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_decl (tree, tree, tree, tsubst_flags_t);
144 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
145 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
146 static void check_specialization_scope (void);
147 static tree process_partial_specialization (tree);
148 static void set_current_access_from_decl (tree);
149 static void check_default_tmpl_args (tree, tree, int, int);
150 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
151 static tree get_template_base (tree, tree, tree, tree);
152 static int verify_class_unification (tree, tree, tree);
153 static tree try_class_unification (tree, tree, tree, tree);
154 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
156 static tree determine_specialization (tree, tree, tree *, int, int);
157 static int template_args_equal (tree, tree);
158 static void tsubst_default_arguments (tree);
159 static tree for_each_template_parm_r (tree *, int *, void *);
160 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
161 static void copy_default_args_to_explicit_spec (tree);
162 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
163 static int eq_local_specializations (const void *, const void *);
164 static bool dependent_type_p_r (tree);
165 static tree tsubst (tree, tree, tsubst_flags_t, tree);
166 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
167 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
169 /* Make the current scope suitable for access checking when we are
170 processing T. T can be FUNCTION_DECL for instantiated function
171 template, or VAR_DECL for static member variable (need by
172 instantiate_decl). */
175 push_access_scope (tree t)
177 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
178 || TREE_CODE (t) == VAR_DECL);
180 if (DECL_CLASS_SCOPE_P (t))
181 push_nested_class (DECL_CONTEXT (t));
183 push_to_top_level ();
185 if (TREE_CODE (t) == FUNCTION_DECL)
187 saved_access_scope = tree_cons
188 (NULL_TREE, current_function_decl, saved_access_scope);
189 current_function_decl = t;
193 /* Restore the scope set up by push_access_scope. T is the node we
197 pop_access_scope (tree t)
199 if (TREE_CODE (t) == FUNCTION_DECL)
201 current_function_decl = TREE_VALUE (saved_access_scope);
202 saved_access_scope = TREE_CHAIN (saved_access_scope);
205 if (DECL_CLASS_SCOPE_P (t))
208 pop_from_top_level ();
211 /* Do any processing required when DECL (a member template
212 declaration) is finished. Returns the TEMPLATE_DECL corresponding
213 to DECL, unless it is a specialization, in which case the DECL
214 itself is returned. */
217 finish_member_template_decl (tree decl)
219 if (decl == error_mark_node)
220 return error_mark_node;
222 gcc_assert (DECL_P (decl));
224 if (TREE_CODE (decl) == TYPE_DECL)
228 type = TREE_TYPE (decl);
229 if (IS_AGGR_TYPE (type)
230 && CLASSTYPE_TEMPLATE_INFO (type)
231 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
233 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
234 check_member_template (tmpl);
239 else if (TREE_CODE (decl) == FIELD_DECL)
240 error ("data member %qD cannot be a member template", decl);
241 else if (DECL_TEMPLATE_INFO (decl))
243 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
245 check_member_template (DECL_TI_TEMPLATE (decl));
246 return DECL_TI_TEMPLATE (decl);
252 error ("invalid member template declaration %qD", decl);
254 return error_mark_node;
257 /* Returns the template nesting level of the indicated class TYPE.
267 A<T>::B<U> has depth two, while A<T> has depth one.
268 Both A<T>::B<int> and A<int>::B<U> have depth one, if
269 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
272 This function is guaranteed to return 0 if passed NULL_TREE so
273 that, for example, `template_class_depth (current_class_type)' is
277 template_class_depth_real (tree type, int count_specializations)
282 type && TREE_CODE (type) != NAMESPACE_DECL;
283 type = (TREE_CODE (type) == FUNCTION_DECL)
284 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
286 if (TREE_CODE (type) != FUNCTION_DECL)
288 if (CLASSTYPE_TEMPLATE_INFO (type)
289 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
290 && ((count_specializations
291 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
292 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
297 if (DECL_TEMPLATE_INFO (type)
298 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
299 && ((count_specializations
300 && DECL_TEMPLATE_SPECIALIZATION (type))
301 || uses_template_parms (DECL_TI_ARGS (type))))
309 /* Returns the template nesting level of the indicated class TYPE.
310 Like template_class_depth_real, but instantiations do not count in
314 template_class_depth (tree type)
316 return template_class_depth_real (type, /*count_specializations=*/0);
319 /* Returns 1 if processing DECL as part of do_pending_inlines
320 needs us to push template parms. */
323 inline_needs_template_parms (tree decl)
325 if (! DECL_TEMPLATE_INFO (decl))
328 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
329 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
332 /* Subroutine of maybe_begin_member_template_processing.
333 Push the template parms in PARMS, starting from LEVELS steps into the
334 chain, and ending at the beginning, since template parms are listed
338 push_inline_template_parms_recursive (tree parmlist, int levels)
340 tree parms = TREE_VALUE (parmlist);
344 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
346 ++processing_template_decl;
347 current_template_parms
348 = tree_cons (size_int (processing_template_decl),
349 parms, current_template_parms);
350 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
352 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
354 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
356 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
357 gcc_assert (DECL_P (parm));
359 switch (TREE_CODE (parm))
368 /* Make a CONST_DECL as is done in process_template_parm.
369 It is ugly that we recreate this here; the original
370 version built in process_template_parm is no longer
372 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
374 DECL_ARTIFICIAL (decl) = 1;
375 TREE_CONSTANT (decl) = 1;
376 TREE_INVARIANT (decl) = 1;
377 TREE_READONLY (decl) = 1;
378 DECL_INITIAL (decl) = DECL_INITIAL (parm);
379 SET_DECL_TEMPLATE_PARM_P (decl);
390 /* Restore the template parameter context for a member template or
391 a friend template defined in a class definition. */
394 maybe_begin_member_template_processing (tree decl)
399 if (inline_needs_template_parms (decl))
401 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
402 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
404 if (DECL_TEMPLATE_SPECIALIZATION (decl))
407 parms = TREE_CHAIN (parms);
410 push_inline_template_parms_recursive (parms, levels);
413 /* Remember how many levels of template parameters we pushed so that
414 we can pop them later. */
415 if (!inline_parm_levels)
416 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
417 if (inline_parm_levels_used == inline_parm_levels->num_elements)
418 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
419 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
420 ++inline_parm_levels_used;
423 /* Undo the effects of begin_member_template_processing. */
426 maybe_end_member_template_processing (void)
430 if (!inline_parm_levels_used)
433 --inline_parm_levels_used;
435 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
438 --processing_template_decl;
439 current_template_parms = TREE_CHAIN (current_template_parms);
444 /* Return a new template argument vector which contains all of ARGS,
445 but has as its innermost set of arguments the EXTRA_ARGS. */
448 add_to_template_args (tree args, tree extra_args)
455 extra_depth = TMPL_ARGS_DEPTH (extra_args);
456 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
458 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
459 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
461 for (j = 1; j <= extra_depth; ++j, ++i)
462 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
467 /* Like add_to_template_args, but only the outermost ARGS are added to
468 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
469 (EXTRA_ARGS) levels are added. This function is used to combine
470 the template arguments from a partial instantiation with the
471 template arguments used to attain the full instantiation from the
472 partial instantiation. */
475 add_outermost_template_args (tree args, tree extra_args)
479 /* If there are more levels of EXTRA_ARGS than there are ARGS,
480 something very fishy is going on. */
481 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
483 /* If *all* the new arguments will be the EXTRA_ARGS, just return
485 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
488 /* For the moment, we make ARGS look like it contains fewer levels. */
489 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
491 new_args = add_to_template_args (args, extra_args);
493 /* Now, we restore ARGS to its full dimensions. */
494 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
499 /* Return the N levels of innermost template arguments from the ARGS. */
502 get_innermost_template_args (tree args, int n)
510 /* If N is 1, just return the innermost set of template arguments. */
512 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
514 /* If we're not removing anything, just return the arguments we were
516 extra_levels = TMPL_ARGS_DEPTH (args) - n;
517 gcc_assert (extra_levels >= 0);
518 if (extra_levels == 0)
521 /* Make a new set of arguments, not containing the outer arguments. */
522 new_args = make_tree_vec (n);
523 for (i = 1; i <= n; ++i)
524 SET_TMPL_ARGS_LEVEL (new_args, i,
525 TMPL_ARGS_LEVEL (args, i + extra_levels));
530 /* We've got a template header coming up; push to a new level for storing
534 begin_template_parm_list (void)
536 /* We use a non-tag-transparent scope here, which causes pushtag to
537 put tags in this scope, rather than in the enclosing class or
538 namespace scope. This is the right thing, since we want
539 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
540 global template class, push_template_decl handles putting the
541 TEMPLATE_DECL into top-level scope. For a nested template class,
544 template <class T> struct S1 {
545 template <class T> struct S2 {};
548 pushtag contains special code to call pushdecl_with_scope on the
549 TEMPLATE_DECL for S2. */
550 begin_scope (sk_template_parms, NULL);
551 ++processing_template_decl;
552 ++processing_template_parmlist;
553 note_template_header (0);
556 /* This routine is called when a specialization is declared. If it is
557 invalid to declare a specialization here, an error is reported. */
560 check_specialization_scope (void)
562 tree scope = current_scope ();
566 An explicit specialization shall be declared in the namespace of
567 which the template is a member, or, for member templates, in the
568 namespace of which the enclosing class or enclosing class
569 template is a member. An explicit specialization of a member
570 function, member class or static data member of a class template
571 shall be declared in the namespace of which the class template
573 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
574 error ("explicit specialization in non-namespace scope %qD", scope);
578 In an explicit specialization declaration for a member of a class
579 template or a member template that appears in namespace scope,
580 the member template and some of its enclosing class templates may
581 remain unspecialized, except that the declaration shall not
582 explicitly specialize a class member template if its enclosing
583 class templates are not explicitly specialized as well. */
584 if (current_template_parms)
585 error ("enclosing class templates are not explicitly specialized");
588 /* We've just seen template <>. */
591 begin_specialization (void)
593 begin_scope (sk_template_spec, NULL);
594 note_template_header (1);
595 check_specialization_scope ();
598 /* Called at then end of processing a declaration preceded by
602 end_specialization (void)
605 reset_specialization ();
608 /* Any template <>'s that we have seen thus far are not referring to a
609 function specialization. */
612 reset_specialization (void)
614 processing_specialization = 0;
615 template_header_count = 0;
618 /* We've just seen a template header. If SPECIALIZATION is nonzero,
619 it was of the form template <>. */
622 note_template_header (int specialization)
624 processing_specialization = specialization;
625 template_header_count++;
628 /* We're beginning an explicit instantiation. */
631 begin_explicit_instantiation (void)
633 gcc_assert (!processing_explicit_instantiation);
634 processing_explicit_instantiation = true;
639 end_explicit_instantiation (void)
641 gcc_assert (processing_explicit_instantiation);
642 processing_explicit_instantiation = false;
645 /* A explicit specialization or partial specialization TMPL is being
646 declared. Check that the namespace in which the specialization is
647 occurring is permissible. Returns false iff it is invalid to
648 specialize TMPL in the current namespace. */
651 check_specialization_namespace (tree tmpl)
653 tree tpl_ns = decl_namespace_context (tmpl);
657 An explicit specialization shall be declared in the namespace of
658 which the template is a member, or, for member templates, in the
659 namespace of which the enclosing class or enclosing class
660 template is a member. An explicit specialization of a member
661 function, member class or static data member of a class template
662 shall be declared in the namespace of which the class template is
664 if (is_associated_namespace (current_namespace, tpl_ns))
665 /* Same or super-using namespace. */
669 pedwarn ("specialization of %qD in different namespace", tmpl);
670 cp_pedwarn_at (" from definition of %q#D", tmpl);
675 /* The TYPE is being declared. If it is a template type, that means it
676 is a partial specialization. Do appropriate error-checking. */
679 maybe_process_partial_specialization (tree type)
681 /* TYPE maybe an ERROR_MARK_NODE. */
682 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
684 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
686 /* This is for ordinary explicit specialization and partial
687 specialization of a template class such as:
689 template <> class C<int>;
693 template <class T> class C<T*>;
695 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
697 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
698 && !COMPLETE_TYPE_P (type))
700 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
701 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
702 if (processing_template_decl)
703 push_template_decl (TYPE_MAIN_DECL (type));
705 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
706 error ("specialization of %qT after instantiation", type);
708 else if (CLASS_TYPE_P (type)
709 && !CLASSTYPE_USE_TEMPLATE (type)
710 && CLASSTYPE_TEMPLATE_INFO (type)
711 && context && CLASS_TYPE_P (context)
712 && CLASSTYPE_TEMPLATE_INFO (context))
714 /* This is for an explicit specialization of member class
715 template according to [temp.expl.spec/18]:
717 template <> template <class U> class C<int>::D;
719 The context `C<int>' must be an implicit instantiation.
720 Otherwise this is just a member class template declared
723 template <> class C<int> { template <class U> class D; };
724 template <> template <class U> class C<int>::D;
726 In the first case, `C<int>::D' is a specialization of `C<T>::D'
727 while in the second case, `C<int>::D' is a primary template
728 and `C<T>::D' may not exist. */
730 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
731 && !COMPLETE_TYPE_P (type))
735 if (current_namespace
736 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
738 pedwarn ("specializing %q#T in different namespace", type);
739 cp_pedwarn_at (" from definition of %q#D",
740 CLASSTYPE_TI_TEMPLATE (type));
743 /* Check for invalid specialization after instantiation:
745 template <> template <> class C<int>::D<int>;
746 template <> template <class U> class C<int>::D; */
748 for (t = DECL_TEMPLATE_INSTANTIATIONS
749 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
750 t; t = TREE_CHAIN (t))
751 if (TREE_VALUE (t) != type
752 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
753 error ("specialization %qT after instantiation %qT",
754 type, TREE_VALUE (t));
756 /* Mark TYPE as a specialization. And as a result, we only
757 have one level of template argument for the innermost
759 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
760 CLASSTYPE_TI_ARGS (type)
761 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
764 else if (processing_specialization)
765 error ("explicit specialization of non-template %qT", type);
768 /* Returns nonzero if we can optimize the retrieval of specializations
769 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
770 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
773 optimize_specialization_lookup_p (tree tmpl)
775 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
776 && DECL_CLASS_SCOPE_P (tmpl)
777 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
779 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
780 /* The optimized lookup depends on the fact that the
781 template arguments for the member function template apply
782 purely to the containing class, which is not true if the
783 containing class is an explicit or partial
785 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
786 && !DECL_MEMBER_TEMPLATE_P (tmpl)
787 && !DECL_CONV_FN_P (tmpl)
788 /* It is possible to have a template that is not a member
789 template and is not a member of a template class:
791 template <typename T>
792 struct S { friend A::f(); };
794 Here, the friend function is a template, but the context does
795 not have template information. The optimized lookup relies
796 on having ARGS be the template arguments for both the class
797 and the function template. */
798 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
801 /* Retrieve the specialization (in the sense of [temp.spec] - a
802 specialization is either an instantiation or an explicit
803 specialization) of TMPL for the given template ARGS. If there is
804 no such specialization, return NULL_TREE. The ARGS are a vector of
805 arguments, or a vector of vectors of arguments, in the case of
806 templates with more than one level of parameters.
808 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
809 then we search for a partial specialization matching ARGS. This
810 parameter is ignored if TMPL is not a class template. */
813 retrieve_specialization (tree tmpl, tree args,
814 bool class_specializations_p)
816 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
818 /* There should be as many levels of arguments as there are
819 levels of parameters. */
820 gcc_assert (TMPL_ARGS_DEPTH (args)
821 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
823 if (optimize_specialization_lookup_p (tmpl))
826 tree class_specialization;
831 /* The template arguments actually apply to the containing
832 class. Find the class specialization with those
834 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
836 = retrieve_specialization (class_template, args,
837 /*class_specializations_p=*/false);
838 if (!class_specialization)
840 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
841 for the specialization. */
842 idx = class_method_index_for_fn (class_specialization, tmpl);
845 /* Iterate through the methods with the indicated name, looking
846 for the one that has an instance of TMPL. */
847 methods = CLASSTYPE_METHOD_VEC (class_specialization);
848 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
850 tree fn = OVL_CURRENT (fns);
851 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
861 /* Class templates store their instantiations on the
862 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
863 DECL_TEMPLATE_SPECIALIZATIONS list. */
864 if (!class_specializations_p
865 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
866 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
868 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
870 /* Iterate through the list until we find a matching template. */
871 while (*sp != NULL_TREE)
875 if (comp_template_args (TREE_PURPOSE (spec), args))
877 /* Use the move-to-front heuristic to speed up future
881 *sp = TREE_CHAIN (*sp);
882 TREE_CHAIN (spec) = *head;
885 return TREE_VALUE (spec);
887 sp = &TREE_CHAIN (spec);
894 /* Like retrieve_specialization, but for local declarations. */
897 retrieve_local_specialization (tree tmpl)
899 tree spec = htab_find_with_hash (local_specializations, tmpl,
900 htab_hash_pointer (tmpl));
901 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
904 /* Returns nonzero iff DECL is a specialization of TMPL. */
907 is_specialization_of (tree decl, tree tmpl)
911 if (TREE_CODE (decl) == FUNCTION_DECL)
915 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
921 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
923 for (t = TREE_TYPE (decl);
925 t = CLASSTYPE_USE_TEMPLATE (t)
926 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
927 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
934 /* Returns nonzero iff DECL is a specialization of friend declaration
935 FRIEND according to [temp.friend]. */
938 is_specialization_of_friend (tree decl, tree friend)
940 bool need_template = true;
943 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
944 || TREE_CODE (decl) == TYPE_DECL);
946 /* For [temp.friend/6] when FRIEND is an ordinary member function
947 of a template class, we want to check if DECL is a specialization
949 if (TREE_CODE (friend) == FUNCTION_DECL
950 && DECL_TEMPLATE_INFO (friend)
951 && !DECL_USE_TEMPLATE (friend))
953 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
954 friend = DECL_TI_TEMPLATE (friend);
955 need_template = false;
957 else if (TREE_CODE (friend) == TEMPLATE_DECL
958 && !PRIMARY_TEMPLATE_P (friend))
959 need_template = false;
961 /* There is nothing to do if this is not a template friend. */
962 if (TREE_CODE (friend) != TEMPLATE_DECL)
965 if (is_specialization_of (decl, friend))
969 A member of a class template may be declared to be a friend of a
970 non-template class. In this case, the corresponding member of
971 every specialization of the class template is a friend of the
972 class granting friendship.
974 For example, given a template friend declaration
976 template <class T> friend void A<T>::f();
978 the member function below is considered a friend
980 template <> struct A<int> {
984 For this type of template friend, TEMPLATE_DEPTH below will be
985 nonzero. To determine if DECL is a friend of FRIEND, we first
986 check if the enclosing class is a specialization of another. */
988 template_depth = template_class_depth (DECL_CONTEXT (friend));
990 && DECL_CLASS_SCOPE_P (decl)
991 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
992 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
994 /* Next, we check the members themselves. In order to handle
995 a few tricky cases, such as when FRIEND's are
997 template <class T> friend void A<T>::g(T t);
998 template <class T> template <T t> friend void A<T>::h();
1002 void A<int>::g(int);
1003 template <int> void A<int>::h();
1005 we need to figure out ARGS, the template arguments from
1006 the context of DECL. This is required for template substitution
1007 of `T' in the function parameter of `g' and template parameter
1008 of `h' in the above examples. Here ARGS corresponds to `int'. */
1010 tree context = DECL_CONTEXT (decl);
1011 tree args = NULL_TREE;
1012 int current_depth = 0;
1014 while (current_depth < template_depth)
1016 if (CLASSTYPE_TEMPLATE_INFO (context))
1018 if (current_depth == 0)
1019 args = TYPE_TI_ARGS (context);
1021 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1024 context = TYPE_CONTEXT (context);
1027 if (TREE_CODE (decl) == FUNCTION_DECL)
1032 tree friend_args_type;
1033 tree decl_args_type;
1035 /* Make sure that both DECL and FRIEND are templates or
1037 is_template = DECL_TEMPLATE_INFO (decl)
1038 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1039 if (need_template ^ is_template)
1041 else if (is_template)
1043 /* If both are templates, check template parameter list. */
1045 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1047 if (!comp_template_parms
1048 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1052 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1055 decl_type = TREE_TYPE (decl);
1057 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1058 tf_none, NULL_TREE);
1059 if (friend_type == error_mark_node)
1062 /* Check if return types match. */
1063 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1066 /* Check if function parameter types match, ignoring the
1067 `this' parameter. */
1068 friend_args_type = TYPE_ARG_TYPES (friend_type);
1069 decl_args_type = TYPE_ARG_TYPES (decl_type);
1070 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1071 friend_args_type = TREE_CHAIN (friend_args_type);
1072 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1073 decl_args_type = TREE_CHAIN (decl_args_type);
1075 return compparms (decl_args_type, friend_args_type);
1079 /* DECL is a TYPE_DECL */
1081 tree decl_type = TREE_TYPE (decl);
1083 /* Make sure that both DECL and FRIEND are templates or
1086 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1087 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1089 if (need_template ^ is_template)
1091 else if (is_template)
1094 /* If both are templates, check the name of the two
1095 TEMPLATE_DECL's first because is_friend didn't. */
1096 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1097 != DECL_NAME (friend))
1100 /* Now check template parameter list. */
1102 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1104 return comp_template_parms
1105 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1109 return (DECL_NAME (decl)
1110 == DECL_NAME (friend));
1116 /* Register the specialization SPEC as a specialization of TMPL with
1117 the indicated ARGS. Returns SPEC, or an equivalent prior
1118 declaration, if available. */
1121 register_specialization (tree spec, tree tmpl, tree args)
1125 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1127 if (TREE_CODE (spec) == FUNCTION_DECL
1128 && uses_template_parms (DECL_TI_ARGS (spec)))
1129 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1130 register it; we want the corresponding TEMPLATE_DECL instead.
1131 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1132 the more obvious `uses_template_parms (spec)' to avoid problems
1133 with default function arguments. In particular, given
1134 something like this:
1136 template <class T> void f(T t1, T t = T())
1138 the default argument expression is not substituted for in an
1139 instantiation unless and until it is actually needed. */
1142 /* There should be as many levels of arguments as there are
1143 levels of parameters. */
1144 gcc_assert (TMPL_ARGS_DEPTH (args)
1145 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
1147 fn = retrieve_specialization (tmpl, args,
1148 /*class_specializations_p=*/false);
1149 /* We can sometimes try to re-register a specialization that we've
1150 already got. In particular, regenerate_decl_from_template calls
1151 duplicate_decls which will update the specialization list. But,
1152 we'll still get called again here anyhow. It's more convenient
1153 to simply allow this than to try to prevent it. */
1156 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1158 if (DECL_TEMPLATE_INSTANTIATION (fn))
1161 || DECL_EXPLICIT_INSTANTIATION (fn))
1163 error ("specialization of %qD after instantiation",
1169 /* This situation should occur only if the first
1170 specialization is an implicit instantiation, the
1171 second is an explicit specialization, and the
1172 implicit instantiation has not yet been used. That
1173 situation can occur if we have implicitly
1174 instantiated a member function and then specialized
1177 We can also wind up here if a friend declaration that
1178 looked like an instantiation turns out to be a
1181 template <class T> void foo(T);
1182 class S { friend void foo<>(int) };
1183 template <> void foo(int);
1185 We transform the existing DECL in place so that any
1186 pointers to it become pointers to the updated
1189 If there was a definition for the template, but not
1190 for the specialization, we want this to look as if
1191 there were no definition, and vice versa. */
1192 DECL_INITIAL (fn) = NULL_TREE;
1193 duplicate_decls (spec, fn);
1198 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1200 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
1201 /* Dup decl failed, but this is a new definition. Set the
1202 line number so any errors match this new
1204 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1210 /* A specialization must be declared in the same namespace as the
1211 template it is specializing. */
1212 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1213 && !check_specialization_namespace (tmpl))
1214 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1216 if (!optimize_specialization_lookup_p (tmpl))
1217 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1218 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1223 /* Unregister the specialization SPEC as a specialization of TMPL.
1224 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1225 if the SPEC was listed as a specialization of TMPL. */
1228 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1232 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1234 s = &TREE_CHAIN (*s))
1235 if (TREE_VALUE (*s) == spec)
1238 *s = TREE_CHAIN (*s);
1240 TREE_VALUE (*s) = new_spec;
1247 /* Compare an entry in the local specializations hash table P1 (which
1248 is really a pointer to a TREE_LIST) with P2 (which is really a
1252 eq_local_specializations (const void *p1, const void *p2)
1254 return TREE_VALUE ((tree) p1) == (tree) p2;
1257 /* Hash P1, an entry in the local specializations table. */
1260 hash_local_specialization (const void* p1)
1262 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1265 /* Like register_specialization, but for local declarations. We are
1266 registering SPEC, an instantiation of TMPL. */
1269 register_local_specialization (tree spec, tree tmpl)
1273 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1274 htab_hash_pointer (tmpl), INSERT);
1275 *slot = build_tree_list (spec, tmpl);
1278 /* Print the list of candidate FNS in an error message. */
1281 print_candidates (tree fns)
1285 const char *str = "candidates are:";
1287 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1291 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1292 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
1297 /* Returns the template (one of the functions given by TEMPLATE_ID)
1298 which can be specialized to match the indicated DECL with the
1299 explicit template args given in TEMPLATE_ID. The DECL may be
1300 NULL_TREE if none is available. In that case, the functions in
1301 TEMPLATE_ID are non-members.
1303 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1304 specialization of a member template.
1306 The TEMPLATE_COUNT is the number of references to qualifying
1307 template classes that appeared in the name of the function. See
1308 check_explicit_specialization for a more accurate description.
1310 The template args (those explicitly specified and those deduced)
1311 are output in a newly created vector *TARGS_OUT.
1313 If it is impossible to determine the result, an error message is
1314 issued. The error_mark_node is returned to indicate failure. */
1317 determine_specialization (tree template_id,
1320 int need_member_template,
1325 tree explicit_targs;
1326 tree candidates = NULL_TREE;
1327 tree templates = NULL_TREE;
1329 struct cp_binding_level *b;
1331 *targs_out = NULL_TREE;
1333 if (template_id == error_mark_node)
1334 return error_mark_node;
1336 fns = TREE_OPERAND (template_id, 0);
1337 explicit_targs = TREE_OPERAND (template_id, 1);
1339 if (fns == error_mark_node)
1340 return error_mark_node;
1342 /* Check for baselinks. */
1343 if (BASELINK_P (fns))
1344 fns = BASELINK_FUNCTIONS (fns);
1346 if (!is_overloaded_fn (fns))
1348 error ("%qD is not a function template", fns);
1349 return error_mark_node;
1352 /* Count the number of template headers specified for this
1355 for (b = current_binding_level;
1356 b->kind == sk_template_parms || b->kind == sk_template_spec;
1360 for (; fns; fns = OVL_NEXT (fns))
1362 tree fn = OVL_CURRENT (fns);
1364 if (TREE_CODE (fn) == TEMPLATE_DECL)
1366 tree decl_arg_types;
1369 /* DECL might be a specialization of FN. */
1371 /* Adjust the type of DECL in case FN is a static member. */
1372 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1373 if (DECL_STATIC_FUNCTION_P (fn)
1374 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1375 decl_arg_types = TREE_CHAIN (decl_arg_types);
1377 /* Check that the number of function parameters matches.
1379 template <class T> void f(int i = 0);
1380 template <> void f<int>();
1381 The specialization f<int> is invalid but is not caught
1382 by get_bindings below. */
1384 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1385 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1388 /* For a non-static member function, we need to make sure that
1389 the const qualification is the same. This can be done by
1390 checking the 'this' in the argument list. */
1391 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1392 && !same_type_p (TREE_VALUE (fn_arg_types),
1393 TREE_VALUE (decl_arg_types)))
1396 /* In case of explicit specialization, we need to check if
1397 the number of template headers appearing in the specialization
1398 is correct. This is usually done in check_explicit_specialization,
1399 but the check done there cannot be exhaustive when specializing
1400 member functions. Consider the following code:
1402 template <> void A<int>::f(int);
1403 template <> template <> void A<int>::f(int);
1405 Assuming that A<int> is not itself an explicit specialization
1406 already, the first line specializes "f" which is a non-template
1407 member function, whilst the second line specializes "f" which
1408 is a template member function. So both lines are syntactically
1409 correct, and check_explicit_specialization does not reject
1412 Here, we can do better, as we are matching the specialization
1413 against the declarations. We count the number of template
1414 headers, and we check if they match TEMPLATE_COUNT + 1
1415 (TEMPLATE_COUNT is the number of qualifying template classes,
1416 plus there must be another header for the member template
1419 Notice that if header_count is zero, this is not a
1420 specialization but rather a template instantiation, so there
1421 is no check we can perform here. */
1422 if (header_count && header_count != template_count + 1)
1425 /* See whether this function might be a specialization of this
1427 targs = get_bindings (fn, decl, explicit_targs);
1430 /* We cannot deduce template arguments that when used to
1431 specialize TMPL will produce DECL. */
1434 /* Save this template, and the arguments deduced. */
1435 templates = tree_cons (targs, fn, templates);
1437 else if (need_member_template)
1438 /* FN is an ordinary member function, and we need a
1439 specialization of a member template. */
1441 else if (TREE_CODE (fn) != FUNCTION_DECL)
1442 /* We can get IDENTIFIER_NODEs here in certain erroneous
1445 else if (!DECL_FUNCTION_MEMBER_P (fn))
1446 /* This is just an ordinary non-member function. Nothing can
1447 be a specialization of that. */
1449 else if (DECL_ARTIFICIAL (fn))
1450 /* Cannot specialize functions that are created implicitly. */
1454 tree decl_arg_types;
1456 /* This is an ordinary member function. However, since
1457 we're here, we can assume it's enclosing class is a
1458 template class. For example,
1460 template <typename T> struct S { void f(); };
1461 template <> void S<int>::f() {}
1463 Here, S<int>::f is a non-template, but S<int> is a
1464 template class. If FN has the same type as DECL, we
1465 might be in business. */
1467 if (!DECL_TEMPLATE_INFO (fn))
1468 /* Its enclosing class is an explicit specialization
1469 of a template class. This is not a candidate. */
1472 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1473 TREE_TYPE (TREE_TYPE (fn))))
1474 /* The return types differ. */
1477 /* Adjust the type of DECL in case FN is a static member. */
1478 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1479 if (DECL_STATIC_FUNCTION_P (fn)
1480 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1481 decl_arg_types = TREE_CHAIN (decl_arg_types);
1483 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1486 candidates = tree_cons (NULL_TREE, fn, candidates);
1490 if (templates && TREE_CHAIN (templates))
1496 It is possible for a specialization with a given function
1497 signature to be instantiated from more than one function
1498 template. In such cases, explicit specification of the
1499 template arguments must be used to uniquely identify the
1500 function template specialization being specialized.
1502 Note that here, there's no suggestion that we're supposed to
1503 determine which of the candidate templates is most
1504 specialized. However, we, also have:
1508 Partial ordering of overloaded function template
1509 declarations is used in the following contexts to select
1510 the function template to which a function template
1511 specialization refers:
1513 -- when an explicit specialization refers to a function
1516 So, we do use the partial ordering rules, at least for now.
1517 This extension can only serve to make invalid programs valid,
1518 so it's safe. And, there is strong anecdotal evidence that
1519 the committee intended the partial ordering rules to apply;
1520 the EDG front-end has that behavior, and John Spicer claims
1521 that the committee simply forgot to delete the wording in
1522 [temp.expl.spec]. */
1523 tree tmpl = most_specialized (templates, decl, explicit_targs);
1524 if (tmpl && tmpl != error_mark_node)
1526 targs = get_bindings (tmpl, decl, explicit_targs);
1527 templates = tree_cons (targs, tmpl, NULL_TREE);
1531 if (templates == NULL_TREE && candidates == NULL_TREE)
1533 cp_error_at ("template-id %qD for %q+D does not match any template "
1536 return error_mark_node;
1538 else if ((templates && TREE_CHAIN (templates))
1539 || (candidates && TREE_CHAIN (candidates))
1540 || (templates && candidates))
1542 cp_error_at ("ambiguous template specialization %qD for %q+D",
1544 chainon (candidates, templates);
1545 print_candidates (candidates);
1546 return error_mark_node;
1549 /* We have one, and exactly one, match. */
1552 /* It was a specialization of an ordinary member function in a
1554 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1555 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1558 /* It was a specialization of a template. */
1559 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1560 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1562 *targs_out = copy_node (targs);
1563 SET_TMPL_ARGS_LEVEL (*targs_out,
1564 TMPL_ARGS_DEPTH (*targs_out),
1565 TREE_PURPOSE (templates));
1568 *targs_out = TREE_PURPOSE (templates);
1569 return TREE_VALUE (templates);
1572 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1573 but with the default argument values filled in from those in the
1577 copy_default_args_to_explicit_spec_1 (tree spec_types,
1580 tree new_spec_types;
1585 if (spec_types == void_list_node)
1586 return void_list_node;
1588 /* Substitute into the rest of the list. */
1590 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1591 TREE_CHAIN (tmpl_types));
1593 /* Add the default argument for this parameter. */
1594 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1595 TREE_VALUE (spec_types),
1599 /* DECL is an explicit specialization. Replicate default arguments
1600 from the template it specializes. (That way, code like:
1602 template <class T> void f(T = 3);
1603 template <> void f(double);
1606 works, as required.) An alternative approach would be to look up
1607 the correct default arguments at the call-site, but this approach
1608 is consistent with how implicit instantiations are handled. */
1611 copy_default_args_to_explicit_spec (tree decl)
1616 tree new_spec_types;
1620 tree object_type = NULL_TREE;
1621 tree in_charge = NULL_TREE;
1622 tree vtt = NULL_TREE;
1624 /* See if there's anything we need to do. */
1625 tmpl = DECL_TI_TEMPLATE (decl);
1626 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1627 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1628 if (TREE_PURPOSE (t))
1633 old_type = TREE_TYPE (decl);
1634 spec_types = TYPE_ARG_TYPES (old_type);
1636 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1638 /* Remove the this pointer, but remember the object's type for
1640 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1641 spec_types = TREE_CHAIN (spec_types);
1642 tmpl_types = TREE_CHAIN (tmpl_types);
1644 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1646 /* DECL may contain more parameters than TMPL due to the extra
1647 in-charge parameter in constructors and destructors. */
1648 in_charge = spec_types;
1649 spec_types = TREE_CHAIN (spec_types);
1651 if (DECL_HAS_VTT_PARM_P (decl))
1654 spec_types = TREE_CHAIN (spec_types);
1658 /* Compute the merged default arguments. */
1660 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1662 /* Compute the new FUNCTION_TYPE. */
1666 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1671 /* Put the in-charge parameter back. */
1672 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1673 TREE_VALUE (in_charge),
1676 new_type = build_method_type_directly (object_type,
1677 TREE_TYPE (old_type),
1681 new_type = build_function_type (TREE_TYPE (old_type),
1683 new_type = cp_build_type_attribute_variant (new_type,
1684 TYPE_ATTRIBUTES (old_type));
1685 new_type = build_exception_variant (new_type,
1686 TYPE_RAISES_EXCEPTIONS (old_type));
1687 TREE_TYPE (decl) = new_type;
1690 /* Check to see if the function just declared, as indicated in
1691 DECLARATOR, and in DECL, is a specialization of a function
1692 template. We may also discover that the declaration is an explicit
1693 instantiation at this point.
