_local_specializations (const void *, const void *);
163 static bool dependent_type_p_r (tree);
164 static tree tsubst (tree, tree, tsubst_flags_t, tree);
165 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
166 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
168 /* Make the current scope suitable for access checking when we are
169 processing T. T can be FUNCTION_DECL for instantiated function
170 template, or VAR_DECL for static member variable (need by
171 instantiate_decl). */
174 push_access_scope (tree t)
176 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
177 || TREE_CODE (t) == VAR_DECL);
179 if (DECL_CLASS_SCOPE_P (t))
180 push_nested_class (DECL_CONTEXT (t));
182 push_to_top_level ();
184 if (TREE_CODE (t) == FUNCTION_DECL)
186 saved_access_scope = tree_cons
187 (NULL_TREE, current_function_decl, saved_access_scope);
188 current_function_decl = t;
192 /* Restore the scope set up by push_access_scope. T is the node we
196 pop_access_scope (tree t)
198 if (TREE_CODE (t) == FUNCTION_DECL)
200 current_function_decl = TREE_VALUE (saved_access_scope);
201 saved_access_scope = TREE_CHAIN (saved_access_scope);
204 if (DECL_CLASS_SCOPE_P (t))
207 pop_from_top_level ();
210 /* Do any processing required when DECL (a member template
211 declaration) is finished. Returns the TEMPLATE_DECL corresponding
212 to DECL, unless it is a specialization, in which case the DECL
213 itself is returned. */
216 finish_member_template_decl (tree decl)
218 if (decl == error_mark_node)
219 return error_mark_node;
221 gcc_assert (DECL_P (decl));
223 if (TREE_CODE (decl) == TYPE_DECL)
227 type = TREE_TYPE (decl);
228 if (IS_AGGR_TYPE (type)
229 && CLASSTYPE_TEMPLATE_INFO (type)
230 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
232 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
233 check_member_template (tmpl);
238 else if (TREE_CODE (decl) == FIELD_DECL)
239 error ("data member %qD cannot be a member template", decl);
240 else if (DECL_TEMPLATE_INFO (decl))
242 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
244 check_member_template (DECL_TI_TEMPLATE (decl));
245 return DECL_TI_TEMPLATE (decl);
251 error ("invalid member template declaration %qD", decl);
253 return error_mark_node;
256 /* Returns the template nesting level of the indicated class TYPE.
266 A<T>::B<U> has depth two, while A<T> has depth one.
267 Both A<T>::B<int> and A<int>::B<U> have depth one, if
268 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
271 This function is guaranteed to return 0 if passed NULL_TREE so
272 that, for example, `template_class_depth (current_class_type)' is
276 template_class_depth_real (tree type, int count_specializations)
281 type && TREE_CODE (type) != NAMESPACE_DECL;
282 type = (TREE_CODE (type) == FUNCTION_DECL)
283 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
285 if (TREE_CODE (type) != FUNCTION_DECL)
287 if (CLASSTYPE_TEMPLATE_INFO (type)
288 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
289 && ((count_specializations
290 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
291 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
296 if (DECL_TEMPLATE_INFO (type)
297 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
298 && ((count_specializations
299 && DECL_TEMPLATE_SPECIALIZATION (type))
300 || uses_template_parms (DECL_TI_ARGS (type))))
308 /* Returns the template nesting level of the indicated class TYPE.
309 Like template_class_depth_real, but instantiations do not count in
313 template_class_depth (tree type)
315 return template_class_depth_real (type, /*count_specializations=*/0);
318 /* Returns 1 if processing DECL as part of do_pending_inlines
319 needs us to push template parms. */
322 inline_needs_template_parms (tree decl)
324 if (! DECL_TEMPLATE_INFO (decl))
327 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
328 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
331 /* Subroutine of maybe_begin_member_template_processing.
332 Push the template parms in PARMS, starting from LEVELS steps into the
333 chain, and ending at the beginning, since template parms are listed
337 push_inline_template_parms_recursive (tree parmlist, int levels)
339 tree parms = TREE_VALUE (parmlist);
343 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
345 ++processing_template_decl;
346 current_template_parms
347 = tree_cons (size_int (processing_template_decl),
348 parms, current_template_parms);
349 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
351 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
353 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
355 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
356 gcc_assert (DECL_P (parm));
358 switch (TREE_CODE (parm))
367 /* Make a CONST_DECL as is done in process_template_parm.
368 It is ugly that we recreate this here; the original
369 version built in process_template_parm is no longer
371 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
373 DECL_ARTIFICIAL (decl) = 1;
374 TREE_CONSTANT (decl) = 1;
375 TREE_INVARIANT (decl) = 1;
376 TREE_READONLY (decl) = 1;
377 DECL_INITIAL (decl) = DECL_INITIAL (parm);
378 SET_DECL_TEMPLATE_PARM_P (decl);
389 /* Restore the template parameter context for a member template or
390 a friend template defined in a class definition. */
393 maybe_begin_member_template_processing (tree decl)
398 if (inline_needs_template_parms (decl))
400 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
401 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
403 if (DECL_TEMPLATE_SPECIALIZATION (decl))
406 parms = TREE_CHAIN (parms);
409 push_inline_template_parms_recursive (parms, levels);
412 /* Remember how many levels of template parameters we pushed so that
413 we can pop them later. */
414 if (!inline_parm_levels)
415 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
416 if (inline_parm_levels_used == inline_parm_levels->num_elements)
417 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
418 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
419 ++inline_parm_levels_used;
422 /* Undo the effects of begin_member_template_processing. */
425 maybe_end_member_template_processing (void)
429 if (!inline_parm_levels_used)
432 --inline_parm_levels_used;
434 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
437 --processing_template_decl;
438 current_template_parms = TREE_CHAIN (current_template_parms);
443 /* Return a new template argument vector which contains all of ARGS,
444 but has as its innermost set of arguments the EXTRA_ARGS. */
447 add_to_template_args (tree args, tree extra_args)
454 extra_depth = TMPL_ARGS_DEPTH (extra_args);
455 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
457 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
458 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
460 for (j = 1; j <= extra_depth; ++j, ++i)
461 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
466 /* Like add_to_template_args, but only the outermost ARGS are added to
467 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
468 (EXTRA_ARGS) levels are added. This function is used to combine
469 the template arguments from a partial instantiation with the
470 template arguments used to attain the full instantiation from the
471 partial instantiation. */
474 add_outermost_template_args (tree args, tree extra_args)
478 /* If there are more levels of EXTRA_ARGS than there are ARGS,
479 something very fishy is going on. */
480 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
482 /* If *all* the new arguments will be the EXTRA_ARGS, just return
484 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
487 /* For the moment, we make ARGS look like it contains fewer levels. */
488 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
490 new_args = add_to_template_args (args, extra_args);
492 /* Now, we restore ARGS to its full dimensions. */
493 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
498 /* Return the N levels of innermost template arguments from the ARGS. */
501 get_innermost_template_args (tree args, int n)
509 /* If N is 1, just return the innermost set of template arguments. */
511 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
513 /* If we're not removing anything, just return the arguments we were
515 extra_levels = TMPL_ARGS_DEPTH (args) - n;
516 gcc_assert (extra_levels >= 0);
517 if (extra_levels == 0)
520 /* Make a new set of arguments, not containing the outer arguments. */
521 new_args = make_tree_vec (n);
522 for (i = 1; i <= n; ++i)
523 SET_TMPL_ARGS_LEVEL (new_args, i,
524 TMPL_ARGS_LEVEL (args, i + extra_levels));
529 /* We've got a template header coming up; push to a new level for storing
533 begin_template_parm_list (void)
535 /* We use a non-tag-transparent scope here, which causes pushtag to
536 put tags in this scope, rather than in the enclosing class or
537 namespace scope. This is the right thing, since we want
538 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
539 global template class, push_template_decl handles putting the
540 TEMPLATE_DECL into top-level scope. For a nested template class,
543 template <class T> struct S1 {
544 template <class T> struct S2 {};
547 pushtag contains special code to call pushdecl_with_scope on the
548 TEMPLATE_DECL for S2. */
549 begin_scope (sk_template_parms, NULL);
550 ++processing_template_decl;
551 ++processing_template_parmlist;
552 note_template_header (0);
555 /* This routine is called when a specialization is declared. If it is
556 invalid to declare a specialization here, an error is reported. */
559 check_specialization_scope (void)
561 tree scope = current_scope ();
565 An explicit specialization shall be declared in the namespace of
566 which the template is a member, or, for member templates, in the
567 namespace of which the enclosing class or enclosing class
568 template is a member. An explicit specialization of a member
569 function, member class or static data member of a class template
570 shall be declared in the namespace of which the class template
572 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
573 error ("explicit specialization in non-namespace scope %qD", scope);
577 In an explicit specialization declaration for a member of a class
578 template or a member template that appears in namespace scope,
579 the member template and some of its enclosing class templates may
580 remain unspecialized, except that the declaration shall not
581 explicitly specialize a class member template if its enclosing
582 class templates are not explicitly specialized as well. */
583 if (current_template_parms)
584 error ("enclosing class templates are not explicitly specialized");
587 /* We've just seen template <>. */
590 begin_specialization (void)
592 begin_scope (sk_template_spec, NULL);
593 note_template_header (1);
594 check_specialization_scope ();
597 /* Called at then end of processing a declaration preceded by
601 end_specialization (void)
604 reset_specialization ();
607 /* Any template <>'s that we have seen thus far are not referring to a
608 function specialization. */
611 reset_specialization (void)
613 processing_specialization = 0;
614 template_header_count = 0;
617 /* We've just seen a template header. If SPECIALIZATION is nonzero,
618 it was of the form template <>. */
621 note_template_header (int specialization)
623 processing_specialization = specialization;
624 template_header_count++;
627 /* We're beginning an explicit instantiation. */
630 begin_explicit_instantiation (void)
632 gcc_assert (!processing_explicit_instantiation);
633 processing_explicit_instantiation = true;
638 end_explicit_instantiation (void)
640 gcc_assert (processing_explicit_instantiation);
641 processing_explicit_instantiation = false;
644 /* A explicit specialization or partial specialization TMPL is being
645 declared. Check that the namespace in which the specialization is
646 occurring is permissible. Returns false iff it is invalid to
647 specialize TMPL in the current namespace. */
650 check_specialization_namespace (tree tmpl)
652 tree tpl_ns = decl_namespace_context (tmpl);
656 An explicit specialization shall be declared in the namespace of
657 which the template is a member, or, for member templates, in the
658 namespace of which the enclosing class or enclosing class
659 template is a member. An explicit specialization of a member
660 function, member class or static data member of a class template
661 shall be declared in the namespace of which the class template is
663 if (is_associated_namespace (current_namespace, tpl_ns))
664 /* Same or super-using namespace. */
668 pedwarn ("specialization of %qD in different namespace", tmpl);
669 cp_pedwarn_at (" from definition of %q#D", tmpl);
674 /* The TYPE is being declared. If it is a template type, that means it
675 is a partial specialization. Do appropriate error-checking. */
678 maybe_process_partial_specialization (tree type)
680 /* TYPE maybe an ERROR_MARK_NODE. */
681 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
683 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
685 /* This is for ordinary explicit specialization and partial
686 specialization of a template class such as:
688 template <> class C<int>;
692 template <class T> class C<T*>;
694 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
696 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
697 && !COMPLETE_TYPE_P (type))
699 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
700 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
701 if (processing_template_decl)
702 push_template_decl (TYPE_MAIN_DECL (type));
704 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
705 error ("specialization of %qT after instantiation", type);
707 else if (CLASS_TYPE_P (type)
708 && !CLASSTYPE_USE_TEMPLATE (type)
709 && CLASSTYPE_TEMPLATE_INFO (type)
710 && context && CLASS_TYPE_P (context)
711 && CLASSTYPE_TEMPLATE_INFO (context))
713 /* This is for an explicit specialization of member class
714 template according to [temp.expl.spec/18]:
716 template <> template <class U> class C<int>::D;
718 The context `C<int>' must be an implicit instantiation.
719 Otherwise this is just a member class template declared
722 template <> class C<int> { template <class U> class D; };
723 template <> template <class U> class C<int>::D;
725 In the first case, `C<int>::D' is a specialization of `C<T>::D'
726 while in the second case, `C<int>::D' is a primary template
727 and `C<T>::D' may not exist. */
729 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
730 && !COMPLETE_TYPE_P (type))
734 if (current_namespace
735 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
737 pedwarn ("specializing %q#T in different namespace", type);
738 cp_pedwarn_at (" from definition of %q#D",
739 CLASSTYPE_TI_TEMPLATE (type));
742 /* Check for invalid specialization after instantiation:
744 template <> template <> class C<int>::D<int>;
745 template <> template <class U> class C<int>::D; */
747 for (t = DECL_TEMPLATE_INSTANTIATIONS
748 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
749 t; t = TREE_CHAIN (t))
750 if (TREE_VALUE (t) != type
751 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
752 error ("specialization %qT after instantiation %qT",
753 type, TREE_VALUE (t));
755 /* Mark TYPE as a specialization. And as a result, we only
756 have one level of template argument for the innermost
758 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
759 CLASSTYPE_TI_ARGS (type)
760 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
763 else if (processing_specialization)
764 error ("explicit specialization of non-template %qT", type);
767 /* Returns nonzero if we can optimize the retrieval of specializations
768 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
769 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
772 optimize_specialization_lookup_p (tree tmpl)
774 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
775 && DECL_CLASS_SCOPE_P (tmpl)
776 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
778 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
779 /* The optimized lookup depends on the fact that the
780 template arguments for the member function template apply
781 purely to the containing class, which is not true if the
782 containing class is an explicit or partial
784 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
785 && !DECL_MEMBER_TEMPLATE_P (tmpl)
786 && !DECL_CONV_FN_P (tmpl)
787 /* It is possible to have a template that is not a member
788 template and is not a member of a template class:
790 template <typename T>
791 struct S { friend A::f(); };
793 Here, the friend function is a template, but the context does
794 not have template information. The optimized lookup relies
795 on having ARGS be the template arguments for both the class
796 and the function template. */
797 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
800 /* Retrieve the specialization (in the sense of [temp.spec] - a
801 specialization is either an instantiation or an explicit
802 specialization) of TMPL for the given template ARGS. If there is
803 no such specialization, return NULL_TREE. The ARGS are a vector of
804 arguments, or a vector of vectors of arguments, in the case of
805 templates with more than one level of parameters.
807 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
808 then we search for a partial specialization matching ARGS. This
809 parameter is ignored if TMPL is not a class template. */
812 retrieve_specialization (tree tmpl, tree args,
813 bool class_specializations_p)
815 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
817 /* There should be as many levels of arguments as there are
818 levels of parameters. */
819 gcc_assert (TMPL_ARGS_DEPTH (args)
820 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
822 if (optimize_specialization_lookup_p (tmpl))
825 tree class_specialization;
830 /* The template arguments actually apply to the containing
831 class. Find the class specialization with those
833 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
835 = retrieve_specialization (class_template, args,
836 /*class_specializations_p=*/false);
837 if (!class_specialization)
839 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
840 for the specialization. */
841 idx = class_method_index_for_fn (class_specialization, tmpl);
844 /* Iterate through the methods with the indicated name, looking
845 for the one that has an instance of TMPL. */
846 methods = CLASSTYPE_METHOD_VEC (class_specialization);
847 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
849 tree fn = OVL_CURRENT (fns);
850 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
860 /* Class templates store their instantiations on the
861 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
862 DECL_TEMPLATE_SPECIALIZATIONS list. */
863 if (!class_specializations_p
864 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
865 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
867 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
869 /* Iterate through the list until we find a matching template. */
870 while (*sp != NULL_TREE)
874 if (comp_template_args (TREE_PURPOSE (spec), args))
876 /* Use the move-to-front heuristic to speed up future
880 *sp = TREE_CHAIN (*sp);
881 TREE_CHAIN (spec) = *head;
884 return TREE_VALUE (spec);
886 sp = &TREE_CHAIN (spec);
893 /* Like retrieve_specialization, but for local declarations. */
896 retrieve_local_specialization (tree tmpl)
898 tree spec = htab_find_with_hash (local_specializations, tmpl,
899 htab_hash_pointer (tmpl));
900 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
903 /* Returns nonzero iff DECL is a specialization of TMPL. */
906 is_specialization_of (tree decl, tree tmpl)
910 if (TREE_CODE (decl) == FUNCTION_DECL)
914 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
920 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
922 for (t = TREE_TYPE (decl);
924 t = CLASSTYPE_USE_TEMPLATE (t)
925 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
926 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
933 /* Returns nonzero iff DECL is a specialization of friend declaration
934 FRIEND according to [temp.friend]. */
937 is_specialization_of_friend (tree decl, tree friend)
939 bool need_template = true;
942 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
943 || TREE_CODE (decl) == TYPE_DECL);
945 /* For [temp.friend/6] when FRIEND is an ordinary member function
946 of a template class, we want to check if DECL is a specialization
948 if (TREE_CODE (friend) == FUNCTION_DECL
949 && DECL_TEMPLATE_INFO (friend)
950 && !DECL_USE_TEMPLATE (friend))
952 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
953 friend = DECL_TI_TEMPLATE (friend);
954 need_template = false;
956 else if (TREE_CODE (friend) == TEMPLATE_DECL
957 && !PRIMARY_TEMPLATE_P (friend))
958 need_template = false;
960 /* There is nothing to do if this is not a template friend. */
961 if (TREE_CODE (friend) != TEMPLATE_DECL)
964 if (is_specialization_of (decl, friend))
968 A member of a class template may be declared to be a friend of a
969 non-template class. In this case, the corresponding member of
970 every specialization of the class template is a friend of the
971 class granting friendship.
973 For example, given a template friend declaration
975 template <class T> friend void A<T>::f();
977 the member function below is considered a friend
979 template <> struct A<int> {
983 For this type of template friend, TEMPLATE_DEPTH below will be
984 nonzero. To determine if DECL is a friend of FRIEND, we first
985 check if the enclosing class is a specialization of another. */
987 template_depth = template_class_depth (DECL_CONTEXT (friend));
989 && DECL_CLASS_SCOPE_P (decl)
990 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
991 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
993 /* Next, we check the members themselves. In order to handle
994 a few tricky cases, such as when FRIEND's are
996 template <class T> friend void A<T>::g(T t);
997 template <class T> template <T t> friend void A<T>::h();
1001 void A<int>::g(int);
1002 template <int> void A<int>::h();
1004 we need to figure out ARGS, the template arguments from
1005 the context of DECL. This is required for template substitution
1006 of `T' in the function parameter of `g' and template parameter
1007 of `h' in the above examples. Here ARGS corresponds to `int'. */
1009 tree context = DECL_CONTEXT (decl);
1010 tree args = NULL_TREE;
1011 int current_depth = 0;
1013 while (current_depth < template_depth)
1015 if (CLASSTYPE_TEMPLATE_INFO (context))
1017 if (current_depth == 0)
1018 args = TYPE_TI_ARGS (context);
1020 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1023 context = TYPE_CONTEXT (context);
1026 if (TREE_CODE (decl) == FUNCTION_DECL)
1031 tree friend_args_type;
1032 tree decl_args_type;
1034 /* Make sure that both DECL and FRIEND are templates or
1036 is_template = DECL_TEMPLATE_INFO (decl)
1037 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1038 if (need_template ^ is_template)
1040 else if (is_template)
1042 /* If both are templates, check template parameter list. */
1044 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1046 if (!comp_template_parms
1047 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1051 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1054 decl_type = TREE_TYPE (decl);
1056 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1057 tf_none, NULL_TREE);
1058 if (friend_type == error_mark_node)
1061 /* Check if return types match. */
1062 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1065 /* Check if function parameter types match, ignoring the
1066 `this' parameter. */
1067 friend_args_type = TYPE_ARG_TYPES (friend_type);
1068 decl_args_type = TYPE_ARG_TYPES (decl_type);
1069 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1070 friend_args_type = TREE_CHAIN (friend_args_type);
1071 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1072 decl_args_type = TREE_CHAIN (decl_args_type);
1074 return compparms (decl_args_type, friend_args_type);
1078 /* DECL is a TYPE_DECL */
1080 tree decl_type = TREE_TYPE (decl);
1082 /* Make sure that both DECL and FRIEND are templates or
1085 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1086 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1088 if (need_template ^ is_template)
1090 else if (is_template)
1093 /* If both are templates, check the name of the two
1094 TEMPLATE_DECL's first because is_friend didn't. */
1095 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1096 != DECL_NAME (friend))
1099 /* Now check template parameter list. */
1101 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1103 return comp_template_parms
1104 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1108 return (DECL_NAME (decl)
1109 == DECL_NAME (friend));
1115 /* Register the specialization SPEC as a specialization of TMPL with
1116 the indicated ARGS. Returns SPEC, or an equivalent prior
1117 declaration, if available. */
1120 register_specialization (tree spec, tree tmpl, tree args)
1124 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1126 if (TREE_CODE (spec) == FUNCTION_DECL
1127 && uses_template_parms (DECL_TI_ARGS (spec)))
1128 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1129 register it; we want the corresponding TEMPLATE_DECL instead.
1130 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1131 the more obvious `uses_template_parms (spec)' to avoid problems
1132 with default function arguments. In particular, given
1133 something like this:
1135 template <class T> void f(T t1, T t = T())
1137 the default argument expression is not substituted for in an
1138 instantiation unless and until it is actually needed. */
1141 /* There should be as many levels of arguments as there are
1142 levels of parameters. */
1143 gcc_assert (TMPL_ARGS_DEPTH (args)
1144 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
1146 fn = retrieve_specialization (tmpl, args,
1147 /*class_specializations_p=*/false);
1148 /* We can sometimes try to re-register a specialization that we've
1149 already got. In particular, regenerate_decl_from_template calls
1150 duplicate_decls which will update the specialization list. But,
1151 we'll still get called again here anyhow. It's more convenient
1152 to simply allow this than to try to prevent it. */
1155 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1157 if (DECL_TEMPLATE_INSTANTIATION (fn))
1160 || DECL_EXPLICIT_INSTANTIATION (fn))
1162 error ("specialization of %qD after instantiation",
1168 /* This situation should occur only if the first
1169 specialization is an implicit instantiation, the
1170 second is an explicit specialization, and the
1171 implicit instantiation has not yet been used. That
1172 situation can occur if we have implicitly
1173 instantiated a member function and then specialized
1176 We can also wind up here if a friend declaration that
1177 looked like an instantiation turns out to be a
1180 template <class T> void foo(T);
1181 class S { friend void foo<>(int) };
1182 template <> void foo(int);
1184 We transform the existing DECL in place so that any
1185 pointers to it become pointers to the updated
1188 If there was a definition for the template, but not
1189 for the specialization, we want this to look as if
1190 there were no definition, and vice versa. */
1191 DECL_INITIAL (fn) = NULL_TREE;
1192 duplicate_decls (spec, fn);
1197 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1199 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
1200 /* Dup decl failed, but this is a new definition. Set the
1201 line number so any errors match this new
1203 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1209 /* A specialization must be declared in the same namespace as the
1210 template it is specializing. */
1211 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1212 && !check_specialization_namespace (tmpl))
1213 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1215 if (!optimize_specialization_lookup_p (tmpl))
1216 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1217 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1222 /* Unregister the specialization SPEC as a specialization of TMPL.
1223 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1224 if the SPEC was listed as a specialization of TMPL. */
1227 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1231 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1233 s = &TREE_CHAIN (*s))
1234 if (TREE_VALUE (*s) == spec)
1237 *s = TREE_CHAIN (*s);
1239 TREE_VALUE (*s) = new_spec;
1246 /* Compare an entry in the local specializations hash table P1 (which
1247 is really a pointer to a TREE_LIST) with P2 (which is really a
1251 eq_local_specializations (const void *p1, const void *p2)
1253 return TREE_VALUE ((tree) p1) == (tree) p2;
1256 /* Hash P1, an entry in the local specializations table. */
1259 hash_local_specialization (const void* p1)
1261 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1264 /* Like register_specialization, but for local declarations. We are
1265 registering SPEC, an instantiation of TMPL. */
1268 register_local_specialization (tree spec, tree tmpl)
1272 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1273 htab_hash_pointer (tmpl), INSERT);
1274 *slot = build_tree_list (spec, tmpl);
1277 /* Print the list of candidate FNS in an error message. */
1280 print_candidates (tree fns)
1284 const char *str = "candidates are:";
1286 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1290 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1291 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
1296 /* Returns the template (one of the functions given by TEMPLATE_ID)
1297 which can be specialized to match the indicated DECL with the
1298 explicit template args given in TEMPLATE_ID. The DECL may be
1299 NULL_TREE if none is available. In that case, the functions in
1300 TEMPLATE_ID are non-members.
1302 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1303 specialization of a member template.
1305 The TEMPLATE_COUNT is the number of references to qualifying
1306 template classes that appeared in the name of the function. See
1307 check_explicit_specialization for a more accurate description.
1309 The template args (those explicitly specified and those deduced)
1310 are output in a newly created vector *TARGS_OUT.
1312 If it is impossible to determine the result, an error message is
1313 issued. The error_mark_node is returned to indicate failure. */
1316 determine_specialization (tree template_id,
1319 int need_member_template,
1324 tree explicit_targs;
1325 tree candidates = NULL_TREE;
1326 tree templates = NULL_TREE;
1328 struct cp_binding_level *b;
1330 *targs_out = NULL_TREE;
1332 if (template_id == error_mark_node)
1333 return error_mark_node;
1335 fns = TREE_OPERAND (template_id, 0);
1336 explicit_targs = TREE_OPERAND (template_id, 1);
1338 if (fns == error_mark_node)
1339 return error_mark_node;
1341 /* Check for baselinks. */
1342 if (BASELINK_P (fns))
1343 fns = BASELINK_FUNCTIONS (fns);
1345 if (!is_overloaded_fn (fns))
1347 error ("%qD is not a function template", fns);
1348 return error_mark_node;
1351 /* Count the number of template headers specified for this
1354 for (b = current_binding_level;
1355 b->kind == sk_template_parms || b->kind == sk_template_spec;
1359 for (; fns; fns = OVL_NEXT (fns))
1361 tree fn = OVL_CURRENT (fns);
1363 if (TREE_CODE (fn) == TEMPLATE_DECL)
1365 tree decl_arg_types;
1368 /* DECL might be a specialization of FN. */
1370 /* Adjust the type of DECL in case FN is a static member. */
1371 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1372 if (DECL_STATIC_FUNCTION_P (fn)
1373 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1374 decl_arg_types = TREE_CHAIN (decl_arg_types);
1376 /* Check that the number of function parameters matches.
1378 template <class T> void f(int i = 0);
1379 template <> void f<int>();
1380 The specialization f<int> is invalid but is not caught
1381 by get_bindings below. */
1383 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1384 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1387 /* For a non-static member function, we need to make sure that
1388 the const qualification is the same. This can be done by
1389 checking the 'this' in the argument list. */
1390 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1391 && !same_type_p (TREE_VALUE (fn_arg_types),
1392 TREE_VALUE (decl_arg_types)))
1395 /* In case of explicit specialization, we need to check if
1396 the number of template headers appearing in the specialization
1397 is correct. This is usually done in check_explicit_specialization,
1398 but the check done there cannot be exhaustive when specializing
1399 member functions. Consider the following code:
1401 template <> void A<int>::f(int);
1402 template <> template <> void A<int>::f(int);
1404 Assuming that A<int> is not itself an explicit specialization
1405 already, the first line specializes "f" which is a non-template
1406 member function, whilst the second line specializes "f" which
1407 is a template member function. So both lines are syntactically
1408 correct, and check_explicit_specialization does not reject
1411 Here, we can do better, as we are matching the specialization
1412 against the declarations. We count the number of template
1413 headers, and we check if they match TEMPLATE_COUNT + 1
1414 (TEMPLATE_COUNT is the number of qualifying template classes,
1415 plus there must be another header for the member template
1418 Notice that if header_count is zero, this is not a
1419 specialization but rather a template instantiation, so there
1420 is no check we can perform here. */
1421 if (header_count && header_count != template_count + 1)
1424 /* See whether this function might be a specialization of this
1426 targs = get_bindings (fn, decl, explicit_targs);
1429 /* We cannot deduce template arguments that when used to
1430 specialize TMPL will produce DECL. */
1433 /* Save this template, and the arguments deduced. */
1434 templates = tree_cons (targs, fn, templates);
1436 else if (need_member_template)
1437 /* FN is an ordinary member function, and we need a
1438 specialization of a member template. */
1440 else if (TREE_CODE (fn) != FUNCTION_DECL)
1441 /* We can get IDENTIFIER_NODEs here in certain erroneous
1444 else if (!DECL_FUNCTION_MEMBER_P (fn))
1445 /* This is just an ordinary non-member function. Nothing can
1446 be a specialization of that. */
1448 else if (DECL_ARTIFICIAL (fn))
1449 /* Cannot specialize functions that are created implicitly. */
1453 tree decl_arg_types;
1455 /* This is an ordinary member function. However, since
1456 we're here, we can assume it's enclosing class is a
1457 template class. For example,
1459 template <typename T> struct S { void f(); };
1460 template <> void S<int>::f() {}
1462 Here, S<int>::f is a non-template, but S<int> is a
1463 template class. If FN has the same type as DECL, we
1464 might be in business. */
1466 if (!DECL_TEMPLATE_INFO (fn))
1467 /* Its enclosing class is an explicit specialization
1468 of a template class. This is not a candidate. */
1471 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1472 TREE_TYPE (TREE_TYPE (fn))))
1473 /* The return types differ. */
1476 /* Adjust the type of DECL in case FN is a static member. */
1477 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1478 if (DECL_STATIC_FUNCTION_P (fn)
1479 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1480 decl_arg_types = TREE_CHAIN (decl_arg_types);
1482 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1485 candidates = tree_cons (NULL_TREE, fn, candidates);
1489 if (templates && TREE_CHAIN (templates))
1495 It is possible for a specialization with a given function
1496 signature to be instantiated from more than one function
1497 template. In such cases, explicit specification of the
1498 template arguments must be used to uniquely identify the
1499 function template specialization being specialized.
1501 Note that here, there's no suggestion that we're supposed to
1502 determine which of the candidate templates is most
1503 specialized. However, we, also have:
1507 Partial ordering of overloaded function template
1508 declarations is used in the following contexts to select
1509 the function template to which a function template
1510 specialization refers:
1512 -- when an explicit specialization refers to a function
1515 So, we do use the partial ordering rules, at least for now.
1516 This extension can only serve to make invalid programs valid,
1517 so it's safe. And, there is strong anecdotal evidence that
1518 the committee intended the partial ordering rules to apply;
1519 the EDG front-end has that behavior, and John Spicer claims
1520 that the committee simply forgot to delete the wording in
1521 [temp.expl.spec]. */
1522 tree tmpl = most_specialized (templates, decl, explicit_targs);
1523 if (tmpl && tmpl != error_mark_node)
1525 targs = get_bindings (tmpl, decl, explicit_targs);
1526 templates = tree_cons (targs, tmpl, NULL_TREE);
1530 if (templates == NULL_TREE && candidates == NULL_TREE)
1532 cp_error_at ("template-id %qD for %q+D does not match any template "
1535 return error_mark_node;
1537 else if ((templates && TREE_CHAIN (templates))
1538 || (candidates && TREE_CHAIN (candidates))
1539 || (templates && candidates))
1541 cp_error_at ("ambiguous template specialization %qD for %q+D",
1543 chainon (candidates, templates);
1544 print_candidates (candidates);
1545 return error_mark_node;
1548 /* We have one, and exactly one, match. */
1551 /* It was a specialization of an ordinary member function in a
1553 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1554 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1557 /* It was a specialization of a template. */
1558 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1559 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1561 *targs_out = copy_node (targs);
1562 SET_TMPL_ARGS_LEVEL (*targs_out,
1563 TMPL_ARGS_DEPTH (*targs_out),
1564 TREE_PURPOSE (templates));
1567 *targs_out = TREE_PURPOSE (templates);
1568 return TREE_VALUE (templates);
1571 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1572 but with the default argument values filled in from those in the
1576 copy_default_args_to_explicit_spec_1 (tree spec_types,
1579 tree new_spec_types;
1584 if (spec_types == void_list_node)
1585 return void_list_node;
1587 /* Substitute into the rest of the list. */
1589 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1590 TREE_CHAIN (tmpl_types));
1592 /* Add the default argument for this parameter. */
1593 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1594 TREE_VALUE (spec_types),
1598 /* DECL is an explicit specialization. Replicate default arguments
1599 from the template it specializes. (That way, code like:
1601 template <class T> void f(T = 3);
1602 template <> void f(double);
1605 works, as required.) An alternative approach would be to look up
1606 the correct default arguments at the call-site, but this approach
1607 is consistent with how implicit instantiations are handled. */
1610 copy_default_args_to_explicit_spec (tree decl)
1615 tree new_spec_types;
1619 tree object_type = NULL_TREE;
1620 tree in_charge = NULL_TREE;
1621 tree vtt = NULL_TREE;
1623 /* See if there's anything we need to do. */
1624 tmpl = DECL_TI_TEMPLATE (decl);
1625 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1626 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1627 if (TREE_PURPOSE (t))
1632 old_type = TREE_TYPE (decl);
1633 spec_types = TYPE_ARG_TYPES (old_type);
1635 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1637 /* Remove the this pointer, but remember the object's type for
1639 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1640 spec_types = TREE_CHAIN (spec_types);
1641 tmpl_types = TREE_CHAIN (tmpl_types);
1643 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1645 /* DECL may contain more parameters than TMPL due to the extra
1646 in-charge parameter in constructors and destructors. */
1647 in_charge = spec_types;
1648 spec_types = TREE_CHAIN (spec_types);
1650 if (DECL_HAS_VTT_PARM_P (decl))
1653 spec_types = TREE_CHAIN (spec_types);
1657 /* Compute the merged default arguments. */
1659 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1661 /* Compute the new FUNCTION_TYPE. */
1665 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1670 /* Put the in-charge parameter back. */
1671 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1672 TREE_VALUE (in_charge),
1675 new_type = build_method_type_directly (object_type,
1676 TREE_TYPE (old_type),
1680 new_type = build_function_type (TREE_TYPE (old_type),
1682 new_type = cp_build_type_attribute_variant (new_type,
1683 TYPE_ATTRIBUTES (old_type));
1684 new_type = build_exception_variant (new_type,
1685 TYPE_RAISES_EXCEPTIONS (old_type));
1686 TREE_TYPE (decl) = new_type;
1689 /* Check to see if the function just declared, as indicated in
1690 DECLARATOR, and in DECL, is a specialization of a function
1691 template. We may also discover that the declaration is an explicit
1692 instantiation at this point.
