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, 2005 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, 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, 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"
39 #include "cp-objcp-common.h"
40 #include "tree-inline.h"
47 #include "tree-iterator.h"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work.
56 The TREE_PURPOSE of each entry is either a DECL (for a function or
57 static data member), or a TYPE (for a class) indicating what we are
58 hoping to instantiate. The TREE_VALUE is not used. */
59 static GTY(()) tree pending_templates;
60 static GTY(()) tree last_pending_template;
62 int processing_template_parmlist;
63 static int template_header_count;
65 static GTY(()) tree saved_trees;
66 static GTY(()) varray_type inline_parm_levels;
67 static size_t inline_parm_levels_used;
69 static GTY(()) tree current_tinst_level;
71 static GTY(()) tree saved_access_scope;
73 /* Live only within one (recursive) call to tsubst_expr. We use
74 this to pass the statement expression node from the STMT_EXPR
75 to the EXPR_STMT that is its result. */
76 static tree cur_stmt_expr;
78 /* A map from local variable declarations in the body of the template
79 presently being instantiated to the corresponding instantiated
81 static htab_t local_specializations;
83 #define UNIFY_ALLOW_NONE 0
84 #define UNIFY_ALLOW_MORE_CV_QUAL 1
85 #define UNIFY_ALLOW_LESS_CV_QUAL 2
86 #define UNIFY_ALLOW_DERIVED 4
87 #define UNIFY_ALLOW_INTEGER 8
88 #define UNIFY_ALLOW_OUTER_LEVEL 16
89 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
90 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
92 static void push_access_scope (tree);
93 static void pop_access_scope (tree);
94 static int resolve_overloaded_unification (tree, tree, tree, tree,
95 unification_kind_t, int);
96 static int try_one_overload (tree, tree, tree, tree, tree,
97 unification_kind_t, int, bool);
98 static int unify (tree, tree, tree, tree, int);
99 static void add_pending_template (tree);
100 static void reopen_tinst_level (tree);
101 static tree classtype_mangled_name (tree);
102 static char* mangle_class_name_for_template (const char *, tree, tree);
103 static tree tsubst_initializer_list (tree, tree);
104 static tree get_class_bindings (tree, tree, tree);
105 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
106 static void tsubst_enum (tree, tree, tree);
107 static tree add_to_template_args (tree, tree);
108 static tree add_outermost_template_args (tree, tree);
109 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
110 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
111 static int type_unification_real (tree, tree, tree, tree,
112 int, unification_kind_t, int);
113 static void note_template_header (int);
114 static tree convert_nontype_argument_function (tree, tree);
115 static tree convert_nontype_argument (tree, tree);
116 static tree convert_template_argument (tree, tree, tree,
117 tsubst_flags_t, int, 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, bool);
132 static int template_decl_level (tree);
133 static int check_cv_quals_for_unify (int, tree, tree);
134 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
135 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
136 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
137 static void regenerate_decl_from_template (tree, tree);
138 static tree most_specialized (tree, tree, tree);
139 static tree most_specialized_class (tree, tree);
140 static int template_class_depth_real (tree, int);
141 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
142 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
143 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
144 static void check_specialization_scope (void);
145 static tree process_partial_specialization (tree);
146 static void set_current_access_from_decl (tree);
147 static void check_default_tmpl_args (tree, tree, int, int);
148 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
149 static tree get_template_base (tree, tree, tree, tree);
150 static int verify_class_unification (tree, tree, tree);
151 static tree try_class_unification (tree, tree, tree, tree);
152 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
154 static tree determine_specialization (tree, tree, tree *, int, int);
155 static int template_args_equal (tree, tree);
156 static void tsubst_default_arguments (tree);
157 static tree for_each_template_parm_r (tree *, int *, void *);
158 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
159 static void copy_default_args_to_explicit_spec (tree);
160 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
161 static int eq_local_specializations (const void *, const void *);
162 static bool dependent_type_p_r (tree);
163 static tree tsubst (tree, tree, tsubst_flags_t, tree);
164 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
165 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
167 /* Make the current scope suitable for access checking when we are
168 processing T. T can be FUNCTION_DECL for instantiated function
169 template, or VAR_DECL for static member variable (need by
170 instantiate_decl). */
173 push_access_scope (tree t)
175 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
176 || TREE_CODE (t) == VAR_DECL);
178 if (DECL_FRIEND_CONTEXT (t))
179 push_nested_class (DECL_FRIEND_CONTEXT (t));
180 else 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_FRIEND_CONTEXT (t) || 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 maybe_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 pedwarn (" 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 pedwarn (" 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;
827 VEC(tree,gc) *methods;
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 fn = retrieve_specialization (tmpl, args,
1143 /*class_specializations_p=*/false);
1144 /* We can sometimes try to re-register a specialization that we've
1145 already got. In particular, regenerate_decl_from_template calls
1146 duplicate_decls which will update the specialization list. But,
1147 we'll still get called again here anyhow. It's more convenient
1148 to simply allow this than to try to prevent it. */
1151 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1153 if (DECL_TEMPLATE_INSTANTIATION (fn))
1156 || DECL_EXPLICIT_INSTANTIATION (fn))
1158 error ("specialization of %qD after instantiation",
1164 /* This situation should occur only if the first
1165 specialization is an implicit instantiation, the
1166 second is an explicit specialization, and the
1167 implicit instantiation has not yet been used. That
1168 situation can occur if we have implicitly
1169 instantiated a member function and then specialized
1172 We can also wind up here if a friend declaration that
1173 looked like an instantiation turns out to be a
1176 template <class T> void foo(T);
1177 class S { friend void foo<>(int) };
1178 template <> void foo(int);
1180 We transform the existing DECL in place so that any
1181 pointers to it become pointers to the updated
1184 If there was a definition for the template, but not
1185 for the specialization, we want this to look as if
1186 there were no definition, and vice versa. */
1187 DECL_INITIAL (fn) = NULL_TREE;
1188 duplicate_decls (spec, fn);
1193 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1195 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
1196 /* Dup decl failed, but this is a new definition. Set the
1197 line number so any errors match this new
1199 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1205 /* A specialization must be declared in the same namespace as the
1206 template it is specializing. */
1207 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1208 && !check_specialization_namespace (tmpl))
1209 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1211 if (!optimize_specialization_lookup_p (tmpl))
1212 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1213 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1218 /* Unregister the specialization SPEC as a specialization of TMPL.
1219 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1220 if the SPEC was listed as a specialization of TMPL. */
1223 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1227 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1229 s = &TREE_CHAIN (*s))
1230 if (TREE_VALUE (*s) == spec)
1233 *s = TREE_CHAIN (*s);
1235 TREE_VALUE (*s) = new_spec;
1242 /* Compare an entry in the local specializations hash table P1 (which
1243 is really a pointer to a TREE_LIST) with P2 (which is really a
1247 eq_local_specializations (const void *p1, const void *p2)
1249 return TREE_VALUE ((tree) p1) == (tree) p2;
1252 /* Hash P1, an entry in the local specializations table. */
1255 hash_local_specialization (const void* p1)
1257 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1260 /* Like register_specialization, but for local declarations. We are
1261 registering SPEC, an instantiation of TMPL. */
1264 register_local_specialization (tree spec, tree tmpl)
1268 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1269 htab_hash_pointer (tmpl), INSERT);
1270 *slot = build_tree_list (spec, tmpl);
1273 /* Print the list of candidate FNS in an error message. */
1276 print_candidates (tree fns)
1280 const char *str = "candidates are:";
1282 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1286 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1287 error ("%s %+#D", str, OVL_CURRENT (f));
1292 /* Returns the template (one of the functions given by TEMPLATE_ID)
1293 which can be specialized to match the indicated DECL with the
1294 explicit template args given in TEMPLATE_ID. The DECL may be
1295 NULL_TREE if none is available. In that case, the functions in
1296 TEMPLATE_ID are non-members.
1298 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1299 specialization of a member template.
1301 The TEMPLATE_COUNT is the number of references to qualifying
1302 template classes that appeared in the name of the function. See
1303 check_explicit_specialization for a more accurate description.
1305 The template args (those explicitly specified and those deduced)
1306 are output in a newly created vector *TARGS_OUT.
1308 If it is impossible to determine the result, an error message is
1309 issued. The error_mark_node is returned to indicate failure. */
1312 determine_specialization (tree template_id,
1315 int need_member_template,
1320 tree explicit_targs;
1321 tree candidates = NULL_TREE;
1322 tree templates = NULL_TREE;
1324 struct cp_binding_level *b;
1326 *targs_out = NULL_TREE;
1328 if (template_id == error_mark_node)
1329 return error_mark_node;
1331 fns = TREE_OPERAND (template_id, 0);
1332 explicit_targs = TREE_OPERAND (template_id, 1);
1334 if (fns == error_mark_node)
1335 return error_mark_node;
1337 /* Check for baselinks. */
1338 if (BASELINK_P (fns))
1339 fns = BASELINK_FUNCTIONS (fns);
1341 if (!is_overloaded_fn (fns))
1343 error ("%qD is not a function template", fns);
1344 return error_mark_node;
1347 /* Count the number of template headers specified for this
1350 for (b = current_binding_level;
1351 b->kind == sk_template_parms;
1355 for (; fns; fns = OVL_NEXT (fns))
1357 tree fn = OVL_CURRENT (fns);
1359 if (TREE_CODE (fn) == TEMPLATE_DECL)
1361 tree decl_arg_types;
1364 /* DECL might be a specialization of FN. */
1366 /* Adjust the type of DECL in case FN is a static member. */
1367 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1368 if (DECL_STATIC_FUNCTION_P (fn)
1369 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1370 decl_arg_types = TREE_CHAIN (decl_arg_types);
1372 /* Check that the number of function parameters matches.
1374 template <class T> void f(int i = 0);
1375 template <> void f<int>();
1376 The specialization f<int> is invalid but is not caught
1377 by get_bindings below. */
1379 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1380 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1383 /* For a non-static member function, we need to make sure that
1384 the const qualification is the same. This can be done by
1385 checking the 'this' in the argument list. */
1386 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1387 && !same_type_p (TREE_VALUE (fn_arg_types),
1388 TREE_VALUE (decl_arg_types)))
1391 /* In case of explicit specialization, we need to check if
1392 the number of template headers appearing in the specialization
1393 is correct. This is usually done in check_explicit_specialization,
1394 but the check done there cannot be exhaustive when specializing
1395 member functions. Consider the following code:
1397 template <> void A<int>::f(int);
1398 template <> template <> void A<int>::f(int);
1400 Assuming that A<int> is not itself an explicit specialization
1401 already, the first line specializes "f" which is a non-template
1402 member function, whilst the second line specializes "f" which
1403 is a template member function. So both lines are syntactically
1404 correct, and check_explicit_specialization does not reject
1407 Here, we can do better, as we are matching the specialization
1408 against the declarations. We count the number of template
1409 headers, and we check if they match TEMPLATE_COUNT + 1
1410 (TEMPLATE_COUNT is the number of qualifying template classes,
1411 plus there must be another header for the member template
1414 Notice that if header_count is zero, this is not a
1415 specialization but rather a template instantiation, so there
1416 is no check we can perform here. */
1417 if (header_count && header_count != template_count + 1)
1420 /* Check that the number of template arguments at the
1421 innermost level for DECL is the same as for FN. */
1422 if (current_binding_level->kind == sk_template_parms
1423 && !current_binding_level->explicit_spec_p
1424 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1425 != TREE_VEC_LENGTH (TREE_VALUE (current_template_parms))))
1428 /* See whether this function might be a specialization of this
1430 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1433 /* We cannot deduce template arguments that when used to
1434 specialize TMPL will produce DECL. */
1437 /* Save this template, and the arguments deduced. */
1438 templates = tree_cons (targs, fn, templates);
1440 else if (need_member_template)
1441 /* FN is an ordinary member function, and we need a
1442 specialization of a member template. */
1444 else if (TREE_CODE (fn) != FUNCTION_DECL)
1445 /* We can get IDENTIFIER_NODEs here in certain erroneous
1448 else if (!DECL_FUNCTION_MEMBER_P (fn))
1449 /* This is just an ordinary non-member function. Nothing can
1450 be a specialization of that. */
1452 else if (DECL_ARTIFICIAL (fn))
1453 /* Cannot specialize functions that are created implicitly. */
1457 tree decl_arg_types;
1459 /* This is an ordinary member function. However, since
1460 we're here, we can assume it's enclosing class is a
1461 template class. For example,
1463 template <typename T> struct S { void f(); };
1464 template <> void S<int>::f() {}
1466 Here, S<int>::f is a non-template, but S<int> is a
1467 template class. If FN has the same type as DECL, we
1468 might be in business. */
1470 if (!DECL_TEMPLATE_INFO (fn))
1471 /* Its enclosing class is an explicit specialization
1472 of a template class. This is not a candidate. */
1475 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1476 TREE_TYPE (TREE_TYPE (fn))))
1477 /* The return types differ. */
1480 /* Adjust the type of DECL in case FN is a static member. */
1481 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1482 if (DECL_STATIC_FUNCTION_P (fn)
1483 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1484 decl_arg_types = TREE_CHAIN (decl_arg_types);
1486 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1489 candidates = tree_cons (NULL_TREE, fn, candidates);
1493 if (templates && TREE_CHAIN (templates))
1499 It is possible for a specialization with a given function
1500 signature to be instantiated from more than one function
1501 template. In such cases, explicit specification of the
1502 template arguments must be used to uniquely identify the
1503 function template specialization being specialized.
1505 Note that here, there's no suggestion that we're supposed to
1506 determine which of the candidate templates is most
1507 specialized. However, we, also have:
1511 Partial ordering of overloaded function template
1512 declarations is used in the following contexts to select
1513 the function template to which a function template
1514 specialization refers:
1516 -- when an explicit specialization refers to a function
1519 So, we do use the partial ordering rules, at least for now.
1520 This extension can only serve to make invalid programs valid,
1521 so it's safe. And, there is strong anecdotal evidence that
1522 the committee intended the partial ordering rules to apply;
1523 the EDG front-end has that behavior, and John Spicer claims
1524 that the committee simply forgot to delete the wording in
1525 [temp.expl.spec]. */
1526 tree tmpl = most_specialized (templates, decl, explicit_targs);
1527 if (tmpl && tmpl != error_mark_node)
1529 targs = get_bindings (tmpl, decl, explicit_targs, /*check_ret=*/true);
1530 templates = tree_cons (targs, tmpl, NULL_TREE);
1534 if (templates == NULL_TREE && candidates == NULL_TREE)
1536 error ("template-id %qD for %q+D does not match any template "
1537 "declaration", template_id, decl);
1538 return error_mark_node;
1540 else if ((templates && TREE_CHAIN (templates))
1541 || (candidates && TREE_CHAIN (candidates))
1542 || (templates && candidates))
1544 error ("ambiguous template specialization %qD for %q+D",
1546 chainon (candidates, templates);
1547 print_candidates (candidates);
1548 return error_mark_node;
1551 /* We have one, and exactly one, match. */
1554 /* It was a specialization of an ordinary member function in a
1556 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1557 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1560 /* It was a specialization of a template. */
1561 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1562 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1564 *targs_out = copy_node (targs);
1565 SET_TMPL_ARGS_LEVEL (*targs_out,
1566 TMPL_ARGS_DEPTH (*targs_out),
1567 TREE_PURPOSE (templates));
1570 *targs_out = TREE_PURPOSE (templates);
1571 return TREE_VALUE (templates);
1574 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1575 but with the default argument values filled in from those in the
1579 copy_default_args_to_explicit_spec_1 (tree spec_types,
1582 tree new_spec_types;
1587 if (spec_types == void_list_node)
1588 return void_list_node;
1590 /* Substitute into the rest of the list. */
1592 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1593 TREE_CHAIN (tmpl_types));
1595 /* Add the default argument for this parameter. */
1596 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1597 TREE_VALUE (spec_types),
1601 /* DECL is an explicit specialization. Replicate default arguments
1602 from the template it specializes. (That way, code like:
1604 template <class T> void f(T = 3);
1605 template <> void f(double);
1608 works, as required.) An alternative approach would be to look up
1609 the correct default arguments at the call-site, but this approach
1610 is consistent with how implicit instantiations are handled. */
1613 copy_default_args_to_explicit_spec (tree decl)
1618 tree new_spec_types;
1622 tree object_type = NULL_TREE;
1623 tree in_charge = NULL_TREE;
1624 tree vtt = NULL_TREE;
1626 /* See if there's anything we need to do. */
1627 tmpl = DECL_TI_TEMPLATE (decl);
1628 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1629 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1630 if (TREE_PURPOSE (t))
1635 old_type = TREE_TYPE (decl);
1636 spec_types = TYPE_ARG_TYPES (old_type);
1638 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1640 /* Remove the this pointer, but remember the object's type for
1642 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1643 spec_types = TREE_CHAIN (spec_types);
1644 tmpl_types = TREE_CHAIN (tmpl_types);
1646 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1648 /* DECL may contain more parameters than TMPL due to the extra
1649 in-charge parameter in constructors and destructors. */
1650 in_charge = spec_types;
1651 spec_types = TREE_CHAIN (spec_types);
1653 if (DECL_HAS_VTT_PARM_P (decl))
1656 spec_types = TREE_CHAIN (spec_types);
1660 /* Compute the merged default arguments. */
1662 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1664 /* Compute the new FUNCTION_TYPE. */
1668 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1673 /* Put the in-charge parameter back. */
1674 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1675 TREE_VALUE (in_charge),
1678 new_type = build_method_type_directly (object_type,
1679 TREE_TYPE (old_type),
1683 new_type = build_function_type (TREE_TYPE (old_type),
1685 new_type = cp_build_type_attribute_variant (new_type,
1686 TYPE_ATTRIBUTES (old_type));
1687 new_type = build_exception_variant (new_type,
1688 TYPE_RAISES_EXCEPTIONS (old_type));
1689 TREE_TYPE (decl) = new_type;
1692 /* Check to see if the function just declared, as indicated in
1693 DECLARATOR, and in DECL, is a specialization of a function
1694 template. We may also discover that the declaration is an explicit
1695 instantiation at this point.
1697 Returns DECL, or an equivalent declaration that should be used
1698 instead if all goes well. Issues an error message if something is
1699 amiss. Returns error_mark_node if the error is not easily
1702 FLAGS is a bitmask consisting of the following flags:
1704 2: The function has a definition.
1705 4: The function is a friend.
1707 The TEMPLATE_COUNT is the number of references to qualifying
1708 template classes that appeared in the name of the function. For
1711 template <class T> struct S { void f(); };
1714 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1715 classes are not counted in the TEMPLATE_COUNT, so that in
1717 template <class T> struct S {};
1718 template <> struct S<int> { void f(); }
1719 template <> void S<int>::f();
1721 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1722 invalid; there should be no template <>.)
1724 If the function is a specialization, it is marked as such via
1725 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1726 is set up correctly, and it is added to the list of specializations
1727 for that template. */
1730 check_explicit_specialization (tree declarator,
1735 int have_def = flags & 2;
1736 int is_friend = flags & 4;
1737 int specialization = 0;
1738 int explicit_instantiation = 0;
1739 int member_specialization = 0;
1740 tree ctype = DECL_CLASS_CONTEXT (decl);
1741 tree dname = DECL_NAME (decl);
1746 if (!processing_specialization)
1749 tsk = tsk_excessive_parms;
1752 tsk = current_tmpl_spec_kind (template_count);
1757 if (processing_specialization)
1760 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1762 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1765 /* This could be something like:
1767 template <class T> void f(T);
1768 class S { friend void f<>(int); } */
1772 /* This case handles bogus declarations like template <>
1773 template <class T> void f<int>(); */
1775 error ("template-id %qD in declaration of primary template",
1782 case tsk_invalid_member_spec:
1783 /* The error has already been reported in
1784 check_specialization_scope. */
1785 return error_mark_node;
1787 case tsk_invalid_expl_inst:
1788 error ("template parameter list used in explicit instantiation");
1794 error ("definition provided for explicit instantiation");
1796 explicit_instantiation = 1;
1799 case tsk_excessive_parms:
1800 case tsk_insufficient_parms:
1801 if (tsk == tsk_excessive_parms)
1802 error ("too many template parameter lists in declaration of %qD",
1804 else if (template_header_count)
1805 error("too few template parameter lists in declaration of %qD", decl);
1807 error("explicit specialization of %qD must be introduced by "
1808 "%<template <>%>", decl);
1812 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1814 member_specialization = 1;
1820 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1822 /* This case handles bogus declarations like template <>
1823 template <class T> void f<int>(); */
1825 if (uses_template_parms (declarator))
1826 error ("function template partial specialization %qD "
1827 "is not allowed", declarator);
1829 error ("template-id %qD in declaration of primary template",
1834 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1835 /* This is a specialization of a member template, without
1836 specialization the containing class. Something like:
1838 template <class T> struct S {
1839 template <class U> void f (U);
1841 template <> template <class U> void S<int>::f(U) {}
1843 That's a specialization -- but of the entire template. */
1851 if (specialization || member_specialization)
1853 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1854 for (; t; t = TREE_CHAIN (t))
1855 if (TREE_PURPOSE (t))
1858 ("default argument specified in explicit specialization");
1861 if (current_lang_name == lang_name_c)
1862 error ("template specialization with C linkage");
1865 if (specialization || member_specialization || explicit_instantiation)
1867 tree tmpl = NULL_TREE;
1868 tree targs = NULL_TREE;
1870 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1871 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1875 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1880 /* If there is no class context, the explicit instantiation
1881 must be at namespace scope. */
1882 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1884 /* Find the namespace binding, using the declaration
1886 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1887 if (!fns || !is_overloaded_fn (fns))
1889 error ("%qD is not a template function", dname);
1890 fns = error_mark_node;
1894 declarator = lookup_template_function (fns, NULL_TREE);
1897 if (declarator == error_mark_node)
1898 return error_mark_node;
1900 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1902 if (!explicit_instantiation)
1903 /* A specialization in class scope. This is invalid,
1904 but the error will already have been flagged by
1905 check_specialization_scope. */
1906 return error_mark_node;
1909 /* It's not valid to write an explicit instantiation in
1912 class C { template void f(); }
1914 This case is caught by the parser. However, on
1917 template class C { void f(); };
1919 (which is invalid) we can get here. The error will be
1926 else if (ctype != NULL_TREE
1927 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1930 /* Find the list of functions in ctype that have the same
1931 name as the declared function. */
1932 tree name = TREE_OPERAND (declarator, 0);
1933 tree fns = NULL_TREE;
1936 if (constructor_name_p (name, ctype))
1938 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1940 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1941 : !CLASSTYPE_DESTRUCTORS (ctype))
1943 /* From [temp.expl.spec]:
1945 If such an explicit specialization for the member
1946 of a class template names an implicitly-declared
1947 special member function (clause _special_), the
1948 program is ill-formed.
1950 Similar language is found in [temp.explicit]. */
1951 error ("specialization of implicitly-declared special member function");
1952 return error_mark_node;
1955 name = is_constructor ? ctor_identifier : dtor_identifier;
1958 if (!DECL_CONV_FN_P (decl))
1960 idx = lookup_fnfields_1 (ctype, name);
1962 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1966 VEC(tree,gc) *methods;
1969 /* For a type-conversion operator, we cannot do a
1970 name-based lookup. We might be looking for `operator
1971 int' which will be a specialization of `operator T'.
1972 So, we find *all* the conversion operators, and then
1973 select from them. */
1976 methods = CLASSTYPE_METHOD_VEC (ctype);
1978 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1979 VEC_iterate (tree, methods, idx, ovl);
1982 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1983 /* There are no more conversion functions. */
1986 /* Glue all these conversion functions together
1987 with those we already have. */
1988 for (; ovl; ovl = OVL_NEXT (ovl))
1989 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1993 if (fns == NULL_TREE)
1995 error ("no member function %qD declared in %qT", name, ctype);
1996 return error_mark_node;
1999 TREE_OPERAND (declarator, 0) = fns;
2002 /* Figure out what exactly is being specialized at this point.
2003 Note that for an explicit instantiation, even one for a
2004 member function, we cannot tell apriori whether the
2005 instantiation is for a member template, or just a member
2006 function of a template class. Even if a member template is
2007 being instantiated, the member template arguments may be
2008 elided if they can be deduced from the rest of the
2010 tmpl = determine_specialization (declarator, decl,
2012 member_specialization,
2015 if (!tmpl || tmpl == error_mark_node)
2016 /* We couldn't figure out what this declaration was
2018 return error_mark_node;
2021 tree gen_tmpl = most_general_template (tmpl);
2023 if (explicit_instantiation)
2025 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2026 is done by do_decl_instantiation later. */
2028 int arg_depth = TMPL_ARGS_DEPTH (targs);
2029 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2031 if (arg_depth > parm_depth)
2033 /* If TMPL is not the most general template (for
2034 example, if TMPL is a friend template that is
2035 injected into namespace scope), then there will
2036 be too many levels of TARGS. Remove some of them
2041 new_targs = make_tree_vec (parm_depth);
2042 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2043 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2044 = TREE_VEC_ELT (targs, i);
2048 return instantiate_template (tmpl, targs, tf_error);
2051 /* If we thought that the DECL was a member function, but it
2052 turns out to be specializing a static member function,
2053 make DECL a static member function as well. */
2054 if (DECL_STATIC_FUNCTION_P (tmpl)
2055 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2056 revert_static_member_fn (decl);
2058 /* If this is a specialization of a member template of a
2059 template class. In we want to return the TEMPLATE_DECL,
2060 not the specialization of it. */
2061 if (tsk == tsk_template)
2063 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2064 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2067 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2068 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2069 = DECL_SOURCE_LOCATION (decl);
2070 /* We want to use the argument list specified in the
2071 definition, not in the original declaration. */
2072 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2073 = DECL_ARGUMENTS (decl);
2078 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2079 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2081 /* Inherit default function arguments from the template
2082 DECL is specializing. */
2083 copy_default_args_to_explicit_spec (decl);
2085 /* This specialization has the same protection as the
2086 template it specializes. */
2087 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2088 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2090 if (is_friend && !have_def)
2091 /* This is not really a declaration of a specialization.
2092 It's just the name of an instantiation. But, it's not
2093 a request for an instantiation, either. */
2094 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2095 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2096 /* This is indeed a specialization. In case of constructors
2097 and destructors, we need in-charge and not-in-charge
2098 versions in V3 ABI. */
2099 clone_function_decl (decl, /*update_method_vec_p=*/0);
2101 /* Register this specialization so that we can find it
2103 decl = register_specialization (decl, gen_tmpl, targs);
2110 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2111 parameters. These are represented in the same format used for
2112 DECL_TEMPLATE_PARMS. */
2115 comp_template_parms (tree parms1, tree parms2)
2120 if (parms1 == parms2)
2123 for (p1 = parms1, p2 = parms2;
2124 p1 != NULL_TREE && p2 != NULL_TREE;
2125 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2127 tree t1 = TREE_VALUE (p1);
2128 tree t2 = TREE_VALUE (p2);
2131 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2132 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2134 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2137 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2139 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2140 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2142 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2145 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2147 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2152 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2153 /* One set of parameters has more parameters lists than the
2160 /* Complain if DECL shadows a template parameter.
2162 [temp.local]: A template-parameter shall not be redeclared within its
2163 scope (including nested scopes). */
2166 check_template_shadow (tree decl)
2170 /* If we're not in a template, we can't possibly shadow a template
2172 if (!current_template_parms)
2175 /* Figure out what we're shadowing. */
2176 if (TREE_CODE (decl) == OVERLOAD)
2177 decl = OVL_CURRENT (decl);
2178 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2180 /* If there's no previous binding for this name, we're not shadowing
2181 anything, let alone a template parameter. */
2185 /* If we're not shadowing a template parameter, we're done. Note
2186 that OLDDECL might be an OVERLOAD (or perhaps even an
2187 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2189 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2192 /* We check for decl != olddecl to avoid bogus errors for using a
2193 name inside a class. We check TPFI to avoid duplicate errors for
2194 inline member templates. */
2196 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2199 error ("declaration of %q+#D", decl);
2200 error (" shadows template parm %q+#D", olddecl);
2203 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2204 ORIG_LEVEL, DECL, and TYPE. */
2207 build_template_parm_index (int index,
2213 tree t = make_node (TEMPLATE_PARM_INDEX);
2214 TEMPLATE_PARM_IDX (t) = index;
2215 TEMPLATE_PARM_LEVEL (t) = level;
2216 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2217 TEMPLATE_PARM_DECL (t) = decl;
2218 TREE_TYPE (t) = type;
2219 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2220 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2221 TREE_READONLY (t) = TREE_READONLY (decl);
2226 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2227 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2228 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2229 new one is created. */
2232 reduce_template_parm_level (tree index, tree type, int levels)
2234 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2235 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2236 != TEMPLATE_PARM_LEVEL (index) - levels))
2238 tree orig_decl = TEMPLATE_PARM_DECL (index);
2241 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2242 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2243 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2244 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2245 DECL_ARTIFICIAL (decl) = 1;
2246 SET_DECL_TEMPLATE_PARM_P (decl);
2248 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2249 TEMPLATE_PARM_LEVEL (index) - levels,
2250 TEMPLATE_PARM_ORIG_LEVEL (index),
2252 TEMPLATE_PARM_DESCENDANTS (index) = t;
2254 /* Template template parameters need this. */
2255 DECL_TEMPLATE_PARMS (decl)
2256 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2259 return TEMPLATE_PARM_DESCENDANTS (index);
2262 /* Process information from new template parameter NEXT and append it to the
2263 LIST being built. This new parameter is a non-type parameter iff
2264 IS_NON_TYPE is true. */
2267 process_template_parm (tree list, tree next, bool is_non_type)
2275 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2276 defval = TREE_PURPOSE (parm);
2280 tree p = TREE_VALUE (tree_last (list));
2282 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2283 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2285 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2293 parm = TREE_VALUE (parm);
2295 SET_DECL_TEMPLATE_PARM_P (parm);
2299 The top-level cv-qualifiers on the template-parameter are
2300 ignored when determining its type. */
2301 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2303 /* A template parameter is not modifiable. */
2304 TREE_CONSTANT (parm) = 1;
2305 TREE_INVARIANT (parm) = 1;
2306 TREE_READONLY (parm) = 1;
2307 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2308 TREE_TYPE (parm) = void_type_node;
2309 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2310 TREE_CONSTANT (decl) = 1;
2311 TREE_INVARIANT (decl) = 1;
2312 TREE_READONLY (decl) = 1;
2313 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2314 = build_template_parm_index (idx, processing_template_decl,
2315 processing_template_decl,
2316 decl, TREE_TYPE (parm));
2321 parm = TREE_VALUE (TREE_VALUE (parm));
2323 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2325 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2326 /* This is for distinguishing between real templates and template
2327 template parameters */
2328 TREE_TYPE (parm) = t;
2329 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2334 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2335 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2336 decl = build_decl (TYPE_DECL, parm, t);
2339 TYPE_NAME (t) = decl;
2340 TYPE_STUB_DECL (t) = decl;
2342 TEMPLATE_TYPE_PARM_INDEX (t)
2343 = build_template_parm_index (idx, processing_template_decl,
2344 processing_template_decl,
2345 decl, TREE_TYPE (parm));
2347 DECL_ARTIFICIAL (decl) = 1;
2348 SET_DECL_TEMPLATE_PARM_P (decl);
2350 parm = build_tree_list (defval, parm);
2351 return chainon (list, parm);
2354 /* The end of a template parameter list has been reached. Process the
2355 tree list into a parameter vector, converting each parameter into a more
2356 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2360 end_template_parm_list (tree parms)
2364 tree saved_parmlist = make_tree_vec (list_length (parms));
2366 current_template_parms
2367 = tree_cons (size_int (processing_template_decl),
2368 saved_parmlist, current_template_parms);
2370 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2372 next = TREE_CHAIN (parm);
2373 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2374 TREE_CHAIN (parm) = NULL_TREE;
2377 --processing_template_parmlist;
2379 return saved_parmlist;
2382 /* end_template_decl is called after a template declaration is seen. */
2385 end_template_decl (void)
2387 reset_specialization ();
2389 if (! processing_template_decl)
2392 /* This matches the pushlevel in begin_template_parm_list. */
2395 --processing_template_decl;
2396 current_template_parms = TREE_CHAIN (current_template_parms);
2399 /* Given a template argument vector containing the template PARMS.