1695 Returns DECL, or an equivalent declaration that should be used
1696 instead if all goes well. Issues an error message if something is
1697 amiss. Returns error_mark_node if the error is not easily
1700 FLAGS is a bitmask consisting of the following flags:
1702 2: The function has a definition.
1703 4: The function is a friend.
1705 The TEMPLATE_COUNT is the number of references to qualifying
1706 template classes that appeared in the name of the function. For
1709 template <class T> struct S { void f(); };
1712 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1713 classes are not counted in the TEMPLATE_COUNT, so that in
1715 template <class T> struct S {};
1716 template <> struct S<int> { void f(); }
1717 template <> void S<int>::f();
1719 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1720 invalid; there should be no template <>.)
1722 If the function is a specialization, it is marked as such via
1723 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1724 is set up correctly, and it is added to the list of specializations
1725 for that template. */
1728 check_explicit_specialization (tree declarator,
1733 int have_def = flags & 2;
1734 int is_friend = flags & 4;
1735 int specialization = 0;
1736 int explicit_instantiation = 0;
1737 int member_specialization = 0;
1738 tree ctype = DECL_CLASS_CONTEXT (decl);
1739 tree dname = DECL_NAME (decl);
1742 tsk = current_tmpl_spec_kind (template_count);
1747 if (processing_specialization)
1750 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1752 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1755 /* This could be something like:
1757 template <class T> void f(T);
1758 class S { friend void f<>(int); } */
1762 /* This case handles bogus declarations like template <>
1763 template <class T> void f<int>(); */
1765 error ("template-id %qD in declaration of primary template",
1772 case tsk_invalid_member_spec:
1773 /* The error has already been reported in
1774 check_specialization_scope. */
1775 return error_mark_node;
1777 case tsk_invalid_expl_inst:
1778 error ("template parameter list used in explicit instantiation");
1784 error ("definition provided for explicit instantiation");
1786 explicit_instantiation = 1;
1789 case tsk_excessive_parms:
1790 case tsk_insufficient_parms:
1791 if (tsk == tsk_excessive_parms)
1792 error ("too many template parameter lists in declaration of %qD",
1794 else if (template_header_count)
1795 error("too few template parameter lists in declaration of %qD", decl);
1797 error("explicit specialization of %qD must be introduced by "
1798 "%<template <>%>", decl);
1802 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1804 member_specialization = 1;
1810 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1812 /* This case handles bogus declarations like template <>
1813 template <class T> void f<int>(); */
1815 if (uses_template_parms (declarator))
1816 error ("function template partial specialization %qD "
1817 "is not allowed", declarator);
1819 error ("template-id %qD in declaration of primary template",
1824 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1825 /* This is a specialization of a member template, without
1826 specialization the containing class. Something like:
1828 template <class T> struct S {
1829 template <class U> void f (U);
1831 template <> template <class U> void S<int>::f(U) {}
1833 That's a specialization -- but of the entire template. */
1841 if (specialization || member_specialization)
1843 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1844 for (; t; t = TREE_CHAIN (t))
1845 if (TREE_PURPOSE (t))
1848 ("default argument specified in explicit specialization");
1851 if (current_lang_name == lang_name_c)
1852 error ("template specialization with C linkage");
1855 if (specialization || member_specialization || explicit_instantiation)
1857 tree tmpl = NULL_TREE;
1858 tree targs = NULL_TREE;
1860 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1861 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1865 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1870 /* If there is no class context, the explicit instantiation
1871 must be at namespace scope. */
1872 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1874 /* Find the namespace binding, using the declaration
1876 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1879 declarator = lookup_template_function (fns, NULL_TREE);
1882 if (declarator == error_mark_node)
1883 return error_mark_node;
1885 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1887 if (!explicit_instantiation)
1888 /* A specialization in class scope. This is invalid,
1889 but the error will already have been flagged by
1890 check_specialization_scope. */
1891 return error_mark_node;
1894 /* It's not valid to write an explicit instantiation in
1897 class C { template void f(); }
1899 This case is caught by the parser. However, on
1902 template class C { void f(); };
1904 (which is invalid) we can get here. The error will be
1911 else if (ctype != NULL_TREE
1912 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1915 /* Find the list of functions in ctype that have the same
1916 name as the declared function. */
1917 tree name = TREE_OPERAND (declarator, 0);
1918 tree fns = NULL_TREE;
1921 if (constructor_name_p (name, ctype))
1923 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1925 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1926 : !TYPE_HAS_DESTRUCTOR (ctype))
1928 /* From [temp.expl.spec]:
1930 If such an explicit specialization for the member
1931 of a class template names an implicitly-declared
1932 special member function (clause _special_), the
1933 program is ill-formed.
1935 Similar language is found in [temp.explicit]. */
1936 error ("specialization of implicitly-declared special member function");
1937 return error_mark_node;
1940 name = is_constructor ? ctor_identifier : dtor_identifier;
1943 if (!DECL_CONV_FN_P (decl))
1945 idx = lookup_fnfields_1 (ctype, name);
1947 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1954 /* For a type-conversion operator, we cannot do a
1955 name-based lookup. We might be looking for `operator
1956 int' which will be a specialization of `operator T'.
1957 So, we find *all* the conversion operators, and then
1958 select from them. */
1961 methods = CLASSTYPE_METHOD_VEC (ctype);
1963 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1964 VEC_iterate (tree, methods, idx, ovl);
1967 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1968 /* There are no more conversion functions. */
1971 /* Glue all these conversion functions together
1972 with those we already have. */
1973 for (; ovl; ovl = OVL_NEXT (ovl))
1974 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1978 if (fns == NULL_TREE)
1980 error ("no member function %qD declared in %qT", name, ctype);
1981 return error_mark_node;
1984 TREE_OPERAND (declarator, 0) = fns;
1987 /* Figure out what exactly is being specialized at this point.
1988 Note that for an explicit instantiation, even one for a
1989 member function, we cannot tell apriori whether the
1990 instantiation is for a member template, or just a member
1991 function of a template class. Even if a member template is
1992 being instantiated, the member template arguments may be
1993 elided if they can be deduced from the rest of the
1995 tmpl = determine_specialization (declarator, decl,
1997 member_specialization,
2000 if (!tmpl || tmpl == error_mark_node)
2001 /* We couldn't figure out what this declaration was
2003 return error_mark_node;
2006 tree gen_tmpl = most_general_template (tmpl);
2008 if (explicit_instantiation)
2010 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2011 is done by do_decl_instantiation later. */
2013 int arg_depth = TMPL_ARGS_DEPTH (targs);
2014 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2016 if (arg_depth > parm_depth)
2018 /* If TMPL is not the most general template (for
2019 example, if TMPL is a friend template that is
2020 injected into namespace scope), then there will
2021 be too many levels of TARGS. Remove some of them
2026 new_targs = make_tree_vec (parm_depth);
2027 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2028 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2029 = TREE_VEC_ELT (targs, i);
2033 return instantiate_template (tmpl, targs, tf_error);
2036 /* If we thought that the DECL was a member function, but it
2037 turns out to be specializing a static member function,
2038 make DECL a static member function as well. */
2039 if (DECL_STATIC_FUNCTION_P (tmpl)
2040 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2041 revert_static_member_fn (decl);
2043 /* If this is a specialization of a member template of a
2044 template class. In we want to return the TEMPLATE_DECL,
2045 not the specialization of it. */
2046 if (tsk == tsk_template)
2048 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2049 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2052 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2053 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2054 = DECL_SOURCE_LOCATION (decl);
2059 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2060 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2062 /* Inherit default function arguments from the template
2063 DECL is specializing. */
2064 copy_default_args_to_explicit_spec (decl);
2066 /* This specialization has the same protection as the
2067 template it specializes. */
2068 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2069 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2071 if (is_friend && !have_def)
2072 /* This is not really a declaration of a specialization.
2073 It's just the name of an instantiation. But, it's not
2074 a request for an instantiation, either. */
2075 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2076 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2077 /* This is indeed a specialization. In case of constructors
2078 and destructors, we need in-charge and not-in-charge
2079 versions in V3 ABI. */
2080 clone_function_decl (decl, /*update_method_vec_p=*/0);
2082 /* Register this specialization so that we can find it
2084 decl = register_specialization (decl, gen_tmpl, targs);
2091 /* TYPE is being declared. Verify that the use of template headers
2092 and such is reasonable. Issue error messages if not. */
2095 maybe_check_template_type (tree type)
2097 if (template_header_count)
2099 /* We are in the scope of some `template <...>' header. */
2102 = template_class_depth_real (TYPE_CONTEXT (type),
2103 /*count_specializations=*/1);
2105 if (template_header_count <= context_depth)
2106 /* This is OK; the template headers are for the context. We
2107 are actually too lenient here; like
2108 check_explicit_specialization we should consider the number
2109 of template types included in the actual declaration. For
2112 template <class T> struct S {
2113 template <class U> template <class V>
2119 template <class T> struct S {
2120 template <class U> struct I;
2123 template <class T> template <class U.
2128 else if (template_header_count > context_depth + 1)
2129 /* There are two many template parameter lists. */
2130 error ("too many template parameter lists in declaration of %qT", type);
2134 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2135 parameters. These are represented in the same format used for
2136 DECL_TEMPLATE_PARMS. */
2139 comp_template_parms (tree parms1, tree parms2)
2144 if (parms1 == parms2)
2147 for (p1 = parms1, p2 = parms2;
2148 p1 != NULL_TREE && p2 != NULL_TREE;
2149 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2151 tree t1 = TREE_VALUE (p1);
2152 tree t2 = TREE_VALUE (p2);
2155 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2156 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2158 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2161 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2163 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2164 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2166 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2169 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2171 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2176 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2177 /* One set of parameters has more parameters lists than the
2184 /* Complain if DECL shadows a template parameter.
2186 [temp.local]: A template-parameter shall not be redeclared within its
2187 scope (including nested scopes). */
2190 check_template_shadow (tree decl)
2194 /* If we're not in a template, we can't possibly shadow a template
2196 if (!current_template_parms)
2199 /* Figure out what we're shadowing. */
2200 if (TREE_CODE (decl) == OVERLOAD)
2201 decl = OVL_CURRENT (decl);
2202 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2204 /* If there's no previous binding for this name, we're not shadowing
2205 anything, let alone a template parameter. */
2209 /* If we're not shadowing a template parameter, we're done. Note
2210 that OLDDECL might be an OVERLOAD (or perhaps even an
2211 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2213 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2216 /* We check for decl != olddecl to avoid bogus errors for using a
2217 name inside a class. We check TPFI to avoid duplicate errors for
2218 inline member templates. */
2220 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2223 cp_error_at ("declaration of %q#D", decl);
2224 cp_error_at (" shadows template parm %q#D", olddecl);
2227 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2228 ORIG_LEVEL, DECL, and TYPE. */
2231 build_template_parm_index (int index,
2237 tree t = make_node (TEMPLATE_PARM_INDEX);
2238 TEMPLATE_PARM_IDX (t) = index;
2239 TEMPLATE_PARM_LEVEL (t) = level;
2240 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2241 TEMPLATE_PARM_DECL (t) = decl;
2242 TREE_TYPE (t) = type;
2243 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2244 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2245 TREE_READONLY (t) = TREE_READONLY (decl);
2250 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2251 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2252 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2253 new one is created. */
2256 reduce_template_parm_level (tree index, tree type, int levels)
2258 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2259 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2260 != TEMPLATE_PARM_LEVEL (index) - levels))
2262 tree orig_decl = TEMPLATE_PARM_DECL (index);
2265 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2266 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2267 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2268 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2269 DECL_ARTIFICIAL (decl) = 1;
2270 SET_DECL_TEMPLATE_PARM_P (decl);
2272 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2273 TEMPLATE_PARM_LEVEL (index) - levels,
2274 TEMPLATE_PARM_ORIG_LEVEL (index),
2276 TEMPLATE_PARM_DESCENDANTS (index) = t;
2278 /* Template template parameters need this. */
2279 DECL_TEMPLATE_PARMS (decl)
2280 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2283 return TEMPLATE_PARM_DESCENDANTS (index);
2286 /* Process information from new template parameter NEXT and append it to the
2287 LIST being built. This new parameter is a non-type parameter iff
2288 IS_NON_TYPE is true. */
2291 process_template_parm (tree list, tree next, bool is_non_type)
2299 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2300 defval = TREE_PURPOSE (parm);
2304 tree p = TREE_VALUE (tree_last (list));
2306 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2307 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2309 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2317 parm = TREE_VALUE (parm);
2319 SET_DECL_TEMPLATE_PARM_P (parm);
2323 The top-level cv-qualifiers on the template-parameter are
2324 ignored when determining its type. */
2325 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2327 /* A template parameter is not modifiable. */
2328 TREE_CONSTANT (parm) = 1;
2329 TREE_INVARIANT (parm) = 1;
2330 TREE_READONLY (parm) = 1;
2331 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2332 TREE_TYPE (parm) = void_type_node;
2333 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2334 TREE_CONSTANT (decl) = 1;
2335 TREE_INVARIANT (decl) = 1;
2336 TREE_READONLY (decl) = 1;
2337 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2338 = build_template_parm_index (idx, processing_template_decl,
2339 processing_template_decl,
2340 decl, TREE_TYPE (parm));
2345 parm = TREE_VALUE (TREE_VALUE (parm));
2347 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2349 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2350 /* This is for distinguishing between real templates and template
2351 template parameters */
2352 TREE_TYPE (parm) = t;
2353 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2358 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2359 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2360 decl = build_decl (TYPE_DECL, parm, t);
2363 TYPE_NAME (t) = decl;
2364 TYPE_STUB_DECL (t) = decl;
2366 TEMPLATE_TYPE_PARM_INDEX (t)
2367 = build_template_parm_index (idx, processing_template_decl,
2368 processing_template_decl,
2369 decl, TREE_TYPE (parm));
2371 DECL_ARTIFICIAL (decl) = 1;
2372 SET_DECL_TEMPLATE_PARM_P (decl);
2374 parm = build_tree_list (defval, parm);
2375 return chainon (list, parm);
2378 /* The end of a template parameter list has been reached. Process the
2379 tree list into a parameter vector, converting each parameter into a more
2380 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2384 end_template_parm_list (tree parms)
2388 tree saved_parmlist = make_tree_vec (list_length (parms));
2390 current_template_parms
2391 = tree_cons (size_int (processing_template_decl),
2392 saved_parmlist, current_template_parms);
2394 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2396 next = TREE_CHAIN (parm);
2397 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2398 TREE_CHAIN (parm) = NULL_TREE;
2401 --processing_template_parmlist;
2403 return saved_parmlist;
2406 /* end_template_decl is called after a template declaration is seen. */
2409 end_template_decl (void)
2411 reset_specialization ();
2413 if (! processing_template_decl)
2416 /* This matches the pushlevel in begin_template_parm_list. */
2419 --processing_template_decl;
2420 current_template_parms = TREE_CHAIN (current_template_parms);
2423 /* Given a template argument vector containing the template PARMS.
2424 The innermost PARMS are given first. */
2427 current_template_args (void)
2430 tree args = NULL_TREE;
2431 int length = TMPL_PARMS_DEPTH (current_template_parms);
2434 /* If there is only one level of template parameters, we do not
2435 create a TREE_VEC of TREE_VECs. Instead, we return a single
2436 TREE_VEC containing the arguments. */
2438 args = make_tree_vec (length);
2440 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2442 tree a = copy_node (TREE_VALUE (header));
2445 TREE_TYPE (a) = NULL_TREE;
2446 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2448 tree t = TREE_VEC_ELT (a, i);
2450 /* T will be a list if we are called from within a
2451 begin/end_template_parm_list pair, but a vector directly
2452 if within a begin/end_member_template_processing pair. */
2453 if (TREE_CODE (t) == TREE_LIST)
2457 if (TREE_CODE (t) == TYPE_DECL
2458 || TREE_CODE (t) == TEMPLATE_DECL)
2461 t = DECL_INITIAL (t);
2462 TREE_VEC_ELT (a, i) = t;
2467 TREE_VEC_ELT (args, --l) = a;
2475 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2476 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2477 a member template. Used by push_template_decl below. */
2480 build_template_decl (tree decl, tree parms, bool member_template_p)
2482 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2483 DECL_TEMPLATE_PARMS (tmpl) = parms;
2484 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2485 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2486 if (DECL_LANG_SPECIFIC (decl))
2488 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2489 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2490 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2491 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2492 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2493 if (DECL_OVERLOADED_OPERATOR_P (decl))
2494 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2495 DECL_OVERLOADED_OPERATOR_P (decl));
2501 struct template_parm_data
2503 /* The level of the template parameters we are currently
2507 /* The index of the specialization argument we are currently
2511 /* An array whose size is the number of template parameters. The
2512 elements are nonzero if the parameter has been used in any one
2513 of the arguments processed so far. */
2516 /* An array whose size is the number of template arguments. The
2517 elements are nonzero if the argument makes use of template
2518 parameters of this level. */
2519 int* arg_uses_template_parms;
2522 /* Subroutine of push_template_decl used to see if each template
2523 parameter in a partial specialization is used in the explicit
2524 argument list. If T is of the LEVEL given in DATA (which is
2525 treated as a template_parm_data*), then DATA->PARMS is marked
2529 mark_template_parm (tree t, void* data)
2533 struct template_parm_data* tpd = (struct template_parm_data*) data;
2535 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2537 level = TEMPLATE_PARM_LEVEL (t);
2538 idx = TEMPLATE_PARM_IDX (t);
2542 level = TEMPLATE_TYPE_LEVEL (t);
2543 idx = TEMPLATE_TYPE_IDX (t);
2546 if (level == tpd->level)
2548 tpd->parms[idx] = 1;
2549 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2552 /* Return zero so that for_each_template_parm will continue the
2553 traversal of the tree; we want to mark *every* template parm. */
2557 /* Process the partial specialization DECL. */
2560 process_partial_specialization (tree decl)
2562 tree type = TREE_TYPE (decl);
2563 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2564 tree specargs = CLASSTYPE_TI_ARGS (type);
2565 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2566 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2567 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2568 int nargs = TREE_VEC_LENGTH (inner_args);
2569 int ntparms = TREE_VEC_LENGTH (inner_parms);
2571 int did_error_intro = 0;
2572 struct template_parm_data tpd;
2573 struct template_parm_data tpd2;
2575 /* We check that each of the template parameters given in the
2576 partial specialization is used in the argument list to the
2577 specialization. For example:
2579 template <class T> struct S;
2580 template <class T> struct S<T*>;
2582 The second declaration is OK because `T*' uses the template
2583 parameter T, whereas
2585 template <class T> struct S<int>;
2587 is no good. Even trickier is:
2598 The S2<T> declaration is actually invalid; it is a
2599 full-specialization. Of course,
2602 struct S2<T (*)(U)>;
2604 or some such would have been OK. */
2605 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2606 tpd.parms = alloca (sizeof (int) * ntparms);
2607 memset (tpd.parms, 0, sizeof (int) * ntparms);
2609 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2610 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2611 for (i = 0; i < nargs; ++i)
2613 tpd.current_arg = i;
2614 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2615 &mark_template_parm,
2619 for (i = 0; i < ntparms; ++i)
2620 if (tpd.parms[i] == 0)
2622 /* One of the template parms was not used in the
2624 if (!did_error_intro)
2626 error ("template parameters not used in partial specialization:");
2627 did_error_intro = 1;
2630 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2633 /* [temp.class.spec]
2635 The argument list of the specialization shall not be identical to
2636 the implicit argument list of the primary template. */
2637 if (comp_template_args
2639 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2641 error ("partial specialization %qT does not specialize any template arguments", type);
2643 /* [temp.class.spec]
2645 A partially specialized non-type argument expression shall not
2646 involve template parameters of the partial specialization except
2647 when the argument expression is a simple identifier.
2649 The type of a template parameter corresponding to a specialized
2650 non-type argument shall not be dependent on a parameter of the
2652 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2654 for (i = 0; i < nargs; ++i)
2656 tree arg = TREE_VEC_ELT (inner_args, i);
2657 if (/* These first two lines are the `non-type' bit. */
2659 && TREE_CODE (arg) != TEMPLATE_DECL
2660 /* This next line is the `argument expression is not just a
2661 simple identifier' condition and also the `specialized
2662 non-type argument' bit. */
2663 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2665 if (tpd.arg_uses_template_parms[i])
2666 error ("template argument %qE involves template parameter(s)", arg);
2669 /* Look at the corresponding template parameter,
2670 marking which template parameters its type depends
2673 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2678 /* We haven't yet initialized TPD2. Do so now. */
2679 tpd2.arg_uses_template_parms
2680 = alloca (sizeof (int) * nargs);
2681 /* The number of parameters here is the number in the
2682 main template, which, as checked in the assertion
2684 tpd2.parms = alloca (sizeof (int) * nargs);
2686 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2689 /* Mark the template parameters. But this time, we're
2690 looking for the template parameters of the main
2691 template, not in the specialization. */
2692 tpd2.current_arg = i;
2693 tpd2.arg_uses_template_parms[i] = 0;
2694 memset (tpd2.parms, 0, sizeof (int) * nargs);
2695 for_each_template_parm (type,
2696 &mark_template_parm,
2700 if (tpd2.arg_uses_template_parms [i])
2702 /* The type depended on some template parameters.
2703 If they are fully specialized in the
2704 specialization, that's OK. */
2706 for (j = 0; j < nargs; ++j)
2707 if (tpd2.parms[j] != 0
2708 && tpd.arg_uses_template_parms [j])
2710 error ("type %qT of template argument %qE depends "
2711 "on template parameter(s)",
2721 if (retrieve_specialization (maintmpl, specargs,
2722 /*class_specializations_p=*/true))
2723 /* We've already got this specialization. */
2726 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2727 = tree_cons (inner_args, inner_parms,
2728 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2729 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2733 /* Check that a template declaration's use of default arguments is not
2734 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2735 nonzero if DECL is the thing declared by a primary template.
2736 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2739 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2742 int last_level_to_check;
2747 A default template-argument shall not be specified in a
2748 function template declaration or a function template definition, nor
2749 in the template-parameter-list of the definition of a member of a
2752 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2753 /* You can't have a function template declaration in a local
2754 scope, nor you can you define a member of a class template in a
2758 if (current_class_type
2759 && !TYPE_BEING_DEFINED (current_class_type)
2760 && DECL_LANG_SPECIFIC (decl)
2761 /* If this is either a friend defined in the scope of the class
2762 or a member function. */
2763 && (DECL_FUNCTION_MEMBER_P (decl)
2764 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2765 : DECL_FRIEND_CONTEXT (decl)
2766 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2768 /* And, if it was a member function, it really was defined in
2769 the scope of the class. */
2770 && (!DECL_FUNCTION_MEMBER_P (decl)
2771 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2772 /* We already checked these parameters when the template was
2773 declared, so there's no need to do it again now. This function
2774 was defined in class scope, but we're processing it's body now
2775 that the class is complete. */
2780 If a template-parameter has a default template-argument, all
2781 subsequent template-parameters shall have a default
2782 template-argument supplied. */
2783 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2785 tree inner_parms = TREE_VALUE (parm_level);
2786 int ntparms = TREE_VEC_LENGTH (inner_parms);
2787 int seen_def_arg_p = 0;
2790 for (i = 0; i < ntparms; ++i)
2792 tree parm = TREE_VEC_ELT (inner_parms, i);
2793 if (TREE_PURPOSE (parm))
2795 else if (seen_def_arg_p)
2797 error ("no default argument for %qD", TREE_VALUE (parm));
2798 /* For better subsequent error-recovery, we indicate that
2799 there should have been a default argument. */
2800 TREE_PURPOSE (parm) = error_mark_node;
2805 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2806 /* For an ordinary class template, default template arguments are
2807 allowed at the innermost level, e.g.:
2808 template <class T = int>
2810 but, in a partial specialization, they're not allowed even
2811 there, as we have in [temp.class.spec]:
2813 The template parameter list of a specialization shall not
2814 contain default template argument values.
2816 So, for a partial specialization, or for a function template,
2817 we look at all of them. */
2820 /* But, for a primary class template that is not a partial
2821 specialization we look at all template parameters except the
2823 parms = TREE_CHAIN (parms);
2825 /* Figure out what error message to issue. */
2826 if (TREE_CODE (decl) == FUNCTION_DECL)
2827 msg = "default template arguments may not be used in function templates";
2828 else if (is_partial)
2829 msg = "default template arguments may not be used in partial specializations";
2831 msg = "default argument for template parameter for class enclosing %qD";
2833 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2834 /* If we're inside a class definition, there's no need to
2835 examine the parameters to the class itself. On the one
2836 hand, they will be checked when the class is defined, and,
2837 on the other, default arguments are valid in things like:
2838 template <class T = double>
2839 struct S { template <class U> void f(U); };
2840 Here the default argument for `S' has no bearing on the
2841 declaration of `f'. */
2842 last_level_to_check = template_class_depth (current_class_type) + 1;
2844 /* Check everything. */
2845 last_level_to_check = 0;
2847 for (parm_level = parms;
2848 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2849 parm_level = TREE_CHAIN (parm_level))
2851 tree inner_parms = TREE_VALUE (parm_level);
2855 ntparms = TREE_VEC_LENGTH (inner_parms);
2856 for (i = 0; i < ntparms; ++i)
2857 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2865 /* Clear out the default argument so that we are not
2867 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2870 /* At this point, if we're still interested in issuing messages,
2871 they must apply to classes surrounding the object declared. */
2873 msg = "default argument for template parameter for class enclosing %qD";
2877 /* Worker for push_template_decl_real, called via
2878 for_each_template_parm. DATA is really an int, indicating the
2879 level of the parameters we are interested in. If T is a template
2880 parameter of that level, return nonzero. */
2883 template_parm_this_level_p (tree t, void* data)
2885 int this_level = *(int *)data;
2888 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2889 level = TEMPLATE_PARM_LEVEL (t);
2891 level = TEMPLATE_TYPE_LEVEL (t);
2892 return level == this_level;
2895 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2896 parameters given by current_template_args, or reuses a
2897 previously existing one, if appropriate. Returns the DECL, or an
2898 equivalent one, if it is replaced via a call to duplicate_decls.
2900 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2903 push_template_decl_real (tree decl, int is_friend)
2911 int new_template_p = 0;
2912 /* True if the template is a member template, in the sense of
2914 bool member_template_p = false;
2916 if (decl == error_mark_node)
2919 /* See if this is a partial specialization. */
2920 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2921 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2922 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2924 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2927 /* For a friend, we want the context of the friend function, not
2928 the type of which it is a friend. */
2929 ctx = DECL_CONTEXT (decl);
2930 else if (CP_DECL_CONTEXT (decl)
2931 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2932 /* In the case of a virtual function, we want the class in which
2934 ctx = CP_DECL_CONTEXT (decl);
2936 /* Otherwise, if we're currently defining some class, the DECL
2937 is assumed to be a member of the class. */
2938 ctx = current_scope ();
2940 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2943 if (!DECL_CONTEXT (decl))
2944 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2946 /* See if this is a primary template. */
2947 primary = template_parm_scope_p ();
2951 if (DECL_CLASS_SCOPE_P (decl))
2952 member_template_p = true;
2953 if (current_lang_name == lang_name_c)
2954 error ("template with C linkage");
2955 else if (TREE_CODE (decl) == TYPE_DECL
2956 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2957 error ("template class without a name");
2958 else if (TREE_CODE (decl) == FUNCTION_DECL)
2960 if (DECL_DESTRUCTOR_P (decl))
2964 A destructor shall not be a member template. */
2965 error ("destructor %qD declared as member template", decl);
2966 return error_mark_node;
2968 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2969 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2970 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2971 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2972 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2973 == void_list_node)))
2975 /* [basic.stc.dynamic.allocation]
2977 An allocation function can be a function
2978 template. ... Template allocation functions shall
2979 have two or more parameters. */
2980 error ("invalid template declaration of %qD", decl);
2984 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2985 && CLASS_TYPE_P (TREE_TYPE (decl)))
2986 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx)))
2990 error ("template declaration of %q#D", decl);
2991 return error_mark_node;
2995 /* Check to see that the rules regarding the use of default
2996 arguments are not being violated. */
2997 check_default_tmpl_args (decl, current_template_parms,
2998 primary, is_partial);
3001 return process_partial_specialization (decl);
3003 args = current_template_args ();
3006 || TREE_CODE (ctx) == FUNCTION_DECL
3007 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3008 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3010 if (DECL_LANG_SPECIFIC (decl)
3011 && DECL_TEMPLATE_INFO (decl)
3012 && DECL_TI_TEMPLATE (decl))
3013 tmpl = DECL_TI_TEMPLATE (decl);
3014 /* If DECL is a TYPE_DECL for a class-template, then there won't
3015 be DECL_LANG_SPECIFIC. The information equivalent to
3016 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3017 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3018 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3019 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3021 /* Since a template declaration already existed for this
3022 class-type, we must be redeclaring it here. Make sure
3023 that the redeclaration is valid. */
3024 redeclare_class_template (TREE_TYPE (decl),
3025 current_template_parms);
3026 /* We don't need to create a new TEMPLATE_DECL; just use the
3027 one we already had. */
3028 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3032 tmpl = build_template_decl (decl, current_template_parms,
3036 if (DECL_LANG_SPECIFIC (decl)
3037 && DECL_TEMPLATE_SPECIALIZATION (decl))
3039 /* A specialization of a member template of a template
3041 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3042 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3043 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3049 tree a, t, current, parms;
3052 if (TREE_CODE (decl) == TYPE_DECL)
3054 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3055 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3056 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3057 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3058 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3061 error ("%qD does not declare a template type", decl);
3065 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3067 error ("template definition of non-template %q#D", decl);
3071 tmpl = DECL_TI_TEMPLATE (decl);
3073 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3074 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3075 && DECL_TEMPLATE_SPECIALIZATION (decl)
3076 && DECL_MEMBER_TEMPLATE_P (tmpl))
3080 /* The declaration is a specialization of a member
3081 template, declared outside the class. Therefore, the
3082 innermost template arguments will be NULL, so we
3083 replace them with the arguments determined by the
3084 earlier call to check_explicit_specialization. */
3085 args = DECL_TI_ARGS (decl);
3088 = build_template_decl (decl, current_template_parms,
3090 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3091 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3092 DECL_TI_TEMPLATE (decl) = new_tmpl;
3093 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3094 DECL_TEMPLATE_INFO (new_tmpl)
3095 = tree_cons (tmpl, args, NULL_TREE);
3097 register_specialization (new_tmpl,
3098 most_general_template (tmpl),
3103 /* Make sure the template headers we got make sense. */
3105 parms = DECL_TEMPLATE_PARMS (tmpl);
3106 i = TMPL_PARMS_DEPTH (parms);
3107 if (TMPL_ARGS_DEPTH (args) != i)
3109 error ("expected %d levels of template parms for %q#D, got %d",
3110 i, decl, TMPL_ARGS_DEPTH (args));
3113 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3115 a = TMPL_ARGS_LEVEL (args, i);
3116 t = INNERMOST_TEMPLATE_PARMS (parms);
3118 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3120 if (current == decl)
3121 error ("got %d template parameters for %q#D",
3122 TREE_VEC_LENGTH (a), decl);
3124 error ("got %d template parameters for %q#T",
3125 TREE_VEC_LENGTH (a), current);
3126 error (" but %d required", TREE_VEC_LENGTH (t));
3129 /* Perhaps we should also check that the parms are used in the
3130 appropriate qualifying scopes in the declarator? */
3132 if (current == decl)
3135 current = TYPE_CONTEXT (current);
3139 DECL_TEMPLATE_RESULT (tmpl) = decl;
3140 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3142 /* Push template declarations for global functions and types. Note
3143 that we do not try to push a global template friend declared in a
3144 template class; such a thing may well depend on the template
3145 parameters of the class. */
3146 if (new_template_p && !ctx
3147 && !(is_friend && template_class_depth (current_class_type) > 0))
3148 tmpl = pushdecl_namespace_level (tmpl);
3152 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3153 if (DECL_CONV_FN_P (tmpl))
3155 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3157 /* It is a conversion operator. See if the type converted to
3158 depends on innermost template operands. */
3160 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3162 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3166 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3167 back to its most general template. If TMPL is a specialization,
3168 ARGS may only have the innermost set of arguments. Add the missing
3169 argument levels if necessary. */
3170 if (DECL_TEMPLATE_INFO (tmpl))
3171 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3173 info = tree_cons (tmpl, args, NULL_TREE);
3175 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3177 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3178 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3179 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3180 /* Don't change the name if we've already set it up. */
3181 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3182 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3184 else if (DECL_LANG_SPECIFIC (decl))
3185 DECL_TEMPLATE_INFO (decl) = info;
3187 return DECL_TEMPLATE_RESULT (tmpl);
3191 push_template_decl (tree decl)
3193 return push_template_decl_real (decl, 0);
3196 /* Called when a class template TYPE is redeclared with the indicated
3197 template PARMS, e.g.:
3199 template <class T> struct S;
3200 template <class T> struct S {}; */
3203 redeclare_class_template (tree type, tree parms)
3209 if (!TYPE_TEMPLATE_INFO (type))
3211 error ("%qT is not a template type", type);
3215 tmpl = TYPE_TI_TEMPLATE (type);
3216 if (!PRIMARY_TEMPLATE_P (tmpl))
3217 /* The type is nested in some template class. Nothing to worry
3218 about here; there are no new template parameters for the nested
3222 parms = INNERMOST_TEMPLATE_PARMS (parms);
3223 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3225 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3227 cp_error_at ("previous declaration %qD", tmpl);
3228 error ("used %d template parameter%s instead of %d",
3229 TREE_VEC_LENGTH (tmpl_parms),
3230 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
3231 TREE_VEC_LENGTH (parms));
3235 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3237 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3238 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3239 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3240 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3242 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3244 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3245 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3246 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3248 cp_error_at ("template parameter %q#D", tmpl_parm);
3249 error ("redeclared here as %q#D", parm);
3253 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3255 /* We have in [temp.param]:
3257 A template-parameter may not be given default arguments
3258 by two different declarations in the same scope. */
3259 error ("redefinition of default argument for %q#D", parm);
3260 error ("%J original definition appeared here", tmpl_parm);
3264 if (parm_default != NULL_TREE)
3265 /* Update the previous template parameters (which are the ones
3266 that will really count) with the new default value. */
3267 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3268 else if (tmpl_default != NULL_TREE)
3269 /* Update the new parameters, too; they'll be used as the
3270 parameters for any members. */
3271 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3275 /* Simplify EXPR if it is a non-dependent expression. Returns the
3276 (possibly simplified) expression. */
3279 fold_non_dependent_expr (tree expr)
3281 /* If we're in a template, but EXPR isn't value dependent, simplify
3282 it. We're supposed to treat:
3284 template <typename T> void f(T[1 + 1]);
3285 template <typename T> void f(T[2]);
3287 as two declarations of the same function, for example. */
3288 if (processing_template_decl
3289 && !type_dependent_expression_p (expr)
3290 && !value_dependent_expression_p (expr))
3292 HOST_WIDE_INT saved_processing_template_decl;
3294 saved_processing_template_decl = processing_template_decl;
3295 processing_template_decl = 0;
3296 expr = tsubst_copy_and_build (expr,
3299 /*in_decl=*/NULL_TREE,
3300 /*function_p=*/false);
3301 processing_template_decl = saved_processing_template_decl;
3306 /* EXPR is an expression which is used in a constant-expression context.