1694 Returns DECL, or an equivalent declaration that should be used
1695 instead if all goes well. Issues an error message if something is
1696 amiss. Returns error_mark_node if the error is not easily
1699 FLAGS is a bitmask consisting of the following flags:
1701 2: The function has a definition.
1702 4: The function is a friend.
1704 The TEMPLATE_COUNT is the number of references to qualifying
1705 template classes that appeared in the name of the function. For
1708 template <class T> struct S { void f(); };
1711 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1712 classes are not counted in the TEMPLATE_COUNT, so that in
1714 template <class T> struct S {};
1715 template <> struct S<int> { void f(); }
1716 template <> void S<int>::f();
1718 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1719 invalid; there should be no template <>.)
1721 If the function is a specialization, it is marked as such via
1722 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1723 is set up correctly, and it is added to the list of specializations
1724 for that template. */
1727 check_explicit_specialization (tree declarator,
1732 int have_def = flags & 2;
1733 int is_friend = flags & 4;
1734 int specialization = 0;
1735 int explicit_instantiation = 0;
1736 int member_specialization = 0;
1737 tree ctype = DECL_CLASS_CONTEXT (decl);
1738 tree dname = DECL_NAME (decl);
1741 tsk = current_tmpl_spec_kind (template_count);
1746 if (processing_specialization)
1749 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1751 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1754 /* This could be something like:
1756 template <class T> void f(T);
1757 class S { friend void f<>(int); } */
1761 /* This case handles bogus declarations like template <>
1762 template <class T> void f<int>(); */
1764 error ("template-id %qD in declaration of primary template",
1771 case tsk_invalid_member_spec:
1772 /* The error has already been reported in
1773 check_specialization_scope. */
1774 return error_mark_node;
1776 case tsk_invalid_expl_inst:
1777 error ("template parameter list used in explicit instantiation");
1783 error ("definition provided for explicit instantiation");
1785 explicit_instantiation = 1;
1788 case tsk_excessive_parms:
1789 case tsk_insufficient_parms:
1790 if (tsk == tsk_excessive_parms)
1791 error ("too many template parameter lists in declaration of %qD",
1793 else if (template_header_count)
1794 error("too few template parameter lists in declaration of %qD", decl);
1796 error("explicit specialization of %qD must be introduced by "
1797 "`template <>'", decl);
1801 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1803 member_specialization = 1;
1809 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1811 /* This case handles bogus declarations like template <>
1812 template <class T> void f<int>(); */
1814 if (uses_template_parms (declarator))
1815 error ("function template partial specialization %qD "
1816 "is not allowed", declarator);
1818 error ("template-id %qD in declaration of primary template",
1823 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1824 /* This is a specialization of a member template, without
1825 specialization the containing class. Something like:
1827 template <class T> struct S {
1828 template <class U> void f (U);
1830 template <> template <class U> void S<int>::f(U) {}
1832 That's a specialization -- but of the entire template. */
1840 if (specialization || member_specialization)
1842 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1843 for (; t; t = TREE_CHAIN (t))
1844 if (TREE_PURPOSE (t))
1847 ("default argument specified in explicit specialization");
1850 if (current_lang_name == lang_name_c)
1851 error ("template specialization with C linkage");
1854 if (specialization || member_specialization || explicit_instantiation)
1856 tree tmpl = NULL_TREE;
1857 tree targs = NULL_TREE;
1859 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1860 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1864 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1869 /* If there is no class context, the explicit instantiation
1870 must be at namespace scope. */
1871 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1873 /* Find the namespace binding, using the declaration
1875 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1878 declarator = lookup_template_function (fns, NULL_TREE);
1881 if (declarator == error_mark_node)
1882 return error_mark_node;
1884 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1886 if (!explicit_instantiation)
1887 /* A specialization in class scope. This is invalid,
1888 but the error will already have been flagged by
1889 check_specialization_scope. */
1890 return error_mark_node;
1893 /* It's not valid to write an explicit instantiation in
1896 class C { template void f(); }
1898 This case is caught by the parser. However, on
1901 template class C { void f(); };
1903 (which is invalid) we can get here. The error will be
1910 else if (ctype != NULL_TREE
1911 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1914 /* Find the list of functions in ctype that have the same
1915 name as the declared function. */
1916 tree name = TREE_OPERAND (declarator, 0);
1917 tree fns = NULL_TREE;
1920 if (constructor_name_p (name, ctype))
1922 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1924 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1925 : !TYPE_HAS_DESTRUCTOR (ctype))
1927 /* From [temp.expl.spec]:
1929 If such an explicit specialization for the member
1930 of a class template names an implicitly-declared
1931 special member function (clause _special_), the
1932 program is ill-formed.
1934 Similar language is found in [temp.explicit]. */
1935 error ("specialization of implicitly-declared special member function");
1936 return error_mark_node;
1939 name = is_constructor ? ctor_identifier : dtor_identifier;
1942 if (!DECL_CONV_FN_P (decl))
1944 idx = lookup_fnfields_1 (ctype, name);
1946 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1953 /* For a type-conversion operator, we cannot do a
1954 name-based lookup. We might be looking for `operator
1955 int' which will be a specialization of `operator T'.
1956 So, we find *all* the conversion operators, and then
1957 select from them. */
1960 methods = CLASSTYPE_METHOD_VEC (ctype);
1962 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1963 VEC_iterate (tree, methods, idx, ovl);
1966 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1967 /* There are no more conversion functions. */
1970 /* Glue all these conversion functions together
1971 with those we already have. */
1972 for (; ovl; ovl = OVL_NEXT (ovl))
1973 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1977 if (fns == NULL_TREE)
1979 error ("no member function %qD declared in %qT", name, ctype);
1980 return error_mark_node;
1983 TREE_OPERAND (declarator, 0) = fns;
1986 /* Figure out what exactly is being specialized at this point.
1987 Note that for an explicit instantiation, even one for a
1988 member function, we cannot tell apriori whether the
1989 instantiation is for a member template, or just a member
1990 function of a template class. Even if a member template is
1991 being instantiated, the member template arguments may be
1992 elided if they can be deduced from the rest of the
1994 tmpl = determine_specialization (declarator, decl,
1996 member_specialization,
1999 if (!tmpl || tmpl == error_mark_node)
2000 /* We couldn't figure out what this declaration was
2002 return error_mark_node;
2005 tree gen_tmpl = most_general_template (tmpl);
2007 if (explicit_instantiation)
2009 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2010 is done by do_decl_instantiation later. */
2012 int arg_depth = TMPL_ARGS_DEPTH (targs);
2013 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2015 if (arg_depth > parm_depth)
2017 /* If TMPL is not the most general template (for
2018 example, if TMPL is a friend template that is
2019 injected into namespace scope), then there will
2020 be too many levels of TARGS. Remove some of them
2025 new_targs = make_tree_vec (parm_depth);
2026 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2027 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2028 = TREE_VEC_ELT (targs, i);
2032 return instantiate_template (tmpl, targs, tf_error);
2035 /* If we thought that the DECL was a member function, but it
2036 turns out to be specializing a static member function,
2037 make DECL a static member function as well. */
2038 if (DECL_STATIC_FUNCTION_P (tmpl)
2039 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2040 revert_static_member_fn (decl);
2042 /* If this is a specialization of a member template of a
2043 template class. In we want to return the TEMPLATE_DECL,
2044 not the specialization of it. */
2045 if (tsk == tsk_template)
2047 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2048 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2051 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2052 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2053 = DECL_SOURCE_LOCATION (decl);
2058 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2059 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2061 /* Inherit default function arguments from the template
2062 DECL is specializing. */
2063 copy_default_args_to_explicit_spec (decl);
2065 /* This specialization has the same protection as the
2066 template it specializes. */
2067 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2068 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2070 if (is_friend && !have_def)
2071 /* This is not really a declaration of a specialization.
2072 It's just the name of an instantiation. But, it's not
2073 a request for an instantiation, either. */
2074 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2075 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2076 /* This is indeed a specialization. In case of constructors
2077 and destructors, we need in-charge and not-in-charge
2078 versions in V3 ABI. */
2079 clone_function_decl (decl, /*update_method_vec_p=*/0);
2081 /* Register this specialization so that we can find it
2083 decl = register_specialization (decl, gen_tmpl, targs);
2090 /* TYPE is being declared. Verify that the use of template headers
2091 and such is reasonable. Issue error messages if not. */
2094 maybe_check_template_type (tree type)
2096 if (template_header_count)
2098 /* We are in the scope of some `template <...>' header. */
2101 = template_class_depth_real (TYPE_CONTEXT (type),
2102 /*count_specializations=*/1);
2104 if (template_header_count <= context_depth)
2105 /* This is OK; the template headers are for the context. We
2106 are actually too lenient here; like
2107 check_explicit_specialization we should consider the number
2108 of template types included in the actual declaration. For
2111 template <class T> struct S {
2112 template <class U> template <class V>
2118 template <class T> struct S {
2119 template <class U> struct I;
2122 template <class T> template <class U.
2127 else if (template_header_count > context_depth + 1)
2128 /* There are two many template parameter lists. */
2129 error ("too many template parameter lists in declaration of %qT", type);
2133 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2134 parameters. These are represented in the same format used for
2135 DECL_TEMPLATE_PARMS. */
2138 comp_template_parms (tree parms1, tree parms2)
2143 if (parms1 == parms2)
2146 for (p1 = parms1, p2 = parms2;
2147 p1 != NULL_TREE && p2 != NULL_TREE;
2148 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2150 tree t1 = TREE_VALUE (p1);
2151 tree t2 = TREE_VALUE (p2);
2154 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2155 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2157 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2160 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2162 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2163 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2165 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2168 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2170 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2175 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2176 /* One set of parameters has more parameters lists than the
2183 /* Complain if DECL shadows a template parameter.
2185 [temp.local]: A template-parameter shall not be redeclared within its
2186 scope (including nested scopes). */
2189 check_template_shadow (tree decl)
2193 /* If we're not in a template, we can't possibly shadow a template
2195 if (!current_template_parms)
2198 /* Figure out what we're shadowing. */
2199 if (TREE_CODE (decl) == OVERLOAD)
2200 decl = OVL_CURRENT (decl);
2201 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2203 /* If there's no previous binding for this name, we're not shadowing
2204 anything, let alone a template parameter. */
2208 /* If we're not shadowing a template parameter, we're done. Note
2209 that OLDDECL might be an OVERLOAD (or perhaps even an
2210 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2212 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2215 /* We check for decl != olddecl to avoid bogus errors for using a
2216 name inside a class. We check TPFI to avoid duplicate errors for
2217 inline member templates. */
2219 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2222 cp_error_at ("declaration of %q#D", decl);
2223 cp_error_at (" shadows template parm %q#D", olddecl);
2226 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2227 ORIG_LEVEL, DECL, and TYPE. */
2230 build_template_parm_index (int index,
2236 tree t = make_node (TEMPLATE_PARM_INDEX);
2237 TEMPLATE_PARM_IDX (t) = index;
2238 TEMPLATE_PARM_LEVEL (t) = level;
2239 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2240 TEMPLATE_PARM_DECL (t) = decl;
2241 TREE_TYPE (t) = type;
2242 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2243 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2244 TREE_READONLY (t) = TREE_READONLY (decl);
2249 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2250 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2251 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2252 new one is created. */
2255 reduce_template_parm_level (tree index, tree type, int levels)
2257 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2258 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2259 != TEMPLATE_PARM_LEVEL (index) - levels))
2261 tree orig_decl = TEMPLATE_PARM_DECL (index);
2264 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2265 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2266 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2267 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2268 DECL_ARTIFICIAL (decl) = 1;
2269 SET_DECL_TEMPLATE_PARM_P (decl);
2271 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2272 TEMPLATE_PARM_LEVEL (index) - levels,
2273 TEMPLATE_PARM_ORIG_LEVEL (index),
2275 TEMPLATE_PARM_DESCENDANTS (index) = t;
2277 /* Template template parameters need this. */
2278 DECL_TEMPLATE_PARMS (decl)
2279 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2282 return TEMPLATE_PARM_DESCENDANTS (index);
2285 /* Process information from new template parameter NEXT and append it to the
2286 LIST being built. This new parameter is a non-type parameter iff
2287 IS_NON_TYPE is true. */
2290 process_template_parm (tree list, tree next, bool is_non_type)
2298 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2299 defval = TREE_PURPOSE (parm);
2303 tree p = TREE_VALUE (tree_last (list));
2305 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2306 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2308 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2316 parm = TREE_VALUE (parm);
2318 SET_DECL_TEMPLATE_PARM_P (parm);
2322 The top-level cv-qualifiers on the template-parameter are
2323 ignored when determining its type. */
2324 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2326 /* A template parameter is not modifiable. */
2327 TREE_CONSTANT (parm) = 1;
2328 TREE_INVARIANT (parm) = 1;
2329 TREE_READONLY (parm) = 1;
2330 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2331 TREE_TYPE (parm) = void_type_node;
2332 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2333 TREE_CONSTANT (decl) = 1;
2334 TREE_INVARIANT (decl) = 1;
2335 TREE_READONLY (decl) = 1;
2336 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2337 = build_template_parm_index (idx, processing_template_decl,
2338 processing_template_decl,
2339 decl, TREE_TYPE (parm));
2344 parm = TREE_VALUE (TREE_VALUE (parm));
2346 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2348 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2349 /* This is for distinguishing between real templates and template
2350 template parameters */
2351 TREE_TYPE (parm) = t;
2352 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2357 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2358 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2359 decl = build_decl (TYPE_DECL, parm, t);
2362 TYPE_NAME (t) = decl;
2363 TYPE_STUB_DECL (t) = decl;
2365 TEMPLATE_TYPE_PARM_INDEX (t)
2366 = build_template_parm_index (idx, processing_template_decl,
2367 processing_template_decl,
2368 decl, TREE_TYPE (parm));
2370 DECL_ARTIFICIAL (decl) = 1;
2371 SET_DECL_TEMPLATE_PARM_P (decl);
2373 parm = build_tree_list (defval, parm);
2374 return chainon (list, parm);
2377 /* The end of a template parameter list has been reached. Process the
2378 tree list into a parameter vector, converting each parameter into a more
2379 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2383 end_template_parm_list (tree parms)
2387 tree saved_parmlist = make_tree_vec (list_length (parms));
2389 current_template_parms
2390 = tree_cons (size_int (processing_template_decl),
2391 saved_parmlist, current_template_parms);
2393 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2395 next = TREE_CHAIN (parm);
2396 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2397 TREE_CHAIN (parm) = NULL_TREE;
2400 --processing_template_parmlist;
2402 return saved_parmlist;
2405 /* end_template_decl is called after a template declaration is seen. */
2408 end_template_decl (void)
2410 reset_specialization ();
2412 if (! processing_template_decl)
2415 /* This matches the pushlevel in begin_template_parm_list. */
2418 --processing_template_decl;
2419 current_template_parms = TREE_CHAIN (current_template_parms);
2422 /* Given a template argument vector containing the template PARMS.
2423 The innermost PARMS are given first. */
2426 current_template_args (void)
2429 tree args = NULL_TREE;
2430 int length = TMPL_PARMS_DEPTH (current_template_parms);
2433 /* If there is only one level of template parameters, we do not
2434 create a TREE_VEC of TREE_VECs. Instead, we return a single
2435 TREE_VEC containing the arguments. */
2437 args = make_tree_vec (length);
2439 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2441 tree a = copy_node (TREE_VALUE (header));
2444 TREE_TYPE (a) = NULL_TREE;
2445 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2447 tree t = TREE_VEC_ELT (a, i);
2449 /* T will be a list if we are called from within a
2450 begin/end_template_parm_list pair, but a vector directly
2451 if within a begin/end_member_template_processing pair. */
2452 if (TREE_CODE (t) == TREE_LIST)
2456 if (TREE_CODE (t) == TYPE_DECL
2457 || TREE_CODE (t) == TEMPLATE_DECL)
2460 t = DECL_INITIAL (t);
2461 TREE_VEC_ELT (a, i) = t;
2466 TREE_VEC_ELT (args, --l) = a;
2474 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2475 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2476 a member template. Used by push_template_decl below. */
2479 build_template_decl (tree decl, tree parms, bool member_template_p)
2481 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2482 DECL_TEMPLATE_PARMS (tmpl) = parms;
2483 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2484 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2485 if (DECL_LANG_SPECIFIC (decl))
2487 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2488 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2489 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2490 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2491 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2492 if (DECL_OVERLOADED_OPERATOR_P (decl))
2493 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2494 DECL_OVERLOADED_OPERATOR_P (decl));
2500 struct template_parm_data
2502 /* The level of the template parameters we are currently
2506 /* The index of the specialization argument we are currently
2510 /* An array whose size is the number of template parameters. The
2511 elements are nonzero if the parameter has been used in any one
2512 of the arguments processed so far. */
2515 /* An array whose size is the number of template arguments. The
2516 elements are nonzero if the argument makes use of template
2517 parameters of this level. */
2518 int* arg_uses_template_parms;
2521 /* Subroutine of push_template_decl used to see if each template
2522 parameter in a partial specialization is used in the explicit
2523 argument list. If T is of the LEVEL given in DATA (which is
2524 treated as a template_parm_data*), then DATA->PARMS is marked
2528 mark_template_parm (tree t, void* data)
2532 struct template_parm_data* tpd = (struct template_parm_data*) data;
2534 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2536 level = TEMPLATE_PARM_LEVEL (t);
2537 idx = TEMPLATE_PARM_IDX (t);
2541 level = TEMPLATE_TYPE_LEVEL (t);
2542 idx = TEMPLATE_TYPE_IDX (t);
2545 if (level == tpd->level)
2547 tpd->parms[idx] = 1;
2548 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2551 /* Return zero so that for_each_template_parm will continue the
2552 traversal of the tree; we want to mark *every* template parm. */
2556 /* Process the partial specialization DECL. */
2559 process_partial_specialization (tree decl)
2561 tree type = TREE_TYPE (decl);
2562 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2563 tree specargs = CLASSTYPE_TI_ARGS (type);
2564 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2565 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2566 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2567 int nargs = TREE_VEC_LENGTH (inner_args);
2568 int ntparms = TREE_VEC_LENGTH (inner_parms);
2570 int did_error_intro = 0;
2571 struct template_parm_data tpd;
2572 struct template_parm_data tpd2;
2574 /* We check that each of the template parameters given in the
2575 partial specialization is used in the argument list to the
2576 specialization. For example:
2578 template <class T> struct S;
2579 template <class T> struct S<T*>;
2581 The second declaration is OK because `T*' uses the template
2582 parameter T, whereas
2584 template <class T> struct S<int>;
2586 is no good. Even trickier is:
2597 The S2<T> declaration is actually invalid; it is a
2598 full-specialization. Of course,
2601 struct S2<T (*)(U)>;
2603 or some such would have been OK. */
2604 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2605 tpd.parms = alloca (sizeof (int) * ntparms);
2606 memset (tpd.parms, 0, sizeof (int) * ntparms);
2608 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2609 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2610 for (i = 0; i < nargs; ++i)
2612 tpd.current_arg = i;
2613 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2614 &mark_template_parm,
2618 for (i = 0; i < ntparms; ++i)
2619 if (tpd.parms[i] == 0)
2621 /* One of the template parms was not used in the
2623 if (!did_error_intro)
2625 error ("template parameters not used in partial specialization:");
2626 did_error_intro = 1;
2629 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2632 /* [temp.class.spec]
2634 The argument list of the specialization shall not be identical to
2635 the implicit argument list of the primary template. */
2636 if (comp_template_args
2638 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2640 error ("partial specialization %qT does not specialize any template arguments", type);
2642 /* [temp.class.spec]
2644 A partially specialized non-type argument expression shall not
2645 involve template parameters of the partial specialization except
2646 when the argument expression is a simple identifier.
2648 The type of a template parameter corresponding to a specialized
2649 non-type argument shall not be dependent on a parameter of the
2651 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2653 for (i = 0; i < nargs; ++i)
2655 tree arg = TREE_VEC_ELT (inner_args, i);
2656 if (/* These first two lines are the `non-type' bit. */
2658 && TREE_CODE (arg) != TEMPLATE_DECL
2659 /* This next line is the `argument expression is not just a
2660 simple identifier' condition and also the `specialized
2661 non-type argument' bit. */
2662 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2664 if (tpd.arg_uses_template_parms[i])
2665 error ("template argument %qE involves template parameter(s)", arg);
2668 /* Look at the corresponding template parameter,
2669 marking which template parameters its type depends
2672 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2677 /* We haven't yet initialized TPD2. Do so now. */
2678 tpd2.arg_uses_template_parms
2679 = alloca (sizeof (int) * nargs);
2680 /* The number of parameters here is the number in the
2681 main template, which, as checked in the assertion
2683 tpd2.parms = alloca (sizeof (int) * nargs);
2685 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2688 /* Mark the template parameters. But this time, we're
2689 looking for the template parameters of the main
2690 template, not in the specialization. */
2691 tpd2.current_arg = i;
2692 tpd2.arg_uses_template_parms[i] = 0;
2693 memset (tpd2.parms, 0, sizeof (int) * nargs);
2694 for_each_template_parm (type,
2695 &mark_template_parm,
2699 if (tpd2.arg_uses_template_parms [i])
2701 /* The type depended on some template parameters.
2702 If they are fully specialized in the
2703 specialization, that's OK. */
2705 for (j = 0; j < nargs; ++j)
2706 if (tpd2.parms[j] != 0
2707 && tpd.arg_uses_template_parms [j])
2709 error ("type %qT of template argument %qE depends "
2710 "on template parameter(s)",
2720 if (retrieve_specialization (maintmpl, specargs,
2721 /*class_specializations_p=*/true))
2722 /* We've already got this specialization. */
2725 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2726 = tree_cons (inner_args, inner_parms,
2727 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2728 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2732 /* Check that a template declaration's use of default arguments is not
2733 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2734 nonzero if DECL is the thing declared by a primary template.
2735 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2738 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2741 int last_level_to_check;
2746 A default template-argument shall not be specified in a
2747 function template declaration or a function template definition, nor
2748 in the template-parameter-list of the definition of a member of a
2751 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2752 /* You can't have a function template declaration in a local
2753 scope, nor you can you define a member of a class template in a
2757 if (current_class_type
2758 && !TYPE_BEING_DEFINED (current_class_type)
2759 && DECL_LANG_SPECIFIC (decl)
2760 /* If this is either a friend defined in the scope of the class
2761 or a member function. */
2762 && (DECL_FUNCTION_MEMBER_P (decl)
2763 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2764 : DECL_FRIEND_CONTEXT (decl)
2765 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2767 /* And, if it was a member function, it really was defined in
2768 the scope of the class. */
2769 && (!DECL_FUNCTION_MEMBER_P (decl)
2770 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2771 /* We already checked these parameters when the template was
2772 declared, so there's no need to do it again now. This function
2773 was defined in class scope, but we're processing it's body now
2774 that the class is complete. */
2779 If a template-parameter has a default template-argument, all
2780 subsequent template-parameters shall have a default
2781 template-argument supplied. */
2782 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2784 tree inner_parms = TREE_VALUE (parm_level);
2785 int ntparms = TREE_VEC_LENGTH (inner_parms);
2786 int seen_def_arg_p = 0;
2789 for (i = 0; i < ntparms; ++i)
2791 tree parm = TREE_VEC_ELT (inner_parms, i);
2792 if (TREE_PURPOSE (parm))
2794 else if (seen_def_arg_p)
2796 error ("no default argument for %qD", TREE_VALUE (parm));
2797 /* For better subsequent error-recovery, we indicate that
2798 there should have been a default argument. */
2799 TREE_PURPOSE (parm) = error_mark_node;
2804 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2805 /* For an ordinary class template, default template arguments are
2806 allowed at the innermost level, e.g.:
2807 template <class T = int>
2809 but, in a partial specialization, they're not allowed even
2810 there, as we have in [temp.class.spec]:
2812 The template parameter list of a specialization shall not
2813 contain default template argument values.
2815 So, for a partial specialization, or for a function template,
2816 we look at all of them. */
2819 /* But, for a primary class template that is not a partial
2820 specialization we look at all template parameters except the
2822 parms = TREE_CHAIN (parms);
2824 /* Figure out what error message to issue. */
2825 if (TREE_CODE (decl) == FUNCTION_DECL)
2826 msg = "default template arguments may not be used in function templates";
2827 else if (is_partial)
2828 msg = "default template arguments may not be used in partial specializations";
2830 msg = "default argument for template parameter for class enclosing %qD";
2832 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2833 /* If we're inside a class definition, there's no need to
2834 examine the parameters to the class itself. On the one
2835 hand, they will be checked when the class is defined, and,
2836 on the other, default arguments are valid in things like:
2837 template <class T = double>
2838 struct S { template <class U> void f(U); };
2839 Here the default argument for `S' has no bearing on the
2840 declaration of `f'. */
2841 last_level_to_check = template_class_depth (current_class_type) + 1;
2843 /* Check everything. */
2844 last_level_to_check = 0;
2846 for (parm_level = parms;
2847 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2848 parm_level = TREE_CHAIN (parm_level))
2850 tree inner_parms = TREE_VALUE (parm_level);
2854 ntparms = TREE_VEC_LENGTH (inner_parms);
2855 for (i = 0; i < ntparms; ++i)
2856 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2864 /* Clear out the default argument so that we are not
2866 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2869 /* At this point, if we're still interested in issuing messages,
2870 they must apply to classes surrounding the object declared. */
2872 msg = "default argument for template parameter for class enclosing %qD";
2876 /* Worker for push_template_decl_real, called via
2877 for_each_template_parm. DATA is really an int, indicating the
2878 level of the parameters we are interested in. If T is a template
2879 parameter of that level, return nonzero. */
2882 template_parm_this_level_p (tree t, void* data)
2884 int this_level = *(int *)data;
2887 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2888 level = TEMPLATE_PARM_LEVEL (t);
2890 level = TEMPLATE_TYPE_LEVEL (t);
2891 return level == this_level;
2894 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2895 parameters given by current_template_args, or reuses a
2896 previously existing one, if appropriate. Returns the DECL, or an
2897 equivalent one, if it is replaced via a call to duplicate_decls.
2899 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2902 push_template_decl_real (tree decl, int is_friend)
2910 int new_template_p = 0;
2911 /* True if the template is a member template, in the sense of
2913 bool member_template_p = false;
2915 if (decl == error_mark_node)
2918 /* See if this is a partial specialization. */
2919 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2920 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2921 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2923 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2926 /* For a friend, we want the context of the friend function, not
2927 the type of which it is a friend. */
2928 ctx = DECL_CONTEXT (decl);
2929 else if (CP_DECL_CONTEXT (decl)
2930 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2931 /* In the case of a virtual function, we want the class in which
2933 ctx = CP_DECL_CONTEXT (decl);
2935 /* Otherwise, if we're currently defining some class, the DECL
2936 is assumed to be a member of the class. */
2937 ctx = current_scope ();
2939 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2942 if (!DECL_CONTEXT (decl))
2943 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2945 /* See if this is a primary template. */
2946 primary = template_parm_scope_p ();
2950 if (DECL_CLASS_SCOPE_P (decl))
2951 member_template_p = true;
2952 if (current_lang_name == lang_name_c)
2953 error ("template with C linkage");
2954 else if (TREE_CODE (decl) == TYPE_DECL
2955 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2956 error ("template class without a name");
2957 else if (TREE_CODE (decl) == FUNCTION_DECL)
2959 if (DECL_DESTRUCTOR_P (decl))
2963 A destructor shall not be a member template. */
2964 error ("destructor %qD declared as member template", decl);
2965 return error_mark_node;
2967 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2968 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2969 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2970 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2971 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2972 == void_list_node)))
2974 /* [basic.stc.dynamic.allocation]
2976 An allocation function can be a function
2977 template. ... Template allocation functions shall
2978 have two or more parameters. */
2979 error ("invalid template declaration of %qD", decl);
2983 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2984 && CLASS_TYPE_P (TREE_TYPE (decl)))
2985 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx)))
2989 error ("template declaration of %q#D", decl);
2990 return error_mark_node;
2994 /* Check to see that the rules regarding the use of default
2995 arguments are not being violated. */
2996 check_default_tmpl_args (decl, current_template_parms,
2997 primary, is_partial);
3000 return process_partial_specialization (decl);
3002 args = current_template_args ();
3005 || TREE_CODE (ctx) == FUNCTION_DECL
3006 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3007 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3009 if (DECL_LANG_SPECIFIC (decl)
3010 && DECL_TEMPLATE_INFO (decl)
3011 && DECL_TI_TEMPLATE (decl))
3012 tmpl = DECL_TI_TEMPLATE (decl);
3013 /* If DECL is a TYPE_DECL for a class-template, then there won't
3014 be DECL_LANG_SPECIFIC. The information equivalent to
3015 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3016 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3017 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3018 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3020 /* Since a template declaration already existed for this
3021 class-type, we must be redeclaring it here. Make sure
3022 that the redeclaration is valid. */
3023 redeclare_class_template (TREE_TYPE (decl),
3024 current_template_parms);
3025 /* We don't need to create a new TEMPLATE_DECL; just use the
3026 one we already had. */
3027 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3031 tmpl = build_template_decl (decl, current_template_parms,
3035 if (DECL_LANG_SPECIFIC (decl)
3036 && DECL_TEMPLATE_SPECIALIZATION (decl))
3038 /* A specialization of a member template of a template
3040 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3041 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3042 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3048 tree a, t, current, parms;
3051 if (TREE_CODE (decl) == TYPE_DECL)
3053 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3054 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3055 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3056 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3057 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3060 error ("%qD does not declare a template type", decl);
3064 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3066 error ("template definition of non-template %q#D", decl);
3070 tmpl = DECL_TI_TEMPLATE (decl);
3072 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3073 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3074 && DECL_TEMPLATE_SPECIALIZATION (decl)
3075 && DECL_MEMBER_TEMPLATE_P (tmpl))
3079 /* The declaration is a specialization of a member
3080 template, declared outside the class. Therefore, the
3081 innermost template arguments will be NULL, so we
3082 replace them with the arguments determined by the
3083 earlier call to check_explicit_specialization. */
3084 args = DECL_TI_ARGS (decl);
3087 = build_template_decl (decl, current_template_parms,
3089 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3090 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3091 DECL_TI_TEMPLATE (decl) = new_tmpl;
3092 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3093 DECL_TEMPLATE_INFO (new_tmpl)
3094 = tree_cons (tmpl, args, NULL_TREE);
3096 register_specialization (new_tmpl,
3097 most_general_template (tmpl),
3102 /* Make sure the template headers we got make sense. */
3104 parms = DECL_TEMPLATE_PARMS (tmpl);
3105 i = TMPL_PARMS_DEPTH (parms);
3106 if (TMPL_ARGS_DEPTH (args) != i)
3108 error ("expected %d levels of template parms for %q#D, got %d",
3109 i, decl, TMPL_ARGS_DEPTH (args));
3112 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3114 a = TMPL_ARGS_LEVEL (args, i);
3115 t = INNERMOST_TEMPLATE_PARMS (parms);
3117 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3119 if (current == decl)
3120 error ("got %d template parameters for %q#D",
3121 TREE_VEC_LENGTH (a), decl);
3123 error ("got %d template parameters for %q#T",
3124 TREE_VEC_LENGTH (a), current);
3125 error (" but %d required", TREE_VEC_LENGTH (t));
3128 /* Perhaps we should also check that the parms are used in the
3129 appropriate qualifying scopes in the declarator? */
3131 if (current == decl)
3134 current = TYPE_CONTEXT (current);
3138 DECL_TEMPLATE_RESULT (tmpl) = decl;
3139 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3141 /* Push template declarations for global functions and types. Note
3142 that we do not try to push a global template friend declared in a
3143 template class; such a thing may well depend on the template
3144 parameters of the class. */
3145 if (new_template_p && !ctx
3146 && !(is_friend && template_class_depth (current_class_type) > 0))
3147 tmpl = pushdecl_namespace_level (tmpl);
3151 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3152 if (DECL_CONV_FN_P (tmpl))
3154 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3156 /* It is a conversion operator. See if the type converted to
3157 depends on innermost template operands. */
3159 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3161 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3165 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3166 back to its most general template. If TMPL is a specialization,
3167 ARGS may only have the innermost set of arguments. Add the missing
3168 argument levels if necessary. */
3169 if (DECL_TEMPLATE_INFO (tmpl))
3170 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3172 info = tree_cons (tmpl, args, NULL_TREE);
3174 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3176 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3177 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3178 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3179 /* Don't change the name if we've already set it up. */
3180 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3181 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3183 else if (DECL_LANG_SPECIFIC (decl))
3184 DECL_TEMPLATE_INFO (decl) = info;
3186 return DECL_TEMPLATE_RESULT (tmpl);
3190 push_template_decl (tree decl)
3192 return push_template_decl_real (decl, 0);
3195 /* Called when a class template TYPE is redeclared with the indicated
3196 template PARMS, e.g.:
3198 template <class T> struct S;
3199 template <class T> struct S {}; */
3202 redeclare_class_template (tree type, tree parms)
3208 if (!TYPE_TEMPLATE_INFO (type))
3210 error ("%qT is not a template type", type);
3214 tmpl = TYPE_TI_TEMPLATE (type);
3215 if (!PRIMARY_TEMPLATE_P (tmpl))
3216 /* The type is nested in some template class. Nothing to worry
3217 about here; there are no new template parameters for the nested
3221 parms = INNERMOST_TEMPLATE_PARMS (parms);
3222 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3224 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3226 cp_error_at ("previous declaration %qD", tmpl);
3227 error ("used %d template parameter%s instead of %d",
3228 TREE_VEC_LENGTH (tmpl_parms),
3229 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
3230 TREE_VEC_LENGTH (parms));
3234 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3236 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3237 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3238 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3239 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3241 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3243 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3244 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3245 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3247 cp_error_at ("template parameter %q#D", tmpl_parm);
3248 error ("redeclared here as %q#D", parm);
3252 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3254 /* We have in [temp.param]:
3256 A template-parameter may not be given default arguments
3257 by two different declarations in the same scope. */
3258 error ("redefinition of default argument for %q#D", parm);
3259 error ("%J original definition appeared here", tmpl_parm);
3263 if (parm_default != NULL_TREE)
3264 /* Update the previous template parameters (which are the ones
3265 that will really count) with the new default value. */
3266 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3267 else if (tmpl_default != NULL_TREE)
3268 /* Update the new parameters, too; they'll be used as the
3269 parameters for any members. */
3270 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3274 /* Simplify EXPR if it is a non-dependent expression. Returns the
3275 (possibly simplified) expression. */
3278 fold_non_dependent_expr (tree expr)
3280 /* If we're in a template, but EXPR isn't value dependent, simplify
3281 it. We're supposed to treat:
3283 template <typename T> void f(T[1 + 1]);
3284 template <typename T> void f(T[2]);
3286 as two declarations of the same function, for example. */
3287 if (processing_template_decl
3288 && !type_dependent_expression_p (expr)
3289 && !value_dependent_expression_p (expr))
3291 HOST_WIDE_INT saved_processing_template_decl;
3293 saved_processing_template_decl = processing_template_decl;
3294 processing_template_decl = 0;
3295 expr = tsubst_copy_and_build (expr,
3298 /*in_decl=*/NULL_TREE,
3299 /*function_p=*/false);
3300 processing_template_decl = saved_processing_template_decl;
3305 /* Attempt to convert the non-type template parameter EXPR to the
3306 indicated TYPE. If the conversion is successful, return the
3307 converted value. If the conversion is unsuccessful, return
3308 NULL_TREE if we issued an error message, or error_mark_node if we
3309 did not. We issue error messages for out-and-out bad template
3310 parameters, but not simply because the conversion failed, since we
3311 might be just trying to do argument deduction. Both TYPE and EXPR
3312 must be non-dependent. */
3315 convert_nontype_argument (tree type, tree expr)
3319 /* If we are in a template, EXPR may be non-dependent, but still
3320 have a syntactic, rather than semantic, form. For example, EXPR
3321 might be a SCOPE_REF, rather than the VAR_DECL to which the
3322 SCOPE_REF refers. Preserving the qualifying scope is necessary
3323 so that access checking can be performed when the template is
3324 instantiated -- but here we need the resolved form so that we can
3325 convert the argument. */
3326 expr = fold_non_dependent_expr (expr);
3327 expr_type = TREE_TYPE (expr);
3329 /* A template-argument for a non-type, non-template
3330 template-parameter shall be one of:
3332 --an integral constant-expression of integral or enumeration
3335 --the name of a non-type template-parameter; or
3337 --the name of an object or function with external linkage,
3338 including function templates and function template-ids but
3339 excluding non-static class members, expressed as id-expression;
3342 --the address of an object or function with external linkage,
3343 including function templates and function template-ids but
3344 excluding non-static class members, expressed as & id-expression
3345 where the & is optional if the name refers to a function or
3348 --a pointer to member expressed as described in _expr.unary.op_. */
3350 /* An integral constant-expression can include const variables or
3351 . enumerators. Simplify things by folding them to their values,
3352 unless we're about to bind the declaration to a reference
3354 if (INTEGRAL_TYPE_P (expr_type) && TREE_CODE (type) != REFERENCE_TYPE)
3357 tree const_expr = decl_constant_value (expr);
3358 /* In a template, the initializer for a VAR_DECL may not be
3359 marked as TREE_CONSTANT, in which case decl_constant_value
3360 will not return the initializer. Handle that special case
3362 if (expr == const_expr
3363 && DECL_INTEGRAL_CONSTANT_VAR_P (expr)
3364 /* DECL_INITIAL can be NULL if we are processing a
3365 variable initialized to an expression involving itself.
