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, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
38 #include "tree-inline.h"
45 #include "tree-iterator.h"
47 /* The type of functions taking a tree, and some additional data, and
49 typedef int (*tree_fn_t) (tree, void*);
51 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
52 instantiations have been deferred, either because their definitions
53 were not yet available, or because we were putting off doing the work.
54 The TREE_PURPOSE of each entry is either a DECL (for a function or
55 static data member), or a TYPE (for a class) indicating what we are
56 hoping to instantiate. The TREE_VALUE is not used. */
57 static GTY(()) tree pending_templates;
58 static GTY(()) tree last_pending_template;
60 int processing_template_parmlist;
61 static int template_header_count;
63 static GTY(()) tree saved_trees;
64 static GTY(()) varray_type inline_parm_levels;
65 static size_t inline_parm_levels_used;
67 static GTY(()) tree current_tinst_level;
69 static GTY(()) tree saved_access_scope;
71 /* Live only within one (recursive) call to tsubst_expr. We use
72 this to pass the statement expression node from the STMT_EXPR
73 to the EXPR_STMT that is its result. */
74 static tree cur_stmt_expr;
76 /* A map from local variable declarations in the body of the template
77 presently being instantiated to the corresponding instantiated
79 static htab_t local_specializations;
81 #define UNIFY_ALLOW_NONE 0
82 #define UNIFY_ALLOW_MORE_CV_QUAL 1
83 #define UNIFY_ALLOW_LESS_CV_QUAL 2
84 #define UNIFY_ALLOW_DERIVED 4
85 #define UNIFY_ALLOW_INTEGER 8
86 #define UNIFY_ALLOW_OUTER_LEVEL 16
87 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
88 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
89 #define UNIFY_ALLOW_MAX_CORRECTION 128
91 static void push_access_scope (tree);
92 static void pop_access_scope (tree);
93 static int resolve_overloaded_unification (tree, tree, tree, tree,
94 unification_kind_t, int);
95 static int try_one_overload (tree, tree, tree, tree, tree,
96 unification_kind_t, int, bool);
97 static int unify (tree, tree, tree, tree, int);
98 static void add_pending_template (tree);
99 static void reopen_tinst_level (tree);
100 static tree classtype_mangled_name (tree);
101 static char* mangle_class_name_for_template (const char *, tree, tree);
102 static tree tsubst_initializer_list (tree, tree);
103 static tree get_class_bindings (tree, tree, tree);
104 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
105 static void tsubst_enum (tree, tree, tree);
106 static tree add_to_template_args (tree, tree);
107 static tree add_outermost_template_args (tree, tree);
108 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
109 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
110 static int type_unification_real (tree, tree, tree, tree,
111 int, unification_kind_t, int, int);
112 static void note_template_header (int);
113 static tree convert_nontype_argument_function (tree, tree);
114 static tree convert_nontype_argument (tree, tree);
115 static tree convert_template_argument (tree, tree, tree,
116 tsubst_flags_t, int, tree);
117 static tree get_bindings_overload (tree, tree, tree);
118 static int for_each_template_parm (tree, tree_fn_t, void*,
119 struct pointer_set_t*);
120 static tree build_template_parm_index (int, int, int, tree, tree);
121 static int inline_needs_template_parms (tree);
122 static void push_inline_template_parms_recursive (tree, int);
123 static tree retrieve_local_specialization (tree);
124 static void register_local_specialization (tree, tree);
125 static tree reduce_template_parm_level (tree, tree, int);
126 static int mark_template_parm (tree, void *);
127 static int template_parm_this_level_p (tree, void *);
128 static tree tsubst_friend_function (tree, tree);
129 static tree tsubst_friend_class (tree, tree);
130 static int can_complete_type_without_circularity (tree);
131 static tree get_bindings (tree, tree, tree);
132 static tree get_bindings_real (tree, tree, tree, int, int, int);
133 static int template_decl_level (tree);
134 static int check_cv_quals_for_unify (int, tree, tree);
135 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
136 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
137 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
138 static void regenerate_decl_from_template (tree, tree);
139 static tree most_specialized (tree, tree, tree);
140 static tree most_specialized_class (tree, tree);
141 static int template_class_depth_real (tree, int);
142 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
143 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
144 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
145 static void check_specialization_scope (void);
146 static tree process_partial_specialization (tree);
147 static void set_current_access_from_decl (tree);
148 static void check_default_tmpl_args (tree, tree, int, int);
149 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
150 static tree get_template_base (tree, tree, tree, tree);
151 static int verify_class_unification (tree, tree, tree);
152 static tree try_class_unification (tree, tree, tree, tree);
153 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
155 static tree determine_specialization (tree, tree, tree *, int, int);
156 static int template_args_equal (tree, tree);
157 static void tsubst_default_arguments (tree);
158 static tree for_each_template_parm_r (tree *, int *, void *);
159 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
160 static void copy_default_args_to_explicit_spec (tree);
161 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
162 static int eq_local_specializations (const void *, const void *);
163 static bool dependent_type_p_r (tree);
164 static tree tsubst (tree, tree, tsubst_flags_t, tree);
165 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
166 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
168 /* Make the current scope suitable for access checking when we are
169 processing T. T can be FUNCTION_DECL for instantiated function
170 template, or VAR_DECL for static member variable (need by
171 instantiate_decl). */
174 push_access_scope (tree t)
176 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
177 || TREE_CODE (t) == VAR_DECL);
179 if (DECL_FRIEND_CONTEXT (t))
180 push_nested_class (DECL_FRIEND_CONTEXT (t));
181 else if (DECL_CLASS_SCOPE_P (t))
182 push_nested_class (DECL_CONTEXT (t));
184 push_to_top_level ();
186 if (TREE_CODE (t) == FUNCTION_DECL)
188 saved_access_scope = tree_cons
189 (NULL_TREE, current_function_decl, saved_access_scope);
190 current_function_decl = t;
194 /* Restore the scope set up by push_access_scope. T is the node we
198 pop_access_scope (tree t)
200 if (TREE_CODE (t) == FUNCTION_DECL)
202 current_function_decl = TREE_VALUE (saved_access_scope);
203 saved_access_scope = TREE_CHAIN (saved_access_scope);
206 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
209 pop_from_top_level ();
212 /* Do any processing required when DECL (a member template
213 declaration) is finished. Returns the TEMPLATE_DECL corresponding
214 to DECL, unless it is a specialization, in which case the DECL
215 itself is returned. */
218 finish_member_template_decl (tree decl)
220 if (decl == error_mark_node)
221 return error_mark_node;
223 gcc_assert (DECL_P (decl));
225 if (TREE_CODE (decl) == TYPE_DECL)
229 type = TREE_TYPE (decl);
230 if (IS_AGGR_TYPE (type)
231 && CLASSTYPE_TEMPLATE_INFO (type)
232 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
234 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
235 check_member_template (tmpl);
240 else if (TREE_CODE (decl) == FIELD_DECL)
241 error ("data member %qD cannot be a member template", decl);
242 else if (DECL_TEMPLATE_INFO (decl))
244 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
246 check_member_template (DECL_TI_TEMPLATE (decl));
247 return DECL_TI_TEMPLATE (decl);
253 error ("invalid member template declaration %qD", decl);
255 return error_mark_node;
258 /* Returns the template nesting level of the indicated class TYPE.
268 A<T>::B<U> has depth two, while A<T> has depth one.
269 Both A<T>::B<int> and A<int>::B<U> have depth one, if
270 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
273 This function is guaranteed to return 0 if passed NULL_TREE so
274 that, for example, `template_class_depth (current_class_type)' is
278 template_class_depth_real (tree type, int count_specializations)
283 type && TREE_CODE (type) != NAMESPACE_DECL;
284 type = (TREE_CODE (type) == FUNCTION_DECL)
285 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
287 if (TREE_CODE (type) != FUNCTION_DECL)
289 if (CLASSTYPE_TEMPLATE_INFO (type)
290 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
291 && ((count_specializations
292 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
293 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
298 if (DECL_TEMPLATE_INFO (type)
299 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
300 && ((count_specializations
301 && DECL_TEMPLATE_SPECIALIZATION (type))
302 || uses_template_parms (DECL_TI_ARGS (type))))
310 /* Returns the template nesting level of the indicated class TYPE.
311 Like template_class_depth_real, but instantiations do not count in
315 template_class_depth (tree type)
317 return template_class_depth_real (type, /*count_specializations=*/0);
320 /* Returns 1 if processing DECL as part of do_pending_inlines
321 needs us to push template parms. */
324 inline_needs_template_parms (tree decl)
326 if (! DECL_TEMPLATE_INFO (decl))
329 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
330 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
333 /* Subroutine of maybe_begin_member_template_processing.
334 Push the template parms in PARMS, starting from LEVELS steps into the
335 chain, and ending at the beginning, since template parms are listed
339 push_inline_template_parms_recursive (tree parmlist, int levels)
341 tree parms = TREE_VALUE (parmlist);
345 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
347 ++processing_template_decl;
348 current_template_parms
349 = tree_cons (size_int (processing_template_decl),
350 parms, current_template_parms);
351 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
353 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
355 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
357 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
358 gcc_assert (DECL_P (parm));
360 switch (TREE_CODE (parm))
369 /* Make a CONST_DECL as is done in process_template_parm.
370 It is ugly that we recreate this here; the original
371 version built in process_template_parm is no longer
373 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
375 DECL_ARTIFICIAL (decl) = 1;
376 TREE_CONSTANT (decl) = 1;
377 TREE_INVARIANT (decl) = 1;
378 TREE_READONLY (decl) = 1;
379 DECL_INITIAL (decl) = DECL_INITIAL (parm);
380 SET_DECL_TEMPLATE_PARM_P (decl);
391 /* Restore the template parameter context for a member template or
392 a friend template defined in a class definition. */
395 maybe_begin_member_template_processing (tree decl)
400 if (inline_needs_template_parms (decl))
402 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
403 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
405 if (DECL_TEMPLATE_SPECIALIZATION (decl))
408 parms = TREE_CHAIN (parms);
411 push_inline_template_parms_recursive (parms, levels);
414 /* Remember how many levels of template parameters we pushed so that
415 we can pop them later. */
416 if (!inline_parm_levels)
417 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
418 if (inline_parm_levels_used == inline_parm_levels->num_elements)
419 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
420 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
421 ++inline_parm_levels_used;
424 /* Undo the effects of begin_member_template_processing. */
427 maybe_end_member_template_processing (void)
431 if (!inline_parm_levels_used)
434 --inline_parm_levels_used;
436 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
439 --processing_template_decl;
440 current_template_parms = TREE_CHAIN (current_template_parms);
445 /* Return a new template argument vector which contains all of ARGS,
446 but has as its innermost set of arguments the EXTRA_ARGS. */
449 add_to_template_args (tree args, tree extra_args)
456 extra_depth = TMPL_ARGS_DEPTH (extra_args);
457 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
459 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
460 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
462 for (j = 1; j <= extra_depth; ++j, ++i)
463 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
468 /* Like add_to_template_args, but only the outermost ARGS are added to
469 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
470 (EXTRA_ARGS) levels are added. This function is used to combine
471 the template arguments from a partial instantiation with the
472 template arguments used to attain the full instantiation from the
473 partial instantiation. */
476 add_outermost_template_args (tree args, tree extra_args)
480 /* If there are more levels of EXTRA_ARGS than there are ARGS,
481 something very fishy is going on. */
482 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
484 /* If *all* the new arguments will be the EXTRA_ARGS, just return
486 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
489 /* For the moment, we make ARGS look like it contains fewer levels. */
490 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
492 new_args = add_to_template_args (args, extra_args);
494 /* Now, we restore ARGS to its full dimensions. */
495 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
500 /* Return the N levels of innermost template arguments from the ARGS. */
503 get_innermost_template_args (tree args, int n)
511 /* If N is 1, just return the innermost set of template arguments. */
513 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
515 /* If we're not removing anything, just return the arguments we were
517 extra_levels = TMPL_ARGS_DEPTH (args) - n;
518 gcc_assert (extra_levels >= 0);
519 if (extra_levels == 0)
522 /* Make a new set of arguments, not containing the outer arguments. */
523 new_args = make_tree_vec (n);
524 for (i = 1; i <= n; ++i)
525 SET_TMPL_ARGS_LEVEL (new_args, i,
526 TMPL_ARGS_LEVEL (args, i + extra_levels));
531 /* We've got a template header coming up; push to a new level for storing
535 begin_template_parm_list (void)
537 /* We use a non-tag-transparent scope here, which causes pushtag to
538 put tags in this scope, rather than in the enclosing class or
539 namespace scope. This is the right thing, since we want
540 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
541 global template class, push_template_decl handles putting the
542 TEMPLATE_DECL into top-level scope. For a nested template class,
545 template <class T> struct S1 {
546 template <class T> struct S2 {};
549 pushtag contains special code to call pushdecl_with_scope on the
550 TEMPLATE_DECL for S2. */
551 begin_scope (sk_template_parms, NULL);
552 ++processing_template_decl;
553 ++processing_template_parmlist;
554 note_template_header (0);
557 /* This routine is called when a specialization is declared. If it is
558 invalid to declare a specialization here, an error is reported. */
561 check_specialization_scope (void)
563 tree scope = current_scope ();
567 An explicit specialization shall be declared in the namespace of
568 which the template is a member, or, for member templates, in the
569 namespace of which the enclosing class or enclosing class
570 template is a member. An explicit specialization of a member
571 function, member class or static data member of a class template
572 shall be declared in the namespace of which the class template
574 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
575 error ("explicit specialization in non-namespace scope %qD", scope);
579 In an explicit specialization declaration for a member of a class
580 template or a member template that appears in namespace scope,
581 the member template and some of its enclosing class templates may
582 remain unspecialized, except that the declaration shall not
583 explicitly specialize a class member template if its enclosing
584 class templates are not explicitly specialized as well. */
585 if (current_template_parms)
586 error ("enclosing class templates are not explicitly specialized");
589 /* We've just seen template <>. */
592 begin_specialization (void)
594 begin_scope (sk_template_spec, NULL);
595 note_template_header (1);
596 check_specialization_scope ();
599 /* Called at then end of processing a declaration preceded by
603 end_specialization (void)
606 reset_specialization ();
609 /* Any template <>'s that we have seen thus far are not referring to a
610 function specialization. */
613 reset_specialization (void)
615 processing_specialization = 0;
616 template_header_count = 0;
619 /* We've just seen a template header. If SPECIALIZATION is nonzero,
620 it was of the form template <>. */
623 note_template_header (int specialization)
625 processing_specialization = specialization;
626 template_header_count++;
629 /* We're beginning an explicit instantiation. */
632 begin_explicit_instantiation (void)
634 gcc_assert (!processing_explicit_instantiation);
635 processing_explicit_instantiation = true;
640 end_explicit_instantiation (void)
642 gcc_assert (processing_explicit_instantiation);
643 processing_explicit_instantiation = false;
646 /* A explicit specialization or partial specialization TMPL is being
647 declared. Check that the namespace in which the specialization is
648 occurring is permissible. Returns false iff it is invalid to
649 specialize TMPL in the current namespace. */
652 check_specialization_namespace (tree tmpl)
654 tree tpl_ns = decl_namespace_context (tmpl);
658 An explicit specialization shall be declared in the namespace of
659 which the template is a member, or, for member templates, in the
660 namespace of which the enclosing class or enclosing class
661 template is a member. An explicit specialization of a member
662 function, member class or static data member of a class template
663 shall be declared in the namespace of which the class template is
665 if (is_associated_namespace (current_namespace, tpl_ns))
666 /* Same or super-using namespace. */
670 pedwarn ("specialization of %qD in different namespace", tmpl);
671 cp_pedwarn_at (" from definition of %q#D", tmpl);
676 /* The TYPE is being declared. If it is a template type, that means it
677 is a partial specialization. Do appropriate error-checking. */
680 maybe_process_partial_specialization (tree type)
682 /* TYPE maybe an ERROR_MARK_NODE. */
683 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
685 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
687 /* This is for ordinary explicit specialization and partial
688 specialization of a template class such as:
690 template <> class C<int>;
694 template <class T> class C<T*>;
696 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
698 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
699 && !COMPLETE_TYPE_P (type))
701 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
702 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
703 if (processing_template_decl)
704 push_template_decl (TYPE_MAIN_DECL (type));
706 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
707 error ("specialization of %qT after instantiation", type);
709 else if (CLASS_TYPE_P (type)
710 && !CLASSTYPE_USE_TEMPLATE (type)
711 && CLASSTYPE_TEMPLATE_INFO (type)
712 && context && CLASS_TYPE_P (context)
713 && CLASSTYPE_TEMPLATE_INFO (context))
715 /* This is for an explicit specialization of member class
716 template according to [temp.expl.spec/18]:
718 template <> template <class U> class C<int>::D;
720 The context `C<int>' must be an implicit instantiation.
721 Otherwise this is just a member class template declared
724 template <> class C<int> { template <class U> class D; };
725 template <> template <class U> class C<int>::D;
727 In the first case, `C<int>::D' is a specialization of `C<T>::D'
728 while in the second case, `C<int>::D' is a primary template
729 and `C<T>::D' may not exist. */
731 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
732 && !COMPLETE_TYPE_P (type))
736 if (current_namespace
737 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
739 pedwarn ("specializing %q#T in different namespace", type);
740 cp_pedwarn_at (" from definition of %q#D",
741 CLASSTYPE_TI_TEMPLATE (type));
744 /* Check for invalid specialization after instantiation:
746 template <> template <> class C<int>::D<int>;
747 template <> template <class U> class C<int>::D; */
749 for (t = DECL_TEMPLATE_INSTANTIATIONS
750 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
751 t; t = TREE_CHAIN (t))
752 if (TREE_VALUE (t) != type
753 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
754 error ("specialization %qT after instantiation %qT",
755 type, TREE_VALUE (t));
757 /* Mark TYPE as a specialization. And as a result, we only
758 have one level of template argument for the innermost
760 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
761 CLASSTYPE_TI_ARGS (type)
762 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
765 else if (processing_specialization)
766 error ("explicit specialization of non-template %qT", type);
769 /* Returns nonzero if we can optimize the retrieval of specializations
770 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
771 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
774 optimize_specialization_lookup_p (tree tmpl)
776 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
777 && DECL_CLASS_SCOPE_P (tmpl)
778 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
780 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
781 /* The optimized lookup depends on the fact that the
782 template arguments for the member function template apply
783 purely to the containing class, which is not true if the
784 containing class is an explicit or partial
786 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
787 && !DECL_MEMBER_TEMPLATE_P (tmpl)
788 && !DECL_CONV_FN_P (tmpl)
789 /* It is possible to have a template that is not a member
790 template and is not a member of a template class:
792 template <typename T>
793 struct S { friend A::f(); };
795 Here, the friend function is a template, but the context does
796 not have template information. The optimized lookup relies
797 on having ARGS be the template arguments for both the class
798 and the function template. */
799 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
802 /* Retrieve the specialization (in the sense of [temp.spec] - a
803 specialization is either an instantiation or an explicit
804 specialization) of TMPL for the given template ARGS. If there is
805 no such specialization, return NULL_TREE. The ARGS are a vector of
806 arguments, or a vector of vectors of arguments, in the case of
807 templates with more than one level of parameters.
809 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
810 then we search for a partial specialization matching ARGS. This
811 parameter is ignored if TMPL is not a class template. */
814 retrieve_specialization (tree tmpl, tree args,
815 bool class_specializations_p)
817 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
819 /* There should be as many levels of arguments as there are
820 levels of parameters. */
821 gcc_assert (TMPL_ARGS_DEPTH (args)
822 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
824 if (optimize_specialization_lookup_p (tmpl))
827 tree class_specialization;
832 /* The template arguments actually apply to the containing
833 class. Find the class specialization with those
835 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
837 = retrieve_specialization (class_template, args,
838 /*class_specializations_p=*/false);
839 if (!class_specialization)
841 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
842 for the specialization. */
843 idx = class_method_index_for_fn (class_specialization, tmpl);
846 /* Iterate through the methods with the indicated name, looking
847 for the one that has an instance of TMPL. */
848 methods = CLASSTYPE_METHOD_VEC (class_specialization);
849 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
851 tree fn = OVL_CURRENT (fns);
852 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
862 /* Class templates store their instantiations on the
863 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
864 DECL_TEMPLATE_SPECIALIZATIONS list. */
865 if (!class_specializations_p
866 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
867 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
869 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
871 /* Iterate through the list until we find a matching template. */
872 while (*sp != NULL_TREE)
876 if (comp_template_args (TREE_PURPOSE (spec), args))
878 /* Use the move-to-front heuristic to speed up future
882 *sp = TREE_CHAIN (*sp);
883 TREE_CHAIN (spec) = *head;
886 return TREE_VALUE (spec);
888 sp = &TREE_CHAIN (spec);
895 /* Like retrieve_specialization, but for local declarations. */
898 retrieve_local_specialization (tree tmpl)
900 tree spec = htab_find_with_hash (local_specializations, tmpl,
901 htab_hash_pointer (tmpl));
902 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
905 /* Returns nonzero iff DECL is a specialization of TMPL. */
908 is_specialization_of (tree decl, tree tmpl)
912 if (TREE_CODE (decl) == FUNCTION_DECL)
916 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
922 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
924 for (t = TREE_TYPE (decl);
926 t = CLASSTYPE_USE_TEMPLATE (t)
927 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
928 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
935 /* Returns nonzero iff DECL is a specialization of friend declaration
936 FRIEND according to [temp.friend]. */
939 is_specialization_of_friend (tree decl, tree friend)
941 bool need_template = true;
944 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
945 || TREE_CODE (decl) == TYPE_DECL);
947 /* For [temp.friend/6] when FRIEND is an ordinary member function
948 of a template class, we want to check if DECL is a specialization
950 if (TREE_CODE (friend) == FUNCTION_DECL
951 && DECL_TEMPLATE_INFO (friend)
952 && !DECL_USE_TEMPLATE (friend))
954 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
955 friend = DECL_TI_TEMPLATE (friend);
956 need_template = false;
958 else if (TREE_CODE (friend) == TEMPLATE_DECL
959 && !PRIMARY_TEMPLATE_P (friend))
960 need_template = false;
962 /* There is nothing to do if this is not a template friend. */
963 if (TREE_CODE (friend) != TEMPLATE_DECL)
966 if (is_specialization_of (decl, friend))
970 A member of a class template may be declared to be a friend of a
971 non-template class. In this case, the corresponding member of
972 every specialization of the class template is a friend of the
973 class granting friendship.