3307 For instance, it could be a VAR_DECL with a constant initializer.
3308 Extract the innest constant expression.
3310 This is basically a more powerful version of decl_constant_value, which
3311 can be used also in templates where initializers can maintain a
3312 syntactic rather than semantic form (even if they are non-dependent, for
3313 access-checking purposes). */
3316 fold_decl_constant_value (tree expr)
3320 tree const_expr = decl_constant_value (expr);
3321 /* In a template, the initializer for a VAR_DECL may not be
3322 marked as TREE_CONSTANT, in which case decl_constant_value
3323 will not return the initializer. Handle that special case
3325 if (expr == const_expr
3326 && TREE_CODE (expr) == VAR_DECL
3327 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (expr)
3328 && CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (expr))
3329 /* DECL_INITIAL can be NULL if we are processing a
3330 variable initialized to an expression involving itself.
3331 We know it is initialized to a constant -- but not what
3333 && DECL_INITIAL (expr))
3334 const_expr = DECL_INITIAL (expr);
3335 if (expr == const_expr)
3337 expr = fold_non_dependent_expr (const_expr);
3343 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3344 must be a function or a pointer-to-function type, as specified
3345 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3346 and check that the resulting function has external linkage. */
3349 convert_nontype_argument_function (tree type, tree expr)
3354 fn = instantiate_type (type, fns, tf_none);
3355 if (fn == error_mark_node)
3356 return error_mark_node;
3359 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3360 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3362 /* [temp.arg.nontype]/1
3364 A template-argument for a non-type, non-template template-parameter
3367 -- the address of an object or function with external linkage. */
3368 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3370 error ("%qE is not a valid template argument for type %qT "
3371 "because function %qD has not external linkage",
3372 expr, type, fn_no_ptr);
3379 /* Attempt to convert the non-type template parameter EXPR to the
3380 indicated TYPE. If the conversion is successful, return the
3381 converted value. If the conversion is unsuccessful, return
3382 NULL_TREE if we issued an error message, or error_mark_node if we
3383 did not. We issue error messages for out-and-out bad template
3384 parameters, but not simply because the conversion failed, since we
3385 might be just trying to do argument deduction. Both TYPE and EXPR
3386 must be non-dependent.
3388 The conversion follows the special rules described in
3389 [temp.arg.nontype], and it is much more strict than an implicit
3392 This function is called twice for each template argument (see
3393 lookup_template_class for a more accurate description of this
3394 problem). This means that we need to handle expressions which
3395 are not valid in a C++ source, but can be created from the
3396 first call (for instance, casts to perform conversions). These
3397 hacks can go away after we fix the double coercion problem. */
3400 convert_nontype_argument (tree type, tree expr)
3404 /* Detect immediately string literals as invalid non-type argument.
3405 This special-case is not needed for correctness (we would easily
3406 catch this later), but only to provide better diagnostic for this
3407 common user mistake. As suggested by DR 100, we do not mention
3408 linkage issues in the diagnostic as this is not the point. */
3409 if (TREE_CODE (expr) == STRING_CST)
3411 error ("%qE is not a valid template argument for type %qT "
3412 "because string literals can never be used in this context",
3417 /* If we are in a template, EXPR may be non-dependent, but still
3418 have a syntactic, rather than semantic, form. For example, EXPR
3419 might be a SCOPE_REF, rather than the VAR_DECL to which the
3420 SCOPE_REF refers. Preserving the qualifying scope is necessary
3421 so that access checking can be performed when the template is
3422 instantiated -- but here we need the resolved form so that we can
3423 convert the argument. */
3424 expr = fold_non_dependent_expr (expr);
3425 expr_type = TREE_TYPE (expr);
3427 /* HACK: Due to double coercion, we can get a
3428 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3429 which is the tree that we built on the first call (see
3430 below when coercing to reference to object or to reference to
3431 function). We just strip everything and get to the arg.
3432 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3434 if (TREE_CODE (expr) == NOP_EXPR)
3436 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3438 /* ??? Maybe we could use convert_from_reference here, but we
3439 would need to relax its constraints because the NOP_EXPR
3440 could actually change the type to something more cv-qualified,
3441 and this is not folded by convert_from_reference. */
3442 tree addr = TREE_OPERAND (expr, 0);
3443 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3444 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3445 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3446 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3447 (TREE_TYPE (expr_type),
3448 TREE_TYPE (TREE_TYPE (addr))));
3450 expr = TREE_OPERAND (addr, 0);
3451 expr_type = TREE_TYPE (expr);
3454 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3455 parameter is a pointer to object, through decay and
3456 qualification conversion. Let's strip everything. */
3457 else if (TYPE_PTROBV_P (type))
3460 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3461 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3462 /* Skip the ADDR_EXPR only if it is part of the decay for
3463 an array. Otherwise, it is part of the original argument
3464 in the source code. */
3465 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3466 expr = TREE_OPERAND (expr, 0);
3467 expr_type = TREE_TYPE (expr);
3471 /* [temp.arg.nontype]/5, bullet 1
3473 For a non-type template-parameter of integral or enumeration type,
3474 integral promotions (_conv.prom_) and integral conversions
3475 (_conv.integral_) are applied. */
3476 if (INTEGRAL_TYPE_P (type))
3478 if (!INTEGRAL_TYPE_P (expr_type))
3479 return error_mark_node;
3481 expr = fold_decl_constant_value (expr);
3482 /* Notice that there are constant expressions like '4 % 0' which
3483 do not fold into integer constants. */
3484 if (TREE_CODE (expr) != INTEGER_CST)
3486 error ("%qE is not a valid template argument for type %qT "
3487 "because it is a non-constant expression", expr, type);
3491 /* At this point, an implicit conversion does what we want,
3492 because we already know that the expression is of integral
3494 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3495 if (expr == error_mark_node)
3496 return error_mark_node;
3498 /* Conversion was allowed: fold it to a bare integer constant. */
3501 /* [temp.arg.nontype]/5, bullet 2
3503 For a non-type template-parameter of type pointer to object,
3504 qualification conversions (_conv.qual_) and the array-to-pointer
3505 conversion (_conv.array_) are applied. */
3506 else if (TYPE_PTROBV_P (type))
3508 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3510 A template-argument for a non-type, non-template template-parameter
3511 shall be one of: [...]
3513 -- the name of a non-type template-parameter;
3514 -- the address of an object or function with external linkage, [...]
3515 expressed as "& id-expression" where the & is optional if the name
3516 refers to a function or array, or if the corresponding
3517 template-parameter is a reference.
3519 Here, we do not care about functions, as they are invalid anyway
3520 for a parameter of type pointer-to-object. */
3521 bool constant_address_p =
3522 (TREE_CODE (expr) == ADDR_EXPR
3523 || TREE_CODE (expr_type) == ARRAY_TYPE
3524 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3526 expr = decay_conversion (expr);
3527 if (expr == error_mark_node)
3528 return error_mark_node;
3530 expr = perform_qualification_conversions (type, expr);
3531 if (expr == error_mark_node)
3532 return error_mark_node;
3534 if (!constant_address_p)
3536 error ("%qE is not a valid template argument for type %qT "
3537 "because it is not a constant pointer", expr, type);
3541 /* [temp.arg.nontype]/5, bullet 3
3543 For a non-type template-parameter of type reference to object, no
3544 conversions apply. The type referred to by the reference may be more
3545 cv-qualified than the (otherwise identical) type of the
3546 template-argument. The template-parameter is bound directly to the
3547 template-argument, which must be an lvalue. */
3548 else if (TYPE_REF_OBJ_P (type))
3550 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3552 return error_mark_node;
3554 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3556 error ("%qE is not a valid template argument for type %qT "
3557 "because of conflicts in cv-qualification", expr, type);
3561 if (!real_lvalue_p (expr))
3563 error ("%qE is not a valid template argument for type %qT "
3564 "because it is not a lvalue", expr, type);
3568 /* [temp.arg.nontype]/1
3570 A template-argument for a non-type, non-template template-parameter
3571 shall be one of: [...]
3573 -- the address of an object or function with external linkage. */
3574 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3576 error ("%qE is not a valid template argument for type %qT "
3577 "because object %qD has not external linkage",
3582 expr = build_nop (type, build_address (expr));
3584 /* [temp.arg.nontype]/5, bullet 4
3586 For a non-type template-parameter of type pointer to function, only
3587 the function-to-pointer conversion (_conv.func_) is applied. If the
3588 template-argument represents a set of overloaded functions (or a
3589 pointer to such), the matching function is selected from the set
3591 else if (TYPE_PTRFN_P (type))
3593 /* If the argument is a template-id, we might not have enough
3594 context information to decay the pointer.
3595 ??? Why static5.C requires decay and subst1.C works fine
3597 if (!type_unknown_p (expr_type))
3599 expr = decay_conversion (expr);
3600 if (expr == error_mark_node)
3601 return error_mark_node;
3604 expr = convert_nontype_argument_function (type, expr);
3605 if (!expr || expr == error_mark_node)
3608 /* [temp.arg.nontype]/5, bullet 5
3610 For a non-type template-parameter of type reference to function, no
3611 conversions apply. If the template-argument represents a set of
3612 overloaded functions, the matching function is selected from the set
3614 else if (TYPE_REFFN_P (type))
3616 if (TREE_CODE (expr) == ADDR_EXPR)
3618 error ("%qE is not a valid template argument for type %qT "
3619 "because it is a pointer", expr, type);
3620 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3624 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3625 if (!expr || expr == error_mark_node)
3628 expr = build_nop(type, build_address (expr));
3630 /* [temp.arg.nontype]/5, bullet 6
3632 For a non-type template-parameter of type pointer to member function,
3633 no conversions apply. If the template-argument represents a set of
3634 overloaded member functions, the matching member function is selected
3635 from the set (_over.over_). */
3636 else if (TYPE_PTRMEMFUNC_P (type))
3638 expr = instantiate_type (type, expr, tf_none);
3639 if (expr == error_mark_node)
3640 return error_mark_node;
3642 /* There is no way to disable standard conversions in
3643 resolve_address_of_overloaded_function (called by
3644 instantiate_type). It is possible that the call succeeded by
3645 converting &B::I to &D::I (where B is a base of D), so we need
3646 to reject this conversion here.
3648 Actually, even if there was a way to disable standard conversions,
3649 it would still be better to reject them here so that we can
3650 provide a superior diagnostic. */
3651 if (!same_type_p (TREE_TYPE (expr), type))
3653 /* Make sure we are just one standard conversion off. */
3654 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3655 error ("%qE is not a valid template argument for type %qT "
3656 "because it is of type %qT", expr, type,
3658 inform ("standard conversions are not allowed in this context");
3662 /* [temp.arg.nontype]/5, bullet 7
3664 For a non-type template-parameter of type pointer to data member,
3665 qualification conversions (_conv.qual_) are applied. */
3666 else if (TYPE_PTRMEM_P (type))
3668 expr = perform_qualification_conversions (type, expr);
3669 if (expr == error_mark_node)
3672 /* A template non-type parameter must be one of the above. */
3676 /* Sanity check: did we actually convert the argument to the
3678 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3683 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3684 template template parameters. Both PARM_PARMS and ARG_PARMS are
3685 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3688 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3689 the case, then extra parameters must have default arguments.
3691 Consider the example:
3692 template <class T, class Allocator = allocator> class vector;
3693 template<template <class U> class TT> class C;
3695 C<vector> is a valid instantiation. PARM_PARMS for the above code
3696 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3697 T and Allocator) and OUTER_ARGS contains the argument that is used to
3698 substitute the TT parameter. */
3701 coerce_template_template_parms (tree parm_parms,
3703 tsubst_flags_t complain,
3707 int nparms, nargs, i;
3710 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3711 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3713 nparms = TREE_VEC_LENGTH (parm_parms);
3714 nargs = TREE_VEC_LENGTH (arg_parms);
3716 /* The rule here is opposite of coerce_template_parms. */
3719 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3722 for (i = 0; i < nparms; ++i)
3724 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3725 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3727 if (arg == NULL_TREE || arg == error_mark_node
3728 || parm == NULL_TREE || parm == error_mark_node)
3731 if (TREE_CODE (arg) != TREE_CODE (parm))
3734 switch (TREE_CODE (parm))
3740 /* We encounter instantiations of templates like
3741 template <template <template <class> class> class TT>
3744 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3745 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3747 if (!coerce_template_template_parms
3748 (parmparm, argparm, complain, in_decl, outer_args))
3754 /* The tsubst call is used to handle cases such as
3756 template <int> class C {};
3757 template <class T, template <T> class TT> class D {};
3760 i.e. the parameter list of TT depends on earlier parameters. */
3761 if (!dependent_type_p (TREE_TYPE (arg))
3763 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3775 /* Convert the indicated template ARG as necessary to match the
3776 indicated template PARM. Returns the converted ARG, or
3777 error_mark_node if the conversion was unsuccessful. Error and
3778 warning messages are issued under control of COMPLAIN. This
3779 conversion is for the Ith parameter in the parameter list. ARGS is
3780 the full set of template arguments deduced so far. */
3783 convert_template_argument (tree parm,
3786 tsubst_flags_t complain,
3792 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3794 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3796 if (TREE_CODE (arg) == TREE_LIST
3797 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3799 /* The template argument was the name of some
3800 member function. That's usually
3801 invalid, but static members are OK. In any
3802 case, grab the underlying fields/functions
3803 and issue an error later if required. */
3804 arg = TREE_VALUE (arg);
3805 TREE_TYPE (arg) = unknown_type_node;
3808 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3809 requires_type = (TREE_CODE (parm) == TYPE_DECL
3810 || requires_tmpl_type);
3812 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3813 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3814 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3815 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3818 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3819 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3820 arg = TYPE_STUB_DECL (arg);
3822 is_type = TYPE_P (arg) || is_tmpl_type;
3824 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3825 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3827 pedwarn ("to refer to a type member of a template parameter, "
3828 "use %<typename %E%>", arg);
3830 arg = make_typename_type (TREE_OPERAND (arg, 0),
3831 TREE_OPERAND (arg, 1),
3832 complain & tf_error);
3835 if (is_type != requires_type)
3839 if (complain & tf_error)
3841 error ("type/value mismatch at argument %d in template "
3842 "parameter list for %qD",
3845 error (" expected a constant of type %qT, got %qT",
3847 (is_tmpl_type ? DECL_NAME (arg) : arg));
3848 else if (requires_tmpl_type)
3849 error (" expected a class template, got %qE", arg);
3851 error (" expected a type, got %qE", arg);
3854 return error_mark_node;
3856 if (is_tmpl_type ^ requires_tmpl_type)
3858 if (in_decl && (complain & tf_error))
3860 error ("type/value mismatch at argument %d in template "
3861 "parameter list for %qD",
3864 error (" expected a type, got %qT", DECL_NAME (arg));
3866 error (" expected a class template, got %qT", arg);
3868 return error_mark_node;
3873 if (requires_tmpl_type)
3875 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3876 /* The number of argument required is not known yet.
3877 Just accept it for now. */
3878 val = TREE_TYPE (arg);
3881 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3882 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3884 if (coerce_template_template_parms (parmparm, argparm,
3890 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3892 if (val != error_mark_node
3893 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3894 val = TREE_TYPE (val);
3898 if (in_decl && (complain & tf_error))
3900 error ("type/value mismatch at argument %d in "
3901 "template parameter list for %qD",
3903 error (" expected a template of type %qD, got %qD",
3907 val = error_mark_node;
3916 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3918 if (invalid_nontype_parm_type_p (t, complain))
3919 return error_mark_node;
3921 if (!uses_template_parms (arg) && !uses_template_parms (t))
3922 /* We used to call digest_init here. However, digest_init
3923 will report errors, which we don't want when complain
3924 is zero. More importantly, digest_init will try too
3925 hard to convert things: for example, `0' should not be
3926 converted to pointer type at this point according to
3927 the standard. Accepting this is not merely an
3928 extension, since deciding whether or not these
3929 conversions can occur is part of determining which
3930 function template to call, or whether a given explicit
3931 argument specification is valid. */
3932 val = convert_nontype_argument (t, arg);
3936 if (val == NULL_TREE)
3937 val = error_mark_node;
3938 else if (val == error_mark_node && (complain & tf_error))
3939 error ("could not convert template argument %qE to %qT", arg, t);
3945 /* Convert all template arguments to their appropriate types, and
3946 return a vector containing the innermost resulting template
3947 arguments. If any error occurs, return error_mark_node. Error and
3948 warning messages are issued under control of COMPLAIN.
3950 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3951 provided in ARGLIST, or else trailing parameters must have default
3952 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3953 deduction for any unspecified trailing arguments. */
3956 coerce_template_parms (tree parms,
3959 tsubst_flags_t complain,
3960 int require_all_arguments)
3962 int nparms, nargs, i, lost = 0;
3965 tree new_inner_args;
3967 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3968 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3969 nparms = TREE_VEC_LENGTH (parms);
3973 && require_all_arguments
3974 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3976 if (complain & tf_error)
3978 error ("wrong number of template arguments (%d, should be %d)",
3982 cp_error_at ("provided for %qD", in_decl);
3985 return error_mark_node;
3988 new_inner_args = make_tree_vec (nparms);
3989 new_args = add_outermost_template_args (args, new_inner_args);
3990 for (i = 0; i < nparms; i++)
3995 /* Get the Ith template parameter. */
3996 parm = TREE_VEC_ELT (parms, i);
3998 /* Calculate the Ith argument. */
4000 arg = TREE_VEC_ELT (inner_args, i);
4001 else if (require_all_arguments)
4002 /* There must be a default arg in this case. */
4003 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4009 if (arg == error_mark_node)
4011 if (complain & tf_error)
4012 error ("template argument %d is invalid", i + 1);
4015 arg = convert_template_argument (TREE_VALUE (parm),
4016 arg, new_args, complain, i,
4019 if (arg == error_mark_node)
4021 TREE_VEC_ELT (new_inner_args, i) = arg;
4025 return error_mark_node;
4027 return new_inner_args;
4030 /* Returns 1 if template args OT and NT are equivalent. */
4033 template_args_equal (tree ot, tree nt)
4038 if (TREE_CODE (nt) == TREE_VEC)
4039 /* For member templates */
4040 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4041 else if (TYPE_P (nt))
4042 return TYPE_P (ot) && same_type_p (ot, nt);
4043 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4046 return cp_tree_equal (ot, nt);
4049 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4050 of template arguments. Returns 0 otherwise. */
4053 comp_template_args (tree oldargs, tree newargs)
4057 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4060 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4062 tree nt = TREE_VEC_ELT (newargs, i);
4063 tree ot = TREE_VEC_ELT (oldargs, i);
4065 if (! template_args_equal (ot, nt))
4071 /* Given class template name and parameter list, produce a user-friendly name
4072 for the instantiation. */
4075 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4077 static struct obstack scratch_obstack;
4078 static char *scratch_firstobj;
4081 if (!scratch_firstobj)
4082 gcc_obstack_init (&scratch_obstack);
4084 obstack_free (&scratch_obstack, scratch_firstobj);
4085 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4087 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4088 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4092 nparms = TREE_VEC_LENGTH (parms);
4093 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4094 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4095 for (i = 0; i < nparms; i++)
4097 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4098 tree arg = TREE_VEC_ELT (arglist, i);
4103 if (TREE_CODE (parm) == TYPE_DECL)
4105 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4108 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4110 if (TREE_CODE (arg) == TEMPLATE_DECL)
4112 /* Already substituted with real template. Just output
4113 the template name here */
4114 tree context = DECL_CONTEXT (arg);
4117 /* The template may be defined in a namespace, or
4118 may be a member template. */
4119 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4120 || CLASS_TYPE_P (context));
4121 cat (decl_as_string (DECL_CONTEXT (arg),
4122 TFF_PLAIN_IDENTIFIER));
4125 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4128 /* Output the parameter declaration. */
4129 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4133 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4135 /* No need to check arglist against parmlist here; we did that
4136 in coerce_template_parms, called from lookup_template_class. */
4137 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4140 char *bufp = obstack_next_free (&scratch_obstack);
4142 while (bufp[offset - 1] == ' ')
4144 obstack_blank_fast (&scratch_obstack, offset);
4146 /* B<C<char> >, not B<C<char>> */
4147 if (bufp[offset - 1] == '>')
4152 return (char *) obstack_base (&scratch_obstack);
4156 classtype_mangled_name (tree t)
4158 if (CLASSTYPE_TEMPLATE_INFO (t)
4159 /* Specializations have already had their names set up in
4160 lookup_template_class. */
4161 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4163 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4165 /* For non-primary templates, the template parameters are
4166 implicit from their surrounding context. */
4167 if (PRIMARY_TEMPLATE_P (tmpl))
4169 tree name = DECL_NAME (tmpl);
4170 char *mangled_name = mangle_class_name_for_template
4171 (IDENTIFIER_POINTER (name),
4172 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4173 CLASSTYPE_TI_ARGS (t));
4174 tree id = get_identifier (mangled_name);
4175 IDENTIFIER_TEMPLATE (id) = name;
4180 return TYPE_IDENTIFIER (t);
4184 add_pending_template (tree d)
4186 tree ti = (TYPE_P (d)
4187 ? CLASSTYPE_TEMPLATE_INFO (d)
4188 : DECL_TEMPLATE_INFO (d));
4192 if (TI_PENDING_TEMPLATE_FLAG (ti))
4195 /* We are called both from instantiate_decl, where we've already had a
4196 tinst_level pushed, and instantiate_template, where we haven't.
4198 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4201 push_tinst_level (d);
4203 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4204 if (last_pending_template)
4205 TREE_CHAIN (last_pending_template) = pt;
4207 pending_templates = pt;
4209 last_pending_template = pt;
4211 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4218 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4219 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4220 documentation for TEMPLATE_ID_EXPR. */
4223 lookup_template_function (tree fns, tree arglist)
4227 if (fns == error_mark_node || arglist == error_mark_node)
4228 return error_mark_node;
4230 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4231 if (fns == NULL_TREE
4232 || TREE_CODE (fns) == FUNCTION_DECL)
4234 error ("non-template used as template");
4235 return error_mark_node;
4238 gcc_assert (TREE_CODE (fns) == TEMPLATE_DECL
4239 || TREE_CODE (fns) == OVERLOAD
4241 || TREE_CODE (fns) == IDENTIFIER_NODE);
4243 if (BASELINK_P (fns))
4245 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4247 BASELINK_FUNCTIONS (fns),
4252 type = TREE_TYPE (fns);
4253 if (TREE_CODE (fns) == OVERLOAD || !type)
4254 type = unknown_type_node;
4256 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4259 /* Within the scope of a template class S<T>, the name S gets bound
4260 (in build_self_reference) to a TYPE_DECL for the class, not a
4261 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4262 or one of its enclosing classes, and that type is a template,
4263 return the associated TEMPLATE_DECL. Otherwise, the original
4264 DECL is returned. */
4267 maybe_get_template_decl_from_type_decl (tree decl)
4269 return (decl != NULL_TREE
4270 && TREE_CODE (decl) == TYPE_DECL
4271 && DECL_ARTIFICIAL (decl)
4272 && CLASS_TYPE_P (TREE_TYPE (decl))
4273 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4274 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4277 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4278 parameters, find the desired type.
4280 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4282 IN_DECL, if non-NULL, is the template declaration we are trying to
4285 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4286 the class we are looking up.
4288 Issue error and warning messages under control of COMPLAIN.
4290 If the template class is really a local class in a template
4291 function, then the FUNCTION_CONTEXT is the function in which it is
4294 ??? Note that this function is currently called *twice* for each
4295 template-id: the first time from the parser, while creating the
4296 incomplete type (finish_template_type), and the second type during the
4297 real instantiation (instantiate_template_class). This is surely something
4298 that we want to avoid. It also causes some problems with argument
4299 coercion (see convert_nontype_argument for more information on this). */
4302 lookup_template_class (tree d1,
4307 tsubst_flags_t complain)
4309 tree template = NULL_TREE, parmlist;
4312 timevar_push (TV_NAME_LOOKUP);
4314 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4316 tree value = innermost_non_namespace_value (d1);
4317 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4322 push_decl_namespace (context);
4323 template = lookup_name (d1, /*prefer_type=*/0);
4324 template = maybe_get_template_decl_from_type_decl (template);
4326 pop_decl_namespace ();
4329 context = DECL_CONTEXT (template);
4331 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4333 tree type = TREE_TYPE (d1);
4335 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4336 an implicit typename for the second A. Deal with it. */
4337 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4338 type = TREE_TYPE (type);
4340 if (CLASSTYPE_TEMPLATE_INFO (type))
4342 template = CLASSTYPE_TI_TEMPLATE (type);
4343 d1 = DECL_NAME (template);
4346 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4347 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4349 template = TYPE_TI_TEMPLATE (d1);
4350 d1 = DECL_NAME (template);
4352 else if (TREE_CODE (d1) == TEMPLATE_DECL
4353 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4356 d1 = DECL_NAME (template);
4357 context = DECL_CONTEXT (template);
4360 /* Issue an error message if we didn't find a template. */
4363 if (complain & tf_error)
4364 error ("%qT is not a template", d1);
4365 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4368 if (TREE_CODE (template) != TEMPLATE_DECL
4369 /* Make sure it's a user visible template, if it was named by
4371 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4372 && !PRIMARY_TEMPLATE_P (template)))
4374 if (complain & tf_error)
4376 error ("non-template type %qT used as a template", d1);
4378 cp_error_at ("for template declaration %qD", in_decl);
4380 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4383 complain &= ~tf_user;
4385 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4387 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4388 template arguments */
4393 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4395 /* Consider an example where a template template parameter declared as
4397 template <class T, class U = std::allocator<T> > class TT
4399 The template parameter level of T and U are one level larger than
4400 of TT. To proper process the default argument of U, say when an
4401 instantiation `TT<int>' is seen, we need to build the full
4402 arguments containing {int} as the innermost level. Outer levels,
4403 available when not appearing as default template argument, can be
4404 obtained from `current_template_args ()'.
4406 Suppose that TT is later substituted with std::vector. The above
4407 instantiation is `TT<int, std::allocator<T> >' with TT at
4408 level 1, and T at level 2, while the template arguments at level 1
4409 becomes {std::vector} and the inner level 2 is {int}. */
4411 if (current_template_parms)
4412 arglist = add_to_template_args (current_template_args (), arglist);
4414 arglist2 = coerce_template_parms (parmlist, arglist, template,
4415 complain, /*require_all_args=*/1);
4416 if (arglist2 == error_mark_node
4417 || (!uses_template_parms (arglist2)
4418 && check_instantiated_args (template, arglist2, complain)))
4419 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4421 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4422 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4426 tree template_type = TREE_TYPE (template);
4429 tree found = NULL_TREE;
4432 int is_partial_instantiation;
4434 gen_tmpl = most_general_template (template);
4435 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4436 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4437 arg_depth = TMPL_ARGS_DEPTH (arglist);
4439 if (arg_depth == 1 && parm_depth > 1)
4441 /* We've been given an incomplete set of template arguments.
4444 template <class T> struct S1 {
4445 template <class U> struct S2 {};
4446 template <class U> struct S2<U*> {};
4449 we will be called with an ARGLIST of `U*', but the
4450 TEMPLATE will be `template <class T> template
4451 <class U> struct S1<T>::S2'. We must fill in the missing
4454 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4456 arg_depth = TMPL_ARGS_DEPTH (arglist);
4459 /* Now we should have enough arguments. */
4460 gcc_assert (parm_depth == arg_depth);
4462 /* From here on, we're only interested in the most general
4464 template = gen_tmpl;
4466 /* Calculate the BOUND_ARGS. These will be the args that are
4467 actually tsubst'd into the definition to create the
4471 /* We have multiple levels of arguments to coerce, at once. */
4473 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4475 tree bound_args = make_tree_vec (parm_depth);
4477 for (i = saved_depth,
4478 t = DECL_TEMPLATE_PARMS (template);
4479 i > 0 && t != NULL_TREE;
4480 --i, t = TREE_CHAIN (t))
4482 tree a = coerce_template_parms (TREE_VALUE (t),
4484 complain, /*require_all_args=*/1);
4486 /* Don't process further if one of the levels fails. */
4487 if (a == error_mark_node)
4489 /* Restore the ARGLIST to its full size. */
4490 TREE_VEC_LENGTH (arglist) = saved_depth;
4491 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4494 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4496 /* We temporarily reduce the length of the ARGLIST so
4497 that coerce_template_parms will see only the arguments
4498 corresponding to the template parameters it is
4500 TREE_VEC_LENGTH (arglist)--;
4503 /* Restore the ARGLIST to its full size. */
4504 TREE_VEC_LENGTH (arglist) = saved_depth;
4506 arglist = bound_args;
4510 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4511 INNERMOST_TEMPLATE_ARGS (arglist),
4513 complain, /*require_all_args=*/1);
4515 if (arglist == error_mark_node)
4516 /* We were unable to bind the arguments. */
4517 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4519 /* In the scope of a template class, explicit references to the
4520 template class refer to the type of the template, not any
4521 instantiation of it. For example, in:
4523 template <class T> class C { void f(C<T>); }
4525 the `C<T>' is just the same as `C'. Outside of the
4526 class, however, such a reference is an instantiation. */
4527 if (comp_template_args (TYPE_TI_ARGS (template_type),
4530 found = template_type;
4532 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4536 for (ctx = current_class_type;
4537 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4539 ? TYPE_CONTEXT (ctx)
4540 : DECL_CONTEXT (ctx)))
4541 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4544 /* We're not in the scope of the class, so the
4545 TEMPLATE_TYPE is not the type we want after all. */
4551 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4553 /* If we already have this specialization, return it. */
4554 found = retrieve_specialization (template, arglist,
4555 /*class_specializations_p=*/false);
4557 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4559 /* This type is a "partial instantiation" if any of the template
4560 arguments still involve template parameters. Note that we set
4561 IS_PARTIAL_INSTANTIATION for partial specializations as
4563 is_partial_instantiation = uses_template_parms (arglist);
4565 /* If the deduced arguments are invalid, then the binding
4567 if (!is_partial_instantiation
4568 && check_instantiated_args (template,
4569 INNERMOST_TEMPLATE_ARGS (arglist),
4571 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4573 if (!is_partial_instantiation
4574 && !PRIMARY_TEMPLATE_P (template)
4575 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4577 found = xref_tag_from_type (TREE_TYPE (template),
4578 DECL_NAME (template),
4580 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4583 context = tsubst (DECL_CONTEXT (template), arglist,
4586 context = global_namespace;
4588 /* Create the type. */
4589 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4591 if (!is_partial_instantiation)
4593 set_current_access_from_decl (TYPE_NAME (template_type));
4594 t = start_enum (TYPE_IDENTIFIER (template_type));
4597 /* We don't want to call start_enum for this type, since
4598 the values for the enumeration constants may involve
4599 template parameters. And, no one should be interested
4600 in the enumeration constants for such a type. */
4601 t = make_node (ENUMERAL_TYPE);
4605 t = make_aggr_type (TREE_CODE (template_type));
4606 CLASSTYPE_DECLARED_CLASS (t)
4607 = CLASSTYPE_DECLARED_CLASS (template_type);
4608 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4609 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4611 /* A local class. Make sure the decl gets registered properly. */
4612 if (context == current_function_decl)
4613 pushtag (DECL_NAME (template), t, 0);
4616 /* If we called start_enum or pushtag above, this information
4617 will already be set up. */
4620 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4622 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4623 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4624 TYPE_STUB_DECL (t) = type_decl;
4625 DECL_SOURCE_LOCATION (type_decl)
4626 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4629 type_decl = TYPE_NAME (t);
4631 TREE_PRIVATE (type_decl)
4632 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4633 TREE_PROTECTED (type_decl)
4634 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4636 /* Set up the template information. We have to figure out which
4637 template is the immediate parent if this is a full
4639 if (parm_depth == 1 || is_partial_instantiation
4640 || !PRIMARY_TEMPLATE_P (template))
4641 /* This case is easy; there are no member templates involved. */
4645 /* This is a full instantiation of a member template. Look
4646 for a partial instantiation of which this is an instance. */
4648 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4649 found; found = TREE_CHAIN (found))
4652 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4654 /* We only want partial instantiations, here, not
4655 specializations or full instantiations. */
4656 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4657 || !uses_template_parms (TREE_VALUE (found)))
4660 /* Temporarily reduce by one the number of levels in the
4661 ARGLIST and in FOUND so as to avoid comparing the
4662 last set of arguments. */
4663 TREE_VEC_LENGTH (arglist)--;
4664 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4666 /* See if the arguments match. If they do, then TMPL is
4667 the partial instantiation we want. */
4668 success = comp_template_args (TREE_PURPOSE (found), arglist);
4670 /* Restore the argument vectors to their full size. */
4671 TREE_VEC_LENGTH (arglist)++;
4672 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4683 /* There was no partial instantiation. This happens
4684 where C<T> is a member template of A<T> and it's used
4687 template <typename T> struct B { A<T>::C<int> m; };
4690 Create the partial instantiation.
4692 TREE_VEC_LENGTH (arglist)--;
4693 found = tsubst (template, arglist, complain, NULL_TREE);
4694 TREE_VEC_LENGTH (arglist)++;
4698 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4699 DECL_TEMPLATE_INSTANTIATIONS (template)
4700 = tree_cons (arglist, t,
4701 DECL_TEMPLATE_INSTANTIATIONS (template));
4703 if (TREE_CODE (t) == ENUMERAL_TYPE
4704 && !is_partial_instantiation)
4705 /* Now that the type has been registered on the instantiations
4706 list, we set up the enumerators. Because the enumeration
4707 constants may involve the enumeration type itself, we make
4708 sure to register the type first, and then create the
4709 constants. That way, doing tsubst_expr for the enumeration
4710 constants won't result in recursive calls here; we'll find
4711 the instantiation and exit above. */
4712 tsubst_enum (template_type, t, arglist);
4714 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4716 if (TREE_CODE (t) != ENUMERAL_TYPE)
4717 DECL_NAME (type_decl) = classtype_mangled_name (t);
4718 if (is_partial_instantiation)
4719 /* If the type makes use of template parameters, the
4720 code that generates debugging information will crash. */
4721 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4723 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4725 timevar_pop (TV_NAME_LOOKUP);
4732 struct pointer_set_t *visited;
4735 /* Called from for_each_template_parm via walk_tree. */
4738 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4741 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4742 tree_fn_t fn = pfd->fn;
4743 void *data = pfd->data;
4746 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4747 return error_mark_node;
4749 switch (TREE_CODE (t))
4752 if (TYPE_PTRMEMFUNC_P (t))
4758 if (!TYPE_TEMPLATE_INFO (t))
4760 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4761 fn, data, pfd->visited))
4762 return error_mark_node;
4766 /* Since we're not going to walk subtrees, we have to do this
4768 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4770 return error_mark_node;
4774 /* Check the return type. */
4775 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4776 return error_mark_node;
4778 /* Check the parameter types. Since default arguments are not
4779 instantiated until they are needed, the TYPE_ARG_TYPES may
4780 contain expressions that involve template parameters. But,
4781 no-one should be looking at them yet. And, once they're
4782 instantiated, they don't contain template parameters, so
4783 there's no point in looking at them then, either. */
4787 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4788 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4790 return error_mark_node;
4792 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4793 want walk_tree walking into them itself. */
4799 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4801 return error_mark_node;
4806 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4807 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4809 return error_mark_node;
4814 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4815 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4817 return error_mark_node;
4818 if (DECL_CONTEXT (t)
4819 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4821 return error_mark_node;
4824 case BOUND_TEMPLATE_TEMPLATE_PARM:
4825 /* Record template parameters such as `T' inside `TT<T>'. */
4826 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4827 return error_mark_node;
4830 case TEMPLATE_TEMPLATE_PARM:
4831 case TEMPLATE_TYPE_PARM:
4832 case TEMPLATE_PARM_INDEX:
4833 if (fn && (*fn)(t, data))
4834 return error_mark_node;
4836 return error_mark_node;
4840 /* A template template parameter is encountered. */
4841 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4842 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4843 return error_mark_node;
4845 /* Already substituted template template parameter */
4851 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4852 data, pfd->visited))
4853 return error_mark_node;
4857 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4858 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4859 (TREE_TYPE (t)), fn, data,
4861 return error_mark_node;
4866 /* If there's no type, then this thing must be some expression
4867 involving template parameters. */
4868 if (!fn && !TREE_TYPE (t))
4869 return error_mark_node;
4874 case REINTERPRET_CAST_EXPR:
4875 case CONST_CAST_EXPR:
4876 case STATIC_CAST_EXPR:
4877 case DYNAMIC_CAST_EXPR:
4881 case PSEUDO_DTOR_EXPR:
4883 return error_mark_node;
4887 /* If we do not handle this case specially, we end up walking
4888 the BINFO hierarchy, which is circular, and therefore
4889 confuses walk_tree. */
4891 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4893 return error_mark_node;
4900 /* We didn't find any template parameters we liked. */
4904 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4905 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4906 call FN with the parameter and the DATA.