3366 We know it is initialized to a constant -- but not what
3368 && DECL_INITIAL (expr))
3369 const_expr = DECL_INITIAL (expr);
3370 if (expr == const_expr)
3372 expr = fold_non_dependent_expr (const_expr);
3375 if (is_overloaded_fn (expr))
3376 /* OK for now. We'll check that it has external linkage later.
3377 Check this first since if expr_type is the unknown_type_node
3378 we would otherwise complain below. */
3380 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3382 if (TREE_CODE (expr) != PTRMEM_CST)
3385 else if (TYPE_PTR_P (expr_type)
3386 || TREE_CODE (expr_type) == ARRAY_TYPE
3387 || TREE_CODE (type) == REFERENCE_TYPE
3388 /* If expr is the address of an overloaded function, we
3389 will get the unknown_type_node at this point. */
3390 || expr_type == unknown_type_node)
3396 if (TREE_CODE (expr_type) == ARRAY_TYPE
3397 || (TREE_CODE (type) == REFERENCE_TYPE
3398 && TREE_CODE (e) != ADDR_EXPR))
3402 if (TREE_CODE (e) != ADDR_EXPR)
3405 error ("%qE is not a valid template argument", expr);
3406 if (TYPE_PTR_P (expr_type))
3408 if (TREE_CODE (TREE_TYPE (expr_type)) == FUNCTION_TYPE)
3409 error ("it must be the address of a function with external linkage");
3411 error ("it must be the address of an object with external linkage");
3413 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3414 error ("it must be a pointer-to-member of the form %<&X::Y%>");
3419 referent = TREE_OPERAND (e, 0);
3420 STRIP_NOPS (referent);
3423 if (TREE_CODE (referent) == STRING_CST)
3425 error ("string literal %qE is not a valid template argument "
3426 "because it is the address of an object with static linkage",
3431 if (TREE_CODE (referent) == SCOPE_REF)
3432 referent = TREE_OPERAND (referent, 1);
3434 if (is_overloaded_fn (referent))
3435 /* We'll check that it has external linkage later. */
3437 else if (TREE_CODE (referent) != VAR_DECL)
3439 else if (!DECL_EXTERNAL_LINKAGE_P (referent))
3441 error ("address of non-extern %qE cannot be used as "
3442 "template argument", referent);
3443 return error_mark_node;
3446 else if (INTEGRAL_TYPE_P (expr_type) || TYPE_PTR_TO_MEMBER_P (expr_type))
3448 if (! TREE_CONSTANT (expr))
3451 error ("non-constant %qE cannot be used as template argument", expr);
3458 error ("type %qT cannot be used as a value for a non-type "
3459 "template-parameter", expr);
3460 else if (DECL_P (expr))
3461 error ("invalid use of %qD as a non-type template-argument", expr);
3463 error ("invalid use of %qE as a non-type template-argument", expr);
3468 switch (TREE_CODE (type))
3470 HOST_WIDE_INT saved_processing_template_decl;
3475 /* For a non-type template-parameter of integral or enumeration
3476 type, integral promotions (_conv.prom_) and integral
3477 conversions (_conv.integral_) are applied. */
3478 if (!INTEGRAL_TYPE_P (expr_type))
3479 return error_mark_node;
3481 /* [conv.integral] does not allow conversions between two different
3482 enumeration types. */
3483 if (TREE_CODE (type) == ENUMERAL_TYPE
3484 && TREE_CODE (expr_type) == ENUMERAL_TYPE
3485 && !same_type_ignoring_top_level_qualifiers_p (type, expr_type))
3486 return error_mark_node;
3488 /* It's safe to call digest_init in this case; we know we're
3489 just converting one integral constant expression to another.
3491 saved_processing_template_decl = processing_template_decl;
3492 processing_template_decl = 0;
3493 expr = digest_init (type, expr, (tree*) 0);
3494 processing_template_decl = saved_processing_template_decl;
3496 if (TREE_CODE (expr) != INTEGER_CST)
3497 /* Curiously, some TREE_CONSTANT integral expressions do not
3498 simplify to integer constants. For example, `3 % 0',
3499 remains a TRUNC_MOD_EXPR. */
3508 /* For a non-type template-parameter of type pointer to data
3509 member, qualification conversions (_conv.qual_) are
3511 e = perform_qualification_conversions (type, expr);
3512 if (TREE_CODE (e) == NOP_EXPR)
3513 /* The call to perform_qualification_conversions will
3514 insert a NOP_EXPR over EXPR to do express conversion,
3515 if necessary. But, that will confuse us if we use
3516 this (converted) template parameter to instantiate
3517 another template; then the thing will not look like a
3518 valid template argument. So, just make a new
3519 constant, of the appropriate type. */
3520 e = make_ptrmem_cst (type, PTRMEM_CST_MEMBER (expr));
3526 tree type_pointed_to = TREE_TYPE (type);
3528 if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE)
3530 /* For a non-type template-parameter of type pointer to
3531 function, only the function-to-pointer conversion
3532 (_conv.func_) is applied. If the template-argument
3533 represents a set of overloaded functions (or a pointer to
3534 such), the matching function is selected from the set
3539 if (TREE_CODE (expr) == ADDR_EXPR)
3540 fns = TREE_OPERAND (expr, 0);
3544 fn = instantiate_type (type_pointed_to, fns, tf_none);
3546 if (fn == error_mark_node)
3547 return error_mark_node;
3549 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3551 if (really_overloaded_fn (fns))
3552 return error_mark_node;
3557 expr = build_unary_op (ADDR_EXPR, fn, 0);
3559 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3564 /* For a non-type template-parameter of type pointer to
3565 object, qualification conversions (_conv.qual_) and the
3566 array-to-pointer conversion (_conv.array_) are applied.
3567 [Note: In particular, neither the null pointer conversion
3568 (_conv.ptr_) nor the derived-to-base conversion
3569 (_conv.ptr_) are applied. Although 0 is a valid
3570 template-argument for a non-type template-parameter of
3571 integral type, it is not a valid template-argument for a
3572 non-type template-parameter of pointer type.]
3574 The call to decay_conversion performs the
3575 array-to-pointer conversion, if appropriate. */
3576 expr = decay_conversion (expr);
3578 if (expr == error_mark_node)
3579 return error_mark_node;
3581 return perform_qualification_conversions (type, expr);
3586 case REFERENCE_TYPE:
3588 tree type_referred_to = TREE_TYPE (type);
3590 /* If this expression already has reference type, get the
3591 underlying object. */
3592 if (TREE_CODE (expr_type) == REFERENCE_TYPE)
3594 if (TREE_CODE (expr) == NOP_EXPR
3595 && TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR)
3597 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3598 expr = TREE_OPERAND (expr, 0);
3599 expr_type = TREE_TYPE (expr);
3602 if (TREE_CODE (type_referred_to) == FUNCTION_TYPE)
3604 /* For a non-type template-parameter of type reference to
3605 function, no conversions apply. If the
3606 template-argument represents a set of overloaded
3607 functions, the matching function is selected from the
3608 set (_over.over_). */
3611 fn = instantiate_type (type_referred_to, expr, tf_none);
3613 if (fn == error_mark_node)
3614 return error_mark_node;
3616 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3618 if (really_overloaded_fn (expr))
3619 /* Don't issue an error here; we might get a different
3620 function if the overloading had worked out
3622 return error_mark_node;
3627 gcc_assert (same_type_p (type_referred_to, TREE_TYPE (fn)));
3632 /* For a non-type template-parameter of type reference to
3633 object, no conversions apply. The type referred to by the
3634 reference may be more cv-qualified than the (otherwise
3635 identical) type of the template-argument. The
3636 template-parameter is bound directly to the
3637 template-argument, which must be an lvalue. */
3638 if (!same_type_p (TYPE_MAIN_VARIANT (expr_type),
3639 TYPE_MAIN_VARIANT (type_referred_to))
3640 || !at_least_as_qualified_p (type_referred_to,
3642 || !real_lvalue_p (expr))
3643 return error_mark_node;
3646 cxx_mark_addressable (expr);
3647 return build_nop (type, build_address (expr));
3653 gcc_assert (TYPE_PTRMEMFUNC_P (type));
3655 /* For a non-type template-parameter of type pointer to member
3656 function, no conversions apply. If the template-argument
3657 represents a set of overloaded member functions, the
3658 matching member function is selected from the set
3661 if (!TYPE_PTRMEMFUNC_P (expr_type) &&
3662 expr_type != unknown_type_node)
3663 return error_mark_node;
3665 if (TREE_CODE (expr) == PTRMEM_CST)
3667 /* A ptr-to-member constant. */
3668 if (!same_type_p (type, expr_type))
3669 return error_mark_node;
3674 if (TREE_CODE (expr) != ADDR_EXPR)
3675 return error_mark_node;
3677 expr = instantiate_type (type, expr, tf_none);
3679 if (expr == error_mark_node)
3680 return error_mark_node;
3682 if (!same_type_p (type, TREE_TYPE (expr)))
3683 return error_mark_node;
3690 /* All non-type parameters must have one of these types. */
3694 return error_mark_node;
3697 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3698 template template parameters. Both PARM_PARMS and ARG_PARMS are
3699 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3702 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3703 the case, then extra parameters must have default arguments.
3705 Consider the example:
3706 template <class T, class Allocator = allocator> class vector;
3707 template<template <class U> class TT> class C;
3709 C<vector> is a valid instantiation. PARM_PARMS for the above code
3710 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3711 T and Allocator) and OUTER_ARGS contains the argument that is used to
3712 substitute the TT parameter. */
3715 coerce_template_template_parms (tree parm_parms,
3717 tsubst_flags_t complain,
3721 int nparms, nargs, i;
3724 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3725 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3727 nparms = TREE_VEC_LENGTH (parm_parms);
3728 nargs = TREE_VEC_LENGTH (arg_parms);
3730 /* The rule here is opposite of coerce_template_parms. */
3733 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3736 for (i = 0; i < nparms; ++i)
3738 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3739 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3741 if (arg == NULL_TREE || arg == error_mark_node
3742 || parm == NULL_TREE || parm == error_mark_node)
3745 if (TREE_CODE (arg) != TREE_CODE (parm))
3748 switch (TREE_CODE (parm))
3754 /* We encounter instantiations of templates like
3755 template <template <template <class> class> class TT>
3758 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3759 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3761 if (!coerce_template_template_parms
3762 (parmparm, argparm, complain, in_decl, outer_args))
3768 /* The tsubst call is used to handle cases such as
3770 template <int> class C {};
3771 template <class T, template <T> class TT> class D {};
3774 i.e. the parameter list of TT depends on earlier parameters. */
3775 if (!dependent_type_p (TREE_TYPE (arg))
3777 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3789 /* Convert the indicated template ARG as necessary to match the
3790 indicated template PARM. Returns the converted ARG, or
3791 error_mark_node if the conversion was unsuccessful. Error and
3792 warning messages are issued under control of COMPLAIN. This
3793 conversion is for the Ith parameter in the parameter list. ARGS is
3794 the full set of template arguments deduced so far. */
3797 convert_template_argument (tree parm,
3800 tsubst_flags_t complain,
3806 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3808 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3810 if (TREE_CODE (arg) == TREE_LIST
3811 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3813 /* The template argument was the name of some
3814 member function. That's usually
3815 invalid, but static members are OK. In any
3816 case, grab the underlying fields/functions
3817 and issue an error later if required. */
3818 arg = TREE_VALUE (arg);
3819 TREE_TYPE (arg) = unknown_type_node;
3822 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3823 requires_type = (TREE_CODE (parm) == TYPE_DECL
3824 || requires_tmpl_type);
3826 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3827 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3828 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3829 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3832 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3833 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3834 arg = TYPE_STUB_DECL (arg);
3836 is_type = TYPE_P (arg) || is_tmpl_type;
3838 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3839 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3841 pedwarn ("to refer to a type member of a template parameter, "
3842 "use %<typename %E%>", arg);
3844 arg = make_typename_type (TREE_OPERAND (arg, 0),
3845 TREE_OPERAND (arg, 1),
3846 complain & tf_error);
3849 if (is_type != requires_type)
3853 if (complain & tf_error)
3855 error ("type/value mismatch at argument %d in template "
3856 "parameter list for %qD",
3859 error (" expected a constant of type %qT, got %qT",
3861 (is_tmpl_type ? DECL_NAME (arg) : arg));
3862 else if (requires_tmpl_type)
3863 error (" expected a class template, got %qE", arg);
3865 error (" expected a type, got %qE", arg);
3868 return error_mark_node;
3870 if (is_tmpl_type ^ requires_tmpl_type)
3872 if (in_decl && (complain & tf_error))
3874 error ("type/value mismatch at argument %d in template "
3875 "parameter list for %qD",
3878 error (" expected a type, got %qT", DECL_NAME (arg));
3880 error (" expected a class template, got %qT", arg);
3882 return error_mark_node;
3887 if (requires_tmpl_type)
3889 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3890 /* The number of argument required is not known yet.
3891 Just accept it for now. */
3892 val = TREE_TYPE (arg);
3895 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3896 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3898 if (coerce_template_template_parms (parmparm, argparm,
3904 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3906 if (val != error_mark_node
3907 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3908 val = TREE_TYPE (val);
3912 if (in_decl && (complain & tf_error))
3914 error ("type/value mismatch at argument %d in "
3915 "template parameter list for %qD",
3917 error (" expected a template of type %qD, got %qD",
3921 val = error_mark_node;
3930 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3932 if (invalid_nontype_parm_type_p (t, complain))
3933 return error_mark_node;
3935 if (!uses_template_parms (arg) && !uses_template_parms (t))
3936 /* We used to call digest_init here. However, digest_init
3937 will report errors, which we don't want when complain
3938 is zero. More importantly, digest_init will try too
3939 hard to convert things: for example, `0' should not be
3940 converted to pointer type at this point according to
3941 the standard. Accepting this is not merely an
3942 extension, since deciding whether or not these
3943 conversions can occur is part of determining which
3944 function template to call, or whether a given explicit
3945 argument specification is valid. */
3946 val = convert_nontype_argument (t, arg);
3950 if (val == NULL_TREE)
3951 val = error_mark_node;
3952 else if (val == error_mark_node && (complain & tf_error))
3953 error ("could not convert template argument %qE to %qT", arg, t);
3959 /* Convert all template arguments to their appropriate types, and
3960 return a vector containing the innermost resulting template
3961 arguments. If any error occurs, return error_mark_node. Error and
3962 warning messages are issued under control of COMPLAIN.
3964 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3965 provided in ARGLIST, or else trailing parameters must have default
3966 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3967 deduction for any unspecified trailing arguments. */
3970 coerce_template_parms (tree parms,
3973 tsubst_flags_t complain,
3974 int require_all_arguments)
3976 int nparms, nargs, i, lost = 0;
3979 tree new_inner_args;
3981 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3982 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3983 nparms = TREE_VEC_LENGTH (parms);
3987 && require_all_arguments
3988 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3990 if (complain & tf_error)
3992 error ("wrong number of template arguments (%d, should be %d)",
3996 cp_error_at ("provided for %qD", in_decl);
3999 return error_mark_node;
4002 new_inner_args = make_tree_vec (nparms);
4003 new_args = add_outermost_template_args (args, new_inner_args);
4004 for (i = 0; i < nparms; i++)
4009 /* Get the Ith template parameter. */
4010 parm = TREE_VEC_ELT (parms, i);
4012 /* Calculate the Ith argument. */
4014 arg = TREE_VEC_ELT (inner_args, i);
4015 else if (require_all_arguments)
4016 /* There must be a default arg in this case. */
4017 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4023 if (arg == error_mark_node)
4024 error ("template argument %d is invalid", i + 1);
4026 arg = convert_template_argument (TREE_VALUE (parm),
4027 arg, new_args, complain, i,
4030 if (arg == error_mark_node)
4032 TREE_VEC_ELT (new_inner_args, i) = arg;
4036 return error_mark_node;
4038 return new_inner_args;
4041 /* Returns 1 if template args OT and NT are equivalent. */
4044 template_args_equal (tree ot, tree nt)
4049 if (TREE_CODE (nt) == TREE_VEC)
4050 /* For member templates */
4051 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4052 else if (TYPE_P (nt))
4053 return TYPE_P (ot) && same_type_p (ot, nt);
4054 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4057 return cp_tree_equal (ot, nt);
4060 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4061 of template arguments. Returns 0 otherwise. */
4064 comp_template_args (tree oldargs, tree newargs)
4068 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4071 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4073 tree nt = TREE_VEC_ELT (newargs, i);
4074 tree ot = TREE_VEC_ELT (oldargs, i);
4076 if (! template_args_equal (ot, nt))
4082 /* Given class template name and parameter list, produce a user-friendly name
4083 for the instantiation. */
4086 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4088 static struct obstack scratch_obstack;
4089 static char *scratch_firstobj;
4092 if (!scratch_firstobj)
4093 gcc_obstack_init (&scratch_obstack);
4095 obstack_free (&scratch_obstack, scratch_firstobj);
4096 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4098 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4099 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4103 nparms = TREE_VEC_LENGTH (parms);
4104 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4105 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4106 for (i = 0; i < nparms; i++)
4108 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4109 tree arg = TREE_VEC_ELT (arglist, i);
4114 if (TREE_CODE (parm) == TYPE_DECL)
4116 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4119 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4121 if (TREE_CODE (arg) == TEMPLATE_DECL)
4123 /* Already substituted with real template. Just output
4124 the template name here */
4125 tree context = DECL_CONTEXT (arg);
4128 /* The template may be defined in a namespace, or
4129 may be a member template. */
4130 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4131 || CLASS_TYPE_P (context));
4132 cat (decl_as_string (DECL_CONTEXT (arg),
4133 TFF_PLAIN_IDENTIFIER));
4136 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4139 /* Output the parameter declaration. */
4140 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4144 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4146 /* No need to check arglist against parmlist here; we did that
4147 in coerce_template_parms, called from lookup_template_class. */
4148 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4151 char *bufp = obstack_next_free (&scratch_obstack);
4153 while (bufp[offset - 1] == ' ')
4155 obstack_blank_fast (&scratch_obstack, offset);
4157 /* B<C<char> >, not B<C<char>> */
4158 if (bufp[offset - 1] == '>')
4163 return (char *) obstack_base (&scratch_obstack);
4167 classtype_mangled_name (tree t)
4169 if (CLASSTYPE_TEMPLATE_INFO (t)
4170 /* Specializations have already had their names set up in
4171 lookup_template_class. */
4172 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4174 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4176 /* For non-primary templates, the template parameters are
4177 implicit from their surrounding context. */
4178 if (PRIMARY_TEMPLATE_P (tmpl))
4180 tree name = DECL_NAME (tmpl);
4181 char *mangled_name = mangle_class_name_for_template
4182 (IDENTIFIER_POINTER (name),
4183 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4184 CLASSTYPE_TI_ARGS (t));
4185 tree id = get_identifier (mangled_name);
4186 IDENTIFIER_TEMPLATE (id) = name;
4191 return TYPE_IDENTIFIER (t);
4195 add_pending_template (tree d)
4197 tree ti = (TYPE_P (d)
4198 ? CLASSTYPE_TEMPLATE_INFO (d)
4199 : DECL_TEMPLATE_INFO (d));
4203 if (TI_PENDING_TEMPLATE_FLAG (ti))
4206 /* We are called both from instantiate_decl, where we've already had a
4207 tinst_level pushed, and instantiate_template, where we haven't.
4209 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4212 push_tinst_level (d);
4214 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4215 if (last_pending_template)
4216 TREE_CHAIN (last_pending_template) = pt;
4218 pending_templates = pt;
4220 last_pending_template = pt;
4222 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4229 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4230 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4231 documentation for TEMPLATE_ID_EXPR. */
4234 lookup_template_function (tree fns, tree arglist)
4238 if (fns == error_mark_node || arglist == error_mark_node)
4239 return error_mark_node;
4241 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4242 if (fns == NULL_TREE
4243 || TREE_CODE (fns) == FUNCTION_DECL)
4245 error ("non-template used as template");
4246 return error_mark_node;
4249 gcc_assert (TREE_CODE (fns) == TEMPLATE_DECL
4250 || TREE_CODE (fns) == OVERLOAD
4252 || TREE_CODE (fns) == IDENTIFIER_NODE);
4254 if (BASELINK_P (fns))
4256 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4258 BASELINK_FUNCTIONS (fns),
4263 type = TREE_TYPE (fns);
4264 if (TREE_CODE (fns) == OVERLOAD || !type)
4265 type = unknown_type_node;
4267 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4270 /* Within the scope of a template class S<T>, the name S gets bound
4271 (in build_self_reference) to a TYPE_DECL for the class, not a
4272 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4273 or one of its enclosing classes, and that type is a template,
4274 return the associated TEMPLATE_DECL. Otherwise, the original
4275 DECL is returned. */
4278 maybe_get_template_decl_from_type_decl (tree decl)
4280 return (decl != NULL_TREE
4281 && TREE_CODE (decl) == TYPE_DECL
4282 && DECL_ARTIFICIAL (decl)
4283 && CLASS_TYPE_P (TREE_TYPE (decl))
4284 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4285 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4288 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4289 parameters, find the desired type.
4291 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4293 IN_DECL, if non-NULL, is the template declaration we are trying to
4296 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4297 the class we are looking up.
4299 Issue error and warning messages under control of COMPLAIN.
4301 If the template class is really a local class in a template
4302 function, then the FUNCTION_CONTEXT is the function in which it is
4303 being instantiated. */
4306 lookup_template_class (tree d1,
4311 tsubst_flags_t complain)
4313 tree template = NULL_TREE, parmlist;
4316 timevar_push (TV_NAME_LOOKUP);
4318 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4320 tree value = innermost_non_namespace_value (d1);
4321 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4326 push_decl_namespace (context);
4327 template = lookup_name (d1, /*prefer_type=*/0);
4328 template = maybe_get_template_decl_from_type_decl (template);
4330 pop_decl_namespace ();
4333 context = DECL_CONTEXT (template);
4335 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4337 tree type = TREE_TYPE (d1);
4339 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4340 an implicit typename for the second A. Deal with it. */
4341 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4342 type = TREE_TYPE (type);
4344 if (CLASSTYPE_TEMPLATE_INFO (type))
4346 template = CLASSTYPE_TI_TEMPLATE (type);
4347 d1 = DECL_NAME (template);
4350 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4351 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4353 template = TYPE_TI_TEMPLATE (d1);
4354 d1 = DECL_NAME (template);
4356 else if (TREE_CODE (d1) == TEMPLATE_DECL
4357 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4360 d1 = DECL_NAME (template);
4361 context = DECL_CONTEXT (template);
4364 /* Issue an error message if we didn't find a template. */
4367 if (complain & tf_error)
4368 error ("%qT is not a template", d1);
4369 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4372 if (TREE_CODE (template) != TEMPLATE_DECL
4373 /* Make sure it's a user visible template, if it was named by
4375 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4376 && !PRIMARY_TEMPLATE_P (template)))
4378 if (complain & tf_error)
4380 error ("non-template type %qT used as a template", d1);
4382 cp_error_at ("for template declaration %qD", in_decl);
4384 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4387 complain &= ~tf_user;
4389 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4391 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4392 template arguments */
4397 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4399 /* Consider an example where a template template parameter declared as
4401 template <class T, class U = std::allocator<T> > class TT
4403 The template parameter level of T and U are one level larger than
4404 of TT. To proper process the default argument of U, say when an
4405 instantiation `TT<int>' is seen, we need to build the full
4406 arguments containing {int} as the innermost level. Outer levels,
4407 available when not appearing as default template argument, can be
4408 obtained from `current_template_args ()'.
4410 Suppose that TT is later substituted with std::vector. The above
4411 instantiation is `TT<int, std::allocator<T> >' with TT at
4412 level 1, and T at level 2, while the template arguments at level 1
4413 becomes {std::vector} and the inner level 2 is {int}. */
4415 if (current_template_parms)
4416 arglist = add_to_template_args (current_template_args (), arglist);
4418 arglist2 = coerce_template_parms (parmlist, arglist, template,
4419 complain, /*require_all_args=*/1);
4420 if (arglist2 == error_mark_node
4421 || (!uses_template_parms (arglist2)
4422 && check_instantiated_args (template, arglist2, complain)))
4423 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4425 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4426 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4430 tree template_type = TREE_TYPE (template);
4433 tree found = NULL_TREE;
4436 int is_partial_instantiation;
4438 gen_tmpl = most_general_template (template);
4439 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4440 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4441 arg_depth = TMPL_ARGS_DEPTH (arglist);
4443 if (arg_depth == 1 && parm_depth > 1)
4445 /* We've been given an incomplete set of template arguments.
4448 template <class T> struct S1 {
4449 template <class U> struct S2 {};
4450 template <class U> struct S2<U*> {};
4453 we will be called with an ARGLIST of `U*', but the
4454 TEMPLATE will be `template <class T> template
4455 <class U> struct S1<T>::S2'. We must fill in the missing
4458 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4460 arg_depth = TMPL_ARGS_DEPTH (arglist);
4463 /* Now we should have enough arguments. */
4464 gcc_assert (parm_depth == arg_depth);
4466 /* From here on, we're only interested in the most general
4468 template = gen_tmpl;
4470 /* Calculate the BOUND_ARGS. These will be the args that are
4471 actually tsubst'd into the definition to create the
4475 /* We have multiple levels of arguments to coerce, at once. */
4477 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4479 tree bound_args = make_tree_vec (parm_depth);
4481 for (i = saved_depth,
4482 t = DECL_TEMPLATE_PARMS (template);
4483 i > 0 && t != NULL_TREE;
4484 --i, t = TREE_CHAIN (t))
4486 tree a = coerce_template_parms (TREE_VALUE (t),
4488 complain, /*require_all_args=*/1);
4490 /* Don't process further if one of the levels fails. */
4491 if (a == error_mark_node)
4493 /* Restore the ARGLIST to its full size. */
4494 TREE_VEC_LENGTH (arglist) = saved_depth;
4495 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4498 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4500 /* We temporarily reduce the length of the ARGLIST so
4501 that coerce_template_parms will see only the arguments
4502 corresponding to the template parameters it is
4504 TREE_VEC_LENGTH (arglist)--;
4507 /* Restore the ARGLIST to its full size. */
4508 TREE_VEC_LENGTH (arglist) = saved_depth;
4510 arglist = bound_args;
4514 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4515 INNERMOST_TEMPLATE_ARGS (arglist),
4517 complain, /*require_all_args=*/1);
4519 if (arglist == error_mark_node)
4520 /* We were unable to bind the arguments. */
4521 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4523 /* In the scope of a template class, explicit references to the
4524 template class refer to the type of the template, not any
4525 instantiation of it. For example, in:
4527 template <class T> class C { void f(C<T>); }
4529 the `C<T>' is just the same as `C'. Outside of the
4530 class, however, such a reference is an instantiation. */
4531 if (comp_template_args (TYPE_TI_ARGS (template_type),
4534 found = template_type;
4536 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4540 for (ctx = current_class_type;
4541 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4543 ? TYPE_CONTEXT (ctx)
4544 : DECL_CONTEXT (ctx)))
4545 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4548 /* We're not in the scope of the class, so the
4549 TEMPLATE_TYPE is not the type we want after all. */
4555 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4557 /* If we already have this specialization, return it. */
4558 found = retrieve_specialization (template, arglist,
4559 /*class_specializations_p=*/false);
4561 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4563 /* This type is a "partial instantiation" if any of the template
4564 arguments still involve template parameters. Note that we set
4565 IS_PARTIAL_INSTANTIATION for partial specializations as
4567 is_partial_instantiation = uses_template_parms (arglist);
4569 /* If the deduced arguments are invalid, then the binding
4571 if (!is_partial_instantiation
4572 && check_instantiated_args (template,
4573 INNERMOST_TEMPLATE_ARGS (arglist),
4575 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4577 if (!is_partial_instantiation
4578 && !PRIMARY_TEMPLATE_P (template)
4579 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4581 found = xref_tag_from_type (TREE_TYPE (template),
4582 DECL_NAME (template),
4584 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4587 context = tsubst (DECL_CONTEXT (template), arglist,
4590 context = global_namespace;
4592 /* Create the type. */
4593 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4595 if (!is_partial_instantiation)
4597 set_current_access_from_decl (TYPE_NAME (template_type));
4598 t = start_enum (TYPE_IDENTIFIER (template_type));
4601 /* We don't want to call start_enum for this type, since
4602 the values for the enumeration constants may involve
4603 template parameters. And, no one should be interested
4604 in the enumeration constants for such a type. */
4605 t = make_node (ENUMERAL_TYPE);
4609 t = make_aggr_type (TREE_CODE (template_type));
4610 CLASSTYPE_DECLARED_CLASS (t)
4611 = CLASSTYPE_DECLARED_CLASS (template_type);
4612 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4613 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4615 /* A local class. Make sure the decl gets registered properly. */
4616 if (context == current_function_decl)
4617 pushtag (DECL_NAME (template), t, 0);
4620 /* If we called start_enum or pushtag above, this information
4621 will already be set up. */
4624 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4626 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4627 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4628 TYPE_STUB_DECL (t) = type_decl;
4629 DECL_SOURCE_LOCATION (type_decl)
4630 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4633 type_decl = TYPE_NAME (t);
4635 TREE_PRIVATE (type_decl)
4636 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4637 TREE_PROTECTED (type_decl)
4638 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4640 /* Set up the template information. We have to figure out which
4641 template is the immediate parent if this is a full
4643 if (parm_depth == 1 || is_partial_instantiation
4644 || !PRIMARY_TEMPLATE_P (template))
4645 /* This case is easy; there are no member templates involved. */
4649 /* This is a full instantiation of a member template. Look
4650 for a partial instantiation of which this is an instance. */
4652 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4653 found; found = TREE_CHAIN (found))
4656 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4658 /* We only want partial instantiations, here, not
4659 specializations or full instantiations. */
4660 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4661 || !uses_template_parms (TREE_VALUE (found)))
4664 /* Temporarily reduce by one the number of levels in the
4665 ARGLIST and in FOUND so as to avoid comparing the
4666 last set of arguments. */
4667 TREE_VEC_LENGTH (arglist)--;
4668 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4670 /* See if the arguments match. If they do, then TMPL is
4671 the partial instantiation we want. */
4672 success = comp_template_args (TREE_PURPOSE (found), arglist);
4674 /* Restore the argument vectors to their full size. */
4675 TREE_VEC_LENGTH (arglist)++;
4676 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4687 /* There was no partial instantiation. This happens
4688 where C<T> is a member template of A<T> and it's used
4691 template <typename T> struct B { A<T>::C<int> m; };
4694 Create the partial instantiation.
4696 TREE_VEC_LENGTH (arglist)--;
4697 found = tsubst (template, arglist, complain, NULL_TREE);
4698 TREE_VEC_LENGTH (arglist)++;
4702 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4703 DECL_TEMPLATE_INSTANTIATIONS (template)
4704 = tree_cons (arglist, t,
4705 DECL_TEMPLATE_INSTANTIATIONS (template));
4707 if (TREE_CODE (t) == ENUMERAL_TYPE
4708 && !is_partial_instantiation)
4709 /* Now that the type has been registered on the instantiations
4710 list, we set up the enumerators. Because the enumeration
4711 constants may involve the enumeration type itself, we make
4712 sure to register the type first, and then create the
4713 constants. That way, doing tsubst_expr for the enumeration
4714 constants won't result in recursive calls here; we'll find
4715 the instantiation and exit above. */
4716 tsubst_enum (template_type, t, arglist);
4718 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4720 if (TREE_CODE (t) != ENUMERAL_TYPE)
4721 DECL_NAME (type_decl) = classtype_mangled_name (t);
4722 if (is_partial_instantiation)
4723 /* If the type makes use of template parameters, the
4724 code that generates debugging information will crash. */
4725 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4727 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4729 timevar_pop (TV_NAME_LOOKUP);
4736 struct pointer_set_t *visited;
4739 /* Called from for_each_template_parm via walk_tree. */
4742 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4745 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4746 tree_fn_t fn = pfd->fn;
4747 void *data = pfd->data;
4750 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4751 return error_mark_node;
4753 switch (TREE_CODE (t))
4756 if (TYPE_PTRMEMFUNC_P (t))
4762 if (!TYPE_TEMPLATE_INFO (t))
4764 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4765 fn, data, pfd->visited))
4766 return error_mark_node;
4770 /* Since we're not going to walk subtrees, we have to do this
4772 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4774 return error_mark_node;
4778 /* Check the return type. */
4779 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4780 return error_mark_node;
4782 /* Check the parameter types. Since default arguments are not
4783 instantiated until they are needed, the TYPE_ARG_TYPES may
4784 contain expressions that involve template parameters. But,
4785 no-one should be looking at them yet. And, once they're
4786 instantiated, they don't contain template parameters, so
4787 there's no point in looking at them then, either. */
4791 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4792 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4794 return error_mark_node;
4796 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4797 want walk_tree walking into them itself. */
4803 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4805 return error_mark_node;
4810 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4811 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4813 return error_mark_node;
4818 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4819 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4821 return error_mark_node;
4822 if (DECL_CONTEXT (t)
4823 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4825 return error_mark_node;
4828 case BOUND_TEMPLATE_TEMPLATE_PARM:
4829 /* Record template parameters such as `T' inside `TT<T>'. */
4830 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4831 return error_mark_node;
4834 case TEMPLATE_TEMPLATE_PARM:
4835 case TEMPLATE_TYPE_PARM:
4836 case TEMPLATE_PARM_INDEX:
4837 if (fn && (*fn)(t, data))
4838 return error_mark_node;
4840 return error_mark_node;
4844 /* A template template parameter is encountered. */
4845 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4846 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4847 return error_mark_node;
4849 /* Already substituted template template parameter */
4855 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4856 data, pfd->visited))
4857 return error_mark_node;
4861 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4862 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4863 (TREE_TYPE (t)), fn, data,
4865 return error_mark_node;
4870 /* If there's no type, then this thing must be some expression
4871 involving template parameters. */
4872 if (!fn && !TREE_TYPE (t))
4873 return error_mark_node;
4878 case REINTERPRET_CAST_EXPR:
4879 case CONST_CAST_EXPR:
4880 case STATIC_CAST_EXPR:
4881 case DYNAMIC_CAST_EXPR:
4885 case PSEUDO_DTOR_EXPR:
4887 return error_mark_node;
4891 /* If we do not handle this case specially, we end up walking
4892 the BINFO hierarchy, which is circular, and therefore
4893 confuses walk_tree. */
4895 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4897 return error_mark_node;
4904 /* We didn't find any template parameters we liked. */
4908 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4909 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4910 call FN with the parameter and the DATA.