2400 The innermost PARMS are given first. */
2403 current_template_args (void)
2406 tree args = NULL_TREE;
2407 int length = TMPL_PARMS_DEPTH (current_template_parms);
2410 /* If there is only one level of template parameters, we do not
2411 create a TREE_VEC of TREE_VECs. Instead, we return a single
2412 TREE_VEC containing the arguments. */
2414 args = make_tree_vec (length);
2416 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2418 tree a = copy_node (TREE_VALUE (header));
2421 TREE_TYPE (a) = NULL_TREE;
2422 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2424 tree t = TREE_VEC_ELT (a, i);
2426 /* T will be a list if we are called from within a
2427 begin/end_template_parm_list pair, but a vector directly
2428 if within a begin/end_member_template_processing pair. */
2429 if (TREE_CODE (t) == TREE_LIST)
2433 if (TREE_CODE (t) == TYPE_DECL
2434 || TREE_CODE (t) == TEMPLATE_DECL)
2437 t = DECL_INITIAL (t);
2438 TREE_VEC_ELT (a, i) = t;
2443 TREE_VEC_ELT (args, --l) = a;
2451 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2452 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2453 a member template. Used by push_template_decl below. */
2456 build_template_decl (tree decl, tree parms, bool member_template_p)
2458 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2459 DECL_TEMPLATE_PARMS (tmpl) = parms;
2460 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2461 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2462 if (DECL_LANG_SPECIFIC (decl))
2464 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2465 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2466 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2467 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2468 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2469 if (DECL_OVERLOADED_OPERATOR_P (decl))
2470 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2471 DECL_OVERLOADED_OPERATOR_P (decl));
2477 struct template_parm_data
2479 /* The level of the template parameters we are currently
2483 /* The index of the specialization argument we are currently
2487 /* An array whose size is the number of template parameters. The
2488 elements are nonzero if the parameter has been used in any one
2489 of the arguments processed so far. */
2492 /* An array whose size is the number of template arguments. The
2493 elements are nonzero if the argument makes use of template
2494 parameters of this level. */
2495 int* arg_uses_template_parms;
2498 /* Subroutine of push_template_decl used to see if each template
2499 parameter in a partial specialization is used in the explicit
2500 argument list. If T is of the LEVEL given in DATA (which is
2501 treated as a template_parm_data*), then DATA->PARMS is marked
2505 mark_template_parm (tree t, void* data)
2509 struct template_parm_data* tpd = (struct template_parm_data*) data;
2511 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2513 level = TEMPLATE_PARM_LEVEL (t);
2514 idx = TEMPLATE_PARM_IDX (t);
2518 level = TEMPLATE_TYPE_LEVEL (t);
2519 idx = TEMPLATE_TYPE_IDX (t);
2522 if (level == tpd->level)
2524 tpd->parms[idx] = 1;
2525 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2528 /* Return zero so that for_each_template_parm will continue the
2529 traversal of the tree; we want to mark *every* template parm. */
2533 /* Process the partial specialization DECL. */
2536 process_partial_specialization (tree decl)
2538 tree type = TREE_TYPE (decl);
2539 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2540 tree specargs = CLASSTYPE_TI_ARGS (type);
2541 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2542 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2543 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2544 int nargs = TREE_VEC_LENGTH (inner_args);
2545 int ntparms = TREE_VEC_LENGTH (inner_parms);
2547 int did_error_intro = 0;
2548 struct template_parm_data tpd;
2549 struct template_parm_data tpd2;
2551 /* We check that each of the template parameters given in the
2552 partial specialization is used in the argument list to the
2553 specialization. For example:
2555 template <class T> struct S;
2556 template <class T> struct S<T*>;
2558 The second declaration is OK because `T*' uses the template
2559 parameter T, whereas
2561 template <class T> struct S<int>;
2563 is no good. Even trickier is:
2574 The S2<T> declaration is actually invalid; it is a
2575 full-specialization. Of course,
2578 struct S2<T (*)(U)>;
2580 or some such would have been OK. */
2581 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2582 tpd.parms = alloca (sizeof (int) * ntparms);
2583 memset (tpd.parms, 0, sizeof (int) * ntparms);
2585 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2586 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2587 for (i = 0; i < nargs; ++i)
2589 tpd.current_arg = i;
2590 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2591 &mark_template_parm,
2595 for (i = 0; i < ntparms; ++i)
2596 if (tpd.parms[i] == 0)
2598 /* One of the template parms was not used in the
2600 if (!did_error_intro)
2602 error ("template parameters not used in partial specialization:");
2603 did_error_intro = 1;
2606 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2609 /* [temp.class.spec]
2611 The argument list of the specialization shall not be identical to
2612 the implicit argument list of the primary template. */
2613 if (comp_template_args
2615 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2617 error ("partial specialization %qT does not specialize any template arguments", type);
2619 /* [temp.class.spec]
2621 A partially specialized non-type argument expression shall not
2622 involve template parameters of the partial specialization except
2623 when the argument expression is a simple identifier.
2625 The type of a template parameter corresponding to a specialized
2626 non-type argument shall not be dependent on a parameter of the
2628 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2630 for (i = 0; i < nargs; ++i)
2632 tree arg = TREE_VEC_ELT (inner_args, i);
2633 if (/* These first two lines are the `non-type' bit. */
2635 && TREE_CODE (arg) != TEMPLATE_DECL
2636 /* This next line is the `argument expression is not just a
2637 simple identifier' condition and also the `specialized
2638 non-type argument' bit. */
2639 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2641 if (tpd.arg_uses_template_parms[i])
2642 error ("template argument %qE involves template parameter(s)", arg);
2645 /* Look at the corresponding template parameter,
2646 marking which template parameters its type depends
2649 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2654 /* We haven't yet initialized TPD2. Do so now. */
2655 tpd2.arg_uses_template_parms
2656 = alloca (sizeof (int) * nargs);
2657 /* The number of parameters here is the number in the
2658 main template, which, as checked in the assertion
2660 tpd2.parms = alloca (sizeof (int) * nargs);
2662 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2665 /* Mark the template parameters. But this time, we're
2666 looking for the template parameters of the main
2667 template, not in the specialization. */
2668 tpd2.current_arg = i;
2669 tpd2.arg_uses_template_parms[i] = 0;
2670 memset (tpd2.parms, 0, sizeof (int) * nargs);
2671 for_each_template_parm (type,
2672 &mark_template_parm,
2676 if (tpd2.arg_uses_template_parms [i])
2678 /* The type depended on some template parameters.
2679 If they are fully specialized in the
2680 specialization, that's OK. */
2682 for (j = 0; j < nargs; ++j)
2683 if (tpd2.parms[j] != 0
2684 && tpd.arg_uses_template_parms [j])
2686 error ("type %qT of template argument %qE depends "
2687 "on template parameter(s)",
2697 if (retrieve_specialization (maintmpl, specargs,
2698 /*class_specializations_p=*/true))
2699 /* We've already got this specialization. */
2702 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2703 = tree_cons (inner_args, inner_parms,
2704 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2705 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2709 /* Check that a template declaration's use of default arguments is not
2710 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2711 nonzero if DECL is the thing declared by a primary template.
2712 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2715 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2718 int last_level_to_check;
2723 A default template-argument shall not be specified in a
2724 function template declaration or a function template definition, nor
2725 in the template-parameter-list of the definition of a member of a
2728 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2729 /* You can't have a function template declaration in a local
2730 scope, nor you can you define a member of a class template in a
2734 if (current_class_type
2735 && !TYPE_BEING_DEFINED (current_class_type)
2736 && DECL_LANG_SPECIFIC (decl)
2737 /* If this is either a friend defined in the scope of the class
2738 or a member function. */
2739 && (DECL_FUNCTION_MEMBER_P (decl)
2740 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2741 : DECL_FRIEND_CONTEXT (decl)
2742 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2744 /* And, if it was a member function, it really was defined in
2745 the scope of the class. */
2746 && (!DECL_FUNCTION_MEMBER_P (decl)
2747 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2748 /* We already checked these parameters when the template was
2749 declared, so there's no need to do it again now. This function
2750 was defined in class scope, but we're processing it's body now
2751 that the class is complete. */
2756 If a template-parameter has a default template-argument, all
2757 subsequent template-parameters shall have a default
2758 template-argument supplied. */
2759 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2761 tree inner_parms = TREE_VALUE (parm_level);
2762 int ntparms = TREE_VEC_LENGTH (inner_parms);
2763 int seen_def_arg_p = 0;
2766 for (i = 0; i < ntparms; ++i)
2768 tree parm = TREE_VEC_ELT (inner_parms, i);
2769 if (TREE_PURPOSE (parm))
2771 else if (seen_def_arg_p)
2773 error ("no default argument for %qD", TREE_VALUE (parm));
2774 /* For better subsequent error-recovery, we indicate that
2775 there should have been a default argument. */
2776 TREE_PURPOSE (parm) = error_mark_node;
2781 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2782 /* For an ordinary class template, default template arguments are
2783 allowed at the innermost level, e.g.:
2784 template <class T = int>
2786 but, in a partial specialization, they're not allowed even
2787 there, as we have in [temp.class.spec]:
2789 The template parameter list of a specialization shall not
2790 contain default template argument values.
2792 So, for a partial specialization, or for a function template,
2793 we look at all of them. */
2796 /* But, for a primary class template that is not a partial
2797 specialization we look at all template parameters except the
2799 parms = TREE_CHAIN (parms);
2801 /* Figure out what error message to issue. */
2802 if (TREE_CODE (decl) == FUNCTION_DECL)
2803 msg = "default template arguments may not be used in function templates";
2804 else if (is_partial)
2805 msg = "default template arguments may not be used in partial specializations";
2807 msg = "default argument for template parameter for class enclosing %qD";
2809 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2810 /* If we're inside a class definition, there's no need to
2811 examine the parameters to the class itself. On the one
2812 hand, they will be checked when the class is defined, and,
2813 on the other, default arguments are valid in things like:
2814 template <class T = double>
2815 struct S { template <class U> void f(U); };
2816 Here the default argument for `S' has no bearing on the
2817 declaration of `f'. */
2818 last_level_to_check = template_class_depth (current_class_type) + 1;
2820 /* Check everything. */
2821 last_level_to_check = 0;
2823 for (parm_level = parms;
2824 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2825 parm_level = TREE_CHAIN (parm_level))
2827 tree inner_parms = TREE_VALUE (parm_level);
2831 ntparms = TREE_VEC_LENGTH (inner_parms);
2832 for (i = 0; i < ntparms; ++i)
2833 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2841 /* Clear out the default argument so that we are not
2843 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2846 /* At this point, if we're still interested in issuing messages,
2847 they must apply to classes surrounding the object declared. */
2849 msg = "default argument for template parameter for class enclosing %qD";
2853 /* Worker for push_template_decl_real, called via
2854 for_each_template_parm. DATA is really an int, indicating the
2855 level of the parameters we are interested in. If T is a template
2856 parameter of that level, return nonzero. */
2859 template_parm_this_level_p (tree t, void* data)
2861 int this_level = *(int *)data;
2864 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2865 level = TEMPLATE_PARM_LEVEL (t);
2867 level = TEMPLATE_TYPE_LEVEL (t);
2868 return level == this_level;
2871 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2872 parameters given by current_template_args, or reuses a
2873 previously existing one, if appropriate. Returns the DECL, or an
2874 equivalent one, if it is replaced via a call to duplicate_decls.
2876 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2879 push_template_decl_real (tree decl, int is_friend)
2887 int new_template_p = 0;
2888 /* True if the template is a member template, in the sense of
2890 bool member_template_p = false;
2892 if (decl == error_mark_node)
2895 /* See if this is a partial specialization. */
2896 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2897 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2898 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2900 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2903 /* For a friend, we want the context of the friend function, not
2904 the type of which it is a friend. */
2905 ctx = DECL_CONTEXT (decl);
2906 else if (CP_DECL_CONTEXT (decl)
2907 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2908 /* In the case of a virtual function, we want the class in which
2910 ctx = CP_DECL_CONTEXT (decl);
2912 /* Otherwise, if we're currently defining some class, the DECL
2913 is assumed to be a member of the class. */
2914 ctx = current_scope ();
2916 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2919 if (!DECL_CONTEXT (decl))
2920 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2922 /* See if this is a primary template. */
2923 primary = template_parm_scope_p ();
2927 if (DECL_CLASS_SCOPE_P (decl))
2928 member_template_p = true;
2929 if (current_lang_name == lang_name_c)
2930 error ("template with C linkage");
2931 else if (TREE_CODE (decl) == TYPE_DECL
2932 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2933 error ("template class without a name");
2934 else if (TREE_CODE (decl) == FUNCTION_DECL)
2936 if (DECL_DESTRUCTOR_P (decl))
2940 A destructor shall not be a member template. */
2941 error ("destructor %qD declared as member template", decl);
2942 return error_mark_node;
2944 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2945 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2946 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2947 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2948 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2949 == void_list_node)))
2951 /* [basic.stc.dynamic.allocation]
2953 An allocation function can be a function
2954 template. ... Template allocation functions shall
2955 have two or more parameters. */
2956 error ("invalid template declaration of %qD", decl);
2960 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2961 && CLASS_TYPE_P (TREE_TYPE (decl)))
2962 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx)))
2966 error ("template declaration of %q#D", decl);
2967 return error_mark_node;
2971 /* Check to see that the rules regarding the use of default
2972 arguments are not being violated. */
2973 check_default_tmpl_args (decl, current_template_parms,
2974 primary, is_partial);
2977 return process_partial_specialization (decl);
2979 args = current_template_args ();
2982 || TREE_CODE (ctx) == FUNCTION_DECL
2983 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
2984 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
2986 if (DECL_LANG_SPECIFIC (decl)
2987 && DECL_TEMPLATE_INFO (decl)
2988 && DECL_TI_TEMPLATE (decl))
2989 tmpl = DECL_TI_TEMPLATE (decl);
2990 /* If DECL is a TYPE_DECL for a class-template, then there won't
2991 be DECL_LANG_SPECIFIC. The information equivalent to
2992 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2993 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
2994 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2995 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2997 /* Since a template declaration already existed for this
2998 class-type, we must be redeclaring it here. Make sure
2999 that the redeclaration is valid. */
3000 redeclare_class_template (TREE_TYPE (decl),
3001 current_template_parms);
3002 /* We don't need to create a new TEMPLATE_DECL; just use the
3003 one we already had. */
3004 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3008 tmpl = build_template_decl (decl, current_template_parms,
3012 if (DECL_LANG_SPECIFIC (decl)
3013 && DECL_TEMPLATE_SPECIALIZATION (decl))
3015 /* A specialization of a member template of a template
3017 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3018 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3019 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3025 tree a, t, current, parms;
3028 if (TREE_CODE (decl) == TYPE_DECL)
3030 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3031 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3032 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3033 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3034 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3037 error ("%qD does not declare a template type", decl);
3041 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3043 error ("template definition of non-template %q#D", decl);
3047 tmpl = DECL_TI_TEMPLATE (decl);
3049 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3050 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3051 && DECL_TEMPLATE_SPECIALIZATION (decl)
3052 && DECL_MEMBER_TEMPLATE_P (tmpl))
3056 /* The declaration is a specialization of a member
3057 template, declared outside the class. Therefore, the
3058 innermost template arguments will be NULL, so we
3059 replace them with the arguments determined by the
3060 earlier call to check_explicit_specialization. */
3061 args = DECL_TI_ARGS (decl);
3064 = build_template_decl (decl, current_template_parms,
3066 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3067 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3068 DECL_TI_TEMPLATE (decl) = new_tmpl;
3069 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3070 DECL_TEMPLATE_INFO (new_tmpl)
3071 = tree_cons (tmpl, args, NULL_TREE);
3073 register_specialization (new_tmpl,
3074 most_general_template (tmpl),
3079 /* Make sure the template headers we got make sense. */
3081 parms = DECL_TEMPLATE_PARMS (tmpl);
3082 i = TMPL_PARMS_DEPTH (parms);
3083 if (TMPL_ARGS_DEPTH (args) != i)
3085 error ("expected %d levels of template parms for %q#D, got %d",
3086 i, decl, TMPL_ARGS_DEPTH (args));
3089 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3091 a = TMPL_ARGS_LEVEL (args, i);
3092 t = INNERMOST_TEMPLATE_PARMS (parms);
3094 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3096 if (current == decl)
3097 error ("got %d template parameters for %q#D",
3098 TREE_VEC_LENGTH (a), decl);
3100 error ("got %d template parameters for %q#T",
3101 TREE_VEC_LENGTH (a), current);
3102 error (" but %d required", TREE_VEC_LENGTH (t));
3105 /* Perhaps we should also check that the parms are used in the
3106 appropriate qualifying scopes in the declarator? */
3108 if (current == decl)
3111 current = TYPE_CONTEXT (current);
3115 DECL_TEMPLATE_RESULT (tmpl) = decl;
3116 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3118 /* Push template declarations for global functions and types. Note
3119 that we do not try to push a global template friend declared in a
3120 template class; such a thing may well depend on the template
3121 parameters of the class. */
3122 if (new_template_p && !ctx
3123 && !(is_friend && template_class_depth (current_class_type) > 0))
3125 tmpl = pushdecl_namespace_level (tmpl);
3126 if (tmpl == error_mark_node)
3127 return error_mark_node;
3129 /* Hide template friend classes that haven't been declared yet. */
3130 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
3132 DECL_ANTICIPATED (tmpl) = 1;
3133 DECL_FRIEND_P (tmpl) = 1;
3139 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3140 if (DECL_CONV_FN_P (tmpl))
3142 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3144 /* It is a conversion operator. See if the type converted to
3145 depends on innermost template operands. */
3147 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3149 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3153 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3154 back to its most general template. If TMPL is a specialization,
3155 ARGS may only have the innermost set of arguments. Add the missing
3156 argument levels if necessary. */
3157 if (DECL_TEMPLATE_INFO (tmpl))
3158 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3160 info = tree_cons (tmpl, args, NULL_TREE);
3162 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3164 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3165 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3166 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3167 /* Don't change the name if we've already set it up. */
3168 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3169 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3171 else if (DECL_LANG_SPECIFIC (decl))
3172 DECL_TEMPLATE_INFO (decl) = info;
3174 return DECL_TEMPLATE_RESULT (tmpl);
3178 push_template_decl (tree decl)
3180 return push_template_decl_real (decl, 0);
3183 /* Called when a class template TYPE is redeclared with the indicated
3184 template PARMS, e.g.:
3186 template <class T> struct S;
3187 template <class T> struct S {}; */
3190 redeclare_class_template (tree type, tree parms)
3196 if (!TYPE_TEMPLATE_INFO (type))
3198 error ("%qT is not a template type", type);
3202 tmpl = TYPE_TI_TEMPLATE (type);
3203 if (!PRIMARY_TEMPLATE_P (tmpl))
3204 /* The type is nested in some template class. Nothing to worry
3205 about here; there are no new template parameters for the nested
3211 error ("template specifiers not specified in declaration of %qD",
3216 parms = INNERMOST_TEMPLATE_PARMS (parms);
3217 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3219 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3221 error ("previous declaration %q+D", tmpl);
3222 error ("used %d template parameter(s) instead of %d",
3223 TREE_VEC_LENGTH (tmpl_parms),
3224 TREE_VEC_LENGTH (parms));
3228 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3230 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3231 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3232 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3233 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3235 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3237 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3238 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3239 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3241 error ("template parameter %q+#D", tmpl_parm);
3242 error ("redeclared here as %q#D", parm);
3246 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3248 /* We have in [temp.param]:
3250 A template-parameter may not be given default arguments
3251 by two different declarations in the same scope. */
3252 error ("redefinition of default argument for %q#D", parm);
3253 error ("%J original definition appeared here", tmpl_parm);
3257 if (parm_default != NULL_TREE)
3258 /* Update the previous template parameters (which are the ones
3259 that will really count) with the new default value. */
3260 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3261 else if (tmpl_default != NULL_TREE)
3262 /* Update the new parameters, too; they'll be used as the
3263 parameters for any members. */
3264 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3268 /* Simplify EXPR if it is a non-dependent expression. Returns the
3269 (possibly simplified) expression. */
3272 fold_non_dependent_expr (tree expr)
3274 /* If we're in a template, but EXPR isn't value dependent, simplify
3275 it. We're supposed to treat:
3277 template <typename T> void f(T[1 + 1]);
3278 template <typename T> void f(T[2]);
3280 as two declarations of the same function, for example. */
3281 if (processing_template_decl
3282 && !type_dependent_expression_p (expr)
3283 && !value_dependent_expression_p (expr))
3285 HOST_WIDE_INT saved_processing_template_decl;
3287 saved_processing_template_decl = processing_template_decl;
3288 processing_template_decl = 0;
3289 expr = tsubst_copy_and_build (expr,
3292 /*in_decl=*/NULL_TREE,
3293 /*function_p=*/false);
3294 processing_template_decl = saved_processing_template_decl;
3299 /* EXPR is an expression which is used in a constant-expression context.
3300 For instance, it could be a VAR_DECL with a constant initializer.
3301 Extract the innest constant expression.
3303 This is basically a more powerful version of
3304 integral_constant_value, which can be used also in templates where
3305 initializers can maintain a syntactic rather than semantic form
3306 (even if they are non-dependent, for access-checking purposes). */
3309 fold_decl_constant_value (tree expr)
3311 tree const_expr = expr;
3314 expr = fold_non_dependent_expr (const_expr);
3315 const_expr = integral_constant_value (expr);
3317 while (expr != const_expr);
3322 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3323 must be a function or a pointer-to-function type, as specified
3324 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3325 and check that the resulting function has external linkage. */
3328 convert_nontype_argument_function (tree type, tree expr)
3333 fn = instantiate_type (type, fns, tf_none);
3334 if (fn == error_mark_node)
3335 return error_mark_node;
3338 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3339 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3341 /* [temp.arg.nontype]/1
3343 A template-argument for a non-type, non-template template-parameter
3346 -- the address of an object or function with external linkage. */
3347 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3349 error ("%qE is not a valid template argument for type %qT "
3350 "because function %qD has not external linkage",
3351 expr, type, fn_no_ptr);
3358 /* Attempt to convert the non-type template parameter EXPR to the
3359 indicated TYPE. If the conversion is successful, return the
3360 converted value. If the conversion is unsuccessful, return
3361 NULL_TREE if we issued an error message, or error_mark_node if we
3362 did not. We issue error messages for out-and-out bad template
3363 parameters, but not simply because the conversion failed, since we
3364 might be just trying to do argument deduction. Both TYPE and EXPR
3365 must be non-dependent.
3367 The conversion follows the special rules described in
3368 [temp.arg.nontype], and it is much more strict than an implicit
3371 This function is called twice for each template argument (see
3372 lookup_template_class for a more accurate description of this
3373 problem). This means that we need to handle expressions which
3374 are not valid in a C++ source, but can be created from the
3375 first call (for instance, casts to perform conversions). These
3376 hacks can go away after we fix the double coercion problem. */
3379 convert_nontype_argument (tree type, tree expr)
3383 /* Detect immediately string literals as invalid non-type argument.
3384 This special-case is not needed for correctness (we would easily
3385 catch this later), but only to provide better diagnostic for this
3386 common user mistake. As suggested by DR 100, we do not mention
3387 linkage issues in the diagnostic as this is not the point. */
3388 if (TREE_CODE (expr) == STRING_CST)
3390 error ("%qE is not a valid template argument for type %qT "
3391 "because string literals can never be used in this context",
3396 /* If we are in a template, EXPR may be non-dependent, but still
3397 have a syntactic, rather than semantic, form. For example, EXPR
3398 might be a SCOPE_REF, rather than the VAR_DECL to which the
3399 SCOPE_REF refers. Preserving the qualifying scope is necessary
3400 so that access checking can be performed when the template is
3401 instantiated -- but here we need the resolved form so that we can
3402 convert the argument. */
3403 expr = fold_non_dependent_expr (expr);
3404 expr_type = TREE_TYPE (expr);
3406 /* HACK: Due to double coercion, we can get a
3407 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3408 which is the tree that we built on the first call (see
3409 below when coercing to reference to object or to reference to
3410 function). We just strip everything and get to the arg.
3411 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3413 if (TREE_CODE (expr) == NOP_EXPR)
3415 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3417 /* ??? Maybe we could use convert_from_reference here, but we
3418 would need to relax its constraints because the NOP_EXPR
3419 could actually change the type to something more cv-qualified,
3420 and this is not folded by convert_from_reference. */
3421 tree addr = TREE_OPERAND (expr, 0);
3422 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3423 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3424 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3425 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3426 (TREE_TYPE (expr_type),
3427 TREE_TYPE (TREE_TYPE (addr))));
3429 expr = TREE_OPERAND (addr, 0);
3430 expr_type = TREE_TYPE (expr);
3433 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3434 parameter is a pointer to object, through decay and
3435 qualification conversion. Let's strip everything. */
3436 else if (TYPE_PTROBV_P (type))
3439 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3440 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3441 /* Skip the ADDR_EXPR only if it is part of the decay for
3442 an array. Otherwise, it is part of the original argument
3443 in the source code. */
3444 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3445 expr = TREE_OPERAND (expr, 0);
3446 expr_type = TREE_TYPE (expr);
3450 /* [temp.arg.nontype]/5, bullet 1
3452 For a non-type template-parameter of integral or enumeration type,
3453 integral promotions (_conv.prom_) and integral conversions
3454 (_conv.integral_) are applied. */
3455 if (INTEGRAL_TYPE_P (type))
3457 if (!INTEGRAL_TYPE_P (expr_type))
3458 return error_mark_node;
3460 expr = fold_decl_constant_value (expr);
3461 /* Notice that there are constant expressions like '4 % 0' which
3462 do not fold into integer constants. */
3463 if (TREE_CODE (expr) != INTEGER_CST)
3465 error ("%qE is not a valid template argument for type %qT "
3466 "because it is a non-constant expression", expr, type);
3470 /* At this point, an implicit conversion does what we want,
3471 because we already know that the expression is of integral
3473 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3474 if (expr == error_mark_node)
3475 return error_mark_node;
3477 /* Conversion was allowed: fold it to a bare integer constant. */
3480 /* [temp.arg.nontype]/5, bullet 2
3482 For a non-type template-parameter of type pointer to object,
3483 qualification conversions (_conv.qual_) and the array-to-pointer
3484 conversion (_conv.array_) are applied. */
3485 else if (TYPE_PTROBV_P (type))
3487 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3489 A template-argument for a non-type, non-template template-parameter
3490 shall be one of: [...]
3492 -- the name of a non-type template-parameter;
3493 -- the address of an object or function with external linkage, [...]
3494 expressed as "& id-expression" where the & is optional if the name
3495 refers to a function or array, or if the corresponding
3496 template-parameter is a reference.
3498 Here, we do not care about functions, as they are invalid anyway
3499 for a parameter of type pointer-to-object. */
3500 bool constant_address_p =
3501 (TREE_CODE (expr) == ADDR_EXPR
3502 || TREE_CODE (expr_type) == ARRAY_TYPE
3503 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3505 expr = decay_conversion (expr);
3506 if (expr == error_mark_node)
3507 return error_mark_node;
3509 expr = perform_qualification_conversions (type, expr);
3510 if (expr == error_mark_node)
3511 return error_mark_node;
3513 if (!constant_address_p)
3515 error ("%qE is not a valid template argument for type %qT "
3516 "because it is not a constant pointer", expr, type);
3520 /* [temp.arg.nontype]/5, bullet 3
3522 For a non-type template-parameter of type reference to object, no
3523 conversions apply. The type referred to by the reference may be more
3524 cv-qualified than the (otherwise identical) type of the
3525 template-argument. The template-parameter is bound directly to the
3526 template-argument, which must be an lvalue. */
3527 else if (TYPE_REF_OBJ_P (type))
3529 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3531 return error_mark_node;
3533 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3535 error ("%qE is not a valid template argument for type %qT "
3536 "because of conflicts in cv-qualification", expr, type);
3540 if (!real_lvalue_p (expr))
3542 error ("%qE is not a valid template argument for type %qT "
3543 "because it is not a lvalue", expr, type);
3547 /* [temp.arg.nontype]/1
3549 A template-argument for a non-type, non-template template-parameter
3550 shall be one of: [...]
3552 -- the address of an object or function with external linkage. */
3553 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3555 error ("%qE is not a valid template argument for type %qT "
3556 "because object %qD has not external linkage",
3561 expr = build_nop (type, build_address (expr));
3563 /* [temp.arg.nontype]/5, bullet 4
3565 For a non-type template-parameter of type pointer to function, only
3566 the function-to-pointer conversion (_conv.func_) is applied. If the
3567 template-argument represents a set of overloaded functions (or a
3568 pointer to such), the matching function is selected from the set
3570 else if (TYPE_PTRFN_P (type))
3572 /* If the argument is a template-id, we might not have enough
3573 context information to decay the pointer.
3574 ??? Why static5.C requires decay and subst1.C works fine
3576 if (!type_unknown_p (expr_type))
3578 expr = decay_conversion (expr);
3579 if (expr == error_mark_node)
3580 return error_mark_node;
3583 expr = convert_nontype_argument_function (type, expr);
3584 if (!expr || expr == error_mark_node)
3587 /* [temp.arg.nontype]/5, bullet 5
3589 For a non-type template-parameter of type reference to function, no
3590 conversions apply. If the template-argument represents a set of
3591 overloaded functions, the matching function is selected from the set
3593 else if (TYPE_REFFN_P (type))
3595 if (TREE_CODE (expr) == ADDR_EXPR)
3597 error ("%qE is not a valid template argument for type %qT "
3598 "because it is a pointer", expr, type);
3599 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3603 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3604 if (!expr || expr == error_mark_node)
3607 expr = build_nop (type, build_address (expr));
3609 /* [temp.arg.nontype]/5, bullet 6
3611 For a non-type template-parameter of type pointer to member function,
3612 no conversions apply. If the template-argument represents a set of
3613 overloaded member functions, the matching member function is selected
3614 from the set (_over.over_). */
3615 else if (TYPE_PTRMEMFUNC_P (type))
3617 expr = instantiate_type (type, expr, tf_none);
3618 if (expr == error_mark_node)
3619 return error_mark_node;
3621 /* There is no way to disable standard conversions in
3622 resolve_address_of_overloaded_function (called by
3623 instantiate_type). It is possible that the call succeeded by
3624 converting &B::I to &D::I (where B is a base of D), so we need
3625 to reject this conversion here.
3627 Actually, even if there was a way to disable standard conversions,
3628 it would still be better to reject them here so that we can
3629 provide a superior diagnostic. */
3630 if (!same_type_p (TREE_TYPE (expr), type))
3632 /* Make sure we are just one standard conversion off. */
3633 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3634 error ("%qE is not a valid template argument for type %qT "
3635 "because it is of type %qT", expr, type,
3637 inform ("standard conversions are not allowed in this context");
3641 /* [temp.arg.nontype]/5, bullet 7
3643 For a non-type template-parameter of type pointer to data member,
3644 qualification conversions (_conv.qual_) are applied. */
3645 else if (TYPE_PTRMEM_P (type))
3647 expr = perform_qualification_conversions (type, expr);
3648 if (expr == error_mark_node)
3651 /* A template non-type parameter must be one of the above. */
3655 /* Sanity check: did we actually convert the argument to the
3657 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3662 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3663 template template parameters. Both PARM_PARMS and ARG_PARMS are
3664 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3667 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3668 the case, then extra parameters must have default arguments.
3670 Consider the example:
3671 template <class T, class Allocator = allocator> class vector;
3672 template<template <class U> class TT> class C;
3674 C<vector> is a valid instantiation. PARM_PARMS for the above code
3675 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3676 T and Allocator) and OUTER_ARGS contains the argument that is used to
3677 substitute the TT parameter. */
3680 coerce_template_template_parms (tree parm_parms,
3682 tsubst_flags_t complain,
3686 int nparms, nargs, i;
3689 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3690 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3692 nparms = TREE_VEC_LENGTH (parm_parms);
3693 nargs = TREE_VEC_LENGTH (arg_parms);
3695 /* The rule here is opposite of coerce_template_parms. */
3698 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3701 for (i = 0; i < nparms; ++i)
3703 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3704 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3706 if (arg == NULL_TREE || arg == error_mark_node
3707 || parm == NULL_TREE || parm == error_mark_node)
3710 if (TREE_CODE (arg) != TREE_CODE (parm))
3713 switch (TREE_CODE (parm))
3719 /* We encounter instantiations of templates like
3720 template <template <template <class> class> class TT>
3723 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3724 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3726 if (!coerce_template_template_parms
3727 (parmparm, argparm, complain, in_decl, outer_args))
3733 /* The tsubst call is used to handle cases such as
3735 template <int> class C {};
3736 template <class T, template <T> class TT> class D {};
3739 i.e. the parameter list of TT depends on earlier parameters. */
3740 if (!dependent_type_p (TREE_TYPE (arg))
3742 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3754 /* Convert the indicated template ARG as necessary to match the
3755 indicated template PARM. Returns the converted ARG, or
3756 error_mark_node if the conversion was unsuccessful. Error and
3757 warning messages are issued under control of COMPLAIN. This
3758 conversion is for the Ith parameter in the parameter list. ARGS is
3759 the full set of template arguments deduced so far. */
3762 convert_template_argument (tree parm,
3765 tsubst_flags_t complain,
3771 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3773 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3775 if (TREE_CODE (arg) == TREE_LIST
3776 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3778 /* The template argument was the name of some
3779 member function. That's usually
3780 invalid, but static members are OK. In any
3781 case, grab the underlying fields/functions
3782 and issue an error later if required. */
3783 arg = TREE_VALUE (arg);
3784 TREE_TYPE (arg) = unknown_type_node;
3787 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3788 requires_type = (TREE_CODE (parm) == TYPE_DECL
3789 || requires_tmpl_type);
3791 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3792 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3793 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3794 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3797 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3798 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3799 arg = TYPE_STUB_DECL (arg);
3801 is_type = TYPE_P (arg) || is_tmpl_type;
3803 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3804 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3806 pedwarn ("to refer to a type member of a template parameter, "
3807 "use %<typename %E%>", arg);
3809 arg = make_typename_type (TREE_OPERAND (arg, 0),
3810 TREE_OPERAND (arg, 1),
3812 complain & tf_error);
3815 if (is_type != requires_type)
3819 if (complain & tf_error)
3821 error ("type/value mismatch at argument %d in template "
3822 "parameter list for %qD",
3825 error (" expected a constant of type %qT, got %qT",
3827 (is_tmpl_type ? DECL_NAME (arg) : arg));
3828 else if (requires_tmpl_type)
3829 error (" expected a class template, got %qE", arg);
3831 error (" expected a type, got %qE", arg);
3834 return error_mark_node;
3836 if (is_tmpl_type ^ requires_tmpl_type)
3838 if (in_decl && (complain & tf_error))
3840 error ("type/value mismatch at argument %d in template "
3841 "parameter list for %qD",
3844 error (" expected a type, got %qT", DECL_NAME (arg));
3846 error (" expected a class template, got %qT", arg);
3848 return error_mark_node;
3853 if (requires_tmpl_type)
3855 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3856 /* The number of argument required is not known yet.
