1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
38 #include "tree-inline.h"
45 #include "tree-iterator.h"
47 /* The type of functions taking a tree, and some additional data, and
49 typedef int (*tree_fn_t) (tree, void*);
51 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
52 instantiations have been deferred, either because their definitions
53 were not yet available, or because we were putting off doing the work.
54 The TREE_PURPOSE of each entry is either a DECL (for a function or
55 static data member), or a TYPE (for a class) indicating what we are
56 hoping to instantiate. The TREE_VALUE is not used. */
57 static GTY(()) tree pending_templates;
58 static GTY(()) tree last_pending_template;
60 int processing_template_parmlist;
61 static int template_header_count;
63 static GTY(()) tree saved_trees;
64 static GTY(()) varray_type inline_parm_levels;
65 static size_t inline_parm_levels_used;
67 static GTY(()) tree current_tinst_level;
69 static GTY(()) tree saved_access_scope;
71 /* Live only within one (recursive) call to tsubst_expr. We use
72 this to pass the statement expression node from the STMT_EXPR
73 to the EXPR_STMT that is its result. */
74 static tree cur_stmt_expr;
76 /* A map from local variable declarations in the body of the template
77 presently being instantiated to the corresponding instantiated
79 static htab_t local_specializations;
81 #define UNIFY_ALLOW_NONE 0
82 #define UNIFY_ALLOW_MORE_CV_QUAL 1
83 #define UNIFY_ALLOW_LESS_CV_QUAL 2
84 #define UNIFY_ALLOW_DERIVED 4
85 #define UNIFY_ALLOW_INTEGER 8
86 #define UNIFY_ALLOW_OUTER_LEVEL 16
87 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
88 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
89 #define UNIFY_ALLOW_MAX_CORRECTION 128
91 static void push_access_scope (tree);
92 static void pop_access_scope (tree);
93 static int resolve_overloaded_unification (tree, tree, tree, tree,
94 unification_kind_t, int);
95 static int try_one_overload (tree, tree, tree, tree, tree,
96 unification_kind_t, int, bool);
97 static int unify (tree, tree, tree, tree, int);
98 static void add_pending_template (tree);
99 static void reopen_tinst_level (tree);
100 static tree classtype_mangled_name (tree);
101 static char* mangle_class_name_for_template (const char *, tree, tree);
102 static tree tsubst_initializer_list (tree, tree);
103 static tree get_class_bindings (tree, tree, tree);
104 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
105 static void tsubst_enum (tree, tree, tree);
106 static tree add_to_template_args (tree, tree);
107 static tree add_outermost_template_args (tree, tree);
108 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
109 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
110 static int type_unification_real (tree, tree, tree, tree,
111 int, unification_kind_t, int, int);
112 static void note_template_header (int);
113 static tree convert_nontype_argument_function (tree, tree);
114 static tree convert_nontype_argument (tree, tree);
115 static tree convert_template_argument (tree, tree, tree,
116 tsubst_flags_t, int, tree);
117 static tree get_bindings_overload (tree, tree, tree);
118 static int for_each_template_parm (tree, tree_fn_t, void*,
119 struct pointer_set_t*);
120 static tree build_template_parm_index (int, int, int, tree, tree);
121 static int inline_needs_template_parms (tree);
122 static void push_inline_template_parms_recursive (tree, int);
123 static tree retrieve_local_specialization (tree);
124 static void register_local_specialization (tree, tree);
125 static tree reduce_template_parm_level (tree, tree, int);
126 static int mark_template_parm (tree, void *);
127 static int template_parm_this_level_p (tree, void *);
128 static tree tsubst_friend_function (tree, tree);
129 static tree tsubst_friend_class (tree, tree);
130 static int can_complete_type_without_circularity (tree);
131 static tree get_bindings (tree, tree, tree);
132 static tree get_bindings_real (tree, tree, tree, int, int, int);
133 static int template_decl_level (tree);
134 static int check_cv_quals_for_unify (int, tree, tree);
135 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
136 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
137 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
138 static void regenerate_decl_from_template (tree, tree);
139 static tree most_specialized (tree, tree, tree);
140 static tree most_specialized_class (tree, tree);
141 static int template_class_depth_real (tree, int);
142 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
143 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
144 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
145 static void check_specialization_scope (void);
146 static tree process_partial_specialization (tree);
147 static void set_current_access_from_decl (tree);
148 static void check_default_tmpl_args (tree, tree, int, int);
149 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
150 static tree get_template_base (tree, tree, tree, tree);
151 static int verify_class_unification (tree, tree, tree);
152 static tree try_class_unification (tree, tree, tree, tree);
153 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
155 static tree determine_specialization (tree, tree, tree *, int, int);
156 static int template_args_equal (tree, tree);
157 static void tsubst_default_arguments (tree);
158 static tree for_each_template_parm_r (tree *, int *, void *);
159 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
160 static void copy_default_args_to_explicit_spec (tree);
161 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
162 static int eq_local_specializations (const void *, const void *);
163 static bool dependent_type_p_r (tree);
164 static tree tsubst (tree, tree, tsubst_flags_t, tree);
165 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
166 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
168 /* Make the current scope suitable for access checking when we are
169 processing T. T can be FUNCTION_DECL for instantiated function
170 template, or VAR_DECL for static member variable (need by
171 instantiate_decl). */
174 push_access_scope (tree t)
176 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
177 || TREE_CODE (t) == VAR_DECL);
179 if (DECL_CLASS_SCOPE_P (t))
180 push_nested_class (DECL_CONTEXT (t));
182 push_to_top_level ();
184 if (TREE_CODE (t) == FUNCTION_DECL)
186 saved_access_scope = tree_cons
187 (NULL_TREE, current_function_decl, saved_access_scope);
188 current_function_decl = t;
192 /* Restore the scope set up by push_access_scope. T is the node we
196 pop_access_scope (tree t)
198 if (TREE_CODE (t) == FUNCTION_DECL)
200 current_function_decl = TREE_VALUE (saved_access_scope);
201 saved_access_scope = TREE_CHAIN (saved_access_scope);
204 if (DECL_CLASS_SCOPE_P (t))
207 pop_from_top_level ();
210 /* Do any processing required when DECL (a member template
211 declaration) is finished. Returns the TEMPLATE_DECL corresponding
212 to DECL, unless it is a specialization, in which case the DECL
213 itself is returned. */
216 finish_member_template_decl (tree decl)
218 if (decl == error_mark_node)
219 return error_mark_node;
221 gcc_assert (DECL_P (decl));
223 if (TREE_CODE (decl) == TYPE_DECL)
227 type = TREE_TYPE (decl);
228 if (IS_AGGR_TYPE (type)
229 && CLASSTYPE_TEMPLATE_INFO (type)
230 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
232 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
233 check_member_template (tmpl);
238 else if (TREE_CODE (decl) == FIELD_DECL)
239 error ("data member %qD cannot be a member template", decl);
240 else if (DECL_TEMPLATE_INFO (decl))
242 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
244 check_member_template (DECL_TI_TEMPLATE (decl));
245 return DECL_TI_TEMPLATE (decl);
251 error ("invalid member template declaration %qD", decl);
253 return error_mark_node;
256 /* Returns the template nesting level of the indicated class TYPE.
266 A<T>::B<U> has depth two, while A<T> has depth one.
267 Both A<T>::B<int> and A<int>::B<U> have depth one, if
268 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
271 This function is guaranteed to return 0 if passed NULL_TREE so
272 that, for example, `template_class_depth (current_class_type)' is
276 template_class_depth_real (tree type, int count_specializations)
281 type && TREE_CODE (type) != NAMESPACE_DECL;
282 type = (TREE_CODE (type) == FUNCTION_DECL)
283 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
285 if (TREE_CODE (type) != FUNCTION_DECL)
287 if (CLASSTYPE_TEMPLATE_INFO (type)
288 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
289 && ((count_specializations
290 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
291 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
296 if (DECL_TEMPLATE_INFO (type)
297 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
298 && ((count_specializations
299 && DECL_TEMPLATE_SPECIALIZATION (type))
300 || uses_template_parms (DECL_TI_ARGS (type))))
308 /* Returns the template nesting level of the indicated class TYPE.
309 Like template_class_depth_real, but instantiations do not count in
313 template_class_depth (tree type)
315 return template_class_depth_real (type, /*count_specializations=*/0);
318 /* Returns 1 if processing DECL as part of do_pending_inlines
319 needs us to push template parms. */
322 inline_needs_template_parms (tree decl)
324 if (! DECL_TEMPLATE_INFO (decl))
327 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
328 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
331 /* Subroutine of maybe_begin_member_template_processing.
332 Push the template parms in PARMS, starting from LEVELS steps into the
333 chain, and ending at the beginning, since template parms are listed
337 push_inline_template_parms_recursive (tree parmlist, int levels)
339 tree parms = TREE_VALUE (parmlist);
343 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
345 ++processing_template_decl;
346 current_template_parms
347 = tree_cons (size_int (processing_template_decl),
348 parms, current_template_parms);
349 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
351 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
353 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
355 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
356 gcc_assert (DECL_P (parm));
358 switch (TREE_CODE (parm))
367 /* Make a CONST_DECL as is done in process_template_parm.
368 It is ugly that we recreate this here; the original
369 version built in process_template_parm is no longer
371 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
373 DECL_ARTIFICIAL (decl) = 1;
374 TREE_CONSTANT (decl) = 1;
375 TREE_INVARIANT (decl) = 1;
376 TREE_READONLY (decl) = 1;
377 DECL_INITIAL (decl) = DECL_INITIAL (parm);
378 SET_DECL_TEMPLATE_PARM_P (decl);
389 /* Restore the template parameter context for a member template or
390 a friend template defined in a class definition. */
393 maybe_begin_member_template_processing (tree decl)
398 if (inline_needs_template_parms (decl))
400 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
401 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
403 if (DECL_TEMPLATE_SPECIALIZATION (decl))
406 parms = TREE_CHAIN (parms);
409 push_inline_template_parms_recursive (parms, levels);
412 /* Remember how many levels of template parameters we pushed so that
413 we can pop them later. */
414 if (!inline_parm_levels)
415 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
416 if (inline_parm_levels_used == inline_parm_levels->num_elements)
417 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
418 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
419 ++inline_parm_levels_used;
422 /* Undo the effects of begin_member_template_processing. */
425 maybe_end_member_template_processing (void)
429 if (!inline_parm_levels_used)
432 --inline_parm_levels_used;
434 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
437 --processing_template_decl;
438 current_template_parms = TREE_CHAIN (current_template_parms);
443 /* Return a new template argument vector which contains all of ARGS,
444 but has as its innermost set of arguments the EXTRA_ARGS. */
447 add_to_template_args (tree args, tree extra_args)
454 extra_depth = TMPL_ARGS_DEPTH (extra_args);
455 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
457 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
458 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
460 for (j = 1; j <= extra_depth; ++j, ++i)
461 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
466 /* Like add_to_template_args, but only the outermost ARGS are added to
467 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
468 (EXTRA_ARGS) levels are added. This function is used to combine
469 the template arguments from a partial instantiation with the
470 template arguments used to attain the full instantiation from the
471 partial instantiation. */
474 add_outermost_template_args (tree args, tree extra_args)
478 /* If there are more levels of EXTRA_ARGS than there are ARGS,
479 something very fishy is going on. */
480 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
482 /* If *all* the new arguments will be the EXTRA_ARGS, just return
484 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
487 /* For the moment, we make ARGS look like it contains fewer levels. */
488 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
490 new_args = add_to_template_args (args, extra_args);
492 /* Now, we restore ARGS to its full dimensions. */
493 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
498 /* Return the N levels of innermost template arguments from the ARGS. */
501 get_innermost_template_args (tree args, int n)
509 /* If N is 1, just return the innermost set of template arguments. */
511 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
513 /* If we're not removing anything, just return the arguments we were
515 extra_levels = TMPL_ARGS_DEPTH (args) - n;
516 gcc_assert (extra_levels >= 0);
517 if (extra_levels == 0)
520 /* Make a new set of arguments, not containing the outer arguments. */
521 new_args = make_tree_vec (n);
522 for (i = 1; i <= n; ++i)
523 SET_TMPL_ARGS_LEVEL (new_args, i,
524 TMPL_ARGS_LEVEL (args, i + extra_levels));
529 /* We've got a template header coming up; push to a new level for storing
533 begin_template_parm_list (void)
535 /* We use a non-tag-transparent scope here, which causes pushtag to
536 put tags in this scope, rather than in the enclosing class or
537 namespace scope. This is the right thing, since we want
538 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
539 global template class, push_template_decl handles putting the
540 TEMPLATE_DECL into top-level scope. For a nested template class,
543 template <class T> struct S1 {
544 template <class T> struct S2 {};
547 pushtag contains special code to call pushdecl_with_scope on the
548 TEMPLATE_DECL for S2. */
549 begin_scope (sk_template_parms, NULL);
550 ++processing_template_decl;
551 ++processing_template_parmlist;
552 note_template_header (0);
555 /* This routine is called when a specialization is declared. If it is
556 invalid to declare a specialization here, an error is reported. */
559 check_specialization_scope (void)
561 tree scope = current_scope ();
565 An explicit specialization shall be declared in the namespace of
566 which the template is a member, or, for member templates, in the
567 namespace of which the enclosing class or enclosing class
568 template is a member. An explicit specialization of a member
569 function, member class or static data member of a class template
570 shall be declared in the namespace of which the class template
572 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
573 error ("explicit specialization in non-namespace scope %qD", scope);
577 In an explicit specialization declaration for a member of a class
578 template or a member template that appears in namespace scope,
579 the member template and some of its enclosing class templates may
580 remain unspecialized, except that the declaration shall not
581 explicitly specialize a class member template if its enclosing
582 class templates are not explicitly specialized as well. */
583 if (current_template_parms)
584 error ("enclosing class templates are not explicitly specialized");
587 /* We've just seen template <>. */
590 begin_specialization (void)
592 begin_scope (sk_template_spec, NULL);
593 note_template_header (1);
594 check_specialization_scope ();
597 /* Called at then end of processing a declaration preceded by
601 end_specialization (void)
604 reset_specialization ();
607 /* Any template <>'s that we have seen thus far are not referring to a
608 function specialization. */
611 reset_specialization (void)
613 processing_specialization = 0;
614 template_header_count = 0;
617 /* We've just seen a template header. If SPECIALIZATION is nonzero,
618 it was of the form template <>. */
621 note_template_header (int specialization)
623 processing_specialization = specialization;
624 template_header_count++;
627 /* We're beginning an explicit instantiation. */
630 begin_explicit_instantiation (void)
632 gcc_assert (!processing_explicit_instantiation);
633 processing_explicit_instantiation = true;
638 end_explicit_instantiation (void)
640 gcc_assert (processing_explicit_instantiation);
641 processing_explicit_instantiation = false;
644 /* A explicit specialization or partial specialization TMPL is being
645 declared. Check that the namespace in which the specialization is
646 occurring is permissible. Returns false iff it is invalid to
647 specialize TMPL in the current namespace. */
650 check_specialization_namespace (tree tmpl)
652 tree tpl_ns = decl_namespace_context (tmpl);
656 An explicit specialization shall be declared in the namespace of
657 which the template is a member, or, for member templates, in the
658 namespace of which the enclosing class or enclosing class
659 template is a member. An explicit specialization of a member
660 function, member class or static data member of a class template
661 shall be declared in the namespace of which the class template is
663 if (is_associated_namespace (current_namespace, tpl_ns))
664 /* Same or super-using namespace. */
668 pedwarn ("specialization of %qD in different namespace", tmpl);
669 cp_pedwarn_at (" from definition of %q#D", tmpl);
674 /* The TYPE is being declared. If it is a template type, that means it
675 is a partial specialization. Do appropriate error-checking. */
678 maybe_process_partial_specialization (tree type)
680 /* TYPE maybe an ERROR_MARK_NODE. */
681 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
683 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
685 /* This is for ordinary explicit specialization and partial
686 specialization of a template class such as:
688 template <> class C<int>;
692 template <class T> class C<T*>;
694 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
696 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
697 && !COMPLETE_TYPE_P (type))
699 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
700 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
701 if (processing_template_decl)
702 push_template_decl (TYPE_MAIN_DECL (type));
704 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
705 error ("specialization of %qT after instantiation", type);
707 else if (CLASS_TYPE_P (type)
708 && !CLASSTYPE_USE_TEMPLATE (type)
709 && CLASSTYPE_TEMPLATE_INFO (type)
710 && context && CLASS_TYPE_P (context)
711 && CLASSTYPE_TEMPLATE_INFO (context))
713 /* This is for an explicit specialization of member class
714 template according to [temp.expl.spec/18]:
716 template <> template <class U> class C<int>::D;
718 The context `C<int>' must be an implicit instantiation.
719 Otherwise this is just a member class template declared
722 template <> class C<int> { template <class U> class D; };
723 template <> template <class U> class C<int>::D;
725 In the first case, `C<int>::D' is a specialization of `C<T>::D'
726 while in the second case, `C<int>::D' is a primary template
727 and `C<T>::D' may not exist. */
729 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
730 && !COMPLETE_TYPE_P (type))
734 if (current_namespace
735 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
737 pedwarn ("specializing %q#T in different namespace", type);
738 cp_pedwarn_at (" from definition of %q#D",
739 CLASSTYPE_TI_TEMPLATE (type));
742 /* Check for invalid specialization after instantiation:
744 template <> template <> class C<int>::D<int>;
745 template <> template <class U> class C<int>::D; */
747 for (t = DECL_TEMPLATE_INSTANTIATIONS
748 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
749 t; t = TREE_CHAIN (t))
750 if (TREE_VALUE (t) != type
751 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
752 error ("specialization %qT after instantiation %qT",
753 type, TREE_VALUE (t));
755 /* Mark TYPE as a specialization. And as a result, we only
756 have one level of template argument for the innermost
758 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
759 CLASSTYPE_TI_ARGS (type)
760 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
763 else if (processing_specialization)
764 error ("explicit specialization of non-template %qT", type);
767 /* Returns nonzero if we can optimize the retrieval of specializations
768 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
769 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
772 optimize_specialization_lookup_p (tree tmpl)
774 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
775 && DECL_CLASS_SCOPE_P (tmpl)
776 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
778 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
779 /* The optimized lookup depends on the fact that the
780 template arguments for the member function template apply
781 purely to the containing class, which is not true if the
782 containing class is an explicit or partial
784 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
785 && !DECL_MEMBER_TEMPLATE_P (tmpl)
786 && !DECL_CONV_FN_P (tmpl)
787 /* It is possible to have a template that is not a member
788 template and is not a member of a template class:
790 template <typename T>
791 struct S { friend A::f(); };
793 Here, the friend function is a template, but the context does
794 not have template information. The optimized lookup relies
795 on having ARGS be the template arguments for both the class
796 and the function template. */
797 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
800 /* Retrieve the specialization (in the sense of [temp.spec] - a
801 specialization is either an instantiation or an explicit
802 specialization) of TMPL for the given template ARGS. If there is
803 no such specialization, return NULL_TREE. The ARGS are a vector of
804 arguments, or a vector of vectors of arguments, in the case of
805 templates with more than one level of parameters.
807 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
808 then we search for a partial specialization matching ARGS. This
809 parameter is ignored if TMPL is not a class template. */
812 retrieve_specialization (tree tmpl, tree args,
813 bool class_specializations_p)
815 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
817 /* There should be as many levels of arguments as there are
818 levels of parameters. */
819 gcc_assert (TMPL_ARGS_DEPTH (args)
820 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
822 if (optimize_specialization_lookup_p (tmpl))
825 tree class_specialization;
830 /* The template arguments actually apply to the containing
831 class. Find the class specialization with those
833 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
835 = retrieve_specialization (class_template, args,
836 /*class_specializations_p=*/false);
837 if (!class_specialization)
839 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
840 for the specialization. */
841 idx = class_method_index_for_fn (class_specialization, tmpl);
844 /* Iterate through the methods with the indicated name, looking
845 for the one that has an instance of TMPL. */
846 methods = CLASSTYPE_METHOD_VEC (class_specialization);
847 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
849 tree fn = OVL_CURRENT (fns);
850 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
860 /* Class templates store their instantiations on the
861 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
862 DECL_TEMPLATE_SPECIALIZATIONS list. */
863 if (!class_specializations_p
864 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
865 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
867 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
869 /* Iterate through the list until we find a matching template. */
870 while (*sp != NULL_TREE)
874 if (comp_template_args (TREE_PURPOSE (spec), args))
876 /* Use the move-to-front heuristic to speed up future
880 *sp = TREE_CHAIN (*sp);
881 TREE_CHAIN (spec) = *head;
884 return TREE_VALUE (spec);
886 sp = &TREE_CHAIN (spec);
893 /* Like retrieve_specialization, but for local declarations. */
896 retrieve_local_specialization (tree tmpl)
898 tree spec = htab_find_with_hash (local_specializations, tmpl,
899 htab_hash_pointer (tmpl));
900 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
903 /* Returns nonzero iff DECL is a specialization of TMPL. */
906 is_specialization_of (tree decl, tree tmpl)
910 if (TREE_CODE (decl) == FUNCTION_DECL)
914 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
920 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
922 for (t = TREE_TYPE (decl);
924 t = CLASSTYPE_USE_TEMPLATE (t)
925 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
926 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
933 /* Returns nonzero iff DECL is a specialization of friend declaration
934 FRIEND according to [temp.friend]. */
937 is_specialization_of_friend (tree decl, tree friend)
939 bool need_template = true;
942 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
943 || TREE_CODE (decl) == TYPE_DECL);
945 /* For [temp.friend/6] when FRIEND is an ordinary member function
946 of a template class, we want to check if DECL is a specialization
948 if (TREE_CODE (friend) == FUNCTION_DECL
949 && DECL_TEMPLATE_INFO (friend)
950 && !DECL_USE_TEMPLATE (friend))
952 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
953 friend = DECL_TI_TEMPLATE (friend);
954 need_template = false;
956 else if (TREE_CODE (friend) == TEMPLATE_DECL
957 && !PRIMARY_TEMPLATE_P (friend))
958 need_template = false;
960 /* There is nothing to do if this is not a template friend. */
961 if (TREE_CODE (friend) != TEMPLATE_DECL)
964 if (is_specialization_of (decl, friend))
968 A member of a class template may be declared to be a friend of a
969 non-template class. In this case, the corresponding member of
970 every specialization of the class template is a friend of the
971 class granting friendship.
973 For example, given a template friend declaration
975 template <class T> friend void A<T>::f();
977 the member function below is considered a friend
979 template <> struct A<int> {
983 For this type of template friend, TEMPLATE_DEPTH below will be
984 nonzero. To determine if DECL is a friend of FRIEND, we first
985 check if the enclosing class is a specialization of another. */
987 template_depth = template_class_depth (DECL_CONTEXT (friend));
989 && DECL_CLASS_SCOPE_P (decl)
990 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
991 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
993 /* Next, we check the members themselves. In order to handle
994 a few tricky cases, such as when FRIEND's are
996 template <class T> friend void A<T>::g(T t);
997 template <class T> template <T t> friend void A<T>::h();
1001 void A<int>::g(int);
1002 template <int> void A<int>::h();
1004 we need to figure out ARGS, the template arguments from
1005 the context of DECL. This is required for template substitution
1006 of `T' in the function parameter of `g' and template parameter
1007 of `h' in the above examples. Here ARGS corresponds to `int'. */
1009 tree context = DECL_CONTEXT (decl);
1010 tree args = NULL_TREE;
1011 int current_depth = 0;
1013 while (current_depth < template_depth)
1015 if (CLASSTYPE_TEMPLATE_INFO (context))
1017 if (current_depth == 0)
1018 args = TYPE_TI_ARGS (context);
1020 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1023 context = TYPE_CONTEXT (context);
1026 if (TREE_CODE (decl) == FUNCTION_DECL)
1031 tree friend_args_type;
1032 tree decl_args_type;
1034 /* Make sure that both DECL and FRIEND are templates or
1036 is_template = DECL_TEMPLATE_INFO (decl)
1037 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1038 if (need_template ^ is_template)
1040 else if (is_template)
1042 /* If both are templates, check template parameter list. */
1044 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1046 if (!comp_template_parms
1047 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1051 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1054 decl_type = TREE_TYPE (decl);
1056 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1057 tf_none, NULL_TREE);
1058 if (friend_type == error_mark_node)
1061 /* Check if return types match. */
1062 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1065 /* Check if function parameter types match, ignoring the
1066 `this' parameter. */
1067 friend_args_type = TYPE_ARG_TYPES (friend_type);
1068 decl_args_type = TYPE_ARG_TYPES (decl_type);
1069 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1070 friend_args_type = TREE_CHAIN (friend_args_type);
1071 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1072 decl_args_type = TREE_CHAIN (decl_args_type);
1074 return compparms (decl_args_type, friend_args_type);
1078 /* DECL is a TYPE_DECL */
1080 tree decl_type = TREE_TYPE (decl);
1082 /* Make sure that both DECL and FRIEND are templates or
1085 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1086 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1088 if (need_template ^ is_template)
1090 else if (is_template)
1093 /* If both are templates, check the name of the two
1094 TEMPLATE_DECL's first because is_friend didn't. */
1095 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1096 != DECL_NAME (friend))
1099 /* Now check template parameter list. */
1101 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1103 return comp_template_parms
1104 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1108 return (DECL_NAME (decl)
1109 == DECL_NAME (friend));
1115 /* Register the specialization SPEC as a specialization of TMPL with
1116 the indicated ARGS. Returns SPEC, or an equivalent prior
1117 declaration, if available. */
1120 register_specialization (tree spec, tree tmpl, tree args)
1124 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1126 if (TREE_CODE (spec) == FUNCTION_DECL
1127 && uses_template_parms (DECL_TI_ARGS (spec)))
1128 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1129 register it; we want the corresponding TEMPLATE_DECL instead.
1130 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1131 the more obvious `uses_template_parms (spec)' to avoid problems
1132 with default function arguments. In particular, given
1133 something like this:
1135 template <class T> void f(T t1, T t = T())
1137 the default argument expression is not substituted for in an
1138 instantiation unless and until it is actually needed. */
1141 /* There should be as many levels of arguments as there are
1142 levels of parameters. */
1143 gcc_assert (TMPL_ARGS_DEPTH (args)
1144 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
1146 fn = retrieve_specialization (tmpl, args,
1147 /*class_specializations_p=*/false);
1148 /* We can sometimes try to re-register a specialization that we've
1149 already got. In particular, regenerate_decl_from_template calls
1150 duplicate_decls which will update the specialization list. But,
1151 we'll still get called again here anyhow. It's more convenient
1152 to simply allow this than to try to prevent it. */
1155 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1157 if (DECL_TEMPLATE_INSTANTIATION (fn))
1160 || DECL_EXPLICIT_INSTANTIATION (fn))
1162 error ("specialization of %qD after instantiation",
1168 /* This situation should occur only if the first
1169 specialization is an implicit instantiation, the
1170 second is an explicit specialization, and the
1171 implicit instantiation has not yet been used. That
1172 situation can occur if we have implicitly
1173 instantiated a member function and then specialized
1176 We can also wind up here if a friend declaration that
1177 looked like an instantiation turns out to be a
1180 template <class T> void foo(T);
1181 class S { friend void foo<>(int) };
1182 template <> void foo(int);
1184 We transform the existing DECL in place so that any
1185 pointers to it become pointers to the updated
1188 If there was a definition for the template, but not
1189 for the specialization, we want this to look as if
1190 there were no definition, and vice versa. */
1191 DECL_INITIAL (fn) = NULL_TREE;
1192 duplicate_decls (spec, fn);
1197 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1199 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
1200 /* Dup decl failed, but this is a new definition. Set the
1201 line number so any errors match this new
1203 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1209 /* A specialization must be declared in the same namespace as the
1210 template it is specializing. */
1211 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1212 && !check_specialization_namespace (tmpl))
1213 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1215 if (!optimize_specialization_lookup_p (tmpl))
1216 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1217 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1222 /* Unregister the specialization SPEC as a specialization of TMPL.
1223 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1224 if the SPEC was listed as a specialization of TMPL. */
1227 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1231 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1233 s = &TREE_CHAIN (*s))
1234 if (TREE_VALUE (*s) == spec)
1237 *s = TREE_CHAIN (*s);
1239 TREE_VALUE (*s) = new_spec;
1246 /* Compare an entry in the local specializations hash table P1 (which
1247 is really a pointer to a TREE_LIST) with P2 (which is really a
1251 eq_local_specializations (const void *p1, const void *p2)
1253 return TREE_VALUE ((tree) p1) == (tree) p2;
1256 /* Hash P1, an entry in the local specializations table. */
1259 hash_local_specialization (const void* p1)
1261 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1264 /* Like register_specialization, but for local declarations. We are
1265 registering SPEC, an instantiation of TMPL. */
1268 register_local_specialization (tree spec, tree tmpl)
1272 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1273 htab_hash_pointer (tmpl), INSERT);
1274 *slot = build_tree_list (spec, tmpl);
1277 /* Print the list of candidate FNS in an error message. */
1280 print_candidates (tree fns)
1284 const char *str = "candidates are:";
1286 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1290 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1291 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
1296 /* Returns the template (one of the functions given by TEMPLATE_ID)
1297 which can be specialized to match the indicated DECL with the
1298 explicit template args given in TEMPLATE_ID. The DECL may be
1299 NULL_TREE if none is available. In that case, the functions in
1300 TEMPLATE_ID are non-members.
1302 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1303 specialization of a member template.
1305 The TEMPLATE_COUNT is the number of references to qualifying
1306 template classes that appeared in the name of the function. See
1307 check_explicit_specialization for a more accurate description.
1309 The template args (those explicitly specified and those deduced)
1310 are output in a newly created vector *TARGS_OUT.
1312 If it is impossible to determine the result, an error message is
1313 issued. The error_mark_node is returned to indicate failure. */
1316 determine_specialization (tree template_id,
1319 int need_member_template,
1324 tree explicit_targs;
1325 tree candidates = NULL_TREE;
1326 tree templates = NULL_TREE;
1328 struct cp_binding_level *b;
1330 *targs_out = NULL_TREE;
1332 if (template_id == error_mark_node)
1333 return error_mark_node;
1335 fns = TREE_OPERAND (template_id, 0);
1336 explicit_targs = TREE_OPERAND (template_id, 1);
1338 if (fns == error_mark_node)
1339 return error_mark_node;
1341 /* Check for baselinks. */
1342 if (BASELINK_P (fns))
1343 fns = BASELINK_FUNCTIONS (fns);
1345 if (!is_overloaded_fn (fns))
1347 error ("%qD is not a function template", fns);
1348 return error_mark_node;
1351 /* Count the number of template headers specified for this
1354 for (b = current_binding_level;
1355 b->kind == sk_template_parms || b->kind == sk_template_spec;
1359 for (; fns; fns = OVL_NEXT (fns))
1361 tree fn = OVL_CURRENT (fns);
1363 if (TREE_CODE (fn) == TEMPLATE_DECL)
1365 tree decl_arg_types;
1368 /* DECL might be a specialization of FN. */
1370 /* Adjust the type of DECL in case FN is a static member. */
1371 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1372 if (DECL_STATIC_FUNCTION_P (fn)
1373 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1374 decl_arg_types = TREE_CHAIN (decl_arg_types);
1376 /* Check that the number of function parameters matches.
1378 template <class T> void f(int i = 0);
1379 template <> void f<int>();
1380 The specialization f<int> is invalid but is not caught
1381 by get_bindings below. */
1383 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1384 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1387 /* For a non-static member function, we need to make sure that
1388 the const qualification is the same. This can be done by
1389 checking the 'this' in the argument list. */
1390 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1391 && !same_type_p (TREE_VALUE (fn_arg_types),
1392 TREE_VALUE (decl_arg_types)))
1395 /* In case of explicit specialization, we need to check if
1396 the number of template headers appearing in the specialization
1397 is correct. This is usually done in check_explicit_specialization,
1398 but the check done there cannot be exhaustive when specializing
1399 member functions. Consider the following code:
1401 template <> void A<int>::f(int);
1402 template <> template <> void A<int>::f(int);
1404 Assuming that A<int> is not itself an explicit specialization
1405 already, the first line specializes "f" which is a non-template
1406 member function, whilst the second line specializes "f" which
1407 is a template member function. So both lines are syntactically
1408 correct, and check_explicit_specialization does not reject
1411 Here, we can do better, as we are matching the specialization
1412 against the declarations. We count the number of template
1413 headers, and we check if they match TEMPLATE_COUNT + 1
1414 (TEMPLATE_COUNT is the number of qualifying template classes,
1415 plus there must be another header for the member template
1418 Notice that if header_count is zero, this is not a
1419 specialization but rather a template instantiation, so there
1420 is no check we can perform here. */
1421 if (header_count && header_count != template_count + 1)
1424 /* See whether this function might be a specialization of this
1426 targs = get_bindings (fn, decl, explicit_targs);
1429 /* We cannot deduce template arguments that when used to
1430 specialize TMPL will produce DECL. */
1433 /* Save this template, and the arguments deduced. */
1434 templates = tree_cons (targs, fn, templates);
1436 else if (need_member_template)
1437 /* FN is an ordinary member function, and we need a
1438 specialization of a member template. */
1440 else if (TREE_CODE (fn) != FUNCTION_DECL)
1441 /* We can get IDENTIFIER_NODEs here in certain erroneous
1444 else if (!DECL_FUNCTION_MEMBER_P (fn))
1445 /* This is just an ordinary non-member function. Nothing can
1446 be a specialization of that. */
1448 else if (DECL_ARTIFICIAL (fn))
1449 /* Cannot specialize functions that are created implicitly. */
1453 tree decl_arg_types;
1455 /* This is an ordinary member function. However, since
1456 we're here, we can assume it's enclosing class is a
1457 template class. For example,
1459 template <typename T> struct S { void f(); };
1460 template <> void S<int>::f() {}
1462 Here, S<int>::f is a non-template, but S<int> is a
1463 template class. If FN has the same type as DECL, we
1464 might be in business. */
1466 if (!DECL_TEMPLATE_INFO (fn))
1467 /* Its enclosing class is an explicit specialization
1468 of a template class. This is not a candidate. */
1471 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1472 TREE_TYPE (TREE_TYPE (fn))))
1473 /* The return types differ. */
1476 /* Adjust the type of DECL in case FN is a static member. */
1477 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1478 if (DECL_STATIC_FUNCTION_P (fn)
1479 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1480 decl_arg_types = TREE_CHAIN (decl_arg_types);
1482 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1485 candidates = tree_cons (NULL_TREE, fn, candidates);
1489 if (templates && TREE_CHAIN (templates))
1495 It is possible for a specialization with a given function
1496 signature to be instantiated from more than one function
1497 template. In such cases, explicit specification of the
1498 template arguments must be used to uniquely identify the
1499 function template specialization being specialized.