4911 If FN returns nonzero, the iteration is terminated, and
4912 for_each_template_parm returns 1. Otherwise, the iteration
4913 continues. If FN never returns a nonzero value, the value
4914 returned by for_each_template_parm is 0. If FN is NULL, it is
4915 considered to be the function which always returns 1. */
4918 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4919 struct pointer_set_t *visited)
4921 struct pair_fn_data pfd;
4928 /* Walk the tree. (Conceptually, we would like to walk without
4929 duplicates, but for_each_template_parm_r recursively calls
4930 for_each_template_parm, so we would need to reorganize a fair
4931 bit to use walk_tree_without_duplicates, so we keep our own
4934 pfd.visited = visited;
4936 pfd.visited = pointer_set_create ();
4937 result = walk_tree (&t,
4938 for_each_template_parm_r,
4940 pfd.visited) != NULL_TREE;
4945 pointer_set_destroy (pfd.visited);
4952 /* Returns true if T depends on any template parameter. */
4955 uses_template_parms (tree t)
4958 int saved_processing_template_decl;
4960 saved_processing_template_decl = processing_template_decl;
4961 if (!saved_processing_template_decl)
4962 processing_template_decl = 1;
4964 dependent_p = dependent_type_p (t);
4965 else if (TREE_CODE (t) == TREE_VEC)
4966 dependent_p = any_dependent_template_arguments_p (t);
4967 else if (TREE_CODE (t) == TREE_LIST)
4968 dependent_p = (uses_template_parms (TREE_VALUE (t))
4969 || uses_template_parms (TREE_CHAIN (t)));
4972 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4973 || TREE_CODE (t) == OVERLOAD
4974 || TREE_CODE (t) == BASELINK
4975 || CONSTANT_CLASS_P (t))
4976 dependent_p = (type_dependent_expression_p (t)
4977 || value_dependent_expression_p (t));
4980 gcc_assert (t == error_mark_node);
4981 dependent_p = false;
4984 processing_template_decl = saved_processing_template_decl;
4989 /* Returns true if T depends on any template parameter with level LEVEL. */
4992 uses_template_parms_level (tree t, int level)
4994 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4997 static int tinst_depth;
4998 extern int max_tinst_depth;
4999 #ifdef GATHER_STATISTICS
5002 static int tinst_level_tick;
5003 static int last_template_error_tick;
5005 /* We're starting to instantiate D; record the template instantiation context
5006 for diagnostics and to restore it later. */
5009 push_tinst_level (tree d)
5013 if (tinst_depth >= max_tinst_depth)
5015 /* If the instantiation in question still has unbound template parms,
5016 we don't really care if we can't instantiate it, so just return.
5017 This happens with base instantiation for implicit `typename'. */
5018 if (uses_template_parms (d))
5021 last_template_error_tick = tinst_level_tick;
5022 error ("template instantiation depth exceeds maximum of %d (use "
5023 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5024 max_tinst_depth, d);
5026 print_instantiation_context ();
5031 new = make_tinst_level (d, input_location);
5032 TREE_CHAIN (new) = current_tinst_level;
5033 current_tinst_level = new;
5036 #ifdef GATHER_STATISTICS
5037 if (tinst_depth > depth_reached)
5038 depth_reached = tinst_depth;
5045 /* We're done instantiating this template; return to the instantiation
5049 pop_tinst_level (void)
5051 tree old = current_tinst_level;
5053 /* Restore the filename and line number stashed away when we started
5054 this instantiation. */
5055 input_location = TINST_LOCATION (old);
5056 current_tinst_level = TREE_CHAIN (old);
5061 /* We're instantiating a deferred template; restore the template
5062 instantiation context in which the instantiation was requested, which
5063 is one step out from LEVEL. */
5066 reopen_tinst_level (tree level)
5071 for (t = level; t; t = TREE_CHAIN (t))
5074 current_tinst_level = level;
5078 /* Return the outermost template instantiation context, for use with
5079 -falt-external-templates. */
5082 tinst_for_decl (void)
5084 tree p = current_tinst_level;
5087 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
5092 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5093 vector of template arguments, as for tsubst.
5095 Returns an appropriate tsubst'd friend declaration. */
5098 tsubst_friend_function (tree decl, tree args)
5101 location_t saved_loc = input_location;
5103 input_location = DECL_SOURCE_LOCATION (decl);
5105 if (TREE_CODE (decl) == FUNCTION_DECL
5106 && DECL_TEMPLATE_INSTANTIATION (decl)
5107 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5108 /* This was a friend declared with an explicit template
5109 argument list, e.g.:
5113 to indicate that f was a template instantiation, not a new
5114 function declaration. Now, we have to figure out what
5115 instantiation of what template. */
5117 tree template_id, arglist, fns;
5120 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5122 /* Friend functions are looked up in the containing namespace scope.
5123 We must enter that scope, to avoid finding member functions of the
5124 current cless with same name. */
5125 push_nested_namespace (ns);
5126 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5127 tf_error | tf_warning, NULL_TREE);
5128 pop_nested_namespace (ns);
5129 arglist = tsubst (DECL_TI_ARGS (decl), args,
5130 tf_error | tf_warning, NULL_TREE);
5131 template_id = lookup_template_function (fns, arglist);
5133 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5134 tmpl = determine_specialization (template_id, new_friend,
5136 /*need_member_template=*/0,
5137 TREE_VEC_LENGTH (args));
5138 new_friend = instantiate_template (tmpl, new_args, tf_error);
5142 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5144 /* The NEW_FRIEND will look like an instantiation, to the
5145 compiler, but is not an instantiation from the point of view of
5146 the language. For example, we might have had:
5148 template <class T> struct S {
5149 template <class U> friend void f(T, U);
5152 Then, in S<int>, template <class U> void f(int, U) is not an
5153 instantiation of anything. */
5154 if (new_friend == error_mark_node)
5155 return error_mark_node;
5157 DECL_USE_TEMPLATE (new_friend) = 0;
5158 if (TREE_CODE (decl) == TEMPLATE_DECL)
5160 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5161 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5162 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5165 /* The mangled name for the NEW_FRIEND is incorrect. The function
5166 is not a template instantiation and should not be mangled like
5167 one. Therefore, we forget the mangling here; we'll recompute it
5168 later if we need it. */
5169 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5171 SET_DECL_RTL (new_friend, NULL_RTX);
5172 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5175 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5178 tree new_friend_template_info;
5179 tree new_friend_result_template_info;
5181 int new_friend_is_defn;
5183 /* We must save some information from NEW_FRIEND before calling
5184 duplicate decls since that function will free NEW_FRIEND if
5186 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5187 new_friend_is_defn =
5188 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5189 (template_for_substitution (new_friend)))
5191 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5193 /* This declaration is a `primary' template. */
5194 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5196 new_friend_result_template_info
5197 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5200 new_friend_result_template_info = NULL_TREE;
5202 /* Inside pushdecl_namespace_level, we will push into the
5203 current namespace. However, the friend function should go
5204 into the namespace of the template. */
5205 ns = decl_namespace_context (new_friend);
5206 push_nested_namespace (ns);
5207 old_decl = pushdecl_namespace_level (new_friend);
5208 pop_nested_namespace (ns);
5210 if (old_decl != new_friend)
5212 /* This new friend declaration matched an existing
5213 declaration. For example, given:
5215 template <class T> void f(T);
5216 template <class U> class C {
5217 template <class T> friend void f(T) {}
5220 the friend declaration actually provides the definition
5221 of `f', once C has been instantiated for some type. So,
5222 old_decl will be the out-of-class template declaration,
5223 while new_friend is the in-class definition.
5225 But, if `f' was called before this point, the
5226 instantiation of `f' will have DECL_TI_ARGS corresponding
5227 to `T' but not to `U', references to which might appear
5228 in the definition of `f'. Previously, the most general
5229 template for an instantiation of `f' was the out-of-class
5230 version; now it is the in-class version. Therefore, we
5231 run through all specialization of `f', adding to their
5232 DECL_TI_ARGS appropriately. In particular, they need a
5233 new set of outer arguments, corresponding to the
5234 arguments for this class instantiation.
5236 The same situation can arise with something like this:
5239 template <class T> class C {
5243 when `C<int>' is instantiated. Now, `f(int)' is defined
5246 if (!new_friend_is_defn)
5247 /* On the other hand, if the in-class declaration does
5248 *not* provide a definition, then we don't want to alter
5249 existing definitions. We can just leave everything
5254 /* Overwrite whatever template info was there before, if
5255 any, with the new template information pertaining to
5257 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5259 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5260 reregister_specialization (new_friend,
5261 most_general_template (old_decl),
5266 tree new_friend_args;
5268 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5269 = new_friend_result_template_info;
5271 new_friend_args = TI_ARGS (new_friend_template_info);
5272 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5276 tree spec = TREE_VALUE (t);
5279 = add_outermost_template_args (new_friend_args,
5280 DECL_TI_ARGS (spec));
5283 /* Now, since specializations are always supposed to
5284 hang off of the most general template, we must move
5286 t = most_general_template (old_decl);
5289 DECL_TEMPLATE_SPECIALIZATIONS (t)
5290 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5291 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5292 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5297 /* The information from NEW_FRIEND has been merged into OLD_DECL
5298 by duplicate_decls. */
5299 new_friend = old_decl;
5302 else if (COMPLETE_TYPE_P (DECL_CONTEXT (new_friend)))
5304 /* Check to see that the declaration is really present, and,
5305 possibly obtain an improved declaration. */
5306 tree fn = check_classfn (DECL_CONTEXT (new_friend),
5307 new_friend, NULL_TREE);
5314 input_location = saved_loc;
5318 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5319 template arguments, as for tsubst.
5321 Returns an appropriate tsubst'd friend type or error_mark_node on
5325 tsubst_friend_class (tree friend_tmpl, tree args)
5331 context = DECL_CONTEXT (friend_tmpl);
5335 if (TREE_CODE (context) == NAMESPACE_DECL)
5336 push_nested_namespace (context);
5338 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5341 /* First, we look for a class template. */
5342 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5344 /* But, if we don't find one, it might be because we're in a
5345 situation like this:
5353 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5354 for `S<int>', not the TEMPLATE_DECL. */
5355 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5357 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5358 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5361 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5363 /* The friend template has already been declared. Just
5364 check to see that the declarations match, and install any new
5365 default parameters. We must tsubst the default parameters,
5366 of course. We only need the innermost template parameters
5367 because that is all that redeclare_class_template will look
5369 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5370 > TMPL_ARGS_DEPTH (args))
5373 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5374 args, tf_error | tf_warning);
5375 redeclare_class_template (TREE_TYPE (tmpl), parms);
5378 friend_type = TREE_TYPE (tmpl);
5382 /* The friend template has not already been declared. In this
5383 case, the instantiation of the template class will cause the
5384 injection of this template into the global scope. */
5385 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5387 /* The new TMPL is not an instantiation of anything, so we
5388 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5389 the new type because that is supposed to be the corresponding
5390 template decl, i.e., TMPL. */
5391 DECL_USE_TEMPLATE (tmpl) = 0;
5392 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5393 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5394 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5395 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5397 /* Inject this template into the global scope. */
5398 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5403 if (TREE_CODE (context) == NAMESPACE_DECL)
5404 pop_nested_namespace (context);
5406 pop_nested_class ();
5412 /* Returns zero if TYPE cannot be completed later due to circularity.
5413 Otherwise returns one. */
5416 can_complete_type_without_circularity (tree type)
5418 if (type == NULL_TREE || type == error_mark_node)
5420 else if (COMPLETE_TYPE_P (type))
5422 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5423 return can_complete_type_without_circularity (TREE_TYPE (type));
5424 else if (CLASS_TYPE_P (type)
5425 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5432 instantiate_class_template (tree type)
5434 tree template, args, pattern, t, member;
5439 if (type == error_mark_node)
5440 return error_mark_node;
5442 if (TYPE_BEING_DEFINED (type)
5443 || COMPLETE_TYPE_P (type)
5444 || dependent_type_p (type))
5447 /* Figure out which template is being instantiated. */
5448 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5449 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5451 /* Figure out which arguments are being used to do the
5453 args = CLASSTYPE_TI_ARGS (type);
5455 /* Determine what specialization of the original template to
5457 t = most_specialized_class (template, args);
5458 if (t == error_mark_node)
5460 const char *str = "candidates are:";
5461 error ("ambiguous class template instantiation for %q#T", type);
5462 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5465 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5467 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5471 TYPE_BEING_DEFINED (type) = 1;
5472 return error_mark_node;
5476 pattern = TREE_TYPE (t);
5478 pattern = TREE_TYPE (template);
5480 /* If the template we're instantiating is incomplete, then clearly
5481 there's nothing we can do. */
5482 if (!COMPLETE_TYPE_P (pattern))
5485 /* If we've recursively instantiated too many templates, stop. */
5486 if (! push_tinst_level (type))
5489 /* Now we're really doing the instantiation. Mark the type as in
5490 the process of being defined. */
5491 TYPE_BEING_DEFINED (type) = 1;
5493 /* We may be in the middle of deferred access check. Disable
5495 push_deferring_access_checks (dk_no_deferred);
5497 push_to_top_level ();
5501 /* This TYPE is actually an instantiation of a partial
5502 specialization. We replace the innermost set of ARGS with
5503 the arguments appropriate for substitution. For example,
5506 template <class T> struct S {};
5507 template <class T> struct S<T*> {};
5509 and supposing that we are instantiating S<int*>, ARGS will
5510 present be {int*} but we need {int}. */
5512 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5515 /* If there were multiple levels in ARGS, replacing the
5516 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5517 want, so we make a copy first. */
5518 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5520 args = copy_node (args);
5521 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5527 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5529 /* Set the input location to the template definition. This is needed
5530 if tsubsting causes an error. */
5531 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (pattern));
5533 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5534 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5535 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5536 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5537 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5538 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5539 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5540 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5541 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5542 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5543 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5544 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5545 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5546 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5547 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5548 if (ANON_AGGR_TYPE_P (pattern))
5549 SET_ANON_AGGR_TYPE_P (type);
5551 pbinfo = TYPE_BINFO (pattern);
5553 /* We should never instantiate a nested class before its enclosing
5554 class; we need to look up the nested class by name before we can
5555 instantiate it, and that lookup should instantiate the enclosing
5557 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5558 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5559 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5561 base_list = NULL_TREE;
5562 if (BINFO_N_BASE_BINFOS (pbinfo))
5565 tree context = TYPE_CONTEXT (type);
5569 /* We must enter the scope containing the type, as that is where
5570 the accessibility of types named in dependent bases are
5572 pop_p = push_scope (context ? context : global_namespace);
5574 /* Substitute into each of the bases to determine the actual
5576 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5579 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5581 /* Substitute to figure out the base class. */
5582 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5583 if (base == error_mark_node)
5586 base_list = tree_cons (access, base, base_list);
5587 if (BINFO_VIRTUAL_P (pbase_binfo))
5588 TREE_TYPE (base_list) = integer_type_node;
5591 /* The list is now in reverse order; correct that. */
5592 base_list = nreverse (base_list);
5595 pop_scope (context ? context : global_namespace);
5597 /* Now call xref_basetypes to set up all the base-class
5599 xref_basetypes (type, base_list);
5602 /* Now that our base classes are set up, enter the scope of the
5603 class, so that name lookups into base classes, etc. will work
5604 correctly. This is precisely analogous to what we do in
5605 begin_class_definition when defining an ordinary non-template
5609 /* Now members are processed in the order of declaration. */
5610 for (member = CLASSTYPE_DECL_LIST (pattern);
5611 member; member = TREE_CHAIN (member))
5613 tree t = TREE_VALUE (member);
5615 if (TREE_PURPOSE (member))
5619 /* Build new CLASSTYPE_NESTED_UTDS. */
5622 tree name = TYPE_IDENTIFIER (tag);
5624 bool class_template_p;
5626 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5627 && TYPE_LANG_SPECIFIC (tag)
5628 && CLASSTYPE_IS_TEMPLATE (tag));
5629 /* If the member is a class template, then -- even after
5630 substituition -- there may be dependent types in the
5631 template argument list for the class. We increment
5632 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5633 that function will assume that no types are dependent
5634 when outside of a template. */
5635 if (class_template_p)
5636 ++processing_template_decl;
5637 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5638 if (class_template_p)
5639 --processing_template_decl;
5640 if (newtag == error_mark_node)
5643 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5645 if (class_template_p)
5646 /* Unfortunately, lookup_template_class sets
5647 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5648 instantiation (i.e., for the type of a member
5649 template class nested within a template class.)
5650 This behavior is required for
5651 maybe_process_partial_specialization to work
5652 correctly, but is not accurate in this case;
5653 the TAG is not an instantiation of anything.
5654 (The corresponding TEMPLATE_DECL is an
5655 instantiation, but the TYPE is not.) */
5656 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5658 /* Now, we call pushtag to put this NEWTAG into the scope of
5659 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5660 pushtag calling push_template_decl. We don't have to do
5661 this for enums because it will already have been done in
5664 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5665 pushtag (name, newtag, /*globalize=*/0);
5668 else if (TREE_CODE (t) == FUNCTION_DECL
5669 || DECL_FUNCTION_TEMPLATE_P (t))
5671 /* Build new TYPE_METHODS. */
5674 if (TREE_CODE (t) == TEMPLATE_DECL)
5675 ++processing_template_decl;
5676 r = tsubst (t, args, tf_error, NULL_TREE);
5677 if (TREE_CODE (t) == TEMPLATE_DECL)
5678 --processing_template_decl;
5679 set_current_access_from_decl (r);
5680 grok_special_member_properties (r);
5681 finish_member_declaration (r);
5685 /* Build new TYPE_FIELDS. */
5687 if (TREE_CODE (t) != CONST_DECL)
5691 /* The the file and line for this declaration, to
5692 assist in error message reporting. Since we
5693 called push_tinst_level above, we don't need to
5695 input_location = DECL_SOURCE_LOCATION (t);
5697 if (TREE_CODE (t) == TEMPLATE_DECL)
5698 ++processing_template_decl;
5699 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5700 if (TREE_CODE (t) == TEMPLATE_DECL)
5701 --processing_template_decl;
5702 if (TREE_CODE (r) == VAR_DECL)
5706 if (DECL_INITIALIZED_IN_CLASS_P (r))
5707 init = tsubst_expr (DECL_INITIAL (t), args,
5708 tf_error | tf_warning, NULL_TREE);
5712 finish_static_data_member_decl
5713 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5715 if (DECL_INITIALIZED_IN_CLASS_P (r))
5716 check_static_variable_definition (r, TREE_TYPE (r));
5718 else if (TREE_CODE (r) == FIELD_DECL)
5720 /* Determine whether R has a valid type and can be
5721 completed later. If R is invalid, then it is
5722 replaced by error_mark_node so that it will not be
5723 added to TYPE_FIELDS. */
5724 tree rtype = TREE_TYPE (r);
5725 if (can_complete_type_without_circularity (rtype))
5726 complete_type (rtype);
5728 if (!COMPLETE_TYPE_P (rtype))
5730 cxx_incomplete_type_error (r, rtype);
5731 r = error_mark_node;
5735 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5736 such a thing will already have been added to the field
5737 list by tsubst_enum in finish_member_declaration in the
5738 CLASSTYPE_NESTED_UTDS case above. */
5739 if (!(TREE_CODE (r) == TYPE_DECL
5740 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5741 && DECL_ARTIFICIAL (r)))
5743 set_current_access_from_decl (r);
5744 finish_member_declaration (r);
5751 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5753 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5755 tree friend_type = t;
5756 bool adjust_processing_template_decl = false;
5758 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5760 friend_type = tsubst_friend_class (friend_type, args);
5761 adjust_processing_template_decl = true;
5763 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5765 friend_type = tsubst (friend_type, args,
5766 tf_error | tf_warning, NULL_TREE);
5767 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5768 friend_type = TREE_TYPE (friend_type);
5769 adjust_processing_template_decl = true;
5771 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5773 friend_type = tsubst (friend_type, args,
5774 tf_error | tf_warning, NULL_TREE);
5775 /* Bump processing_template_decl for correct
5776 dependent_type_p calculation. */
5777 ++processing_template_decl;
5778 if (dependent_type_p (friend_type))
5779 adjust_processing_template_decl = true;
5780 --processing_template_decl;
5782 else if (uses_template_parms (friend_type))
5783 friend_type = tsubst (friend_type, args,
5784 tf_error | tf_warning, NULL_TREE);
5785 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5786 friend_type = friend_type;
5789 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5791 /* The call to xref_tag_from_type does injection for friend
5793 push_nested_namespace (ns);
5795 xref_tag_from_type (friend_type, NULL_TREE, 1);
5796 pop_nested_namespace (ns);
5799 if (adjust_processing_template_decl)
5800 /* Trick make_friend_class into realizing that the friend
5801 we're adding is a template, not an ordinary class. It's
5802 important that we use make_friend_class since it will
5803 perform some error-checking and output cross-reference
5805 ++processing_template_decl;
5807 if (friend_type != error_mark_node)
5808 make_friend_class (type, friend_type, /*complain=*/false);
5810 if (adjust_processing_template_decl)
5811 --processing_template_decl;
5815 /* Build new DECL_FRIENDLIST. */
5818 if (TREE_CODE (t) == TEMPLATE_DECL)
5820 ++processing_template_decl;
5821 push_deferring_access_checks (dk_no_check);
5824 r = tsubst_friend_function (t, args);
5825 add_friend (type, r, /*complain=*/false);
5826 if (TREE_CODE (t) == TEMPLATE_DECL)
5828 pop_deferring_access_checks ();
5829 --processing_template_decl;
5835 /* Set the file and line number information to whatever is given for
5836 the class itself. This puts error messages involving generated
5837 implicit functions at a predictable point, and the same point
5838 that would be used for non-template classes. */
5839 typedecl = TYPE_MAIN_DECL (type);
5840 input_location = DECL_SOURCE_LOCATION (typedecl);
5842 unreverse_member_declarations (type);
5843 finish_struct_1 (type);
5844 TYPE_BEING_DEFINED (type) = 0;
5846 /* Now that the class is complete, instantiate default arguments for
5847 any member functions. We don't do this earlier because the
5848 default arguments may reference members of the class. */
5849 if (!PRIMARY_TEMPLATE_P (template))
5850 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5851 if (TREE_CODE (t) == FUNCTION_DECL
5852 /* Implicitly generated member functions will not have template
5853 information; they are not instantiations, but instead are
5854 created "fresh" for each instantiation. */
5855 && DECL_TEMPLATE_INFO (t))
5856 tsubst_default_arguments (t);
5859 pop_from_top_level ();
5860 pop_deferring_access_checks ();
5863 /* The vtable for a template class can be emitted in any translation
5864 unit in which the class is instantiated. When there is no key
5865 method, however, finish_struct_1 will already have added TYPE to
5866 the keyed_classes list. */
5867 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5868 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5874 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5880 else if (TYPE_P (t))
5881 r = tsubst (t, args, complain, in_decl);
5884 r = tsubst_expr (t, args, complain, in_decl);
5886 if (!uses_template_parms (r))
5888 /* Sometimes, one of the args was an expression involving a
5889 template constant parameter, like N - 1. Now that we've
5890 tsubst'd, we might have something like 2 - 1. This will
5891 confuse lookup_template_class, so we do constant folding
5892 here. We have to unset processing_template_decl, to fool
5893 tsubst_copy_and_build() into building an actual tree. */
5895 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5896 as simple as it's going to get, and trying to reprocess
5897 the trees will break. Once tsubst_expr et al DTRT for
5898 non-dependent exprs, this code can go away, as the type
5899 will always be set. */
5902 int saved_processing_template_decl = processing_template_decl;
5903 processing_template_decl = 0;
5904 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5905 tf_error, /*in_decl=*/NULL_TREE,
5906 /*function_p=*/false);
5907 processing_template_decl = saved_processing_template_decl;
5915 /* Substitute ARGS into the vector or list of template arguments T. */
5918 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5920 int len = TREE_VEC_LENGTH (t);
5921 int need_new = 0, i;
5922 tree *elts = alloca (len * sizeof (tree));
5924 for (i = 0; i < len; i++)
5926 tree orig_arg = TREE_VEC_ELT (t, i);
5929 if (TREE_CODE (orig_arg) == TREE_VEC)
5930 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5932 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5934 if (new_arg == error_mark_node)
5935 return error_mark_node;
5938 if (new_arg != orig_arg)
5945 t = make_tree_vec (len);
5946 for (i = 0; i < len; i++)
5947 TREE_VEC_ELT (t, i) = elts[i];
5952 /* Return the result of substituting ARGS into the template parameters
5953 given by PARMS. If there are m levels of ARGS and m + n levels of
5954 PARMS, then the result will contain n levels of PARMS. For
5955 example, if PARMS is `template <class T> template <class U>
5956 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5957 result will be `template <int*, double, class V>'. */
5960 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5965 for (new_parms = &r;
5966 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5967 new_parms = &(TREE_CHAIN (*new_parms)),
5968 parms = TREE_CHAIN (parms))
5971 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5974 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5976 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5977 tree default_value = TREE_PURPOSE (tuple);
5978 tree parm_decl = TREE_VALUE (tuple);
5980 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5981 default_value = tsubst_template_arg (default_value, args,
5982 complain, NULL_TREE);
5984 tuple = build_tree_list (default_value, parm_decl);
5985 TREE_VEC_ELT (new_vec, i) = tuple;
5989 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
5990 - TMPL_ARGS_DEPTH (args)),
5991 new_vec, NULL_TREE);
5997 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5998 type T. If T is not an aggregate or enumeration type, it is
5999 handled as if by tsubst. IN_DECL is as for tsubst. If
6000 ENTERING_SCOPE is nonzero, T is the context for a template which
6001 we are presently tsubst'ing. Return the substituted value. */
6004 tsubst_aggr_type (tree t,
6006 tsubst_flags_t complain,
6013 switch (TREE_CODE (t))
6016 if (TYPE_PTRMEMFUNC_P (t))
6017 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6019 /* Else fall through. */
6022 if (TYPE_TEMPLATE_INFO (t))
6028 /* First, determine the context for the type we are looking
6030 context = TYPE_CONTEXT (t);
6032 context = tsubst_aggr_type (context, args, complain,
6033 in_decl, /*entering_scope=*/1);
6035 /* Then, figure out what arguments are appropriate for the
6036 type we are trying to find. For example, given:
6038 template <class T> struct S;
6039 template <class T, class U> void f(T, U) { S<U> su; }
6041 and supposing that we are instantiating f<int, double>,
6042 then our ARGS will be {int, double}, but, when looking up
6043 S we only want {double}. */
6044 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6046 if (argvec == error_mark_node)
6047 return error_mark_node;
6049 r = lookup_template_class (t, argvec, in_decl, context,
6050 entering_scope, complain);
6052 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6055 /* This is not a template type, so there's nothing to do. */
6059 return tsubst (t, args, complain, in_decl);
6063 /* Substitute into the default argument ARG (a default argument for
6064 FN), which has the indicated TYPE. */
6067 tsubst_default_argument (tree fn, tree type, tree arg)
6069 tree saved_class_ptr = NULL_TREE;
6070 tree saved_class_ref = NULL_TREE;
6072 /* This default argument came from a template. Instantiate the
6073 default argument here, not in tsubst. In the case of
6082 we must be careful to do name lookup in the scope of S<T>,
6083 rather than in the current class. */
6084 push_access_scope (fn);
6085 /* The default argument expression should not be considered to be
6086 within the scope of FN. Since push_access_scope sets
6087 current_function_decl, we must explicitly clear it here. */
6088 current_function_decl = NULL_TREE;
6089 /* The "this" pointer is not valid in a default argument. */
6092 saved_class_ptr = current_class_ptr;
6093 cp_function_chain->x_current_class_ptr = NULL_TREE;
6094 saved_class_ref = current_class_ref;
6095 cp_function_chain->x_current_class_ref = NULL_TREE;
6098 push_deferring_access_checks(dk_no_deferred);
6099 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6100 tf_error | tf_warning, NULL_TREE);
6101 pop_deferring_access_checks();
6103 /* Restore the "this" pointer. */
6106 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6107 cp_function_chain->x_current_class_ref = saved_class_ref;
6110 pop_access_scope (fn);
6112 /* Make sure the default argument is reasonable. */
6113 arg = check_default_argument (type, arg);
6118 /* Substitute into all the default arguments for FN. */
6121 tsubst_default_arguments (tree fn)
6126 tmpl_args = DECL_TI_ARGS (fn);
6128 /* If this function is not yet instantiated, we certainly don't need
6129 its default arguments. */
6130 if (uses_template_parms (tmpl_args))
6133 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6135 arg = TREE_CHAIN (arg))
6136 if (TREE_PURPOSE (arg))
6137 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6139 TREE_PURPOSE (arg));
6142 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
6143 (already computed) substitution of ARGS into TREE_TYPE (T), if
6144 appropriate. Return the result of the substitution. Issue error
6145 and warning messages under control of COMPLAIN. */
6148 tsubst_decl (tree t, tree args, tree type, tsubst_flags_t complain)
6150 location_t saved_loc;
6154 /* Set the filename and linenumber to improve error-reporting. */
6155 saved_loc = input_location;
6156 input_location = DECL_SOURCE_LOCATION (t);
6158 switch (TREE_CODE (t))
6162 /* We can get here when processing a member template function
6163 of a template class. */
6164 tree decl = DECL_TEMPLATE_RESULT (t);
6166 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
6168 if (!is_template_template_parm)
6170 /* We might already have an instance of this template.
6171 The ARGS are for the surrounding class type, so the
6172 full args contain the tsubst'd args for the context,
6173 plus the innermost args from the template decl. */
6174 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6175 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6176 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6179 full_args = tsubst_template_args (tmpl_args, args,
6182 /* tsubst_template_args doesn't copy the vector if
6183 nothing changed. But, *something* should have
6185 gcc_assert (full_args != tmpl_args);
6187 spec = retrieve_specialization (t, full_args,
6188 /*class_specializations_p=*/true);
6189 if (spec != NULL_TREE)
6196 /* Make a new template decl. It will be similar to the
6197 original, but will record the current template arguments.
6198 We also create a new function declaration, which is just
6199 like the old one, but points to this new template, rather
6200 than the old one. */
6202 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6203 TREE_CHAIN (r) = NULL_TREE;
6205 if (is_template_template_parm)
6207 tree new_decl = tsubst (decl, args, complain, in_decl);
6208 DECL_TEMPLATE_RESULT (r) = new_decl;
6209 TREE_TYPE (r) = TREE_TYPE (new_decl);
6214 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6216 /*entering_scope=*/1);
6217 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6219 if (TREE_CODE (decl) == TYPE_DECL)
6221 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6222 if (new_type == error_mark_node)
6223 return error_mark_node;
6225 TREE_TYPE (r) = new_type;
6226 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6227 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6228 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6232 tree new_decl = tsubst (decl, args, complain, in_decl);
6233 if (new_decl == error_mark_node)
6234 return error_mark_node;
6236 DECL_TEMPLATE_RESULT (r) = new_decl;
6237 DECL_TI_TEMPLATE (new_decl) = r;
6238 TREE_TYPE (r) = TREE_TYPE (new_decl);
6239 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6242 SET_DECL_IMPLICIT_INSTANTIATION (r);
6243 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6244 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6246 /* The template parameters for this new template are all the
6247 template parameters for the old template, except the
6248 outermost level of parameters. */
6249 DECL_TEMPLATE_PARMS (r)
6250 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6253 if (PRIMARY_TEMPLATE_P (t))
6254 DECL_PRIMARY_TEMPLATE (r) = r;
6256 if (TREE_CODE (decl) != TYPE_DECL)
6257 /* Record this non-type partial instantiation. */
6258 register_specialization (r, t,
6259 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6266 tree argvec = NULL_TREE;
6273 /* Nobody should be tsubst'ing into non-template functions. */
6274 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6276 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6281 /* If T is not dependent, just return it. We have to
6282 increment PROCESSING_TEMPLATE_DECL because
6283 value_dependent_expression_p assumes that nothing is
6284 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6285 ++processing_template_decl;
6286 dependent_p = value_dependent_expression_p (t);
6287 --processing_template_decl;
6291 /* Calculate the most general template of which R is a
6292 specialization, and the complete set of arguments used to
6294 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6295 argvec = tsubst_template_args (DECL_TI_ARGS
6296 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6297 args, complain, in_decl);
6299 /* Check to see if we already have this specialization. */
6300 spec = retrieve_specialization (gen_tmpl, argvec,
6301 /*class_specializations_p=*/false);
6309 /* We can see more levels of arguments than parameters if
6310 there was a specialization of a member template, like
6313 template <class T> struct S { template <class U> void f(); }
6314 template <> template <class U> void S<int>::f(U);
6316 Here, we'll be substituting into the specialization,
6317 because that's where we can find the code we actually
6318 want to generate, but we'll have enough arguments for
6319 the most general template.