3857 Just accept it for now. */
3858 val = TREE_TYPE (arg);
3861 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3862 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3864 if (coerce_template_template_parms (parmparm, argparm,
3870 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3872 if (val != error_mark_node
3873 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3874 val = TREE_TYPE (val);
3878 if (in_decl && (complain & tf_error))
3880 error ("type/value mismatch at argument %d in "
3881 "template parameter list for %qD",
3883 error (" expected a template of type %qD, got %qD",
3887 val = error_mark_node;
3896 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3898 if (invalid_nontype_parm_type_p (t, complain))
3899 return error_mark_node;
3901 if (!uses_template_parms (arg) && !uses_template_parms (t))
3902 /* We used to call digest_init here. However, digest_init
3903 will report errors, which we don't want when complain
3904 is zero. More importantly, digest_init will try too
3905 hard to convert things: for example, `0' should not be
3906 converted to pointer type at this point according to
3907 the standard. Accepting this is not merely an
3908 extension, since deciding whether or not these
3909 conversions can occur is part of determining which
3910 function template to call, or whether a given explicit
3911 argument specification is valid. */
3912 val = convert_nontype_argument (t, arg);
3916 if (val == NULL_TREE)
3917 val = error_mark_node;
3918 else if (val == error_mark_node && (complain & tf_error))
3919 error ("could not convert template argument %qE to %qT", arg, t);
3925 /* Convert all template arguments to their appropriate types, and
3926 return a vector containing the innermost resulting template
3927 arguments. If any error occurs, return error_mark_node. Error and
3928 warning messages are issued under control of COMPLAIN.
3930 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3931 provided in ARGLIST, or else trailing parameters must have default
3932 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3933 deduction for any unspecified trailing arguments. */
3936 coerce_template_parms (tree parms,
3939 tsubst_flags_t complain,
3940 int require_all_arguments)
3942 int nparms, nargs, i, lost = 0;
3945 tree new_inner_args;
3947 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3948 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3949 nparms = TREE_VEC_LENGTH (parms);
3953 && require_all_arguments
3954 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3956 if (complain & tf_error)
3958 error ("wrong number of template arguments (%d, should be %d)",
3962 error ("provided for %q+D", in_decl);
3965 return error_mark_node;
3968 new_inner_args = make_tree_vec (nparms);
3969 new_args = add_outermost_template_args (args, new_inner_args);
3970 for (i = 0; i < nparms; i++)
3975 /* Get the Ith template parameter. */
3976 parm = TREE_VEC_ELT (parms, i);
3978 /* Calculate the Ith argument. */
3980 arg = TREE_VEC_ELT (inner_args, i);
3981 else if (require_all_arguments)
3982 /* There must be a default arg in this case. */
3983 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
3989 if (arg == error_mark_node)
3991 if (complain & tf_error)
3992 error ("template argument %d is invalid", i + 1);
3995 arg = convert_template_argument (TREE_VALUE (parm),
3996 arg, new_args, complain, i,
3999 if (arg == error_mark_node)
4001 TREE_VEC_ELT (new_inner_args, i) = arg;
4005 return error_mark_node;
4007 return new_inner_args;
4010 /* Returns 1 if template args OT and NT are equivalent. */
4013 template_args_equal (tree ot, tree nt)
4018 if (TREE_CODE (nt) == TREE_VEC)
4019 /* For member templates */
4020 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4021 else if (TYPE_P (nt))
4022 return TYPE_P (ot) && same_type_p (ot, nt);
4023 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4026 return cp_tree_equal (ot, nt);
4029 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4030 of template arguments. Returns 0 otherwise. */
4033 comp_template_args (tree oldargs, tree newargs)
4037 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4040 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4042 tree nt = TREE_VEC_ELT (newargs, i);
4043 tree ot = TREE_VEC_ELT (oldargs, i);
4045 if (! template_args_equal (ot, nt))
4051 /* Given class template name and parameter list, produce a user-friendly name
4052 for the instantiation. */
4055 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4057 static struct obstack scratch_obstack;
4058 static char *scratch_firstobj;
4061 if (!scratch_firstobj)
4062 gcc_obstack_init (&scratch_obstack);
4064 obstack_free (&scratch_obstack, scratch_firstobj);
4065 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4067 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4068 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4072 nparms = TREE_VEC_LENGTH (parms);
4073 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4074 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4075 for (i = 0; i < nparms; i++)
4077 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4078 tree arg = TREE_VEC_ELT (arglist, i);
4083 if (TREE_CODE (parm) == TYPE_DECL)
4085 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4088 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4090 if (TREE_CODE (arg) == TEMPLATE_DECL)
4092 /* Already substituted with real template. Just output
4093 the template name here */
4094 tree context = DECL_CONTEXT (arg);
4097 /* The template may be defined in a namespace, or
4098 may be a member template. */
4099 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4100 || CLASS_TYPE_P (context));
4101 cat (decl_as_string (DECL_CONTEXT (arg),
4102 TFF_PLAIN_IDENTIFIER));
4105 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4108 /* Output the parameter declaration. */
4109 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4113 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4115 /* No need to check arglist against parmlist here; we did that
4116 in coerce_template_parms, called from lookup_template_class. */
4117 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4120 char *bufp = obstack_next_free (&scratch_obstack);
4122 while (bufp[offset - 1] == ' ')
4124 obstack_blank_fast (&scratch_obstack, offset);
4126 /* B<C<char> >, not B<C<char>> */
4127 if (bufp[offset - 1] == '>')
4132 return (char *) obstack_base (&scratch_obstack);
4136 classtype_mangled_name (tree t)
4138 if (CLASSTYPE_TEMPLATE_INFO (t)
4139 /* Specializations have already had their names set up in
4140 lookup_template_class. */
4141 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4143 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4145 /* For non-primary templates, the template parameters are
4146 implicit from their surrounding context. */
4147 if (PRIMARY_TEMPLATE_P (tmpl))
4149 tree name = DECL_NAME (tmpl);
4150 char *mangled_name = mangle_class_name_for_template
4151 (IDENTIFIER_POINTER (name),
4152 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4153 CLASSTYPE_TI_ARGS (t));
4154 tree id = get_identifier (mangled_name);
4155 IDENTIFIER_TEMPLATE (id) = name;
4160 return TYPE_IDENTIFIER (t);
4164 add_pending_template (tree d)
4166 tree ti = (TYPE_P (d)
4167 ? CLASSTYPE_TEMPLATE_INFO (d)
4168 : DECL_TEMPLATE_INFO (d));
4172 if (TI_PENDING_TEMPLATE_FLAG (ti))
4175 /* We are called both from instantiate_decl, where we've already had a
4176 tinst_level pushed, and instantiate_template, where we haven't.
4178 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4181 push_tinst_level (d);
4183 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4184 if (last_pending_template)
4185 TREE_CHAIN (last_pending_template) = pt;
4187 pending_templates = pt;
4189 last_pending_template = pt;
4191 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4198 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4199 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4200 documentation for TEMPLATE_ID_EXPR. */
4203 lookup_template_function (tree fns, tree arglist)
4207 if (fns == error_mark_node || arglist == error_mark_node)
4208 return error_mark_node;
4210 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4211 gcc_assert (fns && (is_overloaded_fn (fns)
4212 || TREE_CODE (fns) == IDENTIFIER_NODE));
4214 if (BASELINK_P (fns))
4216 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4218 BASELINK_FUNCTIONS (fns),
4223 type = TREE_TYPE (fns);
4224 if (TREE_CODE (fns) == OVERLOAD || !type)
4225 type = unknown_type_node;
4227 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4230 /* Within the scope of a template class S<T>, the name S gets bound
4231 (in build_self_reference) to a TYPE_DECL for the class, not a
4232 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4233 or one of its enclosing classes, and that type is a template,
4234 return the associated TEMPLATE_DECL. Otherwise, the original
4235 DECL is returned. */
4238 maybe_get_template_decl_from_type_decl (tree decl)
4240 return (decl != NULL_TREE
4241 && TREE_CODE (decl) == TYPE_DECL
4242 && DECL_ARTIFICIAL (decl)
4243 && CLASS_TYPE_P (TREE_TYPE (decl))
4244 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4245 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4248 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4249 parameters, find the desired type.
4251 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4253 IN_DECL, if non-NULL, is the template declaration we are trying to
4256 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4257 the class we are looking up.
4259 Issue error and warning messages under control of COMPLAIN.
4261 If the template class is really a local class in a template
4262 function, then the FUNCTION_CONTEXT is the function in which it is
4265 ??? Note that this function is currently called *twice* for each
4266 template-id: the first time from the parser, while creating the
4267 incomplete type (finish_template_type), and the second type during the
4268 real instantiation (instantiate_template_class). This is surely something
4269 that we want to avoid. It also causes some problems with argument
4270 coercion (see convert_nontype_argument for more information on this). */
4273 lookup_template_class (tree d1,
4278 tsubst_flags_t complain)
4280 tree template = NULL_TREE, parmlist;
4283 timevar_push (TV_NAME_LOOKUP);
4285 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4287 tree value = innermost_non_namespace_value (d1);
4288 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4293 push_decl_namespace (context);
4294 template = lookup_name (d1, /*prefer_type=*/0);
4295 template = maybe_get_template_decl_from_type_decl (template);
4297 pop_decl_namespace ();
4300 context = DECL_CONTEXT (template);
4302 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4304 tree type = TREE_TYPE (d1);
4306 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4307 an implicit typename for the second A. Deal with it. */
4308 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4309 type = TREE_TYPE (type);
4311 if (CLASSTYPE_TEMPLATE_INFO (type))
4313 template = CLASSTYPE_TI_TEMPLATE (type);
4314 d1 = DECL_NAME (template);
4317 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4318 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4320 template = TYPE_TI_TEMPLATE (d1);
4321 d1 = DECL_NAME (template);
4323 else if (TREE_CODE (d1) == TEMPLATE_DECL
4324 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4327 d1 = DECL_NAME (template);
4328 context = DECL_CONTEXT (template);
4331 /* Issue an error message if we didn't find a template. */
4334 if (complain & tf_error)
4335 error ("%qT is not a template", d1);
4336 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4339 if (TREE_CODE (template) != TEMPLATE_DECL
4340 /* Make sure it's a user visible template, if it was named by
4342 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4343 && !PRIMARY_TEMPLATE_P (template)))
4345 if (complain & tf_error)
4347 error ("non-template type %qT used as a template", d1);
4349 error ("for template declaration %q+D", in_decl);
4351 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4354 complain &= ~tf_user;
4356 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4358 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4359 template arguments */
4364 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4366 /* Consider an example where a template template parameter declared as
4368 template <class T, class U = std::allocator<T> > class TT
4370 The template parameter level of T and U are one level larger than
4371 of TT. To proper process the default argument of U, say when an
4372 instantiation `TT<int>' is seen, we need to build the full
4373 arguments containing {int} as the innermost level. Outer levels,
4374 available when not appearing as default template argument, can be
4375 obtained from `current_template_args ()'.
4377 Suppose that TT is later substituted with std::vector. The above
4378 instantiation is `TT<int, std::allocator<T> >' with TT at
4379 level 1, and T at level 2, while the template arguments at level 1
4380 becomes {std::vector} and the inner level 2 is {int}. */
4382 if (current_template_parms)
4383 arglist = add_to_template_args (current_template_args (), arglist);
4385 arglist2 = coerce_template_parms (parmlist, arglist, template,
4386 complain, /*require_all_args=*/1);
4387 if (arglist2 == error_mark_node
4388 || (!uses_template_parms (arglist2)
4389 && check_instantiated_args (template, arglist2, complain)))
4390 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4392 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4393 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4397 tree template_type = TREE_TYPE (template);
4400 tree found = NULL_TREE;
4403 int is_partial_instantiation;
4405 gen_tmpl = most_general_template (template);
4406 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4407 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4408 arg_depth = TMPL_ARGS_DEPTH (arglist);
4410 if (arg_depth == 1 && parm_depth > 1)
4412 /* We've been given an incomplete set of template arguments.
4415 template <class T> struct S1 {
4416 template <class U> struct S2 {};
4417 template <class U> struct S2<U*> {};
4420 we will be called with an ARGLIST of `U*', but the
4421 TEMPLATE will be `template <class T> template
4422 <class U> struct S1<T>::S2'. We must fill in the missing
4425 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4427 arg_depth = TMPL_ARGS_DEPTH (arglist);
4430 /* Now we should have enough arguments. */
4431 gcc_assert (parm_depth == arg_depth);
4433 /* From here on, we're only interested in the most general
4435 template = gen_tmpl;
4437 /* Calculate the BOUND_ARGS. These will be the args that are
4438 actually tsubst'd into the definition to create the
4442 /* We have multiple levels of arguments to coerce, at once. */
4444 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4446 tree bound_args = make_tree_vec (parm_depth);
4448 for (i = saved_depth,
4449 t = DECL_TEMPLATE_PARMS (template);
4450 i > 0 && t != NULL_TREE;
4451 --i, t = TREE_CHAIN (t))
4453 tree a = coerce_template_parms (TREE_VALUE (t),
4455 complain, /*require_all_args=*/1);
4457 /* Don't process further if one of the levels fails. */
4458 if (a == error_mark_node)
4460 /* Restore the ARGLIST to its full size. */
4461 TREE_VEC_LENGTH (arglist) = saved_depth;
4462 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4465 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4467 /* We temporarily reduce the length of the ARGLIST so
4468 that coerce_template_parms will see only the arguments
4469 corresponding to the template parameters it is
4471 TREE_VEC_LENGTH (arglist)--;
4474 /* Restore the ARGLIST to its full size. */
4475 TREE_VEC_LENGTH (arglist) = saved_depth;
4477 arglist = bound_args;
4481 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4482 INNERMOST_TEMPLATE_ARGS (arglist),
4484 complain, /*require_all_args=*/1);
4486 if (arglist == error_mark_node)
4487 /* We were unable to bind the arguments. */
4488 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4490 /* In the scope of a template class, explicit references to the
4491 template class refer to the type of the template, not any
4492 instantiation of it. For example, in:
4494 template <class T> class C { void f(C<T>); }
4496 the `C<T>' is just the same as `C'. Outside of the
4497 class, however, such a reference is an instantiation. */
4498 if (comp_template_args (TYPE_TI_ARGS (template_type),
4501 found = template_type;
4503 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4507 for (ctx = current_class_type;
4508 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4510 ? TYPE_CONTEXT (ctx)
4511 : DECL_CONTEXT (ctx)))
4512 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4515 /* We're not in the scope of the class, so the
4516 TEMPLATE_TYPE is not the type we want after all. */
4522 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4524 /* If we already have this specialization, return it. */
4525 found = retrieve_specialization (template, arglist,
4526 /*class_specializations_p=*/false);
4528 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4530 /* This type is a "partial instantiation" if any of the template
4531 arguments still involve template parameters. Note that we set
4532 IS_PARTIAL_INSTANTIATION for partial specializations as
4534 is_partial_instantiation = uses_template_parms (arglist);
4536 /* If the deduced arguments are invalid, then the binding
4538 if (!is_partial_instantiation
4539 && check_instantiated_args (template,
4540 INNERMOST_TEMPLATE_ARGS (arglist),
4542 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4544 if (!is_partial_instantiation
4545 && !PRIMARY_TEMPLATE_P (template)
4546 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4548 found = xref_tag_from_type (TREE_TYPE (template),
4549 DECL_NAME (template),
4550 /*tag_scope=*/ts_global);
4551 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4554 context = tsubst (DECL_CONTEXT (template), arglist,
4557 context = global_namespace;
4559 /* Create the type. */
4560 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4562 if (!is_partial_instantiation)
4564 set_current_access_from_decl (TYPE_NAME (template_type));
4565 t = start_enum (TYPE_IDENTIFIER (template_type));
4568 /* We don't want to call start_enum for this type, since
4569 the values for the enumeration constants may involve
4570 template parameters. And, no one should be interested
4571 in the enumeration constants for such a type. */
4572 t = make_node (ENUMERAL_TYPE);
4576 t = make_aggr_type (TREE_CODE (template_type));
4577 CLASSTYPE_DECLARED_CLASS (t)
4578 = CLASSTYPE_DECLARED_CLASS (template_type);
4579 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4580 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4582 /* A local class. Make sure the decl gets registered properly. */
4583 if (context == current_function_decl)
4584 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
4587 /* If we called start_enum or pushtag above, this information
4588 will already be set up. */
4591 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4593 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4594 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4595 TYPE_STUB_DECL (t) = type_decl;
4596 DECL_SOURCE_LOCATION (type_decl)
4597 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4600 type_decl = TYPE_NAME (t);
4602 TREE_PRIVATE (type_decl)
4603 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4604 TREE_PROTECTED (type_decl)
4605 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4606 DECL_IN_SYSTEM_HEADER (type_decl)
4607 = DECL_IN_SYSTEM_HEADER (template);
4609 /* Set up the template information. We have to figure out which
4610 template is the immediate parent if this is a full
4612 if (parm_depth == 1 || is_partial_instantiation
4613 || !PRIMARY_TEMPLATE_P (template))
4614 /* This case is easy; there are no member templates involved. */
4618 /* This is a full instantiation of a member template. Look
4619 for a partial instantiation of which this is an instance. */
4621 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4622 found; found = TREE_CHAIN (found))
4625 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4627 /* We only want partial instantiations, here, not
4628 specializations or full instantiations. */
4629 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4630 || !uses_template_parms (TREE_VALUE (found)))
4633 /* Temporarily reduce by one the number of levels in the
4634 ARGLIST and in FOUND so as to avoid comparing the
4635 last set of arguments. */
4636 TREE_VEC_LENGTH (arglist)--;
4637 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4639 /* See if the arguments match. If they do, then TMPL is
4640 the partial instantiation we want. */
4641 success = comp_template_args (TREE_PURPOSE (found), arglist);
4643 /* Restore the argument vectors to their full size. */
4644 TREE_VEC_LENGTH (arglist)++;
4645 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4656 /* There was no partial instantiation. This happens
4657 where C<T> is a member template of A<T> and it's used
4660 template <typename T> struct B { A<T>::C<int> m; };
4663 Create the partial instantiation.
4665 TREE_VEC_LENGTH (arglist)--;
4666 found = tsubst (template, arglist, complain, NULL_TREE);
4667 TREE_VEC_LENGTH (arglist)++;
4671 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4672 DECL_TEMPLATE_INSTANTIATIONS (template)
4673 = tree_cons (arglist, t,
4674 DECL_TEMPLATE_INSTANTIATIONS (template));
4676 if (TREE_CODE (t) == ENUMERAL_TYPE
4677 && !is_partial_instantiation)
4678 /* Now that the type has been registered on the instantiations
4679 list, we set up the enumerators. Because the enumeration
4680 constants may involve the enumeration type itself, we make
4681 sure to register the type first, and then create the
4682 constants. That way, doing tsubst_expr for the enumeration
4683 constants won't result in recursive calls here; we'll find
4684 the instantiation and exit above. */
4685 tsubst_enum (template_type, t, arglist);
4687 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4689 if (TREE_CODE (t) != ENUMERAL_TYPE)
4690 DECL_NAME (type_decl) = classtype_mangled_name (t);
4691 if (is_partial_instantiation)
4692 /* If the type makes use of template parameters, the
4693 code that generates debugging information will crash. */
4694 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4696 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4698 timevar_pop (TV_NAME_LOOKUP);
4705 struct pointer_set_t *visited;
4708 /* Called from for_each_template_parm via walk_tree. */
4711 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4714 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4715 tree_fn_t fn = pfd->fn;
4716 void *data = pfd->data;
4719 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4720 return error_mark_node;
4722 switch (TREE_CODE (t))
4725 if (TYPE_PTRMEMFUNC_P (t))
4731 if (!TYPE_TEMPLATE_INFO (t))
4733 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4734 fn, data, pfd->visited))
4735 return error_mark_node;
4739 /* Since we're not going to walk subtrees, we have to do this
4741 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4743 return error_mark_node;
4747 /* Check the return type. */
4748 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4749 return error_mark_node;
4751 /* Check the parameter types. Since default arguments are not
4752 instantiated until they are needed, the TYPE_ARG_TYPES may
4753 contain expressions that involve template parameters. But,
4754 no-one should be looking at them yet. And, once they're
4755 instantiated, they don't contain template parameters, so
4756 there's no point in looking at them then, either. */
4760 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4761 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4763 return error_mark_node;
4765 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4766 want walk_tree walking into them itself. */
4772 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4774 return error_mark_node;
4779 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4780 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4782 return error_mark_node;
4787 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4788 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4790 return error_mark_node;
4791 if (DECL_CONTEXT (t)
4792 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4794 return error_mark_node;
4797 case BOUND_TEMPLATE_TEMPLATE_PARM:
4798 /* Record template parameters such as `T' inside `TT<T>'. */
4799 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4800 return error_mark_node;
4803 case TEMPLATE_TEMPLATE_PARM:
4804 case TEMPLATE_TYPE_PARM:
4805 case TEMPLATE_PARM_INDEX:
4806 if (fn && (*fn)(t, data))
4807 return error_mark_node;
4809 return error_mark_node;
4813 /* A template template parameter is encountered. */
4814 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4815 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4816 return error_mark_node;
4818 /* Already substituted template template parameter */
4824 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4825 data, pfd->visited))
4826 return error_mark_node;
4830 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4831 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4832 (TREE_TYPE (t)), fn, data,
4834 return error_mark_node;
4839 /* If there's no type, then this thing must be some expression
4840 involving template parameters. */
4841 if (!fn && !TREE_TYPE (t))
4842 return error_mark_node;
4847 case REINTERPRET_CAST_EXPR:
4848 case CONST_CAST_EXPR:
4849 case STATIC_CAST_EXPR:
4850 case DYNAMIC_CAST_EXPR:
4854 case PSEUDO_DTOR_EXPR:
4856 return error_mark_node;
4860 /* If we do not handle this case specially, we end up walking
4861 the BINFO hierarchy, which is circular, and therefore
4862 confuses walk_tree. */
4864 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4866 return error_mark_node;
4873 /* We didn't find any template parameters we liked. */
4877 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4878 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4879 call FN with the parameter and the DATA.
4880 If FN returns nonzero, the iteration is terminated, and
4881 for_each_template_parm returns 1. Otherwise, the iteration
4882 continues. If FN never returns a nonzero value, the value
4883 returned by for_each_template_parm is 0. If FN is NULL, it is
4884 considered to be the function which always returns 1. */
4887 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4888 struct pointer_set_t *visited)
4890 struct pair_fn_data pfd;
4897 /* Walk the tree. (Conceptually, we would like to walk without
4898 duplicates, but for_each_template_parm_r recursively calls
4899 for_each_template_parm, so we would need to reorganize a fair
4900 bit to use walk_tree_without_duplicates, so we keep our own
4903 pfd.visited = visited;
4905 pfd.visited = pointer_set_create ();
4906 result = walk_tree (&t,
4907 for_each_template_parm_r,
4909 pfd.visited) != NULL_TREE;
4914 pointer_set_destroy (pfd.visited);
4921 /* Returns true if T depends on any template parameter. */
4924 uses_template_parms (tree t)
4927 int saved_processing_template_decl;
4929 saved_processing_template_decl = processing_template_decl;
4930 if (!saved_processing_template_decl)
4931 processing_template_decl = 1;
4933 dependent_p = dependent_type_p (t);
4934 else if (TREE_CODE (t) == TREE_VEC)
4935 dependent_p = any_dependent_template_arguments_p (t);
4936 else if (TREE_CODE (t) == TREE_LIST)
4937 dependent_p = (uses_template_parms (TREE_VALUE (t))
4938 || uses_template_parms (TREE_CHAIN (t)));
4941 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4942 || TREE_CODE (t) == OVERLOAD
4943 || TREE_CODE (t) == BASELINK
4944 || CONSTANT_CLASS_P (t))
4945 dependent_p = (type_dependent_expression_p (t)
4946 || value_dependent_expression_p (t));
4949 gcc_assert (t == error_mark_node);
4950 dependent_p = false;
4953 processing_template_decl = saved_processing_template_decl;
4958 /* Returns true if T depends on any template parameter with level LEVEL. */
4961 uses_template_parms_level (tree t, int level)
4963 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4966 static int tinst_depth;
4967 extern int max_tinst_depth;
4968 #ifdef GATHER_STATISTICS
4971 static int tinst_level_tick;
4972 static int last_template_error_tick;
4974 /* We're starting to instantiate D; record the template instantiation context
4975 for diagnostics and to restore it later. */
4978 push_tinst_level (tree d)
4982 if (tinst_depth >= max_tinst_depth)
4984 /* If the instantiation in question still has unbound template parms,
4985 we don't really care if we can't instantiate it, so just return.
4986 This happens with base instantiation for implicit `typename'. */
4987 if (uses_template_parms (d))
4990 last_template_error_tick = tinst_level_tick;
4991 error ("template instantiation depth exceeds maximum of %d (use "
4992 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
4993 max_tinst_depth, d);
4995 print_instantiation_context ();
5000 new = make_node (TINST_LEVEL);
5001 TINST_DECL (new) = d;
5002 TINST_LOCATION (new) = input_location;
5003 TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
5004 TREE_CHAIN (new) = current_tinst_level;
5005 current_tinst_level = new;
5008 #ifdef GATHER_STATISTICS
5009 if (tinst_depth > depth_reached)
5010 depth_reached = tinst_depth;
5017 /* We're done instantiating this template; return to the instantiation
5021 pop_tinst_level (void)
5023 tree old = current_tinst_level;
5025 /* Restore the filename and line number stashed away when we started
5026 this instantiation. */
5027 input_location = TINST_LOCATION (old);
5028 in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
5029 current_tinst_level = TREE_CHAIN (old);
5034 /* We're instantiating a deferred template; restore the template
5035 instantiation context in which the instantiation was requested, which
5036 is one step out from LEVEL. */
5039 reopen_tinst_level (tree level)
5044 for (t = level; t; t = TREE_CHAIN (t))
5047 current_tinst_level = level;
5051 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5052 vector of template arguments, as for tsubst.
5054 Returns an appropriate tsubst'd friend declaration. */
5057 tsubst_friend_function (tree decl, tree args)
5061 if (TREE_CODE (decl) == FUNCTION_DECL
5062 && DECL_TEMPLATE_INSTANTIATION (decl)
5063 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5064 /* This was a friend declared with an explicit template
5065 argument list, e.g.:
5069 to indicate that f was a template instantiation, not a new
5070 function declaration. Now, we have to figure out what
5071 instantiation of what template. */
5073 tree template_id, arglist, fns;
5076 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5078 /* Friend functions are looked up in the containing namespace scope.
5079 We must enter that scope, to avoid finding member functions of the
5080 current cless with same name. */
5081 push_nested_namespace (ns);
5082 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5083 tf_error | tf_warning, NULL_TREE);
5084 pop_nested_namespace (ns);
5085 arglist = tsubst (DECL_TI_ARGS (decl), args,
5086 tf_error | tf_warning, NULL_TREE);
5087 template_id = lookup_template_function (fns, arglist);
5089 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5090 tmpl = determine_specialization (template_id, new_friend,
5092 /*need_member_template=*/0,
5093 TREE_VEC_LENGTH (args));
5094 return instantiate_template (tmpl, new_args, tf_error);
5097 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5099 /* The NEW_FRIEND will look like an instantiation, to the
5100 compiler, but is not an instantiation from the point of view of
5101 the language. For example, we might have had:
5103 template <class T> struct S {
5104 template <class U> friend void f(T, U);
5107 Then, in S<int>, template <class U> void f(int, U) is not an
5108 instantiation of anything. */
5109 if (new_friend == error_mark_node)
5110 return error_mark_node;
5112 DECL_USE_TEMPLATE (new_friend) = 0;
5113 if (TREE_CODE (decl) == TEMPLATE_DECL)
5115 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5116 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5117 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5120 /* The mangled name for the NEW_FRIEND is incorrect. The function
5121 is not a template instantiation and should not be mangled like
5122 one. Therefore, we forget the mangling here; we'll recompute it
5123 later if we need it. */
5124 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5126 SET_DECL_RTL (new_friend, NULL_RTX);
5127 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5130 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5133 tree new_friend_template_info;
5134 tree new_friend_result_template_info;
5136 int new_friend_is_defn;
5138 /* We must save some information from NEW_FRIEND before calling
5139 duplicate decls since that function will free NEW_FRIEND if
5141 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5142 new_friend_is_defn =
5143 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5144 (template_for_substitution (new_friend)))
5146 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5148 /* This declaration is a `primary' template. */
5149 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5151 new_friend_result_template_info
5152 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5155 new_friend_result_template_info = NULL_TREE;
5157 /* Inside pushdecl_namespace_level, we will push into the
5158 current namespace. However, the friend function should go
5159 into the namespace of the template. */
5160 ns = decl_namespace_context (new_friend);
5161 push_nested_namespace (ns);
5162 old_decl = pushdecl_namespace_level (new_friend);
5163 pop_nested_namespace (ns);
5165 if (old_decl != new_friend)
5167 /* This new friend declaration matched an existing
5168 declaration. For example, given:
5170 template <class T> void f(T);
5171 template <class U> class C {
5172 template <class T> friend void f(T) {}
5175 the friend declaration actually provides the definition
5176 of `f', once C has been instantiated for some type. So,
5177 old_decl will be the out-of-class template declaration,
5178 while new_friend is the in-class definition.
5180 But, if `f' was called before this point, the
5181 instantiation of `f' will have DECL_TI_ARGS corresponding
5182 to `T' but not to `U', references to which might appear
5183 in the definition of `f'. Previously, the most general
5184 template for an instantiation of `f' was the out-of-class
5185 version; now it is the in-class version. Therefore, we
5186 run through all specialization of `f', adding to their
5187 DECL_TI_ARGS appropriately. In particular, they need a
5188 new set of outer arguments, corresponding to the
5189 arguments for this class instantiation.
5191 The same situation can arise with something like this:
5194 template <class T> class C {
5198 when `C<int>' is instantiated. Now, `f(int)' is defined
5201 if (!new_friend_is_defn)
5202 /* On the other hand, if the in-class declaration does
5203 *not* provide a definition, then we don't want to alter
5204 existing definitions. We can just leave everything
5209 /* Overwrite whatever template info was there before, if
5210 any, with the new template information pertaining to
5212 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5214 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5215 reregister_specialization (new_friend,
5216 most_general_template (old_decl),
5221 tree new_friend_args;
5223 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5224 = new_friend_result_template_info;
5226 new_friend_args = TI_ARGS (new_friend_template_info);
5227 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5231 tree spec = TREE_VALUE (t);
5234 = add_outermost_template_args (new_friend_args,
5235 DECL_TI_ARGS (spec));
5238 /* Now, since specializations are always supposed to
5239 hang off of the most general template, we must move
5241 t = most_general_template (old_decl);
5244 DECL_TEMPLATE_SPECIALIZATIONS (t)
5245 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5246 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5247 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5252 /* The information from NEW_FRIEND has been merged into OLD_DECL
5253 by duplicate_decls. */
5254 new_friend = old_decl;
5259 tree context = DECL_CONTEXT (new_friend);
5263 template <class T> class C {
5264 template <class U> friend void C1<U>::f (); // case 1
5265 friend void C2<T>::f (); // case 2
5267 we only need to make sure CONTEXT is a complete type for
5268 case 2. To distinguish between the two cases, we note that
5269 CONTEXT of case 1 remains dependent type after tsubst while
5270 this isn't true for case 2. */
5271 ++processing_template_decl;
5272 dependent_p = dependent_type_p (context);
5273 --processing_template_decl;
5276 && !complete_type_or_else (context, NULL_TREE))
5277 return error_mark_node;
5279 if (COMPLETE_TYPE_P (context))
5281 /* Check to see that the declaration is really present, and,
5282 possibly obtain an improved declaration. */
5283 tree fn = check_classfn (context,
5284 new_friend, NULL_TREE);
5294 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5295 template arguments, as for tsubst.