1501 Note that here, there's no suggestion that we're supposed to
1502 determine which of the candidate templates is most
1503 specialized. However, we, also have:
1507 Partial ordering of overloaded function template
1508 declarations is used in the following contexts to select
1509 the function template to which a function template
1510 specialization refers:
1512 -- when an explicit specialization refers to a function
1515 So, we do use the partial ordering rules, at least for now.
1516 This extension can only serve to make invalid programs valid,
1517 so it's safe. And, there is strong anecdotal evidence that
1518 the committee intended the partial ordering rules to apply;
1519 the EDG front-end has that behavior, and John Spicer claims
1520 that the committee simply forgot to delete the wording in
1521 [temp.expl.spec]. */
1522 tree tmpl = most_specialized (templates, decl, explicit_targs);
1523 if (tmpl && tmpl != error_mark_node)
1525 targs = get_bindings (tmpl, decl, explicit_targs);
1526 templates = tree_cons (targs, tmpl, NULL_TREE);
1530 if (templates == NULL_TREE && candidates == NULL_TREE)
1532 cp_error_at ("template-id %qD for %q+D does not match any template "
1535 return error_mark_node;
1537 else if ((templates && TREE_CHAIN (templates))
1538 || (candidates && TREE_CHAIN (candidates))
1539 || (templates && candidates))
1541 cp_error_at ("ambiguous template specialization %qD for %q+D",
1543 chainon (candidates, templates);
1544 print_candidates (candidates);
1545 return error_mark_node;
1548 /* We have one, and exactly one, match. */
1551 /* It was a specialization of an ordinary member function in a
1553 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1554 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1557 /* It was a specialization of a template. */
1558 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1559 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1561 *targs_out = copy_node (targs);
1562 SET_TMPL_ARGS_LEVEL (*targs_out,
1563 TMPL_ARGS_DEPTH (*targs_out),
1564 TREE_PURPOSE (templates));
1567 *targs_out = TREE_PURPOSE (templates);
1568 return TREE_VALUE (templates);
1571 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1572 but with the default argument values filled in from those in the
1576 copy_default_args_to_explicit_spec_1 (tree spec_types,
1579 tree new_spec_types;
1584 if (spec_types == void_list_node)
1585 return void_list_node;
1587 /* Substitute into the rest of the list. */
1589 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1590 TREE_CHAIN (tmpl_types));
1592 /* Add the default argument for this parameter. */
1593 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1594 TREE_VALUE (spec_types),
1598 /* DECL is an explicit specialization. Replicate default arguments
1599 from the template it specializes. (That way, code like:
1601 template <class T> void f(T = 3);
1602 template <> void f(double);
1605 works, as required.) An alternative approach would be to look up
1606 the correct default arguments at the call-site, but this approach
1607 is consistent with how implicit instantiations are handled. */
1610 copy_default_args_to_explicit_spec (tree decl)
1615 tree new_spec_types;
1619 tree object_type = NULL_TREE;
1620 tree in_charge = NULL_TREE;
1621 tree vtt = NULL_TREE;
1623 /* See if there's anything we need to do. */
1624 tmpl = DECL_TI_TEMPLATE (decl);
1625 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1626 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1627 if (TREE_PURPOSE (t))
1632 old_type = TREE_TYPE (decl);
1633 spec_types = TYPE_ARG_TYPES (old_type);
1635 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1637 /* Remove the this pointer, but remember the object's type for
1639 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1640 spec_types = TREE_CHAIN (spec_types);
1641 tmpl_types = TREE_CHAIN (tmpl_types);
1643 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1645 /* DECL may contain more parameters than TMPL due to the extra
1646 in-charge parameter in constructors and destructors. */
1647 in_charge = spec_types;
1648 spec_types = TREE_CHAIN (spec_types);
1650 if (DECL_HAS_VTT_PARM_P (decl))
1653 spec_types = TREE_CHAIN (spec_types);
1657 /* Compute the merged default arguments. */
1659 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1661 /* Compute the new FUNCTION_TYPE. */
1665 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1670 /* Put the in-charge parameter back. */
1671 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1672 TREE_VALUE (in_charge),
1675 new_type = build_method_type_directly (object_type,
1676 TREE_TYPE (old_type),
1680 new_type = build_function_type (TREE_TYPE (old_type),
1682 new_type = cp_build_type_attribute_variant (new_type,
1683 TYPE_ATTRIBUTES (old_type));
1684 new_type = build_exception_variant (new_type,
1685 TYPE_RAISES_EXCEPTIONS (old_type));
1686 TREE_TYPE (decl) = new_type;
1689 /* Check to see if the function just declared, as indicated in
1690 DECLARATOR, and in DECL, is a specialization of a function
1691 template. We may also discover that the declaration is an explicit
1692 instantiation at this point.
1694 Returns DECL, or an equivalent declaration that should be used
1695 instead if all goes well. Issues an error message if something is
1696 amiss. Returns error_mark_node if the error is not easily
1699 FLAGS is a bitmask consisting of the following flags:
1701 2: The function has a definition.
1702 4: The function is a friend.
1704 The TEMPLATE_COUNT is the number of references to qualifying
1705 template classes that appeared in the name of the function. For
1708 template <class T> struct S { void f(); };
1711 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1712 classes are not counted in the TEMPLATE_COUNT, so that in
1714 template <class T> struct S {};
1715 template <> struct S<int> { void f(); }
1716 template <> void S<int>::f();
1718 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1719 invalid; there should be no template <>.)
1721 If the function is a specialization, it is marked as such via
1722 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1723 is set up correctly, and it is added to the list of specializations
1724 for that template. */
1727 check_explicit_specialization (tree declarator,
1732 int have_def = flags & 2;
1733 int is_friend = flags & 4;
1734 int specialization = 0;
1735 int explicit_instantiation = 0;
1736 int member_specialization = 0;
1737 tree ctype = DECL_CLASS_CONTEXT (decl);
1738 tree dname = DECL_NAME (decl);
1741 tsk = current_tmpl_spec_kind (template_count);
1746 if (processing_specialization)
1749 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1751 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1754 /* This could be something like:
1756 template <class T> void f(T);
1757 class S { friend void f<>(int); } */
1761 /* This case handles bogus declarations like template <>
1762 template <class T> void f<int>(); */
1764 error ("template-id %qD in declaration of primary template",
1771 case tsk_invalid_member_spec:
1772 /* The error has already been reported in
1773 check_specialization_scope. */
1774 return error_mark_node;
1776 case tsk_invalid_expl_inst:
1777 error ("template parameter list used in explicit instantiation");
1783 error ("definition provided for explicit instantiation");
1785 explicit_instantiation = 1;
1788 case tsk_excessive_parms:
1789 case tsk_insufficient_parms:
1790 if (tsk == tsk_excessive_parms)
1791 error ("too many template parameter lists in declaration of %qD",
1793 else if (template_header_count)
1794 error("too few template parameter lists in declaration of %qD", decl);
1796 error("explicit specialization of %qD must be introduced by "
1797 "%<template <>%>", decl);
1801 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1803 member_specialization = 1;
1809 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1811 /* This case handles bogus declarations like template <>
1812 template <class T> void f<int>(); */
1814 if (uses_template_parms (declarator))
1815 error ("function template partial specialization %qD "
1816 "is not allowed", declarator);
1818 error ("template-id %qD in declaration of primary template",
1823 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1824 /* This is a specialization of a member template, without
1825 specialization the containing class. Something like:
1827 template <class T> struct S {
1828 template <class U> void f (U);
1830 template <> template <class U> void S<int>::f(U) {}
1832 That's a specialization -- but of the entire template. */
1840 if (specialization || member_specialization)
1842 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1843 for (; t; t = TREE_CHAIN (t))
1844 if (TREE_PURPOSE (t))
1847 ("default argument specified in explicit specialization");
1850 if (current_lang_name == lang_name_c)
1851 error ("template specialization with C linkage");
1854 if (specialization || member_specialization || explicit_instantiation)
1856 tree tmpl = NULL_TREE;
1857 tree targs = NULL_TREE;
1859 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1860 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1864 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1869 /* If there is no class context, the explicit instantiation
1870 must be at namespace scope. */
1871 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1873 /* Find the namespace binding, using the declaration
1875 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1878 declarator = lookup_template_function (fns, NULL_TREE);
1881 if (declarator == error_mark_node)
1882 return error_mark_node;
1884 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1886 if (!explicit_instantiation)
1887 /* A specialization in class scope. This is invalid,
1888 but the error will already have been flagged by
1889 check_specialization_scope. */
1890 return error_mark_node;
1893 /* It's not valid to write an explicit instantiation in
1896 class C { template void f(); }
1898 This case is caught by the parser. However, on
1901 template class C { void f(); };
1903 (which is invalid) we can get here. The error will be
1910 else if (ctype != NULL_TREE
1911 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1914 /* Find the list of functions in ctype that have the same
1915 name as the declared function. */
1916 tree name = TREE_OPERAND (declarator, 0);
1917 tree fns = NULL_TREE;
1920 if (constructor_name_p (name, ctype))
1922 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1924 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1925 : !TYPE_HAS_DESTRUCTOR (ctype))
1927 /* From [temp.expl.spec]:
1929 If such an explicit specialization for the member
1930 of a class template names an implicitly-declared
1931 special member function (clause _special_), the
1932 program is ill-formed.
1934 Similar language is found in [temp.explicit]. */
1935 error ("specialization of implicitly-declared special member function");
1936 return error_mark_node;
1939 name = is_constructor ? ctor_identifier : dtor_identifier;
1942 if (!DECL_CONV_FN_P (decl))
1944 idx = lookup_fnfields_1 (ctype, name);
1946 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1953 /* For a type-conversion operator, we cannot do a
1954 name-based lookup. We might be looking for `operator
1955 int' which will be a specialization of `operator T'.
1956 So, we find *all* the conversion operators, and then
1957 select from them. */
1960 methods = CLASSTYPE_METHOD_VEC (ctype);
1962 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1963 VEC_iterate (tree, methods, idx, ovl);
1966 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1967 /* There are no more conversion functions. */
1970 /* Glue all these conversion functions together
1971 with those we already have. */
1972 for (; ovl; ovl = OVL_NEXT (ovl))
1973 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1977 if (fns == NULL_TREE)
1979 error ("no member function %qD declared in %qT", name, ctype);
1980 return error_mark_node;
1983 TREE_OPERAND (declarator, 0) = fns;
1986 /* Figure out what exactly is being specialized at this point.
1987 Note that for an explicit instantiation, even one for a
1988 member function, we cannot tell apriori whether the
1989 instantiation is for a member template, or just a member
1990 function of a template class. Even if a member template is
1991 being instantiated, the member template arguments may be
1992 elided if they can be deduced from the rest of the
1994 tmpl = determine_specialization (declarator, decl,
1996 member_specialization,
1999 if (!tmpl || tmpl == error_mark_node)
2000 /* We couldn't figure out what this declaration was
2002 return error_mark_node;
2005 tree gen_tmpl = most_general_template (tmpl);
2007 if (explicit_instantiation)
2009 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2010 is done by do_decl_instantiation later. */
2012 int arg_depth = TMPL_ARGS_DEPTH (targs);
2013 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2015 if (arg_depth > parm_depth)
2017 /* If TMPL is not the most general template (for
2018 example, if TMPL is a friend template that is
2019 injected into namespace scope), then there will
2020 be too many levels of TARGS. Remove some of them
2025 new_targs = make_tree_vec (parm_depth);
2026 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2027 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2028 = TREE_VEC_ELT (targs, i);
2032 return instantiate_template (tmpl, targs, tf_error);
2035 /* If we thought that the DECL was a member function, but it
2036 turns out to be specializing a static member function,
2037 make DECL a static member function as well. */
2038 if (DECL_STATIC_FUNCTION_P (tmpl)
2039 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2040 revert_static_member_fn (decl);
2042 /* If this is a specialization of a member template of a
2043 template class. In we want to return the TEMPLATE_DECL,
2044 not the specialization of it. */
2045 if (tsk == tsk_template)
2047 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2048 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2051 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2052 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2053 = DECL_SOURCE_LOCATION (decl);
2058 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2059 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2061 /* Inherit default function arguments from the template
2062 DECL is specializing. */
2063 copy_default_args_to_explicit_spec (decl);
2065 /* This specialization has the same protection as the
2066 template it specializes. */
2067 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2068 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2070 if (is_friend && !have_def)
2071 /* This is not really a declaration of a specialization.
2072 It's just the name of an instantiation. But, it's not
2073 a request for an instantiation, either. */
2074 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2075 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2076 /* This is indeed a specialization. In case of constructors
2077 and destructors, we need in-charge and not-in-charge
2078 versions in V3 ABI. */
2079 clone_function_decl (decl, /*update_method_vec_p=*/0);
2081 /* Register this specialization so that we can find it
2083 decl = register_specialization (decl, gen_tmpl, targs);
2090 /* TYPE is being declared. Verify that the use of template headers
2091 and such is reasonable. Issue error messages if not. */
2094 maybe_check_template_type (tree type)
2096 if (template_header_count)
2098 /* We are in the scope of some `template <...>' header. */
2101 = template_class_depth_real (TYPE_CONTEXT (type),
2102 /*count_specializations=*/1);
2104 if (template_header_count <= context_depth)
2105 /* This is OK; the template headers are for the context. We
2106 are actually too lenient here; like
2107 check_explicit_specialization we should consider the number
2108 of template types included in the actual declaration. For
2111 template <class T> struct S {
2112 template <class U> template <class V>
2118 template <class T> struct S {
2119 template <class U> struct I;
2122 template <class T> template <class U.
2127 else if (template_header_count > context_depth + 1)
2128 /* There are two many template parameter lists. */
2129 error ("too many template parameter lists in declaration of %qT", type);
2133 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2134 parameters. These are represented in the same format used for
2135 DECL_TEMPLATE_PARMS. */
2138 comp_template_parms (tree parms1, tree parms2)
2143 if (parms1 == parms2)
2146 for (p1 = parms1, p2 = parms2;
2147 p1 != NULL_TREE && p2 != NULL_TREE;
2148 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2150 tree t1 = TREE_VALUE (p1);
2151 tree t2 = TREE_VALUE (p2);
2154 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2155 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2157 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2160 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2162 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2163 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2165 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2168 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2170 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2175 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2176 /* One set of parameters has more parameters lists than the
2183 /* Complain if DECL shadows a template parameter.
2185 [temp.local]: A template-parameter shall not be redeclared within its
2186 scope (including nested scopes). */
2189 check_template_shadow (tree decl)
2193 /* If we're not in a template, we can't possibly shadow a template
2195 if (!current_template_parms)
2198 /* Figure out what we're shadowing. */
2199 if (TREE_CODE (decl) == OVERLOAD)
2200 decl = OVL_CURRENT (decl);
2201 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2203 /* If there's no previous binding for this name, we're not shadowing
2204 anything, let alone a template parameter. */
2208 /* If we're not shadowing a template parameter, we're done. Note
2209 that OLDDECL might be an OVERLOAD (or perhaps even an
2210 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2212 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2215 /* We check for decl != olddecl to avoid bogus errors for using a
2216 name inside a class. We check TPFI to avoid duplicate errors for
2217 inline member templates. */
2219 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2222 cp_error_at ("declaration of %q#D", decl);
2223 cp_error_at (" shadows template parm %q#D", olddecl);
2226 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2227 ORIG_LEVEL, DECL, and TYPE. */
2230 build_template_parm_index (int index,
2236 tree t = make_node (TEMPLATE_PARM_INDEX);
2237 TEMPLATE_PARM_IDX (t) = index;
2238 TEMPLATE_PARM_LEVEL (t) = level;
2239 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2240 TEMPLATE_PARM_DECL (t) = decl;
2241 TREE_TYPE (t) = type;
2242 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2243 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2244 TREE_READONLY (t) = TREE_READONLY (decl);
2249 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2250 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2251 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2252 new one is created. */
2255 reduce_template_parm_level (tree index, tree type, int levels)
2257 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2258 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2259 != TEMPLATE_PARM_LEVEL (index) - levels))
2261 tree orig_decl = TEMPLATE_PARM_DECL (index);
2264 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2265 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2266 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2267 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2268 DECL_ARTIFICIAL (decl) = 1;
2269 SET_DECL_TEMPLATE_PARM_P (decl);
2271 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2272 TEMPLATE_PARM_LEVEL (index) - levels,
2273 TEMPLATE_PARM_ORIG_LEVEL (index),
2275 TEMPLATE_PARM_DESCENDANTS (index) = t;
2277 /* Template template parameters need this. */
2278 DECL_TEMPLATE_PARMS (decl)
2279 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2282 return TEMPLATE_PARM_DESCENDANTS (index);
2285 /* Process information from new template parameter NEXT and append it to the
2286 LIST being built. This new parameter is a non-type parameter iff
2287 IS_NON_TYPE is true. */
2290 process_template_parm (tree list, tree next, bool is_non_type)
2298 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2299 defval = TREE_PURPOSE (parm);
2303 tree p = TREE_VALUE (tree_last (list));
2305 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2306 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2308 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2316 parm = TREE_VALUE (parm);
2318 SET_DECL_TEMPLATE_PARM_P (parm);
2322 The top-level cv-qualifiers on the template-parameter are
2323 ignored when determining its type. */
2324 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2326 /* A template parameter is not modifiable. */
2327 TREE_CONSTANT (parm) = 1;
2328 TREE_INVARIANT (parm) = 1;
2329 TREE_READONLY (parm) = 1;
2330 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2331 TREE_TYPE (parm) = void_type_node;
2332 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2333 TREE_CONSTANT (decl) = 1;
2334 TREE_INVARIANT (decl) = 1;
2335 TREE_READONLY (decl) = 1;
2336 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2337 = build_template_parm_index (idx, processing_template_decl,
2338 processing_template_decl,
2339 decl, TREE_TYPE (parm));
2344 parm = TREE_VALUE (TREE_VALUE (parm));
2346 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2348 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2349 /* This is for distinguishing between real templates and template
2350 template parameters */
2351 TREE_TYPE (parm) = t;
2352 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2357 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2358 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2359 decl = build_decl (TYPE_DECL, parm, t);
2362 TYPE_NAME (t) = decl;
2363 TYPE_STUB_DECL (t) = decl;
2365 TEMPLATE_TYPE_PARM_INDEX (t)
2366 = build_template_parm_index (idx, processing_template_decl,
2367 processing_template_decl,
2368 decl, TREE_TYPE (parm));
2370 DECL_ARTIFICIAL (decl) = 1;
2371 SET_DECL_TEMPLATE_PARM_P (decl);
2373 parm = build_tree_list (defval, parm);
2374 return chainon (list, parm);
2377 /* The end of a template parameter list has been reached. Process the
2378 tree list into a parameter vector, converting each parameter into a more
2379 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2383 end_template_parm_list (tree parms)
2387 tree saved_parmlist = make_tree_vec (list_length (parms));
2389 current_template_parms
2390 = tree_cons (size_int (processing_template_decl),
2391 saved_parmlist, current_template_parms);
2393 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2395 next = TREE_CHAIN (parm);
2396 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2397 TREE_CHAIN (parm) = NULL_TREE;
2400 --processing_template_parmlist;
2402 return saved_parmlist;
2405 /* end_template_decl is called after a template declaration is seen. */
2408 end_template_decl (void)
2410 reset_specialization ();
2412 if (! processing_template_decl)
2415 /* This matches the pushlevel in begin_template_parm_list. */
2418 --processing_template_decl;
2419 current_template_parms = TREE_CHAIN (current_template_parms);
2422 /* Given a template argument vector containing the template PARMS.
2423 The innermost PARMS are given first. */
2426 current_template_args (void)
2429 tree args = NULL_TREE;
2430 int length = TMPL_PARMS_DEPTH (current_template_parms);
2433 /* If there is only one level of template parameters, we do not
2434 create a TREE_VEC of TREE_VECs. Instead, we return a single
2435 TREE_VEC containing the arguments. */
2437 args = make_tree_vec (length);
2439 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2441 tree a = copy_node (TREE_VALUE (header));
2444 TREE_TYPE (a) = NULL_TREE;
2445 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2447 tree t = TREE_VEC_ELT (a, i);
2449 /* T will be a list if we are called from within a
2450 begin/end_template_parm_list pair, but a vector directly
2451 if within a begin/end_member_template_processing pair. */
2452 if (TREE_CODE (t) == TREE_LIST)
2456 if (TREE_CODE (t) == TYPE_DECL
2457 || TREE_CODE (t) == TEMPLATE_DECL)
2460 t = DECL_INITIAL (t);
2461 TREE_VEC_ELT (a, i) = t;
2466 TREE_VEC_ELT (args, --l) = a;
2474 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2475 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2476 a member template. Used by push_template_decl below. */
2479 build_template_decl (tree decl, tree parms, bool member_template_p)
2481 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2482 DECL_TEMPLATE_PARMS (tmpl) = parms;
2483 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2484 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2485 if (DECL_LANG_SPECIFIC (decl))
2487 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2488 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2489 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2490 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2491 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2492 if (DECL_OVERLOADED_OPERATOR_P (decl))
2493 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2494 DECL_OVERLOADED_OPERATOR_P (decl));
2500 struct template_parm_data
2502 /* The level of the template parameters we are currently
2506 /* The index of the specialization argument we are currently
2510 /* An array whose size is the number of template parameters. The
2511 elements are nonzero if the parameter has been used in any one
2512 of the arguments processed so far. */
2515 /* An array whose size is the number of template arguments. The
2516 elements are nonzero if the argument makes use of template
2517 parameters of this level. */
2518 int* arg_uses_template_parms;
2521 /* Subroutine of push_template_decl used to see if each template
2522 parameter in a partial specialization is used in the explicit
2523 argument list. If T is of the LEVEL given in DATA (which is
2524 treated as a template_parm_data*), then DATA->PARMS is marked
2528 mark_template_parm (tree t, void* data)
2532 struct template_parm_data* tpd = (struct template_parm_data*) data;
2534 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2536 level = TEMPLATE_PARM_LEVEL (t);
2537 idx = TEMPLATE_PARM_IDX (t);
2541 level = TEMPLATE_TYPE_LEVEL (t);
2542 idx = TEMPLATE_TYPE_IDX (t);
2545 if (level == tpd->level)
2547 tpd->parms[idx] = 1;
2548 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2551 /* Return zero so that for_each_template_parm will continue the
2552 traversal of the tree; we want to mark *every* template parm. */
2556 /* Process the partial specialization DECL. */
2559 process_partial_specialization (tree decl)
2561 tree type = TREE_TYPE (decl);
2562 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2563 tree specargs = CLASSTYPE_TI_ARGS (type);
2564 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2565 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2566 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2567 int nargs = TREE_VEC_LENGTH (inner_args);
2568 int ntparms = TREE_VEC_LENGTH (inner_parms);
2570 int did_error_intro = 0;
2571 struct template_parm_data tpd;
2572 struct template_parm_data tpd2;
2574 /* We check that each of the template parameters given in the
2575 partial specialization is used in the argument list to the
2576 specialization. For example:
2578 template <class T> struct S;
2579 template <class T> struct S<T*>;
2581 The second declaration is OK because `T*' uses the template
2582 parameter T, whereas
2584 template <class T> struct S<int>;
2586 is no good. Even trickier is:
2597 The S2<T> declaration is actually invalid; it is a
2598 full-specialization. Of course,
2601 struct S2<T (*)(U)>;
2603 or some such would have been OK. */
2604 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2605 tpd.parms = alloca (sizeof (int) * ntparms);
2606 memset (tpd.parms, 0, sizeof (int) * ntparms);
2608 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2609 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2610 for (i = 0; i < nargs; ++i)
2612 tpd.current_arg = i;
2613 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2614 &mark_template_parm,
2618 for (i = 0; i < ntparms; ++i)
2619 if (tpd.parms[i] == 0)
2621 /* One of the template parms was not used in the
2623 if (!did_error_intro)
2625 error ("template parameters not used in partial specialization:");
2626 did_error_intro = 1;
2629 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2632 /* [temp.class.spec]
2634 The argument list of the specialization shall not be identical to
2635 the implicit argument list of the primary template. */
2636 if (comp_template_args
2638 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2640 error ("partial specialization %qT does not specialize any template arguments", type);
2642 /* [temp.class.spec]
2644 A partially specialized non-type argument expression shall not
2645 involve template parameters of the partial specialization except
2646 when the argument expression is a simple identifier.
2648 The type of a template parameter corresponding to a specialized
2649 non-type argument shall not be dependent on a parameter of the
2651 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2653 for (i = 0; i < nargs; ++i)
2655 tree arg = TREE_VEC_ELT (inner_args, i);
2656 if (/* These first two lines are the `non-type' bit. */
2658 && TREE_CODE (arg) != TEMPLATE_DECL
2659 /* This next line is the `argument expression is not just a
2660 simple identifier' condition and also the `specialized
2661 non-type argument' bit. */
2662 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2664 if (tpd.arg_uses_template_parms[i])
2665 error ("template argument %qE involves template parameter(s)", arg);
2668 /* Look at the corresponding template parameter,
2669 marking which template parameters its type depends
2672 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2677 /* We haven't yet initialized TPD2. Do so now. */
2678 tpd2.arg_uses_template_parms
2679 = alloca (sizeof (int) * nargs);
2680 /* The number of parameters here is the number in the
2681 main template, which, as checked in the assertion
2683 tpd2.parms = alloca (sizeof (int) * nargs);
2685 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2688 /* Mark the template parameters. But this time, we're
2689 looking for the template parameters of the main
2690 template, not in the specialization. */
2691 tpd2.current_arg = i;
2692 tpd2.arg_uses_template_parms[i] = 0;
2693 memset (tpd2.parms, 0, sizeof (int) * nargs);
2694 for_each_template_parm (type,
2695 &mark_template_parm,
2699 if (tpd2.arg_uses_template_parms [i])
2701 /* The type depended on some template parameters.
2702 If they are fully specialized in the
2703 specialization, that's OK. */
2705 for (j = 0; j < nargs; ++j)
2706 if (tpd2.parms[j] != 0
2707 && tpd.arg_uses_template_parms [j])
2709 error ("type %qT of template argument %qE depends "
2710 "on template parameter(s)",
2720 if (retrieve_specialization (maintmpl, specargs,
2721 /*class_specializations_p=*/true))
2722 /* We've already got this specialization. */
2725 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2726 = tree_cons (inner_args, inner_parms,
2727 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2728 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2732 /* Check that a template declaration's use of default arguments is not
2733 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2734 nonzero if DECL is the thing declared by a primary template.
2735 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2738 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2741 int last_level_to_check;
2746 A default template-argument shall not be specified in a
2747 function template declaration or a function template definition, nor
2748 in the template-parameter-list of the definition of a member of a
2751 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2752 /* You can't have a function template declaration in a local
2753 scope, nor you can you define a member of a class template in a
2757 if (current_class_type
2758 && !TYPE_BEING_DEFINED (current_class_type)
2759 && DECL_LANG_SPECIFIC (decl)
2760 /* If this is either a friend defined in the scope of the class
2761 or a member function. */
2762 && (DECL_FUNCTION_MEMBER_P (decl)
2763 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2764 : DECL_FRIEND_CONTEXT (decl)
2765 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2767 /* And, if it was a member function, it really was defined in
2768 the scope of the class. */
2769 && (!DECL_FUNCTION_MEMBER_P (decl)
2770 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2771 /* We already checked these parameters when the template was
2772 declared, so there's no need to do it again now. This function
2773 was defined in class scope, but we're processing it's body now
2774 that the class is complete. */
2779 If a template-parameter has a default template-argument, all
2780 subsequent template-parameters shall have a default
2781 template-argument supplied. */
2782 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2784 tree inner_parms = TREE_VALUE (parm_level);
2785 int ntparms = TREE_VEC_LENGTH (inner_parms);
2786 int seen_def_arg_p = 0;
2789 for (i = 0; i < ntparms; ++i)
2791 tree parm = TREE_VEC_ELT (inner_parms, i);
2792 if (TREE_PURPOSE (parm))
2794 else if (seen_def_arg_p)
2796 error ("no default argument for %qD", TREE_VALUE (parm));
2797 /* For better subsequent error-recovery, we indicate that
2798 there should have been a default argument. */
2799 TREE_PURPOSE (parm) = error_mark_node;
2804 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2805 /* For an ordinary class template, default template arguments are
2806 allowed at the innermost level, e.g.:
2807 template <class T = int>
2809 but, in a partial specialization, they're not allowed even
2810 there, as we have in [temp.class.spec]:
2812 The template parameter list of a specialization shall not
2813 contain default template argument values.
2815 So, for a partial specialization, or for a function template,
2816 we look at all of them. */
2819 /* But, for a primary class template that is not a partial
2820 specialization we look at all template parameters except the
2822 parms = TREE_CHAIN (parms);
2824 /* Figure out what error message to issue. */
2825 if (TREE_CODE (decl) == FUNCTION_DECL)
2826 msg = "default template arguments may not be used in function templates";
2827 else if (is_partial)
2828 msg = "default template arguments may not be used in partial specializations";
2830 msg = "default argument for template parameter for class enclosing %qD";
2832 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2833 /* If we're inside a class definition, there's no need to
2834 examine the parameters to the class itself. On the one
2835 hand, they will be checked when the class is defined, and,
2836 on the other, default arguments are valid in things like:
2837 template <class T = double>
2838 struct S { template <class U> void f(U); };
2839 Here the default argument for `S' has no bearing on the
2840 declaration of `f'. */
2841 last_level_to_check = template_class_depth (current_class_type) + 1;
2843 /* Check everything. */
2844 last_level_to_check = 0;
2846 for (parm_level = parms;
2847 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2848 parm_level = TREE_CHAIN (parm_level))
2850 tree inner_parms = TREE_VALUE (parm_level);
2854 ntparms = TREE_VEC_LENGTH (inner_parms);
2855 for (i = 0; i < ntparms; ++i)
2856 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2864 /* Clear out the default argument so that we are not
2866 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2869 /* At this point, if we're still interested in issuing messages,
2870 they must apply to classes surrounding the object declared. */
2872 msg = "default argument for template parameter for class enclosing %qD";
2876 /* Worker for push_template_decl_real, called via
2877 for_each_template_parm. DATA is really an int, indicating the
2878 level of the parameters we are interested in. If T is a template
2879 parameter of that level, return nonzero. */
2882 template_parm_this_level_p (tree t, void* data)
2884 int this_level = *(int *)data;
2887 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2888 level = TEMPLATE_PARM_LEVEL (t);
2890 level = TEMPLATE_TYPE_LEVEL (t);
2891 return level == this_level;
2894 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2895 parameters given by current_template_args, or reuses a
2896 previously existing one, if appropriate. Returns the DECL, or an
2897 equivalent one, if it is replaced via a call to duplicate_decls.