4907 If FN returns nonzero, the iteration is terminated, and
4908 for_each_template_parm returns 1. Otherwise, the iteration
4909 continues. If FN never returns a nonzero value, the value
4910 returned by for_each_template_parm is 0. If FN is NULL, it is
4911 considered to be the function which always returns 1. */
4914 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4915 struct pointer_set_t *visited)
4917 struct pair_fn_data pfd;
4924 /* Walk the tree. (Conceptually, we would like to walk without
4925 duplicates, but for_each_template_parm_r recursively calls
4926 for_each_template_parm, so we would need to reorganize a fair
4927 bit to use walk_tree_without_duplicates, so we keep our own
4930 pfd.visited = visited;
4932 pfd.visited = pointer_set_create ();
4933 result = walk_tree (&t,
4934 for_each_template_parm_r,
4936 pfd.visited) != NULL_TREE;
4941 pointer_set_destroy (pfd.visited);
4948 /* Returns true if T depends on any template parameter. */
4951 uses_template_parms (tree t)
4954 int saved_processing_template_decl;
4956 saved_processing_template_decl = processing_template_decl;
4957 if (!saved_processing_template_decl)
4958 processing_template_decl = 1;
4960 dependent_p = dependent_type_p (t);
4961 else if (TREE_CODE (t) == TREE_VEC)
4962 dependent_p = any_dependent_template_arguments_p (t);
4963 else if (TREE_CODE (t) == TREE_LIST)
4964 dependent_p = (uses_template_parms (TREE_VALUE (t))
4965 || uses_template_parms (TREE_CHAIN (t)));
4968 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4969 || TREE_CODE (t) == OVERLOAD
4970 || TREE_CODE (t) == BASELINK
4971 || CONSTANT_CLASS_P (t))
4972 dependent_p = (type_dependent_expression_p (t)
4973 || value_dependent_expression_p (t));
4976 gcc_assert (t == error_mark_node);
4977 dependent_p = false;
4980 processing_template_decl = saved_processing_template_decl;
4985 /* Returns true if T depends on any template parameter with level LEVEL. */
4988 uses_template_parms_level (tree t, int level)
4990 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4993 static int tinst_depth;
4994 extern int max_tinst_depth;
4995 #ifdef GATHER_STATISTICS
4998 static int tinst_level_tick;
4999 static int last_template_error_tick;
5001 /* We're starting to instantiate D; record the template instantiation context
5002 for diagnostics and to restore it later. */
5005 push_tinst_level (tree d)
5009 if (tinst_depth >= max_tinst_depth)
5011 /* If the instantiation in question still has unbound template parms,
5012 we don't really care if we can't instantiate it, so just return.
5013 This happens with base instantiation for implicit `typename'. */
5014 if (uses_template_parms (d))
5017 last_template_error_tick = tinst_level_tick;
5018 error ("template instantiation depth exceeds maximum of %d (use "
5019 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5020 max_tinst_depth, d);
5022 print_instantiation_context ();
5027 new = make_tinst_level (d, input_location);
5028 TREE_CHAIN (new) = current_tinst_level;
5029 current_tinst_level = new;
5032 #ifdef GATHER_STATISTICS
5033 if (tinst_depth > depth_reached)
5034 depth_reached = tinst_depth;
5041 /* We're done instantiating this template; return to the instantiation
5045 pop_tinst_level (void)
5047 tree old = current_tinst_level;
5049 /* Restore the filename and line number stashed away when we started
5050 this instantiation. */
5051 input_location = TINST_LOCATION (old);
5052 current_tinst_level = TREE_CHAIN (old);
5057 /* We're instantiating a deferred template; restore the template
5058 instantiation context in which the instantiation was requested, which
5059 is one step out from LEVEL. */
5062 reopen_tinst_level (tree level)
5067 for (t = level; t; t = TREE_CHAIN (t))
5070 current_tinst_level = level;
5074 /* Return the outermost template instantiation context, for use with
5075 -falt-external-templates. */
5078 tinst_for_decl (void)
5080 tree p = current_tinst_level;
5083 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
5088 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5089 vector of template arguments, as for tsubst.
5091 Returns an appropriate tsubst'd friend declaration. */
5094 tsubst_friend_function (tree decl, tree args)
5097 location_t saved_loc = input_location;
5099 input_location = DECL_SOURCE_LOCATION (decl);
5101 if (TREE_CODE (decl) == FUNCTION_DECL
5102 && DECL_TEMPLATE_INSTANTIATION (decl)
5103 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5104 /* This was a friend declared with an explicit template
5105 argument list, e.g.:
5109 to indicate that f was a template instantiation, not a new
5110 function declaration. Now, we have to figure out what
5111 instantiation of what template. */
5113 tree template_id, arglist, fns;
5116 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5118 /* Friend functions are looked up in the containing namespace scope.
5119 We must enter that scope, to avoid finding member functions of the
5120 current cless with same name. */
5121 push_nested_namespace (ns);
5122 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5123 tf_error | tf_warning, NULL_TREE);
5124 pop_nested_namespace (ns);
5125 arglist = tsubst (DECL_TI_ARGS (decl), args,
5126 tf_error | tf_warning, NULL_TREE);
5127 template_id = lookup_template_function (fns, arglist);
5129 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5130 tmpl = determine_specialization (template_id, new_friend,
5132 /*need_member_template=*/0,
5133 TREE_VEC_LENGTH (args));
5134 new_friend = instantiate_template (tmpl, new_args, tf_error);
5138 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5140 /* The NEW_FRIEND will look like an instantiation, to the
5141 compiler, but is not an instantiation from the point of view of
5142 the language. For example, we might have had:
5144 template <class T> struct S {
5145 template <class U> friend void f(T, U);
5148 Then, in S<int>, template <class U> void f(int, U) is not an
5149 instantiation of anything. */
5150 if (new_friend == error_mark_node)
5151 return error_mark_node;
5153 DECL_USE_TEMPLATE (new_friend) = 0;
5154 if (TREE_CODE (decl) == TEMPLATE_DECL)
5156 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5157 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5158 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5161 /* The mangled name for the NEW_FRIEND is incorrect. The function
5162 is not a template instantiation and should not be mangled like
5163 one. Therefore, we forget the mangling here; we'll recompute it
5164 later if we need it. */
5165 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5167 SET_DECL_RTL (new_friend, NULL_RTX);
5168 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5171 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5174 tree new_friend_template_info;
5175 tree new_friend_result_template_info;
5177 int new_friend_is_defn;
5179 /* We must save some information from NEW_FRIEND before calling
5180 duplicate decls since that function will free NEW_FRIEND if
5182 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5183 new_friend_is_defn =
5184 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5185 (template_for_substitution (new_friend)))
5187 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5189 /* This declaration is a `primary' template. */
5190 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5192 new_friend_result_template_info
5193 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5196 new_friend_result_template_info = NULL_TREE;
5198 /* Inside pushdecl_namespace_level, we will push into the
5199 current namespace. However, the friend function should go
5200 into the namespace of the template. */
5201 ns = decl_namespace_context (new_friend);
5202 push_nested_namespace (ns);
5203 old_decl = pushdecl_namespace_level (new_friend);
5204 pop_nested_namespace (ns);
5206 if (old_decl != new_friend)
5208 /* This new friend declaration matched an existing
5209 declaration. For example, given:
5211 template <class T> void f(T);
5212 template <class U> class C {
5213 template <class T> friend void f(T) {}
5216 the friend declaration actually provides the definition
5217 of `f', once C has been instantiated for some type. So,
5218 old_decl will be the out-of-class template declaration,
5219 while new_friend is the in-class definition.
5221 But, if `f' was called before this point, the
5222 instantiation of `f' will have DECL_TI_ARGS corresponding
5223 to `T' but not to `U', references to which might appear
5224 in the definition of `f'. Previously, the most general
5225 template for an instantiation of `f' was the out-of-class
5226 version; now it is the in-class version. Therefore, we
5227 run through all specialization of `f', adding to their
5228 DECL_TI_ARGS appropriately. In particular, they need a
5229 new set of outer arguments, corresponding to the
5230 arguments for this class instantiation.
5232 The same situation can arise with something like this:
5235 template <class T> class C {
5239 when `C<int>' is instantiated. Now, `f(int)' is defined
5242 if (!new_friend_is_defn)
5243 /* On the other hand, if the in-class declaration does
5244 *not* provide a definition, then we don't want to alter
5245 existing definitions. We can just leave everything
5250 /* Overwrite whatever template info was there before, if
5251 any, with the new template information pertaining to
5253 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5255 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5256 reregister_specialization (new_friend,
5257 most_general_template (old_decl),
5262 tree new_friend_args;
5264 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5265 = new_friend_result_template_info;
5267 new_friend_args = TI_ARGS (new_friend_template_info);
5268 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5272 tree spec = TREE_VALUE (t);
5275 = add_outermost_template_args (new_friend_args,
5276 DECL_TI_ARGS (spec));
5279 /* Now, since specializations are always supposed to
5280 hang off of the most general template, we must move
5282 t = most_general_template (old_decl);
5285 DECL_TEMPLATE_SPECIALIZATIONS (t)
5286 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5287 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5288 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5293 /* The information from NEW_FRIEND has been merged into OLD_DECL
5294 by duplicate_decls. */
5295 new_friend = old_decl;
5298 else if (COMPLETE_TYPE_P (DECL_CONTEXT (new_friend)))
5300 /* Check to see that the declaration is really present, and,
5301 possibly obtain an improved declaration. */
5302 tree fn = check_classfn (DECL_CONTEXT (new_friend),
5303 new_friend, NULL_TREE);
5310 input_location = saved_loc;
5314 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5315 template arguments, as for tsubst.
5317 Returns an appropriate tsubst'd friend type or error_mark_node on
5321 tsubst_friend_class (tree friend_tmpl, tree args)
5327 context = DECL_CONTEXT (friend_tmpl);
5331 if (TREE_CODE (context) == NAMESPACE_DECL)
5332 push_nested_namespace (context);
5334 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5337 /* First, we look for a class template. */
5338 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5340 /* But, if we don't find one, it might be because we're in a
5341 situation like this:
5349 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5350 for `S<int>', not the TEMPLATE_DECL. */
5351 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5353 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5354 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5357 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5359 /* The friend template has already been declared. Just
5360 check to see that the declarations match, and install any new
5361 default parameters. We must tsubst the default parameters,
5362 of course. We only need the innermost template parameters
5363 because that is all that redeclare_class_template will look
5365 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5366 > TMPL_ARGS_DEPTH (args))
5369 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5370 args, tf_error | tf_warning);
5371 redeclare_class_template (TREE_TYPE (tmpl), parms);
5374 friend_type = TREE_TYPE (tmpl);
5378 /* The friend template has not already been declared. In this
5379 case, the instantiation of the template class will cause the
5380 injection of this template into the global scope. */
5381 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5383 /* The new TMPL is not an instantiation of anything, so we
5384 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5385 the new type because that is supposed to be the corresponding
5386 template decl, i.e., TMPL. */
5387 DECL_USE_TEMPLATE (tmpl) = 0;
5388 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5389 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5390 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5391 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5393 /* Inject this template into the global scope. */
5394 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5399 if (TREE_CODE (context) == NAMESPACE_DECL)
5400 pop_nested_namespace (context);
5402 pop_nested_class ();
5408 /* Returns zero if TYPE cannot be completed later due to circularity.
5409 Otherwise returns one. */
5412 can_complete_type_without_circularity (tree type)
5414 if (type == NULL_TREE || type == error_mark_node)
5416 else if (COMPLETE_TYPE_P (type))
5418 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5419 return can_complete_type_without_circularity (TREE_TYPE (type));
5420 else if (CLASS_TYPE_P (type)
5421 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5428 instantiate_class_template (tree type)
5430 tree template, args, pattern, t, member;
5435 if (type == error_mark_node)
5436 return error_mark_node;
5438 if (TYPE_BEING_DEFINED (type)
5439 || COMPLETE_TYPE_P (type)
5440 || dependent_type_p (type))
5443 /* Figure out which template is being instantiated. */
5444 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5445 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5447 /* Figure out which arguments are being used to do the
5449 args = CLASSTYPE_TI_ARGS (type);
5451 /* Determine what specialization of the original template to
5453 t = most_specialized_class (template, args);
5454 if (t == error_mark_node)
5456 const char *str = "candidates are:";
5457 error ("ambiguous class template instantiation for %q#T", type);
5458 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5461 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5463 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5467 TYPE_BEING_DEFINED (type) = 1;
5468 return error_mark_node;
5472 pattern = TREE_TYPE (t);
5474 pattern = TREE_TYPE (template);
5476 /* If the template we're instantiating is incomplete, then clearly
5477 there's nothing we can do. */
5478 if (!COMPLETE_TYPE_P (pattern))
5481 /* If we've recursively instantiated too many templates, stop. */
5482 if (! push_tinst_level (type))
5485 /* Now we're really doing the instantiation. Mark the type as in
5486 the process of being defined. */
5487 TYPE_BEING_DEFINED (type) = 1;
5489 /* We may be in the middle of deferred access check. Disable
5491 push_deferring_access_checks (dk_no_deferred);
5493 push_to_top_level ();
5497 /* This TYPE is actually an instantiation of a partial
5498 specialization. We replace the innermost set of ARGS with
5499 the arguments appropriate for substitution. For example,
5502 template <class T> struct S {};
5503 template <class T> struct S<T*> {};
5505 and supposing that we are instantiating S<int*>, ARGS will
5506 present be {int*} but we need {int}. */
5508 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5511 /* If there were multiple levels in ARGS, replacing the
5512 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5513 want, so we make a copy first. */
5514 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5516 args = copy_node (args);
5517 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5523 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5525 /* Set the input location to the template definition. This is needed
5526 if tsubsting causes an error. */
5527 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (pattern));
5529 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5530 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5531 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5532 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5533 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5534 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5535 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5536 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5537 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5538 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5539 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5540 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5541 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5542 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5543 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5544 if (ANON_AGGR_TYPE_P (pattern))
5545 SET_ANON_AGGR_TYPE_P (type);
5547 pbinfo = TYPE_BINFO (pattern);
5549 /* We should never instantiate a nested class before its enclosing
5550 class; we need to look up the nested class by name before we can
5551 instantiate it, and that lookup should instantiate the enclosing
5553 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5554 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5555 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5557 base_list = NULL_TREE;
5558 if (BINFO_N_BASE_BINFOS (pbinfo))
5561 tree context = TYPE_CONTEXT (type);
5565 /* We must enter the scope containing the type, as that is where
5566 the accessibility of types named in dependent bases are
5568 pop_p = push_scope (context ? context : global_namespace);
5570 /* Substitute into each of the bases to determine the actual
5572 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5575 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5577 /* Substitute to figure out the base class. */
5578 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5579 if (base == error_mark_node)
5582 base_list = tree_cons (access, base, base_list);
5583 if (BINFO_VIRTUAL_P (pbase_binfo))
5584 TREE_TYPE (base_list) = integer_type_node;
5587 /* The list is now in reverse order; correct that. */
5588 base_list = nreverse (base_list);
5591 pop_scope (context ? context : global_namespace);
5593 /* Now call xref_basetypes to set up all the base-class
5595 xref_basetypes (type, base_list);
5598 /* Now that our base classes are set up, enter the scope of the
5599 class, so that name lookups into base classes, etc. will work
5600 correctly. This is precisely analogous to what we do in
5601 begin_class_definition when defining an ordinary non-template
5605 /* Now members are processed in the order of declaration. */
5606 for (member = CLASSTYPE_DECL_LIST (pattern);
5607 member; member = TREE_CHAIN (member))
5609 tree t = TREE_VALUE (member);
5611 if (TREE_PURPOSE (member))
5615 /* Build new CLASSTYPE_NESTED_UTDS. */
5618 tree name = TYPE_IDENTIFIER (tag);
5620 bool class_template_p;
5622 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5623 && TYPE_LANG_SPECIFIC (tag)
5624 && CLASSTYPE_IS_TEMPLATE (tag));
5625 /* If the member is a class template, then -- even after
5626 substitution -- there may be dependent types in the
5627 template argument list for the class. We increment
5628 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5629 that function will assume that no types are dependent
5630 when outside of a template. */
5631 if (class_template_p)
5632 ++processing_template_decl;
5633 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5634 if (class_template_p)
5635 --processing_template_decl;
5636 if (newtag == error_mark_node)
5639 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5641 if (class_template_p)
5642 /* Unfortunately, lookup_template_class sets
5643 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5644 instantiation (i.e., for the type of a member
5645 template class nested within a template class.)
5646 This behavior is required for
5647 maybe_process_partial_specialization to work
5648 correctly, but is not accurate in this case;
5649 the TAG is not an instantiation of anything.
5650 (The corresponding TEMPLATE_DECL is an
5651 instantiation, but the TYPE is not.) */
5652 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5654 /* Now, we call pushtag to put this NEWTAG into the scope of
5655 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5656 pushtag calling push_template_decl. We don't have to do
5657 this for enums because it will already have been done in
5660 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5661 pushtag (name, newtag, /*globalize=*/0);
5664 else if (TREE_CODE (t) == FUNCTION_DECL
5665 || DECL_FUNCTION_TEMPLATE_P (t))
5667 /* Build new TYPE_METHODS. */
5670 if (TREE_CODE (t) == TEMPLATE_DECL)
5671 ++processing_template_decl;
5672 r = tsubst (t, args, tf_error, NULL_TREE);
5673 if (TREE_CODE (t) == TEMPLATE_DECL)
5674 --processing_template_decl;
5675 set_current_access_from_decl (r);
5676 grok_special_member_properties (r);
5677 finish_member_declaration (r);
5681 /* Build new TYPE_FIELDS. */
5683 if (TREE_CODE (t) != CONST_DECL)
5687 /* The the file and line for this declaration, to
5688 assist in error message reporting. Since we
5689 called push_tinst_level above, we don't need to
5691 input_location = DECL_SOURCE_LOCATION (t);
5693 if (TREE_CODE (t) == TEMPLATE_DECL)
5694 ++processing_template_decl;
5695 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5696 if (TREE_CODE (t) == TEMPLATE_DECL)
5697 --processing_template_decl;
5698 if (TREE_CODE (r) == VAR_DECL)
5702 if (DECL_INITIALIZED_IN_CLASS_P (r))
5703 init = tsubst_expr (DECL_INITIAL (t), args,
5704 tf_error | tf_warning, NULL_TREE);
5708 finish_static_data_member_decl
5709 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5711 if (DECL_INITIALIZED_IN_CLASS_P (r))
5712 check_static_variable_definition (r, TREE_TYPE (r));
5714 else if (TREE_CODE (r) == FIELD_DECL)
5716 /* Determine whether R has a valid type and can be
5717 completed later. If R is invalid, then it is
5718 replaced by error_mark_node so that it will not be
5719 added to TYPE_FIELDS. */
5720 tree rtype = TREE_TYPE (r);
5721 if (can_complete_type_without_circularity (rtype))
5722 complete_type (rtype);
5724 if (!COMPLETE_TYPE_P (rtype))
5726 cxx_incomplete_type_error (r, rtype);
5727 r = error_mark_node;
5731 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5732 such a thing will already have been added to the field
5733 list by tsubst_enum in finish_member_declaration in the
5734 CLASSTYPE_NESTED_UTDS case above. */
5735 if (!(TREE_CODE (r) == TYPE_DECL
5736 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5737 && DECL_ARTIFICIAL (r)))
5739 set_current_access_from_decl (r);
5740 finish_member_declaration (r);
5747 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5749 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5751 tree friend_type = t;
5752 bool adjust_processing_template_decl = false;
5754 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5756 friend_type = tsubst_friend_class (friend_type, args);
5757 adjust_processing_template_decl = true;
5759 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5761 friend_type = tsubst (friend_type, args,
5762 tf_error | tf_warning, NULL_TREE);
5763 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5764 friend_type = TREE_TYPE (friend_type);
5765 adjust_processing_template_decl = true;
5767 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5769 friend_type = tsubst (friend_type, args,
5770 tf_error | tf_warning, NULL_TREE);
5771 /* Bump processing_template_decl for correct
5772 dependent_type_p calculation. */
5773 ++processing_template_decl;
5774 if (dependent_type_p (friend_type))
5775 adjust_processing_template_decl = true;
5776 --processing_template_decl;
5778 else if (uses_template_parms (friend_type))
5779 friend_type = tsubst (friend_type, args,
5780 tf_error | tf_warning, NULL_TREE);
5781 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5782 friend_type = friend_type;
5785 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5787 /* The call to xref_tag_from_type does injection for friend
5789 push_nested_namespace (ns);
5791 xref_tag_from_type (friend_type, NULL_TREE, 1);
5792 pop_nested_namespace (ns);
5795 if (adjust_processing_template_decl)
5796 /* Trick make_friend_class into realizing that the friend
5797 we're adding is a template, not an ordinary class. It's
5798 important that we use make_friend_class since it will
5799 perform some error-checking and output cross-reference
5801 ++processing_template_decl;
5803 if (friend_type != error_mark_node)
5804 make_friend_class (type, friend_type, /*complain=*/false);
5806 if (adjust_processing_template_decl)
5807 --processing_template_decl;
5811 /* Build new DECL_FRIENDLIST. */
5814 if (TREE_CODE (t) == TEMPLATE_DECL)
5816 ++processing_template_decl;
5817 push_deferring_access_checks (dk_no_check);
5820 r = tsubst_friend_function (t, args);
5821 add_friend (type, r, /*complain=*/false);
5822 if (TREE_CODE (t) == TEMPLATE_DECL)
5824 pop_deferring_access_checks ();
5825 --processing_template_decl;
5831 /* Set the file and line number information to whatever is given for
5832 the class itself. This puts error messages involving generated
5833 implicit functions at a predictable point, and the same point
5834 that would be used for non-template classes. */
5835 typedecl = TYPE_MAIN_DECL (type);
5836 input_location = DECL_SOURCE_LOCATION (typedecl);
5838 unreverse_member_declarations (type);
5839 finish_struct_1 (type);
5840 TYPE_BEING_DEFINED (type) = 0;
5842 /* Now that the class is complete, instantiate default arguments for
5843 any member functions. We don't do this earlier because the
5844 default arguments may reference members of the class. */
5845 if (!PRIMARY_TEMPLATE_P (template))
5846 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5847 if (TREE_CODE (t) == FUNCTION_DECL
5848 /* Implicitly generated member functions will not have template
5849 information; they are not instantiations, but instead are
5850 created "fresh" for each instantiation. */
5851 && DECL_TEMPLATE_INFO (t))
5852 tsubst_default_arguments (t);
5855 pop_from_top_level ();
5856 pop_deferring_access_checks ();
5859 /* The vtable for a template class can be emitted in any translation
5860 unit in which the class is instantiated. When there is no key
5861 method, however, finish_struct_1 will already have added TYPE to
5862 the keyed_classes list. */
5863 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5864 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5870 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5876 else if (TYPE_P (t))
5877 r = tsubst (t, args, complain, in_decl);
5880 r = tsubst_expr (t, args, complain, in_decl);
5882 if (!uses_template_parms (r))
5884 /* Sometimes, one of the args was an expression involving a
5885 template constant parameter, like N - 1. Now that we've
5886 tsubst'd, we might have something like 2 - 1. This will
5887 confuse lookup_template_class, so we do constant folding
5888 here. We have to unset processing_template_decl, to fool
5889 tsubst_copy_and_build() into building an actual tree. */
5891 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5892 as simple as it's going to get, and trying to reprocess
5893 the trees will break. Once tsubst_expr et al DTRT for
5894 non-dependent exprs, this code can go away, as the type
5895 will always be set. */
5898 int saved_processing_template_decl = processing_template_decl;
5899 processing_template_decl = 0;
5900 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5901 tf_error, /*in_decl=*/NULL_TREE,
5902 /*function_p=*/false);
5903 processing_template_decl = saved_processing_template_decl;
5911 /* Substitute ARGS into the vector or list of template arguments T. */
5914 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5916 int len = TREE_VEC_LENGTH (t);
5917 int need_new = 0, i;
5918 tree *elts = alloca (len * sizeof (tree));
5920 for (i = 0; i < len; i++)
5922 tree orig_arg = TREE_VEC_ELT (t, i);
5925 if (TREE_CODE (orig_arg) == TREE_VEC)
5926 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5928 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5930 if (new_arg == error_mark_node)
5931 return error_mark_node;
5934 if (new_arg != orig_arg)
5941 t = make_tree_vec (len);
5942 for (i = 0; i < len; i++)
5943 TREE_VEC_ELT (t, i) = elts[i];
5948 /* Return the result of substituting ARGS into the template parameters
5949 given by PARMS. If there are m levels of ARGS and m + n levels of
5950 PARMS, then the result will contain n levels of PARMS. For
5951 example, if PARMS is `template <class T> template <class U>
5952 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5953 result will be `template <int*, double, class V>'. */
5956 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5961 for (new_parms = &r;
5962 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5963 new_parms = &(TREE_CHAIN (*new_parms)),
5964 parms = TREE_CHAIN (parms))
5967 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5970 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5972 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5973 tree default_value = TREE_PURPOSE (tuple);
5974 tree parm_decl = TREE_VALUE (tuple);
5976 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5977 default_value = tsubst_template_arg (default_value, args,
5978 complain, NULL_TREE);
5980 tuple = build_tree_list (default_value, parm_decl);
5981 TREE_VEC_ELT (new_vec, i) = tuple;
5985 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
5986 - TMPL_ARGS_DEPTH (args)),
5987 new_vec, NULL_TREE);
5993 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5994 type T. If T is not an aggregate or enumeration type, it is
5995 handled as if by tsubst. IN_DECL is as for tsubst. If
5996 ENTERING_SCOPE is nonzero, T is the context for a template which
5997 we are presently tsubst'ing. Return the substituted value. */
6000 tsubst_aggr_type (tree t,
6002 tsubst_flags_t complain,
6009 switch (TREE_CODE (t))
6012 if (TYPE_PTRMEMFUNC_P (t))
6013 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6015 /* Else fall through. */
6018 if (TYPE_TEMPLATE_INFO (t))
6024 /* First, determine the context for the type we are looking
6026 context = TYPE_CONTEXT (t);
6028 context = tsubst_aggr_type (context, args, complain,
6029 in_decl, /*entering_scope=*/1);
6031 /* Then, figure out what arguments are appropriate for the
6032 type we are trying to find. For example, given:
6034 template <class T> struct S;
6035 template <class T, class U> void f(T, U) { S<U> su; }
6037 and supposing that we are instantiating f<int, double>,
6038 then our ARGS will be {int, double}, but, when looking up
6039 S we only want {double}. */
6040 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6042 if (argvec == error_mark_node)
6043 return error_mark_node;
6045 r = lookup_template_class (t, argvec, in_decl, context,
6046 entering_scope, complain);
6048 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6051 /* This is not a template type, so there's nothing to do. */
6055 return tsubst (t, args, complain, in_decl);
6059 /* Substitute into the default argument ARG (a default argument for
6060 FN), which has the indicated TYPE. */
6063 tsubst_default_argument (tree fn, tree type, tree arg)
6065 tree saved_class_ptr = NULL_TREE;
6066 tree saved_class_ref = NULL_TREE;
6068 /* This default argument came from a template. Instantiate the
6069 default argument here, not in tsubst. In the case of
6078 we must be careful to do name lookup in the scope of S<T>,
6079 rather than in the current class. */
6080 push_access_scope (fn);
6081 /* The default argument expression should not be considered to be
6082 within the scope of FN. Since push_access_scope sets
6083 current_function_decl, we must explicitly clear it here. */
6084 current_function_decl = NULL_TREE;
6085 /* The "this" pointer is not valid in a default argument. */
6088 saved_class_ptr = current_class_ptr;
6089 cp_function_chain->x_current_class_ptr = NULL_TREE;
6090 saved_class_ref = current_class_ref;
6091 cp_function_chain->x_current_class_ref = NULL_TREE;
6094 push_deferring_access_checks(dk_no_deferred);
6095 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6096 tf_error | tf_warning, NULL_TREE);
6097 pop_deferring_access_checks();
6099 /* Restore the "this" pointer. */
6102 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6103 cp_function_chain->x_current_class_ref = saved_class_ref;
6106 pop_access_scope (fn);
6108 /* Make sure the default argument is reasonable. */
6109 arg = check_default_argument (type, arg);
6114 /* Substitute into all the default arguments for FN. */
6117 tsubst_default_arguments (tree fn)
6122 tmpl_args = DECL_TI_ARGS (fn);
6124 /* If this function is not yet instantiated, we certainly don't need
6125 its default arguments. */
6126 if (uses_template_parms (tmpl_args))
6129 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6131 arg = TREE_CHAIN (arg))
6132 if (TREE_PURPOSE (arg))
6133 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6135 TREE_PURPOSE (arg));
6138 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
6139 (already computed) substitution of ARGS into TREE_TYPE (T), if
6140 appropriate. Return the result of the substitution. Issue error
6141 and warning messages under control of COMPLAIN. */
6144 tsubst_decl (tree t, tree args, tree type, tsubst_flags_t complain)
6146 location_t saved_loc;
6150 /* Set the filename and linenumber to improve error-reporting. */
6151 saved_loc = input_location;
6152 input_location = DECL_SOURCE_LOCATION (t);
6154 switch (TREE_CODE (t))
6158 /* We can get here when processing a member template function
6159 of a template class. */
6160 tree decl = DECL_TEMPLATE_RESULT (t);
6162 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
6164 if (!is_template_template_parm)
6166 /* We might already have an instance of this template.
6167 The ARGS are for the surrounding class type, so the
6168 full args contain the tsubst'd args for the context,
6169 plus the innermost args from the template decl. */
6170 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6171 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6172 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6175 full_args = tsubst_template_args (tmpl_args, args,
6178 /* tsubst_template_args doesn't copy the vector if
6179 nothing changed. But, *something* should have
6181 gcc_assert (full_args != tmpl_args);
6183 spec = retrieve_specialization (t, full_args,
6184 /*class_specializations_p=*/true);
6185 if (spec != NULL_TREE)
6192 /* Make a new template decl. It will be similar to the
6193 original, but will record the current template arguments.
6194 We also create a new function declaration, which is just
6195 like the old one, but points to this new template, rather
6196 than the old one. */
6198 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6199 TREE_CHAIN (r) = NULL_TREE;
6201 if (is_template_template_parm)
6203 tree new_decl = tsubst (decl, args, complain, in_decl);
6204 DECL_TEMPLATE_RESULT (r) = new_decl;
6205 TREE_TYPE (r) = TREE_TYPE (new_decl);
6210 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6212 /*entering_scope=*/1);
6213 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6215 if (TREE_CODE (decl) == TYPE_DECL)
6217 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6218 if (new_type == error_mark_node)
6219 return error_mark_node;
6221 TREE_TYPE (r) = new_type;
6222 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6223 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6224 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6228 tree new_decl = tsubst (decl, args, complain, in_decl);
6229 if (new_decl == error_mark_node)
6230 return error_mark_node;
6232 DECL_TEMPLATE_RESULT (r) = new_decl;
6233 DECL_TI_TEMPLATE (new_decl) = r;
6234 TREE_TYPE (r) = TREE_TYPE (new_decl);
6235 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6238 SET_DECL_IMPLICIT_INSTANTIATION (r);
6239 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6240 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6242 /* The template parameters for this new template are all the
6243 template parameters for the old template, except the
6244 outermost level of parameters. */
6245 DECL_TEMPLATE_PARMS (r)
6246 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6249 if (PRIMARY_TEMPLATE_P (t))
6250 DECL_PRIMARY_TEMPLATE (r) = r;
6252 if (TREE_CODE (decl) != TYPE_DECL)
6253 /* Record this non-type partial instantiation. */
6254 register_specialization (r, t,
6255 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6262 tree argvec = NULL_TREE;
6269 /* Nobody should be tsubst'ing into non-template functions. */
6270 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6272 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6277 /* If T is not dependent, just return it. We have to
6278 increment PROCESSING_TEMPLATE_DECL because
6279 value_dependent_expression_p assumes that nothing is
6280 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6281 ++processing_template_decl;
6282 dependent_p = value_dependent_expression_p (t);
6283 --processing_template_decl;
6287 /* Calculate the most general template of which R is a
6288 specialization, and the complete set of arguments used to
6290 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6291 argvec = tsubst_template_args (DECL_TI_ARGS
6292 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6293 args, complain, in_decl);
6295 /* Check to see if we already have this specialization. */
6296 spec = retrieve_specialization (gen_tmpl, argvec,
6297 /*class_specializations_p=*/false);
6305 /* We can see more levels of arguments than parameters if
6306 there was a specialization of a member template, like
6309 template <class T> struct S { template <class U> void f(); }
6310 template <> template <class U> void S<int>::f(U);
6312 Here, we'll be substituting into the specialization,
6313 because that's where we can find the code we actually
6314 want to generate, but we'll have enough arguments for
6315 the most general template.