975 For example, given a template friend declaration
977 template <class T> friend void A<T>::f();
979 the member function below is considered a friend
981 template <> struct A<int> {
985 For this type of template friend, TEMPLATE_DEPTH below will be
986 nonzero. To determine if DECL is a friend of FRIEND, we first
987 check if the enclosing class is a specialization of another. */
989 template_depth = template_class_depth (DECL_CONTEXT (friend));
991 && DECL_CLASS_SCOPE_P (decl)
992 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
993 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
995 /* Next, we check the members themselves. In order to handle
996 a few tricky cases, such as when FRIEND's are
998 template <class T> friend void A<T>::g(T t);
999 template <class T> template <T t> friend void A<T>::h();
1003 void A<int>::g(int);
1004 template <int> void A<int>::h();
1006 we need to figure out ARGS, the template arguments from
1007 the context of DECL. This is required for template substitution
1008 of `T' in the function parameter of `g' and template parameter
1009 of `h' in the above examples. Here ARGS corresponds to `int'. */
1011 tree context = DECL_CONTEXT (decl);
1012 tree args = NULL_TREE;
1013 int current_depth = 0;
1015 while (current_depth < template_depth)
1017 if (CLASSTYPE_TEMPLATE_INFO (context))
1019 if (current_depth == 0)
1020 args = TYPE_TI_ARGS (context);
1022 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1025 context = TYPE_CONTEXT (context);
1028 if (TREE_CODE (decl) == FUNCTION_DECL)
1033 tree friend_args_type;
1034 tree decl_args_type;
1036 /* Make sure that both DECL and FRIEND are templates or
1038 is_template = DECL_TEMPLATE_INFO (decl)
1039 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1040 if (need_template ^ is_template)
1042 else if (is_template)
1044 /* If both are templates, check template parameter list. */
1046 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1048 if (!comp_template_parms
1049 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1053 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1056 decl_type = TREE_TYPE (decl);
1058 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1059 tf_none, NULL_TREE);
1060 if (friend_type == error_mark_node)
1063 /* Check if return types match. */
1064 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1067 /* Check if function parameter types match, ignoring the
1068 `this' parameter. */
1069 friend_args_type = TYPE_ARG_TYPES (friend_type);
1070 decl_args_type = TYPE_ARG_TYPES (decl_type);
1071 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1072 friend_args_type = TREE_CHAIN (friend_args_type);
1073 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1074 decl_args_type = TREE_CHAIN (decl_args_type);
1076 return compparms (decl_args_type, friend_args_type);
1080 /* DECL is a TYPE_DECL */
1082 tree decl_type = TREE_TYPE (decl);
1084 /* Make sure that both DECL and FRIEND are templates or
1087 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1088 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1090 if (need_template ^ is_template)
1092 else if (is_template)
1095 /* If both are templates, check the name of the two
1096 TEMPLATE_DECL's first because is_friend didn't. */
1097 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1098 != DECL_NAME (friend))
1101 /* Now check template parameter list. */
1103 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1105 return comp_template_parms
1106 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1110 return (DECL_NAME (decl)
1111 == DECL_NAME (friend));
1117 /* Register the specialization SPEC as a specialization of TMPL with
1118 the indicated ARGS. Returns SPEC, or an equivalent prior
1119 declaration, if available. */
1122 register_specialization (tree spec, tree tmpl, tree args)
1126 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1128 if (TREE_CODE (spec) == FUNCTION_DECL
1129 && uses_template_parms (DECL_TI_ARGS (spec)))
1130 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1131 register it; we want the corresponding TEMPLATE_DECL instead.
1132 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1133 the more obvious `uses_template_parms (spec)' to avoid problems
1134 with default function arguments. In particular, given
1135 something like this:
1137 template <class T> void f(T t1, T t = T())
1139 the default argument expression is not substituted for in an
1140 instantiation unless and until it is actually needed. */
1143 /* There should be as many levels of arguments as there are
1144 levels of parameters. */
1145 gcc_assert (TMPL_ARGS_DEPTH (args)
1146 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
1148 fn = retrieve_specialization (tmpl, args,
1149 /*class_specializations_p=*/false);
1150 /* We can sometimes try to re-register a specialization that we've
1151 already got. In particular, regenerate_decl_from_template calls
1152 duplicate_decls which will update the specialization list. But,
1153 we'll still get called again here anyhow. It's more convenient
1154 to simply allow this than to try to prevent it. */
1157 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1159 if (DECL_TEMPLATE_INSTANTIATION (fn))
1162 || DECL_EXPLICIT_INSTANTIATION (fn))
1164 error ("specialization of %qD after instantiation",
1170 /* This situation should occur only if the first
1171 specialization is an implicit instantiation, the
1172 second is an explicit specialization, and the
1173 implicit instantiation has not yet been used. That
1174 situation can occur if we have implicitly
1175 instantiated a member function and then specialized
1178 We can also wind up here if a friend declaration that
1179 looked like an instantiation turns out to be a
1182 template <class T> void foo(T);
1183 class S { friend void foo<>(int) };
1184 template <> void foo(int);
1186 We transform the existing DECL in place so that any
1187 pointers to it become pointers to the updated
1190 If there was a definition for the template, but not
1191 for the specialization, we want this to look as if
1192 there were no definition, and vice versa. */
1193 DECL_INITIAL (fn) = NULL_TREE;
1194 duplicate_decls (spec, fn);
1199 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1201 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
1202 /* Dup decl failed, but this is a new definition. Set the
1203 line number so any errors match this new
1205 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1211 /* A specialization must be declared in the same namespace as the
1212 template it is specializing. */
1213 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1214 && !check_specialization_namespace (tmpl))
1215 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1217 if (!optimize_specialization_lookup_p (tmpl))
1218 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1219 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1224 /* Unregister the specialization SPEC as a specialization of TMPL.
1225 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1226 if the SPEC was listed as a specialization of TMPL. */
1229 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1233 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1235 s = &TREE_CHAIN (*s))
1236 if (TREE_VALUE (*s) == spec)
1239 *s = TREE_CHAIN (*s);
1241 TREE_VALUE (*s) = new_spec;
1248 /* Compare an entry in the local specializations hash table P1 (which
1249 is really a pointer to a TREE_LIST) with P2 (which is really a
1253 eq_local_specializations (const void *p1, const void *p2)
1255 return TREE_VALUE ((tree) p1) == (tree) p2;
1258 /* Hash P1, an entry in the local specializations table. */
1261 hash_local_specialization (const void* p1)
1263 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1266 /* Like register_specialization, but for local declarations. We are
1267 registering SPEC, an instantiation of TMPL. */
1270 register_local_specialization (tree spec, tree tmpl)
1274 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1275 htab_hash_pointer (tmpl), INSERT);
1276 *slot = build_tree_list (spec, tmpl);
1279 /* Print the list of candidate FNS in an error message. */
1282 print_candidates (tree fns)
1286 const char *str = "candidates are:";
1288 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1292 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1293 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
1298 /* Returns the template (one of the functions given by TEMPLATE_ID)
1299 which can be specialized to match the indicated DECL with the
1300 explicit template args given in TEMPLATE_ID. The DECL may be
1301 NULL_TREE if none is available. In that case, the functions in
1302 TEMPLATE_ID are non-members.
1304 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1305 specialization of a member template.
1307 The TEMPLATE_COUNT is the number of references to qualifying
1308 template classes that appeared in the name of the function. See
1309 check_explicit_specialization for a more accurate description.
1311 The template args (those explicitly specified and those deduced)
1312 are output in a newly created vector *TARGS_OUT.
1314 If it is impossible to determine the result, an error message is
1315 issued. The error_mark_node is returned to indicate failure. */
1318 determine_specialization (tree template_id,
1321 int need_member_template,
1326 tree explicit_targs;
1327 tree candidates = NULL_TREE;
1328 tree templates = NULL_TREE;
1330 struct cp_binding_level *b;
1332 *targs_out = NULL_TREE;
1334 if (template_id == error_mark_node)
1335 return error_mark_node;
1337 fns = TREE_OPERAND (template_id, 0);
1338 explicit_targs = TREE_OPERAND (template_id, 1);
1340 if (fns == error_mark_node)
1341 return error_mark_node;
1343 /* Check for baselinks. */
1344 if (BASELINK_P (fns))
1345 fns = BASELINK_FUNCTIONS (fns);
1347 if (!is_overloaded_fn (fns))
1349 error ("%qD is not a function template", fns);
1350 return error_mark_node;
1353 /* Count the number of template headers specified for this
1356 for (b = current_binding_level;
1357 b->kind == sk_template_parms || b->kind == sk_template_spec;
1361 for (; fns; fns = OVL_NEXT (fns))
1363 tree fn = OVL_CURRENT (fns);
1365 if (TREE_CODE (fn) == TEMPLATE_DECL)
1367 tree decl_arg_types;
1370 /* DECL might be a specialization of FN. */
1372 /* Adjust the type of DECL in case FN is a static member. */
1373 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1374 if (DECL_STATIC_FUNCTION_P (fn)
1375 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1376 decl_arg_types = TREE_CHAIN (decl_arg_types);
1378 /* Check that the number of function parameters matches.
1380 template <class T> void f(int i = 0);
1381 template <> void f<int>();
1382 The specialization f<int> is invalid but is not caught
1383 by get_bindings below. */
1385 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1386 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1389 /* For a non-static member function, we need to make sure that
1390 the const qualification is the same. This can be done by
1391 checking the 'this' in the argument list. */
1392 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1393 && !same_type_p (TREE_VALUE (fn_arg_types),
1394 TREE_VALUE (decl_arg_types)))
1397 /* In case of explicit specialization, we need to check if
1398 the number of template headers appearing in the specialization
1399 is correct. This is usually done in check_explicit_specialization,
1400 but the check done there cannot be exhaustive when specializing
1401 member functions. Consider the following code:
1403 template <> void A<int>::f(int);
1404 template <> template <> void A<int>::f(int);
1406 Assuming that A<int> is not itself an explicit specialization
1407 already, the first line specializes "f" which is a non-template
1408 member function, whilst the second line specializes "f" which
1409 is a template member function. So both lines are syntactically
1410 correct, and check_explicit_specialization does not reject
1413 Here, we can do better, as we are matching the specialization
1414 against the declarations. We count the number of template
1415 headers, and we check if they match TEMPLATE_COUNT + 1
1416 (TEMPLATE_COUNT is the number of qualifying template classes,
1417 plus there must be another header for the member template
1420 Notice that if header_count is zero, this is not a
1421 specialization but rather a template instantiation, so there
1422 is no check we can perform here. */
1423 if (header_count && header_count != template_count + 1)
1426 /* See whether this function might be a specialization of this
1428 targs = get_bindings (fn, decl, explicit_targs);
1431 /* We cannot deduce template arguments that when used to
1432 specialize TMPL will produce DECL. */
1435 /* Save this template, and the arguments deduced. */
1436 templates = tree_cons (targs, fn, templates);
1438 else if (need_member_template)
1439 /* FN is an ordinary member function, and we need a
1440 specialization of a member template. */
1442 else if (TREE_CODE (fn) != FUNCTION_DECL)
1443 /* We can get IDENTIFIER_NODEs here in certain erroneous
1446 else if (!DECL_FUNCTION_MEMBER_P (fn))
1447 /* This is just an ordinary non-member function. Nothing can
1448 be a specialization of that. */
1450 else if (DECL_ARTIFICIAL (fn))
1451 /* Cannot specialize functions that are created implicitly. */
1455 tree decl_arg_types;
1457 /* This is an ordinary member function. However, since
1458 we're here, we can assume it's enclosing class is a
1459 template class. For example,
1461 template <typename T> struct S { void f(); };
1462 template <> void S<int>::f() {}
1464 Here, S<int>::f is a non-template, but S<int> is a
1465 template class. If FN has the same type as DECL, we
1466 might be in business. */
1468 if (!DECL_TEMPLATE_INFO (fn))
1469 /* Its enclosing class is an explicit specialization
1470 of a template class. This is not a candidate. */
1473 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1474 TREE_TYPE (TREE_TYPE (fn))))
1475 /* The return types differ. */
1478 /* Adjust the type of DECL in case FN is a static member. */
1479 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1480 if (DECL_STATIC_FUNCTION_P (fn)
1481 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1482 decl_arg_types = TREE_CHAIN (decl_arg_types);
1484 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1487 candidates = tree_cons (NULL_TREE, fn, candidates);
1491 if (templates && TREE_CHAIN (templates))
1497 It is possible for a specialization with a given function
1498 signature to be instantiated from more than one function
1499 template. In such cases, explicit specification of the
1500 template arguments must be used to uniquely identify the
1501 function template specialization being specialized.
1503 Note that here, there's no suggestion that we're supposed to
1504 determine which of the candidate templates is most
1505 specialized. However, we, also have:
1509 Partial ordering of overloaded function template
1510 declarations is used in the following contexts to select
1511 the function template to which a function template
1512 specialization refers:
1514 -- when an explicit specialization refers to a function
1517 So, we do use the partial ordering rules, at least for now.
1518 This extension can only serve to make invalid programs valid,
1519 so it's safe. And, there is strong anecdotal evidence that
1520 the committee intended the partial ordering rules to apply;
1521 the EDG front-end has that behavior, and John Spicer claims
1522 that the committee simply forgot to delete the wording in
1523 [temp.expl.spec]. */
1524 tree tmpl = most_specialized (templates, decl, explicit_targs);
1525 if (tmpl && tmpl != error_mark_node)
1527 targs = get_bindings (tmpl, decl, explicit_targs);
1528 templates = tree_cons (targs, tmpl, NULL_TREE);
1532 if (templates == NULL_TREE && candidates == NULL_TREE)
1534 cp_error_at ("template-id %qD for %q+D does not match any template "
1537 return error_mark_node;
1539 else if ((templates && TREE_CHAIN (templates))
1540 || (candidates && TREE_CHAIN (candidates))
1541 || (templates && candidates))
1543 cp_error_at ("ambiguous template specialization %qD for %q+D",
1545 chainon (candidates, templates);
1546 print_candidates (candidates);
1547 return error_mark_node;
1550 /* We have one, and exactly one, match. */
1553 /* It was a specialization of an ordinary member function in a
1555 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1556 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1559 /* It was a specialization of a template. */
1560 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1561 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1563 *targs_out = copy_node (targs);
1564 SET_TMPL_ARGS_LEVEL (*targs_out,
1565 TMPL_ARGS_DEPTH (*targs_out),
1566 TREE_PURPOSE (templates));
1569 *targs_out = TREE_PURPOSE (templates);
1570 return TREE_VALUE (templates);
1573 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1574 but with the default argument values filled in from those in the
1578 copy_default_args_to_explicit_spec_1 (tree spec_types,
1581 tree new_spec_types;
1586 if (spec_types == void_list_node)
1587 return void_list_node;
1589 /* Substitute into the rest of the list. */
1591 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1592 TREE_CHAIN (tmpl_types));
1594 /* Add the default argument for this parameter. */
1595 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1596 TREE_VALUE (spec_types),
1600 /* DECL is an explicit specialization. Replicate default arguments
1601 from the template it specializes. (That way, code like:
1603 template <class T> void f(T = 3);
1604 template <> void f(double);
1607 works, as required.) An alternative approach would be to look up
1608 the correct default arguments at the call-site, but this approach
1609 is consistent with how implicit instantiations are handled. */
1612 copy_default_args_to_explicit_spec (tree decl)
1617 tree new_spec_types;
1621 tree object_type = NULL_TREE;
1622 tree in_charge = NULL_TREE;
1623 tree vtt = NULL_TREE;
1625 /* See if there's anything we need to do. */
1626 tmpl = DECL_TI_TEMPLATE (decl);
1627 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1628 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1629 if (TREE_PURPOSE (t))
1634 old_type = TREE_TYPE (decl);
1635 spec_types = TYPE_ARG_TYPES (old_type);
1637 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1639 /* Remove the this pointer, but remember the object's type for
1641 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1642 spec_types = TREE_CHAIN (spec_types);
1643 tmpl_types = TREE_CHAIN (tmpl_types);
1645 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1647 /* DECL may contain more parameters than TMPL due to the extra
1648 in-charge parameter in constructors and destructors. */
1649 in_charge = spec_types;
1650 spec_types = TREE_CHAIN (spec_types);
1652 if (DECL_HAS_VTT_PARM_P (decl))
1655 spec_types = TREE_CHAIN (spec_types);
1659 /* Compute the merged default arguments. */
1661 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1663 /* Compute the new FUNCTION_TYPE. */
1667 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1672 /* Put the in-charge parameter back. */
1673 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1674 TREE_VALUE (in_charge),
1677 new_type = build_method_type_directly (object_type,
1678 TREE_TYPE (old_type),
1682 new_type = build_function_type (TREE_TYPE (old_type),
1684 new_type = cp_build_type_attribute_variant (new_type,
1685 TYPE_ATTRIBUTES (old_type));
1686 new_type = build_exception_variant (new_type,
1687 TYPE_RAISES_EXCEPTIONS (old_type));
1688 TREE_TYPE (decl) = new_type;
1691 /* Check to see if the function just declared, as indicated in
1692 DECLARATOR, and in DECL, is a specialization of a function
1693 template. We may also discover that the declaration is an explicit
1694 instantiation at this point.
1696 Returns DECL, or an equivalent declaration that should be used
1697 instead if all goes well. Issues an error message if something is
1698 amiss. Returns error_mark_node if the error is not easily
1701 FLAGS is a bitmask consisting of the following flags:
1703 2: The function has a definition.
1704 4: The function is a friend.
1706 The TEMPLATE_COUNT is the number of references to qualifying
1707 template classes that appeared in the name of the function. For
1710 template <class T> struct S { void f(); };
1713 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1714 classes are not counted in the TEMPLATE_COUNT, so that in
1716 template <class T> struct S {};
1717 template <> struct S<int> { void f(); }
1718 template <> void S<int>::f();
1720 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1721 invalid; there should be no template <>.)
1723 If the function is a specialization, it is marked as such via
1724 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1725 is set up correctly, and it is added to the list of specializations
1726 for that template. */
1729 check_explicit_specialization (tree declarator,
1734 int have_def = flags & 2;
1735 int is_friend = flags & 4;
1736 int specialization = 0;
1737 int explicit_instantiation = 0;
1738 int member_specialization = 0;
1739 tree ctype = DECL_CLASS_CONTEXT (decl);
1740 tree dname = DECL_NAME (decl);
1745 if (!processing_specialization)
1748 tsk = tsk_excessive_parms;
1751 tsk = current_tmpl_spec_kind (template_count);
1756 if (processing_specialization)
1759 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1761 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1764 /* This could be something like:
1766 template <class T> void f(T);
1767 class S { friend void f<>(int); } */
1771 /* This case handles bogus declarations like template <>
1772 template <class T> void f<int>(); */
1774 error ("template-id %qD in declaration of primary template",
1781 case tsk_invalid_member_spec:
1782 /* The error has already been reported in
1783 check_specialization_scope. */
1784 return error_mark_node;
1786 case tsk_invalid_expl_inst:
1787 error ("template parameter list used in explicit instantiation");
1793 error ("definition provided for explicit instantiation");
1795 explicit_instantiation = 1;
1798 case tsk_excessive_parms:
1799 case tsk_insufficient_parms:
1800 if (tsk == tsk_excessive_parms)
1801 error ("too many template parameter lists in declaration of %qD",
1803 else if (template_header_count)
1804 error("too few template parameter lists in declaration of %qD", decl);
1806 error("explicit specialization of %qD must be introduced by "
1807 "%<template <>%>", decl);
1811 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1813 member_specialization = 1;
1819 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1821 /* This case handles bogus declarations like template <>
1822 template <class T> void f<int>(); */
1824 if (uses_template_parms (declarator))
1825 error ("function template partial specialization %qD "
1826 "is not allowed", declarator);
1828 error ("template-id %qD in declaration of primary template",
1833 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1834 /* This is a specialization of a member template, without
1835 specialization the containing class. Something like:
1837 template <class T> struct S {
1838 template <class U> void f (U);
1840 template <> template <class U> void S<int>::f(U) {}
1842 That's a specialization -- but of the entire template. */
1850 if (specialization || member_specialization)
1852 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1853 for (; t; t = TREE_CHAIN (t))
1854 if (TREE_PURPOSE (t))
1857 ("default argument specified in explicit specialization");
1860 if (current_lang_name == lang_name_c)
1861 error ("template specialization with C linkage");
1864 if (specialization || member_specialization || explicit_instantiation)
1866 tree tmpl = NULL_TREE;
1867 tree targs = NULL_TREE;
1869 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1870 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1874 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1879 /* If there is no class context, the explicit instantiation
1880 must be at namespace scope. */
1881 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1883 /* Find the namespace binding, using the declaration
1885 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1888 declarator = lookup_template_function (fns, NULL_TREE);
1891 if (declarator == error_mark_node)
1892 return error_mark_node;
1894 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1896 if (!explicit_instantiation)
1897 /* A specialization in class scope. This is invalid,
1898 but the error will already have been flagged by
1899 check_specialization_scope. */
1900 return error_mark_node;
1903 /* It's not valid to write an explicit instantiation in
1906 class C { template void f(); }
1908 This case is caught by the parser. However, on
1911 template class C { void f(); };
1913 (which is invalid) we can get here. The error will be
1920 else if (ctype != NULL_TREE
1921 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1924 /* Find the list of functions in ctype that have the same
1925 name as the declared function. */
1926 tree name = TREE_OPERAND (declarator, 0);
1927 tree fns = NULL_TREE;
1930 if (constructor_name_p (name, ctype))
1932 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1934 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1935 : !TYPE_HAS_DESTRUCTOR (ctype))
1937 /* From [temp.expl.spec]:
1939 If such an explicit specialization for the member
1940 of a class template names an implicitly-declared
1941 special member function (clause _special_), the
1942 program is ill-formed.