2899 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2902 push_template_decl_real (tree decl, int is_friend)
2910 int new_template_p = 0;
2911 /* True if the template is a member template, in the sense of
2913 bool member_template_p = false;
2915 if (decl == error_mark_node)
2918 /* See if this is a partial specialization. */
2919 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2920 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2921 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2923 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2926 /* For a friend, we want the context of the friend function, not
2927 the type of which it is a friend. */
2928 ctx = DECL_CONTEXT (decl);
2929 else if (CP_DECL_CONTEXT (decl)
2930 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2931 /* In the case of a virtual function, we want the class in which
2933 ctx = CP_DECL_CONTEXT (decl);
2935 /* Otherwise, if we're currently defining some class, the DECL
2936 is assumed to be a member of the class. */
2937 ctx = current_scope ();
2939 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2942 if (!DECL_CONTEXT (decl))
2943 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2945 /* See if this is a primary template. */
2946 primary = template_parm_scope_p ();
2950 if (DECL_CLASS_SCOPE_P (decl))
2951 member_template_p = true;
2952 if (current_lang_name == lang_name_c)
2953 error ("template with C linkage");
2954 else if (TREE_CODE (decl) == TYPE_DECL
2955 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2956 error ("template class without a name");
2957 else if (TREE_CODE (decl) == FUNCTION_DECL)
2959 if (DECL_DESTRUCTOR_P (decl))
2963 A destructor shall not be a member template. */
2964 error ("destructor %qD declared as member template", decl);
2965 return error_mark_node;
2967 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2968 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2969 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2970 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2971 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2972 == void_list_node)))
2974 /* [basic.stc.dynamic.allocation]
2976 An allocation function can be a function
2977 template. ... Template allocation functions shall
2978 have two or more parameters. */
2979 error ("invalid template declaration of %qD", decl);
2983 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2984 && CLASS_TYPE_P (TREE_TYPE (decl)))
2985 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx)))
2989 error ("template declaration of %q#D", decl);
2990 return error_mark_node;
2994 /* Check to see that the rules regarding the use of default
2995 arguments are not being violated. */
2996 check_default_tmpl_args (decl, current_template_parms,
2997 primary, is_partial);
3000 return process_partial_specialization (decl);
3002 args = current_template_args ();
3005 || TREE_CODE (ctx) == FUNCTION_DECL
3006 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3007 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3009 if (DECL_LANG_SPECIFIC (decl)
3010 && DECL_TEMPLATE_INFO (decl)
3011 && DECL_TI_TEMPLATE (decl))
3012 tmpl = DECL_TI_TEMPLATE (decl);
3013 /* If DECL is a TYPE_DECL for a class-template, then there won't
3014 be DECL_LANG_SPECIFIC. The information equivalent to
3015 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3016 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3017 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3018 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3020 /* Since a template declaration already existed for this
3021 class-type, we must be redeclaring it here. Make sure
3022 that the redeclaration is valid. */
3023 redeclare_class_template (TREE_TYPE (decl),
3024 current_template_parms);
3025 /* We don't need to create a new TEMPLATE_DECL; just use the
3026 one we already had. */
3027 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3031 tmpl = build_template_decl (decl, current_template_parms,
3035 if (DECL_LANG_SPECIFIC (decl)
3036 && DECL_TEMPLATE_SPECIALIZATION (decl))
3038 /* A specialization of a member template of a template
3040 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3041 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3042 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3048 tree a, t, current, parms;
3051 if (TREE_CODE (decl) == TYPE_DECL)
3053 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3054 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3055 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3056 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3057 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3060 error ("%qD does not declare a template type", decl);
3064 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3066 error ("template definition of non-template %q#D", decl);
3070 tmpl = DECL_TI_TEMPLATE (decl);
3072 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3073 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3074 && DECL_TEMPLATE_SPECIALIZATION (decl)
3075 && DECL_MEMBER_TEMPLATE_P (tmpl))
3079 /* The declaration is a specialization of a member
3080 template, declared outside the class. Therefore, the
3081 innermost template arguments will be NULL, so we
3082 replace them with the arguments determined by the
3083 earlier call to check_explicit_specialization. */
3084 args = DECL_TI_ARGS (decl);
3087 = build_template_decl (decl, current_template_parms,
3089 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3090 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3091 DECL_TI_TEMPLATE (decl) = new_tmpl;
3092 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3093 DECL_TEMPLATE_INFO (new_tmpl)
3094 = tree_cons (tmpl, args, NULL_TREE);
3096 register_specialization (new_tmpl,
3097 most_general_template (tmpl),
3102 /* Make sure the template headers we got make sense. */
3104 parms = DECL_TEMPLATE_PARMS (tmpl);
3105 i = TMPL_PARMS_DEPTH (parms);
3106 if (TMPL_ARGS_DEPTH (args) != i)
3108 error ("expected %d levels of template parms for %q#D, got %d",
3109 i, decl, TMPL_ARGS_DEPTH (args));
3112 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3114 a = TMPL_ARGS_LEVEL (args, i);
3115 t = INNERMOST_TEMPLATE_PARMS (parms);
3117 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3119 if (current == decl)
3120 error ("got %d template parameters for %q#D",
3121 TREE_VEC_LENGTH (a), decl);
3123 error ("got %d template parameters for %q#T",
3124 TREE_VEC_LENGTH (a), current);
3125 error (" but %d required", TREE_VEC_LENGTH (t));
3128 /* Perhaps we should also check that the parms are used in the
3129 appropriate qualifying scopes in the declarator? */
3131 if (current == decl)
3134 current = TYPE_CONTEXT (current);
3138 DECL_TEMPLATE_RESULT (tmpl) = decl;
3139 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3141 /* Push template declarations for global functions and types. Note
3142 that we do not try to push a global template friend declared in a
3143 template class; such a thing may well depend on the template
3144 parameters of the class. */
3145 if (new_template_p && !ctx
3146 && !(is_friend && template_class_depth (current_class_type) > 0))
3148 tmpl = pushdecl_namespace_level (tmpl);
3149 if (tmpl == error_mark_node)
3150 return error_mark_node;
3155 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3156 if (DECL_CONV_FN_P (tmpl))
3158 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3160 /* It is a conversion operator. See if the type converted to
3161 depends on innermost template operands. */
3163 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3165 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3169 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3170 back to its most general template. If TMPL is a specialization,
3171 ARGS may only have the innermost set of arguments. Add the missing
3172 argument levels if necessary. */
3173 if (DECL_TEMPLATE_INFO (tmpl))
3174 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3176 info = tree_cons (tmpl, args, NULL_TREE);
3178 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3180 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3181 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3182 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3183 /* Don't change the name if we've already set it up. */
3184 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3185 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3187 else if (DECL_LANG_SPECIFIC (decl))
3188 DECL_TEMPLATE_INFO (decl) = info;
3190 return DECL_TEMPLATE_RESULT (tmpl);
3194 push_template_decl (tree decl)
3196 return push_template_decl_real (decl, 0);
3199 /* Called when a class template TYPE is redeclared with the indicated
3200 template PARMS, e.g.:
3202 template <class T> struct S;
3203 template <class T> struct S {}; */
3206 redeclare_class_template (tree type, tree parms)
3212 if (!TYPE_TEMPLATE_INFO (type))
3214 error ("%qT is not a template type", type);
3218 tmpl = TYPE_TI_TEMPLATE (type);
3219 if (!PRIMARY_TEMPLATE_P (tmpl))
3220 /* The type is nested in some template class. Nothing to worry
3221 about here; there are no new template parameters for the nested
3225 parms = INNERMOST_TEMPLATE_PARMS (parms);
3226 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3228 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3230 cp_error_at ("previous declaration %qD", tmpl);
3231 error ("used %d template parameter%s instead of %d",
3232 TREE_VEC_LENGTH (tmpl_parms),
3233 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
3234 TREE_VEC_LENGTH (parms));
3238 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3240 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3241 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3242 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3243 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3245 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3247 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3248 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3249 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3251 cp_error_at ("template parameter %q#D", tmpl_parm);
3252 error ("redeclared here as %q#D", parm);
3256 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3258 /* We have in [temp.param]:
3260 A template-parameter may not be given default arguments
3261 by two different declarations in the same scope. */
3262 error ("redefinition of default argument for %q#D", parm);
3263 error ("%J original definition appeared here", tmpl_parm);
3267 if (parm_default != NULL_TREE)
3268 /* Update the previous template parameters (which are the ones
3269 that will really count) with the new default value. */
3270 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3271 else if (tmpl_default != NULL_TREE)
3272 /* Update the new parameters, too; they'll be used as the
3273 parameters for any members. */
3274 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3278 /* Simplify EXPR if it is a non-dependent expression. Returns the
3279 (possibly simplified) expression. */
3282 fold_non_dependent_expr (tree expr)
3284 /* If we're in a template, but EXPR isn't value dependent, simplify
3285 it. We're supposed to treat:
3287 template <typename T> void f(T[1 + 1]);
3288 template <typename T> void f(T[2]);
3290 as two declarations of the same function, for example. */
3291 if (processing_template_decl
3292 && !type_dependent_expression_p (expr)
3293 && !value_dependent_expression_p (expr))
3295 HOST_WIDE_INT saved_processing_template_decl;
3297 saved_processing_template_decl = processing_template_decl;
3298 processing_template_decl = 0;
3299 expr = tsubst_copy_and_build (expr,
3302 /*in_decl=*/NULL_TREE,
3303 /*function_p=*/false);
3304 processing_template_decl = saved_processing_template_decl;
3309 /* EXPR is an expression which is used in a constant-expression context.
3310 For instance, it could be a VAR_DECL with a constant initializer.
3311 Extract the innest constant expression.
3313 This is basically a more powerful version of decl_constant_value, which
3314 can be used also in templates where initializers can maintain a
3315 syntactic rather than semantic form (even if they are non-dependent, for
3316 access-checking purposes). */
3319 fold_decl_constant_value (tree expr)
3323 tree const_expr = decl_constant_value (expr);
3324 /* In a template, the initializer for a VAR_DECL may not be
3325 marked as TREE_CONSTANT, in which case decl_constant_value
3326 will not return the initializer. Handle that special case
3328 if (expr == const_expr
3329 && TREE_CODE (expr) == VAR_DECL
3330 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (expr)
3331 && CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (expr))
3332 /* DECL_INITIAL can be NULL if we are processing a
3333 variable initialized to an expression involving itself.
3334 We know it is initialized to a constant -- but not what
3336 && DECL_INITIAL (expr))
3337 const_expr = DECL_INITIAL (expr);
3338 if (expr == const_expr)
3340 expr = fold_non_dependent_expr (const_expr);
3346 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3347 must be a function or a pointer-to-function type, as specified
3348 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3349 and check that the resulting function has external linkage. */
3352 convert_nontype_argument_function (tree type, tree expr)
3357 fn = instantiate_type (type, fns, tf_none);
3358 if (fn == error_mark_node)
3359 return error_mark_node;
3362 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3363 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3365 /* [temp.arg.nontype]/1
3367 A template-argument for a non-type, non-template template-parameter
3370 -- the address of an object or function with external linkage. */
3371 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3373 error ("%qE is not a valid template argument for type %qT "
3374 "because function %qD has not external linkage",
3375 expr, type, fn_no_ptr);
3382 /* Attempt to convert the non-type template parameter EXPR to the
3383 indicated TYPE. If the conversion is successful, return the
3384 converted value. If the conversion is unsuccessful, return
3385 NULL_TREE if we issued an error message, or error_mark_node if we
3386 did not. We issue error messages for out-and-out bad template
3387 parameters, but not simply because the conversion failed, since we
3388 might be just trying to do argument deduction. Both TYPE and EXPR
3389 must be non-dependent.
3391 The conversion follows the special rules described in
3392 [temp.arg.nontype], and it is much more strict than an implicit
3395 This function is called twice for each template argument (see
3396 lookup_template_class for a more accurate description of this
3397 problem). This means that we need to handle expressions which
3398 are not valid in a C++ source, but can be created from the
3399 first call (for instance, casts to perform conversions). These
3400 hacks can go away after we fix the double coercion problem. */
3403 convert_nontype_argument (tree type, tree expr)
3407 /* Detect immediately string literals as invalid non-type argument.
3408 This special-case is not needed for correctness (we would easily
3409 catch this later), but only to provide better diagnostic for this
3410 common user mistake. As suggested by DR 100, we do not mention
3411 linkage issues in the diagnostic as this is not the point. */
3412 if (TREE_CODE (expr) == STRING_CST)
3414 error ("%qE is not a valid template argument for type %qT "
3415 "because string literals can never be used in this context",
3420 /* If we are in a template, EXPR may be non-dependent, but still
3421 have a syntactic, rather than semantic, form. For example, EXPR
3422 might be a SCOPE_REF, rather than the VAR_DECL to which the
3423 SCOPE_REF refers. Preserving the qualifying scope is necessary
3424 so that access checking can be performed when the template is
3425 instantiated -- but here we need the resolved form so that we can
3426 convert the argument. */
3427 expr = fold_non_dependent_expr (expr);
3428 expr_type = TREE_TYPE (expr);
3430 /* HACK: Due to double coercion, we can get a
3431 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3432 which is the tree that we built on the first call (see
3433 below when coercing to reference to object or to reference to
3434 function). We just strip everything and get to the arg.
3435 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3437 if (TREE_CODE (expr) == NOP_EXPR)
3439 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3441 /* ??? Maybe we could use convert_from_reference here, but we
3442 would need to relax its constraints because the NOP_EXPR
3443 could actually change the type to something more cv-qualified,
3444 and this is not folded by convert_from_reference. */
3445 tree addr = TREE_OPERAND (expr, 0);
3446 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3447 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3448 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3449 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3450 (TREE_TYPE (expr_type),
3451 TREE_TYPE (TREE_TYPE (addr))));
3453 expr = TREE_OPERAND (addr, 0);
3454 expr_type = TREE_TYPE (expr);
3457 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3458 parameter is a pointer to object, through decay and
3459 qualification conversion. Let's strip everything. */
3460 else if (TYPE_PTROBV_P (type))
3463 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3464 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3465 /* Skip the ADDR_EXPR only if it is part of the decay for
3466 an array. Otherwise, it is part of the original argument
3467 in the source code. */
3468 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3469 expr = TREE_OPERAND (expr, 0);
3470 expr_type = TREE_TYPE (expr);
3474 /* [temp.arg.nontype]/5, bullet 1
3476 For a non-type template-parameter of integral or enumeration type,
3477 integral promotions (_conv.prom_) and integral conversions
3478 (_conv.integral_) are applied. */
3479 if (INTEGRAL_TYPE_P (type))
3481 if (!INTEGRAL_TYPE_P (expr_type))
3482 return error_mark_node;
3484 expr = fold_decl_constant_value (expr);
3485 /* Notice that there are constant expressions like '4 % 0' which
3486 do not fold into integer constants. */
3487 if (TREE_CODE (expr) != INTEGER_CST)
3489 error ("%qE is not a valid template argument for type %qT "
3490 "because it is a non-constant expression", expr, type);
3494 /* At this point, an implicit conversion does what we want,
3495 because we already know that the expression is of integral
3497 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3498 if (expr == error_mark_node)
3499 return error_mark_node;
3501 /* Conversion was allowed: fold it to a bare integer constant. */
3504 /* [temp.arg.nontype]/5, bullet 2
3506 For a non-type template-parameter of type pointer to object,
3507 qualification conversions (_conv.qual_) and the array-to-pointer
3508 conversion (_conv.array_) are applied. */
3509 else if (TYPE_PTROBV_P (type))
3511 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3513 A template-argument for a non-type, non-template template-parameter
3514 shall be one of: [...]
3516 -- the name of a non-type template-parameter;
3517 -- the address of an object or function with external linkage, [...]
3518 expressed as "& id-expression" where the & is optional if the name
3519 refers to a function or array, or if the corresponding
3520 template-parameter is a reference.
3522 Here, we do not care about functions, as they are invalid anyway
3523 for a parameter of type pointer-to-object. */
3524 bool constant_address_p =
3525 (TREE_CODE (expr) == ADDR_EXPR
3526 || TREE_CODE (expr_type) == ARRAY_TYPE
3527 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3529 expr = decay_conversion (expr);
3530 if (expr == error_mark_node)
3531 return error_mark_node;
3533 expr = perform_qualification_conversions (type, expr);
3534 if (expr == error_mark_node)
3535 return error_mark_node;
3537 if (!constant_address_p)
3539 error ("%qE is not a valid template argument for type %qT "
3540 "because it is not a constant pointer", expr, type);
3544 /* [temp.arg.nontype]/5, bullet 3
3546 For a non-type template-parameter of type reference to object, no
3547 conversions apply. The type referred to by the reference may be more
3548 cv-qualified than the (otherwise identical) type of the
3549 template-argument. The template-parameter is bound directly to the
3550 template-argument, which must be an lvalue. */
3551 else if (TYPE_REF_OBJ_P (type))
3553 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3555 return error_mark_node;
3557 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3559 error ("%qE is not a valid template argument for type %qT "
3560 "because of conflicts in cv-qualification", expr, type);
3564 if (!real_lvalue_p (expr))
3566 error ("%qE is not a valid template argument for type %qT "
3567 "because it is not a lvalue", expr, type);
3571 /* [temp.arg.nontype]/1
3573 A template-argument for a non-type, non-template template-parameter
3574 shall be one of: [...]
3576 -- the address of an object or function with external linkage. */
3577 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3579 error ("%qE is not a valid template argument for type %qT "
3580 "because object %qD has not external linkage",
3585 expr = build_nop (type, build_address (expr));
3587 /* [temp.arg.nontype]/5, bullet 4
3589 For a non-type template-parameter of type pointer to function, only
3590 the function-to-pointer conversion (_conv.func_) is applied. If the
3591 template-argument represents a set of overloaded functions (or a
3592 pointer to such), the matching function is selected from the set
3594 else if (TYPE_PTRFN_P (type))
3596 /* If the argument is a template-id, we might not have enough
3597 context information to decay the pointer.
3598 ??? Why static5.C requires decay and subst1.C works fine
3600 if (!type_unknown_p (expr_type))
3602 expr = decay_conversion (expr);
3603 if (expr == error_mark_node)
3604 return error_mark_node;
3607 expr = convert_nontype_argument_function (type, expr);
3608 if (!expr || expr == error_mark_node)
3611 /* [temp.arg.nontype]/5, bullet 5
3613 For a non-type template-parameter of type reference to function, no
3614 conversions apply. If the template-argument represents a set of
3615 overloaded functions, the matching function is selected from the set
3617 else if (TYPE_REFFN_P (type))
3619 if (TREE_CODE (expr) == ADDR_EXPR)
3621 error ("%qE is not a valid template argument for type %qT "
3622 "because it is a pointer", expr, type);
3623 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3627 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3628 if (!expr || expr == error_mark_node)
3631 expr = build_nop(type, build_address (expr));
3633 /* [temp.arg.nontype]/5, bullet 6
3635 For a non-type template-parameter of type pointer to member function,
3636 no conversions apply. If the template-argument represents a set of
3637 overloaded member functions, the matching member function is selected
3638 from the set (_over.over_). */
3639 else if (TYPE_PTRMEMFUNC_P (type))
3641 expr = instantiate_type (type, expr, tf_none);
3642 if (expr == error_mark_node)
3643 return error_mark_node;
3645 /* There is no way to disable standard conversions in
3646 resolve_address_of_overloaded_function (called by
3647 instantiate_type). It is possible that the call succeeded by
3648 converting &B::I to &D::I (where B is a base of D), so we need
3649 to reject this conversion here.
3651 Actually, even if there was a way to disable standard conversions,
3652 it would still be better to reject them here so that we can
3653 provide a superior diagnostic. */
3654 if (!same_type_p (TREE_TYPE (expr), type))
3656 /* Make sure we are just one standard conversion off. */
3657 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3658 error ("%qE is not a valid template argument for type %qT "
3659 "because it is of type %qT", expr, type,
3661 inform ("standard conversions are not allowed in this context");
3665 /* [temp.arg.nontype]/5, bullet 7
3667 For a non-type template-parameter of type pointer to data member,
3668 qualification conversions (_conv.qual_) are applied. */
3669 else if (TYPE_PTRMEM_P (type))
3671 expr = perform_qualification_conversions (type, expr);
3672 if (expr == error_mark_node)
3675 /* A template non-type parameter must be one of the above. */
3679 /* Sanity check: did we actually convert the argument to the
3681 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3686 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3687 template template parameters. Both PARM_PARMS and ARG_PARMS are
3688 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3691 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3692 the case, then extra parameters must have default arguments.
3694 Consider the example:
3695 template <class T, class Allocator = allocator> class vector;
3696 template<template <class U> class TT> class C;
3698 C<vector> is a valid instantiation. PARM_PARMS for the above code
3699 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3700 T and Allocator) and OUTER_ARGS contains the argument that is used to
3701 substitute the TT parameter. */
3704 coerce_template_template_parms (tree parm_parms,
3706 tsubst_flags_t complain,
3710 int nparms, nargs, i;
3713 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3714 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3716 nparms = TREE_VEC_LENGTH (parm_parms);
3717 nargs = TREE_VEC_LENGTH (arg_parms);
3719 /* The rule here is opposite of coerce_template_parms. */
3722 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3725 for (i = 0; i < nparms; ++i)
3727 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3728 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3730 if (arg == NULL_TREE || arg == error_mark_node
3731 || parm == NULL_TREE || parm == error_mark_node)
3734 if (TREE_CODE (arg) != TREE_CODE (parm))
3737 switch (TREE_CODE (parm))
3743 /* We encounter instantiations of templates like
3744 template <template <template <class> class> class TT>
3747 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3748 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3750 if (!coerce_template_template_parms
3751 (parmparm, argparm, complain, in_decl, outer_args))
3757 /* The tsubst call is used to handle cases such as
3759 template <int> class C {};
3760 template <class T, template <T> class TT> class D {};
3763 i.e. the parameter list of TT depends on earlier parameters. */
3764 if (!dependent_type_p (TREE_TYPE (arg))
3766 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3778 /* Convert the indicated template ARG as necessary to match the
3779 indicated template PARM. Returns the converted ARG, or
3780 error_mark_node if the conversion was unsuccessful. Error and
3781 warning messages are issued under control of COMPLAIN. This
3782 conversion is for the Ith parameter in the parameter list. ARGS is
3783 the full set of template arguments deduced so far. */
3786 convert_template_argument (tree parm,
3789 tsubst_flags_t complain,
3795 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3797 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3799 if (TREE_CODE (arg) == TREE_LIST
3800 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3802 /* The template argument was the name of some
3803 member function. That's usually
3804 invalid, but static members are OK. In any
3805 case, grab the underlying fields/functions
3806 and issue an error later if required. */
3807 arg = TREE_VALUE (arg);
3808 TREE_TYPE (arg) = unknown_type_node;
3811 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3812 requires_type = (TREE_CODE (parm) == TYPE_DECL
3813 || requires_tmpl_type);
3815 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3816 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3817 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3818 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3821 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3822 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3823 arg = TYPE_STUB_DECL (arg);
3825 is_type = TYPE_P (arg) || is_tmpl_type;
3827 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3828 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3830 pedwarn ("to refer to a type member of a template parameter, "
3831 "use %<typename %E%>", arg);
3833 arg = make_typename_type (TREE_OPERAND (arg, 0),
3834 TREE_OPERAND (arg, 1),
3836 complain & tf_error);
3839 if (is_type != requires_type)
3843 if (complain & tf_error)
3845 error ("type/value mismatch at argument %d in template "
3846 "parameter list for %qD",
3849 error (" expected a constant of type %qT, got %qT",
3851 (is_tmpl_type ? DECL_NAME (arg) : arg));
3852 else if (requires_tmpl_type)
3853 error (" expected a class template, got %qE", arg);
3855 error (" expected a type, got %qE", arg);
3858 return error_mark_node;
3860 if (is_tmpl_type ^ requires_tmpl_type)
3862 if (in_decl && (complain & tf_error))
3864 error ("type/value mismatch at argument %d in template "
3865 "parameter list for %qD",
3868 error (" expected a type, got %qT", DECL_NAME (arg));
3870 error (" expected a class template, got %qT", arg);
3872 return error_mark_node;
3877 if (requires_tmpl_type)
3879 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3880 /* The number of argument required is not known yet.
3881 Just accept it for now. */
3882 val = TREE_TYPE (arg);
3885 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3886 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3888 if (coerce_template_template_parms (parmparm, argparm,
3894 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3896 if (val != error_mark_node
3897 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3898 val = TREE_TYPE (val);
3902 if (in_decl && (complain & tf_error))
3904 error ("type/value mismatch at argument %d in "
3905 "template parameter list for %qD",
3907 error (" expected a template of type %qD, got %qD",
3911 val = error_mark_node;
3920 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3922 if (invalid_nontype_parm_type_p (t, complain))
3923 return error_mark_node;
3925 if (!uses_template_parms (arg) && !uses_template_parms (t))
3926 /* We used to call digest_init here. However, digest_init
3927 will report errors, which we don't want when complain
3928 is zero. More importantly, digest_init will try too
3929 hard to convert things: for example, `0' should not be
3930 converted to pointer type at this point according to
3931 the standard. Accepting this is not merely an
3932 extension, since deciding whether or not these
3933 conversions can occur is part of determining which
3934 function template to call, or whether a given explicit
3935 argument specification is valid. */
3936 val = convert_nontype_argument (t, arg);
3940 if (val == NULL_TREE)
3941 val = error_mark_node;
3942 else if (val == error_mark_node && (complain & tf_error))
3943 error ("could not convert template argument %qE to %qT", arg, t);
3949 /* Convert all template arguments to their appropriate types, and
3950 return a vector containing the innermost resulting template
3951 arguments. If any error occurs, return error_mark_node. Error and
3952 warning messages are issued under control of COMPLAIN.
3954 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3955 provided in ARGLIST, or else trailing parameters must have default
3956 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3957 deduction for any unspecified trailing arguments. */
3960 coerce_template_parms (tree parms,
3963 tsubst_flags_t complain,
3964 int require_all_arguments)
3966 int nparms, nargs, i, lost = 0;
3969 tree new_inner_args;
3971 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3972 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3973 nparms = TREE_VEC_LENGTH (parms);
3977 && require_all_arguments
3978 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3980 if (complain & tf_error)
3982 error ("wrong number of template arguments (%d, should be %d)",
3986 cp_error_at ("provided for %qD", in_decl);
3989 return error_mark_node;
3992 new_inner_args = make_tree_vec (nparms);
3993 new_args = add_outermost_template_args (args, new_inner_args);
3994 for (i = 0; i < nparms; i++)
3999 /* Get the Ith template parameter. */
4000 parm = TREE_VEC_ELT (parms, i);
4002 /* Calculate the Ith argument. */
4004 arg = TREE_VEC_ELT (inner_args, i);
4005 else if (require_all_arguments)
4006 /* There must be a default arg in this case. */
4007 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4013 if (arg == error_mark_node)
4015 if (complain & tf_error)
4016 error ("template argument %d is invalid", i + 1);
4019 arg = convert_template_argument (TREE_VALUE (parm),
4020 arg, new_args, complain, i,
4023 if (arg == error_mark_node)
4025 TREE_VEC_ELT (new_inner_args, i) = arg;
4029 return error_mark_node;
4031 return new_inner_args;
4034 /* Returns 1 if template args OT and NT are equivalent. */
4037 template_args_equal (tree ot, tree nt)
4042 if (TREE_CODE (nt) == TREE_VEC)
4043 /* For member templates */
4044 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4045 else if (TYPE_P (nt))
4046 return TYPE_P (ot) && same_type_p (ot, nt);
4047 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4050 return cp_tree_equal (ot, nt);
4053 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4054 of template arguments. Returns 0 otherwise. */
4057 comp_template_args (tree oldargs, tree newargs)
4061 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4064 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4066 tree nt = TREE_VEC_ELT (newargs, i);
4067 tree ot = TREE_VEC_ELT (oldargs, i);
4069 if (! template_args_equal (ot, nt))
4075 /* Given class template name and parameter list, produce a user-friendly name
4076 for the instantiation. */
4079 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4081 static struct obstack scratch_obstack;
4082 static char *scratch_firstobj;
4085 if (!scratch_firstobj)
4086 gcc_obstack_init (&scratch_obstack);
4088 obstack_free (&scratch_obstack, scratch_firstobj);
4089 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4091 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4092 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4096 nparms = TREE_VEC_LENGTH (parms);
4097 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4098 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4099 for (i = 0; i < nparms; i++)
4101 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4102 tree arg = TREE_VEC_ELT (arglist, i);
4107 if (TREE_CODE (parm) == TYPE_DECL)
4109 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4112 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4114 if (TREE_CODE (arg) == TEMPLATE_DECL)
4116 /* Already substituted with real template. Just output
4117 the template name here */
4118 tree context = DECL_CONTEXT (arg);
4121 /* The template may be defined in a namespace, or
4122 may be a member template. */
4123 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4124 || CLASS_TYPE_P (context));
4125 cat (decl_as_string (DECL_CONTEXT (arg),
4126 TFF_PLAIN_IDENTIFIER));
4129 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4132 /* Output the parameter declaration. */
4133 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4137 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4139 /* No need to check arglist against parmlist here; we did that
4140 in coerce_template_parms, called from lookup_template_class. */
4141 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4144 char *bufp = obstack_next_free (&scratch_obstack);
4146 while (bufp[offset - 1] == ' ')
4148 obstack_blank_fast (&scratch_obstack, offset);
4150 /* B<C<char> >, not B<C<char>> */
4151 if (bufp[offset - 1] == '>')
4156 return (char *) obstack_base (&scratch_obstack);
4160 classtype_mangled_name (tree t)
4162 if (CLASSTYPE_TEMPLATE_INFO (t)
4163 /* Specializations have already had their names set up in
4164 lookup_template_class. */
4165 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4167 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4169 /* For non-primary templates, the template parameters are
4170 implicit from their surrounding context. */
4171 if (PRIMARY_TEMPLATE_P (tmpl))
4173 tree name = DECL_NAME (tmpl);
4174 char *mangled_name = mangle_class_name_for_template
4175 (IDENTIFIER_POINTER (name),
4176 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4177 CLASSTYPE_TI_ARGS (t));
4178 tree id = get_identifier (mangled_name);
4179 IDENTIFIER_TEMPLATE (id) = name;
4184 return TYPE_IDENTIFIER (t);
4188 add_pending_template (tree d)
4190 tree ti = (TYPE_P (d)
4191 ? CLASSTYPE_TEMPLATE_INFO (d)
4192 : DECL_TEMPLATE_INFO (d));
4196 if (TI_PENDING_TEMPLATE_FLAG (ti))
4199 /* We are called both from instantiate_decl, where we've already had a
4200 tinst_level pushed, and instantiate_template, where we haven't.
4202 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4205 push_tinst_level (d);
4207 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4208 if (last_pending_template)
4209 TREE_CHAIN (last_pending_template) = pt;
4211 pending_templates = pt;
4213 last_pending_template = pt;
4215 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4222 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4223 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4224 documentation for TEMPLATE_ID_EXPR. */
4227 lookup_template_function (tree fns, tree arglist)
4231 if (fns == error_mark_node || arglist == error_mark_node)
4232 return error_mark_node;
4234 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4235 if (fns == NULL_TREE
4236 || TREE_CODE (fns) == FUNCTION_DECL)
4238 error ("non-template used as template");
4239 return error_mark_node;
4242 gcc_assert (TREE_CODE (fns) == TEMPLATE_DECL
4243 || TREE_CODE (fns) == OVERLOAD
4245 || TREE_CODE (fns) == IDENTIFIER_NODE);
4247 if (BASELINK_P (fns))
4249 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4251 BASELINK_FUNCTIONS (fns),
4256 type = TREE_TYPE (fns);
4257 if (TREE_CODE (fns) == OVERLOAD || !type)
4258 type = unknown_type_node;
4260 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4263 /* Within the scope of a template class S<T>, the name S gets bound
4264 (in build_self_reference) to a TYPE_DECL for the class, not a
4265 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4266 or one of its enclosing classes, and that type is a template,
4267 return the associated TEMPLATE_DECL. Otherwise, the original
4268 DECL is returned. */
4271 maybe_get_template_decl_from_type_decl (tree decl)
4273 return (decl != NULL_TREE
4274 && TREE_CODE (decl) == TYPE_DECL
4275 && DECL_ARTIFICIAL (decl)
4276 && CLASS_TYPE_P (TREE_TYPE (decl))
4277 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4278 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4281 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4282 parameters, find the desired type.
4284 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4286 IN_DECL, if non-NULL, is the template declaration we are trying to
4289 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4290 the class we are looking up.
4292 Issue error and warning messages under control of COMPLAIN.
4294 If the template class is really a local class in a template
4295 function, then the FUNCTION_CONTEXT is the function in which it is
4298 ??? Note that this function is currently called *twice* for each
4299 template-id: the first time from the parser, while creating the
4300 incomplete type (finish_template_type), and the second type during the
4301 real instantiation (instantiate_template_class). This is surely something
4302 that we want to avoid. It also causes some problems with argument
4303 coercion (see convert_nontype_argument for more information on this). */
4306 lookup_template_class (tree d1,
4311 tsubst_flags_t complain)
4313 tree template = NULL_TREE, parmlist;
4316 timevar_push (TV_NAME_LOOKUP);
4318 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4320 tree value = innermost_non_namespace_value (d1);
4321 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4326 push_decl_namespace (context);
4327 template = lookup_name (d1, /*prefer_type=*/0);
4328 template = maybe_get_template_decl_from_type_decl (template);
4330 pop_decl_namespace ();
4333 context = DECL_CONTEXT (template);
4335 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4337 tree type = TREE_TYPE (d1);
4339 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4340 an implicit typename for the second A. Deal with it. */
4341 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4342 type = TREE_TYPE (type);
4344 if (CLASSTYPE_TEMPLATE_INFO (type))
4346 template = CLASSTYPE_TI_TEMPLATE (type);
4347 d1 = DECL_NAME (template);
4350 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4351 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4353 template = TYPE_TI_TEMPLATE (d1);
4354 d1 = DECL_NAME (template);
4356 else if (TREE_CODE (d1) == TEMPLATE_DECL
4357 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4360 d1 = DECL_NAME (template);
4361 context = DECL_CONTEXT (template);
4364 /* Issue an error message if we didn't find a template. */
4367 if (complain & tf_error)
4368 error ("%qT is not a template", d1);
4369 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4372 if (TREE_CODE (template) != TEMPLATE_DECL
4373 /* Make sure it's a user visible template, if it was named by
4375 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4376 && !PRIMARY_TEMPLATE_P (template)))
4378 if (complain & tf_error)
4380 error ("non-template type %qT used as a template", d1);
4382 cp_error_at ("for template declaration %qD", in_decl);
4384 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4387 complain &= ~tf_user;
4389 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4391 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4392 template arguments */
4397 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4399 /* Consider an example where a template template parameter declared as
4401 template <class T, class U = std::allocator<T> > class TT
4403 The template parameter level of T and U are one level larger than
4404 of TT. To proper process the default argument of U, say when an
4405 instantiation `TT<int>' is seen, we need to build the full
4406 arguments containing {int} as the innermost level. Outer levels,
4407 available when not appearing as default template argument, can be
4408 obtained from `current_template_args ()'.