6317 We also deal with the peculiar case:
6319 template <class T> struct S {
6320 template <class U> friend void f();
6322 template <class U> void f() {}
6324 template void f<double>();
6326 Here, the ARGS for the instantiation of will be {int,
6327 double}. But, we only need as many ARGS as there are
6328 levels of template parameters in CODE_PATTERN. We are
6329 careful not to get fooled into reducing the ARGS in
6332 template <class T> struct S { template <class U> void f(U); }
6333 template <class T> template <> void S<T>::f(int) {}
6335 which we can spot because the pattern will be a
6336 specialization in this case. */
6337 args_depth = TMPL_ARGS_DEPTH (args);
6339 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6340 if (args_depth > parms_depth
6341 && !DECL_TEMPLATE_SPECIALIZATION (t))
6342 args = get_innermost_template_args (args, parms_depth);
6346 /* This special case arises when we have something like this:
6348 template <class T> struct S {
6349 friend void f<int>(int, double);
6352 Here, the DECL_TI_TEMPLATE for the friend declaration
6353 will be an IDENTIFIER_NODE. We are being called from
6354 tsubst_friend_function, and we want only to create a
6355 new decl (R) with appropriate types so that we can call
6356 determine_specialization. */
6357 gen_tmpl = NULL_TREE;
6360 if (DECL_CLASS_SCOPE_P (t))
6362 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6366 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6367 complain, t, /*entering_scope=*/1);
6372 ctx = DECL_CONTEXT (t);
6374 type = tsubst (type, args, complain, in_decl);
6375 if (type == error_mark_node)
6376 return error_mark_node;
6378 /* We do NOT check for matching decls pushed separately at this
6379 point, as they may not represent instantiations of this
6380 template, and in any case are considered separate under the
6383 DECL_USE_TEMPLATE (r) = 0;
6384 TREE_TYPE (r) = type;
6385 /* Clear out the mangled name and RTL for the instantiation. */
6386 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6387 SET_DECL_RTL (r, NULL_RTX);
6388 DECL_INITIAL (r) = NULL_TREE;
6389 DECL_CONTEXT (r) = ctx;
6391 if (member && DECL_CONV_FN_P (r))
6392 /* Type-conversion operator. Reconstruct the name, in
6393 case it's the name of one of the template's parameters. */
6394 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6396 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6398 DECL_RESULT (r) = NULL_TREE;
6400 TREE_STATIC (r) = 0;
6401 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6402 DECL_EXTERNAL (r) = 1;
6403 /* If this is an instantiation of a function with internal
6404 linkage, we already know what object file linkage will be
6405 assigned to the instantiation. */
6406 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6407 DECL_DEFER_OUTPUT (r) = 0;
6408 TREE_CHAIN (r) = NULL_TREE;
6409 DECL_PENDING_INLINE_INFO (r) = 0;
6410 DECL_PENDING_INLINE_P (r) = 0;
6411 DECL_SAVED_TREE (r) = NULL_TREE;
6413 if (DECL_CLONED_FUNCTION (r))
6415 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6417 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6418 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6421 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6422 this in the special friend case mentioned above where
6423 GEN_TMPL is NULL. */
6426 DECL_TEMPLATE_INFO (r)
6427 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6428 SET_DECL_IMPLICIT_INSTANTIATION (r);
6429 register_specialization (r, gen_tmpl, argvec);
6431 /* We're not supposed to instantiate default arguments
6432 until they are called, for a template. But, for a
6435 template <class T> void f ()
6436 { extern void g(int i = T()); }
6438 we should do the substitution when the template is
6439 instantiated. We handle the member function case in
6440 instantiate_class_template since the default arguments
6441 might refer to other members of the class. */
6443 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6444 && !uses_template_parms (argvec))
6445 tsubst_default_arguments (r);
6448 /* Copy the list of befriending classes. */
6449 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6451 friends = &TREE_CHAIN (*friends))
6453 *friends = copy_node (*friends);
6454 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6459 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6461 maybe_retrofit_in_chrg (r);
6462 if (DECL_CONSTRUCTOR_P (r))
6463 grok_ctor_properties (ctx, r);
6464 /* If this is an instantiation of a member template, clone it.
6465 If it isn't, that'll be handled by
6466 clone_constructors_and_destructors. */
6467 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6468 clone_function_decl (r, /*update_method_vec_p=*/0);
6470 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6471 grok_op_properties (r, DECL_FRIEND_P (r),
6472 (complain & tf_error) != 0);
6474 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6475 SET_DECL_FRIEND_CONTEXT (r,
6476 tsubst (DECL_FRIEND_CONTEXT (t),
6477 args, complain, in_decl));
6484 if (DECL_TEMPLATE_PARM_P (t))
6485 SET_DECL_TEMPLATE_PARM_P (r);
6487 TREE_TYPE (r) = type;
6488 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6490 if (DECL_INITIAL (r))
6492 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6493 DECL_INITIAL (r) = TREE_TYPE (r);
6495 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6499 DECL_CONTEXT (r) = NULL_TREE;
6501 if (!DECL_TEMPLATE_PARM_P (r))
6502 DECL_ARG_TYPE (r) = type_passed_as (type);
6504 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6505 complain, TREE_CHAIN (t));
6512 TREE_TYPE (r) = type;
6513 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6515 /* We don't have to set DECL_CONTEXT here; it is set by
6516 finish_member_declaration. */
6517 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6519 TREE_CHAIN (r) = NULL_TREE;
6520 if (VOID_TYPE_P (type))
6521 cp_error_at ("instantiation of %qD as type %qT", r, type);
6528 /* It is not a dependent using decl any more. */
6529 TREE_TYPE (r) = void_type_node;
6531 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6533 = tsubst_copy (DECL_NAME (t), args, complain, in_decl);
6534 TREE_CHAIN (r) = NULL_TREE;
6539 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6540 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6542 /* If this is the canonical decl, we don't have to mess with
6543 instantiations, and often we can't (for typename, template
6544 type parms and such). Note that TYPE_NAME is not correct for
6545 the above test if we've copied the type for a typedef. */
6546 r = TYPE_NAME (type);
6554 tree argvec = NULL_TREE;
6555 tree gen_tmpl = NULL_TREE;
6557 tree tmpl = NULL_TREE;
6561 /* Assume this is a non-local variable. */
6564 if (TYPE_P (CP_DECL_CONTEXT (t)))
6565 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6567 in_decl, /*entering_scope=*/1);
6568 else if (DECL_NAMESPACE_SCOPE_P (t))
6569 ctx = DECL_CONTEXT (t);
6572 /* Subsequent calls to pushdecl will fill this in. */
6577 /* Check to see if we already have this specialization. */
6580 tmpl = DECL_TI_TEMPLATE (t);
6581 gen_tmpl = most_general_template (tmpl);
6582 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6583 spec = retrieve_specialization (gen_tmpl, argvec,
6584 /*class_specializations_p=*/false);
6587 spec = retrieve_local_specialization (t);
6596 if (TREE_CODE (r) == VAR_DECL)
6598 type = complete_type (type);
6599 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6600 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6601 type = check_var_type (DECL_NAME (r), type);
6603 else if (DECL_SELF_REFERENCE_P (t))
6604 SET_DECL_SELF_REFERENCE_P (r);
6605 TREE_TYPE (r) = type;
6606 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6607 DECL_CONTEXT (r) = ctx;
6608 /* Clear out the mangled name and RTL for the instantiation. */
6609 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6610 SET_DECL_RTL (r, NULL_RTX);
6612 /* Don't try to expand the initializer until someone tries to use
6613 this variable; otherwise we run into circular dependencies. */
6614 DECL_INITIAL (r) = NULL_TREE;
6615 SET_DECL_RTL (r, NULL_RTX);
6616 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6618 /* Even if the original location is out of scope, the newly
6619 substituted one is not. */
6620 if (TREE_CODE (r) == VAR_DECL)
6622 DECL_DEAD_FOR_LOCAL (r) = 0;
6623 DECL_INITIALIZED_P (r) = 0;
6628 /* A static data member declaration is always marked
6629 external when it is declared in-class, even if an
6630 initializer is present. We mimic the non-template
6632 DECL_EXTERNAL (r) = 1;
6634 register_specialization (r, gen_tmpl, argvec);
6635 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6636 SET_DECL_IMPLICIT_INSTANTIATION (r);
6639 register_local_specialization (r, t);
6641 TREE_CHAIN (r) = NULL_TREE;
6650 /* Restore the file and line information. */
6651 input_location = saved_loc;
6656 /* Substitute into the ARG_TYPES of a function type. */
6659 tsubst_arg_types (tree arg_types,
6661 tsubst_flags_t complain,
6664 tree remaining_arg_types;
6667 if (!arg_types || arg_types == void_list_node)
6670 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6671 args, complain, in_decl);
6672 if (remaining_arg_types == error_mark_node)
6673 return error_mark_node;
6675 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6676 if (type == error_mark_node)
6677 return error_mark_node;
6678 if (VOID_TYPE_P (type))
6680 if (complain & tf_error)
6682 error ("invalid parameter type %qT", type);
6684 cp_error_at ("in declaration %qD", in_decl);
6686 return error_mark_node;
6689 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6690 top-level qualifiers as required. */
6691 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6693 /* Note that we do not substitute into default arguments here. The
6694 standard mandates that they be instantiated only when needed,
6695 which is done in build_over_call. */
6696 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6697 remaining_arg_types);
6701 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6702 *not* handle the exception-specification for FNTYPE, because the
6703 initial substitution of explicitly provided template parameters
6704 during argument deduction forbids substitution into the
6705 exception-specification:
6709 All references in the function type of the function template to the
6710 corresponding template parameters are replaced by the specified tem-
6711 plate argument values. If a substitution in a template parameter or
6712 in the function type of the function template results in an invalid
6713 type, type deduction fails. [Note: The equivalent substitution in
6714 exception specifications is done only when the function is instanti-
6715 ated, at which point a program is ill-formed if the substitution
6716 results in an invalid type.] */
6719 tsubst_function_type (tree t,
6721 tsubst_flags_t complain,
6728 /* The TYPE_CONTEXT is not used for function/method types. */
6729 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6731 /* Substitute the return type. */
6732 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6733 if (return_type == error_mark_node)
6734 return error_mark_node;
6736 /* Substitute the argument types. */
6737 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6739 if (arg_types == error_mark_node)
6740 return error_mark_node;
6742 /* Construct a new type node and return it. */
6743 if (TREE_CODE (t) == FUNCTION_TYPE)
6744 fntype = build_function_type (return_type, arg_types);
6747 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6748 if (! IS_AGGR_TYPE (r))
6752 Type deduction may fail for any of the following
6755 -- Attempting to create "pointer to member of T" when T
6756 is not a class type. */
6757 if (complain & tf_error)
6758 error ("creating pointer to member function of non-class type %qT",
6760 return error_mark_node;
6763 fntype = build_method_type_directly (r, return_type,
6764 TREE_CHAIN (arg_types));
6766 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6767 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6772 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6773 ARGS into that specification, and return the substituted
6774 specification. If there is no specification, return NULL_TREE. */
6777 tsubst_exception_specification (tree fntype,
6779 tsubst_flags_t complain,
6785 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6786 new_specs = NULL_TREE;
6789 if (! TREE_VALUE (specs))
6795 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6796 if (spec == error_mark_node)
6798 new_specs = add_exception_specifier (new_specs, spec, complain);
6799 specs = TREE_CHAIN (specs);
6805 /* Substitute into the PARMS of a call-declarator. */
6808 tsubst_call_declarator_parms (tree parms,
6810 tsubst_flags_t complain,
6817 if (!parms || parms == void_list_node)
6820 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6821 args, complain, in_decl);
6823 /* Figure out the type of this parameter. */
6824 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6826 /* Figure out the default argument as well. Note that we use
6827 tsubst_expr since the default argument is really an expression. */
6828 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6830 /* Chain this parameter on to the front of those we have already
6831 processed. We don't use hash_tree_cons because that function
6832 doesn't check TREE_PARMLIST. */
6833 new_parms = tree_cons (defarg, type, new_parms);
6838 /* Take the tree structure T and replace template parameters used
6839 therein with the argument vector ARGS. IN_DECL is an associated
6840 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6841 Issue error and warning messages under control of COMPLAIN. Note
6842 that we must be relatively non-tolerant of extensions here, in
6843 order to preserve conformance; if we allow substitutions that
6844 should not be allowed, we may allow argument deductions that should
6845 not succeed, and therefore report ambiguous overload situations
6846 where there are none. In theory, we could allow the substitution,
6847 but indicate that it should have failed, and allow our caller to
6848 make sure that the right thing happens, but we don't try to do this
6851 This function is used for dealing with types, decls and the like;
6852 for expressions, use tsubst_expr or tsubst_copy. */
6855 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6859 if (t == NULL_TREE || t == error_mark_node
6860 || t == integer_type_node
6861 || t == void_type_node
6862 || t == char_type_node
6863 || t == unknown_type_node
6864 || TREE_CODE (t) == NAMESPACE_DECL)
6867 if (TREE_CODE (t) == IDENTIFIER_NODE)
6868 type = IDENTIFIER_TYPE_VALUE (t);
6870 type = TREE_TYPE (t);
6872 gcc_assert (type != unknown_type_node);
6874 if (type && TREE_CODE (t) != FUNCTION_DECL
6875 && TREE_CODE (t) != TYPENAME_TYPE
6876 && TREE_CODE (t) != TEMPLATE_DECL
6877 && TREE_CODE (t) != IDENTIFIER_NODE
6878 && TREE_CODE (t) != FUNCTION_TYPE
6879 && TREE_CODE (t) != METHOD_TYPE)
6880 type = tsubst (type, args, complain, in_decl);
6881 if (type == error_mark_node)
6882 return error_mark_node;
6885 return tsubst_decl (t, args, type, complain);
6887 switch (TREE_CODE (t))
6892 return tsubst_aggr_type (t, args, complain, in_decl,
6893 /*entering_scope=*/0);
6896 case IDENTIFIER_NODE:
6908 if (t == integer_type_node)
6911 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6912 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6916 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6918 /* The array dimension behaves like a non-type template arg,
6919 in that we want to fold it as much as possible. */
6920 max = tsubst_template_arg (omax, args, complain, in_decl);
6921 if (!processing_template_decl)
6922 max = decl_constant_value (max);
6924 if (integer_zerop (omax))
6926 /* Still allow an explicit array of size zero. */
6928 pedwarn ("creating array with size zero");
6930 else if (integer_zerop (max)
6931 || (TREE_CODE (max) == INTEGER_CST
6932 && INT_CST_LT (max, integer_zero_node)))
6936 Type deduction may fail for any of the following
6939 Attempting to create an array with a size that is
6940 zero or negative. */
6941 if (complain & tf_error)
6942 error ("creating array with size zero (%qE)", max);
6944 return error_mark_node;
6947 return compute_array_index_type (NULL_TREE, max);
6950 case TEMPLATE_TYPE_PARM:
6951 case TEMPLATE_TEMPLATE_PARM:
6952 case BOUND_TEMPLATE_TEMPLATE_PARM:
6953 case TEMPLATE_PARM_INDEX:
6958 tree arg = NULL_TREE;
6962 gcc_assert (TREE_VEC_LENGTH (args) > 0);
6963 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6964 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6965 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6967 idx = TEMPLATE_TYPE_IDX (t);
6968 level = TEMPLATE_TYPE_LEVEL (t);
6972 idx = TEMPLATE_PARM_IDX (t);
6973 level = TEMPLATE_PARM_LEVEL (t);
6976 levels = TMPL_ARGS_DEPTH (args);
6977 if (level <= levels)
6978 arg = TMPL_ARG (args, level, idx);
6980 if (arg == error_mark_node)
6981 return error_mark_node;
6982 else if (arg != NULL_TREE)
6984 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6986 gcc_assert (TYPE_P (arg));
6987 return cp_build_qualified_type_real
6988 (arg, cp_type_quals (arg) | cp_type_quals (t),
6989 complain | tf_ignore_bad_quals);
6991 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6993 /* We are processing a type constructed from a
6994 template template parameter. */
6995 tree argvec = tsubst (TYPE_TI_ARGS (t),
6996 args, complain, in_decl);
6997 if (argvec == error_mark_node)
6998 return error_mark_node;
7000 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7001 are resolving nested-types in the signature of a
7002 member function templates. Otherwise ARG is a
7003 TEMPLATE_DECL and is the real template to be
7005 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7006 arg = TYPE_NAME (arg);
7008 r = lookup_template_class (arg,
7011 /*entering_scope=*/0,
7013 return cp_build_qualified_type_real
7014 (r, TYPE_QUALS (t), complain);
7017 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7022 /* This can happen during the attempted tsubst'ing in
7023 unify. This means that we don't yet have any information
7024 about the template parameter in question. */
7027 /* If we get here, we must have been looking at a parm for a
7028 more deeply nested template. Make a new version of this
7029 template parameter, but with a lower level. */
7030 switch (TREE_CODE (t))
7032 case TEMPLATE_TYPE_PARM:
7033 case TEMPLATE_TEMPLATE_PARM:
7034 case BOUND_TEMPLATE_TEMPLATE_PARM:
7035 if (cp_type_quals (t))
7037 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7038 r = cp_build_qualified_type_real
7039 (r, cp_type_quals (t),
7040 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7041 ? tf_ignore_bad_quals : 0));
7046 TEMPLATE_TYPE_PARM_INDEX (r)
7047 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7049 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7050 TYPE_MAIN_VARIANT (r) = r;
7051 TYPE_POINTER_TO (r) = NULL_TREE;
7052 TYPE_REFERENCE_TO (r) = NULL_TREE;
7054 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7056 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7058 if (argvec == error_mark_node)
7059 return error_mark_node;
7061 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7062 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7067 case TEMPLATE_PARM_INDEX:
7068 r = reduce_template_parm_level (t, type, levels);
7080 tree purpose, value, chain;
7082 if (t == void_list_node)
7085 purpose = TREE_PURPOSE (t);
7088 purpose = tsubst (purpose, args, complain, in_decl);
7089 if (purpose == error_mark_node)
7090 return error_mark_node;
7092 value = TREE_VALUE (t);
7095 value = tsubst (value, args, complain, in_decl);
7096 if (value == error_mark_node)
7097 return error_mark_node;
7099 chain = TREE_CHAIN (t);
7100 if (chain && chain != void_type_node)
7102 chain = tsubst (chain, args, complain, in_decl);
7103 if (chain == error_mark_node)
7104 return error_mark_node;
7106 if (purpose == TREE_PURPOSE (t)
7107 && value == TREE_VALUE (t)
7108 && chain == TREE_CHAIN (t))
7110 return hash_tree_cons (purpose, value, chain);
7114 /* We should never be tsubsting a binfo. */
7118 /* A vector of template arguments. */
7120 return tsubst_template_args (t, args, complain, in_decl);
7123 case REFERENCE_TYPE:
7125 enum tree_code code;
7127 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7130 code = TREE_CODE (t);
7135 Type deduction may fail for any of the following
7138 -- Attempting to create a pointer to reference type.
7139 -- Attempting to create a reference to a reference type or
7140 a reference to void. */
7141 if (TREE_CODE (type) == REFERENCE_TYPE
7142 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7144 static location_t last_loc;
7146 /* We keep track of the last time we issued this error
7147 message to avoid spewing a ton of messages during a
7148 single bad template instantiation. */
7149 if (complain & tf_error
7150 #ifdef USE_MAPPED_LOCATION
7151 && last_loc != input_location
7153 && (last_loc.line != input_line
7154 || last_loc.file != input_filename)
7158 if (TREE_CODE (type) == VOID_TYPE)
7159 error ("forming reference to void");
7161 error ("forming %s to reference type %qT",
7162 (code == POINTER_TYPE) ? "pointer" : "reference",
7164 last_loc = input_location;
7167 return error_mark_node;
7169 else if (code == POINTER_TYPE)
7171 r = build_pointer_type (type);
7172 if (TREE_CODE (type) == METHOD_TYPE)
7173 r = build_ptrmemfunc_type (r);
7176 r = build_reference_type (type);
7177 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7179 if (r != error_mark_node)
7180 /* Will this ever be needed for TYPE_..._TO values? */
7187 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7188 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7192 Type deduction may fail for any of the following
7195 -- Attempting to create "pointer to member of T" when T
7196 is not a class type. */
7197 if (complain & tf_error)
7198 error ("creating pointer to member of non-class type %qT", r);
7199 return error_mark_node;
7201 if (TREE_CODE (type) == REFERENCE_TYPE)
7203 if (complain & tf_error)
7204 error ("creating pointer to member reference type %qT", type);
7206 return error_mark_node;
7208 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7209 if (TREE_CODE (type) == FUNCTION_TYPE)
7211 /* This is really a method type. The cv qualifiers of the
7212 this pointer should _not_ be determined by the cv
7213 qualifiers of the class type. They should be held
7214 somewhere in the FUNCTION_TYPE, but we don't do that at
7215 the moment. Consider
7216 typedef void (Func) () const;
7218 template <typename T1> void Foo (Func T1::*);
7223 method_type = build_method_type_directly (TYPE_MAIN_VARIANT (r),
7225 TYPE_ARG_TYPES (type));
7226 return build_ptrmemfunc_type (build_pointer_type (method_type));
7229 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7238 fntype = tsubst_function_type (t, args, complain, in_decl);
7239 if (fntype == error_mark_node)
7240 return error_mark_node;
7242 /* Substitute the exception specification. */
7243 specs = tsubst_exception_specification (t, args, complain,
7246 fntype = build_exception_variant (fntype, specs);
7251 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7252 if (domain == error_mark_node)
7253 return error_mark_node;
7255 /* As an optimization, we avoid regenerating the array type if
7256 it will obviously be the same as T. */
7257 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7260 /* These checks should match the ones in grokdeclarator.
7264 The deduction may fail for any of the following reasons:
7266 -- Attempting to create an array with an element type that
7267 is void, a function type, or a reference type, or [DR337]
7268 an abstract class type. */
7269 if (TREE_CODE (type) == VOID_TYPE
7270 || TREE_CODE (type) == FUNCTION_TYPE
7271 || TREE_CODE (type) == REFERENCE_TYPE)
7273 if (complain & tf_error)
7274 error ("creating array of %qT", type);
7275 return error_mark_node;
7277 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7279 if (complain & tf_error)
7280 error ("creating array of %qT, which is an abstract class type",
7282 return error_mark_node;
7285 r = build_cplus_array_type (type, domain);
7292 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7293 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7295 if (e1 == error_mark_node || e2 == error_mark_node)
7296 return error_mark_node;
7298 return fold (build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2));
7304 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7305 if (e == error_mark_node)
7306 return error_mark_node;
7308 return fold (build1 (TREE_CODE (t), TREE_TYPE (t), e));
7313 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7314 in_decl, /*entering_scope=*/1);
7315 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7318 if (ctx == error_mark_node || f == error_mark_node)
7319 return error_mark_node;
7321 if (!IS_AGGR_TYPE (ctx))
7323 if (complain & tf_error)
7324 error ("%qT is not a class, struct, or union type", ctx);
7325 return error_mark_node;
7327 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7329 /* Normally, make_typename_type does not require that the CTX
7330 have complete type in order to allow things like:
7332 template <class T> struct S { typename S<T>::X Y; };
7334 But, such constructs have already been resolved by this
7335 point, so here CTX really should have complete type, unless
7336 it's a partial instantiation. */
7337 ctx = complete_type (ctx);
7338 if (!COMPLETE_TYPE_P (ctx))
7340 if (complain & tf_error)
7341 cxx_incomplete_type_error (NULL_TREE, ctx);
7342 return error_mark_node;
7346 f = make_typename_type (ctx, f,
7347 (complain & tf_error) | tf_keep_type_decl);
7348 if (f == error_mark_node)
7350 if (TREE_CODE (f) == TYPE_DECL)
7352 complain |= tf_ignore_bad_quals;
7356 return cp_build_qualified_type_real
7357 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7360 case UNBOUND_CLASS_TEMPLATE:
7362 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7363 in_decl, /*entering_scope=*/1);
7364 tree name = TYPE_IDENTIFIER (t);
7365 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7367 if (ctx == error_mark_node || name == error_mark_node)
7368 return error_mark_node;
7371 parm_list = tsubst_template_parms (parm_list, args, complain);
7372 return make_unbound_class_template (ctx, name, parm_list, complain);
7382 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7383 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7384 if (e1 == error_mark_node || e2 == error_mark_node)
7385 return error_mark_node;
7387 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7392 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7393 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7394 if (e1 == error_mark_node || e2 == error_mark_node)
7395 return error_mark_node;
7397 return build_nt (TREE_CODE (t), e1, e2);
7404 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7405 complain, in_decl));
7406 return cp_build_qualified_type_real (type,
7408 | cp_type_quals (type),
7413 sorry ("use of %qs in template",
7414 tree_code_name [(int) TREE_CODE (t)]);
7415 return error_mark_node;
7419 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7420 type of the expression on the left-hand side of the "." or "->"
7424 tsubst_baselink (tree baselink, tree object_type,
7425 tree args, tsubst_flags_t complain, tree in_decl)
7428 tree qualifying_scope;
7430 tree template_args = 0;
7431 bool template_id_p = false;
7433 /* A baselink indicates a function from a base class. The
7434 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7435 non-dependent types; otherwise, the lookup could not have
7436 succeeded. However, they may indicate bases of the template
7437 class, rather than the instantiated class.
7439 In addition, lookups that were not ambiguous before may be
7440 ambiguous now. Therefore, we perform the lookup again. */
7441 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7442 fns = BASELINK_FUNCTIONS (baselink);
7443 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7445 template_id_p = true;
7446 template_args = TREE_OPERAND (fns, 1);
7447 fns = TREE_OPERAND (fns, 0);
7449 template_args = tsubst_template_args (template_args, args,
7452 name = DECL_NAME (get_first_fn (fns));
7453 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7455 /* If lookup found a single function, mark it as used at this
7456 point. (If it lookup found multiple functions the one selected
7457 later by overload resolution will be marked as used at that
7459 if (BASELINK_P (baselink))
7460 fns = BASELINK_FUNCTIONS (baselink);
7461 if (!template_id_p && !really_overloaded_fn (fns))
7462 mark_used (OVL_CURRENT (fns));
7464 /* Add back the template arguments, if present. */
7465 if (BASELINK_P (baselink) && template_id_p)
7466 BASELINK_FUNCTIONS (baselink)
7467 = build_nt (TEMPLATE_ID_EXPR,
7468 BASELINK_FUNCTIONS (baselink),
7472 object_type = current_class_type;
7473 return adjust_result_of_qualified_name_lookup (baselink,
7478 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7479 true if the qualified-id will be a postfix-expression in-and-of
7480 itself; false if more of the postfix-expression follows the
7481 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7485 tsubst_qualified_id (tree qualified_id, tree args,
7486 tsubst_flags_t complain, tree in_decl,
7487 bool done, bool address_p)
7495 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7497 /* Figure out what name to look up. */
7498 name = TREE_OPERAND (qualified_id, 1);
7499 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7502 template_args = TREE_OPERAND (name, 1);
7504 template_args = tsubst_template_args (template_args, args,
7506 name = TREE_OPERAND (name, 0);
7510 is_template = false;
7511 template_args = NULL_TREE;
7514 /* Substitute into the qualifying scope. When there are no ARGS, we
7515 are just trying to simplify a non-dependent expression. In that
7516 case the qualifying scope may be dependent, and, in any case,
7517 substituting will not help. */
7518 scope = TREE_OPERAND (qualified_id, 0);
7521 scope = tsubst (scope, args, complain, in_decl);
7522 expr = tsubst_copy (name, args, complain, in_decl);
7527 if (dependent_type_p (scope))
7528 return build_nt (SCOPE_REF, scope, expr);
7530 if (!BASELINK_P (name) && !DECL_P (expr))
7532 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7533 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7534 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7536 if (complain & tf_error)
7538 error ("dependent-name %qE is parsed as a non-type, but "
7539 "instantiation yields a type", qualified_id);
7540 inform ("say %<typename %E%> if a type is meant", qualified_id);
7542 return error_mark_node;
7548 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7550 /* Remember that there was a reference to this entity. */
7554 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7556 if (complain & tf_error)
7557 qualified_name_lookup_error (scope,
7558 TREE_OPERAND (qualified_id, 1),
7560 return error_mark_node;
7564 expr = lookup_template_function (expr, template_args);
7566 if (expr == error_mark_node && complain & tf_error)
7567 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7569 else if (TYPE_P (scope))
7571 expr = (adjust_result_of_qualified_name_lookup
7572 (expr, scope, current_class_type));
7573 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7579 /* Like tsubst, but deals with expressions. This function just replaces
7580 template parms; to finish processing the resultant expression, use
7584 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7586 enum tree_code code;
7589 if (t == NULL_TREE || t == error_mark_node)
7592 code = TREE_CODE (t);
7597 r = retrieve_local_specialization (t);
7598 gcc_assert (r != NULL);
7607 if (DECL_TEMPLATE_PARM_P (t))
7608 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7609 /* There is no need to substitute into namespace-scope
7611 if (DECL_NAMESPACE_SCOPE_P (t))
7613 /* If ARGS is NULL, then T is known to be non-dependent. */
7614 if (args == NULL_TREE)
7615 return decl_constant_value (t);
7617 /* Unfortunately, we cannot just call lookup_name here.