1944 Similar language is found in [temp.explicit]. */
1945 error ("specialization of implicitly-declared special member function");
1946 return error_mark_node;
1949 name = is_constructor ? ctor_identifier : dtor_identifier;
1952 if (!DECL_CONV_FN_P (decl))
1954 idx = lookup_fnfields_1 (ctype, name);
1956 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1963 /* For a type-conversion operator, we cannot do a
1964 name-based lookup. We might be looking for `operator
1965 int' which will be a specialization of `operator T'.
1966 So, we find *all* the conversion operators, and then
1967 select from them. */
1970 methods = CLASSTYPE_METHOD_VEC (ctype);
1972 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1973 VEC_iterate (tree, methods, idx, ovl);
1976 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1977 /* There are no more conversion functions. */
1980 /* Glue all these conversion functions together
1981 with those we already have. */
1982 for (; ovl; ovl = OVL_NEXT (ovl))
1983 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1987 if (fns == NULL_TREE)
1989 error ("no member function %qD declared in %qT", name, ctype);
1990 return error_mark_node;
1993 TREE_OPERAND (declarator, 0) = fns;
1996 /* Figure out what exactly is being specialized at this point.
1997 Note that for an explicit instantiation, even one for a
1998 member function, we cannot tell apriori whether the
1999 instantiation is for a member template, or just a member
2000 function of a template class. Even if a member template is
2001 being instantiated, the member template arguments may be
2002 elided if they can be deduced from the rest of the
2004 tmpl = determine_specialization (declarator, decl,
2006 member_specialization,
2009 if (!tmpl || tmpl == error_mark_node)
2010 /* We couldn't figure out what this declaration was
2012 return error_mark_node;
2015 tree gen_tmpl = most_general_template (tmpl);
2017 if (explicit_instantiation)
2019 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2020 is done by do_decl_instantiation later. */
2022 int arg_depth = TMPL_ARGS_DEPTH (targs);
2023 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2025 if (arg_depth > parm_depth)
2027 /* If TMPL is not the most general template (for
2028 example, if TMPL is a friend template that is
2029 injected into namespace scope), then there will
2030 be too many levels of TARGS. Remove some of them
2035 new_targs = make_tree_vec (parm_depth);
2036 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2037 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2038 = TREE_VEC_ELT (targs, i);
2042 return instantiate_template (tmpl, targs, tf_error);
2045 /* If we thought that the DECL was a member function, but it
2046 turns out to be specializing a static member function,
2047 make DECL a static member function as well. */
2048 if (DECL_STATIC_FUNCTION_P (tmpl)
2049 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2050 revert_static_member_fn (decl);
2052 /* If this is a specialization of a member template of a
2053 template class. In we want to return the TEMPLATE_DECL,
2054 not the specialization of it. */
2055 if (tsk == tsk_template)
2057 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2058 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2061 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2062 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2063 = DECL_SOURCE_LOCATION (decl);
2064 /* We want to use the argument list specified in the
2065 definition, not in the original declaration. */
2066 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2067 = DECL_ARGUMENTS (decl);
2072 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2073 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2075 /* Inherit default function arguments from the template
2076 DECL is specializing. */
2077 copy_default_args_to_explicit_spec (decl);
2079 /* This specialization has the same protection as the
2080 template it specializes. */
2081 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2082 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2084 if (is_friend && !have_def)
2085 /* This is not really a declaration of a specialization.
2086 It's just the name of an instantiation. But, it's not
2087 a request for an instantiation, either. */
2088 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2089 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2090 /* This is indeed a specialization. In case of constructors
2091 and destructors, we need in-charge and not-in-charge
2092 versions in V3 ABI. */
2093 clone_function_decl (decl, /*update_method_vec_p=*/0);
2095 /* Register this specialization so that we can find it
2097 decl = register_specialization (decl, gen_tmpl, targs);
2104 /* TYPE is being declared. Verify that the use of template headers
2105 and such is reasonable. Issue error messages if not. */
2108 maybe_check_template_type (tree type)
2110 if (template_header_count)
2112 /* We are in the scope of some `template <...>' header. */
2115 = template_class_depth_real (TYPE_CONTEXT (type),
2116 /*count_specializations=*/1);
2118 if (template_header_count <= context_depth)
2119 /* This is OK; the template headers are for the context. We
2120 are actually too lenient here; like
2121 check_explicit_specialization we should consider the number
2122 of template types included in the actual declaration. For
2125 template <class T> struct S {
2126 template <class U> template <class V>
2132 template <class T> struct S {
2133 template <class U> struct I;
2136 template <class T> template <class U.
2141 else if (template_header_count > context_depth + 1)
2142 /* There are two many template parameter lists. */
2143 error ("too many template parameter lists in declaration of %qT", type);
2147 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2148 parameters. These are represented in the same format used for
2149 DECL_TEMPLATE_PARMS. */
2152 comp_template_parms (tree parms1, tree parms2)
2157 if (parms1 == parms2)
2160 for (p1 = parms1, p2 = parms2;
2161 p1 != NULL_TREE && p2 != NULL_TREE;
2162 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2164 tree t1 = TREE_VALUE (p1);
2165 tree t2 = TREE_VALUE (p2);
2168 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2169 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2171 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2174 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2176 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2177 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2179 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2182 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2184 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2189 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2190 /* One set of parameters has more parameters lists than the
2197 /* Complain if DECL shadows a template parameter.
2199 [temp.local]: A template-parameter shall not be redeclared within its
2200 scope (including nested scopes). */
2203 check_template_shadow (tree decl)
2207 /* If we're not in a template, we can't possibly shadow a template
2209 if (!current_template_parms)
2212 /* Figure out what we're shadowing. */
2213 if (TREE_CODE (decl) == OVERLOAD)
2214 decl = OVL_CURRENT (decl);
2215 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2217 /* If there's no previous binding for this name, we're not shadowing
2218 anything, let alone a template parameter. */
2222 /* If we're not shadowing a template parameter, we're done. Note
2223 that OLDDECL might be an OVERLOAD (or perhaps even an
2224 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2226 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2229 /* We check for decl != olddecl to avoid bogus errors for using a
2230 name inside a class. We check TPFI to avoid duplicate errors for
2231 inline member templates. */
2233 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2236 cp_error_at ("declaration of %q#D", decl);
2237 cp_error_at (" shadows template parm %q#D", olddecl);
2240 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2241 ORIG_LEVEL, DECL, and TYPE. */
2244 build_template_parm_index (int index,
2250 tree t = make_node (TEMPLATE_PARM_INDEX);
2251 TEMPLATE_PARM_IDX (t) = index;
2252 TEMPLATE_PARM_LEVEL (t) = level;
2253 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2254 TEMPLATE_PARM_DECL (t) = decl;
2255 TREE_TYPE (t) = type;
2256 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2257 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2258 TREE_READONLY (t) = TREE_READONLY (decl);
2263 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2264 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2265 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2266 new one is created. */
2269 reduce_template_parm_level (tree index, tree type, int levels)
2271 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2272 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2273 != TEMPLATE_PARM_LEVEL (index) - levels))
2275 tree orig_decl = TEMPLATE_PARM_DECL (index);
2278 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2279 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2280 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2281 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2282 DECL_ARTIFICIAL (decl) = 1;
2283 SET_DECL_TEMPLATE_PARM_P (decl);
2285 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2286 TEMPLATE_PARM_LEVEL (index) - levels,
2287 TEMPLATE_PARM_ORIG_LEVEL (index),
2289 TEMPLATE_PARM_DESCENDANTS (index) = t;
2291 /* Template template parameters need this. */
2292 DECL_TEMPLATE_PARMS (decl)
2293 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2296 return TEMPLATE_PARM_DESCENDANTS (index);
2299 /* Process information from new template parameter NEXT and append it to the
2300 LIST being built. This new parameter is a non-type parameter iff
2301 IS_NON_TYPE is true. */
2304 process_template_parm (tree list, tree next, bool is_non_type)
2312 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2313 defval = TREE_PURPOSE (parm);
2317 tree p = TREE_VALUE (tree_last (list));
2319 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2320 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2322 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2330 parm = TREE_VALUE (parm);
2332 SET_DECL_TEMPLATE_PARM_P (parm);
2336 The top-level cv-qualifiers on the template-parameter are
2337 ignored when determining its type. */
2338 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2340 /* A template parameter is not modifiable. */
2341 TREE_CONSTANT (parm) = 1;
2342 TREE_INVARIANT (parm) = 1;
2343 TREE_READONLY (parm) = 1;
2344 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2345 TREE_TYPE (parm) = void_type_node;
2346 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2347 TREE_CONSTANT (decl) = 1;
2348 TREE_INVARIANT (decl) = 1;
2349 TREE_READONLY (decl) = 1;
2350 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2351 = build_template_parm_index (idx, processing_template_decl,
2352 processing_template_decl,
2353 decl, TREE_TYPE (parm));
2358 parm = TREE_VALUE (TREE_VALUE (parm));
2360 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2362 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2363 /* This is for distinguishing between real templates and template
2364 template parameters */
2365 TREE_TYPE (parm) = t;
2366 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2371 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2372 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2373 decl = build_decl (TYPE_DECL, parm, t);
2376 TYPE_NAME (t) = decl;
2377 TYPE_STUB_DECL (t) = decl;
2379 TEMPLATE_TYPE_PARM_INDEX (t)
2380 = build_template_parm_index (idx, processing_template_decl,
2381 processing_template_decl,
2382 decl, TREE_TYPE (parm));
2384 DECL_ARTIFICIAL (decl) = 1;
2385 SET_DECL_TEMPLATE_PARM_P (decl);
2387 parm = build_tree_list (defval, parm);
2388 return chainon (list, parm);
2391 /* The end of a template parameter list has been reached. Process the
2392 tree list into a parameter vector, converting each parameter into a more
2393 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2397 end_template_parm_list (tree parms)
2401 tree saved_parmlist = make_tree_vec (list_length (parms));
2403 current_template_parms
2404 = tree_cons (size_int (processing_template_decl),
2405 saved_parmlist, current_template_parms);
2407 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2409 next = TREE_CHAIN (parm);
2410 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2411 TREE_CHAIN (parm) = NULL_TREE;
2414 --processing_template_parmlist;
2416 return saved_parmlist;
2419 /* end_template_decl is called after a template declaration is seen. */
2422 end_template_decl (void)
2424 reset_specialization ();
2426 if (! processing_template_decl)
2429 /* This matches the pushlevel in begin_template_parm_list. */
2432 --processing_template_decl;
2433 current_template_parms = TREE_CHAIN (current_template_parms);
2436 /* Given a template argument vector containing the template PARMS.
2437 The innermost PARMS are given first. */
2440 current_template_args (void)
2443 tree args = NULL_TREE;
2444 int length = TMPL_PARMS_DEPTH (current_template_parms);
2447 /* If there is only one level of template parameters, we do not
2448 create a TREE_VEC of TREE_VECs. Instead, we return a single
2449 TREE_VEC containing the arguments. */
2451 args = make_tree_vec (length);
2453 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2455 tree a = copy_node (TREE_VALUE (header));
2458 TREE_TYPE (a) = NULL_TREE;
2459 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2461 tree t = TREE_VEC_ELT (a, i);
2463 /* T will be a list if we are called from within a
2464 begin/end_template_parm_list pair, but a vector directly
2465 if within a begin/end_member_template_processing pair. */
2466 if (TREE_CODE (t) == TREE_LIST)
2470 if (TREE_CODE (t) == TYPE_DECL
2471 || TREE_CODE (t) == TEMPLATE_DECL)
2474 t = DECL_INITIAL (t);
2475 TREE_VEC_ELT (a, i) = t;
2480 TREE_VEC_ELT (args, --l) = a;
2488 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2489 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2490 a member template. Used by push_template_decl below. */
2493 build_template_decl (tree decl, tree parms, bool member_template_p)
2495 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2496 DECL_TEMPLATE_PARMS (tmpl) = parms;
2497 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2498 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2499 if (DECL_LANG_SPECIFIC (decl))
2501 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2502 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2503 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2504 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2505 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2506 if (DECL_OVERLOADED_OPERATOR_P (decl))
2507 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2508 DECL_OVERLOADED_OPERATOR_P (decl));
2514 struct template_parm_data
2516 /* The level of the template parameters we are currently
2520 /* The index of the specialization argument we are currently
2524 /* An array whose size is the number of template parameters. The
2525 elements are nonzero if the parameter has been used in any one
2526 of the arguments processed so far. */
2529 /* An array whose size is the number of template arguments. The
2530 elements are nonzero if the argument makes use of template
2531 parameters of this level. */
2532 int* arg_uses_template_parms;
2535 /* Subroutine of push_template_decl used to see if each template
2536 parameter in a partial specialization is used in the explicit
2537 argument list. If T is of the LEVEL given in DATA (which is
2538 treated as a template_parm_data*), then DATA->PARMS is marked
2542 mark_template_parm (tree t, void* data)
2546 struct template_parm_data* tpd = (struct template_parm_data*) data;
2548 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2550 level = TEMPLATE_PARM_LEVEL (t);
2551 idx = TEMPLATE_PARM_IDX (t);
2555 level = TEMPLATE_TYPE_LEVEL (t);
2556 idx = TEMPLATE_TYPE_IDX (t);
2559 if (level == tpd->level)
2561 tpd->parms[idx] = 1;
2562 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2565 /* Return zero so that for_each_template_parm will continue the
2566 traversal of the tree; we want to mark *every* template parm. */
2570 /* Process the partial specialization DECL. */
2573 process_partial_specialization (tree decl)
2575 tree type = TREE_TYPE (decl);
2576 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2577 tree specargs = CLASSTYPE_TI_ARGS (type);
2578 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2579 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2580 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2581 int nargs = TREE_VEC_LENGTH (inner_args);
2582 int ntparms = TREE_VEC_LENGTH (inner_parms);
2584 int did_error_intro = 0;
2585 struct template_parm_data tpd;
2586 struct template_parm_data tpd2;
2588 /* We check that each of the template parameters given in the
2589 partial specialization is used in the argument list to the
2590 specialization. For example:
2592 template <class T> struct S;
2593 template <class T> struct S<T*>;
2595 The second declaration is OK because `T*' uses the template
2596 parameter T, whereas
2598 template <class T> struct S<int>;
2600 is no good. Even trickier is:
2611 The S2<T> declaration is actually invalid; it is a
2612 full-specialization. Of course,
2615 struct S2<T (*)(U)>;
2617 or some such would have been OK. */
2618 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2619 tpd.parms = alloca (sizeof (int) * ntparms);
2620 memset (tpd.parms, 0, sizeof (int) * ntparms);
2622 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2623 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2624 for (i = 0; i < nargs; ++i)
2626 tpd.current_arg = i;
2627 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2628 &mark_template_parm,
2632 for (i = 0; i < ntparms; ++i)
2633 if (tpd.parms[i] == 0)
2635 /* One of the template parms was not used in the
2637 if (!did_error_intro)
2639 error ("template parameters not used in partial specialization:");
2640 did_error_intro = 1;
2643 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2646 /* [temp.class.spec]
2648 The argument list of the specialization shall not be identical to
2649 the implicit argument list of the primary template. */
2650 if (comp_template_args
2652 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2654 error ("partial specialization %qT does not specialize any template arguments", type);
2656 /* [temp.class.spec]
2658 A partially specialized non-type argument expression shall not
2659 involve template parameters of the partial specialization except
2660 when the argument expression is a simple identifier.
2662 The type of a template parameter corresponding to a specialized
2663 non-type argument shall not be dependent on a parameter of the
2665 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2667 for (i = 0; i < nargs; ++i)
2669 tree arg = TREE_VEC_ELT (inner_args, i);
2670 if (/* These first two lines are the `non-type' bit. */
2672 && TREE_CODE (arg) != TEMPLATE_DECL
2673 /* This next line is the `argument expression is not just a
2674 simple identifier' condition and also the `specialized
2675 non-type argument' bit. */
2676 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2678 if (tpd.arg_uses_template_parms[i])
2679 error ("template argument %qE involves template parameter(s)", arg);
2682 /* Look at the corresponding template parameter,
2683 marking which template parameters its type depends
2686 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2691 /* We haven't yet initialized TPD2. Do so now. */
2692 tpd2.arg_uses_template_parms
2693 = alloca (sizeof (int) * nargs);
2694 /* The number of parameters here is the number in the
2695 main template, which, as checked in the assertion
2697 tpd2.parms = alloca (sizeof (int) * nargs);
2699 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2702 /* Mark the template parameters. But this time, we're
2703 looking for the template parameters of the main
2704 template, not in the specialization. */
2705 tpd2.current_arg = i;
2706 tpd2.arg_uses_template_parms[i] = 0;
2707 memset (tpd2.parms, 0, sizeof (int) * nargs);
2708 for_each_template_parm (type,
2709 &mark_template_parm,
2713 if (tpd2.arg_uses_template_parms [i])
2715 /* The type depended on some template parameters.
2716 If they are fully specialized in the
2717 specialization, that's OK. */
2719 for (j = 0; j < nargs; ++j)
2720 if (tpd2.parms[j] != 0
2721 && tpd.arg_uses_template_parms [j])
2723 error ("type %qT of template argument %qE depends "
2724 "on template parameter(s)",
2734 if (retrieve_specialization (maintmpl, specargs,
2735 /*class_specializations_p=*/true))
2736 /* We've already got this specialization. */
2739 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2740 = tree_cons (inner_args, inner_parms,
2741 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2742 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2746 /* Check that a template declaration's use of default arguments is not
2747 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2748 nonzero if DECL is the thing declared by a primary template.
2749 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2752 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2755 int last_level_to_check;
2760 A default template-argument shall not be specified in a
2761 function template declaration or a function template definition, nor
2762 in the template-parameter-list of the definition of a member of a
2765 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2766 /* You can't have a function template declaration in a local
2767 scope, nor you can you define a member of a class template in a
2771 if (current_class_type
2772 && !TYPE_BEING_DEFINED (current_class_type)
2773 && DECL_LANG_SPECIFIC (decl)
2774 /* If this is either a friend defined in the scope of the class
2775 or a member function. */
2776 && (DECL_FUNCTION_MEMBER_P (decl)
2777 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2778 : DECL_FRIEND_CONTEXT (decl)
2779 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2781 /* And, if it was a member function, it really was defined in
2782 the scope of the class. */
2783 && (!DECL_FUNCTION_MEMBER_P (decl)
2784 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2785 /* We already checked these parameters when the template was
2786 declared, so there's no need to do it again now. This function
2787 was defined in class scope, but we're processing it's body now
2788 that the class is complete. */
2793 If a template-parameter has a default template-argument, all
2794 subsequent template-parameters shall have a default
2795 template-argument supplied. */
2796 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2798 tree inner_parms = TREE_VALUE (parm_level);
2799 int ntparms = TREE_VEC_LENGTH (inner_parms);
2800 int seen_def_arg_p = 0;
2803 for (i = 0; i < ntparms; ++i)
2805 tree parm = TREE_VEC_ELT (inner_parms, i);
2806 if (TREE_PURPOSE (parm))
2808 else if (seen_def_arg_p)
2810 error ("no default argument for %qD", TREE_VALUE (parm));
2811 /* For better subsequent error-recovery, we indicate that
2812 there should have been a default argument. */
2813 TREE_PURPOSE (parm) = error_mark_node;
2818 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2819 /* For an ordinary class template, default template arguments are
2820 allowed at the innermost level, e.g.:
2821 template <class T = int>
2823 but, in a partial specialization, they're not allowed even
2824 there, as we have in [temp.class.spec]:
2826 The template parameter list of a specialization shall not
2827 contain default template argument values.