5297 Returns an appropriate tsubst'd friend type or error_mark_node on
5301 tsubst_friend_class (tree friend_tmpl, tree args)
5307 context = DECL_CONTEXT (friend_tmpl);
5311 if (TREE_CODE (context) == NAMESPACE_DECL)
5312 push_nested_namespace (context);
5314 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5317 /* First, we look for a class template. */
5318 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5320 /* But, if we don't find one, it might be because we're in a
5321 situation like this:
5329 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5330 for `S<int>', not the TEMPLATE_DECL. */
5331 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5333 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5334 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5337 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5339 /* The friend template has already been declared. Just
5340 check to see that the declarations match, and install any new
5341 default parameters. We must tsubst the default parameters,
5342 of course. We only need the innermost template parameters
5343 because that is all that redeclare_class_template will look
5345 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5346 > TMPL_ARGS_DEPTH (args))
5349 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5350 args, tf_error | tf_warning);
5351 redeclare_class_template (TREE_TYPE (tmpl), parms);
5354 friend_type = TREE_TYPE (tmpl);
5358 /* The friend template has not already been declared. In this
5359 case, the instantiation of the template class will cause the
5360 injection of this template into the global scope. */
5361 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5363 /* The new TMPL is not an instantiation of anything, so we
5364 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5365 the new type because that is supposed to be the corresponding
5366 template decl, i.e., TMPL. */
5367 DECL_USE_TEMPLATE (tmpl) = 0;
5368 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5369 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5370 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5371 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5373 /* Inject this template into the global scope. */
5374 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5379 if (TREE_CODE (context) == NAMESPACE_DECL)
5380 pop_nested_namespace (context);
5382 pop_nested_class ();
5388 /* Returns zero if TYPE cannot be completed later due to circularity.
5389 Otherwise returns one. */
5392 can_complete_type_without_circularity (tree type)
5394 if (type == NULL_TREE || type == error_mark_node)
5396 else if (COMPLETE_TYPE_P (type))
5398 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5399 return can_complete_type_without_circularity (TREE_TYPE (type));
5400 else if (CLASS_TYPE_P (type)
5401 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5408 instantiate_class_template (tree type)
5410 tree template, args, pattern, t, member;
5415 if (type == error_mark_node)
5416 return error_mark_node;
5418 if (TYPE_BEING_DEFINED (type)
5419 || COMPLETE_TYPE_P (type)
5420 || dependent_type_p (type))
5423 /* Figure out which template is being instantiated. */
5424 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5425 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5427 /* Figure out which arguments are being used to do the
5429 args = CLASSTYPE_TI_ARGS (type);
5431 /* Determine what specialization of the original template to
5433 t = most_specialized_class (template, args);
5434 if (t == error_mark_node)
5436 const char *str = "candidates are:";
5437 error ("ambiguous class template instantiation for %q#T", type);
5438 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5441 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5443 error ("%s %+#T", str, TREE_TYPE (t));
5447 TYPE_BEING_DEFINED (type) = 1;
5448 return error_mark_node;
5452 pattern = TREE_TYPE (t);
5454 pattern = TREE_TYPE (template);
5456 /* If the template we're instantiating is incomplete, then clearly
5457 there's nothing we can do. */
5458 if (!COMPLETE_TYPE_P (pattern))
5461 /* If we've recursively instantiated too many templates, stop. */
5462 if (! push_tinst_level (type))
5465 /* Now we're really doing the instantiation. Mark the type as in
5466 the process of being defined. */
5467 TYPE_BEING_DEFINED (type) = 1;
5469 /* We may be in the middle of deferred access check. Disable
5471 push_deferring_access_checks (dk_no_deferred);
5473 push_to_top_level ();
5477 /* This TYPE is actually an instantiation of a partial
5478 specialization. We replace the innermost set of ARGS with
5479 the arguments appropriate for substitution. For example,
5482 template <class T> struct S {};
5483 template <class T> struct S<T*> {};
5485 and supposing that we are instantiating S<int*>, ARGS will
5486 present be {int*} but we need {int}. */
5488 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5491 /* If there were multiple levels in ARGS, replacing the
5492 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5493 want, so we make a copy first. */
5494 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5496 args = copy_node (args);
5497 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5503 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5505 /* Set the input location to the template definition. This is needed
5506 if tsubsting causes an error. */
5507 typedecl = TYPE_MAIN_DECL (type);
5508 input_location = DECL_SOURCE_LOCATION (typedecl);
5509 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
5511 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5512 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5513 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5514 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5515 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5516 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5517 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5518 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5519 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5520 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5521 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5522 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5523 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5524 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5525 if (ANON_AGGR_TYPE_P (pattern))
5526 SET_ANON_AGGR_TYPE_P (type);
5528 pbinfo = TYPE_BINFO (pattern);
5530 /* We should never instantiate a nested class before its enclosing
5531 class; we need to look up the nested class by name before we can
5532 instantiate it, and that lookup should instantiate the enclosing
5534 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5535 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5536 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5538 base_list = NULL_TREE;
5539 if (BINFO_N_BASE_BINFOS (pbinfo))
5542 tree context = TYPE_CONTEXT (type);
5546 /* We must enter the scope containing the type, as that is where
5547 the accessibility of types named in dependent bases are
5549 pushed_scope = push_scope (context ? context : global_namespace);
5551 /* Substitute into each of the bases to determine the actual
5553 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5556 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5558 /* Substitute to figure out the base class. */
5559 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5560 if (base == error_mark_node)
5563 base_list = tree_cons (access, base, base_list);
5564 if (BINFO_VIRTUAL_P (pbase_binfo))
5565 TREE_TYPE (base_list) = integer_type_node;
5568 /* The list is now in reverse order; correct that. */
5569 base_list = nreverse (base_list);
5572 pop_scope (pushed_scope);
5574 /* Now call xref_basetypes to set up all the base-class
5576 xref_basetypes (type, base_list);
5579 /* Now that our base classes are set up, enter the scope of the
5580 class, so that name lookups into base classes, etc. will work
5581 correctly. This is precisely analogous to what we do in
5582 begin_class_definition when defining an ordinary non-template
5586 /* Now members are processed in the order of declaration. */
5587 for (member = CLASSTYPE_DECL_LIST (pattern);
5588 member; member = TREE_CHAIN (member))
5590 tree t = TREE_VALUE (member);
5592 if (TREE_PURPOSE (member))
5596 /* Build new CLASSTYPE_NESTED_UTDS. */
5599 tree name = TYPE_IDENTIFIER (tag);
5601 bool class_template_p;
5603 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5604 && TYPE_LANG_SPECIFIC (tag)
5605 && CLASSTYPE_IS_TEMPLATE (tag));
5606 /* If the member is a class template, then -- even after
5607 substitution -- there may be dependent types in the
5608 template argument list for the class. We increment
5609 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5610 that function will assume that no types are dependent
5611 when outside of a template. */
5612 if (class_template_p)
5613 ++processing_template_decl;
5614 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5615 if (class_template_p)
5616 --processing_template_decl;
5617 if (newtag == error_mark_node)
5620 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5622 if (class_template_p)
5623 /* Unfortunately, lookup_template_class sets
5624 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5625 instantiation (i.e., for the type of a member
5626 template class nested within a template class.)
5627 This behavior is required for
5628 maybe_process_partial_specialization to work
5629 correctly, but is not accurate in this case;
5630 the TAG is not an instantiation of anything.
5631 (The corresponding TEMPLATE_DECL is an
5632 instantiation, but the TYPE is not.) */
5633 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5635 /* Now, we call pushtag to put this NEWTAG into the scope of
5636 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5637 pushtag calling push_template_decl. We don't have to do
5638 this for enums because it will already have been done in
5641 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5642 pushtag (name, newtag, /*tag_scope=*/ts_current);
5645 else if (TREE_CODE (t) == FUNCTION_DECL
5646 || DECL_FUNCTION_TEMPLATE_P (t))
5648 /* Build new TYPE_METHODS. */
5651 if (TREE_CODE (t) == TEMPLATE_DECL)
5652 ++processing_template_decl;
5653 r = tsubst (t, args, tf_error, NULL_TREE);
5654 if (TREE_CODE (t) == TEMPLATE_DECL)
5655 --processing_template_decl;
5656 set_current_access_from_decl (r);
5657 grok_special_member_properties (r);
5658 finish_member_declaration (r);
5662 /* Build new TYPE_FIELDS. */
5664 if (TREE_CODE (t) != CONST_DECL)
5668 /* The the file and line for this declaration, to
5669 assist in error message reporting. Since we
5670 called push_tinst_level above, we don't need to
5672 input_location = DECL_SOURCE_LOCATION (t);
5674 if (TREE_CODE (t) == TEMPLATE_DECL)
5675 ++processing_template_decl;
5676 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5677 if (TREE_CODE (t) == TEMPLATE_DECL)
5678 --processing_template_decl;
5679 if (TREE_CODE (r) == VAR_DECL)
5683 if (DECL_INITIALIZED_IN_CLASS_P (r))
5684 init = tsubst_expr (DECL_INITIAL (t), args,
5685 tf_error | tf_warning, NULL_TREE);
5689 finish_static_data_member_decl
5690 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5692 if (DECL_INITIALIZED_IN_CLASS_P (r))
5693 check_static_variable_definition (r, TREE_TYPE (r));
5695 else if (TREE_CODE (r) == FIELD_DECL)
5697 /* Determine whether R has a valid type and can be
5698 completed later. If R is invalid, then it is
5699 replaced by error_mark_node so that it will not be
5700 added to TYPE_FIELDS. */
5701 tree rtype = TREE_TYPE (r);
5702 if (can_complete_type_without_circularity (rtype))
5703 complete_type (rtype);
5705 if (!COMPLETE_TYPE_P (rtype))
5707 cxx_incomplete_type_error (r, rtype);
5708 r = error_mark_node;
5712 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5713 such a thing will already have been added to the field
5714 list by tsubst_enum in finish_member_declaration in the
5715 CLASSTYPE_NESTED_UTDS case above. */
5716 if (!(TREE_CODE (r) == TYPE_DECL
5717 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5718 && DECL_ARTIFICIAL (r)))
5720 set_current_access_from_decl (r);
5721 finish_member_declaration (r);
5728 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5730 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5732 tree friend_type = t;
5733 bool adjust_processing_template_decl = false;
5735 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5737 /* template <class T> friend class C; */
5738 friend_type = tsubst_friend_class (friend_type, args);
5739 adjust_processing_template_decl = true;
5741 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5743 /* template <class T> friend class C::D; */
5744 friend_type = tsubst (friend_type, args,
5745 tf_error | tf_warning, NULL_TREE);
5746 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5747 friend_type = TREE_TYPE (friend_type);
5748 adjust_processing_template_decl = true;
5750 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5752 /* This could be either
5756 when dependent_type_p is false or
5758 template <class U> friend class T::C;
5761 friend_type = tsubst (friend_type, args,
5762 tf_error | tf_warning, NULL_TREE);
5763 /* Bump processing_template_decl for correct
5764 dependent_type_p calculation. */
5765 ++processing_template_decl;
5766 if (dependent_type_p (friend_type))
5767 adjust_processing_template_decl = true;
5768 --processing_template_decl;
5770 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
5771 && hidden_name_p (TYPE_NAME (friend_type)))
5775 where C hasn't been declared yet. Let's lookup name
5776 from namespace scope directly, bypassing any name that
5777 come from dependent base class. */
5778 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5780 /* The call to xref_tag_from_type does injection for friend
5782 push_nested_namespace (ns);
5784 xref_tag_from_type (friend_type, NULL_TREE,
5785 /*tag_scope=*/ts_current);
5786 pop_nested_namespace (ns);
5788 else if (uses_template_parms (friend_type))
5789 /* friend class C<T>; */
5790 friend_type = tsubst (friend_type, args,
5791 tf_error | tf_warning, NULL_TREE);
5796 where C is already declared or
5798 friend class C<int>;
5800 We don't have to do anything in these cases. */
5802 if (adjust_processing_template_decl)
5803 /* Trick make_friend_class into realizing that the friend
5804 we're adding is a template, not an ordinary class. It's
5805 important that we use make_friend_class since it will
5806 perform some error-checking and output cross-reference
5808 ++processing_template_decl;
5810 if (friend_type != error_mark_node)
5811 make_friend_class (type, friend_type, /*complain=*/false);
5813 if (adjust_processing_template_decl)
5814 --processing_template_decl;
5818 /* Build new DECL_FRIENDLIST. */
5821 /* The the file and line for this declaration, to
5822 assist in error message reporting. Since we
5823 called push_tinst_level above, we don't need to
5825 input_location = DECL_SOURCE_LOCATION (t);
5827 if (TREE_CODE (t) == TEMPLATE_DECL)
5829 ++processing_template_decl;
5830 push_deferring_access_checks (dk_no_check);
5833 r = tsubst_friend_function (t, args);
5834 add_friend (type, r, /*complain=*/false);
5835 if (TREE_CODE (t) == TEMPLATE_DECL)
5837 pop_deferring_access_checks ();
5838 --processing_template_decl;
5844 /* Set the file and line number information to whatever is given for
5845 the class itself. This puts error messages involving generated
5846 implicit functions at a predictable point, and the same point
5847 that would be used for non-template classes. */
5848 input_location = DECL_SOURCE_LOCATION (typedecl);
5850 unreverse_member_declarations (type);
5851 finish_struct_1 (type);
5852 TYPE_BEING_DEFINED (type) = 0;
5854 /* Now that the class is complete, instantiate default arguments for
5855 any member functions. We don't do this earlier because the
5856 default arguments may reference members of the class. */
5857 if (!PRIMARY_TEMPLATE_P (template))
5858 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5859 if (TREE_CODE (t) == FUNCTION_DECL
5860 /* Implicitly generated member functions will not have template
5861 information; they are not instantiations, but instead are
5862 created "fresh" for each instantiation. */
5863 && DECL_TEMPLATE_INFO (t))
5864 tsubst_default_arguments (t);
5867 pop_from_top_level ();
5868 pop_deferring_access_checks ();
5871 /* The vtable for a template class can be emitted in any translation
5872 unit in which the class is instantiated. When there is no key
5873 method, however, finish_struct_1 will already have added TYPE to
5874 the keyed_classes list. */
5875 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5876 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5882 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5888 else if (TYPE_P (t))
5889 r = tsubst (t, args, complain, in_decl);
5892 r = tsubst_expr (t, args, complain, in_decl);
5894 if (!uses_template_parms (r))
5896 /* Sometimes, one of the args was an expression involving a
5897 template constant parameter, like N - 1. Now that we've
5898 tsubst'd, we might have something like 2 - 1. This will
5899 confuse lookup_template_class, so we do constant folding
5900 here. We have to unset processing_template_decl, to fool
5901 tsubst_copy_and_build() into building an actual tree. */
5903 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5904 as simple as it's going to get, and trying to reprocess
5905 the trees will break. Once tsubst_expr et al DTRT for
5906 non-dependent exprs, this code can go away, as the type
5907 will always be set. */
5910 int saved_processing_template_decl = processing_template_decl;
5911 processing_template_decl = 0;
5912 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5913 tf_error, /*in_decl=*/NULL_TREE,
5914 /*function_p=*/false);
5915 processing_template_decl = saved_processing_template_decl;
5923 /* Substitute ARGS into the vector or list of template arguments T. */
5926 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5928 int len = TREE_VEC_LENGTH (t);
5929 int need_new = 0, i;
5930 tree *elts = alloca (len * sizeof (tree));
5932 for (i = 0; i < len; i++)
5934 tree orig_arg = TREE_VEC_ELT (t, i);
5937 if (TREE_CODE (orig_arg) == TREE_VEC)
5938 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5940 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5942 if (new_arg == error_mark_node)
5943 return error_mark_node;
5946 if (new_arg != orig_arg)
5953 t = make_tree_vec (len);
5954 for (i = 0; i < len; i++)
5955 TREE_VEC_ELT (t, i) = elts[i];
5960 /* Return the result of substituting ARGS into the template parameters
5961 given by PARMS. If there are m levels of ARGS and m + n levels of
5962 PARMS, then the result will contain n levels of PARMS. For
5963 example, if PARMS is `template <class T> template <class U>
5964 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5965 result will be `template <int*, double, class V>'. */
5968 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5973 for (new_parms = &r;
5974 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5975 new_parms = &(TREE_CHAIN (*new_parms)),
5976 parms = TREE_CHAIN (parms))
5979 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5982 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5984 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5985 tree default_value = TREE_PURPOSE (tuple);
5986 tree parm_decl = TREE_VALUE (tuple);
5988 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5989 default_value = tsubst_template_arg (default_value, args,
5990 complain, NULL_TREE);
5992 tuple = build_tree_list (default_value, parm_decl);
5993 TREE_VEC_ELT (new_vec, i) = tuple;
5997 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
5998 - TMPL_ARGS_DEPTH (args)),
5999 new_vec, NULL_TREE);
6005 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6006 type T. If T is not an aggregate or enumeration type, it is
6007 handled as if by tsubst. IN_DECL is as for tsubst. If
6008 ENTERING_SCOPE is nonzero, T is the context for a template which
6009 we are presently tsubst'ing. Return the substituted value. */
6012 tsubst_aggr_type (tree t,
6014 tsubst_flags_t complain,
6021 switch (TREE_CODE (t))
6024 if (TYPE_PTRMEMFUNC_P (t))
6025 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6027 /* Else fall through. */
6030 if (TYPE_TEMPLATE_INFO (t))
6036 /* First, determine the context for the type we are looking
6038 context = TYPE_CONTEXT (t);
6040 context = tsubst_aggr_type (context, args, complain,
6041 in_decl, /*entering_scope=*/1);
6043 /* Then, figure out what arguments are appropriate for the
6044 type we are trying to find. For example, given:
6046 template <class T> struct S;
6047 template <class T, class U> void f(T, U) { S<U> su; }
6049 and supposing that we are instantiating f<int, double>,
6050 then our ARGS will be {int, double}, but, when looking up
6051 S we only want {double}. */
6052 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6054 if (argvec == error_mark_node)
6055 return error_mark_node;
6057 r = lookup_template_class (t, argvec, in_decl, context,
6058 entering_scope, complain);
6060 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6063 /* This is not a template type, so there's nothing to do. */
6067 return tsubst (t, args, complain, in_decl);
6071 /* Substitute into the default argument ARG (a default argument for
6072 FN), which has the indicated TYPE. */
6075 tsubst_default_argument (tree fn, tree type, tree arg)
6077 tree saved_class_ptr = NULL_TREE;
6078 tree saved_class_ref = NULL_TREE;
6080 /* This default argument came from a template. Instantiate the
6081 default argument here, not in tsubst. In the case of
6090 we must be careful to do name lookup in the scope of S<T>,
6091 rather than in the current class. */
6092 push_access_scope (fn);
6093 /* The default argument expression should not be considered to be
6094 within the scope of FN. Since push_access_scope sets
6095 current_function_decl, we must explicitly clear it here. */
6096 current_function_decl = NULL_TREE;
6097 /* The "this" pointer is not valid in a default argument. */
6100 saved_class_ptr = current_class_ptr;
6101 cp_function_chain->x_current_class_ptr = NULL_TREE;
6102 saved_class_ref = current_class_ref;
6103 cp_function_chain->x_current_class_ref = NULL_TREE;
6106 push_deferring_access_checks(dk_no_deferred);
6107 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6108 tf_error | tf_warning, NULL_TREE);
6109 pop_deferring_access_checks();
6111 /* Restore the "this" pointer. */
6114 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6115 cp_function_chain->x_current_class_ref = saved_class_ref;
6118 pop_access_scope (fn);
6120 /* Make sure the default argument is reasonable. */
6121 arg = check_default_argument (type, arg);
6126 /* Substitute into all the default arguments for FN. */
6129 tsubst_default_arguments (tree fn)
6134 tmpl_args = DECL_TI_ARGS (fn);
6136 /* If this function is not yet instantiated, we certainly don't need
6137 its default arguments. */
6138 if (uses_template_parms (tmpl_args))
6141 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6143 arg = TREE_CHAIN (arg))
6144 if (TREE_PURPOSE (arg))
6145 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6147 TREE_PURPOSE (arg));
6150 /* Substitute the ARGS into the T, which is a _DECL. Return the
6151 result of the substitution. Issue error and warning messages under
6152 control of COMPLAIN. */
6155 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6157 location_t saved_loc;
6161 /* Set the filename and linenumber to improve error-reporting. */
6162 saved_loc = input_location;
6163 input_location = DECL_SOURCE_LOCATION (t);
6165 switch (TREE_CODE (t))
6169 /* We can get here when processing a member function template,
6170 member class template, and template template parameter of
6171 a template class. */
6172 tree decl = DECL_TEMPLATE_RESULT (t);
6177 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6179 /* Template template parameter is treated here. */
6180 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6181 if (new_type == error_mark_node)
6182 return error_mark_node;
6185 TREE_CHAIN (r) = NULL_TREE;
6186 TREE_TYPE (r) = new_type;
6187 DECL_TEMPLATE_RESULT (r)
6188 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6189 DECL_TEMPLATE_PARMS (r)
6190 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6192 TYPE_NAME (new_type) = r;
6196 /* We might already have an instance of this template.
6197 The ARGS are for the surrounding class type, so the
6198 full args contain the tsubst'd args for the context,
6199 plus the innermost args from the template decl. */
6200 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6201 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6202 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6203 full_args = tsubst_template_args (tmpl_args, args,
6206 /* tsubst_template_args doesn't copy the vector if
6207 nothing changed. But, *something* should have
6209 gcc_assert (full_args != tmpl_args);
6211 spec = retrieve_specialization (t, full_args,
6212 /*class_specializations_p=*/true);
6213 if (spec != NULL_TREE)
6219 /* Make a new template decl. It will be similar to the
6220 original, but will record the current template arguments.
6221 We also create a new function declaration, which is just
6222 like the old one, but points to this new template, rather
6223 than the old one. */
6225 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6226 TREE_CHAIN (r) = NULL_TREE;
6229 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6231 /*entering_scope=*/1);
6232 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6234 if (TREE_CODE (decl) == TYPE_DECL)
6236 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6237 if (new_type == error_mark_node)
6238 return error_mark_node;
6240 TREE_TYPE (r) = new_type;
6241 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6242 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6243 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6247 tree new_decl = tsubst (decl, args, complain, in_decl);
6248 if (new_decl == error_mark_node)
6249 return error_mark_node;
6251 DECL_TEMPLATE_RESULT (r) = new_decl;
6252 DECL_TI_TEMPLATE (new_decl) = r;
6253 TREE_TYPE (r) = TREE_TYPE (new_decl);
6254 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6257 SET_DECL_IMPLICIT_INSTANTIATION (r);
6258 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6259 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6261 /* The template parameters for this new template are all the
6262 template parameters for the old template, except the
6263 outermost level of parameters. */
6264 DECL_TEMPLATE_PARMS (r)
6265 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6268 if (PRIMARY_TEMPLATE_P (t))
6269 DECL_PRIMARY_TEMPLATE (r) = r;
6271 if (TREE_CODE (decl) != TYPE_DECL)
6272 /* Record this non-type partial instantiation. */
6273 register_specialization (r, t,
6274 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6281 tree argvec = NULL_TREE;
6289 /* Nobody should be tsubst'ing into non-template functions. */
6290 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6292 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6297 /* If T is not dependent, just return it. We have to
6298 increment PROCESSING_TEMPLATE_DECL because
6299 value_dependent_expression_p assumes that nothing is
6300 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6301 ++processing_template_decl;
6302 dependent_p = value_dependent_expression_p (t);
6303 --processing_template_decl;
6307 /* Calculate the most general template of which R is a
6308 specialization, and the complete set of arguments used to
6310 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6311 argvec = tsubst_template_args (DECL_TI_ARGS
6312 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6313 args, complain, in_decl);
6315 /* Check to see if we already have this specialization. */
6316 spec = retrieve_specialization (gen_tmpl, argvec,
6317 /*class_specializations_p=*/false);
6325 /* We can see more levels of arguments than parameters if
6326 there was a specialization of a member template, like
6329 template <class T> struct S { template <class U> void f(); }
6330 template <> template <class U> void S<int>::f(U);
6332 Here, we'll be substituting into the specialization,
6333 because that's where we can find the code we actually
6334 want to generate, but we'll have enough arguments for
6335 the most general template.
6337 We also deal with the peculiar case:
6339 template <class T> struct S {
6340 template <class U> friend void f();
6342 template <class U> void f() {}
6344 template void f<double>();
6346 Here, the ARGS for the instantiation of will be {int,
6347 double}. But, we only need as many ARGS as there are
6348 levels of template parameters in CODE_PATTERN. We are
6349 careful not to get fooled into reducing the ARGS in
6352 template <class T> struct S { template <class U> void f(U); }
6353 template <class T> template <> void S<T>::f(int) {}
6355 which we can spot because the pattern will be a
6356 specialization in this case. */
6357 args_depth = TMPL_ARGS_DEPTH (args);
6359 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6360 if (args_depth > parms_depth
6361 && !DECL_TEMPLATE_SPECIALIZATION (t))
6362 args = get_innermost_template_args (args, parms_depth);
6366 /* This special case arises when we have something like this:
6368 template <class T> struct S {
6369 friend void f<int>(int, double);
6372 Here, the DECL_TI_TEMPLATE for the friend declaration
6373 will be an IDENTIFIER_NODE. We are being called from
6374 tsubst_friend_function, and we want only to create a
6375 new decl (R) with appropriate types so that we can call
6376 determine_specialization. */
6377 gen_tmpl = NULL_TREE;
6380 if (DECL_CLASS_SCOPE_P (t))
6382 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6386 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6387 complain, t, /*entering_scope=*/1);
6392 ctx = DECL_CONTEXT (t);
6394 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6395 if (type == error_mark_node)
6396 return error_mark_node;
6398 /* We do NOT check for matching decls pushed separately at this
6399 point, as they may not represent instantiations of this
6400 template, and in any case are considered separate under the
6403 DECL_USE_TEMPLATE (r) = 0;
6404 TREE_TYPE (r) = type;
6405 /* Clear out the mangled name and RTL for the instantiation. */
6406 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6407 SET_DECL_RTL (r, NULL_RTX);
6408 DECL_INITIAL (r) = NULL_TREE;
6409 DECL_CONTEXT (r) = ctx;
6411 if (member && DECL_CONV_FN_P (r))
6412 /* Type-conversion operator. Reconstruct the name, in
6413 case it's the name of one of the template's parameters. */
6414 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6416 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6418 DECL_RESULT (r) = NULL_TREE;
6420 TREE_STATIC (r) = 0;
6421 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6422 DECL_EXTERNAL (r) = 1;
6423 /* If this is an instantiation of a function with internal
6424 linkage, we already know what object file linkage will be
6425 assigned to the instantiation. */
6426 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6427 DECL_DEFER_OUTPUT (r) = 0;
6428 TREE_CHAIN (r) = NULL_TREE;
6429 DECL_PENDING_INLINE_INFO (r) = 0;
6430 DECL_PENDING_INLINE_P (r) = 0;
6431 DECL_SAVED_TREE (r) = NULL_TREE;
6433 if (DECL_CLONED_FUNCTION (r))
6435 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6437 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6438 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6441 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6442 this in the special friend case mentioned above where
6443 GEN_TMPL is NULL. */
6446 DECL_TEMPLATE_INFO (r)
6447 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6448 SET_DECL_IMPLICIT_INSTANTIATION (r);
6449 register_specialization (r, gen_tmpl, argvec);
6451 /* We're not supposed to instantiate default arguments
6452 until they are called, for a template. But, for a
6455 template <class T> void f ()
6456 { extern void g(int i = T()); }
6458 we should do the substitution when the template is
6459 instantiated. We handle the member function case in
6460 instantiate_class_template since the default arguments
6461 might refer to other members of the class. */
6463 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6464 && !uses_template_parms (argvec))
6465 tsubst_default_arguments (r);
6468 /* Copy the list of befriending classes. */
6469 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6471 friends = &TREE_CHAIN (*friends))
6473 *friends = copy_node (*friends);
6474 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6479 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6481 maybe_retrofit_in_chrg (r);
6482 if (DECL_CONSTRUCTOR_P (r))
6483 grok_ctor_properties (ctx, r);
6484 /* If this is an instantiation of a member template, clone it.
6485 If it isn't, that'll be handled by
6486 clone_constructors_and_destructors. */
6487 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6488 clone_function_decl (r, /*update_method_vec_p=*/0);
6490 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6491 grok_op_properties (r, (complain & tf_error) != 0);
6493 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6494 SET_DECL_FRIEND_CONTEXT (r,
6495 tsubst (DECL_FRIEND_CONTEXT (t),
6496 args, complain, in_decl));
6505 if (DECL_TEMPLATE_PARM_P (t))
6506 SET_DECL_TEMPLATE_PARM_P (r);
6508 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6509 type = type_decays_to (type);
6510 TREE_TYPE (r) = type;
6511 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6513 if (DECL_INITIAL (r))
6515 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6516 DECL_INITIAL (r) = TREE_TYPE (r);
6518 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6522 DECL_CONTEXT (r) = NULL_TREE;
6524 if (!DECL_TEMPLATE_PARM_P (r))
6525 DECL_ARG_TYPE (r) = type_passed_as (type);
6527 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6528 complain, TREE_CHAIN (t));
6537 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6538 if (type == error_mark_node)
6539 return error_mark_node;
6540 TREE_TYPE (r) = type;
6541 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6543 /* We don't have to set DECL_CONTEXT here; it is set by
6544 finish_member_declaration. */
6545 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6547 TREE_CHAIN (r) = NULL_TREE;
6548 if (VOID_TYPE_P (type))
6549 error ("instantiation of %q+D as type %qT", r, type);
6554 /* We reach here only for member using decls. */
6555 if (DECL_DEPENDENT_P (t))
6557 r = do_class_using_decl
6558 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
6559 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
6561 r = error_mark_node;
6566 TREE_CHAIN (r) = NULL_TREE;
6573 tree argvec = NULL_TREE;
6574 tree gen_tmpl = NULL_TREE;
6576 tree tmpl = NULL_TREE;
6578 tree type = NULL_TREE;
6581 if (TREE_CODE (t) == TYPE_DECL)
6583 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6584 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6585 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6587 /* If this is the canonical decl, we don't have to
6588 mess with instantiations, and often we can't (for
6589 typename, template type parms and such). Note that
6590 TYPE_NAME is not correct for the above test if
6591 we've copied the type for a typedef. */
6592 r = TYPE_NAME (type);
6597 /* Assume this is a non-local variable. */
6600 if (TYPE_P (CP_DECL_CONTEXT (t)))
6601 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6603 in_decl, /*entering_scope=*/1);
6604 else if (DECL_NAMESPACE_SCOPE_P (t))
6605 ctx = DECL_CONTEXT (t);
6608 /* Subsequent calls to pushdecl will fill this in. */
6613 /* Check to see if we already have this specialization. */
6616 tmpl = DECL_TI_TEMPLATE (t);
6617 gen_tmpl = most_general_template (tmpl);
6618 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6619 spec = retrieve_specialization (gen_tmpl, argvec,
6620 /*class_specializations_p=*/false);
6623 spec = retrieve_local_specialization (t);
6632 if (TREE_CODE (r) == VAR_DECL)
6634 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6635 if (type == error_mark_node)
6636 return error_mark_node;
6637 type = complete_type (type);
6638 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6639 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6640 type = check_var_type (DECL_NAME (r), type);
6642 else if (DECL_SELF_REFERENCE_P (t))
6643 SET_DECL_SELF_REFERENCE_P (r);
6644 TREE_TYPE (r) = type;
6645 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6646 DECL_CONTEXT (r) = ctx;
6647 /* Clear out the mangled name and RTL for the instantiation. */
6648 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6649 SET_DECL_RTL (r, NULL_RTX);
6651 /* Don't try to expand the initializer until someone tries to use
6652 this variable; otherwise we run into circular dependencies. */
6653 DECL_INITIAL (r) = NULL_TREE;
6654 SET_DECL_RTL (r, NULL_RTX);
6655 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6657 /* Even if the original location is out of scope, the newly
6658 substituted one is not. */
6659 if (TREE_CODE (r) == VAR_DECL)
6661 DECL_DEAD_FOR_LOCAL (r) = 0;
6662 DECL_INITIALIZED_P (r) = 0;
6667 /* A static data member declaration is always marked
6668 external when it is declared in-class, even if an
6669 initializer is present. We mimic the non-template
6671 DECL_EXTERNAL (r) = 1;
6673 register_specialization (r, gen_tmpl, argvec);
6674 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6675 SET_DECL_IMPLICIT_INSTANTIATION (r);
6678 register_local_specialization (r, t);
6680 TREE_CHAIN (r) = NULL_TREE;
6689 /* Restore the file and line information. */
6690 input_location = saved_loc;
6695 /* Substitute into the ARG_TYPES of a function type. */
6698 tsubst_arg_types (tree arg_types,
6700 tsubst_flags_t complain,
6703 tree remaining_arg_types;
6706 tree result = NULL_TREE;
6708 if (!arg_types || arg_types == void_list_node)
6711 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6712 args, complain, in_decl);
6713 if (remaining_arg_types == error_mark_node)
6714 return error_mark_node;
6716 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6717 if (type == error_mark_node)
6718 return error_mark_node;
6719 if (VOID_TYPE_P (type))
6721 if (complain & tf_error)
6723 error ("invalid parameter type %qT", type);
6725 error ("in declaration %q+D", in_decl);
6727 return error_mark_node;
6730 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6731 top-level qualifiers as required. */
6732 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6734 /* We do not substitute into default arguments here. The standard
6735 mandates that they be instantiated only when needed, which is
6736 done in build_over_call. */
6737 default_arg = TREE_PURPOSE (arg_types);
6739 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
6741 /* We've instantiated a template before its default arguments
6742 have been parsed. This can happen for a nested template
6743 class, and is not an error unless we require the default
6744 argument in a call of this function. */
6745 result = tree_cons (default_arg, type, remaining_arg_types);
6746 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
6749 result = hash_tree_cons (default_arg, type, remaining_arg_types);
6754 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6755 *not* handle the exception-specification for FNTYPE, because the
6756 initial substitution of explicitly provided template parameters
6757 during argument deduction forbids substitution into the
6758 exception-specification:
6762 All references in the function type of the function template to the
6763 corresponding template parameters are replaced by the specified tem-
6764 plate argument values. If a substitution in a template parameter or
6765 in the function type of the function template results in an invalid
6766 type, type deduction fails. [Note: The equivalent substitution in
6767 exception specifications is done only when the function is instanti-
6768 ated, at which point a program is ill-formed if the substitution
6769 results in an invalid type.] */
6772 tsubst_function_type (tree t,
6774 tsubst_flags_t complain,
6781 /* The TYPE_CONTEXT is not used for function/method types. */
6782 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6784 /* Substitute the return type. */
6785 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6786 if (return_type == error_mark_node)
6787 return error_mark_node;
6788 /* The standard does not presently indicate that creation of a
6789 function type with an invalid return type is a deduction failure.