4410 Suppose that TT is later substituted with std::vector. The above
4411 instantiation is `TT<int, std::allocator<T> >' with TT at
4412 level 1, and T at level 2, while the template arguments at level 1
4413 becomes {std::vector} and the inner level 2 is {int}. */
4415 if (current_template_parms)
4416 arglist = add_to_template_args (current_template_args (), arglist);
4418 arglist2 = coerce_template_parms (parmlist, arglist, template,
4419 complain, /*require_all_args=*/1);
4420 if (arglist2 == error_mark_node
4421 || (!uses_template_parms (arglist2)
4422 && check_instantiated_args (template, arglist2, complain)))
4423 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4425 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4426 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4430 tree template_type = TREE_TYPE (template);
4433 tree found = NULL_TREE;
4436 int is_partial_instantiation;
4438 gen_tmpl = most_general_template (template);
4439 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4440 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4441 arg_depth = TMPL_ARGS_DEPTH (arglist);
4443 if (arg_depth == 1 && parm_depth > 1)
4445 /* We've been given an incomplete set of template arguments.
4448 template <class T> struct S1 {
4449 template <class U> struct S2 {};
4450 template <class U> struct S2<U*> {};
4453 we will be called with an ARGLIST of `U*', but the
4454 TEMPLATE will be `template <class T> template
4455 <class U> struct S1<T>::S2'. We must fill in the missing
4458 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4460 arg_depth = TMPL_ARGS_DEPTH (arglist);
4463 /* Now we should have enough arguments. */
4464 gcc_assert (parm_depth == arg_depth);
4466 /* From here on, we're only interested in the most general
4468 template = gen_tmpl;
4470 /* Calculate the BOUND_ARGS. These will be the args that are
4471 actually tsubst'd into the definition to create the
4475 /* We have multiple levels of arguments to coerce, at once. */
4477 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4479 tree bound_args = make_tree_vec (parm_depth);
4481 for (i = saved_depth,
4482 t = DECL_TEMPLATE_PARMS (template);
4483 i > 0 && t != NULL_TREE;
4484 --i, t = TREE_CHAIN (t))
4486 tree a = coerce_template_parms (TREE_VALUE (t),
4488 complain, /*require_all_args=*/1);
4490 /* Don't process further if one of the levels fails. */
4491 if (a == error_mark_node)
4493 /* Restore the ARGLIST to its full size. */
4494 TREE_VEC_LENGTH (arglist) = saved_depth;
4495 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4498 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4500 /* We temporarily reduce the length of the ARGLIST so
4501 that coerce_template_parms will see only the arguments
4502 corresponding to the template parameters it is
4504 TREE_VEC_LENGTH (arglist)--;
4507 /* Restore the ARGLIST to its full size. */
4508 TREE_VEC_LENGTH (arglist) = saved_depth;
4510 arglist = bound_args;
4514 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4515 INNERMOST_TEMPLATE_ARGS (arglist),
4517 complain, /*require_all_args=*/1);
4519 if (arglist == error_mark_node)
4520 /* We were unable to bind the arguments. */
4521 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4523 /* In the scope of a template class, explicit references to the
4524 template class refer to the type of the template, not any
4525 instantiation of it. For example, in:
4527 template <class T> class C { void f(C<T>); }
4529 the `C<T>' is just the same as `C'. Outside of the
4530 class, however, such a reference is an instantiation. */
4531 if (comp_template_args (TYPE_TI_ARGS (template_type),
4534 found = template_type;
4536 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4540 for (ctx = current_class_type;
4541 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4543 ? TYPE_CONTEXT (ctx)
4544 : DECL_CONTEXT (ctx)))
4545 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4548 /* We're not in the scope of the class, so the
4549 TEMPLATE_TYPE is not the type we want after all. */
4555 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4557 /* If we already have this specialization, return it. */
4558 found = retrieve_specialization (template, arglist,
4559 /*class_specializations_p=*/false);
4561 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4563 /* This type is a "partial instantiation" if any of the template
4564 arguments still involve template parameters. Note that we set
4565 IS_PARTIAL_INSTANTIATION for partial specializations as
4567 is_partial_instantiation = uses_template_parms (arglist);
4569 /* If the deduced arguments are invalid, then the binding
4571 if (!is_partial_instantiation
4572 && check_instantiated_args (template,
4573 INNERMOST_TEMPLATE_ARGS (arglist),
4575 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4577 if (!is_partial_instantiation
4578 && !PRIMARY_TEMPLATE_P (template)
4579 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4581 found = xref_tag_from_type (TREE_TYPE (template),
4582 DECL_NAME (template),
4583 /*tag_scope=*/ts_global);
4584 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4587 context = tsubst (DECL_CONTEXT (template), arglist,
4590 context = global_namespace;
4592 /* Create the type. */
4593 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4595 if (!is_partial_instantiation)
4597 set_current_access_from_decl (TYPE_NAME (template_type));
4598 t = start_enum (TYPE_IDENTIFIER (template_type));
4601 /* We don't want to call start_enum for this type, since
4602 the values for the enumeration constants may involve
4603 template parameters. And, no one should be interested
4604 in the enumeration constants for such a type. */
4605 t = make_node (ENUMERAL_TYPE);
4609 t = make_aggr_type (TREE_CODE (template_type));
4610 CLASSTYPE_DECLARED_CLASS (t)
4611 = CLASSTYPE_DECLARED_CLASS (template_type);
4612 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4613 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4615 /* A local class. Make sure the decl gets registered properly. */
4616 if (context == current_function_decl)
4617 pushtag (DECL_NAME (template), t, 0);
4620 /* If we called start_enum or pushtag above, this information
4621 will already be set up. */
4624 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4626 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4627 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4628 TYPE_STUB_DECL (t) = type_decl;
4629 DECL_SOURCE_LOCATION (type_decl)
4630 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4633 type_decl = TYPE_NAME (t);
4635 TREE_PRIVATE (type_decl)
4636 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4637 TREE_PROTECTED (type_decl)
4638 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4640 /* Set up the template information. We have to figure out which
4641 template is the immediate parent if this is a full
4643 if (parm_depth == 1 || is_partial_instantiation
4644 || !PRIMARY_TEMPLATE_P (template))
4645 /* This case is easy; there are no member templates involved. */
4649 /* This is a full instantiation of a member template. Look
4650 for a partial instantiation of which this is an instance. */
4652 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4653 found; found = TREE_CHAIN (found))
4656 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4658 /* We only want partial instantiations, here, not
4659 specializations or full instantiations. */
4660 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4661 || !uses_template_parms (TREE_VALUE (found)))
4664 /* Temporarily reduce by one the number of levels in the
4665 ARGLIST and in FOUND so as to avoid comparing the
4666 last set of arguments. */
4667 TREE_VEC_LENGTH (arglist)--;
4668 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4670 /* See if the arguments match. If they do, then TMPL is
4671 the partial instantiation we want. */
4672 success = comp_template_args (TREE_PURPOSE (found), arglist);
4674 /* Restore the argument vectors to their full size. */
4675 TREE_VEC_LENGTH (arglist)++;
4676 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4687 /* There was no partial instantiation. This happens
4688 where C<T> is a member template of A<T> and it's used
4691 template <typename T> struct B { A<T>::C<int> m; };
4694 Create the partial instantiation.
4696 TREE_VEC_LENGTH (arglist)--;
4697 found = tsubst (template, arglist, complain, NULL_TREE);
4698 TREE_VEC_LENGTH (arglist)++;
4702 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4703 DECL_TEMPLATE_INSTANTIATIONS (template)
4704 = tree_cons (arglist, t,
4705 DECL_TEMPLATE_INSTANTIATIONS (template));
4707 if (TREE_CODE (t) == ENUMERAL_TYPE
4708 && !is_partial_instantiation)
4709 /* Now that the type has been registered on the instantiations
4710 list, we set up the enumerators. Because the enumeration
4711 constants may involve the enumeration type itself, we make
4712 sure to register the type first, and then create the
4713 constants. That way, doing tsubst_expr for the enumeration
4714 constants won't result in recursive calls here; we'll find
4715 the instantiation and exit above. */
4716 tsubst_enum (template_type, t, arglist);
4718 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4720 if (TREE_CODE (t) != ENUMERAL_TYPE)
4721 DECL_NAME (type_decl) = classtype_mangled_name (t);
4722 if (is_partial_instantiation)
4723 /* If the type makes use of template parameters, the
4724 code that generates debugging information will crash. */
4725 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4727 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4729 timevar_pop (TV_NAME_LOOKUP);
4736 struct pointer_set_t *visited;
4739 /* Called from for_each_template_parm via walk_tree. */
4742 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4745 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4746 tree_fn_t fn = pfd->fn;
4747 void *data = pfd->data;
4750 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4751 return error_mark_node;
4753 switch (TREE_CODE (t))
4756 if (TYPE_PTRMEMFUNC_P (t))
4762 if (!TYPE_TEMPLATE_INFO (t))
4764 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4765 fn, data, pfd->visited))
4766 return error_mark_node;
4770 /* Since we're not going to walk subtrees, we have to do this
4772 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4774 return error_mark_node;
4778 /* Check the return type. */
4779 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4780 return error_mark_node;
4782 /* Check the parameter types. Since default arguments are not
4783 instantiated until they are needed, the TYPE_ARG_TYPES may
4784 contain expressions that involve template parameters. But,
4785 no-one should be looking at them yet. And, once they're
4786 instantiated, they don't contain template parameters, so
4787 there's no point in looking at them then, either. */
4791 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4792 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4794 return error_mark_node;
4796 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4797 want walk_tree walking into them itself. */
4803 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4805 return error_mark_node;
4810 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4811 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4813 return error_mark_node;
4818 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4819 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4821 return error_mark_node;
4822 if (DECL_CONTEXT (t)
4823 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4825 return error_mark_node;
4828 case BOUND_TEMPLATE_TEMPLATE_PARM:
4829 /* Record template parameters such as `T' inside `TT<T>'. */
4830 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4831 return error_mark_node;
4834 case TEMPLATE_TEMPLATE_PARM:
4835 case TEMPLATE_TYPE_PARM:
4836 case TEMPLATE_PARM_INDEX:
4837 if (fn && (*fn)(t, data))
4838 return error_mark_node;
4840 return error_mark_node;
4844 /* A template template parameter is encountered. */
4845 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4846 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4847 return error_mark_node;
4849 /* Already substituted template template parameter */
4855 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4856 data, pfd->visited))
4857 return error_mark_node;
4861 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4862 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4863 (TREE_TYPE (t)), fn, data,
4865 return error_mark_node;
4870 /* If there's no type, then this thing must be some expression
4871 involving template parameters. */
4872 if (!fn && !TREE_TYPE (t))
4873 return error_mark_node;
4878 case REINTERPRET_CAST_EXPR:
4879 case CONST_CAST_EXPR:
4880 case STATIC_CAST_EXPR:
4881 case DYNAMIC_CAST_EXPR:
4885 case PSEUDO_DTOR_EXPR:
4887 return error_mark_node;
4891 /* If we do not handle this case specially, we end up walking
4892 the BINFO hierarchy, which is circular, and therefore
4893 confuses walk_tree. */
4895 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4897 return error_mark_node;
4904 /* We didn't find any template parameters we liked. */
4908 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4909 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4910 call FN with the parameter and the DATA.
4911 If FN returns nonzero, the iteration is terminated, and
4912 for_each_template_parm returns 1. Otherwise, the iteration
4913 continues. If FN never returns a nonzero value, the value
4914 returned by for_each_template_parm is 0. If FN is NULL, it is
4915 considered to be the function which always returns 1. */
4918 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4919 struct pointer_set_t *visited)
4921 struct pair_fn_data pfd;
4928 /* Walk the tree. (Conceptually, we would like to walk without
4929 duplicates, but for_each_template_parm_r recursively calls
4930 for_each_template_parm, so we would need to reorganize a fair
4931 bit to use walk_tree_without_duplicates, so we keep our own
4934 pfd.visited = visited;
4936 pfd.visited = pointer_set_create ();
4937 result = walk_tree (&t,
4938 for_each_template_parm_r,
4940 pfd.visited) != NULL_TREE;
4945 pointer_set_destroy (pfd.visited);
4952 /* Returns true if T depends on any template parameter. */
4955 uses_template_parms (tree t)
4958 int saved_processing_template_decl;
4960 saved_processing_template_decl = processing_template_decl;
4961 if (!saved_processing_template_decl)
4962 processing_template_decl = 1;
4964 dependent_p = dependent_type_p (t);
4965 else if (TREE_CODE (t) == TREE_VEC)
4966 dependent_p = any_dependent_template_arguments_p (t);
4967 else if (TREE_CODE (t) == TREE_LIST)
4968 dependent_p = (uses_template_parms (TREE_VALUE (t))
4969 || uses_template_parms (TREE_CHAIN (t)));
4972 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4973 || TREE_CODE (t) == OVERLOAD
4974 || TREE_CODE (t) == BASELINK
4975 || CONSTANT_CLASS_P (t))
4976 dependent_p = (type_dependent_expression_p (t)
4977 || value_dependent_expression_p (t));
4980 gcc_assert (t == error_mark_node);
4981 dependent_p = false;
4984 processing_template_decl = saved_processing_template_decl;
4989 /* Returns true if T depends on any template parameter with level LEVEL. */
4992 uses_template_parms_level (tree t, int level)
4994 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4997 static int tinst_depth;
4998 extern int max_tinst_depth;
4999 #ifdef GATHER_STATISTICS
5002 static int tinst_level_tick;
5003 static int last_template_error_tick;
5005 /* We're starting to instantiate D; record the template instantiation context
5006 for diagnostics and to restore it later. */
5009 push_tinst_level (tree d)
5013 if (tinst_depth >= max_tinst_depth)
5015 /* If the instantiation in question still has unbound template parms,
5016 we don't really care if we can't instantiate it, so just return.
5017 This happens with base instantiation for implicit `typename'. */
5018 if (uses_template_parms (d))
5021 last_template_error_tick = tinst_level_tick;
5022 error ("template instantiation depth exceeds maximum of %d (use "
5023 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5024 max_tinst_depth, d);
5026 print_instantiation_context ();
5031 new = make_tinst_level (d, input_location);
5032 TREE_CHAIN (new) = current_tinst_level;
5033 current_tinst_level = new;
5036 #ifdef GATHER_STATISTICS
5037 if (tinst_depth > depth_reached)
5038 depth_reached = tinst_depth;
5045 /* We're done instantiating this template; return to the instantiation
5049 pop_tinst_level (void)
5051 tree old = current_tinst_level;
5053 /* Restore the filename and line number stashed away when we started
5054 this instantiation. */
5055 input_location = TINST_LOCATION (old);
5056 current_tinst_level = TREE_CHAIN (old);
5061 /* We're instantiating a deferred template; restore the template
5062 instantiation context in which the instantiation was requested, which
5063 is one step out from LEVEL. */
5066 reopen_tinst_level (tree level)
5071 for (t = level; t; t = TREE_CHAIN (t))
5074 current_tinst_level = level;
5078 /* Return the outermost template instantiation context, for use with
5079 -falt-external-templates. */
5082 tinst_for_decl (void)
5084 tree p = current_tinst_level;
5087 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
5092 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5093 vector of template arguments, as for tsubst.
5095 Returns an appropriate tsubst'd friend declaration. */
5098 tsubst_friend_function (tree decl, tree args)
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 substitution -- 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,
5796 /*tag_scope=*/ts_global);
5797 pop_nested_namespace (ns);
5800 if (adjust_processing_template_decl)
5801 /* Trick make_friend_class into realizing that the friend
5802 we're adding is a template, not an ordinary class. It's
5803 important that we use make_friend_class since it will
5804 perform some error-checking and output cross-reference
5806 ++processing_template_decl;
5808 if (friend_type != error_mark_node)
5809 make_friend_class (type, friend_type, /*complain=*/false);
5811 if (adjust_processing_template_decl)
5812 --processing_template_decl;
5816 /* Build new DECL_FRIENDLIST. */
5819 if (TREE_CODE (t) == TEMPLATE_DECL)
5821 ++processing_template_decl;
5822 push_deferring_access_checks (dk_no_check);
5825 r = tsubst_friend_function (t, args);
5826 add_friend (type, r, /*complain=*/false);
5827 if (TREE_CODE (t) == TEMPLATE_DECL)
5829 pop_deferring_access_checks ();
5830 --processing_template_decl;
5836 /* Set the file and line number information to whatever is given for
5837 the class itself. This puts error messages involving generated
5838 implicit functions at a predictable point, and the same point
5839 that would be used for non-template classes. */
5840 typedecl = TYPE_MAIN_DECL (type);
5841 input_location = DECL_SOURCE_LOCATION (typedecl);
5843 unreverse_member_declarations (type);
5844 finish_struct_1 (type);
5845 TYPE_BEING_DEFINED (type) = 0;
5847 /* Now that the class is complete, instantiate default arguments for
5848 any member functions. We don't do this earlier because the
5849 default arguments may reference members of the class. */
5850 if (!PRIMARY_TEMPLATE_P (template))
5851 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5852 if (TREE_CODE (t) == FUNCTION_DECL
5853 /* Implicitly generated member functions will not have template
5854 information; they are not instantiations, but instead are
5855 created "fresh" for each instantiation. */
5856 && DECL_TEMPLATE_INFO (t))
5857 tsubst_default_arguments (t);
5860 pop_from_top_level ();
5861 pop_deferring_access_checks ();
5864 /* The vtable for a template class can be emitted in any translation
5865 unit in which the class is instantiated. When there is no key
5866 method, however, finish_struct_1 will already have added TYPE to
5867 the keyed_classes list. */
5868 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5869 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5875 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5881 else if (TYPE_P (t))
5882 r = tsubst (t, args, complain, in_decl);
5885 r = tsubst_expr (t, args, complain, in_decl);
5887 if (!uses_template_parms (r))
5889 /* Sometimes, one of the args was an expression involving a
5890 template constant parameter, like N - 1. Now that we've
5891 tsubst'd, we might have something like 2 - 1. This will
5892 confuse lookup_template_class, so we do constant folding
5893 here. We have to unset processing_template_decl, to fool
5894 tsubst_copy_and_build() into building an actual tree. */
5896 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5897 as simple as it's going to get, and trying to reprocess
5898 the trees will break. Once tsubst_expr et al DTRT for
5899 non-dependent exprs, this code can go away, as the type
5900 will always be set. */
5903 int saved_processing_template_decl = processing_template_decl;
5904 processing_template_decl = 0;
5905 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5906 tf_error, /*in_decl=*/NULL_TREE,
5907 /*function_p=*/false);
5908 processing_template_decl = saved_processing_template_decl;
5916 /* Substitute ARGS into the vector or list of template arguments T. */
5919 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5921 int len = TREE_VEC_LENGTH (t);
5922 int need_new = 0, i;
5923 tree *elts = alloca (len * sizeof (tree));
5925 for (i = 0; i < len; i++)
5927 tree orig_arg = TREE_VEC_ELT (t, i);
5930 if (TREE_CODE (orig_arg) == TREE_VEC)
5931 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5933 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5935 if (new_arg == error_mark_node)
5936 return error_mark_node;
5939 if (new_arg != orig_arg)
5946 t = make_tree_vec (len);
5947 for (i = 0; i < len; i++)
5948 TREE_VEC_ELT (t, i) = elts[i];
5953 /* Return the result of substituting ARGS into the template parameters
5954 given by PARMS. If there are m levels of ARGS and m + n levels of
5955 PARMS, then the result will contain n levels of PARMS. For
5956 example, if PARMS is `template <class T> template <class U>
5957 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5958 result will be `template <int*, double, class V>'. */
5961 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5966 for (new_parms = &r;
5967 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5968 new_parms = &(TREE_CHAIN (*new_parms)),
5969 parms = TREE_CHAIN (parms))
5972 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5975 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5977 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5978 tree default_value = TREE_PURPOSE (tuple);
5979 tree parm_decl = TREE_VALUE (tuple);
5981 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5982 default_value = tsubst_template_arg (default_value, args,
5983 complain, NULL_TREE);
5985 tuple = build_tree_list (default_value, parm_decl);
5986 TREE_VEC_ELT (new_vec, i) = tuple;
5990 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
5991 - TMPL_ARGS_DEPTH (args)),
5992 new_vec, NULL_TREE);
5998 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5999 type T. If T is not an aggregate or enumeration type, it is
6000 handled as if by tsubst. IN_DECL is as for tsubst. If
6001 ENTERING_SCOPE is nonzero, T is the context for a template which
6002 we are presently tsubst'ing. Return the substituted value. */
6005 tsubst_aggr_type (tree t,
6007 tsubst_flags_t complain,
6014 switch (TREE_CODE (t))
6017 if (TYPE_PTRMEMFUNC_P (t))
6018 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6020 /* Else fall through. */
6023 if (TYPE_TEMPLATE_INFO (t))
6029 /* First, determine the context for the type we are looking
6031 context = TYPE_CONTEXT (t);
6033 context = tsubst_aggr_type (context, args, complain,
6034 in_decl, /*entering_scope=*/1);
6036 /* Then, figure out what arguments are appropriate for the
6037 type we are trying to find. For example, given:
6039 template <class T> struct S;
6040 template <class T, class U> void f(T, U) { S<U> su; }
6042 and supposing that we are instantiating f<int, double>,
6043 then our ARGS will be {int, double}, but, when looking up
6044 S we only want {double}. */
6045 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6047 if (argvec == error_mark_node)
6048 return error_mark_node;
6050 r = lookup_template_class (t, argvec, in_decl, context,
6051 entering_scope, complain);
6053 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6056 /* This is not a template type, so there's nothing to do. */
6060 return tsubst (t, args, complain, in_decl);
6064 /* Substitute into the default argument ARG (a default argument for
6065 FN), which has the indicated TYPE. */
6068 tsubst_default_argument (tree fn, tree type, tree arg)
6070 tree saved_class_ptr = NULL_TREE;
6071 tree saved_class_ref = NULL_TREE;
6073 /* This default argument came from a template. Instantiate the
6074 default argument here, not in tsubst. In the case of
6083 we must be careful to do name lookup in the scope of S<T>,
6084 rather than in the current class. */
6085 push_access_scope (fn);
6086 /* The default argument expression should not be considered to be
6087 within the scope of FN. Since push_access_scope sets
6088 current_function_decl, we must explicitly clear it here. */
6089 current_function_decl = NULL_TREE;
6090 /* The "this" pointer is not valid in a default argument. */
6093 saved_class_ptr = current_class_ptr;
6094 cp_function_chain->x_current_class_ptr = NULL_TREE;
6095 saved_class_ref = current_class_ref;
6096 cp_function_chain->x_current_class_ref = NULL_TREE;
6099 push_deferring_access_checks(dk_no_deferred);
6100 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6101 tf_error | tf_warning, NULL_TREE);
6102 pop_deferring_access_checks();
6104 /* Restore the "this" pointer. */
6107 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6108 cp_function_chain->x_current_class_ref = saved_class_ref;
6111 pop_access_scope (fn);
6113 /* Make sure the default argument is reasonable. */
6114 arg = check_default_argument (type, arg);
6119 /* Substitute into all the default arguments for FN. */
6122 tsubst_default_arguments (tree fn)
6127 tmpl_args = DECL_TI_ARGS (fn);
6129 /* If this function is not yet instantiated, we certainly don't need
6130 its default arguments. */
6131 if (uses_template_parms (tmpl_args))
6134 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6136 arg = TREE_CHAIN (arg))
6137 if (TREE_PURPOSE (arg))
6138 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6140 TREE_PURPOSE (arg));
6143 /* Substitute the ARGS into the T, which is a _DECL. Return the
6144 result of the substitution. Issue error and warning messages under
6145 control of COMPLAIN. */
6148 tsubst_decl (tree t, tree args, 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 function template,
6163 member class template, and template template parameter of
6164 a template class. */
6165 tree decl = DECL_TEMPLATE_RESULT (t);
6170 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6172 /* Template template parameter is treated here. */
6173 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6174 if (new_type == error_mark_node)
6175 return error_mark_node;
6178 TREE_CHAIN (r) = NULL_TREE;
6179 TREE_TYPE (r) = new_type;
6180 DECL_TEMPLATE_RESULT (r)
6181 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6182 DECL_TEMPLATE_PARMS (r)
6183 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6185 TYPE_NAME (new_type) = r;
6189 /* We might already have an instance of this template.
6190 The ARGS are for the surrounding class type, so the
6191 full args contain the tsubst'd args for the context,
6192 plus the innermost args from the template decl. */
6193 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6194 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6195 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6196 full_args = tsubst_template_args (tmpl_args, args,
6199 /* tsubst_template_args doesn't copy the vector if
6200 nothing changed. But, *something* should have
6202 gcc_assert (full_args != tmpl_args);
6204 spec = retrieve_specialization (t, full_args,
6205 /*class_specializations_p=*/true);
6206 if (spec != NULL_TREE)
6212 /* Make a new template decl. It will be similar to the
6213 original, but will record the current template arguments.
6214 We also create a new function declaration, which is just
6215 like the old one, but points to this new template, rather
6216 than the old one. */
6218 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6219 TREE_CHAIN (r) = NULL_TREE;
6222 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6224 /*entering_scope=*/1);
6225 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6227 if (TREE_CODE (decl) == TYPE_DECL)
6229 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6230 if (new_type == error_mark_node)
6231 return error_mark_node;
6233 TREE_TYPE (r) = new_type;
6234 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6235 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6236 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6240 tree new_decl = tsubst (decl, args, complain, in_decl);
6241 if (new_decl == error_mark_node)
6242 return error_mark_node;
6244 DECL_TEMPLATE_RESULT (r) = new_decl;
6245 DECL_TI_TEMPLATE (new_decl) = r;
6246 TREE_TYPE (r) = TREE_TYPE (new_decl);
6247 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6250 SET_DECL_IMPLICIT_INSTANTIATION (r);
6251 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6252 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6254 /* The template parameters for this new template are all the
6255 template parameters for the old template, except the
6256 outermost level of parameters. */
6257 DECL_TEMPLATE_PARMS (r)
6258 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6261 if (PRIMARY_TEMPLATE_P (t))
6262 DECL_PRIMARY_TEMPLATE (r) = r;
6264 if (TREE_CODE (decl) != TYPE_DECL)
6265 /* Record this non-type partial instantiation. */
6266 register_specialization (r, t,
6267 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6274 tree argvec = NULL_TREE;
6282 /* Nobody should be tsubst'ing into non-template functions. */
6283 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6285 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6290 /* If T is not dependent, just return it. We have to
6291 increment PROCESSING_TEMPLATE_DECL because
6292 value_dependent_expression_p assumes that nothing is
6293 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6294 ++processing_template_decl;
6295 dependent_p = value_dependent_expression_p (t);
6296 --processing_template_decl;
6300 /* Calculate the most general template of which R is a
6301 specialization, and the complete set of arguments used to
6303 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6304 argvec = tsubst_template_args (DECL_TI_ARGS
6305 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6306 args, complain, in_decl);
6308 /* Check to see if we already have this specialization. */
6309 spec = retrieve_specialization (gen_tmpl, argvec,
6310 /*class_specializations_p=*/false);
6318 /* We can see more levels of arguments than parameters if
6319 there was a specialization of a member template, like
6322 template <class T> struct S { template <class U> void f(); }
6323 template <> template <class U> void S<int>::f(U);
6325 Here, we'll be substituting into the specialization,
6326 because that's where we can find the code we actually
6327 want to generate, but we'll have enough arguments for
6328 the most general template.
6330 We also deal with the peculiar case:
6332 template <class T> struct S {
6333 template <class U> friend void f();
6335 template <class U> void f() {}
6337 template void f<double>();
6339 Here, the ARGS for the instantiation of will be {int,
6340 double}. But, we only need as many ARGS as there are
6341 levels of template parameters in CODE_PATTERN. We are
6342 careful not to get fooled into reducing the ARGS in
6345 template <class T> struct S { template <class U> void f(U); }
6346 template <class T> template <> void S<T>::f(int) {}
6348 which we can spot because the pattern will be a
6349 specialization in this case. */
6350 args_depth = TMPL_ARGS_DEPTH (args);
6352 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6353 if (args_depth > parms_depth
6354 && !DECL_TEMPLATE_SPECIALIZATION (t))
6355 args = get_innermost_template_args (args, parms_depth);
6359 /* This special case arises when we have something like this:
6361 template <class T> struct S {
6362 friend void f<int>(int, double);
6365 Here, the DECL_TI_TEMPLATE for the friend declaration
6366 will be an IDENTIFIER_NODE. We are being called from
6367 tsubst_friend_function, and we want only to create a
6368 new decl (R) with appropriate types so that we can call
6369 determine_specialization. */
6370 gen_tmpl = NULL_TREE;
6373 if (DECL_CLASS_SCOPE_P (t))
6375 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6379 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6380 complain, t, /*entering_scope=*/1);
6385 ctx = DECL_CONTEXT (t);
6387 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6388 if (type == error_mark_node)
6389 return error_mark_node;
6391 /* We do NOT check for matching decls pushed separately at this
6392 point, as they may not represent instantiations of this
6393 template, and in any case are considered separate under the
6396 DECL_USE_TEMPLATE (r) = 0;
6397 TREE_TYPE (r) = type;
6398 /* Clear out the mangled name and RTL for the instantiation. */
6399 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6400 SET_DECL_RTL (r, NULL_RTX);
6401 DECL_INITIAL (r) = NULL_TREE;
6402 DECL_CONTEXT (r) = ctx;
6404 if (member && DECL_CONV_FN_P (r))
6405 /* Type-conversion operator. Reconstruct the name, in
6406 case it's the name of one of the template's parameters. */
6407 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6409 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6411 DECL_RESULT (r) = NULL_TREE;
6413 TREE_STATIC (r) = 0;
6414 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6415 DECL_EXTERNAL (r) = 1;
6416 /* If this is an instantiation of a function with internal
6417 linkage, we already know what object file linkage will be
6418 assigned to the instantiation. */
6419 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6420 DECL_DEFER_OUTPUT (r) = 0;
6421 TREE_CHAIN (r) = NULL_TREE;
6422 DECL_PENDING_INLINE_INFO (r) = 0;
6423 DECL_PENDING_INLINE_P (r) = 0;
6424 DECL_SAVED_TREE (r) = NULL_TREE;
6426 if (DECL_CLONED_FUNCTION (r))
6428 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6430 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6431 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6434 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6435 this in the special friend case mentioned above where
6436 GEN_TMPL is NULL. */
6439 DECL_TEMPLATE_INFO (r)
6440 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6441 SET_DECL_IMPLICIT_INSTANTIATION (r);
6442 register_specialization (r, gen_tmpl, argvec);
6444 /* We're not supposed to instantiate default arguments
6445 until they are called, for a template. But, for a
6448 template <class T> void f ()
6449 { extern void g(int i = T()); }
6451 we should do the substitution when the template is
6452 instantiated. We handle the member function case in
6453 instantiate_class_template since the default arguments
6454 might refer to other members of the class. */
6456 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6457 && !uses_template_parms (argvec))
6458 tsubst_default_arguments (r);
6461 /* Copy the list of befriending classes. */
6462 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6464 friends = &TREE_CHAIN (*friends))
6466 *friends = copy_node (*friends);
6467 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6472 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6474 maybe_retrofit_in_chrg (r);
6475 if (DECL_CONSTRUCTOR_P (r))
6476 grok_ctor_properties (ctx, r);
6477 /* If this is an instantiation of a member template, clone it.