7620 template <int I> int f() {
7622 struct S { void g() { E e = a; } };
7625 When we instantiate f<7>::S::g(), say, lookup_name is not
7626 clever enough to find f<7>::a. */
7628 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7629 /*entering_scope=*/0);
7631 for (v = TYPE_VALUES (enum_type);
7634 if (TREE_PURPOSE (v) == DECL_NAME (t))
7635 return TREE_VALUE (v);
7637 /* We didn't find the name. That should never happen; if
7638 name-lookup found it during preliminary parsing, we
7639 should find it again here during instantiation. */
7645 if (DECL_CONTEXT (t))
7649 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7650 /*entering_scope=*/1);
7651 if (ctx != DECL_CONTEXT (t))
7652 return lookup_field (ctx, DECL_NAME (t), 0, false);
7659 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7660 || local_variable_p (t))
7661 t = tsubst (t, args, complain, in_decl);
7666 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7669 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7670 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7671 args, complain, in_decl);
7672 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7673 return tsubst (t, args, complain, in_decl);
7674 else if (DECL_CLASS_SCOPE_P (t)
7675 && uses_template_parms (DECL_CONTEXT (t)))
7677 /* Template template argument like the following example need
7680 template <template <class> class TT> struct C {};
7681 template <class T> struct D {
7682 template <class U> struct E {};
7687 We are processing the template argument `E' in #1 for
7688 the template instantiation #2. Originally, `E' is a
7689 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7690 have to substitute this with one having context `D<int>'. */
7692 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7693 return lookup_field (context, DECL_NAME(t), 0, false);
7696 /* Ordinary template template argument. */
7700 case REINTERPRET_CAST_EXPR:
7701 case CONST_CAST_EXPR:
7702 case STATIC_CAST_EXPR:
7703 case DYNAMIC_CAST_EXPR:
7706 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7707 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7711 case TRUTH_NOT_EXPR:
7714 case CONVERT_EXPR: /* Unary + */
7723 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7724 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7731 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7732 name = TREE_OPERAND (t, 1);
7733 if (TREE_CODE (name) == BIT_NOT_EXPR)
7735 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7737 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7739 else if (TREE_CODE (name) == SCOPE_REF
7740 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7742 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7744 name = TREE_OPERAND (name, 1);
7745 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7747 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7748 name = build_nt (SCOPE_REF, base, name);
7750 else if (TREE_CODE (name) == BASELINK)
7751 name = tsubst_baselink (name,
7752 non_reference (TREE_TYPE (object)),
7756 name = tsubst_copy (name, args, complain, in_decl);
7757 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7763 case TRUNC_DIV_EXPR:
7765 case FLOOR_DIV_EXPR:
7766 case ROUND_DIV_EXPR:
7767 case EXACT_DIV_EXPR:
7771 case TRUNC_MOD_EXPR:
7772 case FLOOR_MOD_EXPR:
7773 case TRUTH_ANDIF_EXPR:
7774 case TRUTH_ORIF_EXPR:
7775 case TRUTH_AND_EXPR:
7794 case PREDECREMENT_EXPR:
7795 case PREINCREMENT_EXPR:
7796 case POSTDECREMENT_EXPR:
7797 case POSTINCREMENT_EXPR:
7799 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7800 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7803 return build_nt (code,
7804 tsubst_copy (TREE_OPERAND (t, 0), args,
7806 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7812 case PSEUDO_DTOR_EXPR:
7815 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7816 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7817 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7818 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7825 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7826 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7827 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7828 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7835 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7836 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7837 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7838 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7842 case TEMPLATE_ID_EXPR:
7844 /* Substituted template arguments */
7845 tree fn = TREE_OPERAND (t, 0);
7846 tree targs = TREE_OPERAND (t, 1);
7848 fn = tsubst_copy (fn, args, complain, in_decl);
7850 targs = tsubst_template_args (targs, args, complain, in_decl);
7852 return lookup_template_function (fn, targs);
7857 tree purpose, value, chain;
7859 if (t == void_list_node)
7862 purpose = TREE_PURPOSE (t);
7864 purpose = tsubst_copy (purpose, args, complain, in_decl);
7865 value = TREE_VALUE (t);
7867 value = tsubst_copy (value, args, complain, in_decl);
7868 chain = TREE_CHAIN (t);
7869 if (chain && chain != void_type_node)
7870 chain = tsubst_copy (chain, args, complain, in_decl);
7871 if (purpose == TREE_PURPOSE (t)
7872 && value == TREE_VALUE (t)
7873 && chain == TREE_CHAIN (t))
7875 return tree_cons (purpose, value, chain);
7882 case TEMPLATE_TYPE_PARM:
7883 case TEMPLATE_TEMPLATE_PARM:
7884 case BOUND_TEMPLATE_TEMPLATE_PARM:
7885 case TEMPLATE_PARM_INDEX:
7887 case REFERENCE_TYPE:
7893 case UNBOUND_CLASS_TEMPLATE:
7896 return tsubst (t, args, complain, in_decl);
7898 case IDENTIFIER_NODE:
7899 if (IDENTIFIER_TYPENAME_P (t))
7901 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7902 return mangle_conv_op_name_for_type (new_type);
7909 r = build_constructor
7910 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7911 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7912 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7917 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7919 tsubst (TREE_TYPE (t), args, complain, in_decl));
7921 case CLEANUP_POINT_EXPR:
7922 /* We shouldn't have built any of these during initial template
7923 generation. Instead, they should be built during instantiation
7924 in response to the saved STMT_IS_FULL_EXPR_P setting. */
7932 /* Like tsubst_copy for expressions, etc. but also does semantic
7936 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7940 if (t == NULL_TREE || t == error_mark_node)
7943 if (EXPR_HAS_LOCATION (t))
7944 input_location = EXPR_LOCATION (t);
7945 if (STATEMENT_CODE_P (TREE_CODE (t)))
7946 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
7948 switch (TREE_CODE (t))
7950 case STATEMENT_LIST:
7952 tree_stmt_iterator i;
7953 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
7954 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
7958 case CTOR_INITIALIZER:
7959 finish_mem_initializers (tsubst_initializer_list
7960 (TREE_OPERAND (t, 0), args));
7964 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
7965 args, complain, in_decl));
7969 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
7970 if (EXPR_STMT_STMT_EXPR_RESULT (t))
7971 finish_stmt_expr_expr (tmp, cur_stmt_expr);
7973 finish_expr_stmt (tmp);
7977 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
7978 args, complain, in_decl));
7986 decl = DECL_EXPR_DECL (t);
7987 if (TREE_CODE (decl) == LABEL_DECL)
7988 finish_label_decl (DECL_NAME (decl));
7989 else if (TREE_CODE (decl) == USING_DECL)
7991 tree scope = DECL_INITIAL (decl);
7992 tree name = DECL_NAME (decl);
7995 scope = tsubst_expr (scope, args, complain, in_decl);
7996 decl = lookup_qualified_name (scope, name,
7997 /*is_type_p=*/false,
7998 /*complain=*/false);
7999 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8000 qualified_name_lookup_error (scope, name, decl);
8002 do_local_using_decl (decl, scope, name);
8006 init = DECL_INITIAL (decl);
8007 decl = tsubst (decl, args, complain, in_decl);
8008 if (decl != error_mark_node)
8011 DECL_INITIAL (decl) = error_mark_node;
8012 /* By marking the declaration as instantiated, we avoid
8013 trying to instantiate it. Since instantiate_decl can't
8014 handle local variables, and since we've already done
8015 all that needs to be done, that's the right thing to
8017 if (TREE_CODE (decl) == VAR_DECL)
8018 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8019 if (TREE_CODE (decl) == VAR_DECL
8020 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8021 /* Anonymous aggregates are a special case. */
8022 finish_anon_union (decl);
8025 maybe_push_decl (decl);
8026 if (TREE_CODE (decl) == VAR_DECL
8027 && DECL_PRETTY_FUNCTION_P (decl))
8029 /* For __PRETTY_FUNCTION__ we have to adjust the
8031 const char *const name
8032 = cxx_printable_name (current_function_decl, 2);
8033 init = cp_fname_init (name, &TREE_TYPE (decl));
8036 init = tsubst_expr (init, args, complain, in_decl);
8037 cp_finish_decl (decl, init, NULL_TREE, 0);
8042 /* A DECL_EXPR can also be used as an expression, in the condition
8043 clause of an if/for/while construct. */
8048 stmt = begin_for_stmt ();
8049 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8050 finish_for_init_stmt (stmt);
8051 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8052 finish_for_cond (tmp, stmt);
8053 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8054 finish_for_expr (tmp, stmt);
8055 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8056 finish_for_stmt (stmt);
8060 stmt = begin_while_stmt ();
8061 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8062 finish_while_stmt_cond (tmp, stmt);
8063 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8064 finish_while_stmt (stmt);
8068 stmt = begin_do_stmt ();
8069 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8070 finish_do_body (stmt);
8071 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8072 finish_do_stmt (tmp, stmt);
8076 stmt = begin_if_stmt ();
8077 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8078 finish_if_stmt_cond (tmp, stmt);
8079 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8080 finish_then_clause (stmt);
8082 if (ELSE_CLAUSE (t))
8084 begin_else_clause (stmt);
8085 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8086 finish_else_clause (stmt);
8089 finish_if_stmt (stmt);
8093 if (BIND_EXPR_BODY_BLOCK (t))
8094 stmt = begin_function_body ();
8096 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8097 ? BCS_TRY_BLOCK : 0);
8099 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8101 if (BIND_EXPR_BODY_BLOCK (t))
8102 finish_function_body (stmt);
8104 finish_compound_stmt (stmt);
8108 finish_break_stmt ();
8112 finish_continue_stmt ();
8116 stmt = begin_switch_stmt ();
8117 tmp = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
8118 finish_switch_cond (tmp, stmt);
8119 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
8120 finish_switch_stmt (stmt);
8123 case CASE_LABEL_EXPR:
8124 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8125 tsubst_expr (CASE_HIGH (t), args, complain,
8130 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8134 tmp = GOTO_DESTINATION (t);
8135 if (TREE_CODE (tmp) != LABEL_DECL)
8136 /* Computed goto's must be tsubst'd into. On the other hand,
8137 non-computed gotos must not be; the identifier in question
8138 will have no binding. */
8139 tmp = tsubst_expr (tmp, args, complain, in_decl);
8141 tmp = DECL_NAME (tmp);
8142 finish_goto_stmt (tmp);
8146 tmp = finish_asm_stmt
8147 (ASM_VOLATILE_P (t),
8148 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8149 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8150 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8151 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8153 tree asm_expr = tmp;
8154 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8155 asm_expr = TREE_OPERAND (asm_expr, 0);
8156 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8163 stmt = begin_try_block ();
8164 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8165 finish_cleanup_try_block (stmt);
8166 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8172 if (FN_TRY_BLOCK_P (t))
8173 stmt = begin_function_try_block ();
8175 stmt = begin_try_block ();
8177 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8179 if (FN_TRY_BLOCK_P (t))
8180 finish_function_try_block (stmt);
8182 finish_try_block (stmt);
8184 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8185 if (FN_TRY_BLOCK_P (t))
8186 finish_function_handler_sequence (stmt);
8188 finish_handler_sequence (stmt);
8196 stmt = begin_handler ();
8197 if (HANDLER_PARMS (t))
8199 decl = HANDLER_PARMS (t);
8200 decl = tsubst (decl, args, complain, in_decl);
8201 /* Prevent instantiate_decl from trying to instantiate
8202 this variable. We've already done all that needs to be
8204 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8208 finish_handler_parms (decl, stmt);
8209 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8210 finish_handler (stmt);
8215 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8219 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8221 return tsubst_copy_and_build (t, args, complain, in_decl,
8222 /*function_p=*/false);
8228 /* T is a postfix-expression that is not being used in a function
8229 call. Return the substituted version of T. */
8232 tsubst_non_call_postfix_expression (tree t, tree args,
8233 tsubst_flags_t complain,
8236 if (TREE_CODE (t) == SCOPE_REF)
8237 t = tsubst_qualified_id (t, args, complain, in_decl,
8238 /*done=*/false, /*address_p=*/false);
8240 t = tsubst_copy_and_build (t, args, complain, in_decl,
8241 /*function_p=*/false);
8246 /* Like tsubst but deals with expressions and performs semantic
8247 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8250 tsubst_copy_and_build (tree t,
8252 tsubst_flags_t complain,
8256 #define RECUR(NODE) \
8257 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8261 if (t == NULL_TREE || t == error_mark_node)
8264 switch (TREE_CODE (t))
8269 case IDENTIFIER_NODE:
8273 tree qualifying_class;
8274 bool non_integral_constant_expression_p;
8275 const char *error_msg;
8277 if (IDENTIFIER_TYPENAME_P (t))
8279 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8280 t = mangle_conv_op_name_for_type (new_type);
8283 /* Look up the name. */
8284 decl = lookup_name (t, 0);
8286 /* By convention, expressions use ERROR_MARK_NODE to indicate
8287 failure, not NULL_TREE. */
8288 if (decl == NULL_TREE)
8289 decl = error_mark_node;
8291 decl = finish_id_expression (t, decl, NULL_TREE,
8294 /*integral_constant_expression_p=*/false,
8295 /*allow_non_integral_constant_expression_p=*/false,
8296 &non_integral_constant_expression_p,
8300 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8301 decl = unqualified_name_lookup_error (decl);
8305 case TEMPLATE_ID_EXPR:
8308 tree template = RECUR (TREE_OPERAND (t, 0));
8309 tree targs = TREE_OPERAND (t, 1);
8312 targs = tsubst_template_args (targs, args, complain, in_decl);
8314 if (TREE_CODE (template) == COMPONENT_REF)
8316 object = TREE_OPERAND (template, 0);
8317 template = TREE_OPERAND (template, 1);
8321 template = lookup_template_function (template, targs);
8324 return build3 (COMPONENT_REF, TREE_TYPE (template),
8325 object, template, NULL_TREE);
8331 return build_x_indirect_ref (RECUR (TREE_OPERAND (t, 0)), "unary *");
8335 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8336 RECUR (TREE_OPERAND (t, 0)));
8339 return build_functional_cast
8340 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8341 RECUR (TREE_OPERAND (t, 0)));
8343 case REINTERPRET_CAST_EXPR:
8344 return build_reinterpret_cast
8345 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8346 RECUR (TREE_OPERAND (t, 0)));
8348 case CONST_CAST_EXPR:
8349 return build_const_cast
8350 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8351 RECUR (TREE_OPERAND (t, 0)));
8353 case DYNAMIC_CAST_EXPR:
8354 return build_dynamic_cast
8355 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8356 RECUR (TREE_OPERAND (t, 0)));
8358 case STATIC_CAST_EXPR:
8359 return build_static_cast
8360 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8361 RECUR (TREE_OPERAND (t, 0)));
8363 case POSTDECREMENT_EXPR:
8364 case POSTINCREMENT_EXPR:
8365 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8366 args, complain, in_decl);
8367 return build_x_unary_op (TREE_CODE (t), op1);
8369 case PREDECREMENT_EXPR:
8370 case PREINCREMENT_EXPR:
8374 case TRUTH_NOT_EXPR:
8375 case CONVERT_EXPR: /* Unary + */
8378 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8381 op1 = TREE_OPERAND (t, 0);
8382 if (TREE_CODE (op1) == SCOPE_REF)
8383 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8384 /*done=*/true, /*address_p=*/true);
8386 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8388 if (TREE_CODE (op1) == LABEL_DECL)
8389 return finish_label_address_expr (DECL_NAME (op1));
8390 return build_x_unary_op (ADDR_EXPR, op1);
8395 case TRUNC_DIV_EXPR:
8397 case FLOOR_DIV_EXPR:
8398 case ROUND_DIV_EXPR:
8399 case EXACT_DIV_EXPR:
8403 case TRUNC_MOD_EXPR:
8404 case FLOOR_MOD_EXPR:
8405 case TRUTH_ANDIF_EXPR:
8406 case TRUTH_ORIF_EXPR:
8407 case TRUTH_AND_EXPR:
8423 return build_x_binary_op
8425 RECUR (TREE_OPERAND (t, 0)),
8426 RECUR (TREE_OPERAND (t, 1)),
8427 /*overloaded_p=*/NULL);
8430 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8431 /*address_p=*/false);
8434 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8437 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)),
8438 NULL_TREE, NULL_TREE);
8440 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8441 args, complain, in_decl);
8442 /* Remember that there was a reference to this entity. */
8445 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8449 op1 = TREE_OPERAND (t, 0);
8452 /* When there are no ARGS, we are trying to evaluate a
8453 non-dependent expression from the parser. Trying to do
8454 the substitutions may not work. */
8456 op1 = TREE_TYPE (op1);
8465 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8467 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8471 tree r = build_x_modify_expr
8472 (RECUR (TREE_OPERAND (t, 0)),
8473 TREE_CODE (TREE_OPERAND (t, 1)),
8474 RECUR (TREE_OPERAND (t, 2)));
8475 /* TREE_NO_WARNING must be set if either the expression was
8476 parenthesized or it uses an operator such as >>= rather
8477 than plain assignment. In the former case, it was already
8478 set and must be copied. In the latter case,
8479 build_x_modify_expr sets it and it must not be reset
8481 if (TREE_NO_WARNING (t))
8482 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8487 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8488 args, complain, in_decl);
8489 /* Remember that there was a reference to this entity. */
8492 return build_x_arrow (op1);
8496 (RECUR (TREE_OPERAND (t, 0)),
8497 RECUR (TREE_OPERAND (t, 1)),
8498 RECUR (TREE_OPERAND (t, 2)),
8499 RECUR (TREE_OPERAND (t, 3)),
8500 NEW_EXPR_USE_GLOBAL (t));
8503 return delete_sanity
8504 (RECUR (TREE_OPERAND (t, 0)),
8505 RECUR (TREE_OPERAND (t, 1)),
8506 DELETE_EXPR_USE_VEC (t),
8507 DELETE_EXPR_USE_GLOBAL (t));
8510 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8511 RECUR (TREE_OPERAND (t, 1)));
8520 function = TREE_OPERAND (t, 0);
8521 /* When we parsed the expression, we determined whether or
8522 not Koenig lookup should be performed. */
8523 koenig_p = KOENIG_LOOKUP_P (t);
8524 if (TREE_CODE (function) == SCOPE_REF)
8527 function = tsubst_qualified_id (function, args, complain, in_decl,
8529 /*address_p=*/false);
8533 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8534 && (TREE_CODE (TREE_OPERAND (function, 1))
8536 function = tsubst_copy_and_build (function, args, complain,
8539 if (BASELINK_P (function))
8543 call_args = RECUR (TREE_OPERAND (t, 1));
8545 /* We do not perform argument-dependent lookup if normal
8546 lookup finds a non-function, in accordance with the
8547 expected resolution of DR 218. */
8549 && ((is_overloaded_fn (function)
8550 /* If lookup found a member function, the Koenig lookup is
8551 not appropriate, even if an unqualified-name was used
8552 to denote the function. */
8553 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8554 || TREE_CODE (function) == IDENTIFIER_NODE))
8555 function = perform_koenig_lookup (function, call_args);
8557 if (TREE_CODE (function) == IDENTIFIER_NODE)
8559 unqualified_name_lookup_error (function);
8560 return error_mark_node;
8563 /* Remember that there was a reference to this entity. */
8564 if (DECL_P (function))
8565 mark_used (function);
8567 function = convert_from_reference (function);
8569 if (TREE_CODE (function) == OFFSET_REF)
8570 return build_offset_ref_call_from_tree (function, call_args);
8571 if (TREE_CODE (function) == COMPONENT_REF)
8573 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8574 return finish_call_expr (function, call_args,
8575 /*disallow_virtual=*/false,
8576 /*koenig_p=*/false);
8578 return (build_new_method_call
8579 (TREE_OPERAND (function, 0),
8580 TREE_OPERAND (function, 1),
8581 call_args, NULL_TREE,
8582 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8584 return finish_call_expr (function, call_args,
8585 /*disallow_virtual=*/qualified_p,
8590 return build_x_conditional_expr
8591 (RECUR (TREE_OPERAND (t, 0)),
8592 RECUR (TREE_OPERAND (t, 1)),
8593 RECUR (TREE_OPERAND (t, 2)));
8595 case PSEUDO_DTOR_EXPR:
8596 return finish_pseudo_destructor_expr
8597 (RECUR (TREE_OPERAND (t, 0)),
8598 RECUR (TREE_OPERAND (t, 1)),
8599 RECUR (TREE_OPERAND (t, 2)));
8603 tree purpose, value, chain;
8605 if (t == void_list_node)
8608 purpose = TREE_PURPOSE (t);
8610 purpose = RECUR (purpose);
8611 value = TREE_VALUE (t);
8613 value = RECUR (value);
8614 chain = TREE_CHAIN (t);
8615 if (chain && chain != void_type_node)
8616 chain = RECUR (chain);
8617 if (purpose == TREE_PURPOSE (t)
8618 && value == TREE_VALUE (t)
8619 && chain == TREE_CHAIN (t))
8621 return tree_cons (purpose, value, chain);
8629 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8630 args, complain, in_decl);
8631 /* Remember that there was a reference to this entity. */
8632 if (DECL_P (object))
8635 member = TREE_OPERAND (t, 1);
8636 if (BASELINK_P (member))
8637 member = tsubst_baselink (member,
8638 non_reference (TREE_TYPE (object)),
8639 args, complain, in_decl);
8641 member = tsubst_copy (member, args, complain, in_decl);
8643 if (!CLASS_TYPE_P (TREE_TYPE (object)))
8645 if (TREE_CODE (member) == BIT_NOT_EXPR)
8646 return finish_pseudo_destructor_expr (object,
8648 TREE_TYPE (object));
8649 else if (TREE_CODE (member) == SCOPE_REF
8650 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8651 return finish_pseudo_destructor_expr (object,
8653 TREE_TYPE (object));
8655 else if (TREE_CODE (member) == SCOPE_REF
8656 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8661 /* Lookup the template functions now that we know what the
8663 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8664 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8665 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8666 /*is_type_p=*/false,
8667 /*complain=*/false);
8668 if (BASELINK_P (member))
8670 BASELINK_FUNCTIONS (member)
8671 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8673 member = (adjust_result_of_qualified_name_lookup
8674 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8675 TREE_TYPE (object)));
8679 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8681 return error_mark_node;
8684 else if (TREE_CODE (member) == SCOPE_REF
8685 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8686 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8688 if (complain & tf_error)
8690 if (TYPE_P (TREE_OPERAND (member, 0)))
8691 error ("%qT is not a class or namespace",
8692 TREE_OPERAND (member, 0));
8694 error ("%qD is not a class or namespace",
8695 TREE_OPERAND (member, 0));
8697 return error_mark_node;
8699 else if (TREE_CODE (member) == FIELD_DECL)
8700 return finish_non_static_data_member (member, object, NULL_TREE);
8702 return finish_class_member_access_expr (object, member);
8707 (RECUR (TREE_OPERAND (t, 0)));
8713 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8716 /* digest_init will do the wrong thing if we let it. */
8717 if (type && TYPE_PTRMEMFUNC_P (type))
8721 /* We do not want to process the purpose of aggregate
8722 initializers as they are identifier nodes which will be
8723 looked up by digest_init. */
8724 purpose_p = !(type && IS_AGGR_TYPE (type));
8725 for (elts = CONSTRUCTOR_ELTS (t);
8727 elts = TREE_CHAIN (elts))
8729 tree purpose = TREE_PURPOSE (elts);
8730 tree value = TREE_VALUE (elts);
8732 if (purpose && purpose_p)
8733 purpose = RECUR (purpose);
8734 value = RECUR (value);
8735 r = tree_cons (purpose, value, r);
8738 r = build_constructor (NULL_TREE, nreverse (r));
8739 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8742 return digest_init (type, r, 0);
8748 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8749 if (TYPE_P (operand_0))
8750 return get_typeid (operand_0);
8751 return build_typeid (operand_0);
8755 return convert_from_reference (tsubst_copy (t, args, complain, in_decl));
8759 t = tsubst_copy (t, args, complain, in_decl);
8760 return convert_from_reference (t);
8763 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8764 tsubst_copy (TREE_TYPE (t), args, complain,
8768 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8772 tree old_stmt_expr = cur_stmt_expr;
8773 tree stmt_expr = begin_stmt_expr ();
8775 cur_stmt_expr = stmt_expr;
8776 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8777 stmt_expr = finish_stmt_expr (stmt_expr, false);
8778 cur_stmt_expr = old_stmt_expr;
8784 t = tsubst_copy (t, args, complain, in_decl);
8785 /* As in finish_id_expression, we resolve enumeration constants
8786 to their underlying values. */
8787 if (TREE_CODE (t) == CONST_DECL)
8788 return DECL_INITIAL (t);
8792 return tsubst_copy (t, args, complain, in_decl);
8798 /* Verify that the instantiated ARGS are valid. For type arguments,
8799 make sure that the type's linkage is ok. For non-type arguments,
8800 make sure they are constants if they are integral or enumerations.
8801 Emit an error under control of COMPLAIN, and return TRUE on error. */
8804 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8806 int ix, len = DECL_NTPARMS (tmpl);
8807 bool result = false;
8809 for (ix = 0; ix != len; ix++)
8811 tree t = TREE_VEC_ELT (args, ix);
8815 /* [basic.link]: A name with no linkage (notably, the name
8816 of a class or enumeration declared in a local scope)
8817 shall not be used to declare an entity with linkage.
8818 This implies that names with no linkage cannot be used as
8819 template arguments. */
8820 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8824 if (!(complain & tf_error))
8826 else if (TYPE_ANONYMOUS_P (nt))
8827 error ("%qT uses anonymous type", t);
8829 error ("%qT uses local type %qT", t, nt);
8832 /* In order to avoid all sorts of complications, we do not
8833 allow variably-modified types as template arguments. */
8834 else if (variably_modified_type_p (t, NULL_TREE))
8836 if (complain & tf_error)
8837 error ("%qT is a variably modified type", t);
8841 /* A non-type argument of integral or enumerated type must be a
8843 else if (TREE_TYPE (t)
8844 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8845 && !TREE_CONSTANT (t))
8847 if (complain & tf_error)
8848 error ("integral expression %qE is not constant", t);
8852 if (result && complain & tf_error)
8853 error (" trying to instantiate %qD", tmpl);
8857 /* Instantiate the indicated variable or function template TMPL with
8858 the template arguments in TARG_PTR. */
8861 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8867 if (tmpl == error_mark_node)
8868 return error_mark_node;
8870 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
8872 /* If this function is a clone, handle it specially. */
8873 if (DECL_CLONED_FUNCTION_P (tmpl))
8878 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8880 if (spec == error_mark_node)
8881 return error_mark_node;
8883 /* Look for the clone. */
8884 FOR_EACH_CLONE (clone, spec)
8885 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8887 /* We should always have found the clone by now. */
8892 /* Check to see if we already have this specialization. */
8893 spec = retrieve_specialization (tmpl, targ_ptr,
8894 /*class_specializations_p=*/false);
8895 if (spec != NULL_TREE)
8898 gen_tmpl = most_general_template (tmpl);
8899 if (tmpl != gen_tmpl)
8901 /* The TMPL is a partial instantiation. To get a full set of
8902 arguments we must add the arguments used to perform the
8903 partial instantiation. */
8904 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
8907 /* Check to see if we already have this specialization. */
8908 spec = retrieve_specialization (gen_tmpl, targ_ptr,
8909 /*class_specializations_p=*/false);
8910 if (spec != NULL_TREE)
8914 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
8916 return error_mark_node;
8918 /* We are building a FUNCTION_DECL, during which the access of its
8919 parameters and return types have to be checked. However this
8920 FUNCTION_DECL which is the desired context for access checking
8921 is not built yet. We solve this chicken-and-egg problem by
8922 deferring all checks until we have the FUNCTION_DECL. */
8923 push_deferring_access_checks (dk_deferred);
8925 /* Substitute template parameters. */
8926 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
8927 targ_ptr, complain, gen_tmpl);
8929 /* Now we know the specialization, compute access previously
8931 push_access_scope (fndecl);
8932 perform_deferred_access_checks ();
8933 pop_access_scope (fndecl);
8934 pop_deferring_access_checks ();
8936 /* The DECL_TI_TEMPLATE should always be the immediate parent
8937 template, not the most general template. */
8938 DECL_TI_TEMPLATE (fndecl) = tmpl;
8940 /* If we've just instantiated the main entry point for a function,
8941 instantiate all the alternate entry points as well. We do this
8942 by cloning the instantiation of the main entry point, not by
8943 instantiating the template clones. */
8944 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
8945 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
8950 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8951 arguments that are being used when calling it. TARGS is a vector
8952 into which the deduced template arguments are placed.
8954 Return zero for success, 2 for an incomplete match that doesn't resolve
8955 all the types, and 1 for complete failure. An error message will be
8956 printed only for an incomplete match.
8958 If FN is a conversion operator, or we are trying to produce a specific
8959 specialization, RETURN_TYPE is the return type desired.
8961 The EXPLICIT_TARGS are explicit template arguments provided via a
8964 The parameter STRICT is one of:
8967 We are deducing arguments for a function call, as in
8971 We are deducing arguments for a conversion function, as in
8975 We are deducing arguments when doing an explicit instantiation
8976 as in [temp.explicit], when determining an explicit specialization
8977 as in [temp.expl.spec], or when taking the address of a function
8978 template, as in [temp.deduct.funcaddr].
8981 We are deducing arguments when calculating the partial
8982 ordering between specializations of function or class
8983 templates, as in [temp.func.order] and [temp.class.order].
8985 LEN is the number of parms to consider before returning success, or -1
8986 for all. This is used in partial ordering to avoid comparing parms for
8987 which no actual argument was passed, since they are not considered in
8988 overload resolution (and are explicitly excluded from consideration in
8989 partial ordering in [temp.func.order]/6). */
8992 fn_type_unification (tree fn,
8993 tree explicit_targs,
8997 unification_kind_t strict,
9004 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9006 fntype = TREE_TYPE (fn);
9011 The specified template arguments must match the template
9012 parameters in kind (i.e., type, nontype, template), and there
9013 must not be more arguments than there are parameters;
9014 otherwise type deduction fails.
9016 Nontype arguments must match the types of the corresponding
9017 nontype template parameters, or must be convertible to the
9018 types of the corresponding nontype parameters as specified in
9019 _temp.arg.nontype_, otherwise type deduction fails.
9021 All references in the function type of the function template
9022 to the corresponding template parameters are replaced by the
9023 specified template argument values. If a substitution in a
9024 template parameter or in the function type of the function
9025 template results in an invalid type, type deduction fails. */
9027 tree converted_args;
9031 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9032 explicit_targs, NULL_TREE, tf_none,
9033 /*require_all_arguments=*/0));
9034 if (converted_args == error_mark_node)
9037 /* Substitute the explicit args into the function type. This is
9038 necessary so that, for instance, explicitly declared function
9039 arguments can match null pointed constants. If we were given
9040 an incomplete set of explicit args, we must not do semantic
9041 processing during substitution as we could create partial
9043 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9044 processing_template_decl += incomplete;
9045 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9046 processing_template_decl -= incomplete;
9048 if (fntype == error_mark_node)
9051 /* Place the explicitly specified arguments in TARGS. */
9052 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9053 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9056 parms = TYPE_ARG_TYPES (fntype);
9057 /* Never do unification on the 'this' parameter. */
9058 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9059 parms = TREE_CHAIN (parms);
9063 /* We've been given a return type to match, prepend it. */
9064 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9065 args = tree_cons (NULL_TREE, return_type, args);
9070 /* We allow incomplete unification without an error message here
9071 because the standard doesn't seem to explicitly prohibit it. Our
9072 callers must be ready to deal with unification failures in any
9074 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9075 targs, parms, args, /*subr=*/0,
9076 strict, /*allow_incomplete*/1, len);
9079 /* All is well so far. Now, check:
9083 When all template arguments have been deduced, all uses of
9084 template parameters in nondeduced contexts are replaced with
9085 the corresponding deduced argument values. If the
9086 substitution results in an invalid type, as described above,
9087 type deduction fails. */
9088 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9095 /* Adjust types before performing type deduction, as described in
9096 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9097 sections are symmetric. PARM is the type of a function parameter
9098 or the return type of the conversion function. ARG is the type of
9099 the argument passed to the call, or the type of the value
9100 initialized with the result of the conversion function. */
9103 maybe_adjust_types_for_deduction (unification_kind_t strict,
9116 /* Swap PARM and ARG throughout the remainder of this
9117 function; the handling is precisely symmetric since PARM
9118 will initialize ARG rather than vice versa. */
9126 /* There is nothing to do in this case. */
9130 /* DR 214. [temp.func.order] is underspecified, and leads to no
9131 ordering between things like `T *' and `T const &' for `U *'.
9132 The former has T=U and the latter T=U*. The former looks more
9133 specialized and John Spicer considers it well-formed (the EDG
9134 compiler accepts it).
9136 John also confirms that deduction should proceed as in a function
9137 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
9138 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
9139 to an actual call can have such a type.
9141 If both ARG and PARM are REFERENCE_TYPE, we change neither.
9142 If only ARG is a REFERENCE_TYPE, we look through that and then
9143 proceed as with DEDUCE_CALL (which could further convert it). */
9144 if (TREE_CODE (*arg) == REFERENCE_TYPE)
9146 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9148 *arg = TREE_TYPE (*arg);
9155 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9157 /* [temp.deduct.call]
9159 If P is not a reference type:
9161 --If A is an array type, the pointer type produced by the
9162 array-to-pointer standard conversion (_conv.array_) is
9163 used in place of A for type deduction; otherwise,
9165 --If A is a function type, the pointer type produced by
9166 the function-to-pointer standard conversion
9167 (_conv.func_) is used in place of A for type deduction;
9170 --If A is a cv-qualified type, the top level
9171 cv-qualifiers of A's type are ignored for type
9173 if (TREE_CODE (*arg) == ARRAY_TYPE)
9174 *arg = build_pointer_type (TREE_TYPE (*arg));
9175 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9176 *arg = build_pointer_type (*arg);
9178 *arg = TYPE_MAIN_VARIANT (*arg);
9181 /* [temp.deduct.call]
9183 If P is a cv-qualified type, the top level cv-qualifiers
9184 of P's type are ignored for type deduction. If P is a
9185 reference type, the type referred to by P is used for
9187 *parm = TYPE_MAIN_VARIANT (*parm);
9188 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9190 *parm = TREE_TYPE (*parm);
9191 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9194 /* DR 322. For conversion deduction, remove a reference type on parm
9195 too (which has been swapped into ARG). */
9196 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9197 *arg = TREE_TYPE (*arg);
9202 /* Most parms like fn_type_unification.
9204 If SUBR is 1, we're being called recursively (to unify the
9205 arguments of a function or method parameter of a function
9209 type_unification_real (tree tparms,
9214 unification_kind_t strict,
9215 int allow_incomplete,
9220 int ntparms = TREE_VEC_LENGTH (tparms);
9222 int saw_undeduced = 0;
9226 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9227 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9228 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9229 gcc_assert (ntparms > 0);
9234 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9235 | UNIFY_ALLOW_DERIVED);
9239 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9243 sub_strict = UNIFY_ALLOW_NONE;
9247 sub_strict = UNIFY_ALLOW_NONE;
9263 && parms != void_list_node
9265 && args != void_list_node)
9267 parm = TREE_VALUE (parms);
9268 parms = TREE_CHAIN (parms);
9269 arg = TREE_VALUE (args);
9270 args = TREE_CHAIN (args);
9272 if (arg == error_mark_node)
9274 if (arg == unknown_type_node)
9275 /* We can't deduce anything from this, but we might get all the
9276 template args from other function args. */
9279 /* Conversions will be performed on a function argument that
9280 corresponds with a function parameter that contains only
9281 non-deducible template parameters and explicitly specified
9282 template parameters. */
9283 if (!uses_template_parms (parm))
9288 type = TREE_TYPE (arg);
9292 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
9294 if (same_type_p (parm, type))
9298 /* It might work; we shouldn't check now, because we might
9299 get into infinite recursion. Overload resolution will
9308 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9309 if (type_unknown_p (arg))
9311 /* [temp.deduct.type] A template-argument can be deduced from
9312 a pointer to function or pointer to member function
9313 argument if the set of overloaded functions does not
9314 contain function templates and at most one of a set of
9315 overloaded functions provides a unique match. */
9317 if (resolve_overloaded_unification
9318 (tparms, targs, parm, arg, strict, sub_strict)
9323 arg = TREE_TYPE (arg);
9324 if (arg == error_mark_node)
9329 int arg_strict = sub_strict;
9332 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9334 if (unify (tparms, targs, parm, arg, arg_strict))
9338 /* Are we done with the interesting parms? */
9342 /* Fail if we've reached the end of the parm list, and more args
9343 are present, and the parm list isn't variadic. */
9344 if (args && args != void_list_node && parms == void_list_node)
9346 /* Fail if parms are left and they don't have default values. */
9348 && parms != void_list_node
9349 && TREE_PURPOSE (parms) == NULL_TREE)
9354 for (i = 0; i < ntparms; i++)
9355 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
9357 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9359 /* If this is an undeduced nontype parameter that depends on
9360 a type parameter, try another pass; its type may have been
9361 deduced from a later argument than the one from which
9362 this parameter can be deduced. */
9363 if (TREE_CODE (tparm) == PARM_DECL
9364 && uses_template_parms (TREE_TYPE (tparm))
9365 && !saw_undeduced++)
9368 if (!allow_incomplete)
9369 error ("incomplete type unification");
9375 /* Subroutine of type_unification_real. Args are like the variables at the
9376 call site. ARG is an overloaded function (or template-id); we try
9377 deducing template args from each of the overloads, and if only one
9378 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9381 resolve_overloaded_unification (tree tparms,
9385 unification_kind_t strict,
9388 tree tempargs = copy_node (targs);
9392 if (TREE_CODE (arg) == ADDR_EXPR)
9394 arg = TREE_OPERAND (arg, 0);
9400 if (TREE_CODE (arg) == COMPONENT_REF)
9401 /* Handle `&x' where `x' is some static or non-static member
9403 arg = TREE_OPERAND (arg, 1);
9405 if (TREE_CODE (arg) == OFFSET_REF)
9406 arg = TREE_OPERAND (arg, 1);
9408 /* Strip baselink information. */
9409 if (BASELINK_P (arg))
9410 arg = BASELINK_FUNCTIONS (arg);
9412 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9414 /* If we got some explicit template args, we need to plug them into
9415 the affected templates before we try to unify, in case the
9416 explicit args will completely resolve the templates in question. */
9418 tree expl_subargs = TREE_OPERAND (arg, 1);
9419 arg = TREE_OPERAND (arg, 0);
9421 for (; arg; arg = OVL_NEXT (arg))
9423 tree fn = OVL_CURRENT (arg);
9426 if (TREE_CODE (fn) != TEMPLATE_DECL)
9429 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
9433 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9434 good += try_one_overload (tparms, targs, tempargs, parm,
9435 elem, strict, sub_strict, addr_p);
9441 gcc_assert (TREE_CODE (arg) == OVERLOAD
9442 || TREE_CODE (arg) == FUNCTION_DECL);
9444 for (; arg; arg = OVL_NEXT (arg))
9445 good += try_one_overload (tparms, targs, tempargs, parm,
9446 TREE_TYPE (OVL_CURRENT (arg)),
9447 strict, sub_strict, addr_p);
9450 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9451 to function or pointer to member function argument if the set of
9452 overloaded functions does not contain function templates and at most
9453 one of a set of overloaded functions provides a unique match.