6790 However, that is clearly analogous to creating an array of "void"
6791 or a reference to a reference. This is core issue #486. */
6792 if (TREE_CODE (return_type) == ARRAY_TYPE
6793 || TREE_CODE (return_type) == FUNCTION_TYPE)
6795 if (complain & tf_error)
6797 if (TREE_CODE (return_type) == ARRAY_TYPE)
6798 error ("function returning an array");
6800 error ("function returning a function");
6802 return error_mark_node;
6805 /* Substitute the argument types. */
6806 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6808 if (arg_types == error_mark_node)
6809 return error_mark_node;
6811 /* Construct a new type node and return it. */
6812 if (TREE_CODE (t) == FUNCTION_TYPE)
6813 fntype = build_function_type (return_type, arg_types);
6816 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6817 if (! IS_AGGR_TYPE (r))
6821 Type deduction may fail for any of the following
6824 -- Attempting to create "pointer to member of T" when T
6825 is not a class type. */
6826 if (complain & tf_error)
6827 error ("creating pointer to member function of non-class type %qT",
6829 return error_mark_node;
6832 fntype = build_method_type_directly (r, return_type,
6833 TREE_CHAIN (arg_types));
6835 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6836 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6841 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6842 ARGS into that specification, and return the substituted
6843 specification. If there is no specification, return NULL_TREE. */
6846 tsubst_exception_specification (tree fntype,
6848 tsubst_flags_t complain,
6854 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6855 new_specs = NULL_TREE;
6858 if (! TREE_VALUE (specs))
6864 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6865 if (spec == error_mark_node)
6867 new_specs = add_exception_specifier (new_specs, spec, complain);
6868 specs = TREE_CHAIN (specs);
6874 /* Substitute into the PARMS of a call-declarator. */
6877 tsubst_call_declarator_parms (tree parms,
6879 tsubst_flags_t complain,
6886 if (!parms || parms == void_list_node)
6889 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6890 args, complain, in_decl);
6892 /* Figure out the type of this parameter. */
6893 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6895 /* Figure out the default argument as well. Note that we use
6896 tsubst_expr since the default argument is really an expression. */
6897 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6899 /* Chain this parameter on to the front of those we have already
6900 processed. We don't use hash_tree_cons because that function
6901 doesn't check TREE_PARMLIST. */
6902 new_parms = tree_cons (defarg, type, new_parms);
6907 /* Take the tree structure T and replace template parameters used
6908 therein with the argument vector ARGS. IN_DECL is an associated
6909 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6910 Issue error and warning messages under control of COMPLAIN. Note
6911 that we must be relatively non-tolerant of extensions here, in
6912 order to preserve conformance; if we allow substitutions that
6913 should not be allowed, we may allow argument deductions that should
6914 not succeed, and therefore report ambiguous overload situations
6915 where there are none. In theory, we could allow the substitution,
6916 but indicate that it should have failed, and allow our caller to
6917 make sure that the right thing happens, but we don't try to do this
6920 This function is used for dealing with types, decls and the like;
6921 for expressions, use tsubst_expr or tsubst_copy. */
6924 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6928 if (t == NULL_TREE || t == error_mark_node
6929 || t == integer_type_node
6930 || t == void_type_node
6931 || t == char_type_node
6932 || t == unknown_type_node
6933 || TREE_CODE (t) == NAMESPACE_DECL)
6937 return tsubst_decl (t, args, complain);
6939 if (TREE_CODE (t) == IDENTIFIER_NODE)
6940 type = IDENTIFIER_TYPE_VALUE (t);
6942 type = TREE_TYPE (t);
6944 gcc_assert (type != unknown_type_node);
6947 && TREE_CODE (t) != TYPENAME_TYPE
6948 && TREE_CODE (t) != IDENTIFIER_NODE
6949 && TREE_CODE (t) != FUNCTION_TYPE
6950 && TREE_CODE (t) != METHOD_TYPE)
6951 type = tsubst (type, args, complain, in_decl);
6952 if (type == error_mark_node)
6953 return error_mark_node;
6955 switch (TREE_CODE (t))
6960 return tsubst_aggr_type (t, args, complain, in_decl,
6961 /*entering_scope=*/0);
6964 case IDENTIFIER_NODE:
6976 if (t == integer_type_node)
6979 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6980 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6984 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6986 /* The array dimension behaves like a non-type template arg,
6987 in that we want to fold it as much as possible. */
6988 max = tsubst_template_arg (omax, args, complain, in_decl);
6989 max = fold_decl_constant_value (max);
6991 if (integer_zerop (omax))
6993 /* Still allow an explicit array of size zero. */
6995 pedwarn ("creating array with size zero");
6997 else if (integer_zerop (max)
6998 || (TREE_CODE (max) == INTEGER_CST
6999 && INT_CST_LT (max, integer_zero_node)))
7003 Type deduction may fail for any of the following
7006 Attempting to create an array with a size that is
7007 zero or negative. */
7008 if (complain & tf_error)
7009 error ("creating array with size zero (%qE)", max);
7011 return error_mark_node;
7014 return compute_array_index_type (NULL_TREE, max);
7017 case TEMPLATE_TYPE_PARM:
7018 case TEMPLATE_TEMPLATE_PARM:
7019 case BOUND_TEMPLATE_TEMPLATE_PARM:
7020 case TEMPLATE_PARM_INDEX:
7025 tree arg = NULL_TREE;
7029 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7030 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7031 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7032 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7034 idx = TEMPLATE_TYPE_IDX (t);
7035 level = TEMPLATE_TYPE_LEVEL (t);
7039 idx = TEMPLATE_PARM_IDX (t);
7040 level = TEMPLATE_PARM_LEVEL (t);
7043 levels = TMPL_ARGS_DEPTH (args);
7044 if (level <= levels)
7045 arg = TMPL_ARG (args, level, idx);
7047 if (arg == error_mark_node)
7048 return error_mark_node;
7049 else if (arg != NULL_TREE)
7051 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7053 gcc_assert (TYPE_P (arg));
7054 return cp_build_qualified_type_real
7055 (arg, cp_type_quals (arg) | cp_type_quals (t),
7056 complain | tf_ignore_bad_quals);
7058 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7060 /* We are processing a type constructed from a
7061 template template parameter. */
7062 tree argvec = tsubst (TYPE_TI_ARGS (t),
7063 args, complain, in_decl);
7064 if (argvec == error_mark_node)
7065 return error_mark_node;
7067 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7068 are resolving nested-types in the signature of a
7069 member function templates. Otherwise ARG is a
7070 TEMPLATE_DECL and is the real template to be
7072 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7073 arg = TYPE_NAME (arg);
7075 r = lookup_template_class (arg,
7078 /*entering_scope=*/0,
7080 return cp_build_qualified_type_real
7081 (r, TYPE_QUALS (t), complain);
7084 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7089 /* This can happen during the attempted tsubst'ing in
7090 unify. This means that we don't yet have any information
7091 about the template parameter in question. */
7094 /* If we get here, we must have been looking at a parm for a
7095 more deeply nested template. Make a new version of this
7096 template parameter, but with a lower level. */
7097 switch (TREE_CODE (t))
7099 case TEMPLATE_TYPE_PARM:
7100 case TEMPLATE_TEMPLATE_PARM:
7101 case BOUND_TEMPLATE_TEMPLATE_PARM:
7102 if (cp_type_quals (t))
7104 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7105 r = cp_build_qualified_type_real
7106 (r, cp_type_quals (t),
7107 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7108 ? tf_ignore_bad_quals : 0));
7113 TEMPLATE_TYPE_PARM_INDEX (r)
7114 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7116 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7117 TYPE_MAIN_VARIANT (r) = r;
7118 TYPE_POINTER_TO (r) = NULL_TREE;
7119 TYPE_REFERENCE_TO (r) = NULL_TREE;
7121 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7123 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7125 if (argvec == error_mark_node)
7126 return error_mark_node;
7128 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7129 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7134 case TEMPLATE_PARM_INDEX:
7135 r = reduce_template_parm_level (t, type, levels);
7147 tree purpose, value, chain;
7149 if (t == void_list_node)
7152 purpose = TREE_PURPOSE (t);
7155 purpose = tsubst (purpose, args, complain, in_decl);
7156 if (purpose == error_mark_node)
7157 return error_mark_node;
7159 value = TREE_VALUE (t);
7162 value = tsubst (value, args, complain, in_decl);
7163 if (value == error_mark_node)
7164 return error_mark_node;
7166 chain = TREE_CHAIN (t);
7167 if (chain && chain != void_type_node)
7169 chain = tsubst (chain, args, complain, in_decl);
7170 if (chain == error_mark_node)
7171 return error_mark_node;
7173 if (purpose == TREE_PURPOSE (t)
7174 && value == TREE_VALUE (t)
7175 && chain == TREE_CHAIN (t))
7177 return hash_tree_cons (purpose, value, chain);
7181 /* We should never be tsubsting a binfo. */
7185 /* A vector of template arguments. */
7187 return tsubst_template_args (t, args, complain, in_decl);
7190 case REFERENCE_TYPE:
7192 enum tree_code code;
7194 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7197 code = TREE_CODE (t);
7202 Type deduction may fail for any of the following
7205 -- Attempting to create a pointer to reference type.
7206 -- Attempting to create a reference to a reference type or
7207 a reference to void. */
7208 if (TREE_CODE (type) == REFERENCE_TYPE
7209 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7211 static location_t last_loc;
7213 /* We keep track of the last time we issued this error
7214 message to avoid spewing a ton of messages during a
7215 single bad template instantiation. */
7216 if (complain & tf_error
7217 #ifdef USE_MAPPED_LOCATION
7218 && last_loc != input_location
7220 && (last_loc.line != input_line
7221 || last_loc.file != input_filename)
7225 if (TREE_CODE (type) == VOID_TYPE)
7226 error ("forming reference to void");
7228 error ("forming %s to reference type %qT",
7229 (code == POINTER_TYPE) ? "pointer" : "reference",
7231 last_loc = input_location;
7234 return error_mark_node;
7236 else if (code == POINTER_TYPE)
7238 r = build_pointer_type (type);
7239 if (TREE_CODE (type) == METHOD_TYPE)
7240 r = build_ptrmemfunc_type (r);
7243 r = build_reference_type (type);
7244 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7246 if (r != error_mark_node)
7247 /* Will this ever be needed for TYPE_..._TO values? */
7254 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7255 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7259 Type deduction may fail for any of the following
7262 -- Attempting to create "pointer to member of T" when T
7263 is not a class type. */
7264 if (complain & tf_error)
7265 error ("creating pointer to member of non-class type %qT", r);
7266 return error_mark_node;
7268 if (TREE_CODE (type) == REFERENCE_TYPE)
7270 if (complain & tf_error)
7271 error ("creating pointer to member reference type %qT", type);
7272 return error_mark_node;
7274 if (TREE_CODE (type) == VOID_TYPE)
7276 if (complain & tf_error)
7277 error ("creating pointer to member of type void");
7278 return error_mark_node;
7280 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7281 if (TREE_CODE (type) == FUNCTION_TYPE)
7283 /* The type of the implicit object parameter gets its
7284 cv-qualifiers from the FUNCTION_TYPE. */
7286 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7287 cp_type_quals (type));
7289 method_type = build_method_type_directly (this_type,
7291 TYPE_ARG_TYPES (type));
7292 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7293 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7297 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7306 fntype = tsubst_function_type (t, args, complain, in_decl);
7307 if (fntype == error_mark_node)
7308 return error_mark_node;
7310 /* Substitute the exception specification. */
7311 specs = tsubst_exception_specification (t, args, complain,
7314 fntype = build_exception_variant (fntype, specs);
7319 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7320 if (domain == error_mark_node)
7321 return error_mark_node;
7323 /* As an optimization, we avoid regenerating the array type if
7324 it will obviously be the same as T. */
7325 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7328 /* These checks should match the ones in grokdeclarator.
7332 The deduction may fail for any of the following reasons:
7334 -- Attempting to create an array with an element type that
7335 is void, a function type, or a reference type, or [DR337]
7336 an abstract class type. */
7337 if (TREE_CODE (type) == VOID_TYPE
7338 || TREE_CODE (type) == FUNCTION_TYPE
7339 || TREE_CODE (type) == REFERENCE_TYPE)
7341 if (complain & tf_error)
7342 error ("creating array of %qT", type);
7343 return error_mark_node;
7345 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7347 if (complain & tf_error)
7348 error ("creating array of %qT, which is an abstract class type",
7350 return error_mark_node;
7353 r = build_cplus_array_type (type, domain);
7360 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7361 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7363 if (e1 == error_mark_node || e2 == error_mark_node)
7364 return error_mark_node;
7366 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7372 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7373 if (e == error_mark_node)
7374 return error_mark_node;
7376 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7381 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7382 in_decl, /*entering_scope=*/1);
7383 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7386 if (ctx == error_mark_node || f == error_mark_node)
7387 return error_mark_node;
7389 if (!IS_AGGR_TYPE (ctx))
7391 if (complain & tf_error)
7392 error ("%qT is not a class, struct, or union type", ctx);
7393 return error_mark_node;
7395 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7397 /* Normally, make_typename_type does not require that the CTX
7398 have complete type in order to allow things like:
7400 template <class T> struct S { typename S<T>::X Y; };
7402 But, such constructs have already been resolved by this
7403 point, so here CTX really should have complete type, unless
7404 it's a partial instantiation. */
7405 ctx = complete_type (ctx);
7406 if (!COMPLETE_TYPE_P (ctx))
7408 if (complain & tf_error)
7409 cxx_incomplete_type_error (NULL_TREE, ctx);
7410 return error_mark_node;
7414 f = make_typename_type (ctx, f, typename_type,
7415 (complain & tf_error) | tf_keep_type_decl);
7416 if (f == error_mark_node)
7418 if (TREE_CODE (f) == TYPE_DECL)
7420 complain |= tf_ignore_bad_quals;
7424 if (TREE_CODE (f) != TYPENAME_TYPE)
7426 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7427 error ("%qT resolves to %qT, which is not an enumeration type",
7429 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7430 error ("%qT resolves to %qT, which is is not a class type",
7434 return cp_build_qualified_type_real
7435 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7438 case UNBOUND_CLASS_TEMPLATE:
7440 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7441 in_decl, /*entering_scope=*/1);
7442 tree name = TYPE_IDENTIFIER (t);
7443 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7445 if (ctx == error_mark_node || name == error_mark_node)
7446 return error_mark_node;
7449 parm_list = tsubst_template_parms (parm_list, args, complain);
7450 return make_unbound_class_template (ctx, name, parm_list, complain);
7460 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7461 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7462 if (e1 == error_mark_node || e2 == error_mark_node)
7463 return error_mark_node;
7465 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7470 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7471 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7472 if (e1 == error_mark_node || e2 == error_mark_node)
7473 return error_mark_node;
7475 return build_nt (TREE_CODE (t), e1, e2);
7482 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7483 complain, in_decl));
7484 return cp_build_qualified_type_real (type,
7486 | cp_type_quals (type),
7491 sorry ("use of %qs in template",
7492 tree_code_name [(int) TREE_CODE (t)]);
7493 return error_mark_node;
7497 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7498 type of the expression on the left-hand side of the "." or "->"
7502 tsubst_baselink (tree baselink, tree object_type,
7503 tree args, tsubst_flags_t complain, tree in_decl)
7506 tree qualifying_scope;
7508 tree template_args = 0;
7509 bool template_id_p = false;
7511 /* A baselink indicates a function from a base class. The
7512 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7513 non-dependent types; otherwise, the lookup could not have
7514 succeeded. However, they may indicate bases of the template
7515 class, rather than the instantiated class.
7517 In addition, lookups that were not ambiguous before may be
7518 ambiguous now. Therefore, we perform the lookup again. */
7519 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7520 fns = BASELINK_FUNCTIONS (baselink);
7521 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7523 template_id_p = true;
7524 template_args = TREE_OPERAND (fns, 1);
7525 fns = TREE_OPERAND (fns, 0);
7527 template_args = tsubst_template_args (template_args, args,
7530 name = DECL_NAME (get_first_fn (fns));
7531 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7533 /* If lookup found a single function, mark it as used at this
7534 point. (If it lookup found multiple functions the one selected
7535 later by overload resolution will be marked as used at that
7537 if (BASELINK_P (baselink))
7538 fns = BASELINK_FUNCTIONS (baselink);
7539 if (!template_id_p && !really_overloaded_fn (fns))
7540 mark_used (OVL_CURRENT (fns));
7542 /* Add back the template arguments, if present. */
7543 if (BASELINK_P (baselink) && template_id_p)
7544 BASELINK_FUNCTIONS (baselink)
7545 = build_nt (TEMPLATE_ID_EXPR,
7546 BASELINK_FUNCTIONS (baselink),
7550 object_type = current_class_type;
7551 return adjust_result_of_qualified_name_lookup (baselink,
7556 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7557 true if the qualified-id will be a postfix-expression in-and-of
7558 itself; false if more of the postfix-expression follows the
7559 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7563 tsubst_qualified_id (tree qualified_id, tree args,
7564 tsubst_flags_t complain, tree in_decl,
7565 bool done, bool address_p)
7573 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7575 /* Figure out what name to look up. */
7576 name = TREE_OPERAND (qualified_id, 1);
7577 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7580 template_args = TREE_OPERAND (name, 1);
7582 template_args = tsubst_template_args (template_args, args,
7584 name = TREE_OPERAND (name, 0);
7588 is_template = false;
7589 template_args = NULL_TREE;
7592 /* Substitute into the qualifying scope. When there are no ARGS, we
7593 are just trying to simplify a non-dependent expression. In that
7594 case the qualifying scope may be dependent, and, in any case,
7595 substituting will not help. */
7596 scope = TREE_OPERAND (qualified_id, 0);
7599 scope = tsubst (scope, args, complain, in_decl);
7600 expr = tsubst_copy (name, args, complain, in_decl);
7605 if (dependent_type_p (scope))
7606 return build_nt (SCOPE_REF, scope, expr);
7608 if (!BASELINK_P (name) && !DECL_P (expr))
7610 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7611 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7612 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7614 if (complain & tf_error)
7616 error ("dependent-name %qE is parsed as a non-type, but "
7617 "instantiation yields a type", qualified_id);
7618 inform ("say %<typename %E%> if a type is meant", qualified_id);
7620 return error_mark_node;
7626 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7628 /* Remember that there was a reference to this entity. */
7632 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7634 if (complain & tf_error)
7635 qualified_name_lookup_error (scope,
7636 TREE_OPERAND (qualified_id, 1),
7638 return error_mark_node;
7642 expr = lookup_template_function (expr, template_args);
7644 if (expr == error_mark_node && complain & tf_error)
7645 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7647 else if (TYPE_P (scope))
7649 expr = (adjust_result_of_qualified_name_lookup
7650 (expr, scope, current_class_type));
7651 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7654 expr = convert_from_reference (expr);
7659 /* Like tsubst, but deals with expressions. This function just replaces
7660 template parms; to finish processing the resultant expression, use
7664 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7666 enum tree_code code;
7669 if (t == NULL_TREE || t == error_mark_node)
7672 code = TREE_CODE (t);
7677 r = retrieve_local_specialization (t);
7678 gcc_assert (r != NULL);
7687 if (DECL_TEMPLATE_PARM_P (t))
7688 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7689 /* There is no need to substitute into namespace-scope
7691 if (DECL_NAMESPACE_SCOPE_P (t))
7693 /* If ARGS is NULL, then T is known to be non-dependent. */
7694 if (args == NULL_TREE)
7695 return integral_constant_value (t);
7697 /* Unfortunately, we cannot just call lookup_name here.
7700 template <int I> int f() {
7702 struct S { void g() { E e = a; } };
7705 When we instantiate f<7>::S::g(), say, lookup_name is not
7706 clever enough to find f<7>::a. */
7708 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7709 /*entering_scope=*/0);
7711 for (v = TYPE_VALUES (enum_type);
7714 if (TREE_PURPOSE (v) == DECL_NAME (t))
7715 return TREE_VALUE (v);
7717 /* We didn't find the name. That should never happen; if
7718 name-lookup found it during preliminary parsing, we
7719 should find it again here during instantiation. */
7725 if (DECL_CONTEXT (t))
7729 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7730 /*entering_scope=*/1);
7731 if (ctx != DECL_CONTEXT (t))
7733 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7736 if (complain & tf_error)
7737 error ("using invalid field %qD", t);
7738 return error_mark_node;
7748 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7749 || local_variable_p (t))
7750 t = tsubst (t, args, complain, in_decl);
7755 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7758 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7759 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7760 args, complain, in_decl);
7761 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7762 return tsubst (t, args, complain, in_decl);
7763 else if (DECL_CLASS_SCOPE_P (t)
7764 && uses_template_parms (DECL_CONTEXT (t)))
7766 /* Template template argument like the following example need
7769 template <template <class> class TT> struct C {};
7770 template <class T> struct D {
7771 template <class U> struct E {};
7776 We are processing the template argument `E' in #1 for
7777 the template instantiation #2. Originally, `E' is a
7778 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7779 have to substitute this with one having context `D<int>'. */
7781 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7782 return lookup_field (context, DECL_NAME(t), 0, false);
7785 /* Ordinary template template argument. */
7789 case REINTERPRET_CAST_EXPR:
7790 case CONST_CAST_EXPR:
7791 case STATIC_CAST_EXPR:
7792 case DYNAMIC_CAST_EXPR:
7795 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7796 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7800 case TRUTH_NOT_EXPR:
7803 case UNARY_PLUS_EXPR: /* Unary + */
7812 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7813 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7820 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7821 name = TREE_OPERAND (t, 1);
7822 if (TREE_CODE (name) == BIT_NOT_EXPR)
7824 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7826 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7828 else if (TREE_CODE (name) == SCOPE_REF
7829 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7831 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7833 name = TREE_OPERAND (name, 1);
7834 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7836 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7837 name = build_nt (SCOPE_REF, base, name);
7839 else if (TREE_CODE (name) == BASELINK)
7840 name = tsubst_baselink (name,
7841 non_reference (TREE_TYPE (object)),
7845 name = tsubst_copy (name, args, complain, in_decl);
7846 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7852 case TRUNC_DIV_EXPR:
7854 case FLOOR_DIV_EXPR:
7855 case ROUND_DIV_EXPR:
7856 case EXACT_DIV_EXPR:
7860 case TRUNC_MOD_EXPR:
7861 case FLOOR_MOD_EXPR:
7862 case TRUTH_ANDIF_EXPR:
7863 case TRUTH_ORIF_EXPR:
7864 case TRUTH_AND_EXPR:
7882 case PREDECREMENT_EXPR:
7883 case PREINCREMENT_EXPR:
7884 case POSTDECREMENT_EXPR:
7885 case POSTINCREMENT_EXPR:
7887 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7888 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7893 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7894 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7895 NULL_TREE, NULL_TREE);
7898 return build_nt (code,
7899 tsubst_copy (TREE_OPERAND (t, 0), args,
7901 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7907 case PSEUDO_DTOR_EXPR:
7910 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7911 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7912 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7913 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7920 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7921 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7922 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7923 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7930 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7931 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7932 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7933 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7937 case TEMPLATE_ID_EXPR:
7939 /* Substituted template arguments */
7940 tree fn = TREE_OPERAND (t, 0);
7941 tree targs = TREE_OPERAND (t, 1);
7943 fn = tsubst_copy (fn, args, complain, in_decl);
7945 targs = tsubst_template_args (targs, args, complain, in_decl);
7947 return lookup_template_function (fn, targs);
7952 tree purpose, value, chain;
7954 if (t == void_list_node)
7957 purpose = TREE_PURPOSE (t);
7959 purpose = tsubst_copy (purpose, args, complain, in_decl);
7960 value = TREE_VALUE (t);
7962 value = tsubst_copy (value, args, complain, in_decl);
7963 chain = TREE_CHAIN (t);
7964 if (chain && chain != void_type_node)
7965 chain = tsubst_copy (chain, args, complain, in_decl);
7966 if (purpose == TREE_PURPOSE (t)
7967 && value == TREE_VALUE (t)
7968 && chain == TREE_CHAIN (t))
7970 return tree_cons (purpose, value, chain);
7977 case TEMPLATE_TYPE_PARM:
7978 case TEMPLATE_TEMPLATE_PARM:
7979 case BOUND_TEMPLATE_TEMPLATE_PARM:
7980 case TEMPLATE_PARM_INDEX:
7982 case REFERENCE_TYPE:
7988 case UNBOUND_CLASS_TEMPLATE:
7991 return tsubst (t, args, complain, in_decl);
7993 case IDENTIFIER_NODE:
7994 if (IDENTIFIER_TYPENAME_P (t))
7996 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7997 return mangle_conv_op_name_for_type (new_type);
8004 r = build_constructor
8005 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8006 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
8007 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8012 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8014 tsubst (TREE_TYPE (t), args, complain, in_decl));
8016 case CLEANUP_POINT_EXPR:
8017 /* We shouldn't have built any of these during initial template
8018 generation. Instead, they should be built during instantiation
8019 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8027 /* Like tsubst_copy for expressions, etc. but also does semantic
8031 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8035 if (t == NULL_TREE || t == error_mark_node)
8038 if (EXPR_HAS_LOCATION (t))
8039 input_location = EXPR_LOCATION (t);
8040 if (STATEMENT_CODE_P (TREE_CODE (t)))
8041 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8043 switch (TREE_CODE (t))
8045 case STATEMENT_LIST:
8047 tree_stmt_iterator i;
8048 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8049 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8053 case CTOR_INITIALIZER:
8054 finish_mem_initializers (tsubst_initializer_list
8055 (TREE_OPERAND (t, 0), args));
8059 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8060 args, complain, in_decl));
8064 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8065 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8066 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8068 finish_expr_stmt (tmp);
8072 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8073 args, complain, in_decl));
8081 decl = DECL_EXPR_DECL (t);
8082 if (TREE_CODE (decl) == LABEL_DECL)
8083 finish_label_decl (DECL_NAME (decl));
8084 else if (TREE_CODE (decl) == USING_DECL)
8086 tree scope = USING_DECL_SCOPE (decl);
8087 tree name = DECL_NAME (decl);
8090 scope = tsubst_expr (scope, args, complain, in_decl);
8091 decl = lookup_qualified_name (scope, name,
8092 /*is_type_p=*/false,
8093 /*complain=*/false);
8094 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8095 qualified_name_lookup_error (scope, name, decl);
8097 do_local_using_decl (decl, scope, name);
8101 init = DECL_INITIAL (decl);
8102 decl = tsubst (decl, args, complain, in_decl);
8103 if (decl != error_mark_node)
8106 DECL_INITIAL (decl) = error_mark_node;
8107 /* By marking the declaration as instantiated, we avoid
8108 trying to instantiate it. Since instantiate_decl can't
8109 handle local variables, and since we've already done
8110 all that needs to be done, that's the right thing to
8112 if (TREE_CODE (decl) == VAR_DECL)
8113 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8114 if (TREE_CODE (decl) == VAR_DECL
8115 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8116 /* Anonymous aggregates are a special case. */
8117 finish_anon_union (decl);
8120 maybe_push_decl (decl);
8121 if (TREE_CODE (decl) == VAR_DECL
8122 && DECL_PRETTY_FUNCTION_P (decl))
8124 /* For __PRETTY_FUNCTION__ we have to adjust the
8126 const char *const name
8127 = cxx_printable_name (current_function_decl, 2);
8128 init = cp_fname_init (name, &TREE_TYPE (decl));
8131 init = tsubst_expr (init, args, complain, in_decl);
8132 cp_finish_decl (decl, init, NULL_TREE, 0);
8137 /* A DECL_EXPR can also be used as an expression, in the condition
8138 clause of an if/for/while construct. */
8143 stmt = begin_for_stmt ();
8144 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8145 finish_for_init_stmt (stmt);
8146 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8147 finish_for_cond (tmp, stmt);
8148 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8149 finish_for_expr (tmp, stmt);
8150 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8151 finish_for_stmt (stmt);
8155 stmt = begin_while_stmt ();
8156 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8157 finish_while_stmt_cond (tmp, stmt);
8158 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8159 finish_while_stmt (stmt);
8163 stmt = begin_do_stmt ();
8164 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8165 finish_do_body (stmt);
8166 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8167 finish_do_stmt (tmp, stmt);
8171 stmt = begin_if_stmt ();
8172 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8173 finish_if_stmt_cond (tmp, stmt);
8174 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8175 finish_then_clause (stmt);
8177 if (ELSE_CLAUSE (t))
8179 begin_else_clause (stmt);
8180 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8181 finish_else_clause (stmt);
8184 finish_if_stmt (stmt);
8188 if (BIND_EXPR_BODY_BLOCK (t))
8189 stmt = begin_function_body ();
8191 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8192 ? BCS_TRY_BLOCK : 0);
8194 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8196 if (BIND_EXPR_BODY_BLOCK (t))
8197 finish_function_body (stmt);
8199 finish_compound_stmt (stmt);
8203 finish_break_stmt ();
8207 finish_continue_stmt ();
8211 stmt = begin_switch_stmt ();
8212 tmp = tsubst_expr (SWITCH_STMT_COND (t), args, complain, in_decl);
8213 finish_switch_cond (tmp, stmt);
8214 tsubst_expr (SWITCH_STMT_BODY (t), args, complain, in_decl);
8215 finish_switch_stmt (stmt);
8218 case CASE_LABEL_EXPR:
8219 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8220 tsubst_expr (CASE_HIGH (t), args, complain,
8225 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8229 tmp = GOTO_DESTINATION (t);
8230 if (TREE_CODE (tmp) != LABEL_DECL)
8231 /* Computed goto's must be tsubst'd into. On the other hand,
8232 non-computed gotos must not be; the identifier in question
8233 will have no binding. */
8234 tmp = tsubst_expr (tmp, args, complain, in_decl);
8236 tmp = DECL_NAME (tmp);
8237 finish_goto_stmt (tmp);
8241 tmp = finish_asm_stmt
8242 (ASM_VOLATILE_P (t),
8243 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8244 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8245 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8246 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8248 tree asm_expr = tmp;
8249 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8250 asm_expr = TREE_OPERAND (asm_expr, 0);
8251 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8258 stmt = begin_try_block ();
8259 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8260 finish_cleanup_try_block (stmt);
8261 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8267 if (FN_TRY_BLOCK_P (t))
8268 stmt = begin_function_try_block ();
8270 stmt = begin_try_block ();
8272 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8274 if (FN_TRY_BLOCK_P (t))
8275 finish_function_try_block (stmt);
8277 finish_try_block (stmt);
8279 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8280 if (FN_TRY_BLOCK_P (t))
8281 finish_function_handler_sequence (stmt);
8283 finish_handler_sequence (stmt);
8291 stmt = begin_handler ();
8292 if (HANDLER_PARMS (t))
8294 decl = HANDLER_PARMS (t);
8295 decl = tsubst (decl, args, complain, in_decl);
8296 /* Prevent instantiate_decl from trying to instantiate
8297 this variable. We've already done all that needs to be
8299 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8303 finish_handler_parms (decl, stmt);
8304 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8305 finish_handler (stmt);
8310 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8314 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8316 return tsubst_copy_and_build (t, args, complain, in_decl,
8317 /*function_p=*/false);
8323 /* T is a postfix-expression that is not being used in a function
8324 call. Return the substituted version of T. */
8327 tsubst_non_call_postfix_expression (tree t, tree args,
8328 tsubst_flags_t complain,
8331 if (TREE_CODE (t) == SCOPE_REF)
8332 t = tsubst_qualified_id (t, args, complain, in_decl,
8333 /*done=*/false, /*address_p=*/false);
8335 t = tsubst_copy_and_build (t, args, complain, in_decl,
8336 /*function_p=*/false);
8341 /* Like tsubst but deals with expressions and performs semantic
8342 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8345 tsubst_copy_and_build (tree t,
8347 tsubst_flags_t complain,
8351 #define RECUR(NODE) \
8352 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8356 if (t == NULL_TREE || t == error_mark_node)
8359 switch (TREE_CODE (t))
8364 case IDENTIFIER_NODE:
8368 tree qualifying_class;
8369 bool non_integral_constant_expression_p;
8370 const char *error_msg;
8372 if (IDENTIFIER_TYPENAME_P (t))
8374 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8375 t = mangle_conv_op_name_for_type (new_type);
8378 /* Look up the name. */
8379 decl = lookup_name (t, 0);
8381 /* By convention, expressions use ERROR_MARK_NODE to indicate
8382 failure, not NULL_TREE. */
8383 if (decl == NULL_TREE)
8384 decl = error_mark_node;
8386 decl = finish_id_expression (t, decl, NULL_TREE,
8389 /*integral_constant_expression_p=*/false,
8390 /*allow_non_integral_constant_expression_p=*/false,
8391 &non_integral_constant_expression_p,
8395 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8396 decl = unqualified_name_lookup_error (decl);