6321 We also deal with the peculiar case:
6323 template <class T> struct S {
6324 template <class U> friend void f();
6326 template <class U> void f() {}
6328 template void f<double>();
6330 Here, the ARGS for the instantiation of will be {int,
6331 double}. But, we only need as many ARGS as there are
6332 levels of template parameters in CODE_PATTERN. We are
6333 careful not to get fooled into reducing the ARGS in
6336 template <class T> struct S { template <class U> void f(U); }
6337 template <class T> template <> void S<T>::f(int) {}
6339 which we can spot because the pattern will be a
6340 specialization in this case. */
6341 args_depth = TMPL_ARGS_DEPTH (args);
6343 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6344 if (args_depth > parms_depth
6345 && !DECL_TEMPLATE_SPECIALIZATION (t))
6346 args = get_innermost_template_args (args, parms_depth);
6350 /* This special case arises when we have something like this:
6352 template <class T> struct S {
6353 friend void f<int>(int, double);
6356 Here, the DECL_TI_TEMPLATE for the friend declaration
6357 will be an IDENTIFIER_NODE. We are being called from
6358 tsubst_friend_function, and we want only to create a
6359 new decl (R) with appropriate types so that we can call
6360 determine_specialization. */
6361 gen_tmpl = NULL_TREE;
6364 if (DECL_CLASS_SCOPE_P (t))
6366 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6370 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6371 complain, t, /*entering_scope=*/1);
6376 ctx = DECL_CONTEXT (t);
6378 type = tsubst (type, args, complain, in_decl);
6379 if (type == error_mark_node)
6380 return error_mark_node;
6382 /* We do NOT check for matching decls pushed separately at this
6383 point, as they may not represent instantiations of this
6384 template, and in any case are considered separate under the
6387 DECL_USE_TEMPLATE (r) = 0;
6388 TREE_TYPE (r) = type;
6389 /* Clear out the mangled name and RTL for the instantiation. */
6390 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6391 SET_DECL_RTL (r, NULL_RTX);
6392 DECL_INITIAL (r) = NULL_TREE;
6393 DECL_CONTEXT (r) = ctx;
6395 if (member && DECL_CONV_FN_P (r))
6396 /* Type-conversion operator. Reconstruct the name, in
6397 case it's the name of one of the template's parameters. */
6398 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6400 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6402 DECL_RESULT (r) = NULL_TREE;
6404 TREE_STATIC (r) = 0;
6405 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6406 DECL_EXTERNAL (r) = 1;
6407 /* If this is an instantiation of a function with internal
6408 linkage, we already know what object file linkage will be
6409 assigned to the instantiation. */
6410 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6411 DECL_DEFER_OUTPUT (r) = 0;
6412 TREE_CHAIN (r) = NULL_TREE;
6413 DECL_PENDING_INLINE_INFO (r) = 0;
6414 DECL_PENDING_INLINE_P (r) = 0;
6415 DECL_SAVED_TREE (r) = NULL_TREE;
6417 if (DECL_CLONED_FUNCTION (r))
6419 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6421 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6422 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6425 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6426 this in the special friend case mentioned above where
6427 GEN_TMPL is NULL. */
6430 DECL_TEMPLATE_INFO (r)
6431 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6432 SET_DECL_IMPLICIT_INSTANTIATION (r);
6433 register_specialization (r, gen_tmpl, argvec);
6435 /* We're not supposed to instantiate default arguments
6436 until they are called, for a template. But, for a
6439 template <class T> void f ()
6440 { extern void g(int i = T()); }
6442 we should do the substitution when the template is
6443 instantiated. We handle the member function case in
6444 instantiate_class_template since the default arguments
6445 might refer to other members of the class. */
6447 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6448 && !uses_template_parms (argvec))
6449 tsubst_default_arguments (r);
6452 /* Copy the list of befriending classes. */
6453 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6455 friends = &TREE_CHAIN (*friends))
6457 *friends = copy_node (*friends);
6458 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6463 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6465 maybe_retrofit_in_chrg (r);
6466 if (DECL_CONSTRUCTOR_P (r))
6467 grok_ctor_properties (ctx, r);
6468 /* If this is an instantiation of a member template, clone it.
6469 If it isn't, that'll be handled by
6470 clone_constructors_and_destructors. */
6471 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6472 clone_function_decl (r, /*update_method_vec_p=*/0);
6474 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6475 grok_op_properties (r, DECL_FRIEND_P (r),
6476 (complain & tf_error) != 0);
6478 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6479 SET_DECL_FRIEND_CONTEXT (r,
6480 tsubst (DECL_FRIEND_CONTEXT (t),
6481 args, complain, in_decl));
6488 if (DECL_TEMPLATE_PARM_P (t))
6489 SET_DECL_TEMPLATE_PARM_P (r);
6491 TREE_TYPE (r) = type;
6492 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6494 if (DECL_INITIAL (r))
6496 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6497 DECL_INITIAL (r) = TREE_TYPE (r);
6499 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6503 DECL_CONTEXT (r) = NULL_TREE;
6505 if (!DECL_TEMPLATE_PARM_P (r))
6506 DECL_ARG_TYPE (r) = type_passed_as (type);
6508 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6509 complain, TREE_CHAIN (t));
6516 TREE_TYPE (r) = type;
6517 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6519 /* We don't have to set DECL_CONTEXT here; it is set by
6520 finish_member_declaration. */
6521 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6523 TREE_CHAIN (r) = NULL_TREE;
6524 if (VOID_TYPE_P (type))
6525 cp_error_at ("instantiation of %qD as type %qT", r, type);
6532 /* It is not a dependent using decl any more. */
6533 TREE_TYPE (r) = void_type_node;
6535 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6537 = tsubst_copy (DECL_NAME (t), args, complain, in_decl);
6538 TREE_CHAIN (r) = NULL_TREE;
6543 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6544 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6546 /* If this is the canonical decl, we don't have to mess with
6547 instantiations, and often we can't (for typename, template
6548 type parms and such). Note that TYPE_NAME is not correct for
6549 the above test if we've copied the type for a typedef. */
6550 r = TYPE_NAME (type);
6558 tree argvec = NULL_TREE;
6559 tree gen_tmpl = NULL_TREE;
6561 tree tmpl = NULL_TREE;
6565 /* Assume this is a non-local variable. */
6568 if (TYPE_P (CP_DECL_CONTEXT (t)))
6569 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6571 in_decl, /*entering_scope=*/1);
6572 else if (DECL_NAMESPACE_SCOPE_P (t))
6573 ctx = DECL_CONTEXT (t);
6576 /* Subsequent calls to pushdecl will fill this in. */
6581 /* Check to see if we already have this specialization. */
6584 tmpl = DECL_TI_TEMPLATE (t);
6585 gen_tmpl = most_general_template (tmpl);
6586 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6587 spec = retrieve_specialization (gen_tmpl, argvec,
6588 /*class_specializations_p=*/false);
6591 spec = retrieve_local_specialization (t);
6600 if (TREE_CODE (r) == VAR_DECL)
6602 type = complete_type (type);
6603 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6604 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6605 type = check_var_type (DECL_NAME (r), type);
6607 else if (DECL_SELF_REFERENCE_P (t))
6608 SET_DECL_SELF_REFERENCE_P (r);
6609 TREE_TYPE (r) = type;
6610 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6611 DECL_CONTEXT (r) = ctx;
6612 /* Clear out the mangled name and RTL for the instantiation. */
6613 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6614 SET_DECL_RTL (r, NULL_RTX);
6616 /* Don't try to expand the initializer until someone tries to use
6617 this variable; otherwise we run into circular dependencies. */
6618 DECL_INITIAL (r) = NULL_TREE;
6619 SET_DECL_RTL (r, NULL_RTX);
6620 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6622 /* Even if the original location is out of scope, the newly
6623 substituted one is not. */
6624 if (TREE_CODE (r) == VAR_DECL)
6626 DECL_DEAD_FOR_LOCAL (r) = 0;
6627 DECL_INITIALIZED_P (r) = 0;
6632 /* A static data member declaration is always marked
6633 external when it is declared in-class, even if an
6634 initializer is present. We mimic the non-template
6636 DECL_EXTERNAL (r) = 1;
6638 register_specialization (r, gen_tmpl, argvec);
6639 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6640 SET_DECL_IMPLICIT_INSTANTIATION (r);
6643 register_local_specialization (r, t);
6645 TREE_CHAIN (r) = NULL_TREE;
6654 /* Restore the file and line information. */
6655 input_location = saved_loc;
6660 /* Substitute into the ARG_TYPES of a function type. */
6663 tsubst_arg_types (tree arg_types,
6665 tsubst_flags_t complain,
6668 tree remaining_arg_types;
6671 if (!arg_types || arg_types == void_list_node)
6674 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6675 args, complain, in_decl);
6676 if (remaining_arg_types == error_mark_node)
6677 return error_mark_node;
6679 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6680 if (type == error_mark_node)
6681 return error_mark_node;
6682 if (VOID_TYPE_P (type))
6684 if (complain & tf_error)
6686 error ("invalid parameter type %qT", type);
6688 cp_error_at ("in declaration %qD", in_decl);
6690 return error_mark_node;
6693 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6694 top-level qualifiers as required. */
6695 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6697 /* Note that we do not substitute into default arguments here. The
6698 standard mandates that they be instantiated only when needed,
6699 which is done in build_over_call. */
6700 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6701 remaining_arg_types);
6705 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6706 *not* handle the exception-specification for FNTYPE, because the
6707 initial substitution of explicitly provided template parameters
6708 during argument deduction forbids substitution into the
6709 exception-specification:
6713 All references in the function type of the function template to the
6714 corresponding template parameters are replaced by the specified tem-
6715 plate argument values. If a substitution in a template parameter or
6716 in the function type of the function template results in an invalid
6717 type, type deduction fails. [Note: The equivalent substitution in
6718 exception specifications is done only when the function is instanti-
6719 ated, at which point a program is ill-formed if the substitution
6720 results in an invalid type.] */
6723 tsubst_function_type (tree t,
6725 tsubst_flags_t complain,
6732 /* The TYPE_CONTEXT is not used for function/method types. */
6733 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6735 /* Substitute the return type. */
6736 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6737 if (return_type == error_mark_node)
6738 return error_mark_node;
6740 /* Substitute the argument types. */
6741 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6743 if (arg_types == error_mark_node)
6744 return error_mark_node;
6746 /* Construct a new type node and return it. */
6747 if (TREE_CODE (t) == FUNCTION_TYPE)
6748 fntype = build_function_type (return_type, arg_types);
6751 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6752 if (! IS_AGGR_TYPE (r))
6756 Type deduction may fail for any of the following
6759 -- Attempting to create "pointer to member of T" when T
6760 is not a class type. */
6761 if (complain & tf_error)
6762 error ("creating pointer to member function of non-class type %qT",
6764 return error_mark_node;
6767 fntype = build_method_type_directly (r, return_type,
6768 TREE_CHAIN (arg_types));
6770 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6771 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6776 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6777 ARGS into that specification, and return the substituted
6778 specification. If there is no specification, return NULL_TREE. */
6781 tsubst_exception_specification (tree fntype,
6783 tsubst_flags_t complain,
6789 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6790 new_specs = NULL_TREE;
6793 if (! TREE_VALUE (specs))
6799 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6800 if (spec == error_mark_node)
6802 new_specs = add_exception_specifier (new_specs, spec, complain);
6803 specs = TREE_CHAIN (specs);
6809 /* Substitute into the PARMS of a call-declarator. */
6812 tsubst_call_declarator_parms (tree parms,
6814 tsubst_flags_t complain,
6821 if (!parms || parms == void_list_node)
6824 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6825 args, complain, in_decl);
6827 /* Figure out the type of this parameter. */
6828 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6830 /* Figure out the default argument as well. Note that we use
6831 tsubst_expr since the default argument is really an expression. */
6832 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6834 /* Chain this parameter on to the front of those we have already
6835 processed. We don't use hash_tree_cons because that function
6836 doesn't check TREE_PARMLIST. */
6837 new_parms = tree_cons (defarg, type, new_parms);
6842 /* Take the tree structure T and replace template parameters used
6843 therein with the argument vector ARGS. IN_DECL is an associated
6844 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6845 Issue error and warning messages under control of COMPLAIN. Note
6846 that we must be relatively non-tolerant of extensions here, in
6847 order to preserve conformance; if we allow substitutions that
6848 should not be allowed, we may allow argument deductions that should
6849 not succeed, and therefore report ambiguous overload situations
6850 where there are none. In theory, we could allow the substitution,
6851 but indicate that it should have failed, and allow our caller to
6852 make sure that the right thing happens, but we don't try to do this
6855 This function is used for dealing with types, decls and the like;
6856 for expressions, use tsubst_expr or tsubst_copy. */
6859 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6863 if (t == NULL_TREE || t == error_mark_node
6864 || t == integer_type_node
6865 || t == void_type_node
6866 || t == char_type_node
6867 || t == unknown_type_node
6868 || TREE_CODE (t) == NAMESPACE_DECL)
6871 if (TREE_CODE (t) == IDENTIFIER_NODE)
6872 type = IDENTIFIER_TYPE_VALUE (t);
6874 type = TREE_TYPE (t);
6876 gcc_assert (type != unknown_type_node);
6878 if (type && TREE_CODE (t) != FUNCTION_DECL
6879 && TREE_CODE (t) != TYPENAME_TYPE
6880 && TREE_CODE (t) != TEMPLATE_DECL
6881 && TREE_CODE (t) != IDENTIFIER_NODE
6882 && TREE_CODE (t) != FUNCTION_TYPE
6883 && TREE_CODE (t) != METHOD_TYPE)
6884 type = tsubst (type, args, complain, in_decl);
6885 if (type == error_mark_node)
6886 return error_mark_node;
6889 return tsubst_decl (t, args, type, complain);
6891 switch (TREE_CODE (t))
6896 return tsubst_aggr_type (t, args, complain, in_decl,
6897 /*entering_scope=*/0);
6900 case IDENTIFIER_NODE:
6912 if (t == integer_type_node)
6915 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6916 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6920 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6922 /* The array dimension behaves like a non-type template arg,
6923 in that we want to fold it as much as possible. */
6924 max = tsubst_template_arg (omax, args, complain, in_decl);
6925 if (!processing_template_decl)
6926 max = decl_constant_value (max);
6928 if (integer_zerop (omax))
6930 /* Still allow an explicit array of size zero. */
6932 pedwarn ("creating array with size zero");
6934 else if (integer_zerop (max)
6935 || (TREE_CODE (max) == INTEGER_CST
6936 && INT_CST_LT (max, integer_zero_node)))
6940 Type deduction may fail for any of the following
6943 Attempting to create an array with a size that is
6944 zero or negative. */
6945 if (complain & tf_error)
6946 error ("creating array with size zero (%qE)", max);
6948 return error_mark_node;
6951 return compute_array_index_type (NULL_TREE, max);
6954 case TEMPLATE_TYPE_PARM:
6955 case TEMPLATE_TEMPLATE_PARM:
6956 case BOUND_TEMPLATE_TEMPLATE_PARM:
6957 case TEMPLATE_PARM_INDEX:
6962 tree arg = NULL_TREE;
6966 gcc_assert (TREE_VEC_LENGTH (args) > 0);
6967 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6968 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6969 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6971 idx = TEMPLATE_TYPE_IDX (t);
6972 level = TEMPLATE_TYPE_LEVEL (t);
6976 idx = TEMPLATE_PARM_IDX (t);
6977 level = TEMPLATE_PARM_LEVEL (t);
6980 levels = TMPL_ARGS_DEPTH (args);
6981 if (level <= levels)
6982 arg = TMPL_ARG (args, level, idx);
6984 if (arg == error_mark_node)
6985 return error_mark_node;
6986 else if (arg != NULL_TREE)
6988 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6990 gcc_assert (TYPE_P (arg));
6991 return cp_build_qualified_type_real
6992 (arg, cp_type_quals (arg) | cp_type_quals (t),
6993 complain | tf_ignore_bad_quals);
6995 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6997 /* We are processing a type constructed from a
6998 template template parameter. */
6999 tree argvec = tsubst (TYPE_TI_ARGS (t),
7000 args, complain, in_decl);
7001 if (argvec == error_mark_node)
7002 return error_mark_node;
7004 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7005 are resolving nested-types in the signature of a
7006 member function templates. Otherwise ARG is a
7007 TEMPLATE_DECL and is the real template to be
7009 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7010 arg = TYPE_NAME (arg);
7012 r = lookup_template_class (arg,
7015 /*entering_scope=*/0,
7017 return cp_build_qualified_type_real
7018 (r, TYPE_QUALS (t), complain);
7021 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7026 /* This can happen during the attempted tsubst'ing in
7027 unify. This means that we don't yet have any information
7028 about the template parameter in question. */
7031 /* If we get here, we must have been looking at a parm for a
7032 more deeply nested template. Make a new version of this
7033 template parameter, but with a lower level. */
7034 switch (TREE_CODE (t))
7036 case TEMPLATE_TYPE_PARM:
7037 case TEMPLATE_TEMPLATE_PARM:
7038 case BOUND_TEMPLATE_TEMPLATE_PARM:
7039 if (cp_type_quals (t))
7041 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7042 r = cp_build_qualified_type_real
7043 (r, cp_type_quals (t),
7044 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7045 ? tf_ignore_bad_quals : 0));
7050 TEMPLATE_TYPE_PARM_INDEX (r)
7051 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7053 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7054 TYPE_MAIN_VARIANT (r) = r;
7055 TYPE_POINTER_TO (r) = NULL_TREE;
7056 TYPE_REFERENCE_TO (r) = NULL_TREE;
7058 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7060 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7062 if (argvec == error_mark_node)
7063 return error_mark_node;
7065 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7066 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7071 case TEMPLATE_PARM_INDEX:
7072 r = reduce_template_parm_level (t, type, levels);
7084 tree purpose, value, chain;
7086 if (t == void_list_node)
7089 purpose = TREE_PURPOSE (t);
7092 purpose = tsubst (purpose, args, complain, in_decl);
7093 if (purpose == error_mark_node)
7094 return error_mark_node;
7096 value = TREE_VALUE (t);
7099 value = tsubst (value, args, complain, in_decl);
7100 if (value == error_mark_node)
7101 return error_mark_node;
7103 chain = TREE_CHAIN (t);
7104 if (chain && chain != void_type_node)
7106 chain = tsubst (chain, args, complain, in_decl);
7107 if (chain == error_mark_node)
7108 return error_mark_node;
7110 if (purpose == TREE_PURPOSE (t)
7111 && value == TREE_VALUE (t)
7112 && chain == TREE_CHAIN (t))
7114 return hash_tree_cons (purpose, value, chain);
7118 /* We should never be tsubsting a binfo. */
7122 /* A vector of template arguments. */
7124 return tsubst_template_args (t, args, complain, in_decl);
7127 case REFERENCE_TYPE:
7129 enum tree_code code;
7131 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7134 code = TREE_CODE (t);
7139 Type deduction may fail for any of the following
7142 -- Attempting to create a pointer to reference type.
7143 -- Attempting to create a reference to a reference type or
7144 a reference to void. */
7145 if (TREE_CODE (type) == REFERENCE_TYPE
7146 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7148 static location_t last_loc;
7150 /* We keep track of the last time we issued this error
7151 message to avoid spewing a ton of messages during a
7152 single bad template instantiation. */
7153 if (complain & tf_error
7154 #ifdef USE_MAPPED_LOCATION
7155 && last_loc != input_location
7157 && (last_loc.line != input_line
7158 || last_loc.file != input_filename)
7162 if (TREE_CODE (type) == VOID_TYPE)
7163 error ("forming reference to void");
7165 error ("forming %s to reference type %qT",
7166 (code == POINTER_TYPE) ? "pointer" : "reference",
7168 last_loc = input_location;
7171 return error_mark_node;
7173 else if (code == POINTER_TYPE)
7175 r = build_pointer_type (type);
7176 if (TREE_CODE (type) == METHOD_TYPE)
7177 r = build_ptrmemfunc_type (r);
7180 r = build_reference_type (type);
7181 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7183 if (r != error_mark_node)
7184 /* Will this ever be needed for TYPE_..._TO values? */
7191 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7192 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7196 Type deduction may fail for any of the following
7199 -- Attempting to create "pointer to member of T" when T
7200 is not a class type. */
7201 if (complain & tf_error)
7202 error ("creating pointer to member of non-class type %qT", r);
7203 return error_mark_node;
7205 if (TREE_CODE (type) == REFERENCE_TYPE)
7207 if (complain & tf_error)
7208 error ("creating pointer to member reference type %qT", type);
7210 return error_mark_node;
7212 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7213 if (TREE_CODE (type) == FUNCTION_TYPE)
7215 /* This is really a method type. The cv qualifiers of the
7216 this pointer should _not_ be determined by the cv
7217 qualifiers of the class type. They should be held
7218 somewhere in the FUNCTION_TYPE, but we don't do that at
7219 the moment. Consider
7220 typedef void (Func) () const;
7222 template <typename T1> void Foo (Func T1::*);
7227 method_type = build_method_type_directly (TYPE_MAIN_VARIANT (r),
7229 TYPE_ARG_TYPES (type));
7230 return build_ptrmemfunc_type (build_pointer_type (method_type));
7233 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7242 fntype = tsubst_function_type (t, args, complain, in_decl);
7243 if (fntype == error_mark_node)
7244 return error_mark_node;
7246 /* Substitute the exception specification. */
7247 specs = tsubst_exception_specification (t, args, complain,
7250 fntype = build_exception_variant (fntype, specs);
7255 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7256 if (domain == error_mark_node)
7257 return error_mark_node;
7259 /* As an optimization, we avoid regenerating the array type if
7260 it will obviously be the same as T. */
7261 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7264 /* These checks should match the ones in grokdeclarator.
7268 The deduction may fail for any of the following reasons:
7270 -- Attempting to create an array with an element type that
7271 is void, a function type, or a reference type, or [DR337]
7272 an abstract class type. */
7273 if (TREE_CODE (type) == VOID_TYPE
7274 || TREE_CODE (type) == FUNCTION_TYPE
7275 || TREE_CODE (type) == REFERENCE_TYPE)
7277 if (complain & tf_error)
7278 error ("creating array of %qT", type);
7279 return error_mark_node;
7281 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7283 if (complain & tf_error)
7284 error ("creating array of %qT, which is an abstract class type",
7286 return error_mark_node;
7289 r = build_cplus_array_type (type, domain);
7296 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7297 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7299 if (e1 == error_mark_node || e2 == error_mark_node)
7300 return error_mark_node;
7302 return fold (build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2));
7308 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7309 if (e == error_mark_node)
7310 return error_mark_node;
7312 return fold (build1 (TREE_CODE (t), TREE_TYPE (t), e));
7317 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7318 in_decl, /*entering_scope=*/1);
7319 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7322 if (ctx == error_mark_node || f == error_mark_node)
7323 return error_mark_node;
7325 if (!IS_AGGR_TYPE (ctx))
7327 if (complain & tf_error)
7328 error ("%qT is not a class, struct, or union type", ctx);
7329 return error_mark_node;
7331 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7333 /* Normally, make_typename_type does not require that the CTX
7334 have complete type in order to allow things like:
7336 template <class T> struct S { typename S<T>::X Y; };
7338 But, such constructs have already been resolved by this
7339 point, so here CTX really should have complete type, unless
7340 it's a partial instantiation. */
7341 ctx = complete_type (ctx);
7342 if (!COMPLETE_TYPE_P (ctx))
7344 if (complain & tf_error)
7345 cxx_incomplete_type_error (NULL_TREE, ctx);
7346 return error_mark_node;
7350 f = make_typename_type (ctx, f,
7351 (complain & tf_error) | tf_keep_type_decl);
7352 if (f == error_mark_node)
7354 if (TREE_CODE (f) == TYPE_DECL)
7356 complain |= tf_ignore_bad_quals;
7360 return cp_build_qualified_type_real
7361 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7364 case UNBOUND_CLASS_TEMPLATE:
7366 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7367 in_decl, /*entering_scope=*/1);
7368 tree name = TYPE_IDENTIFIER (t);
7369 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7371 if (ctx == error_mark_node || name == error_mark_node)
7372 return error_mark_node;
7375 parm_list = tsubst_template_parms (parm_list, args, complain);
7376 return make_unbound_class_template (ctx, name, parm_list, complain);
7386 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7387 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7388 if (e1 == error_mark_node || e2 == error_mark_node)
7389 return error_mark_node;
7391 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7396 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7397 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7398 if (e1 == error_mark_node || e2 == error_mark_node)
7399 return error_mark_node;
7401 return build_nt (TREE_CODE (t), e1, e2);
7408 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7409 complain, in_decl));
7410 return cp_build_qualified_type_real (type,
7412 | cp_type_quals (type),
7417 sorry ("use of `%s' in template",
7418 tree_code_name [(int) TREE_CODE (t)]);
7419 return error_mark_node;
7423 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7424 type of the expression on the left-hand side of the "." or "->"
7428 tsubst_baselink (tree baselink, tree object_type,
7429 tree args, tsubst_flags_t complain, tree in_decl)
7432 tree qualifying_scope;
7434 tree template_args = 0;
7435 bool template_id_p = false;
7437 /* A baselink indicates a function from a base class. The
7438 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7439 non-dependent types; otherwise, the lookup could not have
7440 succeeded. However, they may indicate bases of the template
7441 class, rather than the instantiated class.
7443 In addition, lookups that were not ambiguous before may be
7444 ambiguous now. Therefore, we perform the lookup again. */
7445 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7446 fns = BASELINK_FUNCTIONS (baselink);
7447 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7449 template_id_p = true;
7450 template_args = TREE_OPERAND (fns, 1);
7451 fns = TREE_OPERAND (fns, 0);
7453 template_args = tsubst_template_args (template_args, args,
7456 name = DECL_NAME (get_first_fn (fns));
7457 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7459 /* If lookup found a single function, mark it as used at this
7460 point. (If it lookup found multiple functions the one selected
7461 later by overload resolution will be marked as used at that
7463 if (BASELINK_P (baselink))
7464 fns = BASELINK_FUNCTIONS (baselink);
7465 if (!template_id_p && !really_overloaded_fn (fns))
7466 mark_used (OVL_CURRENT (fns));
7468 /* Add back the template arguments, if present. */
7469 if (BASELINK_P (baselink) && template_id_p)
7470 BASELINK_FUNCTIONS (baselink)
7471 = build_nt (TEMPLATE_ID_EXPR,
7472 BASELINK_FUNCTIONS (baselink),
7476 object_type = current_class_type;
7477 return adjust_result_of_qualified_name_lookup (baselink,
7482 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7483 true if the qualified-id will be a postfix-expression in-and-of
7484 itself; false if more of the postfix-expression follows the
7485 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7489 tsubst_qualified_id (tree qualified_id, tree args,
7490 tsubst_flags_t complain, tree in_decl,
7491 bool done, bool address_p)
7499 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7501 /* Figure out what name to look up. */
7502 name = TREE_OPERAND (qualified_id, 1);
7503 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7506 template_args = TREE_OPERAND (name, 1);
7508 template_args = tsubst_template_args (template_args, args,
7510 name = TREE_OPERAND (name, 0);
7514 is_template = false;
7515 template_args = NULL_TREE;
7518 /* Substitute into the qualifying scope. When there are no ARGS, we
7519 are just trying to simplify a non-dependent expression. In that
7520 case the qualifying scope may be dependent, and, in any case,
7521 substituting will not help. */
7522 scope = TREE_OPERAND (qualified_id, 0);
7525 scope = tsubst (scope, args, complain, in_decl);
7526 expr = tsubst_copy (name, args, complain, in_decl);
7531 if (dependent_type_p (scope))
7532 return build_nt (SCOPE_REF, scope, expr);
7534 if (!BASELINK_P (name) && !DECL_P (expr))
7536 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7537 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7538 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7540 if (complain & tf_error)
7542 error ("dependent-name %qE is parsed as a non-type, but "
7543 "instantiation yields a type", qualified_id);
7544 inform ("say %<typename %E%> if a type is meant", qualified_id);
7546 return error_mark_node;
7552 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7554 /* Remember that there was a reference to this entity. */
7558 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7560 if (complain & tf_error)
7561 qualified_name_lookup_error (scope,
7562 TREE_OPERAND (qualified_id, 1),
7564 return error_mark_node;
7568 expr = lookup_template_function (expr, template_args);
7570 if (expr == error_mark_node && complain & tf_error)
7571 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7573 else if (TYPE_P (scope))
7575 expr = (adjust_result_of_qualified_name_lookup
7576 (expr, scope, current_class_type));
7577 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7583 /* Like tsubst, but deals with expressions. This function just replaces
7584 template parms; to finish processing the resultant expression, use
7588 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7590 enum tree_code code;
7593 if (t == NULL_TREE || t == error_mark_node)
7596 code = TREE_CODE (t);
7601 r = retrieve_local_specialization (t);
7602 gcc_assert (r != NULL);
7611 if (DECL_TEMPLATE_PARM_P (t))
7612 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7613 /* There is no need to substitute into namespace-scope
7615 if (DECL_NAMESPACE_SCOPE_P (t))
7617 /* If ARGS is NULL, then T is known to be non-dependent. */
7618 if (args == NULL_TREE)
7619 return decl_constant_value (t);
7621 /* Unfortunately, we cannot just call lookup_name here.