2829 So, for a partial specialization, or for a function template,
2830 we look at all of them. */
2833 /* But, for a primary class template that is not a partial
2834 specialization we look at all template parameters except the
2836 parms = TREE_CHAIN (parms);
2838 /* Figure out what error message to issue. */
2839 if (TREE_CODE (decl) == FUNCTION_DECL)
2840 msg = "default template arguments may not be used in function templates";
2841 else if (is_partial)
2842 msg = "default template arguments may not be used in partial specializations";
2844 msg = "default argument for template parameter for class enclosing %qD";
2846 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2847 /* If we're inside a class definition, there's no need to
2848 examine the parameters to the class itself. On the one
2849 hand, they will be checked when the class is defined, and,
2850 on the other, default arguments are valid in things like:
2851 template <class T = double>
2852 struct S { template <class U> void f(U); };
2853 Here the default argument for `S' has no bearing on the
2854 declaration of `f'. */
2855 last_level_to_check = template_class_depth (current_class_type) + 1;
2857 /* Check everything. */
2858 last_level_to_check = 0;
2860 for (parm_level = parms;
2861 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2862 parm_level = TREE_CHAIN (parm_level))
2864 tree inner_parms = TREE_VALUE (parm_level);
2868 ntparms = TREE_VEC_LENGTH (inner_parms);
2869 for (i = 0; i < ntparms; ++i)
2870 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2878 /* Clear out the default argument so that we are not
2880 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2883 /* At this point, if we're still interested in issuing messages,
2884 they must apply to classes surrounding the object declared. */
2886 msg = "default argument for template parameter for class enclosing %qD";
2890 /* Worker for push_template_decl_real, called via
2891 for_each_template_parm. DATA is really an int, indicating the
2892 level of the parameters we are interested in. If T is a template
2893 parameter of that level, return nonzero. */
2896 template_parm_this_level_p (tree t, void* data)
2898 int this_level = *(int *)data;
2901 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2902 level = TEMPLATE_PARM_LEVEL (t);
2904 level = TEMPLATE_TYPE_LEVEL (t);
2905 return level == this_level;
2908 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2909 parameters given by current_template_args, or reuses a
2910 previously existing one, if appropriate. Returns the DECL, or an
2911 equivalent one, if it is replaced via a call to duplicate_decls.
2913 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2916 push_template_decl_real (tree decl, int is_friend)
2924 int new_template_p = 0;
2925 /* True if the template is a member template, in the sense of
2927 bool member_template_p = false;
2929 if (decl == error_mark_node)
2932 /* See if this is a partial specialization. */
2933 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2934 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2935 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2937 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2940 /* For a friend, we want the context of the friend function, not
2941 the type of which it is a friend. */
2942 ctx = DECL_CONTEXT (decl);
2943 else if (CP_DECL_CONTEXT (decl)
2944 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2945 /* In the case of a virtual function, we want the class in which
2947 ctx = CP_DECL_CONTEXT (decl);
2949 /* Otherwise, if we're currently defining some class, the DECL
2950 is assumed to be a member of the class. */
2951 ctx = current_scope ();
2953 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2956 if (!DECL_CONTEXT (decl))
2957 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2959 /* See if this is a primary template. */
2960 primary = template_parm_scope_p ();
2964 if (DECL_CLASS_SCOPE_P (decl))
2965 member_template_p = true;
2966 if (current_lang_name == lang_name_c)
2967 error ("template with C linkage");
2968 else if (TREE_CODE (decl) == TYPE_DECL
2969 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2970 error ("template class without a name");
2971 else if (TREE_CODE (decl) == FUNCTION_DECL)
2973 if (DECL_DESTRUCTOR_P (decl))
2977 A destructor shall not be a member template. */
2978 error ("destructor %qD declared as member template", decl);
2979 return error_mark_node;
2981 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2982 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2983 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2984 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2985 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2986 == void_list_node)))
2988 /* [basic.stc.dynamic.allocation]
2990 An allocation function can be a function
2991 template. ... Template allocation functions shall
2992 have two or more parameters. */
2993 error ("invalid template declaration of %qD", decl);
2997 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2998 && CLASS_TYPE_P (TREE_TYPE (decl)))
2999 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx)))
3003 error ("template declaration of %q#D", decl);
3004 return error_mark_node;
3008 /* Check to see that the rules regarding the use of default
3009 arguments are not being violated. */
3010 check_default_tmpl_args (decl, current_template_parms,
3011 primary, is_partial);
3014 return process_partial_specialization (decl);
3016 args = current_template_args ();
3019 || TREE_CODE (ctx) == FUNCTION_DECL
3020 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3021 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3023 if (DECL_LANG_SPECIFIC (decl)
3024 && DECL_TEMPLATE_INFO (decl)
3025 && DECL_TI_TEMPLATE (decl))
3026 tmpl = DECL_TI_TEMPLATE (decl);
3027 /* If DECL is a TYPE_DECL for a class-template, then there won't
3028 be DECL_LANG_SPECIFIC. The information equivalent to
3029 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3030 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3031 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3032 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3034 /* Since a template declaration already existed for this
3035 class-type, we must be redeclaring it here. Make sure
3036 that the redeclaration is valid. */
3037 redeclare_class_template (TREE_TYPE (decl),
3038 current_template_parms);
3039 /* We don't need to create a new TEMPLATE_DECL; just use the
3040 one we already had. */
3041 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3045 tmpl = build_template_decl (decl, current_template_parms,
3049 if (DECL_LANG_SPECIFIC (decl)
3050 && DECL_TEMPLATE_SPECIALIZATION (decl))
3052 /* A specialization of a member template of a template
3054 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3055 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3056 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3062 tree a, t, current, parms;
3065 if (TREE_CODE (decl) == TYPE_DECL)
3067 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3068 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3069 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3070 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3071 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3074 error ("%qD does not declare a template type", decl);
3078 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3080 error ("template definition of non-template %q#D", decl);
3084 tmpl = DECL_TI_TEMPLATE (decl);
3086 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3087 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3088 && DECL_TEMPLATE_SPECIALIZATION (decl)
3089 && DECL_MEMBER_TEMPLATE_P (tmpl))
3093 /* The declaration is a specialization of a member
3094 template, declared outside the class. Therefore, the
3095 innermost template arguments will be NULL, so we
3096 replace them with the arguments determined by the
3097 earlier call to check_explicit_specialization. */
3098 args = DECL_TI_ARGS (decl);
3101 = build_template_decl (decl, current_template_parms,
3103 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3104 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3105 DECL_TI_TEMPLATE (decl) = new_tmpl;
3106 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3107 DECL_TEMPLATE_INFO (new_tmpl)
3108 = tree_cons (tmpl, args, NULL_TREE);
3110 register_specialization (new_tmpl,
3111 most_general_template (tmpl),
3116 /* Make sure the template headers we got make sense. */
3118 parms = DECL_TEMPLATE_PARMS (tmpl);
3119 i = TMPL_PARMS_DEPTH (parms);
3120 if (TMPL_ARGS_DEPTH (args) != i)
3122 error ("expected %d levels of template parms for %q#D, got %d",
3123 i, decl, TMPL_ARGS_DEPTH (args));
3126 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3128 a = TMPL_ARGS_LEVEL (args, i);
3129 t = INNERMOST_TEMPLATE_PARMS (parms);
3131 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3133 if (current == decl)
3134 error ("got %d template parameters for %q#D",
3135 TREE_VEC_LENGTH (a), decl);
3137 error ("got %d template parameters for %q#T",
3138 TREE_VEC_LENGTH (a), current);
3139 error (" but %d required", TREE_VEC_LENGTH (t));
3142 /* Perhaps we should also check that the parms are used in the
3143 appropriate qualifying scopes in the declarator? */
3145 if (current == decl)
3148 current = TYPE_CONTEXT (current);
3152 DECL_TEMPLATE_RESULT (tmpl) = decl;
3153 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3155 /* Push template declarations for global functions and types. Note
3156 that we do not try to push a global template friend declared in a
3157 template class; such a thing may well depend on the template
3158 parameters of the class. */
3159 if (new_template_p && !ctx
3160 && !(is_friend && template_class_depth (current_class_type) > 0))
3162 tmpl = pushdecl_namespace_level (tmpl);
3163 if (tmpl == error_mark_node)
3164 return error_mark_node;
3169 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3170 if (DECL_CONV_FN_P (tmpl))
3172 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3174 /* It is a conversion operator. See if the type converted to
3175 depends on innermost template operands. */
3177 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3179 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3183 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3184 back to its most general template. If TMPL is a specialization,
3185 ARGS may only have the innermost set of arguments. Add the missing
3186 argument levels if necessary. */
3187 if (DECL_TEMPLATE_INFO (tmpl))
3188 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3190 info = tree_cons (tmpl, args, NULL_TREE);
3192 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3194 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3195 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3196 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3197 /* Don't change the name if we've already set it up. */
3198 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3199 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3201 else if (DECL_LANG_SPECIFIC (decl))
3202 DECL_TEMPLATE_INFO (decl) = info;
3204 return DECL_TEMPLATE_RESULT (tmpl);
3208 push_template_decl (tree decl)
3210 return push_template_decl_real (decl, 0);
3213 /* Called when a class template TYPE is redeclared with the indicated
3214 template PARMS, e.g.:
3216 template <class T> struct S;
3217 template <class T> struct S {}; */
3220 redeclare_class_template (tree type, tree parms)
3226 if (!TYPE_TEMPLATE_INFO (type))
3228 error ("%qT is not a template type", type);
3232 tmpl = TYPE_TI_TEMPLATE (type);
3233 if (!PRIMARY_TEMPLATE_P (tmpl))
3234 /* The type is nested in some template class. Nothing to worry
3235 about here; there are no new template parameters for the nested
3239 parms = INNERMOST_TEMPLATE_PARMS (parms);
3240 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3242 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3244 cp_error_at ("previous declaration %qD", tmpl);
3245 error ("used %d template parameter%s instead of %d",
3246 TREE_VEC_LENGTH (tmpl_parms),
3247 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
3248 TREE_VEC_LENGTH (parms));
3252 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3254 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3255 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3256 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3257 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3259 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3261 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3262 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3263 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3265 cp_error_at ("template parameter %q#D", tmpl_parm);
3266 error ("redeclared here as %q#D", parm);
3270 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3272 /* We have in [temp.param]:
3274 A template-parameter may not be given default arguments
3275 by two different declarations in the same scope. */
3276 error ("redefinition of default argument for %q#D", parm);
3277 error ("%J original definition appeared here", tmpl_parm);
3281 if (parm_default != NULL_TREE)
3282 /* Update the previous template parameters (which are the ones
3283 that will really count) with the new default value. */
3284 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3285 else if (tmpl_default != NULL_TREE)
3286 /* Update the new parameters, too; they'll be used as the
3287 parameters for any members. */
3288 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3292 /* Simplify EXPR if it is a non-dependent expression. Returns the
3293 (possibly simplified) expression. */
3296 fold_non_dependent_expr (tree expr)
3298 /* If we're in a template, but EXPR isn't value dependent, simplify
3299 it. We're supposed to treat:
3301 template <typename T> void f(T[1 + 1]);
3302 template <typename T> void f(T[2]);
3304 as two declarations of the same function, for example. */
3305 if (processing_template_decl
3306 && !type_dependent_expression_p (expr)
3307 && !value_dependent_expression_p (expr))
3309 HOST_WIDE_INT saved_processing_template_decl;
3311 saved_processing_template_decl = processing_template_decl;
3312 processing_template_decl = 0;
3313 expr = tsubst_copy_and_build (expr,
3316 /*in_decl=*/NULL_TREE,
3317 /*function_p=*/false);
3318 processing_template_decl = saved_processing_template_decl;
3323 /* EXPR is an expression which is used in a constant-expression context.
3324 For instance, it could be a VAR_DECL with a constant initializer.
3325 Extract the innest constant expression.
3327 This is basically a more powerful version of
3328 integral_constant_value, which can be used also in templates where
3329 initializers can maintain a syntactic rather than semantic form
3330 (even if they are non-dependent, for access-checking purposes). */
3333 fold_decl_constant_value (tree expr)
3335 tree const_expr = expr;
3338 expr = fold_non_dependent_expr (const_expr);
3339 const_expr = integral_constant_value (expr);
3341 while (expr != const_expr);
3346 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3347 must be a function or a pointer-to-function type, as specified
3348 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3349 and check that the resulting function has external linkage. */
3352 convert_nontype_argument_function (tree type, tree expr)
3357 fn = instantiate_type (type, fns, tf_none);
3358 if (fn == error_mark_node)
3359 return error_mark_node;
3362 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3363 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3365 /* [temp.arg.nontype]/1
3367 A template-argument for a non-type, non-template template-parameter
3370 -- the address of an object or function with external linkage. */
3371 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3373 error ("%qE is not a valid template argument for type %qT "
3374 "because function %qD has not external linkage",
3375 expr, type, fn_no_ptr);
3382 /* Attempt to convert the non-type template parameter EXPR to the
3383 indicated TYPE. If the conversion is successful, return the
3384 converted value. If the conversion is unsuccessful, return
3385 NULL_TREE if we issued an error message, or error_mark_node if we
3386 did not. We issue error messages for out-and-out bad template
3387 parameters, but not simply because the conversion failed, since we
3388 might be just trying to do argument deduction. Both TYPE and EXPR
3389 must be non-dependent.
3391 The conversion follows the special rules described in
3392 [temp.arg.nontype], and it is much more strict than an implicit
3395 This function is called twice for each template argument (see
3396 lookup_template_class for a more accurate description of this
3397 problem). This means that we need to handle expressions which
3398 are not valid in a C++ source, but can be created from the
3399 first call (for instance, casts to perform conversions). These
3400 hacks can go away after we fix the double coercion problem. */
3403 convert_nontype_argument (tree type, tree expr)
3407 /* Detect immediately string literals as invalid non-type argument.
3408 This special-case is not needed for correctness (we would easily
3409 catch this later), but only to provide better diagnostic for this
3410 common user mistake. As suggested by DR 100, we do not mention
3411 linkage issues in the diagnostic as this is not the point. */
3412 if (TREE_CODE (expr) == STRING_CST)
3414 error ("%qE is not a valid template argument for type %qT "
3415 "because string literals can never be used in this context",
3420 /* If we are in a template, EXPR may be non-dependent, but still
3421 have a syntactic, rather than semantic, form. For example, EXPR
3422 might be a SCOPE_REF, rather than the VAR_DECL to which the
3423 SCOPE_REF refers. Preserving the qualifying scope is necessary
3424 so that access checking can be performed when the template is
3425 instantiated -- but here we need the resolved form so that we can
3426 convert the argument. */
3427 expr = fold_non_dependent_expr (expr);
3428 expr_type = TREE_TYPE (expr);
3430 /* HACK: Due to double coercion, we can get a
3431 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3432 which is the tree that we built on the first call (see
3433 below when coercing to reference to object or to reference to
3434 function). We just strip everything and get to the arg.
3435 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3437 if (TREE_CODE (expr) == NOP_EXPR)
3439 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3441 /* ??? Maybe we could use convert_from_reference here, but we
3442 would need to relax its constraints because the NOP_EXPR
3443 could actually change the type to something more cv-qualified,
3444 and this is not folded by convert_from_reference. */
3445 tree addr = TREE_OPERAND (expr, 0);
3446 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3447 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3448 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3449 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3450 (TREE_TYPE (expr_type),
3451 TREE_TYPE (TREE_TYPE (addr))));
3453 expr = TREE_OPERAND (addr, 0);
3454 expr_type = TREE_TYPE (expr);
3457 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3458 parameter is a pointer to object, through decay and
3459 qualification conversion. Let's strip everything. */
3460 else if (TYPE_PTROBV_P (type))
3463 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3464 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3465 /* Skip the ADDR_EXPR only if it is part of the decay for
3466 an array. Otherwise, it is part of the original argument
3467 in the source code. */
3468 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3469 expr = TREE_OPERAND (expr, 0);
3470 expr_type = TREE_TYPE (expr);
3474 /* [temp.arg.nontype]/5, bullet 1
3476 For a non-type template-parameter of integral or enumeration type,
3477 integral promotions (_conv.prom_) and integral conversions
3478 (_conv.integral_) are applied. */
3479 if (INTEGRAL_TYPE_P (type))
3481 if (!INTEGRAL_TYPE_P (expr_type))
3482 return error_mark_node;
3484 expr = fold_decl_constant_value (expr);
3485 /* Notice that there are constant expressions like '4 % 0' which
3486 do not fold into integer constants. */
3487 if (TREE_CODE (expr) != INTEGER_CST)
3489 error ("%qE is not a valid template argument for type %qT "
3490 "because it is a non-constant expression", expr, type);
3494 /* At this point, an implicit conversion does what we want,
3495 because we already know that the expression is of integral
3497 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3498 if (expr == error_mark_node)
3499 return error_mark_node;
3501 /* Conversion was allowed: fold it to a bare integer constant. */
3504 /* [temp.arg.nontype]/5, bullet 2
3506 For a non-type template-parameter of type pointer to object,
3507 qualification conversions (_conv.qual_) and the array-to-pointer
3508 conversion (_conv.array_) are applied. */
3509 else if (TYPE_PTROBV_P (type))
3511 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3513 A template-argument for a non-type, non-template template-parameter
3514 shall be one of: [...]
3516 -- the name of a non-type template-parameter;
3517 -- the address of an object or function with external linkage, [...]
3518 expressed as "& id-expression" where the & is optional if the name
3519 refers to a function or array, or if the corresponding
3520 template-parameter is a reference.
3522 Here, we do not care about functions, as they are invalid anyway
3523 for a parameter of type pointer-to-object. */
3524 bool constant_address_p =
3525 (TREE_CODE (expr) == ADDR_EXPR
3526 || TREE_CODE (expr_type) == ARRAY_TYPE
3527 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3529 expr = decay_conversion (expr);
3530 if (expr == error_mark_node)
3531 return error_mark_node;
3533 expr = perform_qualification_conversions (type, expr);
3534 if (expr == error_mark_node)
3535 return error_mark_node;
3537 if (!constant_address_p)
3539 error ("%qE is not a valid template argument for type %qT "
3540 "because it is not a constant pointer", expr, type);
3544 /* [temp.arg.nontype]/5, bullet 3
3546 For a non-type template-parameter of type reference to object, no
3547 conversions apply. The type referred to by the reference may be more
3548 cv-qualified than the (otherwise identical) type of the
3549 template-argument. The template-parameter is bound directly to the
3550 template-argument, which must be an lvalue. */
3551 else if (TYPE_REF_OBJ_P (type))
3553 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3555 return error_mark_node;
3557 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3559 error ("%qE is not a valid template argument for type %qT "
3560 "because of conflicts in cv-qualification", expr, type);
3564 if (!real_lvalue_p (expr))
3566 error ("%qE is not a valid template argument for type %qT "
3567 "because it is not a lvalue", expr, type);
3571 /* [temp.arg.nontype]/1
3573 A template-argument for a non-type, non-template template-parameter
3574 shall be one of: [...]
3576 -- the address of an object or function with external linkage. */
3577 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3579 error ("%qE is not a valid template argument for type %qT "
3580 "because object %qD has not external linkage",
3585 expr = build_nop (type, build_address (expr));
3587 /* [temp.arg.nontype]/5, bullet 4
3589 For a non-type template-parameter of type pointer to function, only
3590 the function-to-pointer conversion (_conv.func_) is applied. If the
3591 template-argument represents a set of overloaded functions (or a
3592 pointer to such), the matching function is selected from the set
3594 else if (TYPE_PTRFN_P (type))
3596 /* If the argument is a template-id, we might not have enough
3597 context information to decay the pointer.
3598 ??? Why static5.C requires decay and subst1.C works fine
3600 if (!type_unknown_p (expr_type))
3602 expr = decay_conversion (expr);
3603 if (expr == error_mark_node)
3604 return error_mark_node;
3607 expr = convert_nontype_argument_function (type, expr);
3608 if (!expr || expr == error_mark_node)
3611 /* [temp.arg.nontype]/5, bullet 5
3613 For a non-type template-parameter of type reference to function, no
3614 conversions apply. If the template-argument represents a set of
3615 overloaded functions, the matching function is selected from the set
3617 else if (TYPE_REFFN_P (type))
3619 if (TREE_CODE (expr) == ADDR_EXPR)
3621 error ("%qE is not a valid template argument for type %qT "
3622 "because it is a pointer", expr, type);
3623 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3627 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3628 if (!expr || expr == error_mark_node)
3631 expr = build_nop(type, build_address (expr));
3633 /* [temp.arg.nontype]/5, bullet 6
3635 For a non-type template-parameter of type pointer to member function,
3636 no conversions apply. If the template-argument represents a set of
3637 overloaded member functions, the matching member function is selected
3638 from the set (_over.over_). */
3639 else if (TYPE_PTRMEMFUNC_P (type))
3641 expr = instantiate_type (type, expr, tf_none);
3642 if (expr == error_mark_node)
3643 return error_mark_node;
3645 /* There is no way to disable standard conversions in
3646 resolve_address_of_overloaded_function (called by
3647 instantiate_type). It is possible that the call succeeded by
3648 converting &B::I to &D::I (where B is a base of D), so we need
3649 to reject this conversion here.