8400 case TEMPLATE_ID_EXPR:
8403 tree template = RECUR (TREE_OPERAND (t, 0));
8404 tree targs = TREE_OPERAND (t, 1);
8407 targs = tsubst_template_args (targs, args, complain, in_decl);
8409 if (TREE_CODE (template) == COMPONENT_REF)
8411 object = TREE_OPERAND (template, 0);
8412 template = TREE_OPERAND (template, 1);
8416 template = lookup_template_function (template, targs);
8419 return build3 (COMPONENT_REF, TREE_TYPE (template),
8420 object, template, NULL_TREE);
8427 tree r = RECUR (TREE_OPERAND (t, 0));
8429 if (REFERENCE_REF_P (t))
8431 /* A type conversion to reference type will be enclosed in
8432 such an indirect ref, but the substitution of the cast
8433 will have also added such an indirect ref. */
8434 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8435 r = convert_from_reference (r);
8438 r = build_x_indirect_ref (r, "unary *");
8444 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8445 RECUR (TREE_OPERAND (t, 0)));
8448 return build_functional_cast
8449 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8450 RECUR (TREE_OPERAND (t, 0)));
8452 case REINTERPRET_CAST_EXPR:
8453 return build_reinterpret_cast
8454 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8455 RECUR (TREE_OPERAND (t, 0)));
8457 case CONST_CAST_EXPR:
8458 return build_const_cast
8459 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8460 RECUR (TREE_OPERAND (t, 0)));
8462 case DYNAMIC_CAST_EXPR:
8463 return build_dynamic_cast
8464 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8465 RECUR (TREE_OPERAND (t, 0)));
8467 case STATIC_CAST_EXPR:
8468 return build_static_cast
8469 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8470 RECUR (TREE_OPERAND (t, 0)));
8472 case POSTDECREMENT_EXPR:
8473 case POSTINCREMENT_EXPR:
8474 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8475 args, complain, in_decl);
8476 return build_x_unary_op (TREE_CODE (t), op1);
8478 case PREDECREMENT_EXPR:
8479 case PREINCREMENT_EXPR:
8483 case TRUTH_NOT_EXPR:
8484 case UNARY_PLUS_EXPR: /* Unary + */
8487 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8490 op1 = TREE_OPERAND (t, 0);
8491 if (TREE_CODE (op1) == SCOPE_REF)
8492 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8493 /*done=*/true, /*address_p=*/true);
8495 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8497 if (TREE_CODE (op1) == LABEL_DECL)
8498 return finish_label_address_expr (DECL_NAME (op1));
8499 return build_x_unary_op (ADDR_EXPR, op1);
8504 case TRUNC_DIV_EXPR:
8506 case FLOOR_DIV_EXPR:
8507 case ROUND_DIV_EXPR:
8508 case EXACT_DIV_EXPR:
8512 case TRUNC_MOD_EXPR:
8513 case FLOOR_MOD_EXPR:
8514 case TRUTH_ANDIF_EXPR:
8515 case TRUTH_ORIF_EXPR:
8516 case TRUTH_AND_EXPR:
8532 return build_x_binary_op
8534 RECUR (TREE_OPERAND (t, 0)),
8535 RECUR (TREE_OPERAND (t, 1)),
8536 /*overloaded_p=*/NULL);
8539 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8540 /*address_p=*/false);
8542 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8543 args, complain, in_decl);
8544 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8545 /*overloaded_p=*/NULL);
8549 op1 = TREE_OPERAND (t, 0);
8552 /* When there are no ARGS, we are trying to evaluate a
8553 non-dependent expression from the parser. Trying to do
8554 the substitutions may not work. */
8556 op1 = TREE_TYPE (op1);
8565 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8567 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8571 tree r = build_x_modify_expr
8572 (RECUR (TREE_OPERAND (t, 0)),
8573 TREE_CODE (TREE_OPERAND (t, 1)),
8574 RECUR (TREE_OPERAND (t, 2)));
8575 /* TREE_NO_WARNING must be set if either the expression was
8576 parenthesized or it uses an operator such as >>= rather
8577 than plain assignment. In the former case, it was already
8578 set and must be copied. In the latter case,
8579 build_x_modify_expr sets it and it must not be reset
8581 if (TREE_NO_WARNING (t))
8582 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8587 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8588 args, complain, in_decl);
8589 /* Remember that there was a reference to this entity. */
8592 return build_x_arrow (op1);
8596 (RECUR (TREE_OPERAND (t, 0)),
8597 RECUR (TREE_OPERAND (t, 1)),
8598 RECUR (TREE_OPERAND (t, 2)),
8599 RECUR (TREE_OPERAND (t, 3)),
8600 NEW_EXPR_USE_GLOBAL (t));
8603 return delete_sanity
8604 (RECUR (TREE_OPERAND (t, 0)),
8605 RECUR (TREE_OPERAND (t, 1)),
8606 DELETE_EXPR_USE_VEC (t),
8607 DELETE_EXPR_USE_GLOBAL (t));
8610 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8611 RECUR (TREE_OPERAND (t, 1)));
8620 function = TREE_OPERAND (t, 0);
8621 /* When we parsed the expression, we determined whether or
8622 not Koenig lookup should be performed. */
8623 koenig_p = KOENIG_LOOKUP_P (t);
8624 if (TREE_CODE (function) == SCOPE_REF)
8627 function = tsubst_qualified_id (function, args, complain, in_decl,
8629 /*address_p=*/false);
8633 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8634 && (TREE_CODE (TREE_OPERAND (function, 1))
8636 function = tsubst_copy_and_build (function, args, complain,
8639 if (BASELINK_P (function))
8643 call_args = RECUR (TREE_OPERAND (t, 1));
8645 /* We do not perform argument-dependent lookup if normal
8646 lookup finds a non-function, in accordance with the
8647 expected resolution of DR 218. */
8649 && ((is_overloaded_fn (function)
8650 /* If lookup found a member function, the Koenig lookup is
8651 not appropriate, even if an unqualified-name was used
8652 to denote the function. */
8653 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8654 || TREE_CODE (function) == IDENTIFIER_NODE))
8655 function = perform_koenig_lookup (function, call_args);
8657 if (TREE_CODE (function) == IDENTIFIER_NODE)
8659 unqualified_name_lookup_error (function);
8660 return error_mark_node;
8663 /* Remember that there was a reference to this entity. */
8664 if (DECL_P (function))
8665 mark_used (function);
8667 if (TREE_CODE (function) == OFFSET_REF)
8668 return build_offset_ref_call_from_tree (function, call_args);
8669 if (TREE_CODE (function) == COMPONENT_REF)
8671 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8672 return finish_call_expr (function, call_args,
8673 /*disallow_virtual=*/false,
8674 /*koenig_p=*/false);
8676 return (build_new_method_call
8677 (TREE_OPERAND (function, 0),
8678 TREE_OPERAND (function, 1),
8679 call_args, NULL_TREE,
8680 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8682 return finish_call_expr (function, call_args,
8683 /*disallow_virtual=*/qualified_p,
8688 return build_x_conditional_expr
8689 (RECUR (TREE_OPERAND (t, 0)),
8690 RECUR (TREE_OPERAND (t, 1)),
8691 RECUR (TREE_OPERAND (t, 2)));
8693 case PSEUDO_DTOR_EXPR:
8694 return finish_pseudo_destructor_expr
8695 (RECUR (TREE_OPERAND (t, 0)),
8696 RECUR (TREE_OPERAND (t, 1)),
8697 RECUR (TREE_OPERAND (t, 2)));
8701 tree purpose, value, chain;
8703 if (t == void_list_node)
8706 purpose = TREE_PURPOSE (t);
8708 purpose = RECUR (purpose);
8709 value = TREE_VALUE (t);
8711 value = RECUR (value);
8712 chain = TREE_CHAIN (t);
8713 if (chain && chain != void_type_node)
8714 chain = RECUR (chain);
8715 if (purpose == TREE_PURPOSE (t)
8716 && value == TREE_VALUE (t)
8717 && chain == TREE_CHAIN (t))
8719 return tree_cons (purpose, value, chain);
8727 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8728 args, complain, in_decl);
8729 /* Remember that there was a reference to this entity. */
8730 if (DECL_P (object))
8733 member = TREE_OPERAND (t, 1);
8734 if (BASELINK_P (member))
8735 member = tsubst_baselink (member,
8736 non_reference (TREE_TYPE (object)),
8737 args, complain, in_decl);
8739 member = tsubst_copy (member, args, complain, in_decl);
8741 if (member == error_mark_node)
8742 return error_mark_node;
8743 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8745 if (TREE_CODE (member) == BIT_NOT_EXPR)
8746 return finish_pseudo_destructor_expr (object,
8748 TREE_TYPE (object));
8749 else if (TREE_CODE (member) == SCOPE_REF
8750 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8751 return finish_pseudo_destructor_expr (object,
8753 TREE_TYPE (object));
8755 else if (TREE_CODE (member) == SCOPE_REF
8756 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8761 /* Lookup the template functions now that we know what the
8763 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8764 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8765 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8766 /*is_type_p=*/false,
8767 /*complain=*/false);
8768 if (BASELINK_P (member))
8770 BASELINK_FUNCTIONS (member)
8771 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8773 member = (adjust_result_of_qualified_name_lookup
8774 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8775 TREE_TYPE (object)));
8779 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8781 return error_mark_node;
8784 else if (TREE_CODE (member) == SCOPE_REF
8785 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8786 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8788 if (complain & tf_error)
8790 if (TYPE_P (TREE_OPERAND (member, 0)))
8791 error ("%qT is not a class or namespace",
8792 TREE_OPERAND (member, 0));
8794 error ("%qD is not a class or namespace",
8795 TREE_OPERAND (member, 0));
8797 return error_mark_node;
8799 else if (TREE_CODE (member) == FIELD_DECL)
8800 return finish_non_static_data_member (member, object, NULL_TREE);
8802 return finish_class_member_access_expr (object, member);
8807 (RECUR (TREE_OPERAND (t, 0)));
8813 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8816 /* digest_init will do the wrong thing if we let it. */
8817 if (type && TYPE_PTRMEMFUNC_P (type))
8821 /* We do not want to process the purpose of aggregate
8822 initializers as they are identifier nodes which will be
8823 looked up by digest_init. */
8824 purpose_p = !(type && IS_AGGR_TYPE (type));
8825 for (elts = CONSTRUCTOR_ELTS (t);
8827 elts = TREE_CHAIN (elts))
8829 tree purpose = TREE_PURPOSE (elts);
8830 tree value = TREE_VALUE (elts);
8832 if (purpose && purpose_p)
8833 purpose = RECUR (purpose);
8834 value = RECUR (value);
8835 r = tree_cons (purpose, value, r);
8838 r = build_constructor (NULL_TREE, nreverse (r));
8839 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8842 return digest_init (type, r, 0);
8848 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8849 if (TYPE_P (operand_0))
8850 return get_typeid (operand_0);
8851 return build_typeid (operand_0);
8861 tree r = tsubst_copy (t, args, complain, in_decl);
8863 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8864 /* If the original type was a reference, we'll be wrapped in
8865 the appropriate INDIRECT_REF. */
8866 r = convert_from_reference (r);
8871 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8872 tsubst_copy (TREE_TYPE (t), args, complain,
8876 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8880 tree old_stmt_expr = cur_stmt_expr;
8881 tree stmt_expr = begin_stmt_expr ();
8883 cur_stmt_expr = stmt_expr;
8884 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8885 stmt_expr = finish_stmt_expr (stmt_expr, false);
8886 cur_stmt_expr = old_stmt_expr;
8892 t = tsubst_copy (t, args, complain, in_decl);
8893 /* As in finish_id_expression, we resolve enumeration constants
8894 to their underlying values. */
8895 if (TREE_CODE (t) == CONST_DECL)
8896 return DECL_INITIAL (t);
8900 /* Handle Objective-C++ constructs, if appropriate. */
8903 = objcp_tsubst_copy_and_build (t, args, complain,
8904 in_decl, /*function_p=*/false);
8908 return tsubst_copy (t, args, complain, in_decl);
8914 /* Verify that the instantiated ARGS are valid. For type arguments,
8915 make sure that the type's linkage is ok. For non-type arguments,
8916 make sure they are constants if they are integral or enumerations.
8917 Emit an error under control of COMPLAIN, and return TRUE on error. */
8920 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8922 int ix, len = DECL_NTPARMS (tmpl);
8923 bool result = false;
8924 bool error_p = complain & tf_error;
8926 for (ix = 0; ix != len; ix++)
8928 tree t = TREE_VEC_ELT (args, ix);
8932 /* [basic.link]: A name with no linkage (notably, the name
8933 of a class or enumeration declared in a local scope)
8934 shall not be used to declare an entity with linkage.
8935 This implies that names with no linkage cannot be used as
8936 template arguments. */
8937 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8941 if (TYPE_ANONYMOUS_P (nt))
8942 error ("%qT is/uses anonymous type", t);
8944 error ("%qT uses local type %qT", t, nt);
8948 /* In order to avoid all sorts of complications, we do not
8949 allow variably-modified types as template arguments. */
8950 else if (variably_modified_type_p (t, NULL_TREE))
8952 if (complain & tf_error)
8953 error ("%qT is a variably modified type", t);
8957 /* A non-type argument of integral or enumerated type must be a
8959 else if (TREE_TYPE (t)
8960 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8961 && !TREE_CONSTANT (t))
8963 if (complain & tf_error)
8964 error ("integral expression %qE is not constant", t);
8968 if (result && error_p)
8969 error (" trying to instantiate %qD", tmpl);
8973 /* Instantiate the indicated variable or function template TMPL with
8974 the template arguments in TARG_PTR. */
8977 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8983 if (tmpl == error_mark_node)
8984 return error_mark_node;
8986 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
8988 /* If this function is a clone, handle it specially. */
8989 if (DECL_CLONED_FUNCTION_P (tmpl))
8994 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8996 if (spec == error_mark_node)
8997 return error_mark_node;
8999 /* Look for the clone. */
9000 FOR_EACH_CLONE (clone, spec)
9001 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9003 /* We should always have found the clone by now. */
9008 /* Check to see if we already have this specialization. */
9009 spec = retrieve_specialization (tmpl, targ_ptr,
9010 /*class_specializations_p=*/false);
9011 if (spec != NULL_TREE)
9014 gen_tmpl = most_general_template (tmpl);
9015 if (tmpl != gen_tmpl)
9017 /* The TMPL is a partial instantiation. To get a full set of
9018 arguments we must add the arguments used to perform the
9019 partial instantiation. */
9020 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9023 /* Check to see if we already have this specialization. */
9024 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9025 /*class_specializations_p=*/false);
9026 if (spec != NULL_TREE)
9030 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9032 return error_mark_node;
9034 /* We are building a FUNCTION_DECL, during which the access of its
9035 parameters and return types have to be checked. However this
9036 FUNCTION_DECL which is the desired context for access checking
9037 is not built yet. We solve this chicken-and-egg problem by
9038 deferring all checks until we have the FUNCTION_DECL. */
9039 push_deferring_access_checks (dk_deferred);
9041 /* Substitute template parameters. */
9042 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9043 targ_ptr, complain, gen_tmpl);
9045 /* Now we know the specialization, compute access previously
9047 push_access_scope (fndecl);
9048 perform_deferred_access_checks ();
9049 pop_access_scope (fndecl);
9050 pop_deferring_access_checks ();
9052 /* The DECL_TI_TEMPLATE should always be the immediate parent
9053 template, not the most general template. */
9054 DECL_TI_TEMPLATE (fndecl) = tmpl;
9056 /* If we've just instantiated the main entry point for a function,
9057 instantiate all the alternate entry points as well. We do this
9058 by cloning the instantiation of the main entry point, not by
9059 instantiating the template clones. */
9060 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9061 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9066 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9067 arguments that are being used when calling it. TARGS is a vector
9068 into which the deduced template arguments are placed.
9070 Return zero for success, 2 for an incomplete match that doesn't resolve
9071 all the types, and 1 for complete failure. An error message will be
9072 printed only for an incomplete match.
9074 If FN is a conversion operator, or we are trying to produce a specific
9075 specialization, RETURN_TYPE is the return type desired.
9077 The EXPLICIT_TARGS are explicit template arguments provided via a
9080 The parameter STRICT is one of:
9083 We are deducing arguments for a function call, as in
9087 We are deducing arguments for a conversion function, as in
9091 We are deducing arguments when doing an explicit instantiation
9092 as in [temp.explicit], when determining an explicit specialization
9093 as in [temp.expl.spec], or when taking the address of a function
9094 template, as in [temp.deduct.funcaddr]. */
9097 fn_type_unification (tree fn,
9098 tree explicit_targs,
9102 unification_kind_t strict)
9108 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9110 fntype = TREE_TYPE (fn);
9115 The specified template arguments must match the template
9116 parameters in kind (i.e., type, nontype, template), and there
9117 must not be more arguments than there are parameters;
9118 otherwise type deduction fails.
9120 Nontype arguments must match the types of the corresponding
9121 nontype template parameters, or must be convertible to the
9122 types of the corresponding nontype parameters as specified in
9123 _temp.arg.nontype_, otherwise type deduction fails.
9125 All references in the function type of the function template
9126 to the corresponding template parameters are replaced by the
9127 specified template argument values. If a substitution in a
9128 template parameter or in the function type of the function
9129 template results in an invalid type, type deduction fails. */
9131 tree converted_args;
9134 if (explicit_targs == error_mark_node)
9138 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9139 explicit_targs, NULL_TREE, tf_none,
9140 /*require_all_arguments=*/0));
9141 if (converted_args == error_mark_node)
9144 /* Substitute the explicit args into the function type. This is
9145 necessary so that, for instance, explicitly declared function
9146 arguments can match null pointed constants. If we were given
9147 an incomplete set of explicit args, we must not do semantic
9148 processing during substitution as we could create partial
9150 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9151 processing_template_decl += incomplete;
9152 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9153 processing_template_decl -= incomplete;
9155 if (fntype == error_mark_node)
9158 /* Place the explicitly specified arguments in TARGS. */
9159 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9160 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9163 parms = TYPE_ARG_TYPES (fntype);
9164 /* Never do unification on the 'this' parameter. */
9165 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9166 parms = TREE_CHAIN (parms);
9170 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9171 args = tree_cons (NULL_TREE, return_type, args);
9174 /* We allow incomplete unification without an error message here
9175 because the standard doesn't seem to explicitly prohibit it. Our
9176 callers must be ready to deal with unification failures in any
9178 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9179 targs, parms, args, /*subr=*/0,
9183 /* All is well so far. Now, check:
9187 When all template arguments have been deduced, all uses of
9188 template parameters in nondeduced contexts are replaced with
9189 the corresponding deduced argument values. If the
9190 substitution results in an invalid type, as described above,
9191 type deduction fails. */
9192 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9199 /* Adjust types before performing type deduction, as described in
9200 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9201 sections are symmetric. PARM is the type of a function parameter
9202 or the return type of the conversion function. ARG is the type of
9203 the argument passed to the call, or the type of the value
9204 initialized with the result of the conversion function. */
9207 maybe_adjust_types_for_deduction (unification_kind_t strict,
9220 /* Swap PARM and ARG throughout the remainder of this
9221 function; the handling is precisely symmetric since PARM
9222 will initialize ARG rather than vice versa. */
9230 /* There is nothing to do in this case. */
9237 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9239 /* [temp.deduct.call]
9241 If P is not a reference type:
9243 --If A is an array type, the pointer type produced by the
9244 array-to-pointer standard conversion (_conv.array_) is
9245 used in place of A for type deduction; otherwise,
9247 --If A is a function type, the pointer type produced by
9248 the function-to-pointer standard conversion
9249 (_conv.func_) is used in place of A for type deduction;
9252 --If A is a cv-qualified type, the top level
9253 cv-qualifiers of A's type are ignored for type
9255 if (TREE_CODE (*arg) == ARRAY_TYPE)
9256 *arg = build_pointer_type (TREE_TYPE (*arg));
9257 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9258 *arg = build_pointer_type (*arg);
9260 *arg = TYPE_MAIN_VARIANT (*arg);
9263 /* [temp.deduct.call]
9265 If P is a cv-qualified type, the top level cv-qualifiers
9266 of P's type are ignored for type deduction. If P is a
9267 reference type, the type referred to by P is used for
9269 *parm = TYPE_MAIN_VARIANT (*parm);
9270 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9272 *parm = TREE_TYPE (*parm);
9273 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9276 /* DR 322. For conversion deduction, remove a reference type on parm
9277 too (which has been swapped into ARG). */
9278 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9279 *arg = TREE_TYPE (*arg);
9284 /* Most parms like fn_type_unification.
9286 If SUBR is 1, we're being called recursively (to unify the
9287 arguments of a function or method parameter of a function
9288 template). If IS_METHOD is true, XPARMS are the parms of a
9289 member function, and special rules apply to cv qualification
9290 deduction on the this parameter. */
9293 type_unification_real (tree tparms,
9298 unification_kind_t strict,
9303 int ntparms = TREE_VEC_LENGTH (tparms);
9305 int saw_undeduced = 0;
9308 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9309 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9310 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9311 gcc_assert (ntparms > 0);
9316 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9317 | UNIFY_ALLOW_DERIVED);
9321 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9325 sub_strict = UNIFY_ALLOW_NONE;
9336 while (parms && parms != void_list_node
9337 && args && args != void_list_node)
9339 parm = TREE_VALUE (parms);
9340 parms = TREE_CHAIN (parms);
9341 arg = TREE_VALUE (args);
9342 args = TREE_CHAIN (args);
9344 if (arg == error_mark_node)
9346 if (arg == unknown_type_node)
9347 /* We can't deduce anything from this, but we might get all the
9348 template args from other function args. */
9353 /* The cv qualifiers on the this pointer argument must match
9354 exactly. We cannot deduce a T as const X against a const
9355 member function for instance. */
9356 gcc_assert (TREE_CODE (parm) == POINTER_TYPE);
9357 gcc_assert (TREE_CODE (arg) == POINTER_TYPE);
9358 /* The restrict qualifier will be on the pointer. */
9359 if (cp_type_quals (parm) != cp_type_quals (arg))
9361 parm = TREE_TYPE (parm);
9362 arg = TREE_TYPE (arg);
9363 if (cp_type_quals (parm) != cp_type_quals (arg))
9366 parm = TYPE_MAIN_VARIANT (parm);
9367 arg = TYPE_MAIN_VARIANT (arg);
9371 /* Conversions will be performed on a function argument that
9372 corresponds with a function parameter that contains only
9373 non-deducible template parameters and explicitly specified
9374 template parameters. */
9375 if (!uses_template_parms (parm))
9380 type = TREE_TYPE (arg);
9384 if (same_type_p (parm, type))
9386 if (strict != DEDUCE_EXACT
9387 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg))
9395 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9396 if (type_unknown_p (arg))
9398 /* [temp.deduct.type] A template-argument can be deduced from
9399 a pointer to function or pointer to member function
9400 argument if the set of overloaded functions does not
9401 contain function templates and at most one of a set of
9402 overloaded functions provides a unique match. */
9404 if (resolve_overloaded_unification
9405 (tparms, targs, parm, arg, strict, sub_strict)
9410 arg = TREE_TYPE (arg);
9411 if (arg == error_mark_node)
9416 int arg_strict = sub_strict;
9419 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9421 if (unify (tparms, targs, parm, arg, arg_strict))
9426 /* Fail if we've reached the end of the parm list, and more args
9427 are present, and the parm list isn't variadic. */
9428 if (args && args != void_list_node && parms == void_list_node)
9430 /* Fail if parms are left and they don't have default values. */
9431 if (parms && parms != void_list_node
9432 && TREE_PURPOSE (parms) == NULL_TREE)
9436 for (i = 0; i < ntparms; i++)
9437 if (!TREE_VEC_ELT (targs, i))
9439 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9441 /* If this is an undeduced nontype parameter that depends on
9442 a type parameter, try another pass; its type may have been
9443 deduced from a later argument than the one from which
9444 this parameter can be deduced. */
9445 if (TREE_CODE (tparm) == PARM_DECL
9446 && uses_template_parms (TREE_TYPE (tparm))
9447 && !saw_undeduced++)
9456 /* Subroutine of type_unification_real. Args are like the variables at the
9457 call site. ARG is an overloaded function (or template-id); we try
9458 deducing template args from each of the overloads, and if only one
9459 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9462 resolve_overloaded_unification (tree tparms,
9466 unification_kind_t strict,
9469 tree tempargs = copy_node (targs);
9473 if (TREE_CODE (arg) == ADDR_EXPR)
9475 arg = TREE_OPERAND (arg, 0);
9481 if (TREE_CODE (arg) == COMPONENT_REF)
9482 /* Handle `&x' where `x' is some static or non-static member
9484 arg = TREE_OPERAND (arg, 1);
9486 if (TREE_CODE (arg) == OFFSET_REF)
9487 arg = TREE_OPERAND (arg, 1);
9489 /* Strip baselink information. */
9490 if (BASELINK_P (arg))
9491 arg = BASELINK_FUNCTIONS (arg);
9493 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9495 /* If we got some explicit template args, we need to plug them into
9496 the affected templates before we try to unify, in case the
9497 explicit args will completely resolve the templates in question. */
9499 tree expl_subargs = TREE_OPERAND (arg, 1);
9500 arg = TREE_OPERAND (arg, 0);
9502 for (; arg; arg = OVL_NEXT (arg))
9504 tree fn = OVL_CURRENT (arg);
9507 if (TREE_CODE (fn) != TEMPLATE_DECL)
9510 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9511 expl_subargs, /*check_ret=*/false);
9514 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9515 good += try_one_overload (tparms, targs, tempargs, parm,
9516 elem, strict, sub_strict, addr_p);
9522 gcc_assert (TREE_CODE (arg) == OVERLOAD
9523 || TREE_CODE (arg) == FUNCTION_DECL);
9525 for (; arg; arg = OVL_NEXT (arg))
9526 good += try_one_overload (tparms, targs, tempargs, parm,
9527 TREE_TYPE (OVL_CURRENT (arg)),
9528 strict, sub_strict, addr_p);
9531 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9532 to function or pointer to member function argument if the set of
9533 overloaded functions does not contain function templates and at most
9534 one of a set of overloaded functions provides a unique match.
9536 So if we found multiple possibilities, we return success but don't
9541 int i = TREE_VEC_LENGTH (targs);
9543 if (TREE_VEC_ELT (tempargs, i))
9544 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9552 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9553 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9554 different overloads deduce different arguments for a given parm.
9555 ADDR_P is true if the expression for which deduction is being
9556 performed was of the form "& fn" rather than simply "fn".
9558 Returns 1 on success. */
9561 try_one_overload (tree tparms,
9566 unification_kind_t strict,
9574 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9575 to function or pointer to member function argument if the set of
9576 overloaded functions does not contain function templates and at most
9577 one of a set of overloaded functions provides a unique match.
9579 So if this is a template, just return success. */
9581 if (uses_template_parms (arg))
9584 if (TREE_CODE (arg) == METHOD_TYPE)
9585 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9587 arg = build_pointer_type (arg);
9589 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9591 /* We don't copy orig_targs for this because if we have already deduced
9592 some template args from previous args, unify would complain when we
9593 try to deduce a template parameter for the same argument, even though
9594 there isn't really a conflict. */
9595 nargs = TREE_VEC_LENGTH (targs);
9596 tempargs = make_tree_vec (nargs);
9598 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9601 /* First make sure we didn't deduce anything that conflicts with
9602 explicitly specified args. */
9603 for (i = nargs; i--; )
9605 tree elt = TREE_VEC_ELT (tempargs, i);
9606 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9610 else if (uses_template_parms (elt))
9611 /* Since we're unifying against ourselves, we will fill in
9612 template args used in the function parm list with our own
9613 template parms. Discard them. */
9614 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9615 else if (oldelt && !template_args_equal (oldelt, elt))
9619 for (i = nargs; i--; )
9621 tree elt = TREE_VEC_ELT (tempargs, i);
9624 TREE_VEC_ELT (targs, i) = elt;
9630 /* Verify that nondeduce template argument agrees with the type
9631 obtained from argument deduction. Return nonzero if the
9636 struct A { typedef int X; };
9637 template <class T, class U> struct C {};
9638 template <class T> struct C<T, typename T::X> {};
9640 Then with the instantiation `C<A, int>', we can deduce that
9641 `T' is `A' but unify () does not check whether `typename T::X'
9642 is `int'. This function ensure that they agree.
9644 TARGS, PARMS are the same as the arguments of unify.
9645 ARGS contains template arguments from all levels. */
9648 verify_class_unification (tree targs, tree parms, tree args)
9650 parms = tsubst (parms, add_outermost_template_args (args, targs),
9651 tf_none, NULL_TREE);
9652 if (parms == error_mark_node)
9655 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9658 /* PARM is a template class (perhaps with unbound template
9659 parameters). ARG is a fully instantiated type. If ARG can be
9660 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9661 TARGS are as for unify. */
9664 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9668 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9669 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9670 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9673 /* We need to make a new template argument vector for the call to
9674 unify. If we used TARGS, we'd clutter it up with the result of
9675 the attempted unification, even if this class didn't work out.
9676 We also don't want to commit ourselves to all the unifications
9677 we've already done, since unification is supposed to be done on
9678 an argument-by-argument basis. In other words, consider the
9679 following pathological case:
9681 template <int I, int J, int K>
9684 template <int I, int J>
9685 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9687 template <int I, int J, int K>
9688 void f(S<I, J, K>, S<I, I, I>);
9697 Now, by the time we consider the unification involving `s2', we
9698 already know that we must have `f<0, 0, 0>'. But, even though
9699 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9700 because there are two ways to unify base classes of S<0, 1, 2>
9701 with S<I, I, I>. If we kept the already deduced knowledge, we
9702 would reject the possibility I=1. */
9703 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9705 /* If unification failed, we're done. */
9706 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9707 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9713 /* Given a template type PARM and a class type ARG, find the unique
9714 base type in ARG that is an instance of PARM. We do not examine
9715 ARG itself; only its base-classes. If there is not exactly one
9716 appropriate base class, return NULL_TREE. PARM may be the type of
9717 a partial specialization, as well as a plain template type. Used
9721 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9723 tree rval = NULL_TREE;
9726 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9728 binfo = TYPE_BINFO (complete_type (arg));
9730 /* The type could not be completed. */
9733 /* Walk in inheritance graph order. The search order is not
9734 important, and this avoids multiple walks of virtual bases. */
9735 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9737 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9741 /* If there is more than one satisfactory baseclass, then:
9745 If they yield more than one possible deduced A, the type
9749 if (rval && !same_type_p (r, rval))
9759 /* Returns the level of DECL, which declares a template parameter. */
9762 template_decl_level (tree decl)
9764 switch (TREE_CODE (decl))
9768 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9771 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9779 /* Decide whether ARG can be unified with PARM, considering only the
9780 cv-qualifiers of each type, given STRICT as documented for unify.
9781 Returns nonzero iff the unification is OK on that basis. */
9784 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9786 int arg_quals = cp_type_quals (arg);
9787 int parm_quals = cp_type_quals (parm);
9789 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9790 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9792 /* Although a CVR qualifier is ignored when being applied to a
9793 substituted template parameter ([8.3.2]/1 for example), that
9794 does not apply during deduction [14.8.2.4]/1, (even though
9795 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9796 this). Except when we're allowing additional CV qualifiers
9797 at the outer level [14.8.2.1]/3,1st bullet. */
9798 if ((TREE_CODE (arg) == REFERENCE_TYPE
9799 || TREE_CODE (arg) == FUNCTION_TYPE
9800 || TREE_CODE (arg) == METHOD_TYPE)
9801 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9804 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9805 && (parm_quals & TYPE_QUAL_RESTRICT))
9809 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9810 && (arg_quals & parm_quals) != parm_quals)
9813 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9814 && (parm_quals & arg_quals) != arg_quals)
9820 /* Takes parameters as for type_unification. Returns 0 if the
9821 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9822 bitwise or of the following flags:
9825 Require an exact match between PARM and ARG.
9826 UNIFY_ALLOW_MORE_CV_QUAL:
9827 Allow the deduced ARG to be more cv-qualified (by qualification
9828 conversion) than ARG.
9829 UNIFY_ALLOW_LESS_CV_QUAL:
9830 Allow the deduced ARG to be less cv-qualified than ARG.
9831 UNIFY_ALLOW_DERIVED:
9832 Allow the deduced ARG to be a template base class of ARG,
9833 or a pointer to a template base class of the type pointed to by
9835 UNIFY_ALLOW_INTEGER:
9836 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9837 case for more information.
9838 UNIFY_ALLOW_OUTER_LEVEL:
9839 This is the outermost level of a deduction. Used to determine validity
9840 of qualification conversions. A valid qualification conversion must
9841 have const qualified pointers leading up to the inner type which
9842 requires additional CV quals, except at the outer level, where const
9843 is not required [conv.qual]. It would be normal to set this flag in
9844 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9845 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9846 This is the outermost level of a deduction, and PARM can be more CV
9847 qualified at this point.
9848 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9849 This is the outermost level of a deduction, and PARM can be less CV
9850 qualified at this point. */
9853 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9858 int strict_in = strict;
9860 /* I don't think this will do the right thing with respect to types.