6478 If it isn't, that'll be handled by
6479 clone_constructors_and_destructors. */
6480 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6481 clone_function_decl (r, /*update_method_vec_p=*/0);
6483 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6484 grok_op_properties (r, DECL_FRIEND_P (r),
6485 (complain & tf_error) != 0);
6487 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6488 SET_DECL_FRIEND_CONTEXT (r,
6489 tsubst (DECL_FRIEND_CONTEXT (t),
6490 args, complain, in_decl));
6499 if (DECL_TEMPLATE_PARM_P (t))
6500 SET_DECL_TEMPLATE_PARM_P (r);
6502 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6503 TREE_TYPE (r) = type;
6504 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6506 if (DECL_INITIAL (r))
6508 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6509 DECL_INITIAL (r) = TREE_TYPE (r);
6511 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6515 DECL_CONTEXT (r) = NULL_TREE;
6517 if (!DECL_TEMPLATE_PARM_P (r))
6518 DECL_ARG_TYPE (r) = type_passed_as (type);
6520 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6521 complain, TREE_CHAIN (t));
6530 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6531 if (type == error_mark_node)
6532 return error_mark_node;
6533 TREE_TYPE (r) = type;
6534 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6536 /* We don't have to set DECL_CONTEXT here; it is set by
6537 finish_member_declaration. */
6538 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6540 TREE_CHAIN (r) = NULL_TREE;
6541 if (VOID_TYPE_P (type))
6542 cp_error_at ("instantiation of %qD as type %qT", r, type);
6549 /* It is not a dependent using decl any more. */
6550 TREE_TYPE (r) = void_type_node;
6552 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6554 = tsubst_copy (DECL_NAME (t), args, complain, in_decl);
6555 TREE_CHAIN (r) = NULL_TREE;
6562 tree argvec = NULL_TREE;
6563 tree gen_tmpl = NULL_TREE;
6565 tree tmpl = NULL_TREE;
6567 tree type = NULL_TREE;
6570 if (TREE_CODE (t) == TYPE_DECL)
6572 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6573 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6574 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6576 /* If this is the canonical decl, we don't have to
6577 mess with instantiations, and often we can't (for
6578 typename, template type parms and such). Note that
6579 TYPE_NAME is not correct for the above test if
6580 we've copied the type for a typedef. */
6581 r = TYPE_NAME (type);
6586 /* Assume this is a non-local variable. */
6589 if (TYPE_P (CP_DECL_CONTEXT (t)))
6590 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6592 in_decl, /*entering_scope=*/1);
6593 else if (DECL_NAMESPACE_SCOPE_P (t))
6594 ctx = DECL_CONTEXT (t);
6597 /* Subsequent calls to pushdecl will fill this in. */
6602 /* Check to see if we already have this specialization. */
6605 tmpl = DECL_TI_TEMPLATE (t);
6606 gen_tmpl = most_general_template (tmpl);
6607 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6608 spec = retrieve_specialization (gen_tmpl, argvec,
6609 /*class_specializations_p=*/false);
6612 spec = retrieve_local_specialization (t);
6621 if (TREE_CODE (r) == VAR_DECL)
6623 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6624 if (type == error_mark_node)
6625 return error_mark_node;
6626 type = complete_type (type);
6627 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6628 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6629 type = check_var_type (DECL_NAME (r), type);
6631 else if (DECL_SELF_REFERENCE_P (t))
6632 SET_DECL_SELF_REFERENCE_P (r);
6633 TREE_TYPE (r) = type;
6634 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6635 DECL_CONTEXT (r) = ctx;
6636 /* Clear out the mangled name and RTL for the instantiation. */
6637 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6638 SET_DECL_RTL (r, NULL_RTX);
6640 /* Don't try to expand the initializer until someone tries to use
6641 this variable; otherwise we run into circular dependencies. */
6642 DECL_INITIAL (r) = NULL_TREE;
6643 SET_DECL_RTL (r, NULL_RTX);
6644 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6646 /* Even if the original location is out of scope, the newly
6647 substituted one is not. */
6648 if (TREE_CODE (r) == VAR_DECL)
6650 DECL_DEAD_FOR_LOCAL (r) = 0;
6651 DECL_INITIALIZED_P (r) = 0;
6656 /* A static data member declaration is always marked
6657 external when it is declared in-class, even if an
6658 initializer is present. We mimic the non-template
6660 DECL_EXTERNAL (r) = 1;
6662 register_specialization (r, gen_tmpl, argvec);
6663 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6664 SET_DECL_IMPLICIT_INSTANTIATION (r);
6667 register_local_specialization (r, t);
6669 TREE_CHAIN (r) = NULL_TREE;
6678 /* Restore the file and line information. */
6679 input_location = saved_loc;
6684 /* Substitute into the ARG_TYPES of a function type. */
6687 tsubst_arg_types (tree arg_types,
6689 tsubst_flags_t complain,
6692 tree remaining_arg_types;
6695 if (!arg_types || arg_types == void_list_node)
6698 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6699 args, complain, in_decl);
6700 if (remaining_arg_types == error_mark_node)
6701 return error_mark_node;
6703 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6704 if (type == error_mark_node)
6705 return error_mark_node;
6706 if (VOID_TYPE_P (type))
6708 if (complain & tf_error)
6710 error ("invalid parameter type %qT", type);
6712 cp_error_at ("in declaration %qD", in_decl);
6714 return error_mark_node;
6717 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6718 top-level qualifiers as required. */
6719 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6721 /* Note that we do not substitute into default arguments here. The
6722 standard mandates that they be instantiated only when needed,
6723 which is done in build_over_call. */
6724 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6725 remaining_arg_types);
6729 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6730 *not* handle the exception-specification for FNTYPE, because the
6731 initial substitution of explicitly provided template parameters
6732 during argument deduction forbids substitution into the
6733 exception-specification:
6737 All references in the function type of the function template to the
6738 corresponding template parameters are replaced by the specified tem-
6739 plate argument values. If a substitution in a template parameter or
6740 in the function type of the function template results in an invalid
6741 type, type deduction fails. [Note: The equivalent substitution in
6742 exception specifications is done only when the function is instanti-
6743 ated, at which point a program is ill-formed if the substitution
6744 results in an invalid type.] */
6747 tsubst_function_type (tree t,
6749 tsubst_flags_t complain,
6756 /* The TYPE_CONTEXT is not used for function/method types. */
6757 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6759 /* Substitute the return type. */
6760 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6761 if (return_type == error_mark_node)
6762 return error_mark_node;
6763 /* The standard does not presently indicate that creation of a
6764 function type with an invalid return type is a deduction failure.
6765 However, that is clearly analogous to creating an array of "void"
6766 or a reference to a reference. This is core issue #486. */
6767 if (TREE_CODE (return_type) == ARRAY_TYPE
6768 || TREE_CODE (return_type) == FUNCTION_TYPE)
6770 if (complain & tf_error)
6772 if (TREE_CODE (return_type) == ARRAY_TYPE)
6773 error ("function returning an array");
6775 error ("function returning a function");
6777 return error_mark_node;
6780 /* Substitute the argument types. */
6781 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6783 if (arg_types == error_mark_node)
6784 return error_mark_node;
6786 /* Construct a new type node and return it. */
6787 if (TREE_CODE (t) == FUNCTION_TYPE)
6788 fntype = build_function_type (return_type, arg_types);
6791 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6792 if (! IS_AGGR_TYPE (r))
6796 Type deduction may fail for any of the following
6799 -- Attempting to create "pointer to member of T" when T
6800 is not a class type. */
6801 if (complain & tf_error)
6802 error ("creating pointer to member function of non-class type %qT",
6804 return error_mark_node;
6807 fntype = build_method_type_directly (r, return_type,
6808 TREE_CHAIN (arg_types));
6810 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6811 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6816 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6817 ARGS into that specification, and return the substituted
6818 specification. If there is no specification, return NULL_TREE. */
6821 tsubst_exception_specification (tree fntype,
6823 tsubst_flags_t complain,
6829 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6830 new_specs = NULL_TREE;
6833 if (! TREE_VALUE (specs))
6839 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6840 if (spec == error_mark_node)
6842 new_specs = add_exception_specifier (new_specs, spec, complain);
6843 specs = TREE_CHAIN (specs);
6849 /* Substitute into the PARMS of a call-declarator. */
6852 tsubst_call_declarator_parms (tree parms,
6854 tsubst_flags_t complain,
6861 if (!parms || parms == void_list_node)
6864 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6865 args, complain, in_decl);
6867 /* Figure out the type of this parameter. */
6868 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6870 /* Figure out the default argument as well. Note that we use
6871 tsubst_expr since the default argument is really an expression. */
6872 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6874 /* Chain this parameter on to the front of those we have already
6875 processed. We don't use hash_tree_cons because that function
6876 doesn't check TREE_PARMLIST. */
6877 new_parms = tree_cons (defarg, type, new_parms);
6882 /* Take the tree structure T and replace template parameters used
6883 therein with the argument vector ARGS. IN_DECL is an associated
6884 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6885 Issue error and warning messages under control of COMPLAIN. Note
6886 that we must be relatively non-tolerant of extensions here, in
6887 order to preserve conformance; if we allow substitutions that
6888 should not be allowed, we may allow argument deductions that should
6889 not succeed, and therefore report ambiguous overload situations
6890 where there are none. In theory, we could allow the substitution,
6891 but indicate that it should have failed, and allow our caller to
6892 make sure that the right thing happens, but we don't try to do this
6895 This function is used for dealing with types, decls and the like;
6896 for expressions, use tsubst_expr or tsubst_copy. */
6899 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6903 if (t == NULL_TREE || t == error_mark_node
6904 || t == integer_type_node
6905 || t == void_type_node
6906 || t == char_type_node
6907 || t == unknown_type_node
6908 || TREE_CODE (t) == NAMESPACE_DECL)
6912 return tsubst_decl (t, args, complain);
6914 if (TREE_CODE (t) == IDENTIFIER_NODE)
6915 type = IDENTIFIER_TYPE_VALUE (t);
6917 type = TREE_TYPE (t);
6919 gcc_assert (type != unknown_type_node);
6922 && TREE_CODE (t) != TYPENAME_TYPE
6923 && TREE_CODE (t) != IDENTIFIER_NODE
6924 && TREE_CODE (t) != FUNCTION_TYPE
6925 && TREE_CODE (t) != METHOD_TYPE)
6926 type = tsubst (type, args, complain, in_decl);
6927 if (type == error_mark_node)
6928 return error_mark_node;
6930 switch (TREE_CODE (t))
6935 return tsubst_aggr_type (t, args, complain, in_decl,
6936 /*entering_scope=*/0);
6939 case IDENTIFIER_NODE:
6951 if (t == integer_type_node)
6954 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6955 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6959 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6961 /* The array dimension behaves like a non-type template arg,
6962 in that we want to fold it as much as possible. */
6963 max = tsubst_template_arg (omax, args, complain, in_decl);
6964 if (!processing_template_decl)
6965 max = decl_constant_value (max);
6967 if (integer_zerop (omax))
6969 /* Still allow an explicit array of size zero. */
6971 pedwarn ("creating array with size zero");
6973 else if (integer_zerop (max)
6974 || (TREE_CODE (max) == INTEGER_CST
6975 && INT_CST_LT (max, integer_zero_node)))
6979 Type deduction may fail for any of the following
6982 Attempting to create an array with a size that is
6983 zero or negative. */
6984 if (complain & tf_error)
6985 error ("creating array with size zero (%qE)", max);
6987 return error_mark_node;
6990 return compute_array_index_type (NULL_TREE, max);
6993 case TEMPLATE_TYPE_PARM:
6994 case TEMPLATE_TEMPLATE_PARM:
6995 case BOUND_TEMPLATE_TEMPLATE_PARM:
6996 case TEMPLATE_PARM_INDEX:
7001 tree arg = NULL_TREE;
7005 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7006 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7007 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7008 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7010 idx = TEMPLATE_TYPE_IDX (t);
7011 level = TEMPLATE_TYPE_LEVEL (t);
7015 idx = TEMPLATE_PARM_IDX (t);
7016 level = TEMPLATE_PARM_LEVEL (t);
7019 levels = TMPL_ARGS_DEPTH (args);
7020 if (level <= levels)
7021 arg = TMPL_ARG (args, level, idx);
7023 if (arg == error_mark_node)
7024 return error_mark_node;
7025 else if (arg != NULL_TREE)
7027 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7029 gcc_assert (TYPE_P (arg));
7030 return cp_build_qualified_type_real
7031 (arg, cp_type_quals (arg) | cp_type_quals (t),
7032 complain | tf_ignore_bad_quals);
7034 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7036 /* We are processing a type constructed from a
7037 template template parameter. */
7038 tree argvec = tsubst (TYPE_TI_ARGS (t),
7039 args, complain, in_decl);
7040 if (argvec == error_mark_node)
7041 return error_mark_node;
7043 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7044 are resolving nested-types in the signature of a
7045 member function templates. Otherwise ARG is a
7046 TEMPLATE_DECL and is the real template to be
7048 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7049 arg = TYPE_NAME (arg);
7051 r = lookup_template_class (arg,
7054 /*entering_scope=*/0,
7056 return cp_build_qualified_type_real
7057 (r, TYPE_QUALS (t), complain);
7060 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7065 /* This can happen during the attempted tsubst'ing in
7066 unify. This means that we don't yet have any information
7067 about the template parameter in question. */
7070 /* If we get here, we must have been looking at a parm for a
7071 more deeply nested template. Make a new version of this
7072 template parameter, but with a lower level. */
7073 switch (TREE_CODE (t))
7075 case TEMPLATE_TYPE_PARM:
7076 case TEMPLATE_TEMPLATE_PARM:
7077 case BOUND_TEMPLATE_TEMPLATE_PARM:
7078 if (cp_type_quals (t))
7080 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7081 r = cp_build_qualified_type_real
7082 (r, cp_type_quals (t),
7083 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7084 ? tf_ignore_bad_quals : 0));
7089 TEMPLATE_TYPE_PARM_INDEX (r)
7090 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7092 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7093 TYPE_MAIN_VARIANT (r) = r;
7094 TYPE_POINTER_TO (r) = NULL_TREE;
7095 TYPE_REFERENCE_TO (r) = NULL_TREE;
7097 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7099 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7101 if (argvec == error_mark_node)
7102 return error_mark_node;
7104 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7105 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7110 case TEMPLATE_PARM_INDEX:
7111 r = reduce_template_parm_level (t, type, levels);
7123 tree purpose, value, chain;
7125 if (t == void_list_node)
7128 purpose = TREE_PURPOSE (t);
7131 purpose = tsubst (purpose, args, complain, in_decl);
7132 if (purpose == error_mark_node)
7133 return error_mark_node;
7135 value = TREE_VALUE (t);
7138 value = tsubst (value, args, complain, in_decl);
7139 if (value == error_mark_node)
7140 return error_mark_node;
7142 chain = TREE_CHAIN (t);
7143 if (chain && chain != void_type_node)
7145 chain = tsubst (chain, args, complain, in_decl);
7146 if (chain == error_mark_node)
7147 return error_mark_node;
7149 if (purpose == TREE_PURPOSE (t)
7150 && value == TREE_VALUE (t)
7151 && chain == TREE_CHAIN (t))
7153 return hash_tree_cons (purpose, value, chain);
7157 /* We should never be tsubsting a binfo. */
7161 /* A vector of template arguments. */
7163 return tsubst_template_args (t, args, complain, in_decl);
7166 case REFERENCE_TYPE:
7168 enum tree_code code;
7170 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7173 code = TREE_CODE (t);
7178 Type deduction may fail for any of the following
7181 -- Attempting to create a pointer to reference type.
7182 -- Attempting to create a reference to a reference type or
7183 a reference to void. */
7184 if (TREE_CODE (type) == REFERENCE_TYPE
7185 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7187 static location_t last_loc;
7189 /* We keep track of the last time we issued this error
7190 message to avoid spewing a ton of messages during a
7191 single bad template instantiation. */
7192 if (complain & tf_error
7193 #ifdef USE_MAPPED_LOCATION
7194 && last_loc != input_location
7196 && (last_loc.line != input_line
7197 || last_loc.file != input_filename)
7201 if (TREE_CODE (type) == VOID_TYPE)
7202 error ("forming reference to void");
7204 error ("forming %s to reference type %qT",
7205 (code == POINTER_TYPE) ? "pointer" : "reference",
7207 last_loc = input_location;
7210 return error_mark_node;
7212 else if (code == POINTER_TYPE)
7214 r = build_pointer_type (type);
7215 if (TREE_CODE (type) == METHOD_TYPE)
7216 r = build_ptrmemfunc_type (r);
7219 r = build_reference_type (type);
7220 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7222 if (r != error_mark_node)
7223 /* Will this ever be needed for TYPE_..._TO values? */
7230 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7231 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7235 Type deduction may fail for any of the following
7238 -- Attempting to create "pointer to member of T" when T
7239 is not a class type. */
7240 if (complain & tf_error)
7241 error ("creating pointer to member of non-class type %qT", r);
7242 return error_mark_node;
7244 if (TREE_CODE (type) == REFERENCE_TYPE)
7246 if (complain & tf_error)
7247 error ("creating pointer to member reference type %qT", type);
7249 return error_mark_node;
7251 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7252 if (TREE_CODE (type) == FUNCTION_TYPE)
7254 /* This is really a method type. The cv qualifiers of the
7255 this pointer should _not_ be determined by the cv
7256 qualifiers of the class type. They should be held
7257 somewhere in the FUNCTION_TYPE, but we don't do that at
7258 the moment. Consider
7259 typedef void (Func) () const;
7261 template <typename T1> void Foo (Func T1::*);
7266 method_type = build_method_type_directly (TYPE_MAIN_VARIANT (r),
7268 TYPE_ARG_TYPES (type));
7269 return build_ptrmemfunc_type (build_pointer_type (method_type));
7272 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7281 fntype = tsubst_function_type (t, args, complain, in_decl);
7282 if (fntype == error_mark_node)
7283 return error_mark_node;
7285 /* Substitute the exception specification. */
7286 specs = tsubst_exception_specification (t, args, complain,
7289 fntype = build_exception_variant (fntype, specs);
7294 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7295 if (domain == error_mark_node)
7296 return error_mark_node;
7298 /* As an optimization, we avoid regenerating the array type if
7299 it will obviously be the same as T. */
7300 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7303 /* These checks should match the ones in grokdeclarator.
7307 The deduction may fail for any of the following reasons:
7309 -- Attempting to create an array with an element type that
7310 is void, a function type, or a reference type, or [DR337]
7311 an abstract class type. */
7312 if (TREE_CODE (type) == VOID_TYPE
7313 || TREE_CODE (type) == FUNCTION_TYPE
7314 || TREE_CODE (type) == REFERENCE_TYPE)
7316 if (complain & tf_error)
7317 error ("creating array of %qT", type);
7318 return error_mark_node;
7320 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7322 if (complain & tf_error)
7323 error ("creating array of %qT, which is an abstract class type",
7325 return error_mark_node;
7328 r = build_cplus_array_type (type, domain);
7335 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7336 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7338 if (e1 == error_mark_node || e2 == error_mark_node)
7339 return error_mark_node;
7341 return fold (build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2));
7347 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7348 if (e == error_mark_node)
7349 return error_mark_node;
7351 return fold (build1 (TREE_CODE (t), TREE_TYPE (t), e));
7356 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7357 in_decl, /*entering_scope=*/1);
7358 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7361 if (ctx == error_mark_node || f == error_mark_node)
7362 return error_mark_node;
7364 if (!IS_AGGR_TYPE (ctx))
7366 if (complain & tf_error)
7367 error ("%qT is not a class, struct, or union type", ctx);
7368 return error_mark_node;
7370 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7372 /* Normally, make_typename_type does not require that the CTX
7373 have complete type in order to allow things like:
7375 template <class T> struct S { typename S<T>::X Y; };
7377 But, such constructs have already been resolved by this
7378 point, so here CTX really should have complete type, unless
7379 it's a partial instantiation. */
7380 ctx = complete_type (ctx);
7381 if (!COMPLETE_TYPE_P (ctx))
7383 if (complain & tf_error)
7384 cxx_incomplete_type_error (NULL_TREE, ctx);
7385 return error_mark_node;
7389 f = make_typename_type (ctx, f, typename_type,
7390 (complain & tf_error) | tf_keep_type_decl);
7391 if (f == error_mark_node)
7393 if (TREE_CODE (f) == TYPE_DECL)
7395 complain |= tf_ignore_bad_quals;
7399 if (TREE_CODE (f) != TYPENAME_TYPE)
7401 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7402 error ("%qT resolves to %qT, which is not an enumeration type",
7404 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7405 error ("%qT resolves to %qT, which is is not a class type",
7409 return cp_build_qualified_type_real
7410 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7413 case UNBOUND_CLASS_TEMPLATE:
7415 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7416 in_decl, /*entering_scope=*/1);
7417 tree name = TYPE_IDENTIFIER (t);
7418 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7420 if (ctx == error_mark_node || name == error_mark_node)
7421 return error_mark_node;
7424 parm_list = tsubst_template_parms (parm_list, args, complain);
7425 return make_unbound_class_template (ctx, name, parm_list, complain);
7435 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7436 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7437 if (e1 == error_mark_node || e2 == error_mark_node)
7438 return error_mark_node;
7440 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7445 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7446 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7447 if (e1 == error_mark_node || e2 == error_mark_node)
7448 return error_mark_node;
7450 return build_nt (TREE_CODE (t), e1, e2);
7457 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7458 complain, in_decl));
7459 return cp_build_qualified_type_real (type,
7461 | cp_type_quals (type),
7466 sorry ("use of %qs in template",
7467 tree_code_name [(int) TREE_CODE (t)]);
7468 return error_mark_node;
7472 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7473 type of the expression on the left-hand side of the "." or "->"
7477 tsubst_baselink (tree baselink, tree object_type,
7478 tree args, tsubst_flags_t complain, tree in_decl)
7481 tree qualifying_scope;
7483 tree template_args = 0;
7484 bool template_id_p = false;
7486 /* A baselink indicates a function from a base class. The
7487 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7488 non-dependent types; otherwise, the lookup could not have
7489 succeeded. However, they may indicate bases of the template
7490 class, rather than the instantiated class.
7492 In addition, lookups that were not ambiguous before may be
7493 ambiguous now. Therefore, we perform the lookup again. */
7494 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7495 fns = BASELINK_FUNCTIONS (baselink);
7496 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7498 template_id_p = true;
7499 template_args = TREE_OPERAND (fns, 1);
7500 fns = TREE_OPERAND (fns, 0);
7502 template_args = tsubst_template_args (template_args, args,
7505 name = DECL_NAME (get_first_fn (fns));
7506 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7508 /* If lookup found a single function, mark it as used at this
7509 point. (If it lookup found multiple functions the one selected
7510 later by overload resolution will be marked as used at that
7512 if (BASELINK_P (baselink))
7513 fns = BASELINK_FUNCTIONS (baselink);
7514 if (!template_id_p && !really_overloaded_fn (fns))
7515 mark_used (OVL_CURRENT (fns));
7517 /* Add back the template arguments, if present. */
7518 if (BASELINK_P (baselink) && template_id_p)
7519 BASELINK_FUNCTIONS (baselink)
7520 = build_nt (TEMPLATE_ID_EXPR,
7521 BASELINK_FUNCTIONS (baselink),
7525 object_type = current_class_type;
7526 return adjust_result_of_qualified_name_lookup (baselink,
7531 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7532 true if the qualified-id will be a postfix-expression in-and-of
7533 itself; false if more of the postfix-expression follows the
7534 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7538 tsubst_qualified_id (tree qualified_id, tree args,
7539 tsubst_flags_t complain, tree in_decl,
7540 bool done, bool address_p)
7548 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7550 /* Figure out what name to look up. */
7551 name = TREE_OPERAND (qualified_id, 1);
7552 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7555 template_args = TREE_OPERAND (name, 1);
7557 template_args = tsubst_template_args (template_args, args,
7559 name = TREE_OPERAND (name, 0);
7563 is_template = false;
7564 template_args = NULL_TREE;
7567 /* Substitute into the qualifying scope. When there are no ARGS, we
7568 are just trying to simplify a non-dependent expression. In that
7569 case the qualifying scope may be dependent, and, in any case,
7570 substituting will not help. */
7571 scope = TREE_OPERAND (qualified_id, 0);
7574 scope = tsubst (scope, args, complain, in_decl);
7575 expr = tsubst_copy (name, args, complain, in_decl);
7580 if (dependent_type_p (scope))
7581 return build_nt (SCOPE_REF, scope, expr);
7583 if (!BASELINK_P (name) && !DECL_P (expr))
7585 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7586 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7587 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7589 if (complain & tf_error)
7591 error ("dependent-name %qE is parsed as a non-type, but "
7592 "instantiation yields a type", qualified_id);
7593 inform ("say %<typename %E%> if a type is meant", qualified_id);
7595 return error_mark_node;
7601 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7603 /* Remember that there was a reference to this entity. */
7607 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7609 if (complain & tf_error)
7610 qualified_name_lookup_error (scope,
7611 TREE_OPERAND (qualified_id, 1),
7613 return error_mark_node;
7617 expr = lookup_template_function (expr, template_args);
7619 if (expr == error_mark_node && complain & tf_error)
7620 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7622 else if (TYPE_P (scope))
7624 expr = (adjust_result_of_qualified_name_lookup
7625 (expr, scope, current_class_type));
7626 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7632 /* Like tsubst, but deals with expressions. This function just replaces
7633 template parms; to finish processing the resultant expression, use
7637 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7639 enum tree_code code;
7642 if (t == NULL_TREE || t == error_mark_node)
7645 code = TREE_CODE (t);
7650 r = retrieve_local_specialization (t);
7651 gcc_assert (r != NULL);
7660 if (DECL_TEMPLATE_PARM_P (t))
7661 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7662 /* There is no need to substitute into namespace-scope
7664 if (DECL_NAMESPACE_SCOPE_P (t))
7666 /* If ARGS is NULL, then T is known to be non-dependent. */
7667 if (args == NULL_TREE)
7668 return decl_constant_value (t);
7670 /* Unfortunately, we cannot just call lookup_name here.