3651 Actually, even if there was a way to disable standard conversions,
3652 it would still be better to reject them here so that we can
3653 provide a superior diagnostic. */
3654 if (!same_type_p (TREE_TYPE (expr), type))
3656 /* Make sure we are just one standard conversion off. */
3657 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3658 error ("%qE is not a valid template argument for type %qT "
3659 "because it is of type %qT", expr, type,
3661 inform ("standard conversions are not allowed in this context");
3665 /* [temp.arg.nontype]/5, bullet 7
3667 For a non-type template-parameter of type pointer to data member,
3668 qualification conversions (_conv.qual_) are applied. */
3669 else if (TYPE_PTRMEM_P (type))
3671 expr = perform_qualification_conversions (type, expr);
3672 if (expr == error_mark_node)
3675 /* A template non-type parameter must be one of the above. */
3679 /* Sanity check: did we actually convert the argument to the
3681 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3686 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3687 template template parameters. Both PARM_PARMS and ARG_PARMS are
3688 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3691 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3692 the case, then extra parameters must have default arguments.
3694 Consider the example:
3695 template <class T, class Allocator = allocator> class vector;
3696 template<template <class U> class TT> class C;
3698 C<vector> is a valid instantiation. PARM_PARMS for the above code
3699 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3700 T and Allocator) and OUTER_ARGS contains the argument that is used to
3701 substitute the TT parameter. */
3704 coerce_template_template_parms (tree parm_parms,
3706 tsubst_flags_t complain,
3710 int nparms, nargs, i;
3713 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3714 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3716 nparms = TREE_VEC_LENGTH (parm_parms);
3717 nargs = TREE_VEC_LENGTH (arg_parms);
3719 /* The rule here is opposite of coerce_template_parms. */
3722 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3725 for (i = 0; i < nparms; ++i)
3727 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3728 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3730 if (arg == NULL_TREE || arg == error_mark_node
3731 || parm == NULL_TREE || parm == error_mark_node)
3734 if (TREE_CODE (arg) != TREE_CODE (parm))
3737 switch (TREE_CODE (parm))
3743 /* We encounter instantiations of templates like
3744 template <template <template <class> class> class TT>
3747 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3748 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3750 if (!coerce_template_template_parms
3751 (parmparm, argparm, complain, in_decl, outer_args))
3757 /* The tsubst call is used to handle cases such as
3759 template <int> class C {};
3760 template <class T, template <T> class TT> class D {};
3763 i.e. the parameter list of TT depends on earlier parameters. */
3764 if (!dependent_type_p (TREE_TYPE (arg))
3766 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3778 /* Convert the indicated template ARG as necessary to match the
3779 indicated template PARM. Returns the converted ARG, or
3780 error_mark_node if the conversion was unsuccessful. Error and
3781 warning messages are issued under control of COMPLAIN. This
3782 conversion is for the Ith parameter in the parameter list. ARGS is
3783 the full set of template arguments deduced so far. */
3786 convert_template_argument (tree parm,
3789 tsubst_flags_t complain,
3795 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3797 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3799 if (TREE_CODE (arg) == TREE_LIST
3800 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3802 /* The template argument was the name of some
3803 member function. That's usually
3804 invalid, but static members are OK. In any
3805 case, grab the underlying fields/functions
3806 and issue an error later if required. */
3807 arg = TREE_VALUE (arg);
3808 TREE_TYPE (arg) = unknown_type_node;
3811 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3812 requires_type = (TREE_CODE (parm) == TYPE_DECL
3813 || requires_tmpl_type);
3815 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3816 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3817 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3818 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3821 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3822 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3823 arg = TYPE_STUB_DECL (arg);
3825 is_type = TYPE_P (arg) || is_tmpl_type;
3827 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3828 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3830 pedwarn ("to refer to a type member of a template parameter, "
3831 "use %<typename %E%>", arg);
3833 arg = make_typename_type (TREE_OPERAND (arg, 0),
3834 TREE_OPERAND (arg, 1),
3836 complain & tf_error);
3839 if (is_type != requires_type)
3843 if (complain & tf_error)
3845 error ("type/value mismatch at argument %d in template "
3846 "parameter list for %qD",
3849 error (" expected a constant of type %qT, got %qT",
3851 (is_tmpl_type ? DECL_NAME (arg) : arg));
3852 else if (requires_tmpl_type)
3853 error (" expected a class template, got %qE", arg);
3855 error (" expected a type, got %qE", arg);
3858 return error_mark_node;
3860 if (is_tmpl_type ^ requires_tmpl_type)
3862 if (in_decl && (complain & tf_error))
3864 error ("type/value mismatch at argument %d in template "
3865 "parameter list for %qD",
3868 error (" expected a type, got %qT", DECL_NAME (arg));
3870 error (" expected a class template, got %qT", arg);
3872 return error_mark_node;
3877 if (requires_tmpl_type)
3879 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3880 /* The number of argument required is not known yet.
3881 Just accept it for now. */
3882 val = TREE_TYPE (arg);
3885 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3886 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3888 if (coerce_template_template_parms (parmparm, argparm,
3894 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3896 if (val != error_mark_node
3897 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3898 val = TREE_TYPE (val);
3902 if (in_decl && (complain & tf_error))
3904 error ("type/value mismatch at argument %d in "
3905 "template parameter list for %qD",
3907 error (" expected a template of type %qD, got %qD",
3911 val = error_mark_node;
3920 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3922 if (invalid_nontype_parm_type_p (t, complain))
3923 return error_mark_node;
3925 if (!uses_template_parms (arg) && !uses_template_parms (t))
3926 /* We used to call digest_init here. However, digest_init
3927 will report errors, which we don't want when complain
3928 is zero. More importantly, digest_init will try too
3929 hard to convert things: for example, `0' should not be
3930 converted to pointer type at this point according to
3931 the standard. Accepting this is not merely an
3932 extension, since deciding whether or not these
3933 conversions can occur is part of determining which
3934 function template to call, or whether a given explicit
3935 argument specification is valid. */
3936 val = convert_nontype_argument (t, arg);
3940 if (val == NULL_TREE)
3941 val = error_mark_node;
3942 else if (val == error_mark_node && (complain & tf_error))
3943 error ("could not convert template argument %qE to %qT", arg, t);
3949 /* Convert all template arguments to their appropriate types, and
3950 return a vector containing the innermost resulting template
3951 arguments. If any error occurs, return error_mark_node. Error and
3952 warning messages are issued under control of COMPLAIN.
3954 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3955 provided in ARGLIST, or else trailing parameters must have default
3956 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3957 deduction for any unspecified trailing arguments. */
3960 coerce_template_parms (tree parms,
3963 tsubst_flags_t complain,
3964 int require_all_arguments)
3966 int nparms, nargs, i, lost = 0;
3969 tree new_inner_args;
3971 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3972 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3973 nparms = TREE_VEC_LENGTH (parms);
3977 && require_all_arguments
3978 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3980 if (complain & tf_error)
3982 error ("wrong number of template arguments (%d, should be %d)",
3986 cp_error_at ("provided for %qD", in_decl);
3989 return error_mark_node;
3992 new_inner_args = make_tree_vec (nparms);
3993 new_args = add_outermost_template_args (args, new_inner_args);
3994 for (i = 0; i < nparms; i++)
3999 /* Get the Ith template parameter. */
4000 parm = TREE_VEC_ELT (parms, i);
4002 /* Calculate the Ith argument. */
4004 arg = TREE_VEC_ELT (inner_args, i);
4005 else if (require_all_arguments)
4006 /* There must be a default arg in this case. */
4007 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4013 if (arg == error_mark_node)
4015 if (complain & tf_error)
4016 error ("template argument %d is invalid", i + 1);
4019 arg = convert_template_argument (TREE_VALUE (parm),
4020 arg, new_args, complain, i,
4023 if (arg == error_mark_node)
4025 TREE_VEC_ELT (new_inner_args, i) = arg;
4029 return error_mark_node;
4031 return new_inner_args;
4034 /* Returns 1 if template args OT and NT are equivalent. */
4037 template_args_equal (tree ot, tree nt)
4042 if (TREE_CODE (nt) == TREE_VEC)
4043 /* For member templates */
4044 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4045 else if (TYPE_P (nt))
4046 return TYPE_P (ot) && same_type_p (ot, nt);
4047 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4050 return cp_tree_equal (ot, nt);
4053 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4054 of template arguments. Returns 0 otherwise. */
4057 comp_template_args (tree oldargs, tree newargs)
4061 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4064 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4066 tree nt = TREE_VEC_ELT (newargs, i);
4067 tree ot = TREE_VEC_ELT (oldargs, i);
4069 if (! template_args_equal (ot, nt))
4075 /* Given class template name and parameter list, produce a user-friendly name
4076 for the instantiation. */
4079 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4081 static struct obstack scratch_obstack;
4082 static char *scratch_firstobj;
4085 if (!scratch_firstobj)
4086 gcc_obstack_init (&scratch_obstack);
4088 obstack_free (&scratch_obstack, scratch_firstobj);
4089 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4091 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4092 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4096 nparms = TREE_VEC_LENGTH (parms);
4097 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4098 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4099 for (i = 0; i < nparms; i++)
4101 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4102 tree arg = TREE_VEC_ELT (arglist, i);
4107 if (TREE_CODE (parm) == TYPE_DECL)
4109 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4112 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4114 if (TREE_CODE (arg) == TEMPLATE_DECL)
4116 /* Already substituted with real template. Just output
4117 the template name here */
4118 tree context = DECL_CONTEXT (arg);
4121 /* The template may be defined in a namespace, or
4122 may be a member template. */
4123 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4124 || CLASS_TYPE_P (context));
4125 cat (decl_as_string (DECL_CONTEXT (arg),
4126 TFF_PLAIN_IDENTIFIER));
4129 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4132 /* Output the parameter declaration. */
4133 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4137 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4139 /* No need to check arglist against parmlist here; we did that
4140 in coerce_template_parms, called from lookup_template_class. */
4141 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4144 char *bufp = obstack_next_free (&scratch_obstack);
4146 while (bufp[offset - 1] == ' ')
4148 obstack_blank_fast (&scratch_obstack, offset);
4150 /* B<C<char> >, not B<C<char>> */
4151 if (bufp[offset - 1] == '>')
4156 return (char *) obstack_base (&scratch_obstack);
4160 classtype_mangled_name (tree t)
4162 if (CLASSTYPE_TEMPLATE_INFO (t)
4163 /* Specializations have already had their names set up in
4164 lookup_template_class. */
4165 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4167 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4169 /* For non-primary templates, the template parameters are
4170 implicit from their surrounding context. */
4171 if (PRIMARY_TEMPLATE_P (tmpl))
4173 tree name = DECL_NAME (tmpl);
4174 char *mangled_name = mangle_class_name_for_template
4175 (IDENTIFIER_POINTER (name),
4176 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4177 CLASSTYPE_TI_ARGS (t));
4178 tree id = get_identifier (mangled_name);
4179 IDENTIFIER_TEMPLATE (id) = name;
4184 return TYPE_IDENTIFIER (t);
4188 add_pending_template (tree d)
4190 tree ti = (TYPE_P (d)
4191 ? CLASSTYPE_TEMPLATE_INFO (d)
4192 : DECL_TEMPLATE_INFO (d));
4196 if (TI_PENDING_TEMPLATE_FLAG (ti))
4199 /* We are called both from instantiate_decl, where we've already had a
4200 tinst_level pushed, and instantiate_template, where we haven't.
4202 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4205 push_tinst_level (d);
4207 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4208 if (last_pending_template)
4209 TREE_CHAIN (last_pending_template) = pt;
4211 pending_templates = pt;
4213 last_pending_template = pt;
4215 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4222 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4223 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4224 documentation for TEMPLATE_ID_EXPR. */
4227 lookup_template_function (tree fns, tree arglist)
4231 if (fns == error_mark_node || arglist == error_mark_node)
4232 return error_mark_node;
4234 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4235 if (fns == NULL_TREE
4236 || TREE_CODE (fns) == FUNCTION_DECL)
4238 error ("non-template used as template");
4239 return error_mark_node;
4242 gcc_assert (TREE_CODE (fns) == TEMPLATE_DECL
4243 || TREE_CODE (fns) == OVERLOAD
4245 || TREE_CODE (fns) == IDENTIFIER_NODE);
4247 if (BASELINK_P (fns))
4249 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4251 BASELINK_FUNCTIONS (fns),
4256 type = TREE_TYPE (fns);
4257 if (TREE_CODE (fns) == OVERLOAD || !type)
4258 type = unknown_type_node;
4260 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4263 /* Within the scope of a template class S<T>, the name S gets bound
4264 (in build_self_reference) to a TYPE_DECL for the class, not a
4265 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4266 or one of its enclosing classes, and that type is a template,
4267 return the associated TEMPLATE_DECL. Otherwise, the original
4268 DECL is returned. */
4271 maybe_get_template_decl_from_type_decl (tree decl)
4273 return (decl != NULL_TREE
4274 && TREE_CODE (decl) == TYPE_DECL
4275 && DECL_ARTIFICIAL (decl)
4276 && CLASS_TYPE_P (TREE_TYPE (decl))
4277 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4278 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4281 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4282 parameters, find the desired type.
4284 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4286 IN_DECL, if non-NULL, is the template declaration we are trying to
4289 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4290 the class we are looking up.
4292 Issue error and warning messages under control of COMPLAIN.
4294 If the template class is really a local class in a template
4295 function, then the FUNCTION_CONTEXT is the function in which it is
4298 ??? Note that this function is currently called *twice* for each
4299 template-id: the first time from the parser, while creating the
4300 incomplete type (finish_template_type), and the second type during the
4301 real instantiation (instantiate_template_class). This is surely something
4302 that we want to avoid. It also causes some problems with argument
4303 coercion (see convert_nontype_argument for more information on this). */
4306 lookup_template_class (tree d1,
4311 tsubst_flags_t complain)
4313 tree template = NULL_TREE, parmlist;
4316 timevar_push (TV_NAME_LOOKUP);
4318 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4320 tree value = innermost_non_namespace_value (d1);
4321 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4326 push_decl_namespace (context);
4327 template = lookup_name (d1, /*prefer_type=*/0);
4328 template = maybe_get_template_decl_from_type_decl (template);
4330 pop_decl_namespace ();
4333 context = DECL_CONTEXT (template);
4335 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4337 tree type = TREE_TYPE (d1);
4339 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4340 an implicit typename for the second A. Deal with it. */
4341 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4342 type = TREE_TYPE (type);
4344 if (CLASSTYPE_TEMPLATE_INFO (type))
4346 template = CLASSTYPE_TI_TEMPLATE (type);
4347 d1 = DECL_NAME (template);
4350 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4351 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4353 template = TYPE_TI_TEMPLATE (d1);
4354 d1 = DECL_NAME (template);
4356 else if (TREE_CODE (d1) == TEMPLATE_DECL
4357 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4360 d1 = DECL_NAME (template);
4361 context = DECL_CONTEXT (template);
4364 /* Issue an error message if we didn't find a template. */
4367 if (complain & tf_error)
4368 error ("%qT is not a template", d1);
4369 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4372 if (TREE_CODE (template) != TEMPLATE_DECL
4373 /* Make sure it's a user visible template, if it was named by
4375 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4376 && !PRIMARY_TEMPLATE_P (template)))
4378 if (complain & tf_error)
4380 error ("non-template type %qT used as a template", d1);
4382 cp_error_at ("for template declaration %qD", in_decl);
4384 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4387 complain &= ~tf_user;
4389 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4391 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4392 template arguments */
4397 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4399 /* Consider an example where a template template parameter declared as
4401 template <class T, class U = std::allocator<T> > class TT
4403 The template parameter level of T and U are one level larger than
4404 of TT. To proper process the default argument of U, say when an
4405 instantiation `TT<int>' is seen, we need to build the full
4406 arguments containing {int} as the innermost level. Outer levels,
4407 available when not appearing as default template argument, can be
4408 obtained from `current_template_args ()'.
4410 Suppose that TT is later substituted with std::vector. The above
4411 instantiation is `TT<int, std::allocator<T> >' with TT at
4412 level 1, and T at level 2, while the template arguments at level 1
4413 becomes {std::vector} and the inner level 2 is {int}. */
4415 if (current_template_parms)
4416 arglist = add_to_template_args (current_template_args (), arglist);
4418 arglist2 = coerce_template_parms (parmlist, arglist, template,
4419 complain, /*require_all_args=*/1);
4420 if (arglist2 == error_mark_node
4421 || (!uses_template_parms (arglist2)
4422 && check_instantiated_args (template, arglist2, complain)))
4423 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4425 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4426 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4430 tree template_type = TREE_TYPE (template);
4433 tree found = NULL_TREE;
4436 int is_partial_instantiation;
4438 gen_tmpl = most_general_template (template);
4439 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4440 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4441 arg_depth = TMPL_ARGS_DEPTH (arglist);
4443 if (arg_depth == 1 && parm_depth > 1)
4445 /* We've been given an incomplete set of template arguments.
4448 template <class T> struct S1 {
4449 template <class U> struct S2 {};
4450 template <class U> struct S2<U*> {};
4453 we will be called with an ARGLIST of `U*', but the
4454 TEMPLATE will be `template <class T> template
4455 <class U> struct S1<T>::S2'. We must fill in the missing
4458 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4460 arg_depth = TMPL_ARGS_DEPTH (arglist);
4463 /* Now we should have enough arguments. */
4464 gcc_assert (parm_depth == arg_depth);
4466 /* From here on, we're only interested in the most general
4468 template = gen_tmpl;
4470 /* Calculate the BOUND_ARGS. These will be the args that are
4471 actually tsubst'd into the definition to create the
4475 /* We have multiple levels of arguments to coerce, at once. */
4477 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4479 tree bound_args = make_tree_vec (parm_depth);
4481 for (i = saved_depth,
4482 t = DECL_TEMPLATE_PARMS (template);
4483 i > 0 && t != NULL_TREE;
4484 --i, t = TREE_CHAIN (t))
4486 tree a = coerce_template_parms (TREE_VALUE (t),
4488 complain, /*require_all_args=*/1);
4490 /* Don't process further if one of the levels fails. */
4491 if (a == error_mark_node)
4493 /* Restore the ARGLIST to its full size. */
4494 TREE_VEC_LENGTH (arglist) = saved_depth;
4495 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4498 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4500 /* We temporarily reduce the length of the ARGLIST so
4501 that coerce_template_parms will see only the arguments
4502 corresponding to the template parameters it is
4504 TREE_VEC_LENGTH (arglist)--;
4507 /* Restore the ARGLIST to its full size. */
4508 TREE_VEC_LENGTH (arglist) = saved_depth;
4510 arglist = bound_args;
4514 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4515 INNERMOST_TEMPLATE_ARGS (arglist),
4517 complain, /*require_all_args=*/1);
4519 if (arglist == error_mark_node)
4520 /* We were unable to bind the arguments. */
4521 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4523 /* In the scope of a template class, explicit references to the
4524 template class refer to the type of the template, not any
4525 instantiation of it. For example, in:
4527 template <class T> class C { void f(C<T>); }
4529 the `C<T>' is just the same as `C'. Outside of the
4530 class, however, such a reference is an instantiation. */
4531 if (comp_template_args (TYPE_TI_ARGS (template_type),
4534 found = template_type;
4536 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4540 for (ctx = current_class_type;
4541 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4543 ? TYPE_CONTEXT (ctx)
4544 : DECL_CONTEXT (ctx)))
4545 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4548 /* We're not in the scope of the class, so the
4549 TEMPLATE_TYPE is not the type we want after all. */
4555 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4557 /* If we already have this specialization, return it. */
4558 found = retrieve_specialization (template, arglist,
4559 /*class_specializations_p=*/false);
4561 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4563 /* This type is a "partial instantiation" if any of the template
4564 arguments still involve template parameters. Note that we set
4565 IS_PARTIAL_INSTANTIATION for partial specializations as
4567 is_partial_instantiation = uses_template_parms (arglist);
4569 /* If the deduced arguments are invalid, then the binding
4571 if (!is_partial_instantiation
4572 && check_instantiated_args (template,
4573 INNERMOST_TEMPLATE_ARGS (arglist),
4575 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4577 if (!is_partial_instantiation
4578 && !PRIMARY_TEMPLATE_P (template)
4579 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4581 found = xref_tag_from_type (TREE_TYPE (template),
4582 DECL_NAME (template),
4583 /*tag_scope=*/ts_global);
4584 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4587 context = tsubst (DECL_CONTEXT (template), arglist,
4590 context = global_namespace;
4592 /* Create the type. */
4593 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4595 if (!is_partial_instantiation)
4597 set_current_access_from_decl (TYPE_NAME (template_type));
4598 t = start_enum (TYPE_IDENTIFIER (template_type));
4601 /* We don't want to call start_enum for this type, since
4602 the values for the enumeration constants may involve
4603 template parameters. And, no one should be interested
4604 in the enumeration constants for such a type. */
4605 t = make_node (ENUMERAL_TYPE);
4609 t = make_aggr_type (TREE_CODE (template_type));
4610 CLASSTYPE_DECLARED_CLASS (t)
4611 = CLASSTYPE_DECLARED_CLASS (template_type);
4612 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4613 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4615 /* A local class. Make sure the decl gets registered properly. */
4616 if (context == current_function_decl)
4617 pushtag (DECL_NAME (template), t, 0);
4620 /* If we called start_enum or pushtag above, this information
4621 will already be set up. */
4624 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4626 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4627 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4628 TYPE_STUB_DECL (t) = type_decl;
4629 DECL_SOURCE_LOCATION (type_decl)
4630 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4633 type_decl = TYPE_NAME (t);
4635 TREE_PRIVATE (type_decl)
4636 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4637 TREE_PROTECTED (type_decl)
4638 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4640 /* Set up the template information. We have to figure out which
4641 template is the immediate parent if this is a full
4643 if (parm_depth == 1 || is_partial_instantiation
4644 || !PRIMARY_TEMPLATE_P (template))
4645 /* This case is easy; there are no member templates involved. */
4649 /* This is a full instantiation of a member template. Look
4650 for a partial instantiation of which this is an instance. */
4652 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4653 found; found = TREE_CHAIN (found))
4656 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4658 /* We only want partial instantiations, here, not
4659 specializations or full instantiations. */
4660 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4661 || !uses_template_parms (TREE_VALUE (found)))
4664 /* Temporarily reduce by one the number of levels in the
4665 ARGLIST and in FOUND so as to avoid comparing the
4666 last set of arguments. */
4667 TREE_VEC_LENGTH (arglist)--;
4668 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4670 /* See if the arguments match. If they do, then TMPL is
4671 the partial instantiation we want. */
4672 success = comp_template_args (TREE_PURPOSE (found), arglist);
4674 /* Restore the argument vectors to their full size. */
4675 TREE_VEC_LENGTH (arglist)++;
4676 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4687 /* There was no partial instantiation. This happens
4688 where C<T> is a member template of A<T> and it's used
4691 template <typename T> struct B { A<T>::C<int> m; };