9861 But the only case I've seen it in so far has been array bounds, where
9862 signedness is the only information lost, and I think that will be
9864 while (TREE_CODE (parm) == NOP_EXPR)
9865 parm = TREE_OPERAND (parm, 0);
9867 if (arg == error_mark_node)
9869 if (arg == unknown_type_node)
9870 /* We can't deduce anything from this, but we might get all the
9871 template args from other function args. */
9874 /* If PARM uses template parameters, then we can't bail out here,
9875 even if ARG == PARM, since we won't record unifications for the
9876 template parameters. We might need them if we're trying to
9877 figure out which of two things is more specialized. */
9878 if (arg == parm && !uses_template_parms (parm))
9881 /* Immediately reject some pairs that won't unify because of
9882 cv-qualification mismatches. */
9883 if (TREE_CODE (arg) == TREE_CODE (parm)
9885 /* It is the elements of the array which hold the cv quals of an array
9886 type, and the elements might be template type parms. We'll check
9888 && TREE_CODE (arg) != ARRAY_TYPE
9889 /* We check the cv-qualifiers when unifying with template type
9890 parameters below. We want to allow ARG `const T' to unify with
9891 PARM `T' for example, when computing which of two templates
9892 is more specialized, for example. */
9893 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9894 && !check_cv_quals_for_unify (strict_in, arg, parm))
9897 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9898 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9899 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9900 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9901 strict &= ~UNIFY_ALLOW_DERIVED;
9902 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9903 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9905 switch (TREE_CODE (parm))
9909 case UNBOUND_CLASS_TEMPLATE:
9910 /* In a type which contains a nested-name-specifier, template
9911 argument values cannot be deduced for template parameters used
9912 within the nested-name-specifier. */
9915 case TEMPLATE_TYPE_PARM:
9916 case TEMPLATE_TEMPLATE_PARM:
9917 case BOUND_TEMPLATE_TEMPLATE_PARM:
9918 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9920 if (TEMPLATE_TYPE_LEVEL (parm)
9921 != template_decl_level (tparm))
9922 /* The PARM is not one we're trying to unify. Just check
9923 to see if it matches ARG. */
9924 return (TREE_CODE (arg) == TREE_CODE (parm)
9925 && same_type_p (parm, arg)) ? 0 : 1;
9926 idx = TEMPLATE_TYPE_IDX (parm);
9927 targ = TREE_VEC_ELT (targs, idx);
9928 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9930 /* Check for mixed types and values. */
9931 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9932 && TREE_CODE (tparm) != TYPE_DECL)
9933 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9934 && TREE_CODE (tparm) != TEMPLATE_DECL))
9937 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9939 /* ARG must be constructed from a template class or a template
9940 template parameter. */
9941 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9942 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9946 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9947 tree parmvec = TYPE_TI_ARGS (parm);
9948 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9950 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9953 /* The parameter and argument roles have to be switched here
9954 in order to handle default arguments properly. For example,
9955 template<template <class> class TT> void f(TT<int>)
9956 should be able to accept vector<int> which comes from
9957 template <class T, class Allocator = allocator>
9960 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9964 /* Deduce arguments T, i from TT<T> or TT<i>.
9965 We check each element of PARMVEC and ARGVEC individually
9966 rather than the whole TREE_VEC since they can have
9967 different number of elements. */
9969 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9971 if (unify (tparms, targs,
9972 TREE_VEC_ELT (parmvec, i),
9973 TREE_VEC_ELT (argvec, i),
9978 arg = TYPE_TI_TEMPLATE (arg);
9980 /* Fall through to deduce template name. */
9983 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9984 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9986 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9988 /* Simple cases: Value already set, does match or doesn't. */
9989 if (targ != NULL_TREE && template_args_equal (targ, arg))
9996 /* If PARM is `const T' and ARG is only `int', we don't have
9997 a match unless we are allowing additional qualification.
9998 If ARG is `const int' and PARM is just `T' that's OK;
9999 that binds `const int' to `T'. */
10000 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10004 /* Consider the case where ARG is `const volatile int' and
10005 PARM is `const T'. Then, T should be `volatile int'. */
10006 arg = cp_build_qualified_type_real
10007 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10008 if (arg == error_mark_node)
10011 /* Simple cases: Value already set, does match or doesn't. */
10012 if (targ != NULL_TREE && same_type_p (targ, arg))
10017 /* Make sure that ARG is not a variable-sized array. (Note
10018 that were talking about variable-sized arrays (like
10019 `int[n]'), rather than arrays of unknown size (like
10020 `int[]').) We'll get very confused by such a type since
10021 the bound of the array will not be computable in an
10022 instantiation. Besides, such types are not allowed in
10023 ISO C++, so we can do as we please here. */
10024 if (variably_modified_type_p (arg, NULL_TREE))
10028 TREE_VEC_ELT (targs, idx) = arg;
10031 case TEMPLATE_PARM_INDEX:
10032 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10034 if (TEMPLATE_PARM_LEVEL (parm)
10035 != template_decl_level (tparm))
10036 /* The PARM is not one we're trying to unify. Just check
10037 to see if it matches ARG. */
10038 return !(TREE_CODE (arg) == TREE_CODE (parm)
10039 && cp_tree_equal (parm, arg));
10041 idx = TEMPLATE_PARM_IDX (parm);
10042 targ = TREE_VEC_ELT (targs, idx);
10045 return !cp_tree_equal (targ, arg);
10047 /* [temp.deduct.type] If, in the declaration of a function template
10048 with a non-type template-parameter, the non-type
10049 template-parameter is used in an expression in the function
10050 parameter-list and, if the corresponding template-argument is
10051 deduced, the template-argument type shall match the type of the
10052 template-parameter exactly, except that a template-argument
10053 deduced from an array bound may be of any integral type.
10054 The non-type parameter might use already deduced type parameters. */
10055 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10056 if (!TREE_TYPE (arg))
10057 /* Template-parameter dependent expression. Just accept it for now.
10058 It will later be processed in convert_template_argument. */
10060 else if (same_type_p (TREE_TYPE (arg), tparm))
10062 else if ((strict & UNIFY_ALLOW_INTEGER)
10063 && (TREE_CODE (tparm) == INTEGER_TYPE
10064 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10065 /* Convert the ARG to the type of PARM; the deduced non-type
10066 template argument must exactly match the types of the
10067 corresponding parameter. */
10068 arg = fold (build_nop (TREE_TYPE (parm), arg));
10069 else if (uses_template_parms (tparm))
10070 /* We haven't deduced the type of this parameter yet. Try again
10076 TREE_VEC_ELT (targs, idx) = arg;
10081 /* A pointer-to-member constant can be unified only with
10082 another constant. */
10083 if (TREE_CODE (arg) != PTRMEM_CST)
10086 /* Just unify the class member. It would be useless (and possibly
10087 wrong, depending on the strict flags) to unify also
10088 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10089 arg refer to the same variable, even if through different
10090 classes. For instance:
10092 struct A { int x; };
10095 Unification of &A::x and &B::x must succeed. */
10096 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10097 PTRMEM_CST_MEMBER (arg), strict);
10102 if (TREE_CODE (arg) != POINTER_TYPE)
10105 /* [temp.deduct.call]
10107 A can be another pointer or pointer to member type that can
10108 be converted to the deduced A via a qualification
10109 conversion (_conv.qual_).
10111 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10112 This will allow for additional cv-qualification of the
10113 pointed-to types if appropriate. */
10115 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10116 /* The derived-to-base conversion only persists through one
10117 level of pointers. */
10118 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10120 return unify (tparms, targs, TREE_TYPE (parm),
10121 TREE_TYPE (arg), strict);
10124 case REFERENCE_TYPE:
10125 if (TREE_CODE (arg) != REFERENCE_TYPE)
10127 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10128 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10131 if (TREE_CODE (arg) != ARRAY_TYPE)
10133 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10134 != (TYPE_DOMAIN (arg) == NULL_TREE))
10136 if (TYPE_DOMAIN (parm) != NULL_TREE)
10141 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10142 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10144 /* Our representation of array types uses "N - 1" as the
10145 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10146 not an integer constant. */
10147 if (TREE_CODE (parm_max) == MINUS_EXPR)
10149 arg_max = fold_build2 (PLUS_EXPR,
10152 TREE_OPERAND (parm_max, 1));
10153 parm_max = TREE_OPERAND (parm_max, 0);
10156 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10159 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10160 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10167 case ENUMERAL_TYPE:
10169 if (TREE_CODE (arg) != TREE_CODE (parm))
10172 /* We have already checked cv-qualification at the top of the
10174 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10177 /* As far as unification is concerned, this wins. Later checks
10178 will invalidate it if necessary. */
10181 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10182 /* Type INTEGER_CST can come from ordinary constant template args. */
10184 while (TREE_CODE (arg) == NOP_EXPR)
10185 arg = TREE_OPERAND (arg, 0);
10187 if (TREE_CODE (arg) != INTEGER_CST)
10189 return !tree_int_cst_equal (parm, arg);
10194 if (TREE_CODE (arg) != TREE_VEC)
10196 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10198 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10199 if (unify (tparms, targs,
10200 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10208 if (TREE_CODE (arg) != TREE_CODE (parm))
10211 if (TYPE_PTRMEMFUNC_P (parm))
10213 if (!TYPE_PTRMEMFUNC_P (arg))
10216 return unify (tparms, targs,
10217 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10218 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10222 if (CLASSTYPE_TEMPLATE_INFO (parm))
10224 tree t = NULL_TREE;
10226 if (strict_in & UNIFY_ALLOW_DERIVED)
10228 /* First, we try to unify the PARM and ARG directly. */
10229 t = try_class_unification (tparms, targs,
10234 /* Fallback to the special case allowed in
10235 [temp.deduct.call]:
10237 If P is a class, and P has the form
10238 template-id, then A can be a derived class of
10239 the deduced A. Likewise, if P is a pointer to
10240 a class of the form template-id, A can be a
10241 pointer to a derived class pointed to by the
10243 t = get_template_base (tparms, targs, parm, arg);
10249 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10250 && (CLASSTYPE_TI_TEMPLATE (parm)
10251 == CLASSTYPE_TI_TEMPLATE (arg)))
10252 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10253 Then, we should unify `int' and `U'. */
10256 /* There's no chance of unification succeeding. */
10259 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10260 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10262 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10267 case FUNCTION_TYPE:
10268 if (TREE_CODE (arg) != TREE_CODE (parm))
10271 if (unify (tparms, targs, TREE_TYPE (parm),
10272 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10274 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10275 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10276 TREE_CODE (parm) == METHOD_TYPE);
10279 /* Unify a pointer to member with a pointer to member function, which
10280 deduces the type of the member as a function type. */
10281 if (TYPE_PTRMEMFUNC_P (arg))
10285 cp_cv_quals cv_quals;
10287 /* Check top-level cv qualifiers */
10288 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10291 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10292 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10295 /* Determine the type of the function we are unifying against. */
10296 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10298 build_function_type (TREE_TYPE (method_type),
10299 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10301 /* Extract the cv-qualifiers of the member function from the
10302 implicit object parameter and place them on the function
10303 type to be restored later. */
10305 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10306 fntype = build_qualified_type (fntype, cv_quals);
10307 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10310 if (TREE_CODE (arg) != OFFSET_TYPE)
10312 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10313 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10315 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10319 if (DECL_TEMPLATE_PARM_P (parm))
10320 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10321 if (arg != integral_constant_value (parm))
10326 case TEMPLATE_DECL:
10327 /* Matched cases are handled by the ARG == PARM test above. */
10331 gcc_assert (EXPR_P (parm));
10333 /* We must be looking at an expression. This can happen with
10337 void foo(S<I>, S<I + 2>);
10339 This is a "nondeduced context":
10343 The nondeduced contexts are:
10345 --A type that is a template-id in which one or more of
10346 the template-arguments is an expression that references
10347 a template-parameter.
10349 In these cases, we assume deduction succeeded, but don't
10350 actually infer any unifications. */
10352 if (!uses_template_parms (parm)
10353 && !template_args_equal (parm, arg))
10360 /* Note that DECL can be defined in this translation unit, if
10364 mark_definable (tree decl)
10367 DECL_NOT_REALLY_EXTERN (decl) = 1;
10368 FOR_EACH_CLONE (clone, decl)
10369 DECL_NOT_REALLY_EXTERN (clone) = 1;
10372 /* Called if RESULT is explicitly instantiated, or is a member of an
10373 explicitly instantiated class. */
10376 mark_decl_instantiated (tree result, int extern_p)
10378 SET_DECL_EXPLICIT_INSTANTIATION (result);
10380 /* If this entity has already been written out, it's too late to
10381 make any modifications. */
10382 if (TREE_ASM_WRITTEN (result))
10385 if (TREE_CODE (result) != FUNCTION_DECL)
10386 /* The TREE_PUBLIC flag for function declarations will have been
10387 set correctly by tsubst. */
10388 TREE_PUBLIC (result) = 1;
10390 /* This might have been set by an earlier implicit instantiation. */
10391 DECL_COMDAT (result) = 0;
10394 DECL_NOT_REALLY_EXTERN (result) = 0;
10397 mark_definable (result);
10398 /* Always make artificials weak. */
10399 if (DECL_ARTIFICIAL (result) && flag_weak)
10400 comdat_linkage (result);
10401 /* For WIN32 we also want to put explicit instantiations in
10402 linkonce sections. */
10403 else if (TREE_PUBLIC (result))
10404 maybe_make_one_only (result);
10407 /* If EXTERN_P, then this function will not be emitted -- unless
10408 followed by an explicit instantiation, at which point its linkage
10409 will be adjusted. If !EXTERN_P, then this function will be
10410 emitted here. In neither circumstance do we want
10411 import_export_decl to adjust the linkage. */
10412 DECL_INTERFACE_KNOWN (result) = 1;
10415 /* Given two function templates PAT1 and PAT2, return:
10417 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10418 -1 if PAT2 is more specialized than PAT1.
10419 0 if neither is more specialized.
10421 LEN indicates the number of parameters we should consider
10422 (defaulted parameters should not be considered).
10424 The 1998 std underspecified function template partial ordering, and
10425 DR214 addresses the issue. We take pairs of arguments, one from
10426 each of the templates, and deduce them against each other. One of
10427 the templates will be more specialized if all the *other*
10428 template's arguments deduce against its arguments and at least one
10429 of its arguments *does* *not* deduce against the other template's
10430 corresponding argument. Deduction is done as for class templates.
10431 The arguments used in deduction have reference and top level cv
10432 qualifiers removed. Iff both arguments were originally reference
10433 types *and* deduction succeeds in both directions, the template
10434 with the more cv-qualified argument wins for that pairing (if
10435 neither is more cv-qualified, they both are equal). Unlike regular
10436 deduction, after all the arguments have been deduced in this way,
10437 we do *not* verify the deduced template argument values can be
10438 substituted into non-deduced contexts, nor do we have to verify
10439 that all template arguments have been deduced. */
10442 more_specialized_fn (tree pat1, tree pat2, int len)
10444 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10445 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10446 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10447 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10448 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10449 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10450 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10451 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10455 /* If only one is a member function, they are unordered. */
10456 if (DECL_FUNCTION_MEMBER_P (decl1) != DECL_FUNCTION_MEMBER_P (decl2))
10459 /* Don't consider 'this' parameter. */
10460 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10461 args1 = TREE_CHAIN (args1);
10462 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10463 args2 = TREE_CHAIN (args2);
10465 /* If only one is a conversion operator, they are unordered. */
10466 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10469 /* Consider the return type for a conversion function */
10470 if (DECL_CONV_FN_P (decl1))
10472 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10473 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10477 processing_template_decl++;
10481 tree arg1 = TREE_VALUE (args1);
10482 tree arg2 = TREE_VALUE (args2);
10483 int deduce1, deduce2;
10487 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10489 arg1 = TREE_TYPE (arg1);
10490 quals1 = cp_type_quals (arg1);
10493 if (TREE_CODE (arg2) == REFERENCE_TYPE)
10495 arg2 = TREE_TYPE (arg2);
10496 quals2 = cp_type_quals (arg2);
10499 if ((quals1 < 0) != (quals2 < 0))
10501 /* Only of the args is a reference, see if we should apply
10502 array/function pointer decay to it. This is not part of
10503 DR214, but is, IMHO, consistent with the deduction rules
10504 for the function call itself, and with our earlier
10505 implementation of the underspecified partial ordering
10506 rules. (nathan). */
10509 switch (TREE_CODE (arg1))
10512 arg1 = TREE_TYPE (arg1);
10514 case FUNCTION_TYPE:
10515 arg1 = build_pointer_type (arg1);
10524 switch (TREE_CODE (arg2))
10527 arg2 = TREE_TYPE (arg2);
10529 case FUNCTION_TYPE:
10530 arg2 = build_pointer_type (arg2);
10539 arg1 = TYPE_MAIN_VARIANT (arg1);
10540 arg2 = TYPE_MAIN_VARIANT (arg2);
10542 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
10543 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
10549 if (better1 < 0 && better2 < 0)
10550 /* We've failed to deduce something in either direction.
10551 These must be unordered. */
10554 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
10556 /* Deduces in both directions, see if quals can
10557 disambiguate. Pretend the worse one failed to deduce. */
10558 if ((quals1 & quals2) == quals2)
10560 if ((quals1 & quals2) == quals1)
10563 if (deduce1 && !deduce2 && !better2)
10565 if (deduce2 && !deduce1 && !better1)
10568 args1 = TREE_CHAIN (args1);
10569 args2 = TREE_CHAIN (args2);
10572 processing_template_decl--;
10574 return (better1 > 0) - (better2 > 0);
10577 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10579 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10580 -1 if PAT2 is more specialized than PAT1.
10581 0 if neither is more specialized.
10583 FULL_ARGS is the full set of template arguments that triggers this
10584 partial ordering. */
10587 more_specialized_class (tree pat1, tree pat2, tree full_args)
10592 /* Just like what happens for functions, if we are ordering between
10593 different class template specializations, we may encounter dependent
10594 types in the arguments, and we need our dependency check functions
10595 to behave correctly. */
10596 ++processing_template_decl;
10597 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10598 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10602 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10603 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10606 --processing_template_decl;
10611 /* Return the template arguments that will produce the function signature
10612 DECL from the function template FN, with the explicit template
10613 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
10614 also match. Return NULL_TREE if no satisfactory arguments could be
10618 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
10620 int ntparms = DECL_NTPARMS (fn);
10621 tree targs = make_tree_vec (ntparms);
10623 tree decl_arg_types;
10625 /* Substitute the explicit template arguments into the type of DECL.
10626 The call to fn_type_unification will handle substitution into the
10628 decl_type = TREE_TYPE (decl);
10629 if (explicit_args && uses_template_parms (decl_type))
10632 tree converted_args;
10634 if (DECL_TEMPLATE_INFO (decl))
10635 tmpl = DECL_TI_TEMPLATE (decl);
10637 /* We can get here for some invalid specializations. */
10641 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10642 explicit_args, NULL_TREE,
10643 tf_none, /*require_all_arguments=*/0));
10644 if (converted_args == error_mark_node)
10647 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10648 if (decl_type == error_mark_node)
10652 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10653 /* Never do unification on the 'this' parameter. */
10654 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10655 decl_arg_types = TREE_CHAIN (decl_arg_types);
10657 if (fn_type_unification (fn, explicit_args, targs,
10659 (check_rettype || DECL_CONV_FN_P (fn)
10660 ? TREE_TYPE (decl_type) : NULL_TREE),
10667 /* Return the innermost template arguments that, when applied to a
10668 template specialization whose innermost template parameters are
10669 TPARMS, and whose specialization arguments are PARMS, yield the
10672 For example, suppose we have:
10674 template <class T, class U> struct S {};
10675 template <class T> struct S<T*, int> {};
10677 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10678 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10679 int}. The resulting vector will be {double}, indicating that `T'
10680 is bound to `double'. */
10683 get_class_bindings (tree tparms, tree parms, tree args)
10685 int i, ntparms = TREE_VEC_LENGTH (tparms);
10686 tree vec = make_tree_vec (ntparms);
10688 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10692 for (i = 0; i < ntparms; ++i)
10693 if (! TREE_VEC_ELT (vec, i))
10696 if (verify_class_unification (vec, parms, args))
10702 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10703 Pick the most specialized template, and return the corresponding
10704 instantiation, or if there is no corresponding instantiation, the
10705 template itself. If there is no most specialized template,
10706 error_mark_node is returned. If there are no templates at all,
10707 NULL_TREE is returned. */
10710 most_specialized_instantiation (tree instantiations)
10714 if (!instantiations)
10717 ++processing_template_decl;
10719 champ = instantiations;
10720 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10724 if (get_bindings (TREE_VALUE (champ),
10725 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10726 NULL_TREE, /*check_ret=*/false))
10729 if (get_bindings (TREE_VALUE (fn),
10730 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10731 NULL_TREE, /*check_ret=*/false))
10737 /* Equally specialized, move to next function. If there
10738 is no next function, nothing's most specialized. */
10739 fn = TREE_CHAIN (fn);
10745 /* Now verify that champ is better than everything earlier in the
10746 instantiation list. */
10747 for (fn = instantiations; fn != champ; fn = TREE_CHAIN (fn))
10748 if (get_bindings (TREE_VALUE (champ),
10749 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10750 NULL_TREE, /*check_ret=*/false)
10751 || !get_bindings (TREE_VALUE (fn),
10752 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10753 NULL_TREE, /*check_ret=*/false))
10759 processing_template_decl--;
10762 return error_mark_node;
10764 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10767 /* Return the most specialized of the list of templates in FNS that can
10768 produce an instantiation matching DECL, given the explicit template
10769 arguments EXPLICIT_ARGS. */
10772 most_specialized (tree fns, tree decl, tree explicit_args)
10774 tree candidates = NULL_TREE;
10777 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10779 tree candidate = TREE_VALUE (fn);
10781 args = get_bindings (candidate, decl, explicit_args, /*check_ret=*/true);
10783 candidates = tree_cons (NULL_TREE, candidate, candidates);
10786 return most_specialized_instantiation (candidates);
10789 /* If DECL is a specialization of some template, return the most
10790 general such template. Otherwise, returns NULL_TREE.
10792 For example, given:
10794 template <class T> struct S { template <class U> void f(U); };
10796 if TMPL is `template <class U> void S<int>::f(U)' this will return
10797 the full template. This function will not trace past partial
10798 specializations, however. For example, given in addition:
10800 template <class T> struct S<T*> { template <class U> void f(U); };
10802 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10803 `template <class T> template <class U> S<T*>::f(U)'. */
10806 most_general_template (tree decl)
10808 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10809 an immediate specialization. */
10810 if (TREE_CODE (decl) == FUNCTION_DECL)
10812 if (DECL_TEMPLATE_INFO (decl)) {
10813 decl = DECL_TI_TEMPLATE (decl);
10815 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10816 template friend. */
10817 if (TREE_CODE (decl) != TEMPLATE_DECL)
10823 /* Look for more and more general templates. */
10824 while (DECL_TEMPLATE_INFO (decl))
10826 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10827 (See cp-tree.h for details.) */
10828 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10831 if (CLASS_TYPE_P (TREE_TYPE (decl))
10832 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10835 /* Stop if we run into an explicitly specialized class template. */
10836 if (!DECL_NAMESPACE_SCOPE_P (decl)
10837 && DECL_CONTEXT (decl)
10838 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10841 decl = DECL_TI_TEMPLATE (decl);
10847 /* Return the most specialized of the class template specializations
10848 of TMPL which can produce an instantiation matching ARGS, or
10849 error_mark_node if the choice is ambiguous. */
10852 most_specialized_class (tree tmpl, tree args)
10854 tree list = NULL_TREE;
10859 tmpl = most_general_template (tmpl);
10860 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10863 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10866 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10867 TREE_TYPE (list) = TREE_TYPE (t);
10876 t = TREE_CHAIN (t);
10877 for (; t; t = TREE_CHAIN (t))
10879 fate = more_specialized_class (champ, t, args);
10886 t = TREE_CHAIN (t);
10888 return error_mark_node;
10894 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10896 fate = more_specialized_class (champ, t, args);
10898 return error_mark_node;
10904 /* Explicitly instantiate DECL. */
10907 do_decl_instantiation (tree decl, tree storage)
10909 tree result = NULL_TREE;
10913 /* An error occurred, for which grokdeclarator has already issued
10914 an appropriate message. */
10916 else if (! DECL_LANG_SPECIFIC (decl))
10918 error ("explicit instantiation of non-template %q#D", decl);
10921 else if (TREE_CODE (decl) == VAR_DECL)
10923 /* There is an asymmetry here in the way VAR_DECLs and
10924 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10925 the latter, the DECL we get back will be marked as a
10926 template instantiation, and the appropriate
10927 DECL_TEMPLATE_INFO will be set up. This does not happen for
10928 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10929 should handle VAR_DECLs as it currently handles
10931 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10932 if (!result || TREE_CODE (result) != VAR_DECL)
10934 error ("no matching template for %qD found", decl);
10938 else if (TREE_CODE (decl) != FUNCTION_DECL)
10940 error ("explicit instantiation of %q#D", decl);
10946 /* Check for various error cases. Note that if the explicit
10947 instantiation is valid the RESULT will currently be marked as an
10948 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10949 until we get here. */
10951 if (DECL_TEMPLATE_SPECIALIZATION (result))
10953 /* DR 259 [temp.spec].
10955 Both an explicit instantiation and a declaration of an explicit
10956 specialization shall not appear in a program unless the explicit
10957 instantiation follows a declaration of the explicit specialization.
10959 For a given set of template parameters, if an explicit
10960 instantiation of a template appears after a declaration of an
10961 explicit specialization for that template, the explicit
10962 instantiation has no effect. */
10965 else if (DECL_EXPLICIT_INSTANTIATION (result))
10969 No program shall explicitly instantiate any template more
10972 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10973 the first instantiation was `extern' and the second is not,
10974 and EXTERN_P for the opposite case. */
10975 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10976 pedwarn ("duplicate explicit instantiation of %q#D", result);
10977 /* If an "extern" explicit instantiation follows an ordinary
10978 explicit instantiation, the template is instantiated. */
10982 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10984 error ("no matching template for %qD found", result);
10987 else if (!DECL_TEMPLATE_INFO (result))
10989 pedwarn ("explicit instantiation of non-template %q#D", result);
10993 if (storage == NULL_TREE)
10995 else if (storage == ridpointers[(int) RID_EXTERN])
10997 if (pedantic && !in_system_header)
10998 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11003 error ("storage class %qD applied to template instantiation", storage);
11005 mark_decl_instantiated (result, extern_p);
11007 instantiate_decl (result, /*defer_ok=*/1, /*undefined_ok=*/0);
11011 mark_class_instantiated (tree t, int extern_p)
11013 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11014 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11015 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11016 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11019 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11020 rest_of_type_compilation (t, 1);
11024 /* Called from do_type_instantiation through binding_table_foreach to
11025 do recursive instantiation for the type bound in ENTRY. */
11027 bt_instantiate_type_proc (binding_entry entry, void *data)
11029 tree storage = *(tree *) data;
11031 if (IS_AGGR_TYPE (entry->type)
11032 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11033 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11036 /* Called from do_type_instantiation to instantiate a member
11037 (a member function or a static member variable) of an
11038 explicitly instantiated class template. */
11040 instantiate_class_member (tree decl, int extern_p)
11042 mark_decl_instantiated (decl, extern_p);
11044 instantiate_decl (decl, /*defer_ok=*/1, /* undefined_ok=*/1);
11047 /* Perform an explicit instantiation of template class T. STORAGE, if
11048 non-null, is the RID for extern, inline or static. COMPLAIN is
11049 nonzero if this is called from the parser, zero if called recursively,
11050 since the standard is unclear (as detailed below). */
11053 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11058 int previous_instantiation_extern_p = 0;
11060 if (TREE_CODE (t) == TYPE_DECL)
11063 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11065 error ("explicit instantiation of non-template type %qT", t);
11071 if (!COMPLETE_TYPE_P (t))
11073 if (complain & tf_error)
11074 error ("explicit instantiation of %q#T before definition of template",
11079 if (storage != NULL_TREE)
11081 if (pedantic && !in_system_header)
11082 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11085 if (storage == ridpointers[(int) RID_INLINE])
11087 else if (storage == ridpointers[(int) RID_EXTERN])
11089 else if (storage == ridpointers[(int) RID_STATIC])
11093 error ("storage class %qD applied to template instantiation",
11099 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11101 /* DR 259 [temp.spec].
11103 Both an explicit instantiation and a declaration of an explicit
11104 specialization shall not appear in a program unless the explicit
11105 instantiation follows a declaration of the explicit specialization.
11107 For a given set of template parameters, if an explicit
11108 instantiation of a template appears after a declaration of an
11109 explicit specialization for that template, the explicit
11110 instantiation has no effect. */
11113 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11117 No program shall explicitly instantiate any template more
11120 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11121 instantiation was `extern'. If EXTERN_P then the second is.
11122 These cases are OK. */
11123 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11125 if (!previous_instantiation_extern_p && !extern_p
11126 && (complain & tf_error))
11127 pedwarn ("duplicate explicit instantiation of %q#T", t);
11129 /* If we've already instantiated the template, just return now. */
11130 if (!CLASSTYPE_INTERFACE_ONLY (t))
11134 mark_class_instantiated (t, extern_p);
11142 /* In contrast to implicit instantiation, where only the
11143 declarations, and not the definitions, of members are
11144 instantiated, we have here:
11148 The explicit instantiation of a class template specialization
11149 implies the instantiation of all of its members not
11150 previously explicitly specialized in the translation unit
11151 containing the explicit instantiation.
11153 Of course, we can't instantiate member template classes, since
11154 we don't have any arguments for them. Note that the standard
11155 is unclear on whether the instantiation of the members are
11156 *explicit* instantiations or not. However, the most natural
11157 interpretation is that it should be an explicit instantiation. */
11160 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11161 if (TREE_CODE (tmp) == FUNCTION_DECL
11162 && DECL_TEMPLATE_INSTANTIATION (tmp))
11163 instantiate_class_member (tmp, extern_p);
11165 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11166 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11167 instantiate_class_member (tmp, extern_p);
11169 if (CLASSTYPE_NESTED_UTDS (t))
11170 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11171 bt_instantiate_type_proc, &storage);
11175 /* Given a function DECL, which is a specialization of TMPL, modify
11176 DECL to be a re-instantiation of TMPL with the same template
11177 arguments. TMPL should be the template into which tsubst'ing
11178 should occur for DECL, not the most general template.
11180 One reason for doing this is a scenario like this:
11183 void f(const T&, int i);
11185 void g() { f(3, 7); }
11188 void f(const T& t, const int i) { }
11190 Note that when the template is first instantiated, with
11191 instantiate_template, the resulting DECL will have no name for the
11192 first parameter, and the wrong type for the second. So, when we go
11193 to instantiate the DECL, we regenerate it. */
11196 regenerate_decl_from_template (tree decl, tree tmpl)
11198 /* The arguments used to instantiate DECL, from the most general
11203 args = DECL_TI_ARGS (decl);
11204 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11206 /* Make sure that we can see identifiers, and compute access
11208 push_access_scope (decl);
11210 if (TREE_CODE (decl) == FUNCTION_DECL)
11218 args_depth = TMPL_ARGS_DEPTH (args);
11219 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11220 if (args_depth > parms_depth)
11221 args = get_innermost_template_args (args, parms_depth);
11223 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11224 args, tf_error, NULL_TREE);
11226 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11229 /* Merge parameter declarations. */
11230 decl_parm = skip_artificial_parms_for (decl,
11231 DECL_ARGUMENTS (decl));
11233 = skip_artificial_parms_for (code_pattern,
11234 DECL_ARGUMENTS (code_pattern));
11240 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11241 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11242 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11244 parm_type = type_decays_to (parm_type);
11245 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11246 TREE_TYPE (decl_parm) = parm_type;
11247 attributes = DECL_ATTRIBUTES (pattern_parm);
11248 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11250 DECL_ATTRIBUTES (decl_parm) = attributes;
11251 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11253 decl_parm = TREE_CHAIN (decl_parm);
11254 pattern_parm = TREE_CHAIN (pattern_parm);
11257 /* Merge additional specifiers from the CODE_PATTERN. */
11258 if (DECL_DECLARED_INLINE_P (code_pattern)
11259 && !DECL_DECLARED_INLINE_P (decl))
11260 DECL_DECLARED_INLINE_P (decl) = 1;
11261 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11262 DECL_INLINE (decl) = 1;
11264 else if (TREE_CODE (decl) == VAR_DECL)
11266 if (!DECL_INITIALIZED_IN_CLASS_P (decl)
11267 && DECL_INITIAL (code_pattern))
11268 DECL_INITIAL (decl) =
11269 tsubst_expr (DECL_INITIAL (code_pattern), args,
11270 tf_error, DECL_TI_TEMPLATE (decl));
11273 gcc_unreachable ();
11275 pop_access_scope (decl);
11278 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11279 substituted to get DECL. */
11282 template_for_substitution (tree decl)
11284 tree tmpl = DECL_TI_TEMPLATE (decl);
11286 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11287 for the instantiation. This is not always the most general
11288 template. Consider, for example:
11291 struct S { template <class U> void f();
11292 template <> void f<int>(); };
11294 and an instantiation of S<double>::f<int>. We want TD to be the
11295 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11296 while (/* An instantiation cannot have a definition, so we need a
11297 more general template. */
11298 DECL_TEMPLATE_INSTANTIATION (tmpl)
11299 /* We must also deal with friend templates. Given:
11301 template <class T> struct S {
11302 template <class U> friend void f() {};
11305 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11306 so far as the language is concerned, but that's still
11307 where we get the pattern for the instantiation from. On
11308 other hand, if the definition comes outside the class, say:
11310 template <class T> struct S {
11311 template <class U> friend void f();
11313 template <class U> friend void f() {}
11315 we don't need to look any further. That's what the check for
11316 DECL_INITIAL is for. */
11317 || (TREE_CODE (decl) == FUNCTION_DECL
11318 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11319 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11321 /* The present template, TD, should not be a definition. If it
11322 were a definition, we should be using it! Note that we
11323 cannot restructure the loop to just keep going until we find
11324 a template with a definition, since that might go too far if
11325 a specialization was declared, but not defined. */
11326 gcc_assert (TREE_CODE (decl) != VAR_DECL
11327 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11329 /* Fetch the more general template. */
11330 tmpl = DECL_TI_TEMPLATE (tmpl);
11336 /* Produce the definition of D, a _DECL generated from a template. If
11337 DEFER_OK is nonzero, then we don't have to actually do the
11338 instantiation now; we just have to do it sometime. Normally it is
11339 an error if this is an explicit instantiation but D is undefined.