7673 template <int I> int f() {
7675 struct S { void g() { E e = a; } };
7678 When we instantiate f<7>::S::g(), say, lookup_name is not
7679 clever enough to find f<7>::a. */
7681 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7682 /*entering_scope=*/0);
7684 for (v = TYPE_VALUES (enum_type);
7687 if (TREE_PURPOSE (v) == DECL_NAME (t))
7688 return TREE_VALUE (v);
7690 /* We didn't find the name. That should never happen; if
7691 name-lookup found it during preliminary parsing, we
7692 should find it again here during instantiation. */
7698 if (DECL_CONTEXT (t))
7702 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7703 /*entering_scope=*/1);
7704 if (ctx != DECL_CONTEXT (t))
7706 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7709 if (complain & tf_error)
7710 error ("using invalid field %qD", t);
7711 return error_mark_node;
7721 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7722 || local_variable_p (t))
7723 t = tsubst (t, args, complain, in_decl);
7728 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7731 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7732 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7733 args, complain, in_decl);
7734 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7735 return tsubst (t, args, complain, in_decl);
7736 else if (DECL_CLASS_SCOPE_P (t)
7737 && uses_template_parms (DECL_CONTEXT (t)))
7739 /* Template template argument like the following example need
7742 template <template <class> class TT> struct C {};
7743 template <class T> struct D {
7744 template <class U> struct E {};
7749 We are processing the template argument `E' in #1 for
7750 the template instantiation #2. Originally, `E' is a
7751 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7752 have to substitute this with one having context `D<int>'. */
7754 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7755 return lookup_field (context, DECL_NAME(t), 0, false);
7758 /* Ordinary template template argument. */
7762 case REINTERPRET_CAST_EXPR:
7763 case CONST_CAST_EXPR:
7764 case STATIC_CAST_EXPR:
7765 case DYNAMIC_CAST_EXPR:
7768 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7769 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7773 case TRUTH_NOT_EXPR:
7776 case CONVERT_EXPR: /* Unary + */
7785 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7786 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7793 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7794 name = TREE_OPERAND (t, 1);
7795 if (TREE_CODE (name) == BIT_NOT_EXPR)
7797 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7799 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7801 else if (TREE_CODE (name) == SCOPE_REF
7802 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7804 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7806 name = TREE_OPERAND (name, 1);
7807 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7809 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7810 name = build_nt (SCOPE_REF, base, name);
7812 else if (TREE_CODE (name) == BASELINK)
7813 name = tsubst_baselink (name,
7814 non_reference (TREE_TYPE (object)),
7818 name = tsubst_copy (name, args, complain, in_decl);
7819 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7825 case TRUNC_DIV_EXPR:
7827 case FLOOR_DIV_EXPR:
7828 case ROUND_DIV_EXPR:
7829 case EXACT_DIV_EXPR:
7833 case TRUNC_MOD_EXPR:
7834 case FLOOR_MOD_EXPR:
7835 case TRUTH_ANDIF_EXPR:
7836 case TRUTH_ORIF_EXPR:
7837 case TRUTH_AND_EXPR:
7856 case PREDECREMENT_EXPR:
7857 case PREINCREMENT_EXPR:
7858 case POSTDECREMENT_EXPR:
7859 case POSTINCREMENT_EXPR:
7861 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7862 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7865 return build_nt (code,
7866 tsubst_copy (TREE_OPERAND (t, 0), args,
7868 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7874 case PSEUDO_DTOR_EXPR:
7877 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7878 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7879 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7880 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7887 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7888 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7889 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7890 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7897 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7898 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7899 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7900 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7904 case TEMPLATE_ID_EXPR:
7906 /* Substituted template arguments */
7907 tree fn = TREE_OPERAND (t, 0);
7908 tree targs = TREE_OPERAND (t, 1);
7910 fn = tsubst_copy (fn, args, complain, in_decl);
7912 targs = tsubst_template_args (targs, args, complain, in_decl);
7914 return lookup_template_function (fn, targs);
7919 tree purpose, value, chain;
7921 if (t == void_list_node)
7924 purpose = TREE_PURPOSE (t);
7926 purpose = tsubst_copy (purpose, args, complain, in_decl);
7927 value = TREE_VALUE (t);
7929 value = tsubst_copy (value, args, complain, in_decl);
7930 chain = TREE_CHAIN (t);
7931 if (chain && chain != void_type_node)
7932 chain = tsubst_copy (chain, args, complain, in_decl);
7933 if (purpose == TREE_PURPOSE (t)
7934 && value == TREE_VALUE (t)
7935 && chain == TREE_CHAIN (t))
7937 return tree_cons (purpose, value, chain);
7944 case TEMPLATE_TYPE_PARM:
7945 case TEMPLATE_TEMPLATE_PARM:
7946 case BOUND_TEMPLATE_TEMPLATE_PARM:
7947 case TEMPLATE_PARM_INDEX:
7949 case REFERENCE_TYPE:
7955 case UNBOUND_CLASS_TEMPLATE:
7958 return tsubst (t, args, complain, in_decl);
7960 case IDENTIFIER_NODE:
7961 if (IDENTIFIER_TYPENAME_P (t))
7963 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7964 return mangle_conv_op_name_for_type (new_type);
7971 r = build_constructor
7972 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7973 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7974 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7979 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7981 tsubst (TREE_TYPE (t), args, complain, in_decl));
7983 case CLEANUP_POINT_EXPR:
7984 /* We shouldn't have built any of these during initial template
7985 generation. Instead, they should be built during instantiation
7986 in response to the saved STMT_IS_FULL_EXPR_P setting. */
7994 /* Like tsubst_copy for expressions, etc. but also does semantic
7998 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8002 if (t == NULL_TREE || t == error_mark_node)
8005 if (EXPR_HAS_LOCATION (t))
8006 input_location = EXPR_LOCATION (t);
8007 if (STATEMENT_CODE_P (TREE_CODE (t)))
8008 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8010 switch (TREE_CODE (t))
8012 case STATEMENT_LIST:
8014 tree_stmt_iterator i;
8015 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8016 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8020 case CTOR_INITIALIZER:
8021 finish_mem_initializers (tsubst_initializer_list
8022 (TREE_OPERAND (t, 0), args));
8026 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8027 args, complain, in_decl));
8031 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8032 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8033 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8035 finish_expr_stmt (tmp);
8039 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8040 args, complain, in_decl));
8048 decl = DECL_EXPR_DECL (t);
8049 if (TREE_CODE (decl) == LABEL_DECL)
8050 finish_label_decl (DECL_NAME (decl));
8051 else if (TREE_CODE (decl) == USING_DECL)
8053 tree scope = DECL_INITIAL (decl);
8054 tree name = DECL_NAME (decl);
8057 scope = tsubst_expr (scope, args, complain, in_decl);
8058 decl = lookup_qualified_name (scope, name,
8059 /*is_type_p=*/false,
8060 /*complain=*/false);
8061 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8062 qualified_name_lookup_error (scope, name, decl);
8064 do_local_using_decl (decl, scope, name);
8068 init = DECL_INITIAL (decl);
8069 decl = tsubst (decl, args, complain, in_decl);
8070 if (decl != error_mark_node)
8073 DECL_INITIAL (decl) = error_mark_node;
8074 /* By marking the declaration as instantiated, we avoid
8075 trying to instantiate it. Since instantiate_decl can't
8076 handle local variables, and since we've already done
8077 all that needs to be done, that's the right thing to
8079 if (TREE_CODE (decl) == VAR_DECL)
8080 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8081 if (TREE_CODE (decl) == VAR_DECL
8082 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8083 /* Anonymous aggregates are a special case. */
8084 finish_anon_union (decl);
8087 maybe_push_decl (decl);
8088 if (TREE_CODE (decl) == VAR_DECL
8089 && DECL_PRETTY_FUNCTION_P (decl))
8091 /* For __PRETTY_FUNCTION__ we have to adjust the
8093 const char *const name
8094 = cxx_printable_name (current_function_decl, 2);
8095 init = cp_fname_init (name, &TREE_TYPE (decl));
8098 init = tsubst_expr (init, args, complain, in_decl);
8099 cp_finish_decl (decl, init, NULL_TREE, 0);
8104 /* A DECL_EXPR can also be used as an expression, in the condition
8105 clause of an if/for/while construct. */
8110 stmt = begin_for_stmt ();
8111 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8112 finish_for_init_stmt (stmt);
8113 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8114 finish_for_cond (tmp, stmt);
8115 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8116 finish_for_expr (tmp, stmt);
8117 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8118 finish_for_stmt (stmt);
8122 stmt = begin_while_stmt ();
8123 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8124 finish_while_stmt_cond (tmp, stmt);
8125 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8126 finish_while_stmt (stmt);
8130 stmt = begin_do_stmt ();
8131 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8132 finish_do_body (stmt);
8133 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8134 finish_do_stmt (tmp, stmt);
8138 stmt = begin_if_stmt ();
8139 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8140 finish_if_stmt_cond (tmp, stmt);
8141 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8142 finish_then_clause (stmt);
8144 if (ELSE_CLAUSE (t))
8146 begin_else_clause (stmt);
8147 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8148 finish_else_clause (stmt);
8151 finish_if_stmt (stmt);
8155 if (BIND_EXPR_BODY_BLOCK (t))
8156 stmt = begin_function_body ();
8158 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8159 ? BCS_TRY_BLOCK : 0);
8161 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8163 if (BIND_EXPR_BODY_BLOCK (t))
8164 finish_function_body (stmt);
8166 finish_compound_stmt (stmt);
8170 finish_break_stmt ();
8174 finish_continue_stmt ();
8178 stmt = begin_switch_stmt ();
8179 tmp = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
8180 finish_switch_cond (tmp, stmt);
8181 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
8182 finish_switch_stmt (stmt);
8185 case CASE_LABEL_EXPR:
8186 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8187 tsubst_expr (CASE_HIGH (t), args, complain,
8192 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8196 tmp = GOTO_DESTINATION (t);
8197 if (TREE_CODE (tmp) != LABEL_DECL)
8198 /* Computed goto's must be tsubst'd into. On the other hand,
8199 non-computed gotos must not be; the identifier in question
8200 will have no binding. */
8201 tmp = tsubst_expr (tmp, args, complain, in_decl);
8203 tmp = DECL_NAME (tmp);
8204 finish_goto_stmt (tmp);
8208 tmp = finish_asm_stmt
8209 (ASM_VOLATILE_P (t),
8210 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8211 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8212 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8213 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8215 tree asm_expr = tmp;
8216 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8217 asm_expr = TREE_OPERAND (asm_expr, 0);
8218 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8225 stmt = begin_try_block ();
8226 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8227 finish_cleanup_try_block (stmt);
8228 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8234 if (FN_TRY_BLOCK_P (t))
8235 stmt = begin_function_try_block ();
8237 stmt = begin_try_block ();
8239 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8241 if (FN_TRY_BLOCK_P (t))
8242 finish_function_try_block (stmt);
8244 finish_try_block (stmt);
8246 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8247 if (FN_TRY_BLOCK_P (t))
8248 finish_function_handler_sequence (stmt);
8250 finish_handler_sequence (stmt);
8258 stmt = begin_handler ();
8259 if (HANDLER_PARMS (t))
8261 decl = HANDLER_PARMS (t);
8262 decl = tsubst (decl, args, complain, in_decl);
8263 /* Prevent instantiate_decl from trying to instantiate
8264 this variable. We've already done all that needs to be
8266 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8270 finish_handler_parms (decl, stmt);
8271 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8272 finish_handler (stmt);
8277 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8281 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8283 return tsubst_copy_and_build (t, args, complain, in_decl,
8284 /*function_p=*/false);
8290 /* T is a postfix-expression that is not being used in a function
8291 call. Return the substituted version of T. */
8294 tsubst_non_call_postfix_expression (tree t, tree args,
8295 tsubst_flags_t complain,
8298 if (TREE_CODE (t) == SCOPE_REF)
8299 t = tsubst_qualified_id (t, args, complain, in_decl,
8300 /*done=*/false, /*address_p=*/false);
8302 t = tsubst_copy_and_build (t, args, complain, in_decl,
8303 /*function_p=*/false);
8308 /* Like tsubst but deals with expressions and performs semantic
8309 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8312 tsubst_copy_and_build (tree t,
8314 tsubst_flags_t complain,
8318 #define RECUR(NODE) \
8319 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8323 if (t == NULL_TREE || t == error_mark_node)
8326 switch (TREE_CODE (t))
8331 case IDENTIFIER_NODE:
8335 tree qualifying_class;
8336 bool non_integral_constant_expression_p;
8337 const char *error_msg;
8339 if (IDENTIFIER_TYPENAME_P (t))
8341 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8342 t = mangle_conv_op_name_for_type (new_type);
8345 /* Look up the name. */
8346 decl = lookup_name (t, 0);
8348 /* By convention, expressions use ERROR_MARK_NODE to indicate
8349 failure, not NULL_TREE. */
8350 if (decl == NULL_TREE)
8351 decl = error_mark_node;
8353 decl = finish_id_expression (t, decl, NULL_TREE,
8356 /*integral_constant_expression_p=*/false,
8357 /*allow_non_integral_constant_expression_p=*/false,
8358 &non_integral_constant_expression_p,
8362 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8363 decl = unqualified_name_lookup_error (decl);
8367 case TEMPLATE_ID_EXPR:
8370 tree template = RECUR (TREE_OPERAND (t, 0));
8371 tree targs = TREE_OPERAND (t, 1);
8374 targs = tsubst_template_args (targs, args, complain, in_decl);
8376 if (TREE_CODE (template) == COMPONENT_REF)
8378 object = TREE_OPERAND (template, 0);
8379 template = TREE_OPERAND (template, 1);
8383 template = lookup_template_function (template, targs);
8386 return build3 (COMPONENT_REF, TREE_TYPE (template),
8387 object, template, NULL_TREE);
8393 return build_x_indirect_ref (RECUR (TREE_OPERAND (t, 0)), "unary *");
8397 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8398 RECUR (TREE_OPERAND (t, 0)));
8401 return build_functional_cast
8402 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8403 RECUR (TREE_OPERAND (t, 0)));
8405 case REINTERPRET_CAST_EXPR:
8406 return build_reinterpret_cast
8407 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8408 RECUR (TREE_OPERAND (t, 0)));
8410 case CONST_CAST_EXPR:
8411 return build_const_cast
8412 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8413 RECUR (TREE_OPERAND (t, 0)));
8415 case DYNAMIC_CAST_EXPR:
8416 return build_dynamic_cast
8417 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8418 RECUR (TREE_OPERAND (t, 0)));
8420 case STATIC_CAST_EXPR:
8421 return build_static_cast
8422 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8423 RECUR (TREE_OPERAND (t, 0)));
8425 case POSTDECREMENT_EXPR:
8426 case POSTINCREMENT_EXPR:
8427 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8428 args, complain, in_decl);
8429 return build_x_unary_op (TREE_CODE (t), op1);
8431 case PREDECREMENT_EXPR:
8432 case PREINCREMENT_EXPR:
8436 case TRUTH_NOT_EXPR:
8437 case CONVERT_EXPR: /* Unary + */
8440 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8443 op1 = TREE_OPERAND (t, 0);
8444 if (TREE_CODE (op1) == SCOPE_REF)
8445 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8446 /*done=*/true, /*address_p=*/true);
8448 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8450 if (TREE_CODE (op1) == LABEL_DECL)
8451 return finish_label_address_expr (DECL_NAME (op1));
8452 return build_x_unary_op (ADDR_EXPR, op1);
8457 case TRUNC_DIV_EXPR:
8459 case FLOOR_DIV_EXPR:
8460 case ROUND_DIV_EXPR:
8461 case EXACT_DIV_EXPR:
8465 case TRUNC_MOD_EXPR:
8466 case FLOOR_MOD_EXPR:
8467 case TRUTH_ANDIF_EXPR:
8468 case TRUTH_ORIF_EXPR:
8469 case TRUTH_AND_EXPR:
8485 return build_x_binary_op
8487 RECUR (TREE_OPERAND (t, 0)),
8488 RECUR (TREE_OPERAND (t, 1)),
8489 /*overloaded_p=*/NULL);
8492 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8493 /*address_p=*/false);
8496 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8499 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)),
8500 NULL_TREE, NULL_TREE);
8502 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8503 args, complain, in_decl);
8504 /* Remember that there was a reference to this entity. */
8507 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8511 op1 = TREE_OPERAND (t, 0);
8514 /* When there are no ARGS, we are trying to evaluate a
8515 non-dependent expression from the parser. Trying to do
8516 the substitutions may not work. */
8518 op1 = TREE_TYPE (op1);
8527 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8529 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8533 tree r = build_x_modify_expr
8534 (RECUR (TREE_OPERAND (t, 0)),
8535 TREE_CODE (TREE_OPERAND (t, 1)),
8536 RECUR (TREE_OPERAND (t, 2)));
8537 /* TREE_NO_WARNING must be set if either the expression was
8538 parenthesized or it uses an operator such as >>= rather
8539 than plain assignment. In the former case, it was already
8540 set and must be copied. In the latter case,
8541 build_x_modify_expr sets it and it must not be reset
8543 if (TREE_NO_WARNING (t))
8544 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8549 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8550 args, complain, in_decl);
8551 /* Remember that there was a reference to this entity. */
8554 return build_x_arrow (op1);
8558 (RECUR (TREE_OPERAND (t, 0)),
8559 RECUR (TREE_OPERAND (t, 1)),
8560 RECUR (TREE_OPERAND (t, 2)),
8561 RECUR (TREE_OPERAND (t, 3)),
8562 NEW_EXPR_USE_GLOBAL (t));
8565 return delete_sanity
8566 (RECUR (TREE_OPERAND (t, 0)),
8567 RECUR (TREE_OPERAND (t, 1)),
8568 DELETE_EXPR_USE_VEC (t),
8569 DELETE_EXPR_USE_GLOBAL (t));
8572 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8573 RECUR (TREE_OPERAND (t, 1)));
8582 function = TREE_OPERAND (t, 0);
8583 /* When we parsed the expression, we determined whether or
8584 not Koenig lookup should be performed. */
8585 koenig_p = KOENIG_LOOKUP_P (t);
8586 if (TREE_CODE (function) == SCOPE_REF)
8589 function = tsubst_qualified_id (function, args, complain, in_decl,
8591 /*address_p=*/false);
8595 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8596 && (TREE_CODE (TREE_OPERAND (function, 1))
8598 function = tsubst_copy_and_build (function, args, complain,
8601 if (BASELINK_P (function))
8605 call_args = RECUR (TREE_OPERAND (t, 1));
8607 /* We do not perform argument-dependent lookup if normal
8608 lookup finds a non-function, in accordance with the
8609 expected resolution of DR 218. */
8611 && ((is_overloaded_fn (function)
8612 /* If lookup found a member function, the Koenig lookup is
8613 not appropriate, even if an unqualified-name was used
8614 to denote the function. */
8615 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8616 || TREE_CODE (function) == IDENTIFIER_NODE))
8617 function = perform_koenig_lookup (function, call_args);
8619 if (TREE_CODE (function) == IDENTIFIER_NODE)
8621 unqualified_name_lookup_error (function);
8622 return error_mark_node;
8625 /* Remember that there was a reference to this entity. */
8626 if (DECL_P (function))
8627 mark_used (function);
8629 function = convert_from_reference (function);
8631 if (TREE_CODE (function) == OFFSET_REF)
8632 return build_offset_ref_call_from_tree (function, call_args);
8633 if (TREE_CODE (function) == COMPONENT_REF)
8635 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8636 return finish_call_expr (function, call_args,
8637 /*disallow_virtual=*/false,
8638 /*koenig_p=*/false);
8640 return (build_new_method_call
8641 (TREE_OPERAND (function, 0),
8642 TREE_OPERAND (function, 1),
8643 call_args, NULL_TREE,
8644 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8646 return finish_call_expr (function, call_args,
8647 /*disallow_virtual=*/qualified_p,
8652 return build_x_conditional_expr
8653 (RECUR (TREE_OPERAND (t, 0)),
8654 RECUR (TREE_OPERAND (t, 1)),
8655 RECUR (TREE_OPERAND (t, 2)));
8657 case PSEUDO_DTOR_EXPR:
8658 return finish_pseudo_destructor_expr
8659 (RECUR (TREE_OPERAND (t, 0)),
8660 RECUR (TREE_OPERAND (t, 1)),
8661 RECUR (TREE_OPERAND (t, 2)));
8665 tree purpose, value, chain;
8667 if (t == void_list_node)
8670 purpose = TREE_PURPOSE (t);
8672 purpose = RECUR (purpose);
8673 value = TREE_VALUE (t);
8675 value = RECUR (value);
8676 chain = TREE_CHAIN (t);
8677 if (chain && chain != void_type_node)
8678 chain = RECUR (chain);
8679 if (purpose == TREE_PURPOSE (t)
8680 && value == TREE_VALUE (t)
8681 && chain == TREE_CHAIN (t))
8683 return tree_cons (purpose, value, chain);
8691 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8692 args, complain, in_decl);
8693 /* Remember that there was a reference to this entity. */
8694 if (DECL_P (object))
8697 member = TREE_OPERAND (t, 1);
8698 if (BASELINK_P (member))
8699 member = tsubst_baselink (member,
8700 non_reference (TREE_TYPE (object)),
8701 args, complain, in_decl);
8703 member = tsubst_copy (member, args, complain, in_decl);
8705 if (member == error_mark_node)
8706 return error_mark_node;
8707 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8709 if (TREE_CODE (member) == BIT_NOT_EXPR)
8710 return finish_pseudo_destructor_expr (object,
8712 TREE_TYPE (object));
8713 else if (TREE_CODE (member) == SCOPE_REF
8714 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8715 return finish_pseudo_destructor_expr (object,
8717 TREE_TYPE (object));
8719 else if (TREE_CODE (member) == SCOPE_REF
8720 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8725 /* Lookup the template functions now that we know what the
8727 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8728 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8729 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8730 /*is_type_p=*/false,
8731 /*complain=*/false);
8732 if (BASELINK_P (member))
8734 BASELINK_FUNCTIONS (member)
8735 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8737 member = (adjust_result_of_qualified_name_lookup
8738 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8739 TREE_TYPE (object)));
8743 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8745 return error_mark_node;
8748 else if (TREE_CODE (member) == SCOPE_REF
8749 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8750 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8752 if (complain & tf_error)
8754 if (TYPE_P (TREE_OPERAND (member, 0)))
8755 error ("%qT is not a class or namespace",
8756 TREE_OPERAND (member, 0));
8758 error ("%qD is not a class or namespace",
8759 TREE_OPERAND (member, 0));
8761 return error_mark_node;
8763 else if (TREE_CODE (member) == FIELD_DECL)
8764 return finish_non_static_data_member (member, object, NULL_TREE);
8766 return finish_class_member_access_expr (object, member);
8771 (RECUR (TREE_OPERAND (t, 0)));
8777 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8780 /* digest_init will do the wrong thing if we let it. */
8781 if (type && TYPE_PTRMEMFUNC_P (type))
8785 /* We do not want to process the purpose of aggregate
8786 initializers as they are identifier nodes which will be
8787 looked up by digest_init. */
8788 purpose_p = !(type && IS_AGGR_TYPE (type));
8789 for (elts = CONSTRUCTOR_ELTS (t);
8791 elts = TREE_CHAIN (elts))
8793 tree purpose = TREE_PURPOSE (elts);
8794 tree value = TREE_VALUE (elts);
8796 if (purpose && purpose_p)
8797 purpose = RECUR (purpose);
8798 value = RECUR (value);
8799 r = tree_cons (purpose, value, r);
8802 r = build_constructor (NULL_TREE, nreverse (r));
8803 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8806 return digest_init (type, r, 0);
8812 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8813 if (TYPE_P (operand_0))
8814 return get_typeid (operand_0);
8815 return build_typeid (operand_0);
8819 return convert_from_reference (tsubst_copy (t, args, complain, in_decl));
8823 t = tsubst_copy (t, args, complain, in_decl);
8824 return convert_from_reference (t);
8827 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8828 tsubst_copy (TREE_TYPE (t), args, complain,
8832 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8836 tree old_stmt_expr = cur_stmt_expr;
8837 tree stmt_expr = begin_stmt_expr ();
8839 cur_stmt_expr = stmt_expr;
8840 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8841 stmt_expr = finish_stmt_expr (stmt_expr, false);
8842 cur_stmt_expr = old_stmt_expr;
8848 t = tsubst_copy (t, args, complain, in_decl);
8849 /* As in finish_id_expression, we resolve enumeration constants
8850 to their underlying values. */
8851 if (TREE_CODE (t) == CONST_DECL)
8852 return DECL_INITIAL (t);
8856 return tsubst_copy (t, args, complain, in_decl);
8862 /* Verify that the instantiated ARGS are valid. For type arguments,
8863 make sure that the type's linkage is ok. For non-type arguments,
8864 make sure they are constants if they are integral or enumerations.
8865 Emit an error under control of COMPLAIN, and return TRUE on error. */
8868 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8870 int ix, len = DECL_NTPARMS (tmpl);
8871 bool result = false;
8873 for (ix = 0; ix != len; ix++)
8875 tree t = TREE_VEC_ELT (args, ix);
8879 /* [basic.link]: A name with no linkage (notably, the name
8880 of a class or enumeration declared in a local scope)
8881 shall not be used to declare an entity with linkage.
8882 This implies that names with no linkage cannot be used as
8883 template arguments. */
8884 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8888 if (!(complain & tf_error))
8890 else if (TYPE_ANONYMOUS_P (nt))
8891 error ("%qT uses anonymous type", t);
8893 error ("%qT uses local type %qT", t, nt);
8896 /* In order to avoid all sorts of complications, we do not
8897 allow variably-modified types as template arguments. */
8898 else if (variably_modified_type_p (t, NULL_TREE))
8900 if (complain & tf_error)
8901 error ("%qT is a variably modified type", t);
8905 /* A non-type argument of integral or enumerated type must be a
8907 else if (TREE_TYPE (t)
8908 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8909 && !TREE_CONSTANT (t))
8911 if (complain & tf_error)
8912 error ("integral expression %qE is not constant", t);
8916 if (result && complain & tf_error)
8917 error (" trying to instantiate %qD", tmpl);
8921 /* Instantiate the indicated variable or function template TMPL with
8922 the template arguments in TARG_PTR. */
8925 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8931 if (tmpl == error_mark_node)
8932 return error_mark_node;
8934 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
8936 /* If this function is a clone, handle it specially. */
8937 if (DECL_CLONED_FUNCTION_P (tmpl))
8942 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8944 if (spec == error_mark_node)
8945 return error_mark_node;
8947 /* Look for the clone. */
8948 FOR_EACH_CLONE (clone, spec)
8949 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8951 /* We should always have found the clone by now. */
8956 /* Check to see if we already have this specialization. */
8957 spec = retrieve_specialization (tmpl, targ_ptr,
8958 /*class_specializations_p=*/false);
8959 if (spec != NULL_TREE)
8962 gen_tmpl = most_general_template (tmpl);
8963 if (tmpl != gen_tmpl)
8965 /* The TMPL is a partial instantiation. To get a full set of
8966 arguments we must add the arguments used to perform the
8967 partial instantiation. */
8968 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
8971 /* Check to see if we already have this specialization. */
8972 spec = retrieve_specialization (gen_tmpl, targ_ptr,
8973 /*class_specializations_p=*/false);
8974 if (spec != NULL_TREE)
8978 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
8980 return error_mark_node;
8982 /* We are building a FUNCTION_DECL, during which the access of its
8983 parameters and return types have to be checked. However this
8984 FUNCTION_DECL which is the desired context for access checking
8985 is not built yet. We solve this chicken-and-egg problem by
8986 deferring all checks until we have the FUNCTION_DECL. */
8987 push_deferring_access_checks (dk_deferred);
8989 /* Substitute template parameters. */
8990 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
8991 targ_ptr, complain, gen_tmpl);
8993 /* Now we know the specialization, compute access previously
8995 push_access_scope (fndecl);
8996 perform_deferred_access_checks ();
8997 pop_access_scope (fndecl);
8998 pop_deferring_access_checks ();
9000 /* The DECL_TI_TEMPLATE should always be the immediate parent
9001 template, not the most general template. */
9002 DECL_TI_TEMPLATE (fndecl) = tmpl;
9004 /* If we've just instantiated the main entry point for a function,
9005 instantiate all the alternate entry points as well. We do this
9006 by cloning the instantiation of the main entry point, not by
9007 instantiating the template clones. */
9008 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9009 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9014 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9015 arguments that are being used when calling it. TARGS is a vector
9016 into which the deduced template arguments are placed.
9018 Return zero for success, 2 for an incomplete match that doesn't resolve
9019 all the types, and 1 for complete failure. An error message will be
9020 printed only for an incomplete match.
9022 If FN is a conversion operator, or we are trying to produce a specific
9023 specialization, RETURN_TYPE is the return type desired.
9025 The EXPLICIT_TARGS are explicit template arguments provided via a
9028 The parameter STRICT is one of:
9031 We are deducing arguments for a function call, as in
9035 We are deducing arguments for a conversion function, as in
9039 We are deducing arguments when doing an explicit instantiation
9040 as in [temp.explicit], when determining an explicit specialization
9041 as in [temp.expl.spec], or when taking the address of a function
9042 template, as in [temp.deduct.funcaddr].
9045 We are deducing arguments when calculating the partial
9046 ordering between specializations of function or class
9047 templates, as in [temp.func.order] and [temp.class.order].
9049 LEN is the number of parms to consider before returning success, or -1
9050 for all. This is used in partial ordering to avoid comparing parms for
9051 which no actual argument was passed, since they are not considered in
9052 overload resolution (and are explicitly excluded from consideration in
9053 partial ordering in [temp.func.order]/6). */
9056 fn_type_unification (tree fn,
9057 tree explicit_targs,
9061 unification_kind_t strict,
9068 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9070 fntype = TREE_TYPE (fn);
9075 The specified template arguments must match the template
9076 parameters in kind (i.e., type, nontype, template), and there
9077 must not be more arguments than there are parameters;
9078 otherwise type deduction fails.
9080 Nontype arguments must match the types of the corresponding
9081 nontype template parameters, or must be convertible to the
9082 types of the corresponding nontype parameters as specified in
9083 _temp.arg.nontype_, otherwise type deduction fails.
9085 All references in the function type of the function template
9086 to the corresponding template parameters are replaced by the
9087 specified template argument values. If a substitution in a
9088 template parameter or in the function type of the function
9089 template results in an invalid type, type deduction fails. */
9091 tree converted_args;
9095 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9096 explicit_targs, NULL_TREE, tf_none,
9097 /*require_all_arguments=*/0));
9098 if (converted_args == error_mark_node)
9101 /* Substitute the explicit args into the function type. This is
9102 necessary so that, for instance, explicitly declared function
9103 arguments can match null pointed constants. If we were given
9104 an incomplete set of explicit args, we must not do semantic
9105 processing during substitution as we could create partial
9107 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9108 processing_template_decl += incomplete;
9109 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9110 processing_template_decl -= incomplete;
9112 if (fntype == error_mark_node)
9115 /* Place the explicitly specified arguments in TARGS. */
9116 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9117 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9120 parms = TYPE_ARG_TYPES (fntype);
9121 /* Never do unification on the 'this' parameter. */
9122 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9123 parms = TREE_CHAIN (parms);
9127 /* We've been given a return type to match, prepend it. */
9128 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9129 args = tree_cons (NULL_TREE, return_type, args);
9134 /* We allow incomplete unification without an error message here
9135 because the standard doesn't seem to explicitly prohibit it. Our
9136 callers must be ready to deal with unification failures in any
9138 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9139 targs, parms, args, /*subr=*/0,
9140 strict, /*allow_incomplete*/1, len);
9143 /* All is well so far. Now, check:
9147 When all template arguments have been deduced, all uses of
9148 template parameters in nondeduced contexts are replaced with
9149 the corresponding deduced argument values. If the
9150 substitution results in an invalid type, as described above,
9151 type deduction fails. */
9152 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9159 /* Adjust types before performing type deduction, as described in
9160 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9161 sections are symmetric. PARM is the type of a function parameter
9162 or the return type of the conversion function. ARG is the type of
9163 the argument passed to the call, or the type of the value
9164 initialized with the result of the conversion function. */
9167 maybe_adjust_types_for_deduction (unification_kind_t strict,
9180 /* Swap PARM and ARG throughout the remainder of this
9181 function; the handling is precisely symmetric since PARM
9182 will initialize ARG rather than vice versa. */
9190 /* There is nothing to do in this case. */
9194 /* DR 214. [temp.func.order] is underspecified, and leads to no
9195 ordering between things like `T *' and `T const &' for `U *'.
9196 The former has T=U and the latter T=U*. The former looks more
9197 specialized and John Spicer considers it well-formed (the EDG
9198 compiler accepts it).
9200 John also confirms that deduction should proceed as in a function
9201 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
9202 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
9203 to an actual call can have such a type.
9205 If both ARG and PARM are REFERENCE_TYPE, we change neither.
9206 If only ARG is a REFERENCE_TYPE, we look through that and then
9207 proceed as with DEDUCE_CALL (which could further convert it). */
9208 if (TREE_CODE (*arg) == REFERENCE_TYPE)
9210 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9212 *arg = TREE_TYPE (*arg);
9219 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9221 /* [temp.deduct.call]
9223 If P is not a reference type:
9225 --If A is an array type, the pointer type produced by the
9226 array-to-pointer standard conversion (_conv.array_) is
9227 used in place of A for type deduction; otherwise,
9229 --If A is a function type, the pointer type produced by
9230 the function-to-pointer standard conversion
9231 (_conv.func_) is used in place of A for type deduction;
9234 --If A is a cv-qualified type, the top level
9235 cv-qualifiers of A's type are ignored for type
9237 if (TREE_CODE (*arg) == ARRAY_TYPE)
9238 *arg = build_pointer_type (TREE_TYPE (*arg));
9239 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9240 *arg = build_pointer_type (*arg);
9242 *arg = TYPE_MAIN_VARIANT (*arg);
9245 /* [temp.deduct.call]
9247 If P is a cv-qualified type, the top level cv-qualifiers
9248 of P's type are ignored for type deduction. If P is a
9249 reference type, the type referred to by P is used for
9251 *parm = TYPE_MAIN_VARIANT (*parm);
9252 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9254 *parm = TREE_TYPE (*parm);
9255 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9258 /* DR 322. For conversion deduction, remove a reference type on parm
9259 too (which has been swapped into ARG). */
9260 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9261 *arg = TREE_TYPE (*arg);
9266 /* Most parms like fn_type_unification.
9268 If SUBR is 1, we're being called recursively (to unify the
9269 arguments of a function or method parameter of a function
9273 type_unification_real (tree tparms,
9278 unification_kind_t strict,
9279 int allow_incomplete,
9284 int ntparms = TREE_VEC_LENGTH (tparms);
9286 int saw_undeduced = 0;
9290 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9291 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9292 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9293 gcc_assert (ntparms > 0);
9298 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9299 | UNIFY_ALLOW_DERIVED);
9303 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9307 sub_strict = UNIFY_ALLOW_NONE;
9311 sub_strict = UNIFY_ALLOW_NONE;
9327 && parms != void_list_node
9329 && args != void_list_node)
9331 parm = TREE_VALUE (parms);
9332 parms = TREE_CHAIN (parms);
9333 arg = TREE_VALUE (args);
9334 args = TREE_CHAIN (args);
9336 if (arg == error_mark_node)
9338 if (arg == unknown_type_node)
9339 /* We can't deduce anything from this, but we might get all the
9340 template args from other function args. */
9343 /* Conversions will be performed on a function argument that
9344 corresponds with a function parameter that contains only
9345 non-deducible template parameters and explicitly specified
9346 template parameters. */
9347 if (!uses_template_parms (parm))
9352 type = TREE_TYPE (arg);
9356 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
9358 if (same_type_p (parm, type))
9362 /* It might work; we shouldn't check now, because we might
9363 get into infinite recursion. Overload resolution will
9372 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9373 if (type_unknown_p (arg))
9375 /* [temp.deduct.type] A template-argument can be deduced from
9376 a pointer to function or pointer to member function
9377 argument if the set of overloaded functions does not
9378 contain function templates and at most one of a set of
9379 overloaded functions provides a unique match. */
9381 if (resolve_overloaded_unification
9382 (tparms, targs, parm, arg, strict, sub_strict)
9387 arg = TREE_TYPE (arg);
9388 if (arg == error_mark_node)
9393 int arg_strict = sub_strict;
9396 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9398 if (unify (tparms, targs, parm, arg, arg_strict))
9402 /* Are we done with the interesting parms? */
9406 /* Fail if we've reached the end of the parm list, and more args
9407 are present, and the parm list isn't variadic. */
9408 if (args && args != void_list_node && parms == void_list_node)
9410 /* Fail if parms are left and they don't have default values. */
9412 && parms != void_list_node
9413 && TREE_PURPOSE (parms) == NULL_TREE)
9418 for (i = 0; i < ntparms; i++)
9419 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
9421 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9423 /* If this is an undeduced nontype parameter that depends on
9424 a type parameter, try another pass; its type may have been
9425 deduced from a later argument than the one from which
9426 this parameter can be deduced. */
9427 if (TREE_CODE (tparm) == PARM_DECL
9428 && uses_template_parms (TREE_TYPE (tparm))
9429 && !saw_undeduced++)
9432 if (!allow_incomplete)
9433 error ("incomplete type unification");
9439 /* Subroutine of type_unification_real. Args are like the variables at the
9440 call site. ARG is an overloaded function (or template-id); we try
9441 deducing template args from each of the overloads, and if only one
9442 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9445 resolve_overloaded_unification (tree tparms,
9449 unification_kind_t strict,
9452 tree tempargs = copy_node (targs);
9456 if (TREE_CODE (arg) == ADDR_EXPR)
9458 arg = TREE_OPERAND (arg, 0);
9464 if (TREE_CODE (arg) == COMPONENT_REF)
9465 /* Handle `&x' where `x' is some static or non-static member
9467 arg = TREE_OPERAND (arg, 1);
9469 if (TREE_CODE (arg) == OFFSET_REF)
9470 arg = TREE_OPERAND (arg, 1);
9472 /* Strip baselink information. */
9473 if (BASELINK_P (arg))
9474 arg = BASELINK_FUNCTIONS (arg);
9476 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9478 /* If we got some explicit template args, we need to plug them into
9479 the affected templates before we try to unify, in case the
9480 explicit args will completely resolve the templates in question. */
9482 tree expl_subargs = TREE_OPERAND (arg, 1);
9483 arg = TREE_OPERAND (arg, 0);
9485 for (; arg; arg = OVL_NEXT (arg))
9487 tree fn = OVL_CURRENT (arg);
9490 if (TREE_CODE (fn) != TEMPLATE_DECL)
9493 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
9497 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9498 good += try_one_overload (tparms, targs, tempargs, parm,
9499 elem, strict, sub_strict, addr_p);
9505 gcc_assert (TREE_CODE (arg) == OVERLOAD
9506 || TREE_CODE (arg) == FUNCTION_DECL);
9508 for (; arg; arg = OVL_NEXT (arg))
9509 good += try_one_overload (tparms, targs, tempargs, parm,
9510 TREE_TYPE (OVL_CURRENT (arg)),
9511 strict, sub_strict, addr_p);
9514 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9515 to function or pointer to member function argument if the set of
9516 overloaded functions does not contain function templates and at most
9517 one of a set of overloaded functions provides a unique match.
9519 So if we found multiple possibilities, we return success but don't
9524 int i = TREE_VEC_LENGTH (targs);
9526 if (TREE_VEC_ELT (tempargs, i))
9527 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9535 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9536 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9537 different overloads deduce different arguments for a given parm.
9538 ADDR_P is true if the expression for which deduction is being
9539 performed was of the form "& fn" rather than simply "fn".
9541 Returns 1 on success. */
9544 try_one_overload (tree tparms,
9549 unification_kind_t strict,
9557 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9558 to function or pointer to member function argument if the set of
9559 overloaded functions does not contain function templates and at most
9560 one of a set of overloaded functions provides a unique match.
9562 So if this is a template, just return success. */
9564 if (uses_template_parms (arg))
9567 if (TREE_CODE (arg) == METHOD_TYPE)
9568 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9570 arg = build_pointer_type (arg);
9572 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9574 /* We don't copy orig_targs for this because if we have already deduced
9575 some template args from previous args, unify would complain when we
9576 try to deduce a template parameter for the same argument, even though
9577 there isn't really a conflict. */
9578 nargs = TREE_VEC_LENGTH (targs);
9579 tempargs = make_tree_vec (nargs);
9581 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9584 /* First make sure we didn't deduce anything that conflicts with
9585 explicitly specified args. */
9586 for (i = nargs; i--; )
9588 tree elt = TREE_VEC_ELT (tempargs, i);
9589 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9591 if (elt == NULL_TREE)
9593 else if (uses_template_parms (elt))
9595 /* Since we're unifying against ourselves, we will fill in template
9596 args used in the function parm list with our own template parms.
9598 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9601 else if (oldelt && ! template_args_equal (oldelt, elt))
9605 for (i = nargs; i--; )
9607 tree elt = TREE_VEC_ELT (tempargs, i);
9610 TREE_VEC_ELT (targs, i) = elt;
9616 /* Verify that nondeduce template argument agrees with the type
9617 obtained from argument deduction. Return nonzero if the
9622 struct A { typedef int X; };
9623 template <class T, class U> struct C {};
9624 template <class T> struct C<T, typename T::X> {};
9626 Then with the instantiation `C<A, int>', we can deduce that
9627 `T' is `A' but unify () does not check whether `typename T::X'
9628 is `int'. This function ensure that they agree.
9630 TARGS, PARMS are the same as the arguments of unify.
9631 ARGS contains template arguments from all levels. */
9634 verify_class_unification (tree targs, tree parms, tree args)
9636 parms = tsubst (parms, add_outermost_template_args (args, targs),
9637 tf_none, NULL_TREE);
9638 if (parms == error_mark_node)
9641 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9644 /* PARM is a template class (perhaps with unbound template
9645 parameters). ARG is a fully instantiated type. If ARG can be
9646 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9647 TARGS are as for unify. */
9650 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9654 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9655 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9656 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9659 /* We need to make a new template argument vector for the call to
9660 unify. If we used TARGS, we'd clutter it up with the result of
9661 the attempted unification, even if this class didn't work out.