9455 So if we found multiple possibilities, we return success but don't
9460 int i = TREE_VEC_LENGTH (targs);
9462 if (TREE_VEC_ELT (tempargs, i))
9463 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9471 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9472 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9473 different overloads deduce different arguments for a given parm.
9474 ADDR_P is true if the expression for which deduction is being
9475 performed was of the form "& fn" rather than simply "fn".
9477 Returns 1 on success. */
9480 try_one_overload (tree tparms,
9485 unification_kind_t strict,
9493 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9494 to function or pointer to member function argument if the set of
9495 overloaded functions does not contain function templates and at most
9496 one of a set of overloaded functions provides a unique match.
9498 So if this is a template, just return success. */
9500 if (uses_template_parms (arg))
9503 if (TREE_CODE (arg) == METHOD_TYPE)
9504 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9506 arg = build_pointer_type (arg);
9508 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9510 /* We don't copy orig_targs for this because if we have already deduced
9511 some template args from previous args, unify would complain when we
9512 try to deduce a template parameter for the same argument, even though
9513 there isn't really a conflict. */
9514 nargs = TREE_VEC_LENGTH (targs);
9515 tempargs = make_tree_vec (nargs);
9517 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9520 /* First make sure we didn't deduce anything that conflicts with
9521 explicitly specified args. */
9522 for (i = nargs; i--; )
9524 tree elt = TREE_VEC_ELT (tempargs, i);
9525 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9527 if (elt == NULL_TREE)
9529 else if (uses_template_parms (elt))
9531 /* Since we're unifying against ourselves, we will fill in template
9532 args used in the function parm list with our own template parms.
9534 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9537 else if (oldelt && ! template_args_equal (oldelt, elt))
9541 for (i = nargs; i--; )
9543 tree elt = TREE_VEC_ELT (tempargs, i);
9546 TREE_VEC_ELT (targs, i) = elt;
9552 /* Verify that nondeduce template argument agrees with the type
9553 obtained from argument deduction. Return nonzero if the
9558 struct A { typedef int X; };
9559 template <class T, class U> struct C {};
9560 template <class T> struct C<T, typename T::X> {};
9562 Then with the instantiation `C<A, int>', we can deduce that
9563 `T' is `A' but unify () does not check whether `typename T::X'
9564 is `int'. This function ensure that they agree.
9566 TARGS, PARMS are the same as the arguments of unify.
9567 ARGS contains template arguments from all levels. */
9570 verify_class_unification (tree targs, tree parms, tree args)
9572 parms = tsubst (parms, add_outermost_template_args (args, targs),
9573 tf_none, NULL_TREE);
9574 if (parms == error_mark_node)
9577 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9580 /* PARM is a template class (perhaps with unbound template
9581 parameters). ARG is a fully instantiated type. If ARG can be
9582 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9583 TARGS are as for unify. */
9586 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9590 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9591 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9592 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9595 /* We need to make a new template argument vector for the call to
9596 unify. If we used TARGS, we'd clutter it up with the result of
9597 the attempted unification, even if this class didn't work out.
9598 We also don't want to commit ourselves to all the unifications
9599 we've already done, since unification is supposed to be done on
9600 an argument-by-argument basis. In other words, consider the
9601 following pathological case:
9603 template <int I, int J, int K>
9606 template <int I, int J>
9607 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9609 template <int I, int J, int K>
9610 void f(S<I, J, K>, S<I, I, I>);
9619 Now, by the time we consider the unification involving `s2', we
9620 already know that we must have `f<0, 0, 0>'. But, even though
9621 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9622 because there are two ways to unify base classes of S<0, 1, 2>
9623 with S<I, I, I>. If we kept the already deduced knowledge, we
9624 would reject the possibility I=1. */
9625 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9627 /* If unification failed, we're done. */
9628 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9629 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9635 /* Given a template type PARM and a class type ARG, find the unique
9636 base type in ARG that is an instance of PARM. We do not examine
9637 ARG itself; only its base-classes. If there is not exactly one
9638 appropriate base class, return NULL_TREE. PARM may be the type of
9639 a partial specialization, as well as a plain template type. Used
9643 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9645 tree rval = NULL_TREE;
9648 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9650 binfo = TYPE_BINFO (complete_type (arg));
9652 /* The type could not be completed. */
9655 /* Walk in inheritance graph order. The search order is not
9656 important, and this avoids multiple walks of virtual bases. */
9657 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9659 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9663 /* If there is more than one satisfactory baseclass, then:
9667 If they yield more than one possible deduced A, the type
9671 if (rval && !same_type_p (r, rval))
9681 /* Returns the level of DECL, which declares a template parameter. */
9684 template_decl_level (tree decl)
9686 switch (TREE_CODE (decl))
9690 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9693 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9701 /* Decide whether ARG can be unified with PARM, considering only the
9702 cv-qualifiers of each type, given STRICT as documented for unify.
9703 Returns nonzero iff the unification is OK on that basis. */
9706 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9708 int arg_quals = cp_type_quals (arg);
9709 int parm_quals = cp_type_quals (parm);
9711 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9712 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9714 /* Although a CVR qualifier is ignored when being applied to a
9715 substituted template parameter ([8.3.2]/1 for example), that
9716 does not apply during deduction [14.8.2.4]/1, (even though
9717 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9718 this). Except when we're allowing additional CV qualifiers
9719 at the outer level [14.8.2.1]/3,1st bullet. */
9720 if ((TREE_CODE (arg) == REFERENCE_TYPE
9721 || TREE_CODE (arg) == FUNCTION_TYPE
9722 || TREE_CODE (arg) == METHOD_TYPE)
9723 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9726 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9727 && (parm_quals & TYPE_QUAL_RESTRICT))
9731 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9732 && (arg_quals & parm_quals) != parm_quals)
9735 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9736 && (parm_quals & arg_quals) != arg_quals)
9742 /* Takes parameters as for type_unification. Returns 0 if the
9743 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9744 bitwise or of the following flags:
9747 Require an exact match between PARM and ARG.
9748 UNIFY_ALLOW_MORE_CV_QUAL:
9749 Allow the deduced ARG to be more cv-qualified (by qualification
9750 conversion) than ARG.
9751 UNIFY_ALLOW_LESS_CV_QUAL:
9752 Allow the deduced ARG to be less cv-qualified than ARG.
9753 UNIFY_ALLOW_DERIVED:
9754 Allow the deduced ARG to be a template base class of ARG,
9755 or a pointer to a template base class of the type pointed to by
9757 UNIFY_ALLOW_INTEGER:
9758 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9759 case for more information.
9760 UNIFY_ALLOW_OUTER_LEVEL:
9761 This is the outermost level of a deduction. Used to determine validity
9762 of qualification conversions. A valid qualification conversion must
9763 have const qualified pointers leading up to the inner type which
9764 requires additional CV quals, except at the outer level, where const
9765 is not required [conv.qual]. It would be normal to set this flag in
9766 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9767 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9768 This is the outermost level of a deduction, and PARM can be more CV
9769 qualified at this point.
9770 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9771 This is the outermost level of a deduction, and PARM can be less CV
9772 qualified at this point. */
9775 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9780 int strict_in = strict;
9782 /* I don't think this will do the right thing with respect to types.
9783 But the only case I've seen it in so far has been array bounds, where
9784 signedness is the only information lost, and I think that will be
9786 while (TREE_CODE (parm) == NOP_EXPR)
9787 parm = TREE_OPERAND (parm, 0);
9789 if (arg == error_mark_node)
9791 if (arg == unknown_type_node)
9792 /* We can't deduce anything from this, but we might get all the
9793 template args from other function args. */
9796 /* If PARM uses template parameters, then we can't bail out here,
9797 even if ARG == PARM, since we won't record unifications for the
9798 template parameters. We might need them if we're trying to
9799 figure out which of two things is more specialized. */
9800 if (arg == parm && !uses_template_parms (parm))
9803 /* Immediately reject some pairs that won't unify because of
9804 cv-qualification mismatches. */
9805 if (TREE_CODE (arg) == TREE_CODE (parm)
9807 /* It is the elements of the array which hold the cv quals of an array
9808 type, and the elements might be template type parms. We'll check
9810 && TREE_CODE (arg) != ARRAY_TYPE
9811 /* We check the cv-qualifiers when unifying with template type
9812 parameters below. We want to allow ARG `const T' to unify with
9813 PARM `T' for example, when computing which of two templates
9814 is more specialized, for example. */
9815 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9816 && !check_cv_quals_for_unify (strict_in, arg, parm))
9819 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9820 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9821 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9822 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9823 strict &= ~UNIFY_ALLOW_DERIVED;
9824 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9825 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9827 switch (TREE_CODE (parm))
9831 case UNBOUND_CLASS_TEMPLATE:
9832 /* In a type which contains a nested-name-specifier, template
9833 argument values cannot be deduced for template parameters used
9834 within the nested-name-specifier. */
9837 case TEMPLATE_TYPE_PARM:
9838 case TEMPLATE_TEMPLATE_PARM:
9839 case BOUND_TEMPLATE_TEMPLATE_PARM:
9840 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9842 if (TEMPLATE_TYPE_LEVEL (parm)
9843 != template_decl_level (tparm))
9844 /* The PARM is not one we're trying to unify. Just check
9845 to see if it matches ARG. */
9846 return (TREE_CODE (arg) == TREE_CODE (parm)
9847 && same_type_p (parm, arg)) ? 0 : 1;
9848 idx = TEMPLATE_TYPE_IDX (parm);
9849 targ = TREE_VEC_ELT (targs, idx);
9850 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9852 /* Check for mixed types and values. */
9853 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9854 && TREE_CODE (tparm) != TYPE_DECL)
9855 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9856 && TREE_CODE (tparm) != TEMPLATE_DECL))
9859 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9861 /* ARG must be constructed from a template class or a template
9862 template parameter. */
9863 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9864 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9868 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9869 tree parmvec = TYPE_TI_ARGS (parm);
9870 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9872 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9875 /* The parameter and argument roles have to be switched here
9876 in order to handle default arguments properly. For example,
9877 template<template <class> class TT> void f(TT<int>)
9878 should be able to accept vector<int> which comes from
9879 template <class T, class Allocator = allocator>
9882 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9886 /* Deduce arguments T, i from TT<T> or TT<i>.
9887 We check each element of PARMVEC and ARGVEC individually
9888 rather than the whole TREE_VEC since they can have
9889 different number of elements. */
9891 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9893 if (unify (tparms, targs,
9894 TREE_VEC_ELT (parmvec, i),
9895 TREE_VEC_ELT (argvec, i),
9900 arg = TYPE_TI_TEMPLATE (arg);
9902 /* Fall through to deduce template name. */
9905 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9906 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9908 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9910 /* Simple cases: Value already set, does match or doesn't. */
9911 if (targ != NULL_TREE && template_args_equal (targ, arg))
9918 /* If PARM is `const T' and ARG is only `int', we don't have
9919 a match unless we are allowing additional qualification.
9920 If ARG is `const int' and PARM is just `T' that's OK;
9921 that binds `const int' to `T'. */
9922 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
9926 /* Consider the case where ARG is `const volatile int' and
9927 PARM is `const T'. Then, T should be `volatile int'. */
9928 arg = cp_build_qualified_type_real
9929 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
9930 if (arg == error_mark_node)
9933 /* Simple cases: Value already set, does match or doesn't. */
9934 if (targ != NULL_TREE && same_type_p (targ, arg))
9939 /* Make sure that ARG is not a variable-sized array. (Note
9940 that were talking about variable-sized arrays (like
9941 `int[n]'), rather than arrays of unknown size (like
9942 `int[]').) We'll get very confused by such a type since
9943 the bound of the array will not be computable in an
9944 instantiation. Besides, such types are not allowed in
9945 ISO C++, so we can do as we please here. */
9946 if (variably_modified_type_p (arg, NULL_TREE))
9950 TREE_VEC_ELT (targs, idx) = arg;
9953 case TEMPLATE_PARM_INDEX:
9954 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9956 if (TEMPLATE_PARM_LEVEL (parm)
9957 != template_decl_level (tparm))
9958 /* The PARM is not one we're trying to unify. Just check
9959 to see if it matches ARG. */
9960 return !(TREE_CODE (arg) == TREE_CODE (parm)
9961 && cp_tree_equal (parm, arg));
9963 idx = TEMPLATE_PARM_IDX (parm);
9964 targ = TREE_VEC_ELT (targs, idx);
9967 return !cp_tree_equal (targ, arg);
9969 /* [temp.deduct.type] If, in the declaration of a function template
9970 with a non-type template-parameter, the non-type
9971 template-parameter is used in an expression in the function
9972 parameter-list and, if the corresponding template-argument is
9973 deduced, the template-argument type shall match the type of the
9974 template-parameter exactly, except that a template-argument
9975 deduced from an array bound may be of any integral type.
9976 The non-type parameter might use already deduced type parameters. */
9977 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
9978 if (!TREE_TYPE (arg))
9979 /* Template-parameter dependent expression. Just accept it for now.
9980 It will later be processed in convert_template_argument. */
9982 else if (same_type_p (TREE_TYPE (arg), tparm))
9984 else if ((strict & UNIFY_ALLOW_INTEGER)
9985 && (TREE_CODE (tparm) == INTEGER_TYPE
9986 || TREE_CODE (tparm) == BOOLEAN_TYPE))
9987 /* Convert the ARG to the type of PARM; the deduced non-type
9988 template argument must exactly match the types of the
9989 corresponding parameter. */
9990 arg = fold (build_nop (TREE_TYPE (parm), arg));
9991 else if (uses_template_parms (tparm))
9992 /* We haven't deduced the type of this parameter yet. Try again
9998 TREE_VEC_ELT (targs, idx) = arg;
10003 /* A pointer-to-member constant can be unified only with
10004 another constant. */
10005 if (TREE_CODE (arg) != PTRMEM_CST)
10008 /* Just unify the class member. It would be useless (and possibly
10009 wrong, depending on the strict flags) to unify also
10010 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10011 arg refer to the same variable, even if through different
10012 classes. For instance:
10014 struct A { int x; };
10017 Unification of &A::x and &B::x must succeed. */
10018 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10019 PTRMEM_CST_MEMBER (arg), strict);
10024 if (TREE_CODE (arg) != POINTER_TYPE)
10027 /* [temp.deduct.call]
10029 A can be another pointer or pointer to member type that can
10030 be converted to the deduced A via a qualification
10031 conversion (_conv.qual_).
10033 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10034 This will allow for additional cv-qualification of the
10035 pointed-to types if appropriate. */
10037 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10038 /* The derived-to-base conversion only persists through one
10039 level of pointers. */
10040 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10042 return unify (tparms, targs, TREE_TYPE (parm),
10043 TREE_TYPE (arg), strict);
10046 case REFERENCE_TYPE:
10047 if (TREE_CODE (arg) != REFERENCE_TYPE)
10049 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10050 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10053 if (TREE_CODE (arg) != ARRAY_TYPE)
10055 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10056 != (TYPE_DOMAIN (arg) == NULL_TREE))
10058 if (TYPE_DOMAIN (parm) != NULL_TREE)
10063 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10064 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10066 /* Our representation of array types uses "N - 1" as the
10067 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10068 not an integer constant. */
10069 if (TREE_CODE (parm_max) == MINUS_EXPR)
10071 arg_max = fold (build2 (PLUS_EXPR,
10074 TREE_OPERAND (parm_max, 1)));
10075 parm_max = TREE_OPERAND (parm_max, 0);
10078 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10081 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10082 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10089 case ENUMERAL_TYPE:
10091 if (TREE_CODE (arg) != TREE_CODE (parm))
10094 /* We have already checked cv-qualification at the top of the
10096 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10099 /* As far as unification is concerned, this wins. Later checks
10100 will invalidate it if necessary. */
10103 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10104 /* Type INTEGER_CST can come from ordinary constant template args. */
10106 while (TREE_CODE (arg) == NOP_EXPR)
10107 arg = TREE_OPERAND (arg, 0);
10109 if (TREE_CODE (arg) != INTEGER_CST)
10111 return !tree_int_cst_equal (parm, arg);
10116 if (TREE_CODE (arg) != TREE_VEC)
10118 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10120 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10121 if (unify (tparms, targs,
10122 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10130 if (TREE_CODE (arg) != TREE_CODE (parm))
10133 if (TYPE_PTRMEMFUNC_P (parm))
10135 if (!TYPE_PTRMEMFUNC_P (arg))
10138 return unify (tparms, targs,
10139 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10140 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10144 if (CLASSTYPE_TEMPLATE_INFO (parm))
10146 tree t = NULL_TREE;
10148 if (strict_in & UNIFY_ALLOW_DERIVED)
10150 /* First, we try to unify the PARM and ARG directly. */
10151 t = try_class_unification (tparms, targs,
10156 /* Fallback to the special case allowed in
10157 [temp.deduct.call]:
10159 If P is a class, and P has the form
10160 template-id, then A can be a derived class of
10161 the deduced A. Likewise, if P is a pointer to
10162 a class of the form template-id, A can be a
10163 pointer to a derived class pointed to by the
10165 t = get_template_base (tparms, targs, parm, arg);
10171 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10172 && (CLASSTYPE_TI_TEMPLATE (parm)
10173 == CLASSTYPE_TI_TEMPLATE (arg)))
10174 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10175 Then, we should unify `int' and `U'. */
10178 /* There's no chance of unification succeeding. */
10181 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10182 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10184 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10189 case FUNCTION_TYPE:
10190 if (TREE_CODE (arg) != TREE_CODE (parm))
10193 if (unify (tparms, targs, TREE_TYPE (parm),
10194 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10196 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10197 TYPE_ARG_TYPES (arg), 1,
10198 DEDUCE_EXACT, 0, -1);
10201 if (TREE_CODE (arg) != OFFSET_TYPE)
10203 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10204 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10206 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10210 if (DECL_TEMPLATE_PARM_P (parm))
10211 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10212 if (arg != decl_constant_value (parm))
10217 case TEMPLATE_DECL:
10218 /* Matched cases are handled by the ARG == PARM test above. */
10222 gcc_assert (EXPR_P (parm));
10224 /* We must be looking at an expression. This can happen with
10228 void foo(S<I>, S<I + 2>);
10230 This is a "nondeduced context":
10234 The nondeduced contexts are:
10236 --A type that is a template-id in which one or more of
10237 the template-arguments is an expression that references
10238 a template-parameter.
10240 In these cases, we assume deduction succeeded, but don't
10241 actually infer any unifications. */
10243 if (!uses_template_parms (parm)
10244 && !template_args_equal (parm, arg))
10251 /* Note that DECL can be defined in this translation unit, if
10255 mark_definable (tree decl)
10258 DECL_NOT_REALLY_EXTERN (decl) = 1;
10259 FOR_EACH_CLONE (clone, decl)
10260 DECL_NOT_REALLY_EXTERN (clone) = 1;
10263 /* Called if RESULT is explicitly instantiated, or is a member of an
10264 explicitly instantiated class. */
10267 mark_decl_instantiated (tree result, int extern_p)
10269 SET_DECL_EXPLICIT_INSTANTIATION (result);
10271 /* If this entity has already been written out, it's too late to
10272 make any modifications. */
10273 if (TREE_ASM_WRITTEN (result))
10276 if (TREE_CODE (result) != FUNCTION_DECL)
10277 /* The TREE_PUBLIC flag for function declarations will have been
10278 set correctly by tsubst. */
10279 TREE_PUBLIC (result) = 1;
10281 /* This might have been set by an earlier implicit instantiation. */
10282 DECL_COMDAT (result) = 0;
10285 DECL_NOT_REALLY_EXTERN (result) = 0;
10288 mark_definable (result);
10289 /* Always make artificials weak. */
10290 if (DECL_ARTIFICIAL (result) && flag_weak)
10291 comdat_linkage (result);
10292 /* For WIN32 we also want to put explicit instantiations in
10293 linkonce sections. */
10294 else if (TREE_PUBLIC (result))
10295 maybe_make_one_only (result);
10298 /* If EXTERN_P, then this function will not be emitted -- unless
10299 followed by an explicit instantiation, at which point its linkage
10300 will be adjusted. If !EXTERN_P, then this function will be
10301 emitted here. In neither circumstance do we want
10302 import_export_decl to adjust the linkage. */
10303 DECL_INTERFACE_KNOWN (result) = 1;
10306 /* Given two function templates PAT1 and PAT2, return:
10308 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
10310 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10311 -1 if PAT2 is more specialized than PAT1.
10312 0 if neither is more specialized.
10314 LEN is passed through to fn_type_unification. */
10317 more_specialized (tree pat1, tree pat2, int deduce, int len)
10322 /* If template argument deduction succeeds, we substitute the
10323 resulting arguments into non-deduced contexts. While doing that,
10324 we must be aware that we may encounter dependent types. */
10325 ++processing_template_decl;
10326 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
10327 NULL_TREE, 0, deduce, len);
10331 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
10332 NULL_TREE, 0, deduce, len);
10335 --processing_template_decl;
10340 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10342 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10343 -1 if PAT2 is more specialized than PAT1.
10344 0 if neither is more specialized.
10346 FULL_ARGS is the full set of template arguments that triggers this
10347 partial ordering. */
10350 more_specialized_class (tree pat1, tree pat2, tree full_args)
10355 /* Just like what happens for functions, if we are ordering between
10356 different class template specializations, we may encounter dependent
10357 types in the arguments, and we need our dependency check functions
10358 to behave correctly. */
10359 ++processing_template_decl;
10360 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10361 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10365 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10366 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10369 --processing_template_decl;
10374 /* Return the template arguments that will produce the function signature
10375 DECL from the function template FN, with the explicit template
10376 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
10377 also match. Return NULL_TREE if no satisfactory arguments could be
10378 found. DEDUCE and LEN are passed through to fn_type_unification. */
10381 get_bindings_real (tree fn,
10383 tree explicit_args,
10388 int ntparms = DECL_NTPARMS (fn);
10389 tree targs = make_tree_vec (ntparms);
10391 tree decl_arg_types;
10394 /* Substitute the explicit template arguments into the type of DECL.
10395 The call to fn_type_unification will handle substitution into the
10397 decl_type = TREE_TYPE (decl);
10398 if (explicit_args && uses_template_parms (decl_type))
10401 tree converted_args;
10403 if (DECL_TEMPLATE_INFO (decl))
10404 tmpl = DECL_TI_TEMPLATE (decl);
10406 /* We can get here for some invalid specializations. */
10410 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10411 explicit_args, NULL_TREE,
10412 tf_none, /*require_all_arguments=*/0));
10413 if (converted_args == error_mark_node)
10416 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10417 if (decl_type == error_mark_node)
10421 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10422 /* Never do unification on the 'this' parameter. */
10423 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10424 decl_arg_types = TREE_CHAIN (decl_arg_types);
10426 i = fn_type_unification (fn, explicit_args, targs,
10428 (check_rettype || DECL_CONV_FN_P (fn)
10429 ? TREE_TYPE (decl_type) : NULL_TREE),
10438 /* For most uses, we want to check the return type. */
10441 get_bindings (tree fn, tree decl, tree explicit_args)
10443 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10446 /* But for resolve_overloaded_unification, we only care about the parameter
10450 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10452 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10455 /* Return the innermost template arguments that, when applied to a
10456 template specialization whose innermost template parameters are
10457 TPARMS, and whose specialization arguments are PARMS, yield the
10460 For example, suppose we have:
10462 template <class T, class U> struct S {};
10463 template <class T> struct S<T*, int> {};
10465 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10466 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10467 int}. The resulting vector will be {double}, indicating that `T'
10468 is bound to `double'. */
10471 get_class_bindings (tree tparms, tree parms, tree args)
10473 int i, ntparms = TREE_VEC_LENGTH (tparms);
10474 tree vec = make_tree_vec (ntparms);
10476 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10480 for (i = 0; i < ntparms; ++i)
10481 if (! TREE_VEC_ELT (vec, i))
10484 if (verify_class_unification (vec, parms, args))
10490 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10491 Pick the most specialized template, and return the corresponding
10492 instantiation, or if there is no corresponding instantiation, the
10493 template itself. If there is no most specialized template,
10494 error_mark_node is returned. If there are no templates at all,
10495 NULL_TREE is returned. */
10498 most_specialized_instantiation (tree instantiations)
10503 if (!instantiations)
10506 champ = instantiations;
10507 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10509 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10517 fn = TREE_CHAIN (fn);
10519 return error_mark_node;
10525 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10527 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10530 return error_mark_node;
10533 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10536 /* Return the most specialized of the list of templates in FNS that can
10537 produce an instantiation matching DECL, given the explicit template
10538 arguments EXPLICIT_ARGS. */
10541 most_specialized (tree fns, tree decl, tree explicit_args)
10543 tree candidates = NULL_TREE;
10546 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10548 tree candidate = TREE_VALUE (fn);
10550 args = get_bindings (candidate, decl, explicit_args);
10552 candidates = tree_cons (NULL_TREE, candidate, candidates);
10555 return most_specialized_instantiation (candidates);
10558 /* If DECL is a specialization of some template, return the most
10559 general such template. Otherwise, returns NULL_TREE.
10561 For example, given:
10563 template <class T> struct S { template <class U> void f(U); };
10565 if TMPL is `template <class U> void S<int>::f(U)' this will return
10566 the full template. This function will not trace past partial
10567 specializations, however. For example, given in addition:
10569 template <class T> struct S<T*> { template <class U> void f(U); };
10571 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10572 `template <class T> template <class U> S<T*>::f(U)'. */
10575 most_general_template (tree decl)
10577 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10578 an immediate specialization. */
10579 if (TREE_CODE (decl) == FUNCTION_DECL)
10581 if (DECL_TEMPLATE_INFO (decl)) {
10582 decl = DECL_TI_TEMPLATE (decl);
10584 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10585 template friend. */
10586 if (TREE_CODE (decl) != TEMPLATE_DECL)
10592 /* Look for more and more general templates. */
10593 while (DECL_TEMPLATE_INFO (decl))
10595 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10596 (See cp-tree.h for details.) */
10597 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10600 if (CLASS_TYPE_P (TREE_TYPE (decl))
10601 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10604 /* Stop if we run into an explicitly specialized class template. */
10605 if (!DECL_NAMESPACE_SCOPE_P (decl)
10606 && DECL_CONTEXT (decl)
10607 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10610 decl = DECL_TI_TEMPLATE (decl);
10616 /* Return the most specialized of the class template specializations
10617 of TMPL which can produce an instantiation matching ARGS, or
10618 error_mark_node if the choice is ambiguous. */
10621 most_specialized_class (tree tmpl, tree args)
10623 tree list = NULL_TREE;
10628 tmpl = most_general_template (tmpl);
10629 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10632 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10635 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10636 TREE_TYPE (list) = TREE_TYPE (t);
10645 t = TREE_CHAIN (t);
10646 for (; t; t = TREE_CHAIN (t))
10648 fate = more_specialized_class (champ, t, args);
10655 t = TREE_CHAIN (t);
10657 return error_mark_node;
10663 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10665 fate = more_specialized_class (champ, t, args);
10667 return error_mark_node;
10673 /* Explicitly instantiate DECL. */
10676 do_decl_instantiation (tree decl, tree storage)
10678 tree result = NULL_TREE;
10682 /* An error occurred, for which grokdeclarator has already issued
10683 an appropriate message. */
10685 else if (! DECL_LANG_SPECIFIC (decl))
10687 error ("explicit instantiation of non-template %q#D", decl);
10690 else if (TREE_CODE (decl) == VAR_DECL)
10692 /* There is an asymmetry here in the way VAR_DECLs and
10693 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10694 the latter, the DECL we get back will be marked as a
10695 template instantiation, and the appropriate
10696 DECL_TEMPLATE_INFO will be set up. This does not happen for
10697 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10698 should handle VAR_DECLs as it currently handles
10700 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10701 if (!result || TREE_CODE (result) != VAR_DECL)
10703 error ("no matching template for %qD found", decl);
10707 else if (TREE_CODE (decl) != FUNCTION_DECL)
10709 error ("explicit instantiation of %q#D", decl);
10715 /* Check for various error cases. Note that if the explicit
10716 instantiation is valid the RESULT will currently be marked as an
10717 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10718 until we get here. */
10720 if (DECL_TEMPLATE_SPECIALIZATION (result))
10722 /* DR 259 [temp.spec].
10724 Both an explicit instantiation and a declaration of an explicit
10725 specialization shall not appear in a program unless the explicit
10726 instantiation follows a declaration of the explicit specialization.
10728 For a given set of template parameters, if an explicit
10729 instantiation of a template appears after a declaration of an
10730 explicit specialization for that template, the explicit
10731 instantiation has no effect. */
10734 else if (DECL_EXPLICIT_INSTANTIATION (result))
10738 No program shall explicitly instantiate any template more
10741 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10742 the first instantiation was `extern' and the second is not,
10743 and EXTERN_P for the opposite case. */
10744 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10745 pedwarn ("duplicate explicit instantiation of %q#D", result);
10746 /* If an "extern" explicit instantiation follows an ordinary
10747 explicit instantiation, the template is instantiated. */
10751 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10753 error ("no matching template for %qD found", result);
10756 else if (!DECL_TEMPLATE_INFO (result))
10758 pedwarn ("explicit instantiation of non-template %q#D", result);
10762 if (storage == NULL_TREE)
10764 else if (storage == ridpointers[(int) RID_EXTERN])
10766 if (pedantic && !in_system_header)
10767 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
10772 error ("storage class %qD applied to template instantiation", storage);
10774 mark_decl_instantiated (result, extern_p);
10776 instantiate_decl (result, /*defer_ok=*/1, /*undefined_ok=*/0);
10780 mark_class_instantiated (tree t, int extern_p)
10782 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10783 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10784 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10785 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10788 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10789 rest_of_type_compilation (t, 1);
10793 /* Called from do_type_instantiation through binding_table_foreach to
10794 do recursive instantiation for the type bound in ENTRY. */
10796 bt_instantiate_type_proc (binding_entry entry, void *data)
10798 tree storage = *(tree *) data;
10800 if (IS_AGGR_TYPE (entry->type)
10801 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10802 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10805 /* Called from do_type_instantiation to instantiate a member
10806 (a member function or a static member variable) of an
10807 explicitly instantiated class template. */
10809 instantiate_class_member (tree decl, int extern_p)
10811 mark_decl_instantiated (decl, extern_p);
10813 instantiate_decl (decl, /*defer_ok=*/1, /* undefined_ok=*/1);
10816 /* Perform an explicit instantiation of template class T. STORAGE, if
10817 non-null, is the RID for extern, inline or static. COMPLAIN is
10818 nonzero if this is called from the parser, zero if called recursively,
10819 since the standard is unclear (as detailed below). */
10822 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10827 int previous_instantiation_extern_p = 0;
10829 if (TREE_CODE (t) == TYPE_DECL)
10832 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10834 error ("explicit instantiation of non-template type %qT", t);
10840 if (!COMPLETE_TYPE_P (t))
10842 if (complain & tf_error)
10843 error ("explicit instantiation of %q#T before definition of template",
10848 if (storage != NULL_TREE)
10850 if (pedantic && !in_system_header)
10851 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
10854 if (storage == ridpointers[(int) RID_INLINE])
10856 else if (storage == ridpointers[(int) RID_EXTERN])
10858 else if (storage == ridpointers[(int) RID_STATIC])
10862 error ("storage class %qD applied to template instantiation",
10868 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10870 /* DR 259 [temp.spec].
10872 Both an explicit instantiation and a declaration of an explicit
10873 specialization shall not appear in a program unless the explicit
10874 instantiation follows a declaration of the explicit specialization.
10876 For a given set of template parameters, if an explicit
10877 instantiation of a template appears after a declaration of an
10878 explicit specialization for that template, the explicit
10879 instantiation has no effect. */
10882 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10886 No program shall explicitly instantiate any template more
10889 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
10890 instantiation was `extern'. If EXTERN_P then the second is.
10891 These cases are OK. */
10892 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
10894 if (!previous_instantiation_extern_p && !extern_p
10895 && (complain & tf_error))
10896 pedwarn ("duplicate explicit instantiation of %q#T", t);
10898 /* If we've already instantiated the template, just return now. */
10899 if (!CLASSTYPE_INTERFACE_ONLY (t))
10903 mark_class_instantiated (t, extern_p);
10911 /* In contrast to implicit instantiation, where only the
10912 declarations, and not the definitions, of members are
10913 instantiated, we have here:
10917 The explicit instantiation of a class template specialization
10918 implies the instantiation of all of its members not
10919 previously explicitly specialized in the translation unit
10920 containing the explicit instantiation.
10922 Of course, we can't instantiate member template classes, since
10923 we don't have any arguments for them. Note that the standard
10924 is unclear on whether the instantiation of the members are
10925 *explicit* instantiations or not. However, the most natural
10926 interpretation is that it should be an explicit instantiation. */
10929 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
10930 if (TREE_CODE (tmp) == FUNCTION_DECL
10931 && DECL_TEMPLATE_INSTANTIATION (tmp))
10932 instantiate_class_member (tmp, extern_p);
10934 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
10935 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
10936 instantiate_class_member (tmp, extern_p);
10938 if (CLASSTYPE_NESTED_UTDS (t))
10939 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
10940 bt_instantiate_type_proc, &storage);
10944 /* Given a function DECL, which is a specialization of TMPL, modify
10945 DECL to be a re-instantiation of TMPL with the same template
10946 arguments. TMPL should be the template into which tsubst'ing
10947 should occur for DECL, not the most general template.