4694 Create the partial instantiation.
4696 TREE_VEC_LENGTH (arglist)--;
4697 found = tsubst (template, arglist, complain, NULL_TREE);
4698 TREE_VEC_LENGTH (arglist)++;
4702 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4703 DECL_TEMPLATE_INSTANTIATIONS (template)
4704 = tree_cons (arglist, t,
4705 DECL_TEMPLATE_INSTANTIATIONS (template));
4707 if (TREE_CODE (t) == ENUMERAL_TYPE
4708 && !is_partial_instantiation)
4709 /* Now that the type has been registered on the instantiations
4710 list, we set up the enumerators. Because the enumeration
4711 constants may involve the enumeration type itself, we make
4712 sure to register the type first, and then create the
4713 constants. That way, doing tsubst_expr for the enumeration
4714 constants won't result in recursive calls here; we'll find
4715 the instantiation and exit above. */
4716 tsubst_enum (template_type, t, arglist);
4718 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4720 if (TREE_CODE (t) != ENUMERAL_TYPE)
4721 DECL_NAME (type_decl) = classtype_mangled_name (t);
4722 if (is_partial_instantiation)
4723 /* If the type makes use of template parameters, the
4724 code that generates debugging information will crash. */
4725 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4727 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4729 timevar_pop (TV_NAME_LOOKUP);
4736 struct pointer_set_t *visited;
4739 /* Called from for_each_template_parm via walk_tree. */
4742 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4745 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4746 tree_fn_t fn = pfd->fn;
4747 void *data = pfd->data;
4750 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4751 return error_mark_node;
4753 switch (TREE_CODE (t))
4756 if (TYPE_PTRMEMFUNC_P (t))
4762 if (!TYPE_TEMPLATE_INFO (t))
4764 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4765 fn, data, pfd->visited))
4766 return error_mark_node;
4770 /* Since we're not going to walk subtrees, we have to do this
4772 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4774 return error_mark_node;
4778 /* Check the return type. */
4779 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4780 return error_mark_node;
4782 /* Check the parameter types. Since default arguments are not
4783 instantiated until they are needed, the TYPE_ARG_TYPES may
4784 contain expressions that involve template parameters. But,
4785 no-one should be looking at them yet. And, once they're
4786 instantiated, they don't contain template parameters, so
4787 there's no point in looking at them then, either. */
4791 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4792 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4794 return error_mark_node;
4796 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4797 want walk_tree walking into them itself. */
4803 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4805 return error_mark_node;
4810 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4811 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4813 return error_mark_node;
4818 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4819 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4821 return error_mark_node;
4822 if (DECL_CONTEXT (t)
4823 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4825 return error_mark_node;
4828 case BOUND_TEMPLATE_TEMPLATE_PARM:
4829 /* Record template parameters such as `T' inside `TT<T>'. */
4830 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4831 return error_mark_node;
4834 case TEMPLATE_TEMPLATE_PARM:
4835 case TEMPLATE_TYPE_PARM:
4836 case TEMPLATE_PARM_INDEX:
4837 if (fn && (*fn)(t, data))
4838 return error_mark_node;
4840 return error_mark_node;
4844 /* A template template parameter is encountered. */
4845 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4846 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4847 return error_mark_node;
4849 /* Already substituted template template parameter */
4855 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4856 data, pfd->visited))
4857 return error_mark_node;
4861 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4862 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4863 (TREE_TYPE (t)), fn, data,
4865 return error_mark_node;
4870 /* If there's no type, then this thing must be some expression
4871 involving template parameters. */
4872 if (!fn && !TREE_TYPE (t))
4873 return error_mark_node;
4878 case REINTERPRET_CAST_EXPR:
4879 case CONST_CAST_EXPR:
4880 case STATIC_CAST_EXPR:
4881 case DYNAMIC_CAST_EXPR:
4885 case PSEUDO_DTOR_EXPR:
4887 return error_mark_node;
4891 /* If we do not handle this case specially, we end up walking
4892 the BINFO hierarchy, which is circular, and therefore
4893 confuses walk_tree. */
4895 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4897 return error_mark_node;
4904 /* We didn't find any template parameters we liked. */
4908 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4909 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4910 call FN with the parameter and the DATA.
4911 If FN returns nonzero, the iteration is terminated, and
4912 for_each_template_parm returns 1. Otherwise, the iteration
4913 continues. If FN never returns a nonzero value, the value
4914 returned by for_each_template_parm is 0. If FN is NULL, it is
4915 considered to be the function which always returns 1. */
4918 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4919 struct pointer_set_t *visited)
4921 struct pair_fn_data pfd;
4928 /* Walk the tree. (Conceptually, we would like to walk without
4929 duplicates, but for_each_template_parm_r recursively calls
4930 for_each_template_parm, so we would need to reorganize a fair
4931 bit to use walk_tree_without_duplicates, so we keep our own
4934 pfd.visited = visited;
4936 pfd.visited = pointer_set_create ();
4937 result = walk_tree (&t,
4938 for_each_template_parm_r,
4940 pfd.visited) != NULL_TREE;
4945 pointer_set_destroy (pfd.visited);
4952 /* Returns true if T depends on any template parameter. */
4955 uses_template_parms (tree t)
4958 int saved_processing_template_decl;
4960 saved_processing_template_decl = processing_template_decl;
4961 if (!saved_processing_template_decl)
4962 processing_template_decl = 1;
4964 dependent_p = dependent_type_p (t);
4965 else if (TREE_CODE (t) == TREE_VEC)
4966 dependent_p = any_dependent_template_arguments_p (t);
4967 else if (TREE_CODE (t) == TREE_LIST)
4968 dependent_p = (uses_template_parms (TREE_VALUE (t))
4969 || uses_template_parms (TREE_CHAIN (t)));
4972 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4973 || TREE_CODE (t) == OVERLOAD
4974 || TREE_CODE (t) == BASELINK
4975 || CONSTANT_CLASS_P (t))
4976 dependent_p = (type_dependent_expression_p (t)
4977 || value_dependent_expression_p (t));
4980 gcc_assert (t == error_mark_node);
4981 dependent_p = false;
4984 processing_template_decl = saved_processing_template_decl;
4989 /* Returns true if T depends on any template parameter with level LEVEL. */
4992 uses_template_parms_level (tree t, int level)
4994 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4997 static int tinst_depth;
4998 extern int max_tinst_depth;
4999 #ifdef GATHER_STATISTICS
5002 static int tinst_level_tick;
5003 static int last_template_error_tick;
5005 /* We're starting to instantiate D; record the template instantiation context
5006 for diagnostics and to restore it later. */
5009 push_tinst_level (tree d)
5013 if (tinst_depth >= max_tinst_depth)
5015 /* If the instantiation in question still has unbound template parms,
5016 we don't really care if we can't instantiate it, so just return.
5017 This happens with base instantiation for implicit `typename'. */
5018 if (uses_template_parms (d))
5021 last_template_error_tick = tinst_level_tick;
5022 error ("template instantiation depth exceeds maximum of %d (use "
5023 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5024 max_tinst_depth, d);
5026 print_instantiation_context ();
5031 new = make_tinst_level (d, input_location);
5032 TREE_CHAIN (new) = current_tinst_level;
5033 current_tinst_level = new;
5036 #ifdef GATHER_STATISTICS
5037 if (tinst_depth > depth_reached)
5038 depth_reached = tinst_depth;
5045 /* We're done instantiating this template; return to the instantiation
5049 pop_tinst_level (void)
5051 tree old = current_tinst_level;
5053 /* Restore the filename and line number stashed away when we started
5054 this instantiation. */
5055 input_location = TINST_LOCATION (old);
5056 current_tinst_level = TREE_CHAIN (old);
5061 /* We're instantiating a deferred template; restore the template
5062 instantiation context in which the instantiation was requested, which
5063 is one step out from LEVEL. */
5066 reopen_tinst_level (tree level)
5071 for (t = level; t; t = TREE_CHAIN (t))
5074 current_tinst_level = level;
5078 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5079 vector of template arguments, as for tsubst.
5081 Returns an appropriate tsubst'd friend declaration. */
5084 tsubst_friend_function (tree decl, tree args)
5088 if (TREE_CODE (decl) == FUNCTION_DECL
5089 && DECL_TEMPLATE_INSTANTIATION (decl)
5090 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5091 /* This was a friend declared with an explicit template
5092 argument list, e.g.:
5096 to indicate that f was a template instantiation, not a new
5097 function declaration. Now, we have to figure out what
5098 instantiation of what template. */
5100 tree template_id, arglist, fns;
5103 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5105 /* Friend functions are looked up in the containing namespace scope.
5106 We must enter that scope, to avoid finding member functions of the
5107 current cless with same name. */
5108 push_nested_namespace (ns);
5109 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5110 tf_error | tf_warning, NULL_TREE);
5111 pop_nested_namespace (ns);
5112 arglist = tsubst (DECL_TI_ARGS (decl), args,
5113 tf_error | tf_warning, NULL_TREE);
5114 template_id = lookup_template_function (fns, arglist);
5116 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5117 tmpl = determine_specialization (template_id, new_friend,
5119 /*need_member_template=*/0,
5120 TREE_VEC_LENGTH (args));
5121 return instantiate_template (tmpl, new_args, tf_error);
5124 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5126 /* The NEW_FRIEND will look like an instantiation, to the
5127 compiler, but is not an instantiation from the point of view of
5128 the language. For example, we might have had:
5130 template <class T> struct S {
5131 template <class U> friend void f(T, U);
5134 Then, in S<int>, template <class U> void f(int, U) is not an
5135 instantiation of anything. */
5136 if (new_friend == error_mark_node)
5137 return error_mark_node;
5139 DECL_USE_TEMPLATE (new_friend) = 0;
5140 if (TREE_CODE (decl) == TEMPLATE_DECL)
5142 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5143 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5144 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5147 /* The mangled name for the NEW_FRIEND is incorrect. The function
5148 is not a template instantiation and should not be mangled like
5149 one. Therefore, we forget the mangling here; we'll recompute it
5150 later if we need it. */
5151 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5153 SET_DECL_RTL (new_friend, NULL_RTX);
5154 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5157 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5160 tree new_friend_template_info;
5161 tree new_friend_result_template_info;
5163 int new_friend_is_defn;
5165 /* We must save some information from NEW_FRIEND before calling
5166 duplicate decls since that function will free NEW_FRIEND if
5168 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5169 new_friend_is_defn =
5170 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5171 (template_for_substitution (new_friend)))
5173 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5175 /* This declaration is a `primary' template. */
5176 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5178 new_friend_result_template_info
5179 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5182 new_friend_result_template_info = NULL_TREE;
5184 /* Inside pushdecl_namespace_level, we will push into the
5185 current namespace. However, the friend function should go
5186 into the namespace of the template. */
5187 ns = decl_namespace_context (new_friend);
5188 push_nested_namespace (ns);
5189 old_decl = pushdecl_namespace_level (new_friend);
5190 pop_nested_namespace (ns);
5192 if (old_decl != new_friend)
5194 /* This new friend declaration matched an existing
5195 declaration. For example, given:
5197 template <class T> void f(T);
5198 template <class U> class C {
5199 template <class T> friend void f(T) {}
5202 the friend declaration actually provides the definition
5203 of `f', once C has been instantiated for some type. So,
5204 old_decl will be the out-of-class template declaration,
5205 while new_friend is the in-class definition.
5207 But, if `f' was called before this point, the
5208 instantiation of `f' will have DECL_TI_ARGS corresponding
5209 to `T' but not to `U', references to which might appear
5210 in the definition of `f'. Previously, the most general
5211 template for an instantiation of `f' was the out-of-class
5212 version; now it is the in-class version. Therefore, we
5213 run through all specialization of `f', adding to their
5214 DECL_TI_ARGS appropriately. In particular, they need a
5215 new set of outer arguments, corresponding to the
5216 arguments for this class instantiation.
5218 The same situation can arise with something like this:
5221 template <class T> class C {
5225 when `C<int>' is instantiated. Now, `f(int)' is defined
5228 if (!new_friend_is_defn)
5229 /* On the other hand, if the in-class declaration does
5230 *not* provide a definition, then we don't want to alter
5231 existing definitions. We can just leave everything
5236 /* Overwrite whatever template info was there before, if
5237 any, with the new template information pertaining to
5239 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5241 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5242 reregister_specialization (new_friend,
5243 most_general_template (old_decl),
5248 tree new_friend_args;
5250 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5251 = new_friend_result_template_info;
5253 new_friend_args = TI_ARGS (new_friend_template_info);
5254 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5258 tree spec = TREE_VALUE (t);
5261 = add_outermost_template_args (new_friend_args,
5262 DECL_TI_ARGS (spec));
5265 /* Now, since specializations are always supposed to
5266 hang off of the most general template, we must move
5268 t = most_general_template (old_decl);
5271 DECL_TEMPLATE_SPECIALIZATIONS (t)
5272 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5273 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5274 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5279 /* The information from NEW_FRIEND has been merged into OLD_DECL
5280 by duplicate_decls. */
5281 new_friend = old_decl;
5286 tree context = DECL_CONTEXT (new_friend);
5290 template <class T> class C {
5291 template <class U> friend void C1<U>::f (); // case 1
5292 friend void C2<T>::f (); // case 2
5294 we only need to make sure CONTEXT is a complete type for
5295 case 2. To distinguish between the two cases, we note that
5296 CONTEXT of case 1 remains dependent type after tsubst while
5297 this isn't true for case 2. */
5298 ++processing_template_decl;
5299 dependent_p = dependent_type_p (context);
5300 --processing_template_decl;
5303 && !complete_type_or_else (context, NULL_TREE))
5304 return error_mark_node;
5306 if (COMPLETE_TYPE_P (context))
5308 /* Check to see that the declaration is really present, and,
5309 possibly obtain an improved declaration. */
5310 tree fn = check_classfn (context,
5311 new_friend, NULL_TREE);
5321 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5322 template arguments, as for tsubst.
5324 Returns an appropriate tsubst'd friend type or error_mark_node on
5328 tsubst_friend_class (tree friend_tmpl, tree args)
5334 context = DECL_CONTEXT (friend_tmpl);
5338 if (TREE_CODE (context) == NAMESPACE_DECL)
5339 push_nested_namespace (context);
5341 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5344 /* First, we look for a class template. */
5345 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5347 /* But, if we don't find one, it might be because we're in a
5348 situation like this:
5356 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5357 for `S<int>', not the TEMPLATE_DECL. */
5358 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5360 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5361 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5364 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5366 /* The friend template has already been declared. Just
5367 check to see that the declarations match, and install any new
5368 default parameters. We must tsubst the default parameters,
5369 of course. We only need the innermost template parameters
5370 because that is all that redeclare_class_template will look
5372 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5373 > TMPL_ARGS_DEPTH (args))
5376 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5377 args, tf_error | tf_warning);
5378 redeclare_class_template (TREE_TYPE (tmpl), parms);
5381 friend_type = TREE_TYPE (tmpl);
5385 /* The friend template has not already been declared. In this
5386 case, the instantiation of the template class will cause the
5387 injection of this template into the global scope. */
5388 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5390 /* The new TMPL is not an instantiation of anything, so we
5391 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5392 the new type because that is supposed to be the corresponding
5393 template decl, i.e., TMPL. */
5394 DECL_USE_TEMPLATE (tmpl) = 0;
5395 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5396 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5397 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5398 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5400 /* Inject this template into the global scope. */
5401 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5406 if (TREE_CODE (context) == NAMESPACE_DECL)
5407 pop_nested_namespace (context);
5409 pop_nested_class ();
5415 /* Returns zero if TYPE cannot be completed later due to circularity.
5416 Otherwise returns one. */
5419 can_complete_type_without_circularity (tree type)
5421 if (type == NULL_TREE || type == error_mark_node)
5423 else if (COMPLETE_TYPE_P (type))
5425 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5426 return can_complete_type_without_circularity (TREE_TYPE (type));
5427 else if (CLASS_TYPE_P (type)
5428 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5435 instantiate_class_template (tree type)
5437 tree template, args, pattern, t, member;
5442 if (type == error_mark_node)
5443 return error_mark_node;
5445 if (TYPE_BEING_DEFINED (type)
5446 || COMPLETE_TYPE_P (type)
5447 || dependent_type_p (type))
5450 /* Figure out which template is being instantiated. */
5451 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5452 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5454 /* Figure out which arguments are being used to do the
5456 args = CLASSTYPE_TI_ARGS (type);
5458 /* Determine what specialization of the original template to
5460 t = most_specialized_class (template, args);
5461 if (t == error_mark_node)
5463 const char *str = "candidates are:";
5464 error ("ambiguous class template instantiation for %q#T", type);
5465 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5468 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5470 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5474 TYPE_BEING_DEFINED (type) = 1;
5475 return error_mark_node;
5479 pattern = TREE_TYPE (t);
5481 pattern = TREE_TYPE (template);
5483 /* If the template we're instantiating is incomplete, then clearly
5484 there's nothing we can do. */
5485 if (!COMPLETE_TYPE_P (pattern))
5488 /* If we've recursively instantiated too many templates, stop. */
5489 if (! push_tinst_level (type))
5492 /* Now we're really doing the instantiation. Mark the type as in
5493 the process of being defined. */
5494 TYPE_BEING_DEFINED (type) = 1;
5496 /* We may be in the middle of deferred access check. Disable
5498 push_deferring_access_checks (dk_no_deferred);
5500 push_to_top_level ();
5504 /* This TYPE is actually an instantiation of a partial
5505 specialization. We replace the innermost set of ARGS with
5506 the arguments appropriate for substitution. For example,
5509 template <class T> struct S {};
5510 template <class T> struct S<T*> {};
5512 and supposing that we are instantiating S<int*>, ARGS will
5513 present be {int*} but we need {int}. */
5515 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5518 /* If there were multiple levels in ARGS, replacing the
5519 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5520 want, so we make a copy first. */
5521 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5523 args = copy_node (args);
5524 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5530 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5532 /* Set the input location to the template definition. This is needed
5533 if tsubsting causes an error. */
5534 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (pattern));
5536 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5537 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5538 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5539 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5540 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5541 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5542 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5543 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5544 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5545 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5546 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5547 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5548 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5549 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5550 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5551 if (ANON_AGGR_TYPE_P (pattern))
5552 SET_ANON_AGGR_TYPE_P (type);
5554 pbinfo = TYPE_BINFO (pattern);
5556 /* We should never instantiate a nested class before its enclosing
5557 class; we need to look up the nested class by name before we can
5558 instantiate it, and that lookup should instantiate the enclosing
5560 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5561 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5562 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5564 base_list = NULL_TREE;
5565 if (BINFO_N_BASE_BINFOS (pbinfo))
5568 tree context = TYPE_CONTEXT (type);
5572 /* We must enter the scope containing the type, as that is where
5573 the accessibility of types named in dependent bases are
5575 pushed_scope = push_scope (context ? context : global_namespace);
5577 /* Substitute into each of the bases to determine the actual
5579 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5582 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5584 /* Substitute to figure out the base class. */
5585 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5586 if (base == error_mark_node)
5589 base_list = tree_cons (access, base, base_list);
5590 if (BINFO_VIRTUAL_P (pbase_binfo))
5591 TREE_TYPE (base_list) = integer_type_node;
5594 /* The list is now in reverse order; correct that. */
5595 base_list = nreverse (base_list);
5598 pop_scope (pushed_scope);
5600 /* Now call xref_basetypes to set up all the base-class
5602 xref_basetypes (type, base_list);
5605 /* Now that our base classes are set up, enter the scope of the
5606 class, so that name lookups into base classes, etc. will work
5607 correctly. This is precisely analogous to what we do in
5608 begin_class_definition when defining an ordinary non-template
5612 /* Now members are processed in the order of declaration. */
5613 for (member = CLASSTYPE_DECL_LIST (pattern);
5614 member; member = TREE_CHAIN (member))
5616 tree t = TREE_VALUE (member);
5618 if (TREE_PURPOSE (member))
5622 /* Build new CLASSTYPE_NESTED_UTDS. */
5625 tree name = TYPE_IDENTIFIER (tag);
5627 bool class_template_p;
5629 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5630 && TYPE_LANG_SPECIFIC (tag)
5631 && CLASSTYPE_IS_TEMPLATE (tag));
5632 /* If the member is a class template, then -- even after
5633 substitution -- there may be dependent types in the
5634 template argument list for the class. We increment
5635 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5636 that function will assume that no types are dependent
5637 when outside of a template. */
5638 if (class_template_p)
5639 ++processing_template_decl;
5640 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5641 if (class_template_p)
5642 --processing_template_decl;
5643 if (newtag == error_mark_node)
5646 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5648 if (class_template_p)
5649 /* Unfortunately, lookup_template_class sets
5650 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5651 instantiation (i.e., for the type of a member
5652 template class nested within a template class.)