9662 We also don't want to commit ourselves to all the unifications
9663 we've already done, since unification is supposed to be done on
9664 an argument-by-argument basis. In other words, consider the
9665 following pathological case:
9667 template <int I, int J, int K>
9670 template <int I, int J>
9671 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9673 template <int I, int J, int K>
9674 void f(S<I, J, K>, S<I, I, I>);
9683 Now, by the time we consider the unification involving `s2', we
9684 already know that we must have `f<0, 0, 0>'. But, even though
9685 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9686 because there are two ways to unify base classes of S<0, 1, 2>
9687 with S<I, I, I>. If we kept the already deduced knowledge, we
9688 would reject the possibility I=1. */
9689 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9691 /* If unification failed, we're done. */
9692 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9693 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9699 /* Given a template type PARM and a class type ARG, find the unique
9700 base type in ARG that is an instance of PARM. We do not examine
9701 ARG itself; only its base-classes. If there is not exactly one
9702 appropriate base class, return NULL_TREE. PARM may be the type of
9703 a partial specialization, as well as a plain template type. Used
9707 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9709 tree rval = NULL_TREE;
9712 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9714 binfo = TYPE_BINFO (complete_type (arg));
9716 /* The type could not be completed. */
9719 /* Walk in inheritance graph order. The search order is not
9720 important, and this avoids multiple walks of virtual bases. */
9721 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9723 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9727 /* If there is more than one satisfactory baseclass, then:
9731 If they yield more than one possible deduced A, the type
9735 if (rval && !same_type_p (r, rval))
9745 /* Returns the level of DECL, which declares a template parameter. */
9748 template_decl_level (tree decl)
9750 switch (TREE_CODE (decl))
9754 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9757 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9765 /* Decide whether ARG can be unified with PARM, considering only the
9766 cv-qualifiers of each type, given STRICT as documented for unify.
9767 Returns nonzero iff the unification is OK on that basis. */
9770 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9772 int arg_quals = cp_type_quals (arg);
9773 int parm_quals = cp_type_quals (parm);
9775 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9776 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9778 /* Although a CVR qualifier is ignored when being applied to a
9779 substituted template parameter ([8.3.2]/1 for example), that
9780 does not apply during deduction [14.8.2.4]/1, (even though
9781 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9782 this). Except when we're allowing additional CV qualifiers
9783 at the outer level [14.8.2.1]/3,1st bullet. */
9784 if ((TREE_CODE (arg) == REFERENCE_TYPE
9785 || TREE_CODE (arg) == FUNCTION_TYPE
9786 || TREE_CODE (arg) == METHOD_TYPE)
9787 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9790 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9791 && (parm_quals & TYPE_QUAL_RESTRICT))
9795 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9796 && (arg_quals & parm_quals) != parm_quals)
9799 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9800 && (parm_quals & arg_quals) != arg_quals)
9806 /* Takes parameters as for type_unification. Returns 0 if the
9807 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9808 bitwise or of the following flags:
9811 Require an exact match between PARM and ARG.
9812 UNIFY_ALLOW_MORE_CV_QUAL:
9813 Allow the deduced ARG to be more cv-qualified (by qualification
9814 conversion) than ARG.
9815 UNIFY_ALLOW_LESS_CV_QUAL:
9816 Allow the deduced ARG to be less cv-qualified than ARG.
9817 UNIFY_ALLOW_DERIVED:
9818 Allow the deduced ARG to be a template base class of ARG,
9819 or a pointer to a template base class of the type pointed to by
9821 UNIFY_ALLOW_INTEGER:
9822 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9823 case for more information.
9824 UNIFY_ALLOW_OUTER_LEVEL:
9825 This is the outermost level of a deduction. Used to determine validity
9826 of qualification conversions. A valid qualification conversion must
9827 have const qualified pointers leading up to the inner type which
9828 requires additional CV quals, except at the outer level, where const
9829 is not required [conv.qual]. It would be normal to set this flag in
9830 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9831 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9832 This is the outermost level of a deduction, and PARM can be more CV
9833 qualified at this point.
9834 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9835 This is the outermost level of a deduction, and PARM can be less CV
9836 qualified at this point. */
9839 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9844 int strict_in = strict;
9846 /* I don't think this will do the right thing with respect to types.
9847 But the only case I've seen it in so far has been array bounds, where
9848 signedness is the only information lost, and I think that will be
9850 while (TREE_CODE (parm) == NOP_EXPR)
9851 parm = TREE_OPERAND (parm, 0);
9853 if (arg == error_mark_node)
9855 if (arg == unknown_type_node)
9856 /* We can't deduce anything from this, but we might get all the
9857 template args from other function args. */
9860 /* If PARM uses template parameters, then we can't bail out here,
9861 even if ARG == PARM, since we won't record unifications for the
9862 template parameters. We might need them if we're trying to
9863 figure out which of two things is more specialized. */
9864 if (arg == parm && !uses_template_parms (parm))
9867 /* Immediately reject some pairs that won't unify because of
9868 cv-qualification mismatches. */
9869 if (TREE_CODE (arg) == TREE_CODE (parm)
9871 /* It is the elements of the array which hold the cv quals of an array
9872 type, and the elements might be template type parms. We'll check
9874 && TREE_CODE (arg) != ARRAY_TYPE
9875 /* We check the cv-qualifiers when unifying with template type
9876 parameters below. We want to allow ARG `const T' to unify with
9877 PARM `T' for example, when computing which of two templates
9878 is more specialized, for example. */
9879 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9880 && !check_cv_quals_for_unify (strict_in, arg, parm))
9883 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9884 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9885 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9886 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9887 strict &= ~UNIFY_ALLOW_DERIVED;
9888 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9889 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9891 switch (TREE_CODE (parm))
9895 case UNBOUND_CLASS_TEMPLATE:
9896 /* In a type which contains a nested-name-specifier, template
9897 argument values cannot be deduced for template parameters used
9898 within the nested-name-specifier. */
9901 case TEMPLATE_TYPE_PARM:
9902 case TEMPLATE_TEMPLATE_PARM:
9903 case BOUND_TEMPLATE_TEMPLATE_PARM:
9904 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9906 if (TEMPLATE_TYPE_LEVEL (parm)
9907 != template_decl_level (tparm))
9908 /* The PARM is not one we're trying to unify. Just check
9909 to see if it matches ARG. */
9910 return (TREE_CODE (arg) == TREE_CODE (parm)
9911 && same_type_p (parm, arg)) ? 0 : 1;
9912 idx = TEMPLATE_TYPE_IDX (parm);
9913 targ = TREE_VEC_ELT (targs, idx);
9914 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9916 /* Check for mixed types and values. */
9917 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9918 && TREE_CODE (tparm) != TYPE_DECL)
9919 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9920 && TREE_CODE (tparm) != TEMPLATE_DECL))
9923 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9925 /* ARG must be constructed from a template class or a template
9926 template parameter. */
9927 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9928 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9932 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9933 tree parmvec = TYPE_TI_ARGS (parm);
9934 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9936 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9939 /* The parameter and argument roles have to be switched here
9940 in order to handle default arguments properly. For example,
9941 template<template <class> class TT> void f(TT<int>)
9942 should be able to accept vector<int> which comes from
9943 template <class T, class Allocator = allocator>
9946 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9950 /* Deduce arguments T, i from TT<T> or TT<i>.
9951 We check each element of PARMVEC and ARGVEC individually
9952 rather than the whole TREE_VEC since they can have
9953 different number of elements. */
9955 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9957 if (unify (tparms, targs,
9958 TREE_VEC_ELT (parmvec, i),
9959 TREE_VEC_ELT (argvec, i),
9964 arg = TYPE_TI_TEMPLATE (arg);
9966 /* Fall through to deduce template name. */
9969 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9970 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9972 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9974 /* Simple cases: Value already set, does match or doesn't. */
9975 if (targ != NULL_TREE && template_args_equal (targ, arg))
9982 /* If PARM is `const T' and ARG is only `int', we don't have
9983 a match unless we are allowing additional qualification.
9984 If ARG is `const int' and PARM is just `T' that's OK;
9985 that binds `const int' to `T'. */
9986 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
9990 /* Consider the case where ARG is `const volatile int' and
9991 PARM is `const T'. Then, T should be `volatile int'. */
9992 arg = cp_build_qualified_type_real
9993 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
9994 if (arg == error_mark_node)
9997 /* Simple cases: Value already set, does match or doesn't. */
9998 if (targ != NULL_TREE && same_type_p (targ, arg))
10003 /* Make sure that ARG is not a variable-sized array. (Note
10004 that were talking about variable-sized arrays (like
10005 `int[n]'), rather than arrays of unknown size (like
10006 `int[]').) We'll get very confused by such a type since
10007 the bound of the array will not be computable in an
10008 instantiation. Besides, such types are not allowed in
10009 ISO C++, so we can do as we please here. */
10010 if (variably_modified_type_p (arg, NULL_TREE))
10014 TREE_VEC_ELT (targs, idx) = arg;
10017 case TEMPLATE_PARM_INDEX:
10018 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10020 if (TEMPLATE_PARM_LEVEL (parm)
10021 != template_decl_level (tparm))
10022 /* The PARM is not one we're trying to unify. Just check
10023 to see if it matches ARG. */
10024 return !(TREE_CODE (arg) == TREE_CODE (parm)
10025 && cp_tree_equal (parm, arg));
10027 idx = TEMPLATE_PARM_IDX (parm);
10028 targ = TREE_VEC_ELT (targs, idx);
10031 return !cp_tree_equal (targ, arg);
10033 /* [temp.deduct.type] If, in the declaration of a function template
10034 with a non-type template-parameter, the non-type
10035 template-parameter is used in an expression in the function
10036 parameter-list and, if the corresponding template-argument is
10037 deduced, the template-argument type shall match the type of the
10038 template-parameter exactly, except that a template-argument
10039 deduced from an array bound may be of any integral type.
10040 The non-type parameter might use already deduced type parameters. */
10041 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10042 if (!TREE_TYPE (arg))
10043 /* Template-parameter dependent expression. Just accept it for now.
10044 It will later be processed in convert_template_argument. */
10046 else if (same_type_p (TREE_TYPE (arg), tparm))
10048 else if ((strict & UNIFY_ALLOW_INTEGER)
10049 && (TREE_CODE (tparm) == INTEGER_TYPE
10050 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10051 /* Convert the ARG to the type of PARM; the deduced non-type
10052 template argument must exactly match the types of the
10053 corresponding parameter. */
10054 arg = fold (build_nop (TREE_TYPE (parm), arg));
10055 else if (uses_template_parms (tparm))
10056 /* We haven't deduced the type of this parameter yet. Try again
10062 TREE_VEC_ELT (targs, idx) = arg;
10067 /* A pointer-to-member constant can be unified only with
10068 another constant. */
10069 if (TREE_CODE (arg) != PTRMEM_CST)
10072 /* Just unify the class member. It would be useless (and possibly
10073 wrong, depending on the strict flags) to unify also
10074 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10075 arg refer to the same variable, even if through different
10076 classes. For instance:
10078 struct A { int x; };
10081 Unification of &A::x and &B::x must succeed. */
10082 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10083 PTRMEM_CST_MEMBER (arg), strict);
10088 if (TREE_CODE (arg) != POINTER_TYPE)
10091 /* [temp.deduct.call]
10093 A can be another pointer or pointer to member type that can
10094 be converted to the deduced A via a qualification
10095 conversion (_conv.qual_).
10097 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10098 This will allow for additional cv-qualification of the
10099 pointed-to types if appropriate. */
10101 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10102 /* The derived-to-base conversion only persists through one
10103 level of pointers. */
10104 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10106 return unify (tparms, targs, TREE_TYPE (parm),
10107 TREE_TYPE (arg), strict);
10110 case REFERENCE_TYPE:
10111 if (TREE_CODE (arg) != REFERENCE_TYPE)
10113 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10114 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10117 if (TREE_CODE (arg) != ARRAY_TYPE)
10119 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10120 != (TYPE_DOMAIN (arg) == NULL_TREE))
10122 if (TYPE_DOMAIN (parm) != NULL_TREE)
10127 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10128 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10130 /* Our representation of array types uses "N - 1" as the
10131 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10132 not an integer constant. */
10133 if (TREE_CODE (parm_max) == MINUS_EXPR)
10135 arg_max = fold (build2 (PLUS_EXPR,
10138 TREE_OPERAND (parm_max, 1)));
10139 parm_max = TREE_OPERAND (parm_max, 0);
10142 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10145 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10146 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10153 case ENUMERAL_TYPE:
10155 if (TREE_CODE (arg) != TREE_CODE (parm))
10158 /* We have already checked cv-qualification at the top of the
10160 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10163 /* As far as unification is concerned, this wins. Later checks
10164 will invalidate it if necessary. */
10167 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10168 /* Type INTEGER_CST can come from ordinary constant template args. */
10170 while (TREE_CODE (arg) == NOP_EXPR)
10171 arg = TREE_OPERAND (arg, 0);
10173 if (TREE_CODE (arg) != INTEGER_CST)
10175 return !tree_int_cst_equal (parm, arg);
10180 if (TREE_CODE (arg) != TREE_VEC)
10182 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10184 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10185 if (unify (tparms, targs,
10186 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10194 if (TREE_CODE (arg) != TREE_CODE (parm))
10197 if (TYPE_PTRMEMFUNC_P (parm))
10199 if (!TYPE_PTRMEMFUNC_P (arg))
10202 return unify (tparms, targs,
10203 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10204 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10208 if (CLASSTYPE_TEMPLATE_INFO (parm))
10210 tree t = NULL_TREE;
10212 if (strict_in & UNIFY_ALLOW_DERIVED)
10214 /* First, we try to unify the PARM and ARG directly. */
10215 t = try_class_unification (tparms, targs,
10220 /* Fallback to the special case allowed in
10221 [temp.deduct.call]:
10223 If P is a class, and P has the form
10224 template-id, then A can be a derived class of
10225 the deduced A. Likewise, if P is a pointer to
10226 a class of the form template-id, A can be a
10227 pointer to a derived class pointed to by the
10229 t = get_template_base (tparms, targs, parm, arg);
10235 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10236 && (CLASSTYPE_TI_TEMPLATE (parm)
10237 == CLASSTYPE_TI_TEMPLATE (arg)))
10238 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10239 Then, we should unify `int' and `U'. */
10242 /* There's no chance of unification succeeding. */
10245 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10246 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10248 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10253 case FUNCTION_TYPE:
10254 if (TREE_CODE (arg) != TREE_CODE (parm))
10257 if (unify (tparms, targs, TREE_TYPE (parm),
10258 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10260 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10261 TYPE_ARG_TYPES (arg), 1,
10262 DEDUCE_EXACT, 0, -1);
10265 if (TREE_CODE (arg) != OFFSET_TYPE)
10267 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10268 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10270 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10274 if (DECL_TEMPLATE_PARM_P (parm))
10275 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10276 if (arg != decl_constant_value (parm))
10281 case TEMPLATE_DECL:
10282 /* Matched cases are handled by the ARG == PARM test above. */
10286 gcc_assert (EXPR_P (parm));
10288 /* We must be looking at an expression. This can happen with
10292 void foo(S<I>, S<I + 2>);
10294 This is a "nondeduced context":
10298 The nondeduced contexts are:
10300 --A type that is a template-id in which one or more of
10301 the template-arguments is an expression that references
10302 a template-parameter.
10304 In these cases, we assume deduction succeeded, but don't
10305 actually infer any unifications. */
10307 if (!uses_template_parms (parm)
10308 && !template_args_equal (parm, arg))
10315 /* Note that DECL can be defined in this translation unit, if
10319 mark_definable (tree decl)
10322 DECL_NOT_REALLY_EXTERN (decl) = 1;
10323 FOR_EACH_CLONE (clone, decl)
10324 DECL_NOT_REALLY_EXTERN (clone) = 1;
10327 /* Called if RESULT is explicitly instantiated, or is a member of an
10328 explicitly instantiated class. */
10331 mark_decl_instantiated (tree result, int extern_p)
10333 SET_DECL_EXPLICIT_INSTANTIATION (result);
10335 /* If this entity has already been written out, it's too late to
10336 make any modifications. */
10337 if (TREE_ASM_WRITTEN (result))
10340 if (TREE_CODE (result) != FUNCTION_DECL)
10341 /* The TREE_PUBLIC flag for function declarations will have been
10342 set correctly by tsubst. */
10343 TREE_PUBLIC (result) = 1;
10345 /* This might have been set by an earlier implicit instantiation. */
10346 DECL_COMDAT (result) = 0;
10349 DECL_NOT_REALLY_EXTERN (result) = 0;
10352 mark_definable (result);
10353 /* Always make artificials weak. */
10354 if (DECL_ARTIFICIAL (result) && flag_weak)
10355 comdat_linkage (result);
10356 /* For WIN32 we also want to put explicit instantiations in
10357 linkonce sections. */
10358 else if (TREE_PUBLIC (result))
10359 maybe_make_one_only (result);
10362 /* If EXTERN_P, then this function will not be emitted -- unless
10363 followed by an explicit instantiation, at which point its linkage
10364 will be adjusted. If !EXTERN_P, then this function will be
10365 emitted here. In neither circumstance do we want
10366 import_export_decl to adjust the linkage. */
10367 DECL_INTERFACE_KNOWN (result) = 1;
10370 /* Given two function templates PAT1 and PAT2, return:
10372 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
10374 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10375 -1 if PAT2 is more specialized than PAT1.
10376 0 if neither is more specialized.
10378 LEN is passed through to fn_type_unification. */
10381 more_specialized (tree pat1, tree pat2, int deduce, int len)
10386 /* If template argument deduction succeeds, we substitute the
10387 resulting arguments into non-deduced contexts. While doing that,
10388 we must be aware that we may encounter dependent types. */
10389 ++processing_template_decl;
10390 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
10391 NULL_TREE, 0, deduce, len);
10395 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
10396 NULL_TREE, 0, deduce, len);
10399 --processing_template_decl;
10404 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10406 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10407 -1 if PAT2 is more specialized than PAT1.
10408 0 if neither is more specialized.
10410 FULL_ARGS is the full set of template arguments that triggers this
10411 partial ordering. */
10414 more_specialized_class (tree pat1, tree pat2, tree full_args)
10419 /* Just like what happens for functions, if we are ordering between
10420 different class template specializations, we may encounter dependent
10421 types in the arguments, and we need our dependency check functions
10422 to behave correctly. */
10423 ++processing_template_decl;
10424 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10425 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10429 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10430 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10433 --processing_template_decl;
10438 /* Return the template arguments that will produce the function signature
10439 DECL from the function template FN, with the explicit template
10440 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
10441 also match. Return NULL_TREE if no satisfactory arguments could be
10442 found. DEDUCE and LEN are passed through to fn_type_unification. */
10445 get_bindings_real (tree fn,
10447 tree explicit_args,
10452 int ntparms = DECL_NTPARMS (fn);
10453 tree targs = make_tree_vec (ntparms);
10455 tree decl_arg_types;
10458 /* Substitute the explicit template arguments into the type of DECL.
10459 The call to fn_type_unification will handle substitution into the
10461 decl_type = TREE_TYPE (decl);
10462 if (explicit_args && uses_template_parms (decl_type))
10465 tree converted_args;
10467 if (DECL_TEMPLATE_INFO (decl))
10468 tmpl = DECL_TI_TEMPLATE (decl);
10470 /* We can get here for some invalid specializations. */
10474 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10475 explicit_args, NULL_TREE,
10476 tf_none, /*require_all_arguments=*/0));
10477 if (converted_args == error_mark_node)
10480 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10481 if (decl_type == error_mark_node)
10485 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10486 /* Never do unification on the 'this' parameter. */
10487 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10488 decl_arg_types = TREE_CHAIN (decl_arg_types);
10490 i = fn_type_unification (fn, explicit_args, targs,
10492 (check_rettype || DECL_CONV_FN_P (fn)
10493 ? TREE_TYPE (decl_type) : NULL_TREE),
10502 /* For most uses, we want to check the return type. */
10505 get_bindings (tree fn, tree decl, tree explicit_args)
10507 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10510 /* But for resolve_overloaded_unification, we only care about the parameter
10514 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10516 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10519 /* Return the innermost template arguments that, when applied to a
10520 template specialization whose innermost template parameters are
10521 TPARMS, and whose specialization arguments are PARMS, yield the
10524 For example, suppose we have:
10526 template <class T, class U> struct S {};
10527 template <class T> struct S<T*, int> {};
10529 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10530 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10531 int}. The resulting vector will be {double}, indicating that `T'
10532 is bound to `double'. */
10535 get_class_bindings (tree tparms, tree parms, tree args)
10537 int i, ntparms = TREE_VEC_LENGTH (tparms);
10538 tree vec = make_tree_vec (ntparms);
10540 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10544 for (i = 0; i < ntparms; ++i)
10545 if (! TREE_VEC_ELT (vec, i))
10548 if (verify_class_unification (vec, parms, args))
10554 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10555 Pick the most specialized template, and return the corresponding
10556 instantiation, or if there is no corresponding instantiation, the
10557 template itself. If there is no most specialized template,
10558 error_mark_node is returned. If there are no templates at all,
10559 NULL_TREE is returned. */
10562 most_specialized_instantiation (tree instantiations)
10567 if (!instantiations)
10570 champ = instantiations;
10571 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10573 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10581 fn = TREE_CHAIN (fn);
10583 return error_mark_node;
10589 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10591 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10594 return error_mark_node;
10597 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10600 /* Return the most specialized of the list of templates in FNS that can
10601 produce an instantiation matching DECL, given the explicit template
10602 arguments EXPLICIT_ARGS. */
10605 most_specialized (tree fns, tree decl, tree explicit_args)
10607 tree candidates = NULL_TREE;
10610 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10612 tree candidate = TREE_VALUE (fn);
10614 args = get_bindings (candidate, decl, explicit_args);
10616 candidates = tree_cons (NULL_TREE, candidate, candidates);
10619 return most_specialized_instantiation (candidates);
10622 /* If DECL is a specialization of some template, return the most
10623 general such template. Otherwise, returns NULL_TREE.
10625 For example, given:
10627 template <class T> struct S { template <class U> void f(U); };
10629 if TMPL is `template <class U> void S<int>::f(U)' this will return
10630 the full template. This function will not trace past partial
10631 specializations, however. For example, given in addition:
10633 template <class T> struct S<T*> { template <class U> void f(U); };
10635 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10636 `template <class T> template <class U> S<T*>::f(U)'. */
10639 most_general_template (tree decl)
10641 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10642 an immediate specialization. */
10643 if (TREE_CODE (decl) == FUNCTION_DECL)
10645 if (DECL_TEMPLATE_INFO (decl)) {
10646 decl = DECL_TI_TEMPLATE (decl);
10648 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10649 template friend. */
10650 if (TREE_CODE (decl) != TEMPLATE_DECL)
10656 /* Look for more and more general templates. */
10657 while (DECL_TEMPLATE_INFO (decl))
10659 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10660 (See cp-tree.h for details.) */
10661 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10664 if (CLASS_TYPE_P (TREE_TYPE (decl))
10665 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10668 /* Stop if we run into an explicitly specialized class template. */
10669 if (!DECL_NAMESPACE_SCOPE_P (decl)
10670 && DECL_CONTEXT (decl)
10671 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10674 decl = DECL_TI_TEMPLATE (decl);
10680 /* Return the most specialized of the class template specializations
10681 of TMPL which can produce an instantiation matching ARGS, or
10682 error_mark_node if the choice is ambiguous. */
10685 most_specialized_class (tree tmpl, tree args)
10687 tree list = NULL_TREE;
10692 tmpl = most_general_template (tmpl);
10693 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10696 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10699 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10700 TREE_TYPE (list) = TREE_TYPE (t);
10709 t = TREE_CHAIN (t);
10710 for (; t; t = TREE_CHAIN (t))
10712 fate = more_specialized_class (champ, t, args);
10719 t = TREE_CHAIN (t);
10721 return error_mark_node;
10727 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10729 fate = more_specialized_class (champ, t, args);
10731 return error_mark_node;
10737 /* Explicitly instantiate DECL. */
10740 do_decl_instantiation (tree decl, tree storage)
10742 tree result = NULL_TREE;
10746 /* An error occurred, for which grokdeclarator has already issued
10747 an appropriate message. */
10749 else if (! DECL_LANG_SPECIFIC (decl))
10751 error ("explicit instantiation of non-template %q#D", decl);
10754 else if (TREE_CODE (decl) == VAR_DECL)
10756 /* There is an asymmetry here in the way VAR_DECLs and
10757 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10758 the latter, the DECL we get back will be marked as a
10759 template instantiation, and the appropriate
10760 DECL_TEMPLATE_INFO will be set up. This does not happen for
10761 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10762 should handle VAR_DECLs as it currently handles
10764 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10765 if (!result || TREE_CODE (result) != VAR_DECL)
10767 error ("no matching template for %qD found", decl);
10771 else if (TREE_CODE (decl) != FUNCTION_DECL)
10773 error ("explicit instantiation of %q#D", decl);
10779 /* Check for various error cases. Note that if the explicit
10780 instantiation is valid the RESULT will currently be marked as an
10781 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10782 until we get here. */
10784 if (DECL_TEMPLATE_SPECIALIZATION (result))
10786 /* DR 259 [temp.spec].
10788 Both an explicit instantiation and a declaration of an explicit
10789 specialization shall not appear in a program unless the explicit
10790 instantiation follows a declaration of the explicit specialization.
10792 For a given set of template parameters, if an explicit
10793 instantiation of a template appears after a declaration of an
10794 explicit specialization for that template, the explicit
10795 instantiation has no effect. */
10798 else if (DECL_EXPLICIT_INSTANTIATION (result))
10802 No program shall explicitly instantiate any template more
10805 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10806 the first instantiation was `extern' and the second is not,
10807 and EXTERN_P for the opposite case. */
10808 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10809 pedwarn ("duplicate explicit instantiation of %q#D", result);
10810 /* If an "extern" explicit instantiation follows an ordinary
10811 explicit instantiation, the template is instantiated. */
10815 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10817 error ("no matching template for %qD found", result);
10820 else if (!DECL_TEMPLATE_INFO (result))
10822 pedwarn ("explicit instantiation of non-template %q#D", result);
10826 if (storage == NULL_TREE)
10828 else if (storage == ridpointers[(int) RID_EXTERN])
10830 if (pedantic && !in_system_header)
10831 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
10836 error ("storage class %qD applied to template instantiation", storage);
10838 mark_decl_instantiated (result, extern_p);
10840 instantiate_decl (result, /*defer_ok=*/1, /*undefined_ok=*/0);
10844 mark_class_instantiated (tree t, int extern_p)
10846 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10847 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10848 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10849 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10852 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10853 rest_of_type_compilation (t, 1);
10857 /* Called from do_type_instantiation through binding_table_foreach to
10858 do recursive instantiation for the type bound in ENTRY. */
10860 bt_instantiate_type_proc (binding_entry entry, void *data)
10862 tree storage = *(tree *) data;
10864 if (IS_AGGR_TYPE (entry->type)
10865 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10866 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10869 /* Called from do_type_instantiation to instantiate a member
10870 (a member function or a static member variable) of an
10871 explicitly instantiated class template. */
10873 instantiate_class_member (tree decl, int extern_p)
10875 mark_decl_instantiated (decl, extern_p);
10877 instantiate_decl (decl, /*defer_ok=*/1, /* undefined_ok=*/1);
10880 /* Perform an explicit instantiation of template class T. STORAGE, if
10881 non-null, is the RID for extern, inline or static. COMPLAIN is
10882 nonzero if this is called from the parser, zero if called recursively,
10883 since the standard is unclear (as detailed below). */
10886 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10891 int previous_instantiation_extern_p = 0;
10893 if (TREE_CODE (t) == TYPE_DECL)
10896 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10898 error ("explicit instantiation of non-template type %qT", t);
10904 if (!COMPLETE_TYPE_P (t))
10906 if (complain & tf_error)
10907 error ("explicit instantiation of %q#T before definition of template",
10912 if (storage != NULL_TREE)
10914 if (pedantic && !in_system_header)
10915 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
10918 if (storage == ridpointers[(int) RID_INLINE])
10920 else if (storage == ridpointers[(int) RID_EXTERN])
10922 else if (storage == ridpointers[(int) RID_STATIC])
10926 error ("storage class %qD applied to template instantiation",
10932 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10934 /* DR 259 [temp.spec].
10936 Both an explicit instantiation and a declaration of an explicit
10937 specialization shall not appear in a program unless the explicit
10938 instantiation follows a declaration of the explicit specialization.
10940 For a given set of template parameters, if an explicit
10941 instantiation of a template appears after a declaration of an
10942 explicit specialization for that template, the explicit
10943 instantiation has no effect. */
10946 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10950 No program shall explicitly instantiate any template more
10953 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
10954 instantiation was `extern'. If EXTERN_P then the second is.
10955 These cases are OK. */
10956 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
10958 if (!previous_instantiation_extern_p && !extern_p
10959 && (complain & tf_error))
10960 pedwarn ("duplicate explicit instantiation of %q#T", t);
10962 /* If we've already instantiated the template, just return now. */
10963 if (!CLASSTYPE_INTERFACE_ONLY (t))
10967 mark_class_instantiated (t, extern_p);
10975 /* In contrast to implicit instantiation, where only the
10976 declarations, and not the definitions, of members are
10977 instantiated, we have here:
10981 The explicit instantiation of a class template specialization
10982 implies the instantiation of all of its members not
10983 previously explicitly specialized in the translation unit
10984 containing the explicit instantiation.
10986 Of course, we can't instantiate member template classes, since
10987 we don't have any arguments for them. Note that the standard
10988 is unclear on whether the instantiation of the members are
10989 *explicit* instantiations or not. However, the most natural
10990 interpretation is that it should be an explicit instantiation. */
10993 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
10994 if (TREE_CODE (tmp) == FUNCTION_DECL
10995 && DECL_TEMPLATE_INSTANTIATION (tmp))
10996 instantiate_class_member (tmp, extern_p);
10998 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
10999 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11000 instantiate_class_member (tmp, extern_p);
11002 if (CLASSTYPE_NESTED_UTDS (t))
11003 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11004 bt_instantiate_type_proc, &storage);
11008 /* Given a function DECL, which is a specialization of TMPL, modify
11009 DECL to be a re-instantiation of TMPL with the same template
11010 arguments. TMPL should be the template into which tsubst'ing
11011 should occur for DECL, not the most general template.
11013 One reason for doing this is a scenario like this:
11016 void f(const T&, int i);
11018 void g() { f(3, 7); }
11021 void f(const T& t, const int i) { }
11023 Note that when the template is first instantiated, with
11024 instantiate_template, the resulting DECL will have no name for the
11025 first parameter, and the wrong type for the second. So, when we go
11026 to instantiate the DECL, we regenerate it. */
11029 regenerate_decl_from_template (tree decl, tree tmpl)
11031 /* The arguments used to instantiate DECL, from the most general
11036 args = DECL_TI_ARGS (decl);
11037 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11039 /* Make sure that we can see identifiers, and compute access
11041 push_access_scope (decl);
11043 if (TREE_CODE (decl) == FUNCTION_DECL)
11051 args_depth = TMPL_ARGS_DEPTH (args);
11052 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11053 if (args_depth > parms_depth)
11054 args = get_innermost_template_args (args, parms_depth);
11056 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11057 args, tf_error, NULL_TREE);
11059 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11062 /* Merge parameter declarations. */
11063 decl_parm = skip_artificial_parms_for (decl,
11064 DECL_ARGUMENTS (decl));
11066 = skip_artificial_parms_for (code_pattern,
11067 DECL_ARGUMENTS (code_pattern));
11072 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11073 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11074 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11076 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11077 TREE_TYPE (decl_parm) = parm_type;
11078 decl_parm = TREE_CHAIN (decl_parm);
11079 pattern_parm = TREE_CHAIN (pattern_parm);
11082 /* Merge additional specifiers from the CODE_PATTERN. */
11083 if (DECL_DECLARED_INLINE_P (code_pattern)
11084 && !DECL_DECLARED_INLINE_P (decl))
11085 DECL_DECLARED_INLINE_P (decl) = 1;
11086 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11087 DECL_INLINE (decl) = 1;
11089 else if (TREE_CODE (decl) == VAR_DECL)
11091 if (!DECL_INITIALIZED_IN_CLASS_P (decl)
11092 && DECL_INITIAL (code_pattern))
11093 DECL_INITIAL (decl) =
11094 tsubst_expr (DECL_INITIAL (code_pattern), args,
11095 tf_error, DECL_TI_TEMPLATE (decl));
11098 gcc_unreachable ();
11100 pop_access_scope (decl);
11103 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11104 substituted to get DECL. */
11107 template_for_substitution (tree decl)
11109 tree tmpl = DECL_TI_TEMPLATE (decl);
11111 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11112 for the instantiation. This is not always the most general
11113 template. Consider, for example:
11116 struct S { template <class U> void f();
11117 template <> void f<int>(); };
11119 and an instantiation of S<double>::f<int>. We want TD to be the
11120 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11121 while (/* An instantiation cannot have a definition, so we need a
11122 more general template. */
11123 DECL_TEMPLATE_INSTANTIATION (tmpl)
11124 /* We must also deal with friend templates. Given:
11126 template <class T> struct S {
11127 template <class U> friend void f() {};
11130 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11131 so far as the language is concerned, but that's still
11132 where we get the pattern for the instantiation from. On
11133 other hand, if the definition comes outside the class, say:
11135 template <class T> struct S {
11136 template <class U> friend void f();
11138 template <class U> friend void f() {}
11140 we don't need to look any further. That's what the check for
11141 DECL_INITIAL is for. */
11142 || (TREE_CODE (decl) == FUNCTION_DECL
11143 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11144 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11146 /* The present template, TD, should not be a definition. If it
11147 were a definition, we should be using it! Note that we
11148 cannot restructure the loop to just keep going until we find
11149 a template with a definition, since that might go too far if
11150 a specialization was declared, but not defined. */
11151 gcc_assert (TREE_CODE (decl) != VAR_DECL
11152 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11154 /* Fetch the more general template. */
11155 tmpl = DECL_TI_TEMPLATE (tmpl);
11161 /* Produce the definition of D, a _DECL generated from a template. If
11162 DEFER_OK is nonzero, then we don't have to actually do the
11163 instantiation now; we just have to do it sometime. Normally it is
11164 an error if this is an explicit instantiation but D is undefined.