10949 One reason for doing this is a scenario like this:
10952 void f(const T&, int i);
10954 void g() { f(3, 7); }
10957 void f(const T& t, const int i) { }
10959 Note that when the template is first instantiated, with
10960 instantiate_template, the resulting DECL will have no name for the
10961 first parameter, and the wrong type for the second. So, when we go
10962 to instantiate the DECL, we regenerate it. */
10965 regenerate_decl_from_template (tree decl, tree tmpl)
10967 /* The arguments used to instantiate DECL, from the most general
10972 args = DECL_TI_ARGS (decl);
10973 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
10975 /* Make sure that we can see identifiers, and compute access
10977 push_access_scope (decl);
10979 if (TREE_CODE (decl) == FUNCTION_DECL)
10987 args_depth = TMPL_ARGS_DEPTH (args);
10988 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
10989 if (args_depth > parms_depth)
10990 args = get_innermost_template_args (args, parms_depth);
10992 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
10993 args, tf_error, NULL_TREE);
10995 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
10998 /* Merge parameter declarations. */
10999 decl_parm = skip_artificial_parms_for (decl,
11000 DECL_ARGUMENTS (decl));
11002 = skip_artificial_parms_for (code_pattern,
11003 DECL_ARGUMENTS (code_pattern));
11008 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11009 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11010 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11012 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11013 TREE_TYPE (decl_parm) = parm_type;
11014 decl_parm = TREE_CHAIN (decl_parm);
11015 pattern_parm = TREE_CHAIN (pattern_parm);
11018 /* Merge additional specifiers from the CODE_PATTERN. */
11019 if (DECL_DECLARED_INLINE_P (code_pattern)
11020 && !DECL_DECLARED_INLINE_P (decl))
11021 DECL_DECLARED_INLINE_P (decl) = 1;
11022 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11023 DECL_INLINE (decl) = 1;
11025 else if (TREE_CODE (decl) == VAR_DECL)
11027 if (!DECL_INITIALIZED_IN_CLASS_P (decl)
11028 && DECL_INITIAL (code_pattern))
11029 DECL_INITIAL (decl) =
11030 tsubst_expr (DECL_INITIAL (code_pattern), args,
11031 tf_error, DECL_TI_TEMPLATE (decl));
11034 gcc_unreachable ();
11036 pop_access_scope (decl);
11039 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11040 substituted to get DECL. */
11043 template_for_substitution (tree decl)
11045 tree tmpl = DECL_TI_TEMPLATE (decl);
11047 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11048 for the instantiation. This is not always the most general
11049 template. Consider, for example:
11052 struct S { template <class U> void f();
11053 template <> void f<int>(); };
11055 and an instantiation of S<double>::f<int>. We want TD to be the
11056 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11057 while (/* An instantiation cannot have a definition, so we need a
11058 more general template. */
11059 DECL_TEMPLATE_INSTANTIATION (tmpl)
11060 /* We must also deal with friend templates. Given:
11062 template <class T> struct S {
11063 template <class U> friend void f() {};
11066 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11067 so far as the language is concerned, but that's still
11068 where we get the pattern for the instantiation from. On
11069 other hand, if the definition comes outside the class, say:
11071 template <class T> struct S {
11072 template <class U> friend void f();
11074 template <class U> friend void f() {}
11076 we don't need to look any further. That's what the check for
11077 DECL_INITIAL is for. */
11078 || (TREE_CODE (decl) == FUNCTION_DECL
11079 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11080 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11082 /* The present template, TD, should not be a definition. If it
11083 were a definition, we should be using it! Note that we
11084 cannot restructure the loop to just keep going until we find
11085 a template with a definition, since that might go too far if
11086 a specialization was declared, but not defined. */
11087 gcc_assert (TREE_CODE (decl) != VAR_DECL
11088 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11090 /* Fetch the more general template. */
11091 tmpl = DECL_TI_TEMPLATE (tmpl);
11097 /* Produce the definition of D, a _DECL generated from a template. If
11098 DEFER_OK is nonzero, then we don't have to actually do the
11099 instantiation now; we just have to do it sometime. Normally it is
11100 an error if this is an explicit instantiation but D is undefined.
11101 If UNDEFINED_OK is nonzero, then instead we treat it as an implicit
11102 instantiation. UNDEFINED_OK is nonzero only if we are being used
11103 to instantiate the members of an explicitly instantiated class
11108 instantiate_decl (tree d, int defer_ok, int undefined_ok)
11110 tree tmpl = DECL_TI_TEMPLATE (d);
11117 int pattern_defined;
11119 location_t saved_loc = input_location;
11121 /* This function should only be used to instantiate templates for
11122 functions and static member variables. */
11123 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11124 || TREE_CODE (d) == VAR_DECL);
11126 /* Variables are never deferred; if instantiation is required, they
11127 are instantiated right away. That allows for better code in the
11128 case that an expression refers to the value of the variable --
11129 if the variable has a constant value the referring expression can
11130 take advantage of that fact. */
11131 if (TREE_CODE (d) == VAR_DECL)
11134 /* Don't instantiate cloned functions. Instead, instantiate the
11135 functions they cloned. */
11136 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11137 d = DECL_CLONED_FUNCTION (d);
11139 if (DECL_TEMPLATE_INSTANTIATED (d))
11140 /* D has already been instantiated. It might seem reasonable to
11141 check whether or not D is an explicit instantiation, and, if so,
11142 stop here. But when an explicit instantiation is deferred
11143 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11144 is set, even though we still need to do the instantiation. */
11147 /* If we already have a specialization of this declaration, then
11148 there's no reason to instantiate it. Note that
11149 retrieve_specialization gives us both instantiations and
11150 specializations, so we must explicitly check
11151 DECL_TEMPLATE_SPECIALIZATION. */
11152 gen_tmpl = most_general_template (tmpl);
11153 gen_args = DECL_TI_ARGS (d);
11154 spec = retrieve_specialization (gen_tmpl, gen_args,
11155 /*class_specializations_p=*/false);
11156 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11159 /* This needs to happen before any tsubsting. */
11160 if (! push_tinst_level (d))
11163 timevar_push (TV_PARSE);
11165 /* We may be in the middle of deferred access check. Disable it now. */
11166 push_deferring_access_checks (dk_no_deferred);
11168 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11169 for the instantiation. */
11170 td = template_for_substitution (d);
11171 code_pattern = DECL_TEMPLATE_RESULT (td);
11173 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11174 || DECL_TEMPLATE_SPECIALIZATION (td))
11175 /* In the case of a friend template whose definition is provided
11176 outside the class, we may have too many arguments. Drop the
11177 ones we don't need. The same is true for specializations. */
11178 args = get_innermost_template_args
11179 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11183 if (TREE_CODE (d) == FUNCTION_DECL)
11184 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11186 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11187 /* Unless an explicit instantiation directive has already determined
11188 the linkage of D, remember that a definition is available for
11190 if (pattern_defined
11191 && !DECL_INTERFACE_KNOWN (d)
11192 && !DECL_NOT_REALLY_EXTERN (d))
11193 mark_definable (d);
11195 input_location = DECL_SOURCE_LOCATION (d);
11197 if (! pattern_defined && DECL_EXPLICIT_INSTANTIATION (d) && undefined_ok)
11199 DECL_NOT_REALLY_EXTERN (d) = 0;
11200 SET_DECL_IMPLICIT_INSTANTIATION (d);
11205 /* Recheck the substitutions to obtain any warning messages
11206 about ignoring cv qualifiers. */
11207 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11208 tree type = TREE_TYPE (gen);
11210 /* Make sure that we can see identifiers, and compute access
11211 correctly. D is already the target FUNCTION_DECL with the
11213 push_access_scope (d);
11215 if (TREE_CODE (gen) == FUNCTION_DECL)
11217 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11218 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11219 tf_error | tf_warning, d);
11220 /* Don't simply tsubst the function type, as that will give
11221 duplicate warnings about poor parameter qualifications.
11222 The function arguments are the same as the decl_arguments
11223 without the top level cv qualifiers. */
11224 type = TREE_TYPE (type);
11226 tsubst (type, gen_args, tf_error | tf_warning, d);
11228 pop_access_scope (d);
11231 /* We should have set up DECL_INITIAL in instantiate_class_template
11232 for in-class definitions of static data members. */
11233 gcc_assert (!(TREE_CODE (d) == VAR_DECL
11234 && DECL_INITIALIZED_IN_CLASS_P (d)
11235 && DECL_INITIAL (d) == NULL_TREE));
11237 /* Do not instantiate templates that we know will be defined
11239 if (DECL_INTERFACE_KNOWN (d)
11240 && DECL_REALLY_EXTERN (d)
11241 && ! (TREE_CODE (d) == FUNCTION_DECL
11242 && DECL_INLINE (d)))
11244 /* Defer all other templates, unless we have been explicitly
11245 forbidden from doing so. We restore the source position here
11246 because it's used by add_pending_template. */
11247 else if (! pattern_defined || defer_ok)
11249 input_location = saved_loc;
11251 if (at_eof && !pattern_defined
11252 && DECL_EXPLICIT_INSTANTIATION (d))
11255 The definition of a non-exported function template, a
11256 non-exported member function template, or a non-exported
11257 member function or static data member of a class template
11258 shall be present in every translation unit in which it is
11259 explicitly instantiated. */
11261 ("explicit instantiation of %qD but no definition available", d);
11263 add_pending_template (d);
11266 /* Tell the repository that D is available in this translation unit
11267 -- and see if it is supposed to be instantiated here. */
11268 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11270 /* In a PCH file, despite the fact that the repository hasn't
11271 requested instantiation in the PCH it is still possible that
11272 an instantiation will be required in a file that includes the
11275 add_pending_template (d);
11276 /* Instantiate inline functions so that the inliner can do its
11277 job, even though we'll not be emitting a copy of this
11279 if (!(TREE_CODE (d) == FUNCTION_DECL
11280 && flag_inline_trees
11281 && DECL_DECLARED_INLINE_P (d)))
11285 need_push = !cfun || !global_bindings_p ();
11287 push_to_top_level ();
11289 /* Mark D as instantiated so that recursive calls to
11290 instantiate_decl do not try to instantiate it again. */
11291 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11293 /* Regenerate the declaration in case the template has been modified
11294 by a subsequent redeclaration. */
11295 regenerate_decl_from_template (d, td);
11297 /* We already set the file and line above. Reset them now in case
11298 they changed as a result of calling regenerate_decl_from_template. */
11299 input_location = DECL_SOURCE_LOCATION (d);
11301 if (TREE_CODE (d) == VAR_DECL)
11303 /* Clear out DECL_RTL; whatever was there before may not be right
11304 since we've reset the type of the declaration. */
11305 SET_DECL_RTL (d, NULL_RTX);
11306 DECL_IN_AGGR_P (d) = 0;
11308 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11309 initializer. That function will defer actual emission until
11310 we have a chance to determine linkage. */
11311 DECL_EXTERNAL (d) = 0;
11313 /* Enter the scope of D so that access-checking works correctly. */
11314 push_nested_class (DECL_CONTEXT (d));
11316 (!DECL_INITIALIZED_IN_CLASS_P (d)
11317 ? DECL_INITIAL (d) : NULL_TREE),
11319 pop_nested_class ();
11321 else if (TREE_CODE (d) == FUNCTION_DECL)
11323 htab_t saved_local_specializations;
11328 /* Save away the current list, in case we are instantiating one
11329 template from within the body of another. */
11330 saved_local_specializations = local_specializations;
11332 /* Set up the list of local specializations. */
11333 local_specializations = htab_create (37,
11334 hash_local_specialization,
11335 eq_local_specializations,
11338 /* Set up context. */
11339 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11341 /* Create substitution entries for the parameters. */
11342 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11343 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11344 spec_parm = DECL_ARGUMENTS (d);
11345 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11347 register_local_specialization (spec_parm, tmpl_parm);
11348 spec_parm = skip_artificial_parms_for (d, spec_parm);
11349 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11353 register_local_specialization (spec_parm, tmpl_parm);
11354 tmpl_parm = TREE_CHAIN (tmpl_parm);
11355 spec_parm = TREE_CHAIN (spec_parm);
11357 gcc_assert (!spec_parm);
11359 /* Substitute into the body of the function. */
11360 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11361 tf_error | tf_warning, tmpl);
11363 /* We don't need the local specializations any more. */
11364 htab_delete (local_specializations);
11365 local_specializations = saved_local_specializations;
11367 /* Finish the function. */
11368 d = finish_function (0);
11369 expand_or_defer_fn (d);
11372 /* We're not deferring instantiation any more. */
11373 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11376 pop_from_top_level ();
11379 input_location = saved_loc;
11380 pop_deferring_access_checks ();
11381 pop_tinst_level ();
11383 timevar_pop (TV_PARSE);
11388 /* Run through the list of templates that we wish we could
11389 instantiate, and instantiate any we can. RETRIES is the
11390 number of times we retry pending template instantiation. */
11393 instantiate_pending_templates (int retries)
11396 tree last = NULL_TREE;
11398 location_t saved_loc = input_location;
11400 /* Instantiating templates may trigger vtable generation. This in turn
11401 may require further template instantiations. We place a limit here
11402 to avoid infinite loop. */
11403 if (pending_templates && retries >= max_tinst_depth)
11405 cp_error_at ("template instantiation depth exceeds maximum of %d"
11406 " (use -ftemplate-depth-NN to increase the maximum)"
11407 " instantiating %q+D, possibly from virtual table"
11409 max_tinst_depth, TREE_VALUE (pending_templates));
11417 t = &pending_templates;
11420 tree instantiation = TREE_VALUE (*t);
11422 reopen_tinst_level (TREE_PURPOSE (*t));
11424 if (TYPE_P (instantiation))
11428 if (!COMPLETE_TYPE_P (instantiation))
11430 instantiate_class_template (instantiation);
11431 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11432 for (fn = TYPE_METHODS (instantiation);
11434 fn = TREE_CHAIN (fn))
11435 if (! DECL_ARTIFICIAL (fn))
11436 instantiate_decl (fn, /*defer_ok=*/0,
11437 /*undefined_ok=*/0);
11438 if (COMPLETE_TYPE_P (instantiation))
11442 if (COMPLETE_TYPE_P (instantiation))
11443 /* If INSTANTIATION has been instantiated, then we don't
11444 need to consider it again in the future. */
11445 *t = TREE_CHAIN (*t);
11449 t = &TREE_CHAIN (*t);
11454 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11455 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11457 instantiation = instantiate_decl (instantiation,
11459 /*undefined_ok=*/0);
11460 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11464 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11465 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11466 /* If INSTANTIATION has been instantiated, then we don't
11467 need to consider it again in the future. */
11468 *t = TREE_CHAIN (*t);
11472 t = &TREE_CHAIN (*t);
11476 current_tinst_level = NULL_TREE;
11478 last_pending_template = last;
11480 while (reconsider);
11482 input_location = saved_loc;
11485 /* Substitute ARGVEC into T, which is a list of initializers for
11486 either base class or a non-static data member. The TREE_PURPOSEs
11487 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11488 instantiate_decl. */
11491 tsubst_initializer_list (tree t, tree argvec)
11493 tree inits = NULL_TREE;
11495 for (; t; t = TREE_CHAIN (t))
11501 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11503 decl = expand_member_init (decl);
11504 if (decl && !DECL_P (decl))
11505 in_base_initializer = 1;
11507 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11511 else if (TREE_CODE (init) == TREE_LIST)
11512 for (val = init; val; val = TREE_CHAIN (val))
11513 TREE_VALUE (val) = convert_from_reference (TREE_VALUE (val));
11514 else if (init != void_type_node)
11515 init = convert_from_reference (init);
11517 in_base_initializer = 0;
11521 init = build_tree_list (decl, init);
11522 TREE_CHAIN (init) = inits;
11529 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11532 set_current_access_from_decl (tree decl)
11534 if (TREE_PRIVATE (decl))
11535 current_access_specifier = access_private_node;
11536 else if (TREE_PROTECTED (decl))
11537 current_access_specifier = access_protected_node;
11539 current_access_specifier = access_public_node;
11542 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11543 is the instantiation (which should have been created with
11544 start_enum) and ARGS are the template arguments to use. */
11547 tsubst_enum (tree tag, tree newtag, tree args)
11551 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11556 decl = TREE_VALUE (e);
11557 /* Note that in a template enum, the TREE_VALUE is the
11558 CONST_DECL, not the corresponding INTEGER_CST. */
11559 value = tsubst_expr (DECL_INITIAL (decl),
11560 args, tf_error | tf_warning,
11563 /* Give this enumeration constant the correct access. */
11564 set_current_access_from_decl (decl);
11566 /* Actually build the enumerator itself. */
11567 build_enumerator (DECL_NAME (decl), value, newtag);
11570 finish_enum (newtag);
11571 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11572 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11575 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11576 its type -- but without substituting the innermost set of template
11577 arguments. So, innermost set of template parameters will appear in
11581 get_mostly_instantiated_function_type (tree decl)
11589 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11590 targs = DECL_TI_ARGS (decl);
11591 tparms = DECL_TEMPLATE_PARMS (tmpl);
11592 parm_depth = TMPL_PARMS_DEPTH (tparms);
11594 /* There should be as many levels of arguments as there are levels
11596 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11598 fn_type = TREE_TYPE (tmpl);
11600 if (parm_depth == 1)
11601 /* No substitution is necessary. */
11608 /* Replace the innermost level of the TARGS with NULL_TREEs to
11609 let tsubst know not to substitute for those parameters. */
11610 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11611 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11612 SET_TMPL_ARGS_LEVEL (partial_args, i,
11613 TMPL_ARGS_LEVEL (targs, i));
11614 SET_TMPL_ARGS_LEVEL (partial_args,
11615 TMPL_ARGS_DEPTH (targs),
11616 make_tree_vec (DECL_NTPARMS (tmpl)));
11618 /* Make sure that we can see identifiers, and compute access
11619 correctly. We can just use the context of DECL for the
11620 partial substitution here. It depends only on outer template
11621 parameters, regardless of whether the innermost level is
11622 specialized or not. */
11623 push_access_scope (decl);
11625 ++processing_template_decl;
11626 /* Now, do the (partial) substitution to figure out the
11627 appropriate function type. */
11628 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11629 --processing_template_decl;
11631 /* Substitute into the template parameters to obtain the real
11632 innermost set of parameters. This step is important if the
11633 innermost set of template parameters contains value
11634 parameters whose types depend on outer template parameters. */
11635 TREE_VEC_LENGTH (partial_args)--;
11636 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11638 pop_access_scope (decl);
11644 /* Return truthvalue if we're processing a template different from
11645 the last one involved in diagnostics. */
11647 problematic_instantiation_changed (void)
11649 return last_template_error_tick != tinst_level_tick;
11652 /* Remember current template involved in diagnostics. */
11654 record_last_problematic_instantiation (void)
11656 last_template_error_tick = tinst_level_tick;
11660 current_instantiation (void)
11662 return current_tinst_level;
11665 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11666 type. Return zero for ok, nonzero for disallowed. Issue error and
11667 warning messages under control of COMPLAIN. */
11670 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11672 if (INTEGRAL_TYPE_P (type))
11674 else if (POINTER_TYPE_P (type))
11676 else if (TYPE_PTR_TO_MEMBER_P (type))
11678 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11680 else if (TREE_CODE (type) == TYPENAME_TYPE)
11683 if (complain & tf_error)
11684 error ("%q#T is not a valid type for a template constant parameter", type);
11688 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11689 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11692 dependent_type_p_r (tree type)
11698 A type is dependent if it is:
11700 -- a template parameter. Template template parameters are types
11701 for us (since TYPE_P holds true for them) so we handle
11703 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11704 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11706 /* -- a qualified-id with a nested-name-specifier which contains a
11707 class-name that names a dependent type or whose unqualified-id
11708 names a dependent type. */
11709 if (TREE_CODE (type) == TYPENAME_TYPE)
11711 /* -- a cv-qualified type where the cv-unqualified type is
11713 type = TYPE_MAIN_VARIANT (type);
11714 /* -- a compound type constructed from any dependent type. */
11715 if (TYPE_PTR_TO_MEMBER_P (type))
11716 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11717 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11719 else if (TREE_CODE (type) == POINTER_TYPE
11720 || TREE_CODE (type) == REFERENCE_TYPE)
11721 return dependent_type_p (TREE_TYPE (type));
11722 else if (TREE_CODE (type) == FUNCTION_TYPE
11723 || TREE_CODE (type) == METHOD_TYPE)
11727 if (dependent_type_p (TREE_TYPE (type)))
11729 for (arg_type = TYPE_ARG_TYPES (type);
11731 arg_type = TREE_CHAIN (arg_type))
11732 if (dependent_type_p (TREE_VALUE (arg_type)))
11736 /* -- an array type constructed from any dependent type or whose
11737 size is specified by a constant expression that is
11738 value-dependent. */
11739 if (TREE_CODE (type) == ARRAY_TYPE)
11741 if (TYPE_DOMAIN (type)
11742 && ((value_dependent_expression_p
11743 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11744 || (type_dependent_expression_p
11745 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11747 return dependent_type_p (TREE_TYPE (type));
11750 /* -- a template-id in which either the template name is a template
11752 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11754 /* ... or any of the template arguments is a dependent type or
11755 an expression that is type-dependent or value-dependent. */
11756 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11757 && (any_dependent_template_arguments_p
11758 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11761 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11762 expression is not type-dependent, then it should already been
11764 if (TREE_CODE (type) == TYPEOF_TYPE)
11767 /* The standard does not specifically mention types that are local
11768 to template functions or local classes, but they should be
11769 considered dependent too. For example:
11771 template <int I> void f() {
11776 The size of `E' cannot be known until the value of `I' has been
11777 determined. Therefore, `E' must be considered dependent. */
11778 scope = TYPE_CONTEXT (type);
11779 if (scope && TYPE_P (scope))
11780 return dependent_type_p (scope);
11781 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11782 return type_dependent_expression_p (scope);
11784 /* Other types are non-dependent. */
11788 /* Returns TRUE if TYPE is dependent, in the sense of
11789 [temp.dep.type]. */
11792 dependent_type_p (tree type)
11794 /* If there are no template parameters in scope, then there can't be
11795 any dependent types. */
11796 if (!processing_template_decl)
11799 /* If the type is NULL, we have not computed a type for the entity
11800 in question; in that case, the type is dependent. */
11804 /* Erroneous types can be considered non-dependent. */
11805 if (type == error_mark_node)
11808 /* If we have not already computed the appropriate value for TYPE,
11810 if (!TYPE_DEPENDENT_P_VALID (type))
11812 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11813 TYPE_DEPENDENT_P_VALID (type) = 1;
11816 return TYPE_DEPENDENT_P (type);
11819 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11822 dependent_scope_ref_p (tree expression, bool criterion (tree))
11827 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
11829 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11832 scope = TREE_OPERAND (expression, 0);
11833 name = TREE_OPERAND (expression, 1);
11837 An id-expression is type-dependent if it contains a
11838 nested-name-specifier that contains a class-name that names a
11840 /* The suggested resolution to Core Issue 2 implies that if the
11841 qualifying type is the current class, then we must peek
11844 && currently_open_class (scope)
11845 && !criterion (name))
11847 if (dependent_type_p (scope))
11853 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11854 [temp.dep.constexpr] */
11857 value_dependent_expression_p (tree expression)
11859 if (!processing_template_decl)
11862 /* A name declared with a dependent type. */
11863 if (TREE_CODE (expression) == IDENTIFIER_NODE
11864 || (DECL_P (expression)
11865 && type_dependent_expression_p (expression)))
11867 /* A non-type template parameter. */
11868 if ((TREE_CODE (expression) == CONST_DECL
11869 && DECL_TEMPLATE_PARM_P (expression))
11870 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11872 /* A constant with integral or enumeration type and is initialized
11873 with an expression that is value-dependent. */
11874 if (TREE_CODE (expression) == VAR_DECL
11875 && DECL_INITIAL (expression)
11876 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11877 && value_dependent_expression_p (DECL_INITIAL (expression)))
11879 /* These expressions are value-dependent if the type to which the
11880 cast occurs is dependent or the expression being casted is
11881 value-dependent. */
11882 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11883 || TREE_CODE (expression) == STATIC_CAST_EXPR
11884 || TREE_CODE (expression) == CONST_CAST_EXPR
11885 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11886 || TREE_CODE (expression) == CAST_EXPR)
11888 tree type = TREE_TYPE (expression);
11889 if (dependent_type_p (type))
11891 /* A functional cast has a list of operands. */
11892 expression = TREE_OPERAND (expression, 0);
11895 /* If there are no operands, it must be an expression such
11896 as "int()". This should not happen for aggregate types
11897 because it would form non-constant expressions. */
11898 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
11902 if (TREE_CODE (expression) == TREE_LIST)
11906 if (value_dependent_expression_p (TREE_VALUE (expression)))
11908 expression = TREE_CHAIN (expression);
11910 while (expression);
11914 return value_dependent_expression_p (expression);
11916 /* A `sizeof' expression is value-dependent if the operand is
11918 if (TREE_CODE (expression) == SIZEOF_EXPR
11919 || TREE_CODE (expression) == ALIGNOF_EXPR)
11921 expression = TREE_OPERAND (expression, 0);
11922 if (TYPE_P (expression))
11923 return dependent_type_p (expression);
11924 return type_dependent_expression_p (expression);
11926 if (TREE_CODE (expression) == SCOPE_REF)
11927 return dependent_scope_ref_p (expression, value_dependent_expression_p);
11928 if (TREE_CODE (expression) == COMPONENT_REF)
11929 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
11930 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
11931 /* A constant expression is value-dependent if any subexpression is
11932 value-dependent. */
11933 if (EXPR_P (expression))
11935 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
11938 return (value_dependent_expression_p
11939 (TREE_OPERAND (expression, 0)));
11940 case tcc_comparison:
11942 return ((value_dependent_expression_p
11943 (TREE_OPERAND (expression, 0)))
11944 || (value_dependent_expression_p
11945 (TREE_OPERAND (expression, 1))));
11946 case tcc_expression:
11949 for (i = 0; i < first_rtl_op (TREE_CODE (expression)); ++i)
11950 /* In some cases, some of the operands may be missing.
11951 (For example, in the case of PREDECREMENT_EXPR, the
11952 amount to increment by may be missing.) That doesn't
11953 make the expression dependent. */
11954 if (TREE_OPERAND (expression, i)
11955 && (value_dependent_expression_p
11956 (TREE_OPERAND (expression, i))))
11960 case tcc_reference:
11961 case tcc_statement:
11962 /* These cannot be value dependent. */
11966 gcc_unreachable ();
11970 /* The expression is not value-dependent. */
11974 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11975 [temp.dep.expr]. */
11978 type_dependent_expression_p (tree expression)
11980 if (!processing_template_decl)
11983 if (expression == error_mark_node)
11986 /* An unresolved name is always dependent. */
11987 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11990 /* Some expression forms are never type-dependent. */
11991 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
11992 || TREE_CODE (expression) == SIZEOF_EXPR
11993 || TREE_CODE (expression) == ALIGNOF_EXPR
11994 || TREE_CODE (expression) == TYPEID_EXPR
11995 || TREE_CODE (expression) == DELETE_EXPR
11996 || TREE_CODE (expression) == VEC_DELETE_EXPR
11997 || TREE_CODE (expression) == THROW_EXPR)
12000 /* The types of these expressions depends only on the type to which
12001 the cast occurs. */
12002 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12003 || TREE_CODE (expression) == STATIC_CAST_EXPR
12004 || TREE_CODE (expression) == CONST_CAST_EXPR
12005 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12006 || TREE_CODE (expression) == CAST_EXPR)
12007 return dependent_type_p (TREE_TYPE (expression));
12009 /* The types of these expressions depends only on the type created
12010 by the expression. */
12011 if (TREE_CODE (expression) == NEW_EXPR
12012 || TREE_CODE (expression) == VEC_NEW_EXPR)
12014 /* For NEW_EXPR tree nodes created inside a template, either
12015 the object type itself or a TREE_LIST may appear as the
12017 tree type = TREE_OPERAND (expression, 1);
12018 if (TREE_CODE (type) == TREE_LIST)
12019 /* This is an array type. We need to check array dimensions
12021 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12022 || value_dependent_expression_p
12023 (TREE_OPERAND (TREE_VALUE (type), 1));
12025 return dependent_type_p (type);
12028 if (TREE_CODE (expression) == SCOPE_REF
12029 && dependent_scope_ref_p (expression,
12030 type_dependent_expression_p))
12033 if (TREE_CODE (expression) == FUNCTION_DECL
12034 && DECL_LANG_SPECIFIC (expression)
12035 && DECL_TEMPLATE_INFO (expression)
12036 && (any_dependent_template_arguments_p
12037 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12040 if (TREE_CODE (expression) == TEMPLATE_DECL
12041 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12044 if (TREE_TYPE (expression) == unknown_type_node)
12046 if (TREE_CODE (expression) == ADDR_EXPR)
12047 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12048 if (TREE_CODE (expression) == COMPONENT_REF
12049 || TREE_CODE (expression) == OFFSET_REF)
12051 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12053 expression = TREE_OPERAND (expression, 1);
12054 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12057 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12058 if (TREE_CODE (expression) == SCOPE_REF)
12061 if (TREE_CODE (expression) == BASELINK)
12062 expression = BASELINK_FUNCTIONS (expression);
12064 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12066 if (any_dependent_template_arguments_p
12067 (TREE_OPERAND (expression, 1)))
12069 expression = TREE_OPERAND (expression, 0);
12071 gcc_assert (TREE_CODE (expression) == OVERLOAD);
12075 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12077 expression = OVL_NEXT (expression);
12082 return (dependent_type_p (TREE_TYPE (expression)));
12085 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12086 contains a type-dependent expression. */
12089 any_type_dependent_arguments_p (tree args)
12093 tree arg = TREE_VALUE (args);
12095 if (type_dependent_expression_p (arg))
12097 args = TREE_CHAIN (args);
12102 /* Returns TRUE if the ARG (a template argument) is dependent. */
12105 dependent_template_arg_p (tree arg)
12107 if (!processing_template_decl)
12110 if (TREE_CODE (arg) == TEMPLATE_DECL
12111 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12112 return dependent_template_p (arg);
12113 else if (TYPE_P (arg))
12114 return dependent_type_p (arg);
12116 return (type_dependent_expression_p (arg)
12117 || value_dependent_expression_p (arg));
12120 /* Returns true if ARGS (a collection of template arguments) contains
12121 any dependent arguments. */
12124 any_dependent_template_arguments_p (tree args)
12132 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12134 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12135 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12136 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12143 /* Returns TRUE if the template TMPL is dependent. */
12146 dependent_template_p (tree tmpl)
12148 if (TREE_CODE (tmpl) == OVERLOAD)
12152 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12154 tmpl = OVL_CHAIN (tmpl);
12159 /* Template template parameters are dependent. */
12160 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12161 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12163 /* So are names that have not been looked up. */
12164 if (TREE_CODE (tmpl) == SCOPE_REF
12165 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12167 /* So are member templates of dependent classes. */
12168 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12169 return dependent_type_p (DECL_CONTEXT (tmpl));
12173 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12176 dependent_template_id_p (tree tmpl, tree args)
12178 return (dependent_template_p (tmpl)
12179 || any_dependent_template_arguments_p (args));
12182 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12183 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12184 can be found. Note that this function peers inside uninstantiated
12185 templates and therefore should be used only in extremely limited
12189 resolve_typename_type (tree type, bool only_current_p)
12197 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12199 scope = TYPE_CONTEXT (type);
12200 name = TYPE_IDENTIFIER (type);
12202 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12203 it first before we can figure out what NAME refers to. */
12204 if (TREE_CODE (scope) == TYPENAME_TYPE)
12205 scope = resolve_typename_type (scope, only_current_p);
12206 /* If we don't know what SCOPE refers to, then we cannot resolve the
12208 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12209 return error_mark_node;
12210 /* If the SCOPE is a template type parameter, we have no way of
12211 resolving the name. */
12212 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12214 /* If the SCOPE is not the current instantiation, there's no reason
12215 to look inside it. */
12216 if (only_current_p && !currently_open_class (scope))
12217 return error_mark_node;
12218 /* If SCOPE is a partial instantiation, it will not have a valid
12219 TYPE_FIELDS list, so use the original template. */
12220 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12221 /* Enter the SCOPE so that name lookup will be resolved as if we
12222 were in the class definition. In particular, SCOPE will no
12223 longer be considered a dependent type. */
12224 pop_p = push_scope (scope);
12225 /* Look up the declaration. */
12226 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12227 /* Obtain the set of qualifiers applied to the TYPE. */
12228 quals = cp_type_quals (type);
12229 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12230 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12232 type = error_mark_node;
12233 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12234 && TREE_CODE (decl) == TYPE_DECL)
12235 type = TREE_TYPE (decl);
12236 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12237 && DECL_CLASS_TEMPLATE_P (decl))
12241 /* Obtain the template and the arguments. */
12242 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12243 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12244 /* Instantiate the template. */
12245 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12246 /*entering_scope=*/0, tf_error | tf_user);
12249 type = error_mark_node;
12250 /* Qualify the resulting type. */
12251 if (type != error_mark_node && quals)
12252 type = cp_build_qualified_type (type, quals);
12253 /* Leave the SCOPE. */
12260 /* EXPR is an expression which is not type-dependent. Return a proxy
12261 for EXPR that can be used to compute the types of larger
12262 expressions containing EXPR. */
12265 build_non_dependent_expr (tree expr)
12269 /* Preserve null pointer constants so that the type of things like
12270 "p == 0" where "p" is a pointer can be determined. */
12271 if (null_ptr_cst_p (expr))
12273 /* Preserve OVERLOADs; the functions must be available to resolve
12275 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12276 TREE_OPERAND (expr, 0) : expr);
12277 if (TREE_CODE (inner_expr) == OVERLOAD
12278 || TREE_CODE (inner_expr) == FUNCTION_DECL
12279 || TREE_CODE (inner_expr) == TEMPLATE_DECL
12280 || TREE_CODE (inner_expr) == TEMPLATE_ID_EXPR)
12282 /* Preserve string constants; conversions from string constants to
12283 "char *" are allowed, even though normally a "const char *"
12284 cannot be used to initialize a "char *". */
12285 if (TREE_CODE (expr) == STRING_CST)
12287 /* Preserve arithmetic constants, as an optimization -- there is no
12288 reason to create a new node. */
12289 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12291 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12292 There is at least one place where we want to know that a
12293 particular expression is a throw-expression: when checking a ?:
12294 expression, there are special rules if the second or third
12295 argument is a throw-expression. */
12296 if (TREE_CODE (expr) == THROW_EXPR)
12299 if (TREE_CODE (expr) == COND_EXPR)
12300 return build3 (COND_EXPR,
12302 TREE_OPERAND (expr, 0),
12303 (TREE_OPERAND (expr, 1)
12304 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12305 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12306 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12307 if (TREE_CODE (expr) == COMPOUND_EXPR
12308 && !COMPOUND_EXPR_OVERLOADED (expr))
12309 return build2 (COMPOUND_EXPR,
12311 TREE_OPERAND (expr, 0),
12312 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12314 /* Otherwise, build a NON_DEPENDENT_EXPR.
12316 REFERENCE_TYPEs are not stripped for expressions in templates
12317 because doing so would play havoc with mangling. Consider, for
12320 template <typename T> void f<T& g>() { g(); }
12322 In the body of "f", the expression for "g" will have
12323 REFERENCE_TYPE, even though the standard says that it should
12324 not. The reason is that we must preserve the syntactic form of
12325 the expression so that mangling (say) "f<g>" inside the body of
12326 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12328 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12331 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12332 Return a new TREE_LIST with the various arguments replaced with
12333 equivalent non-dependent expressions. */
12336 build_non_dependent_args (tree args)
12341 new_args = NULL_TREE;
12342 for (a = args; a; a = TREE_CHAIN (a))
12343 new_args = tree_cons (NULL_TREE,
12344 build_non_dependent_expr (TREE_VALUE (a)),
12346 return nreverse (new_args);
12349 #include "gt-cp-pt.h"