11340 If UNDEFINED_OK is nonzero, then instead we treat it as an implicit
11341 instantiation. UNDEFINED_OK is nonzero only if we are being used
11342 to instantiate the members of an explicitly instantiated class
11347 instantiate_decl (tree d, int defer_ok, int undefined_ok)
11349 tree tmpl = DECL_TI_TEMPLATE (d);
11356 int pattern_defined;
11358 location_t saved_loc = input_location;
11360 /* This function should only be used to instantiate templates for
11361 functions and static member variables. */
11362 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11363 || TREE_CODE (d) == VAR_DECL);
11365 /* Variables are never deferred; if instantiation is required, they
11366 are instantiated right away. That allows for better code in the
11367 case that an expression refers to the value of the variable --
11368 if the variable has a constant value the referring expression can
11369 take advantage of that fact. */
11370 if (TREE_CODE (d) == VAR_DECL)
11373 /* Don't instantiate cloned functions. Instead, instantiate the
11374 functions they cloned. */
11375 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11376 d = DECL_CLONED_FUNCTION (d);
11378 if (DECL_TEMPLATE_INSTANTIATED (d))
11379 /* D has already been instantiated. It might seem reasonable to
11380 check whether or not D is an explicit instantiation, and, if so,
11381 stop here. But when an explicit instantiation is deferred
11382 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11383 is set, even though we still need to do the instantiation. */
11386 /* If we already have a specialization of this declaration, then
11387 there's no reason to instantiate it. Note that
11388 retrieve_specialization gives us both instantiations and
11389 specializations, so we must explicitly check
11390 DECL_TEMPLATE_SPECIALIZATION. */
11391 gen_tmpl = most_general_template (tmpl);
11392 gen_args = DECL_TI_ARGS (d);
11393 spec = retrieve_specialization (gen_tmpl, gen_args,
11394 /*class_specializations_p=*/false);
11395 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11398 /* This needs to happen before any tsubsting. */
11399 if (! push_tinst_level (d))
11402 timevar_push (TV_PARSE);
11404 /* We may be in the middle of deferred access check. Disable it now. */
11405 push_deferring_access_checks (dk_no_deferred);
11407 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11408 for the instantiation. */
11409 td = template_for_substitution (d);
11410 code_pattern = DECL_TEMPLATE_RESULT (td);
11412 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11413 || DECL_TEMPLATE_SPECIALIZATION (td))
11414 /* In the case of a friend template whose definition is provided
11415 outside the class, we may have too many arguments. Drop the
11416 ones we don't need. The same is true for specializations. */
11417 args = get_innermost_template_args
11418 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11422 if (TREE_CODE (d) == FUNCTION_DECL)
11423 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11425 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11426 /* Unless an explicit instantiation directive has already determined
11427 the linkage of D, remember that a definition is available for
11429 if (pattern_defined
11430 && !DECL_INTERFACE_KNOWN (d)
11431 && !DECL_NOT_REALLY_EXTERN (d))
11432 mark_definable (d);
11434 input_location = DECL_SOURCE_LOCATION (d);
11436 if (! pattern_defined && DECL_EXPLICIT_INSTANTIATION (d) && undefined_ok)
11438 DECL_NOT_REALLY_EXTERN (d) = 0;
11439 SET_DECL_IMPLICIT_INSTANTIATION (d);
11444 /* Recheck the substitutions to obtain any warning messages
11445 about ignoring cv qualifiers. */
11446 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11447 tree type = TREE_TYPE (gen);
11449 /* Make sure that we can see identifiers, and compute access
11450 correctly. D is already the target FUNCTION_DECL with the
11452 push_access_scope (d);
11454 if (TREE_CODE (gen) == FUNCTION_DECL)
11456 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11457 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11458 tf_error | tf_warning, d);
11459 /* Don't simply tsubst the function type, as that will give
11460 duplicate warnings about poor parameter qualifications.
11461 The function arguments are the same as the decl_arguments
11462 without the top level cv qualifiers. */
11463 type = TREE_TYPE (type);
11465 tsubst (type, gen_args, tf_error | tf_warning, d);
11467 pop_access_scope (d);
11470 /* We should have set up DECL_INITIAL in instantiate_class_template
11471 for in-class definitions of static data members. */
11472 gcc_assert (!(TREE_CODE (d) == VAR_DECL
11473 && DECL_INITIALIZED_IN_CLASS_P (d)
11474 && DECL_INITIAL (d) == NULL_TREE));
11476 /* Do not instantiate templates that we know will be defined
11478 if (DECL_INTERFACE_KNOWN (d)
11479 && DECL_REALLY_EXTERN (d)
11480 && ! (TREE_CODE (d) == FUNCTION_DECL
11481 && DECL_INLINE (d)))
11483 /* Defer all other templates, unless we have been explicitly
11484 forbidden from doing so. We restore the source position here
11485 because it's used by add_pending_template. */
11486 else if (! pattern_defined || defer_ok)
11488 input_location = saved_loc;
11490 if (at_eof && !pattern_defined
11491 && DECL_EXPLICIT_INSTANTIATION (d))
11494 The definition of a non-exported function template, a
11495 non-exported member function template, or a non-exported
11496 member function or static data member of a class template
11497 shall be present in every translation unit in which it is
11498 explicitly instantiated. */
11500 ("explicit instantiation of %qD but no definition available", d);
11502 add_pending_template (d);
11505 /* Tell the repository that D is available in this translation unit
11506 -- and see if it is supposed to be instantiated here. */
11507 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11509 /* In a PCH file, despite the fact that the repository hasn't
11510 requested instantiation in the PCH it is still possible that
11511 an instantiation will be required in a file that includes the
11514 add_pending_template (d);
11515 /* Instantiate inline functions so that the inliner can do its
11516 job, even though we'll not be emitting a copy of this
11518 if (!(TREE_CODE (d) == FUNCTION_DECL
11519 && flag_inline_trees
11520 && DECL_DECLARED_INLINE_P (d)))
11524 need_push = !cfun || !global_bindings_p ();
11526 push_to_top_level ();
11528 /* Mark D as instantiated so that recursive calls to
11529 instantiate_decl do not try to instantiate it again. */
11530 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11532 /* Regenerate the declaration in case the template has been modified
11533 by a subsequent redeclaration. */
11534 regenerate_decl_from_template (d, td);
11536 /* We already set the file and line above. Reset them now in case
11537 they changed as a result of calling regenerate_decl_from_template. */
11538 input_location = DECL_SOURCE_LOCATION (d);
11540 if (TREE_CODE (d) == VAR_DECL)
11542 /* Clear out DECL_RTL; whatever was there before may not be right
11543 since we've reset the type of the declaration. */
11544 SET_DECL_RTL (d, NULL_RTX);
11545 DECL_IN_AGGR_P (d) = 0;
11547 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11548 initializer. That function will defer actual emission until
11549 we have a chance to determine linkage. */
11550 DECL_EXTERNAL (d) = 0;
11552 /* Enter the scope of D so that access-checking works correctly. */
11553 push_nested_class (DECL_CONTEXT (d));
11555 (!DECL_INITIALIZED_IN_CLASS_P (d)
11556 ? DECL_INITIAL (d) : NULL_TREE),
11558 pop_nested_class ();
11560 else if (TREE_CODE (d) == FUNCTION_DECL)
11562 htab_t saved_local_specializations;
11567 /* Save away the current list, in case we are instantiating one
11568 template from within the body of another. */
11569 saved_local_specializations = local_specializations;
11571 /* Set up the list of local specializations. */
11572 local_specializations = htab_create (37,
11573 hash_local_specialization,
11574 eq_local_specializations,
11577 /* Set up context. */
11578 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11580 /* Create substitution entries for the parameters. */
11581 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11582 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11583 spec_parm = DECL_ARGUMENTS (d);
11584 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11586 register_local_specialization (spec_parm, tmpl_parm);
11587 spec_parm = skip_artificial_parms_for (d, spec_parm);
11588 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11592 register_local_specialization (spec_parm, tmpl_parm);
11593 tmpl_parm = TREE_CHAIN (tmpl_parm);
11594 spec_parm = TREE_CHAIN (spec_parm);
11596 gcc_assert (!spec_parm);
11598 /* Substitute into the body of the function. */
11599 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11600 tf_error | tf_warning, tmpl);
11602 /* We don't need the local specializations any more. */
11603 htab_delete (local_specializations);
11604 local_specializations = saved_local_specializations;
11606 /* Finish the function. */
11607 d = finish_function (0);
11608 expand_or_defer_fn (d);
11611 /* We're not deferring instantiation any more. */
11612 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11615 pop_from_top_level ();
11618 input_location = saved_loc;
11619 pop_deferring_access_checks ();
11620 pop_tinst_level ();
11622 timevar_pop (TV_PARSE);
11627 /* Run through the list of templates that we wish we could
11628 instantiate, and instantiate any we can. RETRIES is the
11629 number of times we retry pending template instantiation. */
11632 instantiate_pending_templates (int retries)
11635 tree last = NULL_TREE;
11637 location_t saved_loc = input_location;
11638 int saved_in_system_header = in_system_header;
11640 /* Instantiating templates may trigger vtable generation. This in turn
11641 may require further template instantiations. We place a limit here
11642 to avoid infinite loop. */
11643 if (pending_templates && retries >= max_tinst_depth)
11645 error ("template instantiation depth exceeds maximum of %d"
11646 " instantiating %q+D, possibly from virtual table generation"
11647 " (use -ftemplate-depth-NN to increase the maximum)",
11648 max_tinst_depth, TREE_VALUE (pending_templates));
11656 t = &pending_templates;
11659 tree instantiation = TREE_VALUE (*t);
11661 reopen_tinst_level (TREE_PURPOSE (*t));
11663 if (TYPE_P (instantiation))
11667 if (!COMPLETE_TYPE_P (instantiation))
11669 instantiate_class_template (instantiation);
11670 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11671 for (fn = TYPE_METHODS (instantiation);
11673 fn = TREE_CHAIN (fn))
11674 if (! DECL_ARTIFICIAL (fn))
11675 instantiate_decl (fn, /*defer_ok=*/0,
11676 /*undefined_ok=*/0);
11677 if (COMPLETE_TYPE_P (instantiation))
11681 if (COMPLETE_TYPE_P (instantiation))
11682 /* If INSTANTIATION has been instantiated, then we don't
11683 need to consider it again in the future. */
11684 *t = TREE_CHAIN (*t);
11688 t = &TREE_CHAIN (*t);
11693 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11694 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11696 instantiation = instantiate_decl (instantiation,
11698 /*undefined_ok=*/0);
11699 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11703 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11704 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11705 /* If INSTANTIATION has been instantiated, then we don't
11706 need to consider it again in the future. */
11707 *t = TREE_CHAIN (*t);
11711 t = &TREE_CHAIN (*t);
11715 current_tinst_level = NULL_TREE;
11717 last_pending_template = last;
11719 while (reconsider);
11721 input_location = saved_loc;
11722 in_system_header = saved_in_system_header;
11725 /* Substitute ARGVEC into T, which is a list of initializers for
11726 either base class or a non-static data member. The TREE_PURPOSEs
11727 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11728 instantiate_decl. */
11731 tsubst_initializer_list (tree t, tree argvec)
11733 tree inits = NULL_TREE;
11735 for (; t; t = TREE_CHAIN (t))
11740 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11742 decl = expand_member_init (decl);
11743 if (decl && !DECL_P (decl))
11744 in_base_initializer = 1;
11746 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11748 in_base_initializer = 0;
11752 init = build_tree_list (decl, init);
11753 TREE_CHAIN (init) = inits;
11760 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11763 set_current_access_from_decl (tree decl)
11765 if (TREE_PRIVATE (decl))
11766 current_access_specifier = access_private_node;
11767 else if (TREE_PROTECTED (decl))
11768 current_access_specifier = access_protected_node;
11770 current_access_specifier = access_public_node;
11773 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11774 is the instantiation (which should have been created with
11775 start_enum) and ARGS are the template arguments to use. */
11778 tsubst_enum (tree tag, tree newtag, tree args)
11782 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11787 decl = TREE_VALUE (e);
11788 /* Note that in a template enum, the TREE_VALUE is the
11789 CONST_DECL, not the corresponding INTEGER_CST. */
11790 value = tsubst_expr (DECL_INITIAL (decl),
11791 args, tf_error | tf_warning,
11794 /* Give this enumeration constant the correct access. */
11795 set_current_access_from_decl (decl);
11797 /* Actually build the enumerator itself. */
11798 build_enumerator (DECL_NAME (decl), value, newtag);
11801 finish_enum (newtag);
11802 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11803 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11806 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11807 its type -- but without substituting the innermost set of template
11808 arguments. So, innermost set of template parameters will appear in
11812 get_mostly_instantiated_function_type (tree decl)
11820 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11821 targs = DECL_TI_ARGS (decl);
11822 tparms = DECL_TEMPLATE_PARMS (tmpl);
11823 parm_depth = TMPL_PARMS_DEPTH (tparms);
11825 /* There should be as many levels of arguments as there are levels
11827 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11829 fn_type = TREE_TYPE (tmpl);
11831 if (parm_depth == 1)
11832 /* No substitution is necessary. */
11836 int i, save_access_control;
11839 /* Replace the innermost level of the TARGS with NULL_TREEs to
11840 let tsubst know not to substitute for those parameters. */
11841 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11842 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11843 SET_TMPL_ARGS_LEVEL (partial_args, i,
11844 TMPL_ARGS_LEVEL (targs, i));
11845 SET_TMPL_ARGS_LEVEL (partial_args,
11846 TMPL_ARGS_DEPTH (targs),
11847 make_tree_vec (DECL_NTPARMS (tmpl)));
11849 /* Disable access control as this function is used only during
11851 save_access_control = flag_access_control;
11852 flag_access_control = 0;
11854 ++processing_template_decl;
11855 /* Now, do the (partial) substitution to figure out the
11856 appropriate function type. */
11857 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11858 --processing_template_decl;
11860 /* Substitute into the template parameters to obtain the real
11861 innermost set of parameters. This step is important if the
11862 innermost set of template parameters contains value
11863 parameters whose types depend on outer template parameters. */
11864 TREE_VEC_LENGTH (partial_args)--;
11865 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11867 flag_access_control = save_access_control;
11873 /* Return truthvalue if we're processing a template different from
11874 the last one involved in diagnostics. */
11876 problematic_instantiation_changed (void)
11878 return last_template_error_tick != tinst_level_tick;
11881 /* Remember current template involved in diagnostics. */
11883 record_last_problematic_instantiation (void)
11885 last_template_error_tick = tinst_level_tick;
11889 current_instantiation (void)
11891 return current_tinst_level;
11894 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11895 type. Return zero for ok, nonzero for disallowed. Issue error and
11896 warning messages under control of COMPLAIN. */
11899 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11901 if (INTEGRAL_TYPE_P (type))
11903 else if (POINTER_TYPE_P (type))
11905 else if (TYPE_PTR_TO_MEMBER_P (type))
11907 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11909 else if (TREE_CODE (type) == TYPENAME_TYPE)
11912 if (complain & tf_error)
11913 error ("%q#T is not a valid type for a template constant parameter", type);
11917 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11918 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11921 dependent_type_p_r (tree type)
11927 A type is dependent if it is:
11929 -- a template parameter. Template template parameters are types
11930 for us (since TYPE_P holds true for them) so we handle
11932 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11933 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11935 /* -- a qualified-id with a nested-name-specifier which contains a
11936 class-name that names a dependent type or whose unqualified-id
11937 names a dependent type. */
11938 if (TREE_CODE (type) == TYPENAME_TYPE)
11940 /* -- a cv-qualified type where the cv-unqualified type is
11942 type = TYPE_MAIN_VARIANT (type);
11943 /* -- a compound type constructed from any dependent type. */
11944 if (TYPE_PTR_TO_MEMBER_P (type))
11945 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11946 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11948 else if (TREE_CODE (type) == POINTER_TYPE
11949 || TREE_CODE (type) == REFERENCE_TYPE)
11950 return dependent_type_p (TREE_TYPE (type));
11951 else if (TREE_CODE (type) == FUNCTION_TYPE
11952 || TREE_CODE (type) == METHOD_TYPE)
11956 if (dependent_type_p (TREE_TYPE (type)))
11958 for (arg_type = TYPE_ARG_TYPES (type);
11960 arg_type = TREE_CHAIN (arg_type))
11961 if (dependent_type_p (TREE_VALUE (arg_type)))
11965 /* -- an array type constructed from any dependent type or whose
11966 size is specified by a constant expression that is
11967 value-dependent. */
11968 if (TREE_CODE (type) == ARRAY_TYPE)
11970 if (TYPE_DOMAIN (type)
11971 && ((value_dependent_expression_p
11972 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11973 || (type_dependent_expression_p
11974 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11976 return dependent_type_p (TREE_TYPE (type));
11979 /* -- a template-id in which either the template name is a template
11981 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11983 /* ... or any of the template arguments is a dependent type or
11984 an expression that is type-dependent or value-dependent. */
11985 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11986 && (any_dependent_template_arguments_p
11987 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11990 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11991 expression is not type-dependent, then it should already been
11993 if (TREE_CODE (type) == TYPEOF_TYPE)
11996 /* The standard does not specifically mention types that are local
11997 to template functions or local classes, but they should be
11998 considered dependent too. For example:
12000 template <int I> void f() {
12005 The size of `E' cannot be known until the value of `I' has been
12006 determined. Therefore, `E' must be considered dependent. */
12007 scope = TYPE_CONTEXT (type);
12008 if (scope && TYPE_P (scope))
12009 return dependent_type_p (scope);
12010 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12011 return type_dependent_expression_p (scope);
12013 /* Other types are non-dependent. */
12017 /* Returns TRUE if TYPE is dependent, in the sense of
12018 [temp.dep.type]. */
12021 dependent_type_p (tree type)
12023 /* If there are no template parameters in scope, then there can't be
12024 any dependent types. */
12025 if (!processing_template_decl)
12028 /* If the type is NULL, we have not computed a type for the entity
12029 in question; in that case, the type is dependent. */
12033 /* Erroneous types can be considered non-dependent. */
12034 if (type == error_mark_node)
12037 /* If we have not already computed the appropriate value for TYPE,
12039 if (!TYPE_DEPENDENT_P_VALID (type))
12041 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12042 TYPE_DEPENDENT_P_VALID (type) = 1;
12045 return TYPE_DEPENDENT_P (type);
12048 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12051 dependent_scope_ref_p (tree expression, bool criterion (tree))
12056 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12058 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12061 scope = TREE_OPERAND (expression, 0);
12062 name = TREE_OPERAND (expression, 1);
12066 An id-expression is type-dependent if it contains a
12067 nested-name-specifier that contains a class-name that names a
12069 /* The suggested resolution to Core Issue 2 implies that if the
12070 qualifying type is the current class, then we must peek
12073 && currently_open_class (scope)
12074 && !criterion (name))
12076 if (dependent_type_p (scope))
12082 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12083 [temp.dep.constexpr] */
12086 value_dependent_expression_p (tree expression)
12088 if (!processing_template_decl)
12091 /* A name declared with a dependent type. */
12092 if (DECL_P (expression) && type_dependent_expression_p (expression))
12095 switch (TREE_CODE (expression))
12097 case IDENTIFIER_NODE:
12098 /* A name that has not been looked up -- must be dependent. */
12101 case TEMPLATE_PARM_INDEX:
12102 /* A non-type template parm. */
12106 /* A non-type template parm. */
12107 if (DECL_TEMPLATE_PARM_P (expression))
12112 /* A constant with integral or enumeration type and is initialized
12113 with an expression that is value-dependent. */
12114 if (DECL_INITIAL (expression)
12115 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12116 && value_dependent_expression_p (DECL_INITIAL (expression)))
12120 case DYNAMIC_CAST_EXPR:
12121 case STATIC_CAST_EXPR:
12122 case CONST_CAST_EXPR:
12123 case REINTERPRET_CAST_EXPR:
12125 /* These expressions are value-dependent if the type to which
12126 the cast occurs is dependent or the expression being casted
12127 is value-dependent. */
12129 tree type = TREE_TYPE (expression);
12131 if (dependent_type_p (type))
12134 /* A functional cast has a list of operands. */
12135 expression = TREE_OPERAND (expression, 0);
12138 /* If there are no operands, it must be an expression such
12139 as "int()". This should not happen for aggregate types
12140 because it would form non-constant expressions. */
12141 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12146 if (TREE_CODE (expression) == TREE_LIST)
12148 for (; expression; expression = TREE_CHAIN (expression))
12149 if (value_dependent_expression_p (TREE_VALUE (expression)))
12154 return value_dependent_expression_p (expression);
12159 /* A `sizeof' expression is value-dependent if the operand is
12161 expression = TREE_OPERAND (expression, 0);
12162 if (TYPE_P (expression))
12163 return dependent_type_p (expression);
12164 return type_dependent_expression_p (expression);
12167 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12169 case COMPONENT_REF:
12170 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12171 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12174 /* A CALL_EXPR is value-dependent if any argument is
12175 value-dependent. Why do we have to handle CALL_EXPRs in this
12176 function at all? First, some function calls, those for which
12177 value_dependent_expression_p is true, man appear in constant
12178 expressions. Second, there appear to be bugs which result in
12179 other CALL_EXPRs reaching this point. */
12181 tree function = TREE_OPERAND (expression, 0);
12182 tree args = TREE_OPERAND (expression, 1);
12184 if (value_dependent_expression_p (function))
12190 if (TREE_CODE (args) == TREE_LIST)
12192 for (; args; args = TREE_CHAIN (args))
12193 if (value_dependent_expression_p (TREE_VALUE (args)))
12198 return value_dependent_expression_p (args);
12202 /* A constant expression is value-dependent if any subexpression is
12203 value-dependent. */
12204 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12206 case tcc_reference:
12208 return (value_dependent_expression_p
12209 (TREE_OPERAND (expression, 0)));
12211 case tcc_comparison:
12213 return ((value_dependent_expression_p
12214 (TREE_OPERAND (expression, 0)))
12215 || (value_dependent_expression_p
12216 (TREE_OPERAND (expression, 1))));
12218 case tcc_expression:
12221 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12222 /* In some cases, some of the operands may be missing.
12223 (For example, in the case of PREDECREMENT_EXPR, the
12224 amount to increment by may be missing.) That doesn't
12225 make the expression dependent. */
12226 if (TREE_OPERAND (expression, i)
12227 && (value_dependent_expression_p
12228 (TREE_OPERAND (expression, i))))
12238 /* The expression is not value-dependent. */
12242 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12243 [temp.dep.expr]. */
12246 type_dependent_expression_p (tree expression)
12248 if (!processing_template_decl)
12251 if (expression == error_mark_node)
12254 /* An unresolved name is always dependent. */
12255 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12258 /* Some expression forms are never type-dependent. */
12259 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12260 || TREE_CODE (expression) == SIZEOF_EXPR
12261 || TREE_CODE (expression) == ALIGNOF_EXPR
12262 || TREE_CODE (expression) == TYPEID_EXPR
12263 || TREE_CODE (expression) == DELETE_EXPR
12264 || TREE_CODE (expression) == VEC_DELETE_EXPR
12265 || TREE_CODE (expression) == THROW_EXPR)
12268 /* The types of these expressions depends only on the type to which
12269 the cast occurs. */
12270 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12271 || TREE_CODE (expression) == STATIC_CAST_EXPR
12272 || TREE_CODE (expression) == CONST_CAST_EXPR
12273 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12274 || TREE_CODE (expression) == CAST_EXPR)
12275 return dependent_type_p (TREE_TYPE (expression));
12277 /* The types of these expressions depends only on the type created
12278 by the expression. */
12279 if (TREE_CODE (expression) == NEW_EXPR
12280 || TREE_CODE (expression) == VEC_NEW_EXPR)
12282 /* For NEW_EXPR tree nodes created inside a template, either
12283 the object type itself or a TREE_LIST may appear as the
12285 tree type = TREE_OPERAND (expression, 1);
12286 if (TREE_CODE (type) == TREE_LIST)
12287 /* This is an array type. We need to check array dimensions
12289 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12290 || value_dependent_expression_p
12291 (TREE_OPERAND (TREE_VALUE (type), 1));
12293 return dependent_type_p (type);
12296 if (TREE_CODE (expression) == SCOPE_REF
12297 && dependent_scope_ref_p (expression,
12298 type_dependent_expression_p))
12301 if (TREE_CODE (expression) == FUNCTION_DECL
12302 && DECL_LANG_SPECIFIC (expression)
12303 && DECL_TEMPLATE_INFO (expression)
12304 && (any_dependent_template_arguments_p
12305 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12308 if (TREE_CODE (expression) == TEMPLATE_DECL
12309 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12312 if (TREE_TYPE (expression) == unknown_type_node)
12314 if (TREE_CODE (expression) == ADDR_EXPR)
12315 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12316 if (TREE_CODE (expression) == COMPONENT_REF
12317 || TREE_CODE (expression) == OFFSET_REF)
12319 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12321 expression = TREE_OPERAND (expression, 1);
12322 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12325 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12326 if (TREE_CODE (expression) == SCOPE_REF)
12329 if (TREE_CODE (expression) == BASELINK)
12330 expression = BASELINK_FUNCTIONS (expression);
12332 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12334 if (any_dependent_template_arguments_p
12335 (TREE_OPERAND (expression, 1)))
12337 expression = TREE_OPERAND (expression, 0);
12339 gcc_assert (TREE_CODE (expression) == OVERLOAD);
12343 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12345 expression = OVL_NEXT (expression);
12350 return (dependent_type_p (TREE_TYPE (expression)));
12353 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12354 contains a type-dependent expression. */
12357 any_type_dependent_arguments_p (tree args)
12361 tree arg = TREE_VALUE (args);
12363 if (type_dependent_expression_p (arg))
12365 args = TREE_CHAIN (args);
12370 /* Returns TRUE if the ARG (a template argument) is dependent. */
12373 dependent_template_arg_p (tree arg)
12375 if (!processing_template_decl)
12378 if (TREE_CODE (arg) == TEMPLATE_DECL
12379 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12380 return dependent_template_p (arg);
12381 else if (TYPE_P (arg))
12382 return dependent_type_p (arg);
12384 return (type_dependent_expression_p (arg)
12385 || value_dependent_expression_p (arg));
12388 /* Returns true if ARGS (a collection of template arguments) contains
12389 any dependent arguments. */
12392 any_dependent_template_arguments_p (tree args)
12400 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12402 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12403 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12404 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12411 /* Returns TRUE if the template TMPL is dependent. */
12414 dependent_template_p (tree tmpl)
12416 if (TREE_CODE (tmpl) == OVERLOAD)
12420 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12422 tmpl = OVL_CHAIN (tmpl);
12427 /* Template template parameters are dependent. */
12428 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12429 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12431 /* So are names that have not been looked up. */
12432 if (TREE_CODE (tmpl) == SCOPE_REF
12433 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12435 /* So are member templates of dependent classes. */
12436 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12437 return dependent_type_p (DECL_CONTEXT (tmpl));
12441 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12444 dependent_template_id_p (tree tmpl, tree args)
12446 return (dependent_template_p (tmpl)
12447 || any_dependent_template_arguments_p (args));
12450 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12451 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12452 can be found. Note that this function peers inside uninstantiated
12453 templates and therefore should be used only in extremely limited
12454 situations. ONLY_CURRENT_P restricts this peering to the currently
12455 open classes hierarchy (which is required when comparing types). */
12458 resolve_typename_type (tree type, bool only_current_p)
12466 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12468 scope = TYPE_CONTEXT (type);
12469 name = TYPE_IDENTIFIER (type);
12471 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12472 it first before we can figure out what NAME refers to. */
12473 if (TREE_CODE (scope) == TYPENAME_TYPE)
12474 scope = resolve_typename_type (scope, only_current_p);
12475 /* If we don't know what SCOPE refers to, then we cannot resolve the
12477 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12478 return error_mark_node;
12479 /* If the SCOPE is a template type parameter, we have no way of
12480 resolving the name. */
12481 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12483 /* If the SCOPE is not the current instantiation, there's no reason
12484 to look inside it. */
12485 if (only_current_p && !currently_open_class (scope))
12486 return error_mark_node;
12487 /* If SCOPE is a partial instantiation, it will not have a valid
12488 TYPE_FIELDS list, so use the original template. */
12489 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12490 /* Enter the SCOPE so that name lookup will be resolved as if we
12491 were in the class definition. In particular, SCOPE will no
12492 longer be considered a dependent type. */
12493 pushed_scope = push_scope (scope);
12494 /* Look up the declaration. */
12495 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12496 /* Obtain the set of qualifiers applied to the TYPE. */
12497 quals = cp_type_quals (type);
12498 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12499 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12501 type = error_mark_node;
12502 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12503 && TREE_CODE (decl) == TYPE_DECL)
12504 type = TREE_TYPE (decl);
12505 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12506 && DECL_CLASS_TEMPLATE_P (decl))
12510 /* Obtain the template and the arguments. */
12511 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12512 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12513 /* Instantiate the template. */
12514 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12515 /*entering_scope=*/0, tf_error | tf_user);
12518 type = error_mark_node;
12519 /* Qualify the resulting type. */
12520 if (type != error_mark_node && quals)
12521 type = cp_build_qualified_type (type, quals);
12522 /* Leave the SCOPE. */
12524 pop_scope (pushed_scope);
12529 /* EXPR is an expression which is not type-dependent. Return a proxy
12530 for EXPR that can be used to compute the types of larger
12531 expressions containing EXPR. */
12534 build_non_dependent_expr (tree expr)
12538 /* Preserve null pointer constants so that the type of things like
12539 "p == 0" where "p" is a pointer can be determined. */
12540 if (null_ptr_cst_p (expr))
12542 /* Preserve OVERLOADs; the functions must be available to resolve
12544 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12545 TREE_OPERAND (expr, 0) : expr);
12546 if (is_overloaded_fn (inner_expr)
12547 || TREE_CODE (inner_expr) == OFFSET_REF)
12549 /* There is no need to return a proxy for a variable. */
12550 if (TREE_CODE (expr) == VAR_DECL)
12552 /* Preserve string constants; conversions from string constants to
12553 "char *" are allowed, even though normally a "const char *"
12554 cannot be used to initialize a "char *". */
12555 if (TREE_CODE (expr) == STRING_CST)
12557 /* Preserve arithmetic constants, as an optimization -- there is no
12558 reason to create a new node. */
12559 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12561 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12562 There is at least one place where we want to know that a
12563 particular expression is a throw-expression: when checking a ?:
12564 expression, there are special rules if the second or third
12565 argument is a throw-expression. */
12566 if (TREE_CODE (expr) == THROW_EXPR)
12569 if (TREE_CODE (expr) == COND_EXPR)
12570 return build3 (COND_EXPR,
12572 TREE_OPERAND (expr, 0),
12573 (TREE_OPERAND (expr, 1)
12574 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12575 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12576 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12577 if (TREE_CODE (expr) == COMPOUND_EXPR
12578 && !COMPOUND_EXPR_OVERLOADED (expr))
12579 return build2 (COMPOUND_EXPR,
12581 TREE_OPERAND (expr, 0),
12582 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12584 /* Otherwise, build a NON_DEPENDENT_EXPR.
12586 REFERENCE_TYPEs are not stripped for expressions in templates
12587 because doing so would play havoc with mangling. Consider, for
12590 template <typename T> void f<T& g>() { g(); }
12592 In the body of "f", the expression for "g" will have
12593 REFERENCE_TYPE, even though the standard says that it should
12594 not. The reason is that we must preserve the syntactic form of
12595 the expression so that mangling (say) "f<g>" inside the body of
12596 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12598 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12601 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12602 Return a new TREE_LIST with the various arguments replaced with
12603 equivalent non-dependent expressions. */
12606 build_non_dependent_args (tree args)
12611 new_args = NULL_TREE;
12612 for (a = args; a; a = TREE_CHAIN (a))
12613 new_args = tree_cons (NULL_TREE,
12614 build_non_dependent_expr (TREE_VALUE (a)),
12616 return nreverse (new_args);
12619 #include "gt-cp-pt.h"