7624 template <int I> int f() {
7626 struct S { void g() { E e = a; } };
7629 When we instantiate f<7>::S::g(), say, lookup_name is not
7630 clever enough to find f<7>::a. */
7632 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7633 /*entering_scope=*/0);
7635 for (v = TYPE_VALUES (enum_type);
7638 if (TREE_PURPOSE (v) == DECL_NAME (t))
7639 return TREE_VALUE (v);
7641 /* We didn't find the name. That should never happen; if
7642 name-lookup found it during preliminary parsing, we
7643 should find it again here during instantiation. */
7649 if (DECL_CONTEXT (t))
7653 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7654 /*entering_scope=*/1);
7655 if (ctx != DECL_CONTEXT (t))
7656 return lookup_field (ctx, DECL_NAME (t), 0, false);
7663 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7664 || local_variable_p (t))
7665 t = tsubst (t, args, complain, in_decl);
7670 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7673 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7674 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7675 args, complain, in_decl);
7676 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7677 return tsubst (t, args, complain, in_decl);
7678 else if (DECL_CLASS_SCOPE_P (t)
7679 && uses_template_parms (DECL_CONTEXT (t)))
7681 /* Template template argument like the following example need
7684 template <template <class> class TT> struct C {};
7685 template <class T> struct D {
7686 template <class U> struct E {};
7691 We are processing the template argument `E' in #1 for
7692 the template instantiation #2. Originally, `E' is a
7693 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7694 have to substitute this with one having context `D<int>'. */
7696 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7697 return lookup_field (context, DECL_NAME(t), 0, false);
7700 /* Ordinary template template argument. */
7704 case REINTERPRET_CAST_EXPR:
7705 case CONST_CAST_EXPR:
7706 case STATIC_CAST_EXPR:
7707 case DYNAMIC_CAST_EXPR:
7710 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7711 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7715 case TRUTH_NOT_EXPR:
7718 case CONVERT_EXPR: /* Unary + */
7727 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7728 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7735 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7736 name = TREE_OPERAND (t, 1);
7737 if (TREE_CODE (name) == BIT_NOT_EXPR)
7739 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7741 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7743 else if (TREE_CODE (name) == SCOPE_REF
7744 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7746 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7748 name = TREE_OPERAND (name, 1);
7749 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7751 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7752 name = build_nt (SCOPE_REF, base, name);
7754 else if (TREE_CODE (name) == BASELINK)
7755 name = tsubst_baselink (name,
7756 non_reference (TREE_TYPE (object)),
7760 name = tsubst_copy (name, args, complain, in_decl);
7761 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7767 case TRUNC_DIV_EXPR:
7769 case FLOOR_DIV_EXPR:
7770 case ROUND_DIV_EXPR:
7771 case EXACT_DIV_EXPR:
7775 case TRUNC_MOD_EXPR:
7776 case FLOOR_MOD_EXPR:
7777 case TRUTH_ANDIF_EXPR:
7778 case TRUTH_ORIF_EXPR:
7779 case TRUTH_AND_EXPR:
7798 case PREDECREMENT_EXPR:
7799 case PREINCREMENT_EXPR:
7800 case POSTDECREMENT_EXPR:
7801 case POSTINCREMENT_EXPR:
7803 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7804 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7807 return build_nt (code,
7808 tsubst_copy (TREE_OPERAND (t, 0), args,
7810 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7816 case PSEUDO_DTOR_EXPR:
7819 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7820 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7821 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7822 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7829 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7830 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7831 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7832 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7839 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7840 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7841 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7842 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7846 case TEMPLATE_ID_EXPR:
7848 /* Substituted template arguments */
7849 tree fn = TREE_OPERAND (t, 0);
7850 tree targs = TREE_OPERAND (t, 1);
7852 fn = tsubst_copy (fn, args, complain, in_decl);
7854 targs = tsubst_template_args (targs, args, complain, in_decl);
7856 return lookup_template_function (fn, targs);
7861 tree purpose, value, chain;
7863 if (t == void_list_node)
7866 purpose = TREE_PURPOSE (t);
7868 purpose = tsubst_copy (purpose, args, complain, in_decl);
7869 value = TREE_VALUE (t);
7871 value = tsubst_copy (value, args, complain, in_decl);
7872 chain = TREE_CHAIN (t);
7873 if (chain && chain != void_type_node)
7874 chain = tsubst_copy (chain, args, complain, in_decl);
7875 if (purpose == TREE_PURPOSE (t)
7876 && value == TREE_VALUE (t)
7877 && chain == TREE_CHAIN (t))
7879 return tree_cons (purpose, value, chain);
7886 case TEMPLATE_TYPE_PARM:
7887 case TEMPLATE_TEMPLATE_PARM:
7888 case BOUND_TEMPLATE_TEMPLATE_PARM:
7889 case TEMPLATE_PARM_INDEX:
7891 case REFERENCE_TYPE:
7897 case UNBOUND_CLASS_TEMPLATE:
7900 return tsubst (t, args, complain, in_decl);
7902 case IDENTIFIER_NODE:
7903 if (IDENTIFIER_TYPENAME_P (t))
7905 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7906 return mangle_conv_op_name_for_type (new_type);
7913 r = build_constructor
7914 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7915 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7916 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7921 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7923 tsubst (TREE_TYPE (t), args, complain, in_decl));
7925 case CLEANUP_POINT_EXPR:
7926 /* We shouldn't have built any of these during initial template
7927 generation. Instead, they should be built during instantiation
7928 in response to the saved STMT_IS_FULL_EXPR_P setting. */
7936 /* Like tsubst_copy for expressions, etc. but also does semantic
7940 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7944 if (t == NULL_TREE || t == error_mark_node)
7947 if (EXPR_HAS_LOCATION (t))
7948 input_location = EXPR_LOCATION (t);
7949 if (STATEMENT_CODE_P (TREE_CODE (t)))
7950 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
7952 switch (TREE_CODE (t))
7954 case STATEMENT_LIST:
7956 tree_stmt_iterator i;
7957 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
7958 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
7962 case CTOR_INITIALIZER:
7963 finish_mem_initializers (tsubst_initializer_list
7964 (TREE_OPERAND (t, 0), args));
7968 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
7969 args, complain, in_decl));
7973 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
7974 if (EXPR_STMT_STMT_EXPR_RESULT (t))
7975 finish_stmt_expr_expr (tmp, cur_stmt_expr);
7977 finish_expr_stmt (tmp);
7981 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
7982 args, complain, in_decl));
7990 decl = DECL_EXPR_DECL (t);
7991 if (TREE_CODE (decl) == LABEL_DECL)
7992 finish_label_decl (DECL_NAME (decl));
7993 else if (TREE_CODE (decl) == USING_DECL)
7995 tree scope = DECL_INITIAL (decl);
7996 tree name = DECL_NAME (decl);
7999 scope = tsubst_expr (scope, args, complain, in_decl);
8000 decl = lookup_qualified_name (scope, name,
8001 /*is_type_p=*/false,
8002 /*complain=*/false);
8003 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8004 qualified_name_lookup_error (scope, name, decl);
8006 do_local_using_decl (decl, scope, name);
8010 init = DECL_INITIAL (decl);
8011 decl = tsubst (decl, args, complain, in_decl);
8012 if (decl != error_mark_node)
8015 DECL_INITIAL (decl) = error_mark_node;
8016 /* By marking the declaration as instantiated, we avoid
8017 trying to instantiate it. Since instantiate_decl can't
8018 handle local variables, and since we've already done
8019 all that needs to be done, that's the right thing to
8021 if (TREE_CODE (decl) == VAR_DECL)
8022 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8023 if (TREE_CODE (decl) == VAR_DECL
8024 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8025 /* Anonymous aggregates are a special case. */
8026 finish_anon_union (decl);
8029 maybe_push_decl (decl);
8030 if (TREE_CODE (decl) == VAR_DECL
8031 && DECL_PRETTY_FUNCTION_P (decl))
8033 /* For __PRETTY_FUNCTION__ we have to adjust the
8035 const char *const name
8036 = cxx_printable_name (current_function_decl, 2);
8037 init = cp_fname_init (name, &TREE_TYPE (decl));
8040 init = tsubst_expr (init, args, complain, in_decl);
8041 cp_finish_decl (decl, init, NULL_TREE, 0);
8046 /* A DECL_EXPR can also be used as an expression, in the condition
8047 clause of an if/for/while construct. */
8052 stmt = begin_for_stmt ();
8053 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8054 finish_for_init_stmt (stmt);
8055 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8056 finish_for_cond (tmp, stmt);
8057 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8058 finish_for_expr (tmp, stmt);
8059 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8060 finish_for_stmt (stmt);
8064 stmt = begin_while_stmt ();
8065 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8066 finish_while_stmt_cond (tmp, stmt);
8067 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8068 finish_while_stmt (stmt);
8072 stmt = begin_do_stmt ();
8073 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8074 finish_do_body (stmt);
8075 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8076 finish_do_stmt (tmp, stmt);
8080 stmt = begin_if_stmt ();
8081 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8082 finish_if_stmt_cond (tmp, stmt);
8083 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8084 finish_then_clause (stmt);
8086 if (ELSE_CLAUSE (t))
8088 begin_else_clause (stmt);
8089 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8090 finish_else_clause (stmt);
8093 finish_if_stmt (stmt);
8097 if (BIND_EXPR_BODY_BLOCK (t))
8098 stmt = begin_function_body ();
8100 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8101 ? BCS_TRY_BLOCK : 0);
8103 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8105 if (BIND_EXPR_BODY_BLOCK (t))
8106 finish_function_body (stmt);
8108 finish_compound_stmt (stmt);
8112 finish_break_stmt ();
8116 finish_continue_stmt ();
8120 stmt = begin_switch_stmt ();
8121 tmp = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
8122 finish_switch_cond (tmp, stmt);
8123 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
8124 finish_switch_stmt (stmt);
8127 case CASE_LABEL_EXPR:
8128 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8129 tsubst_expr (CASE_HIGH (t), args, complain,
8134 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8138 tmp = GOTO_DESTINATION (t);
8139 if (TREE_CODE (tmp) != LABEL_DECL)
8140 /* Computed goto's must be tsubst'd into. On the other hand,
8141 non-computed gotos must not be; the identifier in question
8142 will have no binding. */
8143 tmp = tsubst_expr (tmp, args, complain, in_decl);
8145 tmp = DECL_NAME (tmp);
8146 finish_goto_stmt (tmp);
8150 tmp = finish_asm_stmt
8151 (ASM_VOLATILE_P (t),
8152 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8153 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8154 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8155 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8157 tree asm_expr = tmp;
8158 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8159 asm_expr = TREE_OPERAND (asm_expr, 0);
8160 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8167 stmt = begin_try_block ();
8168 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8169 finish_cleanup_try_block (stmt);
8170 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8176 if (FN_TRY_BLOCK_P (t))
8177 stmt = begin_function_try_block ();
8179 stmt = begin_try_block ();
8181 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8183 if (FN_TRY_BLOCK_P (t))
8184 finish_function_try_block (stmt);
8186 finish_try_block (stmt);
8188 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8189 if (FN_TRY_BLOCK_P (t))
8190 finish_function_handler_sequence (stmt);
8192 finish_handler_sequence (stmt);
8200 stmt = begin_handler ();
8201 if (HANDLER_PARMS (t))
8203 decl = HANDLER_PARMS (t);
8204 decl = tsubst (decl, args, complain, in_decl);
8205 /* Prevent instantiate_decl from trying to instantiate
8206 this variable. We've already done all that needs to be
8208 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8212 finish_handler_parms (decl, stmt);
8213 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8214 finish_handler (stmt);
8219 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8223 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8225 return tsubst_copy_and_build (t, args, complain, in_decl,
8226 /*function_p=*/false);
8232 /* T is a postfix-expression that is not being used in a function
8233 call. Return the substituted version of T. */
8236 tsubst_non_call_postfix_expression (tree t, tree args,
8237 tsubst_flags_t complain,
8240 if (TREE_CODE (t) == SCOPE_REF)
8241 t = tsubst_qualified_id (t, args, complain, in_decl,
8242 /*done=*/false, /*address_p=*/false);
8244 t = tsubst_copy_and_build (t, args, complain, in_decl,
8245 /*function_p=*/false);
8250 /* Like tsubst but deals with expressions and performs semantic
8251 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8254 tsubst_copy_and_build (tree t,
8256 tsubst_flags_t complain,
8260 #define RECUR(NODE) \
8261 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8265 if (t == NULL_TREE || t == error_mark_node)
8268 switch (TREE_CODE (t))
8273 case IDENTIFIER_NODE:
8277 tree qualifying_class;
8278 bool non_integral_constant_expression_p;
8279 const char *error_msg;
8281 if (IDENTIFIER_TYPENAME_P (t))
8283 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8284 t = mangle_conv_op_name_for_type (new_type);
8287 /* Look up the name. */
8288 decl = lookup_name (t, 0);
8290 /* By convention, expressions use ERROR_MARK_NODE to indicate
8291 failure, not NULL_TREE. */
8292 if (decl == NULL_TREE)
8293 decl = error_mark_node;
8295 decl = finish_id_expression (t, decl, NULL_TREE,
8298 /*integral_constant_expression_p=*/false,
8299 /*allow_non_integral_constant_expression_p=*/false,
8300 &non_integral_constant_expression_p,
8304 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8305 decl = unqualified_name_lookup_error (decl);
8309 case TEMPLATE_ID_EXPR:
8312 tree template = RECUR (TREE_OPERAND (t, 0));
8313 tree targs = TREE_OPERAND (t, 1);
8316 targs = tsubst_template_args (targs, args, complain, in_decl);
8318 if (TREE_CODE (template) == COMPONENT_REF)
8320 object = TREE_OPERAND (template, 0);
8321 template = TREE_OPERAND (template, 1);
8325 template = lookup_template_function (template, targs);
8328 return build3 (COMPONENT_REF, TREE_TYPE (template),
8329 object, template, NULL_TREE);
8335 return build_x_indirect_ref (RECUR (TREE_OPERAND (t, 0)), "unary *");
8339 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8340 RECUR (TREE_OPERAND (t, 0)));
8343 return build_functional_cast
8344 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8345 RECUR (TREE_OPERAND (t, 0)));
8347 case REINTERPRET_CAST_EXPR:
8348 return build_reinterpret_cast
8349 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8350 RECUR (TREE_OPERAND (t, 0)));
8352 case CONST_CAST_EXPR:
8353 return build_const_cast
8354 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8355 RECUR (TREE_OPERAND (t, 0)));
8357 case DYNAMIC_CAST_EXPR:
8358 return build_dynamic_cast
8359 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8360 RECUR (TREE_OPERAND (t, 0)));
8362 case STATIC_CAST_EXPR:
8363 return build_static_cast
8364 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8365 RECUR (TREE_OPERAND (t, 0)));
8367 case POSTDECREMENT_EXPR:
8368 case POSTINCREMENT_EXPR:
8369 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8370 args, complain, in_decl);
8371 return build_x_unary_op (TREE_CODE (t), op1);
8373 case PREDECREMENT_EXPR:
8374 case PREINCREMENT_EXPR:
8378 case TRUTH_NOT_EXPR:
8379 case CONVERT_EXPR: /* Unary + */
8382 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8385 op1 = TREE_OPERAND (t, 0);
8386 if (TREE_CODE (op1) == SCOPE_REF)
8387 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8388 /*done=*/true, /*address_p=*/true);
8390 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8392 if (TREE_CODE (op1) == LABEL_DECL)
8393 return finish_label_address_expr (DECL_NAME (op1));
8394 return build_x_unary_op (ADDR_EXPR, op1);
8399 case TRUNC_DIV_EXPR:
8401 case FLOOR_DIV_EXPR:
8402 case ROUND_DIV_EXPR:
8403 case EXACT_DIV_EXPR:
8407 case TRUNC_MOD_EXPR:
8408 case FLOOR_MOD_EXPR:
8409 case TRUTH_ANDIF_EXPR:
8410 case TRUTH_ORIF_EXPR:
8411 case TRUTH_AND_EXPR:
8427 return build_x_binary_op
8429 RECUR (TREE_OPERAND (t, 0)),
8430 RECUR (TREE_OPERAND (t, 1)),
8431 /*overloaded_p=*/NULL);
8434 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8435 /*address_p=*/false);
8438 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8441 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)),
8442 NULL_TREE, NULL_TREE);
8444 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8445 args, complain, in_decl);
8446 /* Remember that there was a reference to this entity. */
8449 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8453 op1 = TREE_OPERAND (t, 0);
8456 /* When there are no ARGS, we are trying to evaluate a
8457 non-dependent expression from the parser. Trying to do
8458 the substitutions may not work. */
8460 op1 = TREE_TYPE (op1);
8469 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8471 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8475 tree r = build_x_modify_expr
8476 (RECUR (TREE_OPERAND (t, 0)),
8477 TREE_CODE (TREE_OPERAND (t, 1)),
8478 RECUR (TREE_OPERAND (t, 2)));
8479 /* TREE_NO_WARNING must be set if either the expression was
8480 parenthesized or it uses an operator such as >>= rather
8481 than plain assignment. In the former case, it was already
8482 set and must be copied. In the latter case,
8483 build_x_modify_expr sets it and it must not be reset
8485 if (TREE_NO_WARNING (t))
8486 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8491 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8492 args, complain, in_decl);
8493 /* Remember that there was a reference to this entity. */
8496 return build_x_arrow (op1);
8500 (RECUR (TREE_OPERAND (t, 0)),
8501 RECUR (TREE_OPERAND (t, 1)),
8502 RECUR (TREE_OPERAND (t, 2)),
8503 RECUR (TREE_OPERAND (t, 3)),
8504 NEW_EXPR_USE_GLOBAL (t));
8507 return delete_sanity
8508 (RECUR (TREE_OPERAND (t, 0)),
8509 RECUR (TREE_OPERAND (t, 1)),
8510 DELETE_EXPR_USE_VEC (t),
8511 DELETE_EXPR_USE_GLOBAL (t));
8514 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8515 RECUR (TREE_OPERAND (t, 1)));
8524 function = TREE_OPERAND (t, 0);
8525 /* When we parsed the expression, we determined whether or
8526 not Koenig lookup should be performed. */
8527 koenig_p = KOENIG_LOOKUP_P (t);
8528 if (TREE_CODE (function) == SCOPE_REF)
8531 function = tsubst_qualified_id (function, args, complain, in_decl,
8533 /*address_p=*/false);
8537 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8538 && (TREE_CODE (TREE_OPERAND (function, 1))
8540 function = tsubst_copy_and_build (function, args, complain,
8543 if (BASELINK_P (function))
8547 call_args = RECUR (TREE_OPERAND (t, 1));
8549 /* We do not perform argument-dependent lookup if normal
8550 lookup finds a non-function, in accordance with the
8551 expected resolution of DR 218. */
8553 && (is_overloaded_fn (function)
8554 || TREE_CODE (function) == IDENTIFIER_NODE))
8555 function = perform_koenig_lookup (function, call_args);
8557 if (TREE_CODE (function) == IDENTIFIER_NODE)
8559 unqualified_name_lookup_error (function);
8560 return error_mark_node;
8563 /* Remember that there was a reference to this entity. */
8564 if (DECL_P (function))
8565 mark_used (function);
8567 function = convert_from_reference (function);
8569 if (TREE_CODE (function) == OFFSET_REF)
8570 return build_offset_ref_call_from_tree (function, call_args);
8571 if (TREE_CODE (function) == COMPONENT_REF)
8573 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8574 return finish_call_expr (function, call_args,
8575 /*disallow_virtual=*/false,
8576 /*koenig_p=*/false);
8578 return (build_new_method_call
8579 (TREE_OPERAND (function, 0),
8580 TREE_OPERAND (function, 1),
8581 call_args, NULL_TREE,
8582 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8584 return finish_call_expr (function, call_args,
8585 /*disallow_virtual=*/qualified_p,
8590 return build_x_conditional_expr
8591 (RECUR (TREE_OPERAND (t, 0)),
8592 RECUR (TREE_OPERAND (t, 1)),
8593 RECUR (TREE_OPERAND (t, 2)));
8595 case PSEUDO_DTOR_EXPR:
8596 return finish_pseudo_destructor_expr
8597 (RECUR (TREE_OPERAND (t, 0)),
8598 RECUR (TREE_OPERAND (t, 1)),
8599 RECUR (TREE_OPERAND (t, 2)));
8603 tree purpose, value, chain;
8605 if (t == void_list_node)
8608 purpose = TREE_PURPOSE (t);
8610 purpose = RECUR (purpose);
8611 value = TREE_VALUE (t);
8613 value = RECUR (value);
8614 chain = TREE_CHAIN (t);
8615 if (chain && chain != void_type_node)
8616 chain = RECUR (chain);
8617 if (purpose == TREE_PURPOSE (t)
8618 && value == TREE_VALUE (t)
8619 && chain == TREE_CHAIN (t))
8621 return tree_cons (purpose, value, chain);
8629 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8630 args, complain, in_decl);
8631 /* Remember that there was a reference to this entity. */
8632 if (DECL_P (object))
8635 member = TREE_OPERAND (t, 1);
8636 if (BASELINK_P (member))
8637 member = tsubst_baselink (member,
8638 non_reference (TREE_TYPE (object)),
8639 args, complain, in_decl);
8641 member = tsubst_copy (member, args, complain, in_decl);
8643 if (!CLASS_TYPE_P (TREE_TYPE (object)))
8645 if (TREE_CODE (member) == BIT_NOT_EXPR)
8646 return finish_pseudo_destructor_expr (object,
8648 TREE_TYPE (object));
8649 else if (TREE_CODE (member) == SCOPE_REF
8650 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8651 return finish_pseudo_destructor_expr (object,
8653 TREE_TYPE (object));
8655 else if (TREE_CODE (member) == SCOPE_REF
8656 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8661 /* Lookup the template functions now that we know what the
8663 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8664 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8665 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8666 /*is_type_p=*/false,
8667 /*complain=*/false);
8668 if (BASELINK_P (member))
8669 BASELINK_FUNCTIONS (member)
8670 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8674 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8676 return error_mark_node;
8679 else if (TREE_CODE (member) == SCOPE_REF
8680 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8681 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8683 if (complain & tf_error)
8685 if (TYPE_P (TREE_OPERAND (member, 0)))
8686 error ("%qT is not a class or namespace",
8687 TREE_OPERAND (member, 0));
8689 error ("%qD is not a class or namespace",
8690 TREE_OPERAND (member, 0));
8692 return error_mark_node;
8694 else if (TREE_CODE (member) == FIELD_DECL)
8695 return finish_non_static_data_member (member, object, NULL_TREE);
8697 return finish_class_member_access_expr (object, member);
8702 (RECUR (TREE_OPERAND (t, 0)));
8708 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8711 /* digest_init will do the wrong thing if we let it. */
8712 if (type && TYPE_PTRMEMFUNC_P (type))
8716 /* We do not want to process the purpose of aggregate
8717 initializers as they are identifier nodes which will be
8718 looked up by digest_init. */
8719 purpose_p = !(type && IS_AGGR_TYPE (type));
8720 for (elts = CONSTRUCTOR_ELTS (t);
8722 elts = TREE_CHAIN (elts))
8724 tree purpose = TREE_PURPOSE (elts);
8725 tree value = TREE_VALUE (elts);
8727 if (purpose && purpose_p)
8728 purpose = RECUR (purpose);
8729 value = RECUR (value);
8730 r = tree_cons (purpose, value, r);
8733 r = build_constructor (NULL_TREE, nreverse (r));
8734 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8737 return digest_init (type, r, 0);
8743 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8744 if (TYPE_P (operand_0))
8745 return get_typeid (operand_0);
8746 return build_typeid (operand_0);
8750 return convert_from_reference (tsubst_copy (t, args, complain, in_decl));
8754 t = tsubst_copy (t, args, complain, in_decl);
8755 return convert_from_reference (t);
8758 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8759 tsubst_copy (TREE_TYPE (t), args, complain,
8763 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8767 tree old_stmt_expr = cur_stmt_expr;
8768 tree stmt_expr = begin_stmt_expr ();
8770 cur_stmt_expr = stmt_expr;
8771 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8772 stmt_expr = finish_stmt_expr (stmt_expr, false);
8773 cur_stmt_expr = old_stmt_expr;
8779 t = tsubst_copy (t, args, complain, in_decl);
8780 /* As in finish_id_expression, we resolve enumeration constants
8781 to their underlying values. */
8782 if (TREE_CODE (t) == CONST_DECL)
8783 return DECL_INITIAL (t);
8787 return tsubst_copy (t, args, complain, in_decl);
8793 /* Verify that the instantiated ARGS are valid. For type arguments,
8794 make sure that the type's linkage is ok. For non-type arguments,
8795 make sure they are constants if they are integral or enumerations.
8796 Emit an error under control of COMPLAIN, and return TRUE on error. */
8799 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8801 int ix, len = DECL_NTPARMS (tmpl);
8802 bool result = false;
8804 for (ix = 0; ix != len; ix++)
8806 tree t = TREE_VEC_ELT (args, ix);
8810 /* [basic.link]: A name with no linkage (notably, the name
8811 of a class or enumeration declared in a local scope)
8812 shall not be used to declare an entity with linkage.
8813 This implies that names with no linkage cannot be used as
8814 template arguments. */
8815 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8819 if (!(complain & tf_error))
8821 else if (TYPE_ANONYMOUS_P (nt))
8822 error ("%qT uses anonymous type", t);
8824 error ("%qT uses local type %qT", t, nt);
8827 /* In order to avoid all sorts of complications, we do not
8828 allow variably-modified types as template arguments. */
8829 else if (variably_modified_type_p (t, NULL_TREE))
8831 if (complain & tf_error)
8832 error ("%qT is a variably modified type", t);
8836 /* A non-type argument of integral or enumerated type must be a
8838 else if (TREE_TYPE (t)
8839 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8840 && !TREE_CONSTANT (t))
8842 if (complain & tf_error)
8843 error ("integral expression %qE is not constant", t);
8847 if (result && complain & tf_error)
8848 error (" trying to instantiate %qD", tmpl);
8852 /* Instantiate the indicated variable or function template TMPL with
8853 the template arguments in TARG_PTR. */
8856 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8862 if (tmpl == error_mark_node)
8863 return error_mark_node;
8865 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
8867 /* If this function is a clone, handle it specially. */
8868 if (DECL_CLONED_FUNCTION_P (tmpl))
8873 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8875 if (spec == error_mark_node)
8876 return error_mark_node;
8878 /* Look for the clone. */
8879 FOR_EACH_CLONE (clone, spec)
8880 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8882 /* We should always have found the clone by now. */
8887 /* Check to see if we already have this specialization. */
8888 spec = retrieve_specialization (tmpl, targ_ptr,
8889 /*class_specializations_p=*/false);
8890 if (spec != NULL_TREE)
8893 gen_tmpl = most_general_template (tmpl);
8894 if (tmpl != gen_tmpl)
8896 /* The TMPL is a partial instantiation. To get a full set of
8897 arguments we must add the arguments used to perform the
8898 partial instantiation. */
8899 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
8902 /* Check to see if we already have this specialization. */
8903 spec = retrieve_specialization (gen_tmpl, targ_ptr,
8904 /*class_specializations_p=*/false);
8905 if (spec != NULL_TREE)
8909 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
8911 return error_mark_node;
8913 /* We are building a FUNCTION_DECL, during which the access of its
8914 parameters and return types have to be checked. However this
8915 FUNCTION_DECL which is the desired context for access checking
8916 is not built yet. We solve this chicken-and-egg problem by
8917 deferring all checks until we have the FUNCTION_DECL. */
8918 push_deferring_access_checks (dk_deferred);
8920 /* Substitute template parameters. */
8921 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
8922 targ_ptr, complain, gen_tmpl);
8924 /* Now we know the specialization, compute access previously
8926 push_access_scope (fndecl);
8927 perform_deferred_access_checks ();
8928 pop_access_scope (fndecl);
8929 pop_deferring_access_checks ();
8931 /* The DECL_TI_TEMPLATE should always be the immediate parent
8932 template, not the most general template. */
8933 DECL_TI_TEMPLATE (fndecl) = tmpl;
8935 /* If we've just instantiated the main entry point for a function,
8936 instantiate all the alternate entry points as well. We do this
8937 by cloning the instantiation of the main entry point, not by
8938 instantiating the template clones. */
8939 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
8940 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
8945 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8946 arguments that are being used when calling it. TARGS is a vector
8947 into which the deduced template arguments are placed.
8949 Return zero for success, 2 for an incomplete match that doesn't resolve
8950 all the types, and 1 for complete failure. An error message will be
8951 printed only for an incomplete match.
8953 If FN is a conversion operator, or we are trying to produce a specific
8954 specialization, RETURN_TYPE is the return type desired.
8956 The EXPLICIT_TARGS are explicit template arguments provided via a
8959 The parameter STRICT is one of:
8962 We are deducing arguments for a function call, as in
8966 We are deducing arguments for a conversion function, as in
8970 We are deducing arguments when doing an explicit instantiation
8971 as in [temp.explicit], when determining an explicit specialization
8972 as in [temp.expl.spec], or when taking the address of a function
8973 template, as in [temp.deduct.funcaddr].
8976 We are deducing arguments when calculating the partial
8977 ordering between specializations of function or class
8978 templates, as in [temp.func.order] and [temp.class.order].
8980 LEN is the number of parms to consider before returning success, or -1
8981 for all. This is used in partial ordering to avoid comparing parms for
8982 which no actual argument was passed, since they are not considered in
8983 overload resolution (and are explicitly excluded from consideration in
8984 partial ordering in [temp.func.order]/6). */
8987 fn_type_unification (tree fn,
8988 tree explicit_targs,
8992 unification_kind_t strict,
8999 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9001 fntype = TREE_TYPE (fn);
9006 The specified template arguments must match the template
9007 parameters in kind (i.e., type, nontype, template), and there
9008 must not be more arguments than there are parameters;
9009 otherwise type deduction fails.
9011 Nontype arguments must match the types of the corresponding
9012 nontype template parameters, or must be convertible to the
9013 types of the corresponding nontype parameters as specified in
9014 _temp.arg.nontype_, otherwise type deduction fails.
9016 All references in the function type of the function template
9017 to the corresponding template parameters are replaced by the
9018 specified template argument values. If a substitution in a
9019 template parameter or in the function type of the function
9020 template results in an invalid type, type deduction fails. */
9022 tree converted_args;
9026 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9027 explicit_targs, NULL_TREE, tf_none,
9028 /*require_all_arguments=*/0));
9029 if (converted_args == error_mark_node)
9032 /* Substitute the explicit args into the function type. This is
9033 necessary so that, for instance, explicitly declared function
9034 arguments can match null pointed constants. If we were given
9035 an incomplete set of explicit args, we must not do semantic
9036 processing during substitution as we could create partial
9038 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9039 processing_template_decl += incomplete;
9040 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9041 processing_template_decl -= incomplete;
9043 if (fntype == error_mark_node)
9046 /* Place the explicitly specified arguments in TARGS. */
9047 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9048 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9051 parms = TYPE_ARG_TYPES (fntype);
9052 /* Never do unification on the 'this' parameter. */
9053 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9054 parms = TREE_CHAIN (parms);
9058 /* We've been given a return type to match, prepend it. */
9059 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9060 args = tree_cons (NULL_TREE, return_type, args);
9065 /* We allow incomplete unification without an error message here
9066 because the standard doesn't seem to explicitly prohibit it. Our
9067 callers must be ready to deal with unification failures in any
9069 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9070 targs, parms, args, /*subr=*/0,
9071 strict, /*allow_incomplete*/1, len);
9074 /* All is well so far. Now, check:
9078 When all template arguments have been deduced, all uses of
9079 template parameters in nondeduced contexts are replaced with
9080 the corresponding deduced argument values. If the
9081 substitution results in an invalid type, as described above,
9082 type deduction fails. */
9083 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9090 /* Adjust types before performing type deduction, as described in
9091 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9092 sections are symmetric. PARM is the type of a function parameter
9093 or the return type of the conversion function. ARG is the type of
9094 the argument passed to the call, or the type of the value
9095 initialized with the result of the conversion function. */
9098 maybe_adjust_types_for_deduction (unification_kind_t strict,
9111 /* Swap PARM and ARG throughout the remainder of this
9112 function; the handling is precisely symmetric since PARM
9113 will initialize ARG rather than vice versa. */
9121 /* There is nothing to do in this case. */
9125 /* DR 214. [temp.func.order] is underspecified, and leads to no
9126 ordering between things like `T *' and `T const &' for `U *'.
9127 The former has T=U and the latter T=U*. The former looks more
9128 specialized and John Spicer considers it well-formed (the EDG
9129 compiler accepts it).
9131 John also confirms that deduction should proceed as in a function
9132 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
9133 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
9134 to an actual call can have such a type.
9136 If both ARG and PARM are REFERENCE_TYPE, we change neither.
9137 If only ARG is a REFERENCE_TYPE, we look through that and then
9138 proceed as with DEDUCE_CALL (which could further convert it). */
9139 if (TREE_CODE (*arg) == REFERENCE_TYPE)
9141 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9143 *arg = TREE_TYPE (*arg);
9150 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9152 /* [temp.deduct.call]
9154 If P is not a reference type:
9156 --If A is an array type, the pointer type produced by the
9157 array-to-pointer standard conversion (_conv.array_) is
9158 used in place of A for type deduction; otherwise,
9160 --If A is a function type, the pointer type produced by
9161 the function-to-pointer standard conversion
9162 (_conv.func_) is used in place of A for type deduction;
9165 --If A is a cv-qualified type, the top level
9166 cv-qualifiers of A's type are ignored for type
9168 if (TREE_CODE (*arg) == ARRAY_TYPE)
9169 *arg = build_pointer_type (TREE_TYPE (*arg));
9170 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9171 *arg = build_pointer_type (*arg);
9173 *arg = TYPE_MAIN_VARIANT (*arg);
9176 /* [temp.deduct.call]
9178 If P is a cv-qualified type, the top level cv-qualifiers
9179 of P's type are ignored for type deduction. If P is a
9180 reference type, the type referred to by P is used for
9182 *parm = TYPE_MAIN_VARIANT (*parm);
9183 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9185 *parm = TREE_TYPE (*parm);
9186 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9189 /* DR 322. For conversion deduction, remove a reference type on parm
9190 too (which has been swapped into ARG). */
9191 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9192 *arg = TREE_TYPE (*arg);
9197 /* Most parms like fn_type_unification.
9199 If SUBR is 1, we're being called recursively (to unify the
9200 arguments of a function or method parameter of a function
9204 type_unification_real (tree tparms,
9209 unification_kind_t strict,
9210 int allow_incomplete,
9215 int ntparms = TREE_VEC_LENGTH (tparms);
9217 int saw_undeduced = 0;
9221 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9222 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9223 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9224 gcc_assert (ntparms > 0);
9229 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9230 | UNIFY_ALLOW_DERIVED);
9234 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9238 sub_strict = UNIFY_ALLOW_NONE;
9242 sub_strict = UNIFY_ALLOW_NONE;
9258 && parms != void_list_node
9260 && args != void_list_node)
9262 parm = TREE_VALUE (parms);
9263 parms = TREE_CHAIN (parms);
9264 arg = TREE_VALUE (args);
9265 args = TREE_CHAIN (args);
9267 if (arg == error_mark_node)
9269 if (arg == unknown_type_node)
9270 /* We can't deduce anything from this, but we might get all the
9271 template args from other function args. */
9274 /* Conversions will be performed on a function argument that
9275 corresponds with a function parameter that contains only
9276 non-deducible template parameters and explicitly specified
9277 template parameters. */
9278 if (!uses_template_parms (parm))
9283 type = TREE_TYPE (arg);
9287 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
9289 if (same_type_p (parm, type))
9293 /* It might work; we shouldn't check now, because we might
9294 get into infinite recursion. Overload resolution will
9303 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9304 if (type_unknown_p (arg))
9306 /* [temp.deduct.type] A template-argument can be deduced from
9307 a pointer to function or pointer to member function
9308 argument if the set of overloaded functions does not
9309 contain function templates and at most one of a set of
9310 overloaded functions provides a unique match. */
9312 if (resolve_overloaded_unification
9313 (tparms, targs, parm, arg, strict, sub_strict)
9318 arg = TREE_TYPE (arg);
9319 if (arg == error_mark_node)
9324 int arg_strict = sub_strict;
9327 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9329 if (unify (tparms, targs, parm, arg, arg_strict))
9333 /* Are we done with the interesting parms? */
9337 /* Fail if we've reached the end of the parm list, and more args
9338 are present, and the parm list isn't variadic. */
9339 if (args && args != void_list_node && parms == void_list_node)
9341 /* Fail if parms are left and they don't have default values. */
9343 && parms != void_list_node
9344 && TREE_PURPOSE (parms) == NULL_TREE)
9349 for (i = 0; i < ntparms; i++)
9350 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
9352 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9354 /* If this is an undeduced nontype parameter that depends on
9355 a type parameter, try another pass; its type may have been
9356 deduced from a later argument than the one from which
9357 this parameter can be deduced. */
9358 if (TREE_CODE (tparm) == PARM_DECL
9359 && uses_template_parms (TREE_TYPE (tparm))
9360 && !saw_undeduced++)
9363 if (!allow_incomplete)
9364 error ("incomplete type unification");
9370 /* Subroutine of type_unification_real. Args are like the variables at the
9371 call site. ARG is an overloaded function (or template-id); we try
9372 deducing template args from each of the overloads, and if only one
9373 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9376 resolve_overloaded_unification (tree tparms,
9380 unification_kind_t strict,
9383 tree tempargs = copy_node (targs);
9387 if (TREE_CODE (arg) == ADDR_EXPR)
9389 arg = TREE_OPERAND (arg, 0);
9395 if (TREE_CODE (arg) == COMPONENT_REF)
9396 /* Handle `&x' where `x' is some static or non-static member
9398 arg = TREE_OPERAND (arg, 1);
9400 if (TREE_CODE (arg) == OFFSET_REF)
9401 arg = TREE_OPERAND (arg, 1);
9403 /* Strip baselink information. */
9404 if (BASELINK_P (arg))
9405 arg = BASELINK_FUNCTIONS (arg);
9407 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9409 /* If we got some explicit template args, we need to plug them into
9410 the affected templates before we try to unify, in case the
9411 explicit args will completely resolve the templates in question. */
9413 tree expl_subargs = TREE_OPERAND (arg, 1);
9414 arg = TREE_OPERAND (arg, 0);
9416 for (; arg; arg = OVL_NEXT (arg))
9418 tree fn = OVL_CURRENT (arg);
9421 if (TREE_CODE (fn) != TEMPLATE_DECL)
9424 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
9428 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9429 good += try_one_overload (tparms, targs, tempargs, parm,
9430 elem, strict, sub_strict, addr_p);
9436 gcc_assert (TREE_CODE (arg) == OVERLOAD
9437 || TREE_CODE (arg) == FUNCTION_DECL);
9439 for (; arg; arg = OVL_NEXT (arg))
9440 good += try_one_overload (tparms, targs, tempargs, parm,
9441 TREE_TYPE (OVL_CURRENT (arg)),
9442 strict, sub_strict, addr_p);
9445 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9446 to function or pointer to member function argument if the set of
9447 overloaded functions does not contain function templates and at most
9448 one of a set of overloaded functions provides a unique match.