11165 If UNDEFINED_OK is nonzero, then instead we treat it as an implicit
11166 instantiation. UNDEFINED_OK is nonzero only if we are being used
11167 to instantiate the members of an explicitly instantiated class
11172 instantiate_decl (tree d, int defer_ok, int undefined_ok)
11174 tree tmpl = DECL_TI_TEMPLATE (d);
11181 int pattern_defined;
11183 location_t saved_loc = input_location;
11185 /* This function should only be used to instantiate templates for
11186 functions and static member variables. */
11187 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11188 || TREE_CODE (d) == VAR_DECL);
11190 /* Variables are never deferred; if instantiation is required, they
11191 are instantiated right away. That allows for better code in the
11192 case that an expression refers to the value of the variable --
11193 if the variable has a constant value the referring expression can
11194 take advantage of that fact. */
11195 if (TREE_CODE (d) == VAR_DECL)
11198 /* Don't instantiate cloned functions. Instead, instantiate the
11199 functions they cloned. */
11200 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11201 d = DECL_CLONED_FUNCTION (d);
11203 if (DECL_TEMPLATE_INSTANTIATED (d))
11204 /* D has already been instantiated. It might seem reasonable to
11205 check whether or not D is an explicit instantiation, and, if so,
11206 stop here. But when an explicit instantiation is deferred
11207 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11208 is set, even though we still need to do the instantiation. */
11211 /* If we already have a specialization of this declaration, then
11212 there's no reason to instantiate it. Note that
11213 retrieve_specialization gives us both instantiations and
11214 specializations, so we must explicitly check
11215 DECL_TEMPLATE_SPECIALIZATION. */
11216 gen_tmpl = most_general_template (tmpl);
11217 gen_args = DECL_TI_ARGS (d);
11218 spec = retrieve_specialization (gen_tmpl, gen_args,
11219 /*class_specializations_p=*/false);
11220 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11223 /* This needs to happen before any tsubsting. */
11224 if (! push_tinst_level (d))
11227 timevar_push (TV_PARSE);
11229 /* We may be in the middle of deferred access check. Disable it now. */
11230 push_deferring_access_checks (dk_no_deferred);
11232 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11233 for the instantiation. */
11234 td = template_for_substitution (d);
11235 code_pattern = DECL_TEMPLATE_RESULT (td);
11237 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11238 || DECL_TEMPLATE_SPECIALIZATION (td))
11239 /* In the case of a friend template whose definition is provided
11240 outside the class, we may have too many arguments. Drop the
11241 ones we don't need. The same is true for specializations. */
11242 args = get_innermost_template_args
11243 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11247 if (TREE_CODE (d) == FUNCTION_DECL)
11248 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11250 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11251 /* Unless an explicit instantiation directive has already determined
11252 the linkage of D, remember that a definition is available for
11254 if (pattern_defined
11255 && !DECL_INTERFACE_KNOWN (d)
11256 && !DECL_NOT_REALLY_EXTERN (d))
11257 mark_definable (d);
11259 input_location = DECL_SOURCE_LOCATION (d);
11261 if (! pattern_defined && DECL_EXPLICIT_INSTANTIATION (d) && undefined_ok)
11263 DECL_NOT_REALLY_EXTERN (d) = 0;
11264 SET_DECL_IMPLICIT_INSTANTIATION (d);
11269 /* Recheck the substitutions to obtain any warning messages
11270 about ignoring cv qualifiers. */
11271 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11272 tree type = TREE_TYPE (gen);
11274 /* Make sure that we can see identifiers, and compute access
11275 correctly. D is already the target FUNCTION_DECL with the
11277 push_access_scope (d);
11279 if (TREE_CODE (gen) == FUNCTION_DECL)
11281 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11282 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11283 tf_error | tf_warning, d);
11284 /* Don't simply tsubst the function type, as that will give
11285 duplicate warnings about poor parameter qualifications.
11286 The function arguments are the same as the decl_arguments
11287 without the top level cv qualifiers. */
11288 type = TREE_TYPE (type);
11290 tsubst (type, gen_args, tf_error | tf_warning, d);
11292 pop_access_scope (d);
11295 /* We should have set up DECL_INITIAL in instantiate_class_template
11296 for in-class definitions of static data members. */
11297 gcc_assert (!(TREE_CODE (d) == VAR_DECL
11298 && DECL_INITIALIZED_IN_CLASS_P (d)
11299 && DECL_INITIAL (d) == NULL_TREE));
11301 /* Do not instantiate templates that we know will be defined
11303 if (DECL_INTERFACE_KNOWN (d)
11304 && DECL_REALLY_EXTERN (d)
11305 && ! (TREE_CODE (d) == FUNCTION_DECL
11306 && DECL_INLINE (d)))
11308 /* Defer all other templates, unless we have been explicitly
11309 forbidden from doing so. We restore the source position here
11310 because it's used by add_pending_template. */
11311 else if (! pattern_defined || defer_ok)
11313 input_location = saved_loc;
11315 if (at_eof && !pattern_defined
11316 && DECL_EXPLICIT_INSTANTIATION (d))
11319 The definition of a non-exported function template, a
11320 non-exported member function template, or a non-exported
11321 member function or static data member of a class template
11322 shall be present in every translation unit in which it is
11323 explicitly instantiated. */
11325 ("explicit instantiation of %qD but no definition available", d);
11327 add_pending_template (d);
11330 /* Tell the repository that D is available in this translation unit
11331 -- and see if it is supposed to be instantiated here. */
11332 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11334 /* In a PCH file, despite the fact that the repository hasn't
11335 requested instantiation in the PCH it is still possible that
11336 an instantiation will be required in a file that includes the
11339 add_pending_template (d);
11340 /* Instantiate inline functions so that the inliner can do its
11341 job, even though we'll not be emitting a copy of this
11343 if (!(TREE_CODE (d) == FUNCTION_DECL
11344 && flag_inline_trees
11345 && DECL_DECLARED_INLINE_P (d)))
11349 need_push = !cfun || !global_bindings_p ();
11351 push_to_top_level ();
11353 /* Mark D as instantiated so that recursive calls to
11354 instantiate_decl do not try to instantiate it again. */
11355 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11357 /* Regenerate the declaration in case the template has been modified
11358 by a subsequent redeclaration. */
11359 regenerate_decl_from_template (d, td);
11361 /* We already set the file and line above. Reset them now in case
11362 they changed as a result of calling regenerate_decl_from_template. */
11363 input_location = DECL_SOURCE_LOCATION (d);
11365 if (TREE_CODE (d) == VAR_DECL)
11367 /* Clear out DECL_RTL; whatever was there before may not be right
11368 since we've reset the type of the declaration. */
11369 SET_DECL_RTL (d, NULL_RTX);
11370 DECL_IN_AGGR_P (d) = 0;
11372 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11373 initializer. That function will defer actual emission until
11374 we have a chance to determine linkage. */
11375 DECL_EXTERNAL (d) = 0;
11377 /* Enter the scope of D so that access-checking works correctly. */
11378 push_nested_class (DECL_CONTEXT (d));
11380 (!DECL_INITIALIZED_IN_CLASS_P (d)
11381 ? DECL_INITIAL (d) : NULL_TREE),
11383 pop_nested_class ();
11385 else if (TREE_CODE (d) == FUNCTION_DECL)
11387 htab_t saved_local_specializations;
11392 /* Save away the current list, in case we are instantiating one
11393 template from within the body of another. */
11394 saved_local_specializations = local_specializations;
11396 /* Set up the list of local specializations. */
11397 local_specializations = htab_create (37,
11398 hash_local_specialization,
11399 eq_local_specializations,
11402 /* Set up context. */
11403 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11405 /* Create substitution entries for the parameters. */
11406 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11407 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11408 spec_parm = DECL_ARGUMENTS (d);
11409 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11411 register_local_specialization (spec_parm, tmpl_parm);
11412 spec_parm = skip_artificial_parms_for (d, spec_parm);
11413 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11417 register_local_specialization (spec_parm, tmpl_parm);
11418 tmpl_parm = TREE_CHAIN (tmpl_parm);
11419 spec_parm = TREE_CHAIN (spec_parm);
11421 gcc_assert (!spec_parm);
11423 /* Substitute into the body of the function. */
11424 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11425 tf_error | tf_warning, tmpl);
11427 /* We don't need the local specializations any more. */
11428 htab_delete (local_specializations);
11429 local_specializations = saved_local_specializations;
11431 /* Finish the function. */
11432 d = finish_function (0);
11433 expand_or_defer_fn (d);
11436 /* We're not deferring instantiation any more. */
11437 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11440 pop_from_top_level ();
11443 input_location = saved_loc;
11444 pop_deferring_access_checks ();
11445 pop_tinst_level ();
11447 timevar_pop (TV_PARSE);
11452 /* Run through the list of templates that we wish we could
11453 instantiate, and instantiate any we can. RETRIES is the
11454 number of times we retry pending template instantiation. */
11457 instantiate_pending_templates (int retries)
11460 tree last = NULL_TREE;
11462 location_t saved_loc = input_location;
11464 /* Instantiating templates may trigger vtable generation. This in turn
11465 may require further template instantiations. We place a limit here
11466 to avoid infinite loop. */
11467 if (pending_templates && retries >= max_tinst_depth)
11469 cp_error_at ("template instantiation depth exceeds maximum of %d"
11470 " (use -ftemplate-depth-NN to increase the maximum)"
11471 " instantiating %q+D, possibly from virtual table"
11473 max_tinst_depth, TREE_VALUE (pending_templates));
11481 t = &pending_templates;
11484 tree instantiation = TREE_VALUE (*t);
11486 reopen_tinst_level (TREE_PURPOSE (*t));
11488 if (TYPE_P (instantiation))
11492 if (!COMPLETE_TYPE_P (instantiation))
11494 instantiate_class_template (instantiation);
11495 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11496 for (fn = TYPE_METHODS (instantiation);
11498 fn = TREE_CHAIN (fn))
11499 if (! DECL_ARTIFICIAL (fn))
11500 instantiate_decl (fn, /*defer_ok=*/0,
11501 /*undefined_ok=*/0);
11502 if (COMPLETE_TYPE_P (instantiation))
11506 if (COMPLETE_TYPE_P (instantiation))
11507 /* If INSTANTIATION has been instantiated, then we don't
11508 need to consider it again in the future. */
11509 *t = TREE_CHAIN (*t);
11513 t = &TREE_CHAIN (*t);
11518 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11519 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11521 instantiation = instantiate_decl (instantiation,
11523 /*undefined_ok=*/0);
11524 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11528 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11529 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11530 /* If INSTANTIATION has been instantiated, then we don't
11531 need to consider it again in the future. */
11532 *t = TREE_CHAIN (*t);
11536 t = &TREE_CHAIN (*t);
11540 current_tinst_level = NULL_TREE;
11542 last_pending_template = last;
11544 while (reconsider);
11546 input_location = saved_loc;
11549 /* Substitute ARGVEC into T, which is a list of initializers for
11550 either base class or a non-static data member. The TREE_PURPOSEs
11551 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11552 instantiate_decl. */
11555 tsubst_initializer_list (tree t, tree argvec)
11557 tree inits = NULL_TREE;
11559 for (; t; t = TREE_CHAIN (t))
11565 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11567 decl = expand_member_init (decl);
11568 if (decl && !DECL_P (decl))
11569 in_base_initializer = 1;
11571 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11575 else if (TREE_CODE (init) == TREE_LIST)
11576 for (val = init; val; val = TREE_CHAIN (val))
11577 TREE_VALUE (val) = convert_from_reference (TREE_VALUE (val));
11578 else if (init != void_type_node)
11579 init = convert_from_reference (init);
11581 in_base_initializer = 0;
11585 init = build_tree_list (decl, init);
11586 TREE_CHAIN (init) = inits;
11593 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11596 set_current_access_from_decl (tree decl)
11598 if (TREE_PRIVATE (decl))
11599 current_access_specifier = access_private_node;
11600 else if (TREE_PROTECTED (decl))
11601 current_access_specifier = access_protected_node;
11603 current_access_specifier = access_public_node;
11606 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11607 is the instantiation (which should have been created with
11608 start_enum) and ARGS are the template arguments to use. */
11611 tsubst_enum (tree tag, tree newtag, tree args)
11615 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11620 decl = TREE_VALUE (e);
11621 /* Note that in a template enum, the TREE_VALUE is the
11622 CONST_DECL, not the corresponding INTEGER_CST. */
11623 value = tsubst_expr (DECL_INITIAL (decl),
11624 args, tf_error | tf_warning,
11627 /* Give this enumeration constant the correct access. */
11628 set_current_access_from_decl (decl);
11630 /* Actually build the enumerator itself. */
11631 build_enumerator (DECL_NAME (decl), value, newtag);
11634 finish_enum (newtag);
11635 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11636 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11639 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11640 its type -- but without substituting the innermost set of template
11641 arguments. So, innermost set of template parameters will appear in
11645 get_mostly_instantiated_function_type (tree decl)
11653 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11654 targs = DECL_TI_ARGS (decl);
11655 tparms = DECL_TEMPLATE_PARMS (tmpl);
11656 parm_depth = TMPL_PARMS_DEPTH (tparms);
11658 /* There should be as many levels of arguments as there are levels
11660 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11662 fn_type = TREE_TYPE (tmpl);
11664 if (parm_depth == 1)
11665 /* No substitution is necessary. */
11672 /* Replace the innermost level of the TARGS with NULL_TREEs to
11673 let tsubst know not to substitute for those parameters. */
11674 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11675 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11676 SET_TMPL_ARGS_LEVEL (partial_args, i,
11677 TMPL_ARGS_LEVEL (targs, i));
11678 SET_TMPL_ARGS_LEVEL (partial_args,
11679 TMPL_ARGS_DEPTH (targs),
11680 make_tree_vec (DECL_NTPARMS (tmpl)));
11682 /* Make sure that we can see identifiers, and compute access
11683 correctly. We can just use the context of DECL for the
11684 partial substitution here. It depends only on outer template
11685 parameters, regardless of whether the innermost level is
11686 specialized or not. */
11687 push_access_scope (decl);
11689 ++processing_template_decl;
11690 /* Now, do the (partial) substitution to figure out the
11691 appropriate function type. */
11692 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11693 --processing_template_decl;
11695 /* Substitute into the template parameters to obtain the real
11696 innermost set of parameters. This step is important if the
11697 innermost set of template parameters contains value
11698 parameters whose types depend on outer template parameters. */
11699 TREE_VEC_LENGTH (partial_args)--;
11700 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11702 pop_access_scope (decl);
11708 /* Return truthvalue if we're processing a template different from
11709 the last one involved in diagnostics. */
11711 problematic_instantiation_changed (void)
11713 return last_template_error_tick != tinst_level_tick;
11716 /* Remember current template involved in diagnostics. */
11718 record_last_problematic_instantiation (void)
11720 last_template_error_tick = tinst_level_tick;
11724 current_instantiation (void)
11726 return current_tinst_level;
11729 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11730 type. Return zero for ok, nonzero for disallowed. Issue error and
11731 warning messages under control of COMPLAIN. */
11734 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11736 if (INTEGRAL_TYPE_P (type))
11738 else if (POINTER_TYPE_P (type))
11740 else if (TYPE_PTR_TO_MEMBER_P (type))
11742 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11744 else if (TREE_CODE (type) == TYPENAME_TYPE)
11747 if (complain & tf_error)
11748 error ("%q#T is not a valid type for a template constant parameter", type);
11752 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11753 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11756 dependent_type_p_r (tree type)
11762 A type is dependent if it is:
11764 -- a template parameter. Template template parameters are types
11765 for us (since TYPE_P holds true for them) so we handle
11767 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11768 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11770 /* -- a qualified-id with a nested-name-specifier which contains a
11771 class-name that names a dependent type or whose unqualified-id
11772 names a dependent type. */
11773 if (TREE_CODE (type) == TYPENAME_TYPE)
11775 /* -- a cv-qualified type where the cv-unqualified type is
11777 type = TYPE_MAIN_VARIANT (type);
11778 /* -- a compound type constructed from any dependent type. */
11779 if (TYPE_PTR_TO_MEMBER_P (type))
11780 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11781 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11783 else if (TREE_CODE (type) == POINTER_TYPE
11784 || TREE_CODE (type) == REFERENCE_TYPE)
11785 return dependent_type_p (TREE_TYPE (type));
11786 else if (TREE_CODE (type) == FUNCTION_TYPE
11787 || TREE_CODE (type) == METHOD_TYPE)
11791 if (dependent_type_p (TREE_TYPE (type)))
11793 for (arg_type = TYPE_ARG_TYPES (type);
11795 arg_type = TREE_CHAIN (arg_type))
11796 if (dependent_type_p (TREE_VALUE (arg_type)))
11800 /* -- an array type constructed from any dependent type or whose
11801 size is specified by a constant expression that is
11802 value-dependent. */
11803 if (TREE_CODE (type) == ARRAY_TYPE)
11805 if (TYPE_DOMAIN (type)
11806 && ((value_dependent_expression_p
11807 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11808 || (type_dependent_expression_p
11809 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11811 return dependent_type_p (TREE_TYPE (type));
11814 /* -- a template-id in which either the template name is a template
11816 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11818 /* ... or any of the template arguments is a dependent type or
11819 an expression that is type-dependent or value-dependent. */
11820 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11821 && (any_dependent_template_arguments_p
11822 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11825 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11826 expression is not type-dependent, then it should already been
11828 if (TREE_CODE (type) == TYPEOF_TYPE)
11831 /* The standard does not specifically mention types that are local
11832 to template functions or local classes, but they should be
11833 considered dependent too. For example:
11835 template <int I> void f() {
11840 The size of `E' cannot be known until the value of `I' has been
11841 determined. Therefore, `E' must be considered dependent. */
11842 scope = TYPE_CONTEXT (type);
11843 if (scope && TYPE_P (scope))
11844 return dependent_type_p (scope);
11845 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11846 return type_dependent_expression_p (scope);
11848 /* Other types are non-dependent. */
11852 /* Returns TRUE if TYPE is dependent, in the sense of
11853 [temp.dep.type]. */
11856 dependent_type_p (tree type)
11858 /* If there are no template parameters in scope, then there can't be
11859 any dependent types. */
11860 if (!processing_template_decl)
11863 /* If the type is NULL, we have not computed a type for the entity
11864 in question; in that case, the type is dependent. */
11868 /* Erroneous types can be considered non-dependent. */
11869 if (type == error_mark_node)
11872 /* If we have not already computed the appropriate value for TYPE,
11874 if (!TYPE_DEPENDENT_P_VALID (type))
11876 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11877 TYPE_DEPENDENT_P_VALID (type) = 1;
11880 return TYPE_DEPENDENT_P (type);
11883 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11886 dependent_scope_ref_p (tree expression, bool criterion (tree))
11891 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
11893 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11896 scope = TREE_OPERAND (expression, 0);
11897 name = TREE_OPERAND (expression, 1);
11901 An id-expression is type-dependent if it contains a
11902 nested-name-specifier that contains a class-name that names a
11904 /* The suggested resolution to Core Issue 2 implies that if the
11905 qualifying type is the current class, then we must peek
11908 && currently_open_class (scope)
11909 && !criterion (name))
11911 if (dependent_type_p (scope))
11917 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11918 [temp.dep.constexpr] */
11921 value_dependent_expression_p (tree expression)
11923 if (!processing_template_decl)
11926 /* A name declared with a dependent type. */
11927 if (TREE_CODE (expression) == IDENTIFIER_NODE
11928 || (DECL_P (expression)
11929 && type_dependent_expression_p (expression)))
11931 /* A non-type template parameter. */
11932 if ((TREE_CODE (expression) == CONST_DECL
11933 && DECL_TEMPLATE_PARM_P (expression))
11934 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11936 /* A constant with integral or enumeration type and is initialized
11937 with an expression that is value-dependent. */
11938 if (TREE_CODE (expression) == VAR_DECL
11939 && DECL_INITIAL (expression)
11940 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11941 && value_dependent_expression_p (DECL_INITIAL (expression)))
11943 /* These expressions are value-dependent if the type to which the
11944 cast occurs is dependent or the expression being casted is
11945 value-dependent. */
11946 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11947 || TREE_CODE (expression) == STATIC_CAST_EXPR
11948 || TREE_CODE (expression) == CONST_CAST_EXPR
11949 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11950 || TREE_CODE (expression) == CAST_EXPR)
11952 tree type = TREE_TYPE (expression);
11953 if (dependent_type_p (type))
11955 /* A functional cast has a list of operands. */
11956 expression = TREE_OPERAND (expression, 0);
11959 /* If there are no operands, it must be an expression such
11960 as "int()". This should not happen for aggregate types
11961 because it would form non-constant expressions. */
11962 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
11966 if (TREE_CODE (expression) == TREE_LIST)
11970 if (value_dependent_expression_p (TREE_VALUE (expression)))
11972 expression = TREE_CHAIN (expression);
11974 while (expression);
11978 return value_dependent_expression_p (expression);
11980 /* A `sizeof' expression is value-dependent if the operand is
11982 if (TREE_CODE (expression) == SIZEOF_EXPR
11983 || TREE_CODE (expression) == ALIGNOF_EXPR)
11985 expression = TREE_OPERAND (expression, 0);
11986 if (TYPE_P (expression))
11987 return dependent_type_p (expression);
11988 return type_dependent_expression_p (expression);
11990 if (TREE_CODE (expression) == SCOPE_REF)
11991 return dependent_scope_ref_p (expression, value_dependent_expression_p);
11992 if (TREE_CODE (expression) == COMPONENT_REF)
11993 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
11994 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
11995 /* A constant expression is value-dependent if any subexpression is
11996 value-dependent. */
11997 if (EXPR_P (expression))
11999 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12002 return (value_dependent_expression_p
12003 (TREE_OPERAND (expression, 0)));
12004 case tcc_comparison:
12006 return ((value_dependent_expression_p
12007 (TREE_OPERAND (expression, 0)))
12008 || (value_dependent_expression_p
12009 (TREE_OPERAND (expression, 1))));
12010 case tcc_expression:
12013 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12014 /* In some cases, some of the operands may be missing.
12015 (For example, in the case of PREDECREMENT_EXPR, the
12016 amount to increment by may be missing.) That doesn't
12017 make the expression dependent. */
12018 if (TREE_OPERAND (expression, i)
12019 && (value_dependent_expression_p
12020 (TREE_OPERAND (expression, i))))
12024 case tcc_reference:
12025 case tcc_statement:
12026 /* These cannot be value dependent. */
12030 gcc_unreachable ();
12034 /* The expression is not value-dependent. */
12038 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12039 [temp.dep.expr]. */
12042 type_dependent_expression_p (tree expression)
12044 if (!processing_template_decl)
12047 if (expression == error_mark_node)
12050 /* An unresolved name is always dependent. */
12051 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12054 /* Some expression forms are never type-dependent. */
12055 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12056 || TREE_CODE (expression) == SIZEOF_EXPR
12057 || TREE_CODE (expression) == ALIGNOF_EXPR
12058 || TREE_CODE (expression) == TYPEID_EXPR
12059 || TREE_CODE (expression) == DELETE_EXPR
12060 || TREE_CODE (expression) == VEC_DELETE_EXPR
12061 || TREE_CODE (expression) == THROW_EXPR)
12064 /* The types of these expressions depends only on the type to which
12065 the cast occurs. */
12066 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12067 || TREE_CODE (expression) == STATIC_CAST_EXPR
12068 || TREE_CODE (expression) == CONST_CAST_EXPR
12069 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12070 || TREE_CODE (expression) == CAST_EXPR)
12071 return dependent_type_p (TREE_TYPE (expression));
12073 /* The types of these expressions depends only on the type created
12074 by the expression. */
12075 if (TREE_CODE (expression) == NEW_EXPR
12076 || TREE_CODE (expression) == VEC_NEW_EXPR)
12078 /* For NEW_EXPR tree nodes created inside a template, either
12079 the object type itself or a TREE_LIST may appear as the
12081 tree type = TREE_OPERAND (expression, 1);
12082 if (TREE_CODE (type) == TREE_LIST)
12083 /* This is an array type. We need to check array dimensions
12085 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12086 || value_dependent_expression_p
12087 (TREE_OPERAND (TREE_VALUE (type), 1));
12089 return dependent_type_p (type);
12092 if (TREE_CODE (expression) == SCOPE_REF
12093 && dependent_scope_ref_p (expression,
12094 type_dependent_expression_p))
12097 if (TREE_CODE (expression) == FUNCTION_DECL
12098 && DECL_LANG_SPECIFIC (expression)
12099 && DECL_TEMPLATE_INFO (expression)
12100 && (any_dependent_template_arguments_p
12101 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12104 if (TREE_CODE (expression) == TEMPLATE_DECL
12105 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12108 if (TREE_TYPE (expression) == unknown_type_node)
12110 if (TREE_CODE (expression) == ADDR_EXPR)
12111 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12112 if (TREE_CODE (expression) == COMPONENT_REF
12113 || TREE_CODE (expression) == OFFSET_REF)
12115 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12117 expression = TREE_OPERAND (expression, 1);
12118 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12121 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12122 if (TREE_CODE (expression) == SCOPE_REF)
12125 if (TREE_CODE (expression) == BASELINK)
12126 expression = BASELINK_FUNCTIONS (expression);
12128 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12130 if (any_dependent_template_arguments_p
12131 (TREE_OPERAND (expression, 1)))
12133 expression = TREE_OPERAND (expression, 0);
12135 gcc_assert (TREE_CODE (expression) == OVERLOAD);
12139 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12141 expression = OVL_NEXT (expression);
12146 return (dependent_type_p (TREE_TYPE (expression)));
12149 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12150 contains a type-dependent expression. */
12153 any_type_dependent_arguments_p (tree args)
12157 tree arg = TREE_VALUE (args);
12159 if (type_dependent_expression_p (arg))
12161 args = TREE_CHAIN (args);
12166 /* Returns TRUE if the ARG (a template argument) is dependent. */
12169 dependent_template_arg_p (tree arg)
12171 if (!processing_template_decl)
12174 if (TREE_CODE (arg) == TEMPLATE_DECL
12175 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12176 return dependent_template_p (arg);
12177 else if (TYPE_P (arg))
12178 return dependent_type_p (arg);
12180 return (type_dependent_expression_p (arg)
12181 || value_dependent_expression_p (arg));
12184 /* Returns true if ARGS (a collection of template arguments) contains
12185 any dependent arguments. */
12188 any_dependent_template_arguments_p (tree args)
12196 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12198 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12199 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12200 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12207 /* Returns TRUE if the template TMPL is dependent. */
12210 dependent_template_p (tree tmpl)
12212 if (TREE_CODE (tmpl) == OVERLOAD)
12216 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12218 tmpl = OVL_CHAIN (tmpl);
12223 /* Template template parameters are dependent. */
12224 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12225 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12227 /* So are names that have not been looked up. */
12228 if (TREE_CODE (tmpl) == SCOPE_REF
12229 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12231 /* So are member templates of dependent classes. */
12232 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12233 return dependent_type_p (DECL_CONTEXT (tmpl));
12237 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12240 dependent_template_id_p (tree tmpl, tree args)
12242 return (dependent_template_p (tmpl)
12243 || any_dependent_template_arguments_p (args));
12246 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12247 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12248 can be found. Note that this function peers inside uninstantiated
12249 templates and therefore should be used only in extremely limited
12253 resolve_typename_type (tree type, bool only_current_p)
12261 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12263 scope = TYPE_CONTEXT (type);
12264 name = TYPE_IDENTIFIER (type);
12266 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12267 it first before we can figure out what NAME refers to. */
12268 if (TREE_CODE (scope) == TYPENAME_TYPE)
12269 scope = resolve_typename_type (scope, only_current_p);
12270 /* If we don't know what SCOPE refers to, then we cannot resolve the
12272 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12273 return error_mark_node;
12274 /* If the SCOPE is a template type parameter, we have no way of
12275 resolving the name. */
12276 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12278 /* If the SCOPE is not the current instantiation, there's no reason
12279 to look inside it. */
12280 if (only_current_p && !currently_open_class (scope))
12281 return error_mark_node;
12282 /* If SCOPE is a partial instantiation, it will not have a valid
12283 TYPE_FIELDS list, so use the original template. */
12284 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12285 /* Enter the SCOPE so that name lookup will be resolved as if we
12286 were in the class definition. In particular, SCOPE will no
12287 longer be considered a dependent type. */
12288 pop_p = push_scope (scope);
12289 /* Look up the declaration. */
12290 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12291 /* Obtain the set of qualifiers applied to the TYPE. */
12292 quals = cp_type_quals (type);
12293 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12294 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12296 type = error_mark_node;
12297 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12298 && TREE_CODE (decl) == TYPE_DECL)
12299 type = TREE_TYPE (decl);
12300 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12301 && DECL_CLASS_TEMPLATE_P (decl))
12305 /* Obtain the template and the arguments. */
12306 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12307 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12308 /* Instantiate the template. */
12309 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12310 /*entering_scope=*/0, tf_error | tf_user);
12313 type = error_mark_node;
12314 /* Qualify the resulting type. */
12315 if (type != error_mark_node && quals)
12316 type = cp_build_qualified_type (type, quals);
12317 /* Leave the SCOPE. */
12324 /* EXPR is an expression which is not type-dependent. Return a proxy
12325 for EXPR that can be used to compute the types of larger
12326 expressions containing EXPR. */
12329 build_non_dependent_expr (tree expr)
12333 /* Preserve null pointer constants so that the type of things like
12334 "p == 0" where "p" is a pointer can be determined. */
12335 if (null_ptr_cst_p (expr))
12337 /* Preserve OVERLOADs; the functions must be available to resolve
12339 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12340 TREE_OPERAND (expr, 0) : expr);
12341 if (TREE_CODE (inner_expr) == OVERLOAD
12342 || TREE_CODE (inner_expr) == FUNCTION_DECL
12343 || TREE_CODE (inner_expr) == TEMPLATE_DECL
12344 || TREE_CODE (inner_expr) == TEMPLATE_ID_EXPR)
12346 /* There is no need to return a proxy for a variable. */
12347 if (TREE_CODE (expr) == VAR_DECL)
12349 /* Preserve string constants; conversions from string constants to
12350 "char *" are allowed, even though normally a "const char *"
12351 cannot be used to initialize a "char *". */
12352 if (TREE_CODE (expr) == STRING_CST)
12354 /* Preserve arithmetic constants, as an optimization -- there is no
12355 reason to create a new node. */
12356 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12358 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12359 There is at least one place where we want to know that a
12360 particular expression is a throw-expression: when checking a ?:
12361 expression, there are special rules if the second or third
12362 argument is a throw-expression. */
12363 if (TREE_CODE (expr) == THROW_EXPR)
12366 if (TREE_CODE (expr) == COND_EXPR)
12367 return build3 (COND_EXPR,
12369 TREE_OPERAND (expr, 0),
12370 (TREE_OPERAND (expr, 1)
12371 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12372 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12373 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12374 if (TREE_CODE (expr) == COMPOUND_EXPR
12375 && !COMPOUND_EXPR_OVERLOADED (expr))
12376 return build2 (COMPOUND_EXPR,
12378 TREE_OPERAND (expr, 0),
12379 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12381 /* Otherwise, build a NON_DEPENDENT_EXPR.
12383 REFERENCE_TYPEs are not stripped for expressions in templates
12384 because doing so would play havoc with mangling. Consider, for
12387 template <typename T> void f<T& g>() { g(); }
12389 In the body of "f", the expression for "g" will have
12390 REFERENCE_TYPE, even though the standard says that it should
12391 not. The reason is that we must preserve the syntactic form of
12392 the expression so that mangling (say) "f<g>" inside the body of
12393 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12395 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12398 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12399 Return a new TREE_LIST with the various arguments replaced with
12400 equivalent non-dependent expressions. */
12403 build_non_dependent_args (tree args)
12408 new_args = NULL_TREE;
12409 for (a = args; a; a = TREE_CHAIN (a))
12410 new_args = tree_cons (NULL_TREE,
12411 build_non_dependent_expr (TREE_VALUE (a)),
12413 return nreverse (new_args);
12416 #include "gt-cp-pt.h"