5653 This behavior is required for
5654 maybe_process_partial_specialization to work
5655 correctly, but is not accurate in this case;
5656 the TAG is not an instantiation of anything.
5657 (The corresponding TEMPLATE_DECL is an
5658 instantiation, but the TYPE is not.) */
5659 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5661 /* Now, we call pushtag to put this NEWTAG into the scope of
5662 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5663 pushtag calling push_template_decl. We don't have to do
5664 this for enums because it will already have been done in
5667 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5668 pushtag (name, newtag, /*globalize=*/0);
5671 else if (TREE_CODE (t) == FUNCTION_DECL
5672 || DECL_FUNCTION_TEMPLATE_P (t))
5674 /* Build new TYPE_METHODS. */
5677 if (TREE_CODE (t) == TEMPLATE_DECL)
5678 ++processing_template_decl;
5679 r = tsubst (t, args, tf_error, NULL_TREE);
5680 if (TREE_CODE (t) == TEMPLATE_DECL)
5681 --processing_template_decl;
5682 set_current_access_from_decl (r);
5683 grok_special_member_properties (r);
5684 finish_member_declaration (r);
5688 /* Build new TYPE_FIELDS. */
5690 if (TREE_CODE (t) != CONST_DECL)
5694 /* The the file and line for this declaration, to
5695 assist in error message reporting. Since we
5696 called push_tinst_level above, we don't need to
5698 input_location = DECL_SOURCE_LOCATION (t);
5700 if (TREE_CODE (t) == TEMPLATE_DECL)
5701 ++processing_template_decl;
5702 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5703 if (TREE_CODE (t) == TEMPLATE_DECL)
5704 --processing_template_decl;
5705 if (TREE_CODE (r) == VAR_DECL)
5709 if (DECL_INITIALIZED_IN_CLASS_P (r))
5710 init = tsubst_expr (DECL_INITIAL (t), args,
5711 tf_error | tf_warning, NULL_TREE);
5715 finish_static_data_member_decl
5716 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5718 if (DECL_INITIALIZED_IN_CLASS_P (r))
5719 check_static_variable_definition (r, TREE_TYPE (r));
5721 else if (TREE_CODE (r) == FIELD_DECL)
5723 /* Determine whether R has a valid type and can be
5724 completed later. If R is invalid, then it is
5725 replaced by error_mark_node so that it will not be
5726 added to TYPE_FIELDS. */
5727 tree rtype = TREE_TYPE (r);
5728 if (can_complete_type_without_circularity (rtype))
5729 complete_type (rtype);
5731 if (!COMPLETE_TYPE_P (rtype))
5733 cxx_incomplete_type_error (r, rtype);
5734 r = error_mark_node;
5738 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5739 such a thing will already have been added to the field
5740 list by tsubst_enum in finish_member_declaration in the
5741 CLASSTYPE_NESTED_UTDS case above. */
5742 if (!(TREE_CODE (r) == TYPE_DECL
5743 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5744 && DECL_ARTIFICIAL (r)))
5746 set_current_access_from_decl (r);
5747 finish_member_declaration (r);
5754 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5756 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5758 tree friend_type = t;
5759 bool adjust_processing_template_decl = false;
5761 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5763 friend_type = tsubst_friend_class (friend_type, args);
5764 adjust_processing_template_decl = true;
5766 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5768 friend_type = tsubst (friend_type, args,
5769 tf_error | tf_warning, NULL_TREE);
5770 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5771 friend_type = TREE_TYPE (friend_type);
5772 adjust_processing_template_decl = true;
5774 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5776 friend_type = tsubst (friend_type, args,
5777 tf_error | tf_warning, NULL_TREE);
5778 /* Bump processing_template_decl for correct
5779 dependent_type_p calculation. */
5780 ++processing_template_decl;
5781 if (dependent_type_p (friend_type))
5782 adjust_processing_template_decl = true;
5783 --processing_template_decl;
5785 else if (uses_template_parms (friend_type))
5786 friend_type = tsubst (friend_type, args,
5787 tf_error | tf_warning, NULL_TREE);
5788 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5789 friend_type = friend_type;
5792 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5794 /* The call to xref_tag_from_type does injection for friend
5796 push_nested_namespace (ns);
5798 xref_tag_from_type (friend_type, NULL_TREE,
5799 /*tag_scope=*/ts_global);
5800 pop_nested_namespace (ns);
5803 if (adjust_processing_template_decl)
5804 /* Trick make_friend_class into realizing that the friend
5805 we're adding is a template, not an ordinary class. It's
5806 important that we use make_friend_class since it will
5807 perform some error-checking and output cross-reference
5809 ++processing_template_decl;
5811 if (friend_type != error_mark_node)
5812 make_friend_class (type, friend_type, /*complain=*/false);
5814 if (adjust_processing_template_decl)
5815 --processing_template_decl;
5819 /* Build new DECL_FRIENDLIST. */
5822 /* The the file and line for this declaration, to
5823 assist in error message reporting. Since we
5824 called push_tinst_level above, we don't need to
5826 input_location = DECL_SOURCE_LOCATION (t);
5828 if (TREE_CODE (t) == TEMPLATE_DECL)
5830 ++processing_template_decl;
5831 push_deferring_access_checks (dk_no_check);
5834 r = tsubst_friend_function (t, args);
5835 add_friend (type, r, /*complain=*/false);
5836 if (TREE_CODE (t) == TEMPLATE_DECL)
5838 pop_deferring_access_checks ();
5839 --processing_template_decl;
5845 /* Set the file and line number information to whatever is given for
5846 the class itself. This puts error messages involving generated
5847 implicit functions at a predictable point, and the same point
5848 that would be used for non-template classes. */
5849 typedecl = TYPE_MAIN_DECL (type);
5850 input_location = DECL_SOURCE_LOCATION (typedecl);
5852 unreverse_member_declarations (type);
5853 finish_struct_1 (type);
5854 TYPE_BEING_DEFINED (type) = 0;
5856 /* Now that the class is complete, instantiate default arguments for
5857 any member functions. We don't do this earlier because the
5858 default arguments may reference members of the class. */
5859 if (!PRIMARY_TEMPLATE_P (template))
5860 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5861 if (TREE_CODE (t) == FUNCTION_DECL
5862 /* Implicitly generated member functions will not have template
5863 information; they are not instantiations, but instead are
5864 created "fresh" for each instantiation. */
5865 && DECL_TEMPLATE_INFO (t))
5866 tsubst_default_arguments (t);
5869 pop_from_top_level ();
5870 pop_deferring_access_checks ();
5873 /* The vtable for a template class can be emitted in any translation
5874 unit in which the class is instantiated. When there is no key
5875 method, however, finish_struct_1 will already have added TYPE to
5876 the keyed_classes list. */
5877 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5878 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5884 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5890 else if (TYPE_P (t))
5891 r = tsubst (t, args, complain, in_decl);
5894 r = tsubst_expr (t, args, complain, in_decl);
5896 if (!uses_template_parms (r))
5898 /* Sometimes, one of the args was an expression involving a
5899 template constant parameter, like N - 1. Now that we've
5900 tsubst'd, we might have something like 2 - 1. This will
5901 confuse lookup_template_class, so we do constant folding
5902 here. We have to unset processing_template_decl, to fool
5903 tsubst_copy_and_build() into building an actual tree. */
5905 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5906 as simple as it's going to get, and trying to reprocess
5907 the trees will break. Once tsubst_expr et al DTRT for
5908 non-dependent exprs, this code can go away, as the type
5909 will always be set. */
5912 int saved_processing_template_decl = processing_template_decl;
5913 processing_template_decl = 0;
5914 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5915 tf_error, /*in_decl=*/NULL_TREE,
5916 /*function_p=*/false);
5917 processing_template_decl = saved_processing_template_decl;
5925 /* Substitute ARGS into the vector or list of template arguments T. */
5928 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5930 int len = TREE_VEC_LENGTH (t);
5931 int need_new = 0, i;
5932 tree *elts = alloca (len * sizeof (tree));
5934 for (i = 0; i < len; i++)
5936 tree orig_arg = TREE_VEC_ELT (t, i);
5939 if (TREE_CODE (orig_arg) == TREE_VEC)
5940 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5942 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5944 if (new_arg == error_mark_node)
5945 return error_mark_node;
5948 if (new_arg != orig_arg)
5955 t = make_tree_vec (len);
5956 for (i = 0; i < len; i++)
5957 TREE_VEC_ELT (t, i) = elts[i];
5962 /* Return the result of substituting ARGS into the template parameters
5963 given by PARMS. If there are m levels of ARGS and m + n levels of
5964 PARMS, then the result will contain n levels of PARMS. For
5965 example, if PARMS is `template <class T> template <class U>
5966 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5967 result will be `template <int*, double, class V>'. */
5970 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5975 for (new_parms = &r;
5976 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5977 new_parms = &(TREE_CHAIN (*new_parms)),
5978 parms = TREE_CHAIN (parms))
5981 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5984 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5986 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5987 tree default_value = TREE_PURPOSE (tuple);
5988 tree parm_decl = TREE_VALUE (tuple);
5990 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5991 default_value = tsubst_template_arg (default_value, args,
5992 complain, NULL_TREE);
5994 tuple = build_tree_list (default_value, parm_decl);
5995 TREE_VEC_ELT (new_vec, i) = tuple;
5999 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6000 - TMPL_ARGS_DEPTH (args)),
6001 new_vec, NULL_TREE);
6007 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6008 type T. If T is not an aggregate or enumeration type, it is
6009 handled as if by tsubst. IN_DECL is as for tsubst. If
6010 ENTERING_SCOPE is nonzero, T is the context for a template which
6011 we are presently tsubst'ing. Return the substituted value. */
6014 tsubst_aggr_type (tree t,
6016 tsubst_flags_t complain,
6023 switch (TREE_CODE (t))
6026 if (TYPE_PTRMEMFUNC_P (t))
6027 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6029 /* Else fall through. */
6032 if (TYPE_TEMPLATE_INFO (t))
6038 /* First, determine the context for the type we are looking
6040 context = TYPE_CONTEXT (t);
6042 context = tsubst_aggr_type (context, args, complain,
6043 in_decl, /*entering_scope=*/1);
6045 /* Then, figure out what arguments are appropriate for the
6046 type we are trying to find. For example, given:
6048 template <class T> struct S;
6049 template <class T, class U> void f(T, U) { S<U> su; }
6051 and supposing that we are instantiating f<int, double>,
6052 then our ARGS will be {int, double}, but, when looking up
6053 S we only want {double}. */
6054 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6056 if (argvec == error_mark_node)
6057 return error_mark_node;
6059 r = lookup_template_class (t, argvec, in_decl, context,
6060 entering_scope, complain);
6062 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6065 /* This is not a template type, so there's nothing to do. */
6069 return tsubst (t, args, complain, in_decl);
6073 /* Substitute into the default argument ARG (a default argument for
6074 FN), which has the indicated TYPE. */
6077 tsubst_default_argument (tree fn, tree type, tree arg)
6079 tree saved_class_ptr = NULL_TREE;
6080 tree saved_class_ref = NULL_TREE;
6082 /* This default argument came from a template. Instantiate the
6083 default argument here, not in tsubst. In the case of
6092 we must be careful to do name lookup in the scope of S<T>,
6093 rather than in the current class. */
6094 push_access_scope (fn);
6095 /* The default argument expression should not be considered to be
6096 within the scope of FN. Since push_access_scope sets
6097 current_function_decl, we must explicitly clear it here. */
6098 current_function_decl = NULL_TREE;
6099 /* The "this" pointer is not valid in a default argument. */
6102 saved_class_ptr = current_class_ptr;
6103 cp_function_chain->x_current_class_ptr = NULL_TREE;
6104 saved_class_ref = current_class_ref;
6105 cp_function_chain->x_current_class_ref = NULL_TREE;
6108 push_deferring_access_checks(dk_no_deferred);
6109 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6110 tf_error | tf_warning, NULL_TREE);
6111 pop_deferring_access_checks();
6113 /* Restore the "this" pointer. */
6116 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6117 cp_function_chain->x_current_class_ref = saved_class_ref;
6120 pop_access_scope (fn);
6122 /* Make sure the default argument is reasonable. */
6123 arg = check_default_argument (type, arg);
6128 /* Substitute into all the default arguments for FN. */
6131 tsubst_default_arguments (tree fn)
6136 tmpl_args = DECL_TI_ARGS (fn);
6138 /* If this function is not yet instantiated, we certainly don't need
6139 its default arguments. */
6140 if (uses_template_parms (tmpl_args))
6143 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6145 arg = TREE_CHAIN (arg))
6146 if (TREE_PURPOSE (arg))
6147 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6149 TREE_PURPOSE (arg));
6152 /* Substitute the ARGS into the T, which is a _DECL. Return the
6153 result of the substitution. Issue error and warning messages under
6154 control of COMPLAIN. */
6157 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6159 location_t saved_loc;
6163 /* Set the filename and linenumber to improve error-reporting. */
6164 saved_loc = input_location;
6165 input_location = DECL_SOURCE_LOCATION (t);
6167 switch (TREE_CODE (t))
6171 /* We can get here when processing a member function template,
6172 member class template, and template template parameter of
6173 a template class. */
6174 tree decl = DECL_TEMPLATE_RESULT (t);
6179 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6181 /* Template template parameter is treated here. */
6182 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6183 if (new_type == error_mark_node)
6184 return error_mark_node;
6187 TREE_CHAIN (r) = NULL_TREE;
6188 TREE_TYPE (r) = new_type;
6189 DECL_TEMPLATE_RESULT (r)
6190 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6191 DECL_TEMPLATE_PARMS (r)
6192 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6194 TYPE_NAME (new_type) = r;
6198 /* We might already have an instance of this template.
6199 The ARGS are for the surrounding class type, so the
6200 full args contain the tsubst'd args for the context,
6201 plus the innermost args from the template decl. */
6202 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6203 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6204 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6205 full_args = tsubst_template_args (tmpl_args, args,
6208 /* tsubst_template_args doesn't copy the vector if
6209 nothing changed. But, *something* should have
6211 gcc_assert (full_args != tmpl_args);
6213 spec = retrieve_specialization (t, full_args,
6214 /*class_specializations_p=*/true);
6215 if (spec != NULL_TREE)
6221 /* Make a new template decl. It will be similar to the
6222 original, but will record the current template arguments.
6223 We also create a new function declaration, which is just
6224 like the old one, but points to this new template, rather
6225 than the old one. */
6227 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6228 TREE_CHAIN (r) = NULL_TREE;
6231 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6233 /*entering_scope=*/1);
6234 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6236 if (TREE_CODE (decl) == TYPE_DECL)
6238 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6239 if (new_type == error_mark_node)
6240 return error_mark_node;
6242 TREE_TYPE (r) = new_type;
6243 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6244 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6245 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6249 tree new_decl = tsubst (decl, args, complain, in_decl);
6250 if (new_decl == error_mark_node)
6251 return error_mark_node;
6253 DECL_TEMPLATE_RESULT (r) = new_decl;
6254 DECL_TI_TEMPLATE (new_decl) = r;
6255 TREE_TYPE (r) = TREE_TYPE (new_decl);
6256 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6259 SET_DECL_IMPLICIT_INSTANTIATION (r);
6260 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6261 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6263 /* The template parameters for this new template are all the
6264 template parameters for the old template, except the
6265 outermost level of parameters. */
6266 DECL_TEMPLATE_PARMS (r)
6267 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6270 if (PRIMARY_TEMPLATE_P (t))
6271 DECL_PRIMARY_TEMPLATE (r) = r;
6273 if (TREE_CODE (decl) != TYPE_DECL)
6274 /* Record this non-type partial instantiation. */
6275 register_specialization (r, t,
6276 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6283 tree argvec = NULL_TREE;
6291 /* Nobody should be tsubst'ing into non-template functions. */
6292 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6294 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6299 /* If T is not dependent, just return it. We have to
6300 increment PROCESSING_TEMPLATE_DECL because
6301 value_dependent_expression_p assumes that nothing is
6302 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6303 ++processing_template_decl;
6304 dependent_p = value_dependent_expression_p (t);
6305 --processing_template_decl;
6309 /* Calculate the most general template of which R is a
6310 specialization, and the complete set of arguments used to
6312 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6313 argvec = tsubst_template_args (DECL_TI_ARGS
6314 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6315 args, complain, in_decl);
6317 /* Check to see if we already have this specialization. */
6318 spec = retrieve_specialization (gen_tmpl, argvec,
6319 /*class_specializations_p=*/false);
6327 /* We can see more levels of arguments than parameters if
6328 there was a specialization of a member template, like
6331 template <class T> struct S { template <class U> void f(); }
6332 template <> template <class U> void S<int>::f(U);
6334 Here, we'll be substituting into the specialization,
6335 because that's where we can find the code we actually
6336 want to generate, but we'll have enough arguments for
6337 the most general template.
6339 We also deal with the peculiar case:
6341 template <class T> struct S {
6342 template <class U> friend void f();
6344 template <class U> void f() {}
6346 template void f<double>();
6348 Here, the ARGS for the instantiation of will be {int,
6349 double}. But, we only need as many ARGS as there are
6350 levels of template parameters in CODE_PATTERN. We are
6351 careful not to get fooled into reducing the ARGS in
6354 template <class T> struct S { template <class U> void f(U); }
6355 template <class T> template <> void S<T>::f(int) {}
6357 which we can spot because the pattern will be a
6358 specialization in this case. */
6359 args_depth = TMPL_ARGS_DEPTH (args);
6361 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6362 if (args_depth > parms_depth
6363 && !DECL_TEMPLATE_SPECIALIZATION (t))
6364 args = get_innermost_template_args (args, parms_depth);
6368 /* This special case arises when we have something like this:
6370 template <class T> struct S {
6371 friend void f<int>(int, double);
6374 Here, the DECL_TI_TEMPLATE for the friend declaration
6375 will be an IDENTIFIER_NODE. We are being called from
6376 tsubst_friend_function, and we want only to create a
6377 new decl (R) with appropriate types so that we can call
6378 determine_specialization. */
6379 gen_tmpl = NULL_TREE;
6382 if (DECL_CLASS_SCOPE_P (t))
6384 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6388 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6389 complain, t, /*entering_scope=*/1);
6394 ctx = DECL_CONTEXT (t);
6396 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6397 if (type == error_mark_node)
6398 return error_mark_node;
6400 /* We do NOT check for matching decls pushed separately at this
6401 point, as they may not represent instantiations of this
6402 template, and in any case are considered separate under the
6405 DECL_USE_TEMPLATE (r) = 0;
6406 TREE_TYPE (r) = type;
6407 /* Clear out the mangled name and RTL for the instantiation. */
6408 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6409 SET_DECL_RTL (r, NULL_RTX);
6410 DECL_INITIAL (r) = NULL_TREE;
6411 DECL_CONTEXT (r) = ctx;
6413 if (member && DECL_CONV_FN_P (r))
6414 /* Type-conversion operator. Reconstruct the name, in
6415 case it's the name of one of the template's parameters. */
6416 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6418 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6420 DECL_RESULT (r) = NULL_TREE;
6422 TREE_STATIC (r) = 0;
6423 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6424 DECL_EXTERNAL (r) = 1;
6425 /* If this is an instantiation of a function with internal
6426 linkage, we already know what object file linkage will be
6427 assigned to the instantiation. */
6428 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6429 DECL_DEFER_OUTPUT (r) = 0;
6430 TREE_CHAIN (r) = NULL_TREE;
6431 DECL_PENDING_INLINE_INFO (r) = 0;
6432 DECL_PENDING_INLINE_P (r) = 0;
6433 DECL_SAVED_TREE (r) = NULL_TREE;
6435 if (DECL_CLONED_FUNCTION (r))
6437 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6439 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6440 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6443 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6444 this in the special friend case mentioned above where
6445 GEN_TMPL is NULL. */
6448 DECL_TEMPLATE_INFO (r)
6449 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6450 SET_DECL_IMPLICIT_INSTANTIATION (r);
6451 register_specialization (r, gen_tmpl, argvec);
6453 /* We're not supposed to instantiate default arguments
6454 until they are called, for a template. But, for a
6457 template <class T> void f ()
6458 { extern void g(int i = T()); }
6460 we should do the substitution when the template is
6461 instantiated. We handle the member function case in
6462 instantiate_class_template since the default arguments
6463 might refer to other members of the class. */
6465 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6466 && !uses_template_parms (argvec))
6467 tsubst_default_arguments (r);
6470 /* Copy the list of befriending classes. */
6471 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6473 friends = &TREE_CHAIN (*friends))
6475 *friends = copy_node (*friends);
6476 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6481 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6483 maybe_retrofit_in_chrg (r);
6484 if (DECL_CONSTRUCTOR_P (r))
6485 grok_ctor_properties (ctx, r);
6486 /* If this is an instantiation of a member template, clone it.