9450 So if we found multiple possibilities, we return success but don't
9455 int i = TREE_VEC_LENGTH (targs);
9457 if (TREE_VEC_ELT (tempargs, i))
9458 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9466 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9467 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9468 different overloads deduce different arguments for a given parm.
9469 ADDR_P is true if the expression for which deduction is being
9470 performed was of the form "& fn" rather than simply "fn".
9472 Returns 1 on success. */
9475 try_one_overload (tree tparms,
9480 unification_kind_t strict,
9488 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9489 to function or pointer to member function argument if the set of
9490 overloaded functions does not contain function templates and at most
9491 one of a set of overloaded functions provides a unique match.
9493 So if this is a template, just return success. */
9495 if (uses_template_parms (arg))
9498 if (TREE_CODE (arg) == METHOD_TYPE)
9499 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9501 arg = build_pointer_type (arg);
9503 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9505 /* We don't copy orig_targs for this because if we have already deduced
9506 some template args from previous args, unify would complain when we
9507 try to deduce a template parameter for the same argument, even though
9508 there isn't really a conflict. */
9509 nargs = TREE_VEC_LENGTH (targs);
9510 tempargs = make_tree_vec (nargs);
9512 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9515 /* First make sure we didn't deduce anything that conflicts with
9516 explicitly specified args. */
9517 for (i = nargs; i--; )
9519 tree elt = TREE_VEC_ELT (tempargs, i);
9520 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9522 if (elt == NULL_TREE)
9524 else if (uses_template_parms (elt))
9526 /* Since we're unifying against ourselves, we will fill in template
9527 args used in the function parm list with our own template parms.
9529 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9532 else if (oldelt && ! template_args_equal (oldelt, elt))
9536 for (i = nargs; i--; )
9538 tree elt = TREE_VEC_ELT (tempargs, i);
9541 TREE_VEC_ELT (targs, i) = elt;
9547 /* Verify that nondeduce template argument agrees with the type
9548 obtained from argument deduction. Return nonzero if the
9553 struct A { typedef int X; };
9554 template <class T, class U> struct C {};
9555 template <class T> struct C<T, typename T::X> {};
9557 Then with the instantiation `C<A, int>', we can deduce that
9558 `T' is `A' but unify () does not check whether `typename T::X'
9559 is `int'. This function ensure that they agree.
9561 TARGS, PARMS are the same as the arguments of unify.
9562 ARGS contains template arguments from all levels. */
9565 verify_class_unification (tree targs, tree parms, tree args)
9567 parms = tsubst (parms, add_outermost_template_args (args, targs),
9568 tf_none, NULL_TREE);
9569 if (parms == error_mark_node)
9572 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9575 /* PARM is a template class (perhaps with unbound template
9576 parameters). ARG is a fully instantiated type. If ARG can be
9577 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9578 TARGS are as for unify. */
9581 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9585 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9586 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9587 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9590 /* We need to make a new template argument vector for the call to
9591 unify. If we used TARGS, we'd clutter it up with the result of
9592 the attempted unification, even if this class didn't work out.
9593 We also don't want to commit ourselves to all the unifications
9594 we've already done, since unification is supposed to be done on
9595 an argument-by-argument basis. In other words, consider the
9596 following pathological case:
9598 template <int I, int J, int K>
9601 template <int I, int J>
9602 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9604 template <int I, int J, int K>
9605 void f(S<I, J, K>, S<I, I, I>);
9614 Now, by the time we consider the unification involving `s2', we
9615 already know that we must have `f<0, 0, 0>'. But, even though
9616 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9617 because there are two ways to unify base classes of S<0, 1, 2>
9618 with S<I, I, I>. If we kept the already deduced knowledge, we
9619 would reject the possibility I=1. */
9620 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9622 /* If unification failed, we're done. */
9623 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9624 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9630 /* Given a template type PARM and a class type ARG, find the unique
9631 base type in ARG that is an instance of PARM. We do not examine
9632 ARG itself; only its base-classes. If there is not exactly one
9633 appropriate base class, return NULL_TREE. PARM may be the type of
9634 a partial specialization, as well as a plain template type. Used
9638 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9640 tree rval = NULL_TREE;
9643 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9645 binfo = TYPE_BINFO (complete_type (arg));
9647 /* The type could not be completed. */
9650 /* Walk in inheritance graph order. The search order is not
9651 important, and this avoids multiple walks of virtual bases. */
9652 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9654 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9658 /* If there is more than one satisfactory baseclass, then:
9662 If they yield more than one possible deduced A, the type
9666 if (rval && !same_type_p (r, rval))
9676 /* Returns the level of DECL, which declares a template parameter. */
9679 template_decl_level (tree decl)
9681 switch (TREE_CODE (decl))
9685 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9688 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9696 /* Decide whether ARG can be unified with PARM, considering only the
9697 cv-qualifiers of each type, given STRICT as documented for unify.
9698 Returns nonzero iff the unification is OK on that basis. */
9701 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9703 int arg_quals = cp_type_quals (arg);
9704 int parm_quals = cp_type_quals (parm);
9706 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9707 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9709 /* Although a CVR qualifier is ignored when being applied to a
9710 substituted template parameter ([8.3.2]/1 for example), that
9711 does not apply during deduction [14.8.2.4]/1, (even though
9712 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9713 this). Except when we're allowing additional CV qualifiers
9714 at the outer level [14.8.2.1]/3,1st bullet. */
9715 if ((TREE_CODE (arg) == REFERENCE_TYPE
9716 || TREE_CODE (arg) == FUNCTION_TYPE
9717 || TREE_CODE (arg) == METHOD_TYPE)
9718 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9721 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9722 && (parm_quals & TYPE_QUAL_RESTRICT))
9726 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9727 && (arg_quals & parm_quals) != parm_quals)
9730 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9731 && (parm_quals & arg_quals) != arg_quals)
9737 /* Takes parameters as for type_unification. Returns 0 if the
9738 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9739 bitwise or of the following flags:
9742 Require an exact match between PARM and ARG.
9743 UNIFY_ALLOW_MORE_CV_QUAL:
9744 Allow the deduced ARG to be more cv-qualified (by qualification
9745 conversion) than ARG.
9746 UNIFY_ALLOW_LESS_CV_QUAL:
9747 Allow the deduced ARG to be less cv-qualified than ARG.
9748 UNIFY_ALLOW_DERIVED:
9749 Allow the deduced ARG to be a template base class of ARG,
9750 or a pointer to a template base class of the type pointed to by
9752 UNIFY_ALLOW_INTEGER:
9753 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9754 case for more information.
9755 UNIFY_ALLOW_OUTER_LEVEL:
9756 This is the outermost level of a deduction. Used to determine validity
9757 of qualification conversions. A valid qualification conversion must
9758 have const qualified pointers leading up to the inner type which
9759 requires additional CV quals, except at the outer level, where const
9760 is not required [conv.qual]. It would be normal to set this flag in
9761 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9762 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9763 This is the outermost level of a deduction, and PARM can be more CV
9764 qualified at this point.
9765 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9766 This is the outermost level of a deduction, and PARM can be less CV
9767 qualified at this point. */
9770 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9775 int strict_in = strict;
9777 /* I don't think this will do the right thing with respect to types.
9778 But the only case I've seen it in so far has been array bounds, where
9779 signedness is the only information lost, and I think that will be
9781 while (TREE_CODE (parm) == NOP_EXPR)
9782 parm = TREE_OPERAND (parm, 0);
9784 if (arg == error_mark_node)
9786 if (arg == unknown_type_node)
9787 /* We can't deduce anything from this, but we might get all the
9788 template args from other function args. */
9791 /* If PARM uses template parameters, then we can't bail out here,
9792 even if ARG == PARM, since we won't record unifications for the
9793 template parameters. We might need them if we're trying to
9794 figure out which of two things is more specialized. */
9795 if (arg == parm && !uses_template_parms (parm))
9798 /* Immediately reject some pairs that won't unify because of
9799 cv-qualification mismatches. */
9800 if (TREE_CODE (arg) == TREE_CODE (parm)
9802 /* It is the elements of the array which hold the cv quals of an array
9803 type, and the elements might be template type parms. We'll check
9805 && TREE_CODE (arg) != ARRAY_TYPE
9806 /* We check the cv-qualifiers when unifying with template type
9807 parameters below. We want to allow ARG `const T' to unify with
9808 PARM `T' for example, when computing which of two templates
9809 is more specialized, for example. */
9810 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9811 && !check_cv_quals_for_unify (strict_in, arg, parm))
9814 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9815 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9816 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9817 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9818 strict &= ~UNIFY_ALLOW_DERIVED;
9819 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9820 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9822 switch (TREE_CODE (parm))
9826 case UNBOUND_CLASS_TEMPLATE:
9827 /* In a type which contains a nested-name-specifier, template
9828 argument values cannot be deduced for template parameters used
9829 within the nested-name-specifier. */
9832 case TEMPLATE_TYPE_PARM:
9833 case TEMPLATE_TEMPLATE_PARM:
9834 case BOUND_TEMPLATE_TEMPLATE_PARM:
9835 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9837 if (TEMPLATE_TYPE_LEVEL (parm)
9838 != template_decl_level (tparm))
9839 /* The PARM is not one we're trying to unify. Just check
9840 to see if it matches ARG. */
9841 return (TREE_CODE (arg) == TREE_CODE (parm)
9842 && same_type_p (parm, arg)) ? 0 : 1;
9843 idx = TEMPLATE_TYPE_IDX (parm);
9844 targ = TREE_VEC_ELT (targs, idx);
9845 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9847 /* Check for mixed types and values. */
9848 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9849 && TREE_CODE (tparm) != TYPE_DECL)
9850 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9851 && TREE_CODE (tparm) != TEMPLATE_DECL))
9854 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9856 /* ARG must be constructed from a template class or a template
9857 template parameter. */
9858 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9859 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9863 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9864 tree parmvec = TYPE_TI_ARGS (parm);
9865 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9867 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9870 /* The parameter and argument roles have to be switched here
9871 in order to handle default arguments properly. For example,
9872 template<template <class> class TT> void f(TT<int>)
9873 should be able to accept vector<int> which comes from
9874 template <class T, class Allocator = allocator>
9877 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9881 /* Deduce arguments T, i from TT<T> or TT<i>.
9882 We check each element of PARMVEC and ARGVEC individually
9883 rather than the whole TREE_VEC since they can have
9884 different number of elements. */
9886 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9888 if (unify (tparms, targs,
9889 TREE_VEC_ELT (parmvec, i),
9890 TREE_VEC_ELT (argvec, i),
9895 arg = TYPE_TI_TEMPLATE (arg);
9897 /* Fall through to deduce template name. */
9900 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9901 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9903 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9905 /* Simple cases: Value already set, does match or doesn't. */
9906 if (targ != NULL_TREE && template_args_equal (targ, arg))
9913 /* If PARM is `const T' and ARG is only `int', we don't have
9914 a match unless we are allowing additional qualification.
9915 If ARG is `const int' and PARM is just `T' that's OK;
9916 that binds `const int' to `T'. */
9917 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
9921 /* Consider the case where ARG is `const volatile int' and
9922 PARM is `const T'. Then, T should be `volatile int'. */
9923 arg = cp_build_qualified_type_real
9924 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
9925 if (arg == error_mark_node)
9928 /* Simple cases: Value already set, does match or doesn't. */
9929 if (targ != NULL_TREE && same_type_p (targ, arg))
9934 /* Make sure that ARG is not a variable-sized array. (Note
9935 that were talking about variable-sized arrays (like
9936 `int[n]'), rather than arrays of unknown size (like
9937 `int[]').) We'll get very confused by such a type since
9938 the bound of the array will not be computable in an
9939 instantiation. Besides, such types are not allowed in
9940 ISO C++, so we can do as we please here. */
9941 if (variably_modified_type_p (arg, NULL_TREE))
9945 TREE_VEC_ELT (targs, idx) = arg;
9948 case TEMPLATE_PARM_INDEX:
9949 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9951 if (TEMPLATE_PARM_LEVEL (parm)
9952 != template_decl_level (tparm))
9953 /* The PARM is not one we're trying to unify. Just check
9954 to see if it matches ARG. */
9955 return !(TREE_CODE (arg) == TREE_CODE (parm)
9956 && cp_tree_equal (parm, arg));
9958 idx = TEMPLATE_PARM_IDX (parm);
9959 targ = TREE_VEC_ELT (targs, idx);
9962 return !cp_tree_equal (targ, arg);
9964 /* [temp.deduct.type] If, in the declaration of a function template
9965 with a non-type template-parameter, the non-type
9966 template-parameter is used in an expression in the function
9967 parameter-list and, if the corresponding template-argument is
9968 deduced, the template-argument type shall match the type of the
9969 template-parameter exactly, except that a template-argument
9970 deduced from an array bound may be of any integral type.
9971 The non-type parameter might use already deduced type parameters. */
9972 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
9973 if (!TREE_TYPE (arg))
9974 /* Template-parameter dependent expression. Just accept it for now.
9975 It will later be processed in convert_template_argument. */
9977 else if (same_type_p (TREE_TYPE (arg), tparm))
9979 else if ((strict & UNIFY_ALLOW_INTEGER)
9980 && (TREE_CODE (tparm) == INTEGER_TYPE
9981 || TREE_CODE (tparm) == BOOLEAN_TYPE))
9982 /* Convert the ARG to the type of PARM; the deduced non-type
9983 template argument must exactly match the types of the
9984 corresponding parameter. */
9985 arg = fold (build_nop (TREE_TYPE (parm), arg));
9986 else if (uses_template_parms (tparm))
9987 /* We haven't deduced the type of this parameter yet. Try again
9993 TREE_VEC_ELT (targs, idx) = arg;
9998 /* A pointer-to-member constant can be unified only with
9999 another constant. */
10000 if (TREE_CODE (arg) != PTRMEM_CST)
10003 /* Just unify the class member. It would be useless (and possibly
10004 wrong, depending on the strict flags) to unify also
10005 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10006 arg refer to the same variable, even if through different
10007 classes. For instance:
10009 struct A { int x; };
10012 Unification of &A::x and &B::x must succeed. */
10013 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10014 PTRMEM_CST_MEMBER (arg), strict);
10019 if (TREE_CODE (arg) != POINTER_TYPE)
10022 /* [temp.deduct.call]
10024 A can be another pointer or pointer to member type that can
10025 be converted to the deduced A via a qualification
10026 conversion (_conv.qual_).
10028 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10029 This will allow for additional cv-qualification of the
10030 pointed-to types if appropriate. */
10032 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10033 /* The derived-to-base conversion only persists through one
10034 level of pointers. */
10035 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10037 return unify (tparms, targs, TREE_TYPE (parm),
10038 TREE_TYPE (arg), strict);
10041 case REFERENCE_TYPE:
10042 if (TREE_CODE (arg) != REFERENCE_TYPE)
10044 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10045 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10048 if (TREE_CODE (arg) != ARRAY_TYPE)
10050 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10051 != (TYPE_DOMAIN (arg) == NULL_TREE))
10053 if (TYPE_DOMAIN (parm) != NULL_TREE)
10058 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10059 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10061 /* Our representation of array types uses "N - 1" as the
10062 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10063 not an integer constant. */
10064 if (TREE_CODE (parm_max) == MINUS_EXPR)
10066 arg_max = fold (build2 (PLUS_EXPR,
10069 TREE_OPERAND (parm_max, 1)));
10070 parm_max = TREE_OPERAND (parm_max, 0);
10073 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10076 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10077 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10084 case ENUMERAL_TYPE:
10086 if (TREE_CODE (arg) != TREE_CODE (parm))
10089 /* We have already checked cv-qualification at the top of the
10091 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10094 /* As far as unification is concerned, this wins. Later checks
10095 will invalidate it if necessary. */
10098 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10099 /* Type INTEGER_CST can come from ordinary constant template args. */
10101 while (TREE_CODE (arg) == NOP_EXPR)
10102 arg = TREE_OPERAND (arg, 0);
10104 if (TREE_CODE (arg) != INTEGER_CST)
10106 return !tree_int_cst_equal (parm, arg);
10111 if (TREE_CODE (arg) != TREE_VEC)
10113 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10115 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10116 if (unify (tparms, targs,
10117 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10125 if (TREE_CODE (arg) != TREE_CODE (parm))
10128 if (TYPE_PTRMEMFUNC_P (parm))
10130 if (!TYPE_PTRMEMFUNC_P (arg))
10133 return unify (tparms, targs,
10134 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10135 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10139 if (CLASSTYPE_TEMPLATE_INFO (parm))
10141 tree t = NULL_TREE;
10143 if (strict_in & UNIFY_ALLOW_DERIVED)
10145 /* First, we try to unify the PARM and ARG directly. */
10146 t = try_class_unification (tparms, targs,
10151 /* Fallback to the special case allowed in
10152 [temp.deduct.call]:
10154 If P is a class, and P has the form
10155 template-id, then A can be a derived class of
10156 the deduced A. Likewise, if P is a pointer to
10157 a class of the form template-id, A can be a
10158 pointer to a derived class pointed to by the
10160 t = get_template_base (tparms, targs, parm, arg);
10166 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10167 && (CLASSTYPE_TI_TEMPLATE (parm)
10168 == CLASSTYPE_TI_TEMPLATE (arg)))
10169 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10170 Then, we should unify `int' and `U'. */
10173 /* There's no chance of unification succeeding. */
10176 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10177 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10179 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10184 case FUNCTION_TYPE:
10185 if (TREE_CODE (arg) != TREE_CODE (parm))
10188 if (unify (tparms, targs, TREE_TYPE (parm),
10189 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10191 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10192 TYPE_ARG_TYPES (arg), 1,
10193 DEDUCE_EXACT, 0, -1);
10196 if (TREE_CODE (arg) != OFFSET_TYPE)
10198 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10199 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10201 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10205 if (DECL_TEMPLATE_PARM_P (parm))
10206 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10207 if (arg != decl_constant_value (parm))
10212 case TEMPLATE_DECL:
10213 /* Matched cases are handled by the ARG == PARM test above. */
10217 gcc_assert (EXPR_P (parm));
10219 /* We must be looking at an expression. This can happen with
10223 void foo(S<I>, S<I + 2>);
10225 This is a "nondeduced context":
10229 The nondeduced contexts are:
10231 --A type that is a template-id in which one or more of
10232 the template-arguments is an expression that references
10233 a template-parameter.
10235 In these cases, we assume deduction succeeded, but don't
10236 actually infer any unifications. */
10238 if (!uses_template_parms (parm)
10239 && !template_args_equal (parm, arg))
10246 /* Note that DECL can be defined in this translation unit, if
10250 mark_definable (tree decl)
10253 DECL_NOT_REALLY_EXTERN (decl) = 1;
10254 FOR_EACH_CLONE (clone, decl)
10255 DECL_NOT_REALLY_EXTERN (clone) = 1;
10258 /* Called if RESULT is explicitly instantiated, or is a member of an
10259 explicitly instantiated class. */
10262 mark_decl_instantiated (tree result, int extern_p)
10264 SET_DECL_EXPLICIT_INSTANTIATION (result);
10266 /* If this entity has already been written out, it's too late to
10267 make any modifications. */
10268 if (TREE_ASM_WRITTEN (result))
10271 if (TREE_CODE (result) != FUNCTION_DECL)
10272 /* The TREE_PUBLIC flag for function declarations will have been
10273 set correctly by tsubst. */
10274 TREE_PUBLIC (result) = 1;
10276 /* This might have been set by an earlier implicit instantiation. */
10277 DECL_COMDAT (result) = 0;
10280 DECL_NOT_REALLY_EXTERN (result) = 0;
10283 mark_definable (result);
10284 /* Always make artificials weak. */
10285 if (DECL_ARTIFICIAL (result) && flag_weak)
10286 comdat_linkage (result);
10287 /* For WIN32 we also want to put explicit instantiations in
10288 linkonce sections. */
10289 else if (TREE_PUBLIC (result))
10290 maybe_make_one_only (result);
10293 /* If EXTERN_P, then this function will not be emitted -- unless
10294 followed by an explicit instantiation, at which point its linkage
10295 will be adjusted. If !EXTERN_P, then this function will be
10296 emitted here. In neither circumstance do we want
10297 import_export_decl to adjust the linkage. */
10298 DECL_INTERFACE_KNOWN (result) = 1;
10301 /* Given two function templates PAT1 and PAT2, return:
10303 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
10305 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10306 -1 if PAT2 is more specialized than PAT1.
10307 0 if neither is more specialized.
10309 LEN is passed through to fn_type_unification. */
10312 more_specialized (tree pat1, tree pat2, int deduce, int len)
10317 /* If template argument deduction succeeds, we substitute the
10318 resulting arguments into non-deduced contexts. While doing that,
10319 we must be aware that we may encounter dependent types. */
10320 ++processing_template_decl;
10321 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
10322 NULL_TREE, 0, deduce, len);
10326 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
10327 NULL_TREE, 0, deduce, len);
10330 --processing_template_decl;
10335 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10337 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10338 -1 if PAT2 is more specialized than PAT1.
10339 0 if neither is more specialized.
10341 FULL_ARGS is the full set of template arguments that triggers this
10342 partial ordering. */
10345 more_specialized_class (tree pat1, tree pat2, tree full_args)
10350 /* Just like what happens for functions, if we are ordering between
10351 different class template specializations, we may encounter dependent
10352 types in the arguments, and we need our dependency check functions
10353 to behave correctly. */
10354 ++processing_template_decl;
10355 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10356 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10360 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10361 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10364 --processing_template_decl;
10369 /* Return the template arguments that will produce the function signature
10370 DECL from the function template FN, with the explicit template
10371 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
10372 also match. Return NULL_TREE if no satisfactory arguments could be
10373 found. DEDUCE and LEN are passed through to fn_type_unification. */
10376 get_bindings_real (tree fn,
10378 tree explicit_args,
10383 int ntparms = DECL_NTPARMS (fn);
10384 tree targs = make_tree_vec (ntparms);
10386 tree decl_arg_types;
10389 /* Substitute the explicit template arguments into the type of DECL.
10390 The call to fn_type_unification will handle substitution into the
10392 decl_type = TREE_TYPE (decl);
10393 if (explicit_args && uses_template_parms (decl_type))
10396 tree converted_args;
10398 if (DECL_TEMPLATE_INFO (decl))
10399 tmpl = DECL_TI_TEMPLATE (decl);
10401 /* We can get here for some invalid specializations. */
10405 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10406 explicit_args, NULL_TREE,
10407 tf_none, /*require_all_arguments=*/0));
10408 if (converted_args == error_mark_node)
10411 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10412 if (decl_type == error_mark_node)
10416 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10417 /* Never do unification on the 'this' parameter. */
10418 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10419 decl_arg_types = TREE_CHAIN (decl_arg_types);
10421 i = fn_type_unification (fn, explicit_args, targs,
10423 (check_rettype || DECL_CONV_FN_P (fn)
10424 ? TREE_TYPE (decl_type) : NULL_TREE),
10433 /* For most uses, we want to check the return type. */
10436 get_bindings (tree fn, tree decl, tree explicit_args)
10438 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10441 /* But for resolve_overloaded_unification, we only care about the parameter
10445 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10447 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10450 /* Return the innermost template arguments that, when applied to a
10451 template specialization whose innermost template parameters are
10452 TPARMS, and whose specialization arguments are PARMS, yield the
10455 For example, suppose we have:
10457 template <class T, class U> struct S {};
10458 template <class T> struct S<T*, int> {};
10460 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10461 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10462 int}. The resulting vector will be {double}, indicating that `T'
10463 is bound to `double'. */
10466 get_class_bindings (tree tparms, tree parms, tree args)
10468 int i, ntparms = TREE_VEC_LENGTH (tparms);
10469 tree vec = make_tree_vec (ntparms);
10471 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10475 for (i = 0; i < ntparms; ++i)
10476 if (! TREE_VEC_ELT (vec, i))
10479 if (verify_class_unification (vec, parms, args))
10485 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10486 Pick the most specialized template, and return the corresponding
10487 instantiation, or if there is no corresponding instantiation, the
10488 template itself. If there is no most specialized template,
10489 error_mark_node is returned. If there are no templates at all,
10490 NULL_TREE is returned. */
10493 most_specialized_instantiation (tree instantiations)
10498 if (!instantiations)
10501 champ = instantiations;
10502 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10504 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10512 fn = TREE_CHAIN (fn);
10514 return error_mark_node;
10520 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10522 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10525 return error_mark_node;
10528 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10531 /* Return the most specialized of the list of templates in FNS that can
10532 produce an instantiation matching DECL, given the explicit template
10533 arguments EXPLICIT_ARGS. */
10536 most_specialized (tree fns, tree decl, tree explicit_args)
10538 tree candidates = NULL_TREE;
10541 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10543 tree candidate = TREE_VALUE (fn);
10545 args = get_bindings (candidate, decl, explicit_args);
10547 candidates = tree_cons (NULL_TREE, candidate, candidates);
10550 return most_specialized_instantiation (candidates);
10553 /* If DECL is a specialization of some template, return the most
10554 general such template. Otherwise, returns NULL_TREE.
10556 For example, given:
10558 template <class T> struct S { template <class U> void f(U); };
10560 if TMPL is `template <class U> void S<int>::f(U)' this will return
10561 the full template. This function will not trace past partial
10562 specializations, however. For example, given in addition:
10564 template <class T> struct S<T*> { template <class U> void f(U); };
10566 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10567 `template <class T> template <class U> S<T*>::f(U)'. */
10570 most_general_template (tree decl)
10572 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10573 an immediate specialization. */
10574 if (TREE_CODE (decl) == FUNCTION_DECL)
10576 if (DECL_TEMPLATE_INFO (decl)) {
10577 decl = DECL_TI_TEMPLATE (decl);
10579 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10580 template friend. */
10581 if (TREE_CODE (decl) != TEMPLATE_DECL)
10587 /* Look for more and more general templates. */
10588 while (DECL_TEMPLATE_INFO (decl))
10590 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10591 (See cp-tree.h for details.) */
10592 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10595 if (CLASS_TYPE_P (TREE_TYPE (decl))
10596 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10599 /* Stop if we run into an explicitly specialized class template. */
10600 if (!DECL_NAMESPACE_SCOPE_P (decl)
10601 && DECL_CONTEXT (decl)
10602 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10605 decl = DECL_TI_TEMPLATE (decl);
10611 /* Return the most specialized of the class template specializations
10612 of TMPL which can produce an instantiation matching ARGS, or
10613 error_mark_node if the choice is ambiguous. */
10616 most_specialized_class (tree tmpl, tree args)
10618 tree list = NULL_TREE;
10623 tmpl = most_general_template (tmpl);
10624 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10627 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10630 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10631 TREE_TYPE (list) = TREE_TYPE (t);
10640 t = TREE_CHAIN (t);
10641 for (; t; t = TREE_CHAIN (t))
10643 fate = more_specialized_class (champ, t, args);
10650 t = TREE_CHAIN (t);
10652 return error_mark_node;
10658 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10660 fate = more_specialized_class (champ, t, args);
10662 return error_mark_node;
10668 /* Explicitly instantiate DECL. */
10671 do_decl_instantiation (tree decl, tree storage)
10673 tree result = NULL_TREE;
10677 /* An error occurred, for which grokdeclarator has already issued
10678 an appropriate message. */
10680 else if (! DECL_LANG_SPECIFIC (decl))
10682 error ("explicit instantiation of non-template %q#D", decl);
10685 else if (TREE_CODE (decl) == VAR_DECL)
10687 /* There is an asymmetry here in the way VAR_DECLs and
10688 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10689 the latter, the DECL we get back will be marked as a
10690 template instantiation, and the appropriate
10691 DECL_TEMPLATE_INFO will be set up. This does not happen for
10692 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10693 should handle VAR_DECLs as it currently handles
10695 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10696 if (!result || TREE_CODE (result) != VAR_DECL)
10698 error ("no matching template for %qD found", decl);
10702 else if (TREE_CODE (decl) != FUNCTION_DECL)
10704 error ("explicit instantiation of %q#D", decl);
10710 /* Check for various error cases. Note that if the explicit
10711 instantiation is valid the RESULT will currently be marked as an
10712 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10713 until we get here. */
10715 if (DECL_TEMPLATE_SPECIALIZATION (result))
10717 /* DR 259 [temp.spec].
10719 Both an explicit instantiation and a declaration of an explicit
10720 specialization shall not appear in a program unless the explicit
10721 instantiation follows a declaration of the explicit specialization.
10723 For a given set of template parameters, if an explicit
10724 instantiation of a template appears after a declaration of an
10725 explicit specialization for that template, the explicit
10726 instantiation has no effect. */
10729 else if (DECL_EXPLICIT_INSTANTIATION (result))
10733 No program shall explicitly instantiate any template more
10736 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10737 the first instantiation was `extern' and the second is not,
10738 and EXTERN_P for the opposite case. */
10739 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10740 pedwarn ("duplicate explicit instantiation of %q#D", result);
10741 /* If an "extern" explicit instantiation follows an ordinary
10742 explicit instantiation, the template is instantiated. */
10746 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10748 error ("no matching template for %qD found", result);
10751 else if (!DECL_TEMPLATE_INFO (result))
10753 pedwarn ("explicit instantiation of non-template %q#D", result);
10757 if (storage == NULL_TREE)
10759 else if (storage == ridpointers[(int) RID_EXTERN])
10761 if (pedantic && !in_system_header)
10762 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
10767 error ("storage class %qD applied to template instantiation", storage);
10769 mark_decl_instantiated (result, extern_p);
10771 instantiate_decl (result, /*defer_ok=*/1, /*undefined_ok=*/0);
10775 mark_class_instantiated (tree t, int extern_p)
10777 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10778 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10779 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10780 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10783 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10784 rest_of_type_compilation (t, 1);
10788 /* Called from do_type_instantiation through binding_table_foreach to
10789 do recursive instantiation for the type bound in ENTRY. */
10791 bt_instantiate_type_proc (binding_entry entry, void *data)
10793 tree storage = *(tree *) data;
10795 if (IS_AGGR_TYPE (entry->type)
10796 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10797 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10800 /* Called from do_type_instantiation to instantiate a member
10801 (a member function or a static member variable) of an
10802 explicitly instantiated class template. */
10804 instantiate_class_member (tree decl, int extern_p)
10806 mark_decl_instantiated (decl, extern_p);
10808 instantiate_decl (decl, /*defer_ok=*/1, /* undefined_ok=*/1);
10811 /* Perform an explicit instantiation of template class T. STORAGE, if
10812 non-null, is the RID for extern, inline or static. COMPLAIN is
10813 nonzero if this is called from the parser, zero if called recursively,
10814 since the standard is unclear (as detailed below). */
10817 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10822 int previous_instantiation_extern_p = 0;
10824 if (TREE_CODE (t) == TYPE_DECL)
10827 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10829 error ("explicit instantiation of non-template type %qT", t);
10835 if (!COMPLETE_TYPE_P (t))
10837 if (complain & tf_error)
10838 error ("explicit instantiation of %q#T before definition of template",
10843 if (storage != NULL_TREE)
10845 if (pedantic && !in_system_header)
10846 pedwarn("ISO C++ forbids the use of `%E' on explicit instantiations",
10849 if (storage == ridpointers[(int) RID_INLINE])
10851 else if (storage == ridpointers[(int) RID_EXTERN])
10853 else if (storage == ridpointers[(int) RID_STATIC])
10857 error ("storage class %qD applied to template instantiation",
10863 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10865 /* DR 259 [temp.spec].
10867 Both an explicit instantiation and a declaration of an explicit
10868 specialization shall not appear in a program unless the explicit
10869 instantiation follows a declaration of the explicit specialization.
10871 For a given set of template parameters, if an explicit
10872 instantiation of a template appears after a declaration of an
10873 explicit specialization for that template, the explicit
10874 instantiation has no effect. */
10877 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10881 No program shall explicitly instantiate any template more
10884 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
10885 instantiation was `extern'. If EXTERN_P then the second is.
10886 These cases are OK. */
10887 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
10889 if (!previous_instantiation_extern_p && !extern_p
10890 && (complain & tf_error))
10891 pedwarn ("duplicate explicit instantiation of %q#T", t);
10893 /* If we've already instantiated the template, just return now. */
10894 if (!CLASSTYPE_INTERFACE_ONLY (t))
10898 mark_class_instantiated (t, extern_p);
10906 /* In contrast to implicit instantiation, where only the
10907 declarations, and not the definitions, of members are
10908 instantiated, we have here:
10912 The explicit instantiation of a class template specialization
10913 implies the instantiation of all of its members not
10914 previously explicitly specialized in the translation unit
10915 containing the explicit instantiation.
10917 Of course, we can't instantiate member template classes, since
10918 we don't have any arguments for them. Note that the standard
10919 is unclear on whether the instantiation of the members are
10920 *explicit* instantiations or not. However, the most natural
10921 interpretation is that it should be an explicit instantiation. */
10924 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
10925 if (TREE_CODE (tmp) == FUNCTION_DECL
10926 && DECL_TEMPLATE_INSTANTIATION (tmp))
10927 instantiate_class_member (tmp, extern_p);
10929 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
10930 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
10931 instantiate_class_member (tmp, extern_p);
10933 if (CLASSTYPE_NESTED_UTDS (t))
10934 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
10935 bt_instantiate_type_proc, &storage);
10939 /* Given a function DECL, which is a specialization of TMPL, modify
10940 DECL to be a re-instantiation of TMPL with the same template
10941 arguments. TMPL should be the template into which tsubst'ing
10942 should occur for DECL, not the most general template.
10944 One reason for doing this is a scenario like this:
10947 void f(const T&, int i);
10949 void g() { f(3, 7); }
10952 void f(const T& t, const int i) { }
10954 Note that when the template is first instantiated, with
10955 instantiate_template, the resulting DECL will have no name for the
10956 first parameter, and the wrong type for the second. So, when we go
10957 to instantiate the DECL, we regenerate it. */
10960 regenerate_decl_from_template (tree decl, tree tmpl)
10962 /* The arguments used to instantiate DECL, from the most general
10967 args = DECL_TI_ARGS (decl);
10968 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
10970 /* Make sure that we can see identifiers, and compute access
10972 push_access_scope (decl);
10974 if (TREE_CODE (decl) == FUNCTION_DECL)
10982 args_depth = TMPL_ARGS_DEPTH (args);
10983 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
10984 if (args_depth > parms_depth)
10985 args = get_innermost_template_args (args, parms_depth);
10987 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
10988 args, tf_error, NULL_TREE);
10990 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
10993 /* Merge parameter declarations. */
10994 decl_parm = skip_artificial_parms_for (decl,
10995 DECL_ARGUMENTS (decl));
10997 = skip_artificial_parms_for (code_pattern,
10998 DECL_ARGUMENTS (code_pattern));
11003 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11004 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11005 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11007 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11008 TREE_TYPE (decl_parm) = parm_type;
11009 decl_parm = TREE_CHAIN (decl_parm);
11010 pattern_parm = TREE_CHAIN (pattern_parm);
11013 /* Merge additional specifiers from the CODE_PATTERN. */
11014 if (DECL_DECLARED_INLINE_P (code_pattern)
11015 && !DECL_DECLARED_INLINE_P (decl))
11016 DECL_DECLARED_INLINE_P (decl) = 1;
11017 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11018 DECL_INLINE (decl) = 1;
11020 else if (TREE_CODE (decl) == VAR_DECL)
11022 if (!DECL_INITIALIZED_IN_CLASS_P (decl)
11023 && DECL_INITIAL (code_pattern))
11024 DECL_INITIAL (decl) =
11025 tsubst_expr (DECL_INITIAL (code_pattern), args,
11026 tf_error, DECL_TI_TEMPLATE (decl));
11029 gcc_unreachable ();
11031 pop_access_scope (decl);
11034 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11035 substituted to get DECL. */
11038 template_for_substitution (tree decl)
11040 tree tmpl = DECL_TI_TEMPLATE (decl);
11042 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11043 for the instantiation. This is not always the most general
11044 template. Consider, for example:
11047 struct S { template <class U> void f();
11048 template <> void f<int>(); };
11050 and an instantiation of S<double>::f<int>. We want TD to be the
11051 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11052 while (/* An instantiation cannot have a definition, so we need a
11053 more general template. */
11054 DECL_TEMPLATE_INSTANTIATION (tmpl)
11055 /* We must also deal with friend templates. Given:
11057 template <class T> struct S {
11058 template <class U> friend void f() {};
11061 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11062 so far as the language is concerned, but that's still
11063 where we get the pattern for the instantiation from. On
11064 other hand, if the definition comes outside the class, say:
11066 template <class T> struct S {
11067 template <class U> friend void f();
11069 template <class U> friend void f() {}
11071 we don't need to look any further. That's what the check for
11072 DECL_INITIAL is for. */
11073 || (TREE_CODE (decl) == FUNCTION_DECL
11074 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11075 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11077 /* The present template, TD, should not be a definition. If it
11078 were a definition, we should be using it! Note that we
11079 cannot restructure the loop to just keep going until we find
11080 a template with a definition, since that might go too far if
11081 a specialization was declared, but not defined. */
11082 gcc_assert (TREE_CODE (decl) != VAR_DECL
11083 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11085 /* Fetch the more general template. */
11086 tmpl = DECL_TI_TEMPLATE (tmpl);
11092 /* Produce the definition of D, a _DECL generated from a template. If
11093 DEFER_OK is nonzero, then we don't have to actually do the
11094 instantiation now; we just have to do it sometime. Normally it is
11095 an error if this is an explicit instantiation but D is undefined.
11096 If UNDEFINED_OK is nonzero, then instead we treat it as an implicit
11097 instantiation. UNDEFINED_OK is nonzero only if we are being used
11098 to instantiate the members of an explicitly instantiated class
11103 instantiate_decl (tree d, int defer_ok, int undefined_ok)
11105 tree tmpl = DECL_TI_TEMPLATE (d);
11112 int pattern_defined;
11114 location_t saved_loc = input_location;
11116 /* This function should only be used to instantiate templates for
11117 functions and static member variables. */
11118 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11119 || TREE_CODE (d) == VAR_DECL);
11121 /* Variables are never deferred; if instantiation is required, they
11122 are instantiated right away. That allows for better code in the
11123 case that an expression refers to the value of the variable --
11124 if the variable has a constant value the referring expression can
11125 take advantage of that fact. */
11126 if (TREE_CODE (d) == VAR_DECL)
11129 /* Don't instantiate cloned functions. Instead, instantiate the
11130 functions they cloned. */
11131 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11132 d = DECL_CLONED_FUNCTION (d);
11134 if (DECL_TEMPLATE_INSTANTIATED (d))
11135 /* D has already been instantiated. It might seem reasonable to
11136 check whether or not D is an explicit instantiation, and, if so,
11137 stop here. But when an explicit instantiation is deferred
11138 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11139 is set, even though we still need to do the instantiation. */
11142 /* If we already have a specialization of this declaration, then
11143 there's no reason to instantiate it. Note that
11144 retrieve_specialization gives us both instantiations and
11145 specializations, so we must explicitly check
11146 DECL_TEMPLATE_SPECIALIZATION. */
11147 gen_tmpl = most_general_template (tmpl);
11148 gen_args = DECL_TI_ARGS (d);
11149 spec = retrieve_specialization (gen_tmpl, gen_args,
11150 /*class_specializations_p=*/false);
11151 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11154 /* This needs to happen before any tsubsting. */
11155 if (! push_tinst_level (d))
11158 timevar_push (TV_PARSE);
11160 /* We may be in the middle of deferred access check. Disable it now. */
11161 push_deferring_access_checks (dk_no_deferred);
11163 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11164 for the instantiation. */
11165 td = template_for_substitution (d);
11166 code_pattern = DECL_TEMPLATE_RESULT (td);
11168 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11169 || DECL_TEMPLATE_SPECIALIZATION (td))
11170 /* In the case of a friend template whose definition is provided
11171 outside the class, we may have too many arguments. Drop the
11172 ones we don't need. The same is true for specializations. */
11173 args = get_innermost_template_args
11174 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11178 if (TREE_CODE (d) == FUNCTION_DECL)
11179 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11181 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11182 /* Unless an explicit instantiation directive has already determined
11183 the linkage of D, remember that a definition is available for
11185 if (pattern_defined
11186 && !DECL_INTERFACE_KNOWN (d)
11187 && !DECL_NOT_REALLY_EXTERN (d))
11188 mark_definable (d);
11190 input_location = DECL_SOURCE_LOCATION (d);
11192 if (! pattern_defined && DECL_EXPLICIT_INSTANTIATION (d) && undefined_ok)
11194 DECL_NOT_REALLY_EXTERN (d) = 0;
11195 SET_DECL_IMPLICIT_INSTANTIATION (d);
11200 /* Recheck the substitutions to obtain any warning messages
11201 about ignoring cv qualifiers. */
11202 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11203 tree type = TREE_TYPE (gen);
11205 /* Make sure that we can see identifiers, and compute access
11206 correctly. D is already the target FUNCTION_DECL with the
11208 push_access_scope (d);
11210 if (TREE_CODE (gen) == FUNCTION_DECL)
11212 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11213 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11214 tf_error | tf_warning, d);
11215 /* Don't simply tsubst the function type, as that will give
11216 duplicate warnings about poor parameter qualifications.
11217 The function arguments are the same as the decl_arguments
11218 without the top level cv qualifiers. */
11219 type = TREE_TYPE (type);
11221 tsubst (type, gen_args, tf_error | tf_warning, d);
11223 pop_access_scope (d);
11226 /* We should have set up DECL_INITIAL in instantiate_class_template
11227 for in-class definitions of static data members. */
11228 gcc_assert (!(TREE_CODE (d) == VAR_DECL
11229 && DECL_INITIALIZED_IN_CLASS_P (d)
11230 && DECL_INITIAL (d) == NULL_TREE));
11232 /* Do not instantiate templates that we know will be defined
11234 if (DECL_INTERFACE_KNOWN (d)
11235 && DECL_REALLY_EXTERN (d)
11236 && ! (TREE_CODE (d) == FUNCTION_DECL
11237 && DECL_INLINE (d)))
11239 /* Defer all other templates, unless we have been explicitly
11240 forbidden from doing so. We restore the source position here
11241 because it's used by add_pending_template. */
11242 else if (! pattern_defined || defer_ok)
11244 input_location = saved_loc;
11246 if (at_eof && !pattern_defined
11247 && DECL_EXPLICIT_INSTANTIATION (d))
11250 The definition of a non-exported function template, a
11251 non-exported member function template, or a non-exported
11252 member function or static data member of a class template
11253 shall be present in every translation unit in which it is
11254 explicitly instantiated. */
11256 ("explicit instantiation of %qD but no definition available", d);
11258 add_pending_template (d);
11261 /* Tell the repository that D is available in this translation unit
11262 -- and see if it is supposed to be instantiated here. */
11263 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11265 /* In a PCH file, despite the fact that the repository hasn't
11266 requested instantiation in the PCH it is still possible that
11267 an instantiation will be required in a file that includes the
11270 add_pending_template (d);
11271 /* Instantiate inline functions so that the inliner can do its
11272 job, even though we'll not be emitting a copy of this
11274 if (!(TREE_CODE (d) == FUNCTION_DECL
11275 && flag_inline_trees
11276 && DECL_DECLARED_INLINE_P (d)))
11280 need_push = !cfun || !global_bindings_p ();
11282 push_to_top_level ();
11284 /* Mark D as instantiated so that recursive calls to
11285 instantiate_decl do not try to instantiate it again. */
11286 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11288 /* Regenerate the declaration in case the template has been modified
11289 by a subsequent redeclaration. */
11290 regenerate_decl_from_template (d, td);
11292 /* We already set the file and line above. Reset them now in case
11293 they changed as a result of calling regenerate_decl_from_template. */
11294 input_location = DECL_SOURCE_LOCATION (d);
11296 if (TREE_CODE (d) == VAR_DECL)
11298 /* Clear out DECL_RTL; whatever was there before may not be right
11299 since we've reset the type of the declaration. */
11300 SET_DECL_RTL (d, NULL_RTX);
11301 DECL_IN_AGGR_P (d) = 0;
11303 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11304 initializer. That function will defer actual emission until
11305 we have a chance to determine linkage. */
11306 DECL_EXTERNAL (d) = 0;
11308 /* Enter the scope of D so that access-checking works correctly. */
11309 push_nested_class (DECL_CONTEXT (d));
11311 (!DECL_INITIALIZED_IN_CLASS_P (d)
11312 ? DECL_INITIAL (d) : NULL_TREE),
11314 pop_nested_class ();
11316 else if (TREE_CODE (d) == FUNCTION_DECL)
11318 htab_t saved_local_specializations;
11323 /* Save away the current list, in case we are instantiating one
11324 template from within the body of another. */
11325 saved_local_specializations = local_specializations;
11327 /* Set up the list of local specializations. */
11328 local_specializations = htab_create (37,
11329 hash_local_specialization,
11330 eq_local_specializations,
11333 /* Set up context. */
11334 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11336 /* Create substitution entries for the parameters. */
11337 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11338 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11339 spec_parm = DECL_ARGUMENTS (d);
11340 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11342 register_local_specialization (spec_parm, tmpl_parm);
11343 spec_parm = skip_artificial_parms_for (d, spec_parm);
11344 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11348 register_local_specialization (spec_parm, tmpl_parm);
11349 tmpl_parm = TREE_CHAIN (tmpl_parm);
11350 spec_parm = TREE_CHAIN (spec_parm);
11352 gcc_assert (!spec_parm);
11354 /* Substitute into the body of the function. */
11355 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11356 tf_error | tf_warning, tmpl);
11358 /* We don't need the local specializations any more. */
11359 htab_delete (local_specializations);
11360 local_specializations = saved_local_specializations;
11362 /* Finish the function. */
11363 d = finish_function (0);
11364 expand_or_defer_fn (d);
11367 /* We're not deferring instantiation any more. */
11368 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11371 pop_from_top_level ();
11374 input_location = saved_loc;
11375 pop_deferring_access_checks ();
11376 pop_tinst_level ();
11378 timevar_pop (TV_PARSE);
11383 /* Run through the list of templates that we wish we could
11384 instantiate, and instantiate any we can. RETRIES is the
11385 number of times we retry pending template instantiation. */
11388 instantiate_pending_templates (int retries)
11391 tree last = NULL_TREE;
11393 location_t saved_loc = input_location;
11395 /* Instantiating templates may trigger vtable generation. This in turn
11396 may require further template instantiations. We place a limit here
11397 to avoid infinite loop. */
11398 if (pending_templates && retries >= max_tinst_depth)
11400 cp_error_at ("template instantiation depth exceeds maximum of %d"
11401 " (use -ftemplate-depth-NN to increase the maximum)"
11402 " instantiating %q+D, possibly from virtual table"
11404 max_tinst_depth, TREE_VALUE (pending_templates));
11412 t = &pending_templates;
11415 tree instantiation = TREE_VALUE (*t);
11417 reopen_tinst_level (TREE_PURPOSE (*t));
11419 if (TYPE_P (instantiation))
11423 if (!COMPLETE_TYPE_P (instantiation))
11425 instantiate_class_template (instantiation);
11426 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11427 for (fn = TYPE_METHODS (instantiation);
11429 fn = TREE_CHAIN (fn))
11430 if (! DECL_ARTIFICIAL (fn))
11431 instantiate_decl (fn, /*defer_ok=*/0,
11432 /*undefined_ok=*/0);
11433 if (COMPLETE_TYPE_P (instantiation))
11437 if (COMPLETE_TYPE_P (instantiation))
11438 /* If INSTANTIATION has been instantiated, then we don't
11439 need to consider it again in the future. */
11440 *t = TREE_CHAIN (*t);
11444 t = &TREE_CHAIN (*t);
11449 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11450 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11452 instantiation = instantiate_decl (instantiation,
11454 /*undefined_ok=*/0);
11455 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11459 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11460 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11461 /* If INSTANTIATION has been instantiated, then we don't
11462 need to consider it again in the future. */
11463 *t = TREE_CHAIN (*t);
11467 t = &TREE_CHAIN (*t);
11471 current_tinst_level = NULL_TREE;
11473 last_pending_template = last;
11475 while (reconsider);
11477 input_location = saved_loc;
11480 /* Substitute ARGVEC into T, which is a list of initializers for
11481 either base class or a non-static data member. The TREE_PURPOSEs
11482 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11483 instantiate_decl. */
11486 tsubst_initializer_list (tree t, tree argvec)
11488 tree inits = NULL_TREE;
11490 for (; t; t = TREE_CHAIN (t))
11496 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11498 decl = expand_member_init (decl);
11499 if (decl && !DECL_P (decl))
11500 in_base_initializer = 1;
11502 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11506 else if (TREE_CODE (init) == TREE_LIST)
11507 for (val = init; val; val = TREE_CHAIN (val))
11508 TREE_VALUE (val) = convert_from_reference (TREE_VALUE (val));
11509 else if (init != void_type_node)
11510 init = convert_from_reference (init);
11512 in_base_initializer = 0;
11516 init = build_tree_list (decl, init);
11517 TREE_CHAIN (init) = inits;
11524 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11527 set_current_access_from_decl (tree decl)
11529 if (TREE_PRIVATE (decl))
11530 current_access_specifier = access_private_node;
11531 else if (TREE_PROTECTED (decl))
11532 current_access_specifier = access_protected_node;
11534 current_access_specifier = access_public_node;
11537 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11538 is the instantiation (which should have been created with
11539 start_enum) and ARGS are the template arguments to use. */
11542 tsubst_enum (tree tag, tree newtag, tree args)
11546 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11551 decl = TREE_VALUE (e);
11552 /* Note that in a template enum, the TREE_VALUE is the
11553 CONST_DECL, not the corresponding INTEGER_CST. */
11554 value = tsubst_expr (DECL_INITIAL (decl),
11555 args, tf_error | tf_warning,
11558 /* Give this enumeration constant the correct access. */
11559 set_current_access_from_decl (decl);
11561 /* Actually build the enumerator itself. */
11562 build_enumerator (DECL_NAME (decl), value, newtag);
11565 finish_enum (newtag);
11566 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11567 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11570 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11571 its type -- but without substituting the innermost set of template
11572 arguments. So, innermost set of template parameters will appear in
11576 get_mostly_instantiated_function_type (tree decl)
11584 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11585 targs = DECL_TI_ARGS (decl);
11586 tparms = DECL_TEMPLATE_PARMS (tmpl);
11587 parm_depth = TMPL_PARMS_DEPTH (tparms);
11589 /* There should be as many levels of arguments as there are levels
11591 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11593 fn_type = TREE_TYPE (tmpl);
11595 if (parm_depth == 1)
11596 /* No substitution is necessary. */
11603 /* Replace the innermost level of the TARGS with NULL_TREEs to
11604 let tsubst know not to substitute for those parameters. */
11605 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11606 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11607 SET_TMPL_ARGS_LEVEL (partial_args, i,
11608 TMPL_ARGS_LEVEL (targs, i));
11609 SET_TMPL_ARGS_LEVEL (partial_args,
11610 TMPL_ARGS_DEPTH (targs),
11611 make_tree_vec (DECL_NTPARMS (tmpl)));
11613 /* Make sure that we can see identifiers, and compute access
11614 correctly. We can just use the context of DECL for the
11615 partial substitution here. It depends only on outer template
11616 parameters, regardless of whether the innermost level is
11617 specialized or not. */
11618 push_access_scope (decl);
11620 ++processing_template_decl;
11621 /* Now, do the (partial) substitution to figure out the
11622 appropriate function type. */
11623 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11624 --processing_template_decl;
11626 /* Substitute into the template parameters to obtain the real
11627 innermost set of parameters. This step is important if the
11628 innermost set of template parameters contains value
11629 parameters whose types depend on outer template parameters. */
11630 TREE_VEC_LENGTH (partial_args)--;
11631 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11633 pop_access_scope (decl);
11639 /* Return truthvalue if we're processing a template different from
11640 the last one involved in diagnostics. */
11642 problematic_instantiation_changed (void)
11644 return last_template_error_tick != tinst_level_tick;
11647 /* Remember current template involved in diagnostics. */
11649 record_last_problematic_instantiation (void)
11651 last_template_error_tick = tinst_level_tick;
11655 current_instantiation (void)
11657 return current_tinst_level;
11660 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11661 type. Return zero for ok, nonzero for disallowed. Issue error and
11662 warning messages under control of COMPLAIN. */
11665 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11667 if (INTEGRAL_TYPE_P (type))
11669 else if (POINTER_TYPE_P (type))
11671 else if (TYPE_PTR_TO_MEMBER_P (type))
11673 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11675 else if (TREE_CODE (type) == TYPENAME_TYPE)
11678 if (complain & tf_error)
11679 error ("%q#T is not a valid type for a template constant parameter", type);
11683 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11684 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11687 dependent_type_p_r (tree type)
11693 A type is dependent if it is:
11695 -- a template parameter. Template template parameters are types
11696 for us (since TYPE_P holds true for them) so we handle
11698 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11699 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11701 /* -- a qualified-id with a nested-name-specifier which contains a
11702 class-name that names a dependent type or whose unqualified-id
11703 names a dependent type. */
11704 if (TREE_CODE (type) == TYPENAME_TYPE)
11706 /* -- a cv-qualified type where the cv-unqualified type is
11708 type = TYPE_MAIN_VARIANT (type);
11709 /* -- a compound type constructed from any dependent type. */
11710 if (TYPE_PTR_TO_MEMBER_P (type))
11711 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11712 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11714 else if (TREE_CODE (type) == POINTER_TYPE
11715 || TREE_CODE (type) == REFERENCE_TYPE)
11716 return dependent_type_p (TREE_TYPE (type));
11717 else if (TREE_CODE (type) == FUNCTION_TYPE
11718 || TREE_CODE (type) == METHOD_TYPE)
11722 if (dependent_type_p (TREE_TYPE (type)))
11724 for (arg_type = TYPE_ARG_TYPES (type);
11726 arg_type = TREE_CHAIN (arg_type))
11727 if (dependent_type_p (TREE_VALUE (arg_type)))
11731 /* -- an array type constructed from any dependent type or whose
11732 size is specified by a constant expression that is
11733 value-dependent. */
11734 if (TREE_CODE (type) == ARRAY_TYPE)
11736 if (TYPE_DOMAIN (type)
11737 && ((value_dependent_expression_p
11738 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11739 || (type_dependent_expression_p
11740 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11742 return dependent_type_p (TREE_TYPE (type));
11745 /* -- a template-id in which either the template name is a template
11747 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11749 /* ... or any of the template arguments is a dependent type or
11750 an expression that is type-dependent or value-dependent. */
11751 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11752 && (any_dependent_template_arguments_p
11753 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11756 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11757 expression is not type-dependent, then it should already been
11759 if (TREE_CODE (type) == TYPEOF_TYPE)
11762 /* The standard does not specifically mention types that are local
11763 to template functions or local classes, but they should be
11764 considered dependent too. For example:
11766 template <int I> void f() {
11771 The size of `E' cannot be known until the value of `I' has been
11772 determined. Therefore, `E' must be considered dependent. */
11773 scope = TYPE_CONTEXT (type);
11774 if (scope && TYPE_P (scope))
11775 return dependent_type_p (scope);
11776 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11777 return type_dependent_expression_p (scope);
11779 /* Other types are non-dependent. */
11783 /* Returns TRUE if TYPE is dependent, in the sense of
11784 [temp.dep.type]. */
11787 dependent_type_p (tree type)
11789 /* If there are no template parameters in scope, then there can't be
11790 any dependent types. */
11791 if (!processing_template_decl)
11794 /* If the type is NULL, we have not computed a type for the entity
11795 in question; in that case, the type is dependent. */
11799 /* Erroneous types can be considered non-dependent. */
11800 if (type == error_mark_node)
11803 /* If we have not already computed the appropriate value for TYPE,
11805 if (!TYPE_DEPENDENT_P_VALID (type))
11807 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11808 TYPE_DEPENDENT_P_VALID (type) = 1;
11811 return TYPE_DEPENDENT_P (type);
11814 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11817 dependent_scope_ref_p (tree expression, bool criterion (tree))
11822 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
11824 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11827 scope = TREE_OPERAND (expression, 0);
11828 name = TREE_OPERAND (expression, 1);
11832 An id-expression is type-dependent if it contains a
11833 nested-name-specifier that contains a class-name that names a
11835 /* The suggested resolution to Core Issue 2 implies that if the
11836 qualifying type is the current class, then we must peek
11839 && currently_open_class (scope)
11840 && !criterion (name))
11842 if (dependent_type_p (scope))
11848 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11849 [temp.dep.constexpr] */
11852 value_dependent_expression_p (tree expression)
11854 if (!processing_template_decl)
11857 /* A name declared with a dependent type. */
11858 if (TREE_CODE (expression) == IDENTIFIER_NODE
11859 || (DECL_P (expression)
11860 && type_dependent_expression_p (expression)))
11862 /* A non-type template parameter. */
11863 if ((TREE_CODE (expression) == CONST_DECL
11864 && DECL_TEMPLATE_PARM_P (expression))
11865 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11867 /* A constant with integral or enumeration type and is initialized
11868 with an expression that is value-dependent. */
11869 if (TREE_CODE (expression) == VAR_DECL
11870 && DECL_INITIAL (expression)
11871 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11872 && value_dependent_expression_p (DECL_INITIAL (expression)))
11874 /* These expressions are value-dependent if the type to which the
11875 cast occurs is dependent or the expression being casted is
11876 value-dependent. */
11877 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11878 || TREE_CODE (expression) == STATIC_CAST_EXPR
11879 || TREE_CODE (expression) == CONST_CAST_EXPR
11880 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11881 || TREE_CODE (expression) == CAST_EXPR)
11883 tree type = TREE_TYPE (expression);
11884 if (dependent_type_p (type))
11886 /* A functional cast has a list of operands. */
11887 expression = TREE_OPERAND (expression, 0);
11890 /* If there are no operands, it must be an expression such
11891 as "int()". This should not happen for aggregate types
11892 because it would form non-constant expressions. */
11893 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
11897 if (TREE_CODE (expression) == TREE_LIST)
11901 if (value_dependent_expression_p (TREE_VALUE (expression)))
11903 expression = TREE_CHAIN (expression);
11905 while (expression);
11909 return value_dependent_expression_p (expression);
11911 /* A `sizeof' expression is value-dependent if the operand is
11913 if (TREE_CODE (expression) == SIZEOF_EXPR
11914 || TREE_CODE (expression) == ALIGNOF_EXPR)
11916 expression = TREE_OPERAND (expression, 0);
11917 if (TYPE_P (expression))
11918 return dependent_type_p (expression);
11919 return type_dependent_expression_p (expression);
11921 if (TREE_CODE (expression) == SCOPE_REF)
11922 return dependent_scope_ref_p (expression, value_dependent_expression_p);
11923 if (TREE_CODE (expression) == COMPONENT_REF)
11924 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
11925 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
11926 /* A constant expression is value-dependent if any subexpression is
11927 value-dependent. */
11928 if (EXPR_P (expression))
11930 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
11933 return (value_dependent_expression_p
11934 (TREE_OPERAND (expression, 0)));
11935 case tcc_comparison:
11937 return ((value_dependent_expression_p
11938 (TREE_OPERAND (expression, 0)))
11939 || (value_dependent_expression_p
11940 (TREE_OPERAND (expression, 1))));
11941 case tcc_expression:
11944 for (i = 0; i < first_rtl_op (TREE_CODE (expression)); ++i)
11945 /* In some cases, some of the operands may be missing.
11946 (For example, in the case of PREDECREMENT_EXPR, the
11947 amount to increment by may be missing.) That doesn't
11948 make the expression dependent. */
11949 if (TREE_OPERAND (expression, i)
11950 && (value_dependent_expression_p
11951 (TREE_OPERAND (expression, i))))
11955 case tcc_reference:
11956 case tcc_statement:
11957 /* These cannot be value dependent. */
11961 gcc_unreachable ();
11965 /* The expression is not value-dependent. */
11969 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11970 [temp.dep.expr]. */
11973 type_dependent_expression_p (tree expression)
11975 if (!processing_template_decl)
11978 if (expression == error_mark_node)
11981 /* An unresolved name is always dependent. */
11982 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11985 /* Some expression forms are never type-dependent. */
11986 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
11987 || TREE_CODE (expression) == SIZEOF_EXPR
11988 || TREE_CODE (expression) == ALIGNOF_EXPR
11989 || TREE_CODE (expression) == TYPEID_EXPR
11990 || TREE_CODE (expression) == DELETE_EXPR
11991 || TREE_CODE (expression) == VEC_DELETE_EXPR
11992 || TREE_CODE (expression) == THROW_EXPR)
11995 /* The types of these expressions depends only on the type to which
11996 the cast occurs. */
11997 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11998 || TREE_CODE (expression) == STATIC_CAST_EXPR
11999 || TREE_CODE (expression) == CONST_CAST_EXPR
12000 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12001 || TREE_CODE (expression) == CAST_EXPR)
12002 return dependent_type_p (TREE_TYPE (expression));
12004 /* The types of these expressions depends only on the type created
12005 by the expression. */
12006 if (TREE_CODE (expression) == NEW_EXPR
12007 || TREE_CODE (expression) == VEC_NEW_EXPR)
12009 /* For NEW_EXPR tree nodes created inside a template, either
12010 the object type itself or a TREE_LIST may appear as the
12012 tree type = TREE_OPERAND (expression, 1);
12013 if (TREE_CODE (type) == TREE_LIST)
12014 /* This is an array type. We need to check array dimensions
12016 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12017 || value_dependent_expression_p
12018 (TREE_OPERAND (TREE_VALUE (type), 1));
12020 return dependent_type_p (type);
12023 if (TREE_CODE (expression) == SCOPE_REF
12024 && dependent_scope_ref_p (expression,
12025 type_dependent_expression_p))
12028 if (TREE_CODE (expression) == FUNCTION_DECL
12029 && DECL_LANG_SPECIFIC (expression)
12030 && DECL_TEMPLATE_INFO (expression)
12031 && (any_dependent_template_arguments_p
12032 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12035 if (TREE_CODE (expression) == TEMPLATE_DECL
12036 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12039 if (TREE_TYPE (expression) == unknown_type_node)
12041 if (TREE_CODE (expression) == ADDR_EXPR)
12042 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12043 if (TREE_CODE (expression) == COMPONENT_REF
12044 || TREE_CODE (expression) == OFFSET_REF)
12046 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12048 expression = TREE_OPERAND (expression, 1);
12049 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12052 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12053 if (TREE_CODE (expression) == SCOPE_REF)
12056 if (TREE_CODE (expression) == BASELINK)
12057 expression = BASELINK_FUNCTIONS (expression);
12059 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12061 if (any_dependent_template_arguments_p
12062 (TREE_OPERAND (expression, 1)))
12064 expression = TREE_OPERAND (expression, 0);
12066 gcc_assert (TREE_CODE (expression) == OVERLOAD);
12070 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12072 expression = OVL_NEXT (expression);
12077 return (dependent_type_p (TREE_TYPE (expression)));
12080 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12081 contains a type-dependent expression. */
12084 any_type_dependent_arguments_p (tree args)
12088 tree arg = TREE_VALUE (args);
12090 if (type_dependent_expression_p (arg))
12092 args = TREE_CHAIN (args);
12097 /* Returns TRUE if the ARG (a template argument) is dependent. */
12100 dependent_template_arg_p (tree arg)
12102 if (!processing_template_decl)
12105 if (TREE_CODE (arg) == TEMPLATE_DECL
12106 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12107 return dependent_template_p (arg);
12108 else if (TYPE_P (arg))
12109 return dependent_type_p (arg);
12111 return (type_dependent_expression_p (arg)
12112 || value_dependent_expression_p (arg));
12115 /* Returns true if ARGS (a collection of template arguments) contains
12116 any dependent arguments. */
12119 any_dependent_template_arguments_p (tree args)
12127 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12129 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12130 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12131 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12138 /* Returns TRUE if the template TMPL is dependent. */
12141 dependent_template_p (tree tmpl)
12143 if (TREE_CODE (tmpl) == OVERLOAD)
12147 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12149 tmpl = OVL_CHAIN (tmpl);
12154 /* Template template parameters are dependent. */
12155 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12156 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12158 /* So are names that have not been looked up. */
12159 if (TREE_CODE (tmpl) == SCOPE_REF
12160 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12162 /* So are member templates of dependent classes. */
12163 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12164 return dependent_type_p (DECL_CONTEXT (tmpl));
12168 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12171 dependent_template_id_p (tree tmpl, tree args)
12173 return (dependent_template_p (tmpl)
12174 || any_dependent_template_arguments_p (args));
12177 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12178 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12179 can be found. Note that this function peers inside uninstantiated
12180 templates and therefore should be used only in extremely limited
12184 resolve_typename_type (tree type, bool only_current_p)
12192 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12194 scope = TYPE_CONTEXT (type);
12195 name = TYPE_IDENTIFIER (type);
12197 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12198 it first before we can figure out what NAME refers to. */
12199 if (TREE_CODE (scope) == TYPENAME_TYPE)
12200 scope = resolve_typename_type (scope, only_current_p);
12201 /* If we don't know what SCOPE refers to, then we cannot resolve the
12203 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12204 return error_mark_node;
12205 /* If the SCOPE is a template type parameter, we have no way of
12206 resolving the name. */
12207 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12209 /* If the SCOPE is not the current instantiation, there's no reason
12210 to look inside it. */
12211 if (only_current_p && !currently_open_class (scope))
12212 return error_mark_node;
12213 /* If SCOPE is a partial instantiation, it will not have a valid
12214 TYPE_FIELDS list, so use the original template. */
12215 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12216 /* Enter the SCOPE so that name lookup will be resolved as if we
12217 were in the class definition. In particular, SCOPE will no
12218 longer be considered a dependent type. */
12219 pop_p = push_scope (scope);
12220 /* Look up the declaration. */
12221 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12222 /* Obtain the set of qualifiers applied to the TYPE. */
12223 quals = cp_type_quals (type);
12224 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12225 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12227 type = error_mark_node;
12228 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12229 && TREE_CODE (decl) == TYPE_DECL)
12230 type = TREE_TYPE (decl);
12231 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12232 && DECL_CLASS_TEMPLATE_P (decl))
12236 /* Obtain the template and the arguments. */
12237 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12238 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12239 /* Instantiate the template. */
12240 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12241 /*entering_scope=*/0, tf_error | tf_user);
12244 type = error_mark_node;
12245 /* Qualify the resulting type. */
12246 if (type != error_mark_node && quals)
12247 type = cp_build_qualified_type (type, quals);
12248 /* Leave the SCOPE. */
12255 /* EXPR is an expression which is not type-dependent. Return a proxy
12256 for EXPR that can be used to compute the types of larger
12257 expressions containing EXPR. */
12260 build_non_dependent_expr (tree expr)
12264 /* Preserve null pointer constants so that the type of things like
12265 "p == 0" where "p" is a pointer can be determined. */
12266 if (null_ptr_cst_p (expr))
12268 /* Preserve OVERLOADs; the functions must be available to resolve
12270 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12271 TREE_OPERAND (expr, 0) : expr);
12272 if (TREE_CODE (inner_expr) == OVERLOAD
12273 || TREE_CODE (inner_expr) == FUNCTION_DECL
12274 || TREE_CODE (inner_expr) == TEMPLATE_DECL
12275 || TREE_CODE (inner_expr) == TEMPLATE_ID_EXPR)
12277 /* Preserve string constants; conversions from string constants to
12278 "char *" are allowed, even though normally a "const char *"
12279 cannot be used to initialize a "char *". */
12280 if (TREE_CODE (expr) == STRING_CST)
12282 /* Preserve arithmetic constants, as an optimization -- there is no
12283 reason to create a new node. */
12284 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12286 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12287 There is at least one place where we want to know that a
12288 particular expression is a throw-expression: when checking a ?:
12289 expression, there are special rules if the second or third
12290 argument is a throw-expression. */
12291 if (TREE_CODE (expr) == THROW_EXPR)
12294 if (TREE_CODE (expr) == COND_EXPR)
12295 return build3 (COND_EXPR,
12297 TREE_OPERAND (expr, 0),
12298 (TREE_OPERAND (expr, 1)
12299 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12300 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12301 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12302 if (TREE_CODE (expr) == COMPOUND_EXPR
12303 && !COMPOUND_EXPR_OVERLOADED (expr))
12304 return build2 (COMPOUND_EXPR,
12306 TREE_OPERAND (expr, 0),
12307 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12309 /* Otherwise, build a NON_DEPENDENT_EXPR.
12311 REFERENCE_TYPEs are not stripped for expressions in templates
12312 because doing so would play havoc with mangling. Consider, for
12315 template <typename T> void f<T& g>() { g(); }
12317 In the body of "f", the expression for "g" will have
12318 REFERENCE_TYPE, even though the standard says that it should
12319 not. The reason is that we must preserve the syntactic form of
12320 the expression so that mangling (say) "f<g>" inside the body of
12321 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12323 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12326 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12327 Return a new TREE_LIST with the various arguments replaced with
12328 equivalent non-dependent expressions. */
12331 build_non_dependent_args (tree args)
12336 new_args = NULL_TREE;
12337 for (a = args; a; a = TREE_CHAIN (a))
12338 new_args = tree_cons (NULL_TREE,
12339 build_non_dependent_expr (TREE_VALUE (a)),
12341 return nreverse (new_args);
12344 #include "gt-cp-pt.h"