6487 If it isn't, that'll be handled by
6488 clone_constructors_and_destructors. */
6489 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6490 clone_function_decl (r, /*update_method_vec_p=*/0);
6492 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6493 grok_op_properties (r, DECL_FRIEND_P (r),
6494 (complain & tf_error) != 0);
6496 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6497 SET_DECL_FRIEND_CONTEXT (r,
6498 tsubst (DECL_FRIEND_CONTEXT (t),
6499 args, complain, in_decl));
6508 if (DECL_TEMPLATE_PARM_P (t))
6509 SET_DECL_TEMPLATE_PARM_P (r);
6511 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6512 TREE_TYPE (r) = type;
6513 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6515 if (DECL_INITIAL (r))
6517 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6518 DECL_INITIAL (r) = TREE_TYPE (r);
6520 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6524 DECL_CONTEXT (r) = NULL_TREE;
6526 if (!DECL_TEMPLATE_PARM_P (r))
6527 DECL_ARG_TYPE (r) = type_passed_as (type);
6529 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6530 complain, TREE_CHAIN (t));
6539 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6540 if (type == error_mark_node)
6541 return error_mark_node;
6542 TREE_TYPE (r) = type;
6543 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6545 /* We don't have to set DECL_CONTEXT here; it is set by
6546 finish_member_declaration. */
6547 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6549 TREE_CHAIN (r) = NULL_TREE;
6550 if (VOID_TYPE_P (type))
6551 cp_error_at ("instantiation of %qD as type %qT", r, type);
6558 /* It is not a dependent using decl any more. */
6559 TREE_TYPE (r) = void_type_node;
6561 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6563 = tsubst_copy (DECL_NAME (t), args, complain, in_decl);
6564 TREE_CHAIN (r) = NULL_TREE;
6571 tree argvec = NULL_TREE;
6572 tree gen_tmpl = NULL_TREE;
6574 tree tmpl = NULL_TREE;
6576 tree type = NULL_TREE;
6579 if (TREE_CODE (t) == TYPE_DECL)
6581 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6582 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6583 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6585 /* If this is the canonical decl, we don't have to
6586 mess with instantiations, and often we can't (for
6587 typename, template type parms and such). Note that
6588 TYPE_NAME is not correct for the above test if
6589 we've copied the type for a typedef. */
6590 r = TYPE_NAME (type);
6595 /* Assume this is a non-local variable. */
6598 if (TYPE_P (CP_DECL_CONTEXT (t)))
6599 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6601 in_decl, /*entering_scope=*/1);
6602 else if (DECL_NAMESPACE_SCOPE_P (t))
6603 ctx = DECL_CONTEXT (t);
6606 /* Subsequent calls to pushdecl will fill this in. */
6611 /* Check to see if we already have this specialization. */
6614 tmpl = DECL_TI_TEMPLATE (t);
6615 gen_tmpl = most_general_template (tmpl);
6616 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6617 spec = retrieve_specialization (gen_tmpl, argvec,
6618 /*class_specializations_p=*/false);
6621 spec = retrieve_local_specialization (t);
6630 if (TREE_CODE (r) == VAR_DECL)
6632 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6633 if (type == error_mark_node)
6634 return error_mark_node;
6635 type = complete_type (type);
6636 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6637 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6638 type = check_var_type (DECL_NAME (r), type);
6640 else if (DECL_SELF_REFERENCE_P (t))
6641 SET_DECL_SELF_REFERENCE_P (r);
6642 TREE_TYPE (r) = type;
6643 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6644 DECL_CONTEXT (r) = ctx;
6645 /* Clear out the mangled name and RTL for the instantiation. */
6646 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6647 SET_DECL_RTL (r, NULL_RTX);
6649 /* Don't try to expand the initializer until someone tries to use
6650 this variable; otherwise we run into circular dependencies. */
6651 DECL_INITIAL (r) = NULL_TREE;
6652 SET_DECL_RTL (r, NULL_RTX);
6653 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6655 /* Even if the original location is out of scope, the newly
6656 substituted one is not. */
6657 if (TREE_CODE (r) == VAR_DECL)
6659 DECL_DEAD_FOR_LOCAL (r) = 0;
6660 DECL_INITIALIZED_P (r) = 0;
6665 /* A static data member declaration is always marked
6666 external when it is declared in-class, even if an
6667 initializer is present. We mimic the non-template
6669 DECL_EXTERNAL (r) = 1;
6671 register_specialization (r, gen_tmpl, argvec);
6672 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6673 SET_DECL_IMPLICIT_INSTANTIATION (r);
6676 register_local_specialization (r, t);
6678 TREE_CHAIN (r) = NULL_TREE;
6687 /* Restore the file and line information. */
6688 input_location = saved_loc;
6693 /* Substitute into the ARG_TYPES of a function type. */
6696 tsubst_arg_types (tree arg_types,
6698 tsubst_flags_t complain,
6701 tree remaining_arg_types;
6704 if (!arg_types || arg_types == void_list_node)
6707 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6708 args, complain, in_decl);
6709 if (remaining_arg_types == error_mark_node)
6710 return error_mark_node;
6712 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6713 if (type == error_mark_node)
6714 return error_mark_node;
6715 if (VOID_TYPE_P (type))
6717 if (complain & tf_error)
6719 error ("invalid parameter type %qT", type);
6721 cp_error_at ("in declaration %qD", in_decl);
6723 return error_mark_node;
6726 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6727 top-level qualifiers as required. */
6728 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6730 /* Note that we do not substitute into default arguments here. The
6731 standard mandates that they be instantiated only when needed,
6732 which is done in build_over_call. */
6733 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6734 remaining_arg_types);
6738 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6739 *not* handle the exception-specification for FNTYPE, because the
6740 initial substitution of explicitly provided template parameters
6741 during argument deduction forbids substitution into the
6742 exception-specification:
6746 All references in the function type of the function template to the
6747 corresponding template parameters are replaced by the specified tem-
6748 plate argument values. If a substitution in a template parameter or
6749 in the function type of the function template results in an invalid
6750 type, type deduction fails. [Note: The equivalent substitution in
6751 exception specifications is done only when the function is instanti-
6752 ated, at which point a program is ill-formed if the substitution
6753 results in an invalid type.] */
6756 tsubst_function_type (tree t,
6758 tsubst_flags_t complain,
6765 /* The TYPE_CONTEXT is not used for function/method types. */
6766 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6768 /* Substitute the return type. */
6769 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6770 if (return_type == error_mark_node)
6771 return error_mark_node;
6772 /* The standard does not presently indicate that creation of a
6773 function type with an invalid return type is a deduction failure.
6774 However, that is clearly analogous to creating an array of "void"
6775 or a reference to a reference. This is core issue #486. */
6776 if (TREE_CODE (return_type) == ARRAY_TYPE
6777 || TREE_CODE (return_type) == FUNCTION_TYPE)
6779 if (complain & tf_error)
6781 if (TREE_CODE (return_type) == ARRAY_TYPE)
6782 error ("function returning an array");
6784 error ("function returning a function");
6786 return error_mark_node;
6789 /* Substitute the argument types. */
6790 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6792 if (arg_types == error_mark_node)
6793 return error_mark_node;
6795 /* Construct a new type node and return it. */
6796 if (TREE_CODE (t) == FUNCTION_TYPE)
6797 fntype = build_function_type (return_type, arg_types);
6800 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6801 if (! IS_AGGR_TYPE (r))
6805 Type deduction may fail for any of the following
6808 -- Attempting to create "pointer to member of T" when T
6809 is not a class type. */
6810 if (complain & tf_error)
6811 error ("creating pointer to member function of non-class type %qT",
6813 return error_mark_node;
6816 fntype = build_method_type_directly (r, return_type,
6817 TREE_CHAIN (arg_types));
6819 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6820 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6825 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6826 ARGS into that specification, and return the substituted
6827 specification. If there is no specification, return NULL_TREE. */
6830 tsubst_exception_specification (tree fntype,
6832 tsubst_flags_t complain,
6838 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6839 new_specs = NULL_TREE;
6842 if (! TREE_VALUE (specs))
6848 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6849 if (spec == error_mark_node)
6851 new_specs = add_exception_specifier (new_specs, spec, complain);
6852 specs = TREE_CHAIN (specs);
6858 /* Substitute into the PARMS of a call-declarator. */
6861 tsubst_call_declarator_parms (tree parms,
6863 tsubst_flags_t complain,
6870 if (!parms || parms == void_list_node)
6873 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6874 args, complain, in_decl);
6876 /* Figure out the type of this parameter. */
6877 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6879 /* Figure out the default argument as well. Note that we use
6880 tsubst_expr since the default argument is really an expression. */
6881 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6883 /* Chain this parameter on to the front of those we have already
6884 processed. We don't use hash_tree_cons because that function
6885 doesn't check TREE_PARMLIST. */
6886 new_parms = tree_cons (defarg, type, new_parms);
6891 /* Take the tree structure T and replace template parameters used
6892 therein with the argument vector ARGS. IN_DECL is an associated
6893 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6894 Issue error and warning messages under control of COMPLAIN. Note
6895 that we must be relatively non-tolerant of extensions here, in
6896 order to preserve conformance; if we allow substitutions that
6897 should not be allowed, we may allow argument deductions that should
6898 not succeed, and therefore report ambiguous overload situations
6899 where there are none. In theory, we could allow the substitution,
6900 but indicate that it should have failed, and allow our caller to
6901 make sure that the right thing happens, but we don't try to do this
6904 This function is used for dealing with types, decls and the like;
6905 for expressions, use tsubst_expr or tsubst_copy. */
6908 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6912 if (t == NULL_TREE || t == error_mark_node
6913 || t == integer_type_node
6914 || t == void_type_node
6915 || t == char_type_node
6916 || t == unknown_type_node
6917 || TREE_CODE (t) == NAMESPACE_DECL)
6921 return tsubst_decl (t, args, complain);
6923 if (TREE_CODE (t) == IDENTIFIER_NODE)
6924 type = IDENTIFIER_TYPE_VALUE (t);
6926 type = TREE_TYPE (t);
6928 gcc_assert (type != unknown_type_node);
6931 && TREE_CODE (t) != TYPENAME_TYPE
6932 && TREE_CODE (t) != IDENTIFIER_NODE
6933 && TREE_CODE (t) != FUNCTION_TYPE
6934 && TREE_CODE (t) != METHOD_TYPE)
6935 type = tsubst (type, args, complain, in_decl);
6936 if (type == error_mark_node)
6937 return error_mark_node;
6939 switch (TREE_CODE (t))
6944 return tsubst_aggr_type (t, args, complain, in_decl,
6945 /*entering_scope=*/0);
6948 case IDENTIFIER_NODE:
6960 if (t == integer_type_node)
6963 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6964 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6968 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6970 /* The array dimension behaves like a non-type template arg,
6971 in that we want to fold it as much as possible. */
6972 max = tsubst_template_arg (omax, args, complain, in_decl);
6973 max = fold_decl_constant_value (max);
6975 if (integer_zerop (omax))
6977 /* Still allow an explicit array of size zero. */
6979 pedwarn ("creating array with size zero");
6981 else if (integer_zerop (max)
6982 || (TREE_CODE (max) == INTEGER_CST
6983 && INT_CST_LT (max, integer_zero_node)))
6987 Type deduction may fail for any of the following
6990 Attempting to create an array with a size that is
6991 zero or negative. */
6992 if (complain & tf_error)
6993 error ("creating array with size zero (%qE)", max);
6995 return error_mark_node;
6998 return compute_array_index_type (NULL_TREE, max);
7001 case TEMPLATE_TYPE_PARM:
7002 case TEMPLATE_TEMPLATE_PARM:
7003 case BOUND_TEMPLATE_TEMPLATE_PARM:
7004 case TEMPLATE_PARM_INDEX:
7009 tree arg = NULL_TREE;
7013 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7014 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7015 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7016 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7018 idx = TEMPLATE_TYPE_IDX (t);
7019 level = TEMPLATE_TYPE_LEVEL (t);
7023 idx = TEMPLATE_PARM_IDX (t);
7024 level = TEMPLATE_PARM_LEVEL (t);
7027 levels = TMPL_ARGS_DEPTH (args);
7028 if (level <= levels)
7029 arg = TMPL_ARG (args, level, idx);
7031 if (arg == error_mark_node)
7032 return error_mark_node;
7033 else if (arg != NULL_TREE)
7035 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7037 gcc_assert (TYPE_P (arg));
7038 return cp_build_qualified_type_real
7039 (arg, cp_type_quals (arg) | cp_type_quals (t),
7040 complain | tf_ignore_bad_quals);
7042 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7044 /* We are processing a type constructed from a
7045 template template parameter. */
7046 tree argvec = tsubst (TYPE_TI_ARGS (t),
7047 args, complain, in_decl);
7048 if (argvec == error_mark_node)
7049 return error_mark_node;
7051 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7052 are resolving nested-types in the signature of a
7053 member function templates. Otherwise ARG is a
7054 TEMPLATE_DECL and is the real template to be
7056 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7057 arg = TYPE_NAME (arg);
7059 r = lookup_template_class (arg,
7062 /*entering_scope=*/0,
7064 return cp_build_qualified_type_real
7065 (r, TYPE_QUALS (t), complain);
7068 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7073 /* This can happen during the attempted tsubst'ing in
7074 unify. This means that we don't yet have any information
7075 about the template parameter in question. */
7078 /* If we get here, we must have been looking at a parm for a
7079 more deeply nested template. Make a new version of this
7080 template parameter, but with a lower level. */
7081 switch (TREE_CODE (t))
7083 case TEMPLATE_TYPE_PARM:
7084 case TEMPLATE_TEMPLATE_PARM:
7085 case BOUND_TEMPLATE_TEMPLATE_PARM:
7086 if (cp_type_quals (t))
7088 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7089 r = cp_build_qualified_type_real
7090 (r, cp_type_quals (t),
7091 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7092 ? tf_ignore_bad_quals : 0));
7097 TEMPLATE_TYPE_PARM_INDEX (r)
7098 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7100 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7101 TYPE_MAIN_VARIANT (r) = r;
7102 TYPE_POINTER_TO (r) = NULL_TREE;
7103 TYPE_REFERENCE_TO (r) = NULL_TREE;
7105 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7107 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7109 if (argvec == error_mark_node)
7110 return error_mark_node;
7112 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7113 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7118 case TEMPLATE_PARM_INDEX:
7119 r = reduce_template_parm_level (t, type, levels);
7131 tree purpose, value, chain;
7133 if (t == void_list_node)
7136 purpose = TREE_PURPOSE (t);
7139 purpose = tsubst (purpose, args, complain, in_decl);
7140 if (purpose == error_mark_node)
7141 return error_mark_node;
7143 value = TREE_VALUE (t);
7146 value = tsubst (value, args, complain, in_decl);
7147 if (value == error_mark_node)
7148 return error_mark_node;
7150 chain = TREE_CHAIN (t);
7151 if (chain && chain != void_type_node)
7153 chain = tsubst (chain, args, complain, in_decl);
7154 if (chain == error_mark_node)
7155 return error_mark_node;
7157 if (purpose == TREE_PURPOSE (t)
7158 && value == TREE_VALUE (t)
7159 && chain == TREE_CHAIN (t))
7161 return hash_tree_cons (purpose, value, chain);
7165 /* We should never be tsubsting a binfo. */
7169 /* A vector of template arguments. */
7171 return tsubst_template_args (t, args, complain, in_decl);
7174 case REFERENCE_TYPE:
7176 enum tree_code code;
7178 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7181 code = TREE_CODE (t);
7186 Type deduction may fail for any of the following
7189 -- Attempting to create a pointer to reference type.
7190 -- Attempting to create a reference to a reference type or
7191 a reference to void. */
7192 if (TREE_CODE (type) == REFERENCE_TYPE
7193 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7195 static location_t last_loc;
7197 /* We keep track of the last time we issued this error
7198 message to avoid spewing a ton of messages during a
7199 single bad template instantiation. */
7200 if (complain & tf_error
7201 #ifdef USE_MAPPED_LOCATION
7202 && last_loc != input_location
7204 && (last_loc.line != input_line
7205 || last_loc.file != input_filename)
7209 if (TREE_CODE (type) == VOID_TYPE)
7210 error ("forming reference to void");
7212 error ("forming %s to reference type %qT",
7213 (code == POINTER_TYPE) ? "pointer" : "reference",
7215 last_loc = input_location;
7218 return error_mark_node;
7220 else if (code == POINTER_TYPE)
7222 r = build_pointer_type (type);
7223 if (TREE_CODE (type) == METHOD_TYPE)
7224 r = build_ptrmemfunc_type (r);
7227 r = build_reference_type (type);
7228 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7230 if (r != error_mark_node)
7231 /* Will this ever be needed for TYPE_..._TO values? */
7238 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7239 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7243 Type deduction may fail for any of the following
7246 -- Attempting to create "pointer to member of T" when T
7247 is not a class type. */
7248 if (complain & tf_error)
7249 error ("creating pointer to member of non-class type %qT", r);
7250 return error_mark_node;
7252 if (TREE_CODE (type) == REFERENCE_TYPE)
7254 if (complain & tf_error)
7255 error ("creating pointer to member reference type %qT", type);
7257 return error_mark_node;
7259 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7260 if (TREE_CODE (type) == FUNCTION_TYPE)
7262 /* This is really a method type. The cv qualifiers of the
7263 this pointer should _not_ be determined by the cv
7264 qualifiers of the class type. They should be held
7265 somewhere in the FUNCTION_TYPE, but we don't do that at
7266 the moment. Consider
7267 typedef void (Func) () const;
7269 template <typename T1> void Foo (Func T1::*);
7274 method_type = build_method_type_directly (TYPE_MAIN_VARIANT (r),
7276 TYPE_ARG_TYPES (type));
7277 return build_ptrmemfunc_type (build_pointer_type (method_type));
7280 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7289 fntype = tsubst_function_type (t, args, complain, in_decl);
7290 if (fntype == error_mark_node)
7291 return error_mark_node;
7293 /* Substitute the exception specification. */
7294 specs = tsubst_exception_specification (t, args, complain,
7297 fntype = build_exception_variant (fntype, specs);
7302 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7303 if (domain == error_mark_node)
7304 return error_mark_node;
7306 /* As an optimization, we avoid regenerating the array type if
7307 it will obviously be the same as T. */
7308 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7311 /* These checks should match the ones in grokdeclarator.
7315 The deduction may fail for any of the following reasons:
7317 -- Attempting to create an array with an element type that
7318 is void, a function type, or a reference type, or [DR337]
7319 an abstract class type. */
7320 if (TREE_CODE (type) == VOID_TYPE
7321 || TREE_CODE (type) == FUNCTION_TYPE
7322 || TREE_CODE (type) == REFERENCE_TYPE)
7324 if (complain & tf_error)
7325 error ("creating array of %qT", type);
7326 return error_mark_node;
7328 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7330 if (complain & tf_error)
7331 error ("creating array of %qT, which is an abstract class type",
7333 return error_mark_node;
7336 r = build_cplus_array_type (type, domain);
7343 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7344 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7346 if (e1 == error_mark_node || e2 == error_mark_node)
7347 return error_mark_node;
7349 return fold (build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2));
7355 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7356 if (e == error_mark_node)
7357 return error_mark_node;
7359 return fold (build1 (TREE_CODE (t), TREE_TYPE (t), e));
7364 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7365 in_decl, /*entering_scope=*/1);
7366 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7369 if (ctx == error_mark_node || f == error_mark_node)
7370 return error_mark_node;
7372 if (!IS_AGGR_TYPE (ctx))
7374 if (complain & tf_error)
7375 error ("%qT is not a class, struct, or union type", ctx);
7376 return error_mark_node;
7378 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7380 /* Normally, make_typename_type does not require that the CTX
7381 have complete type in order to allow things like:
7383 template <class T> struct S { typename S<T>::X Y; };
7385 But, such constructs have already been resolved by this
7386 point, so here CTX really should have complete type, unless
7387 it's a partial instantiation. */
7388 ctx = complete_type (ctx);
7389 if (!COMPLETE_TYPE_P (ctx))
7391 if (complain & tf_error)
7392 cxx_incomplete_type_error (NULL_TREE, ctx);
7393 return error_mark_node;
7397 f = make_typename_type (ctx, f, typename_type,
7398 (complain & tf_error) | tf_keep_type_decl);
7399 if (f == error_mark_node)
7401 if (TREE_CODE (f) == TYPE_DECL)
7403 complain |= tf_ignore_bad_quals;
7407 if (TREE_CODE (f) != TYPENAME_TYPE)
7409 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7410 error ("%qT resolves to %qT, which is not an enumeration type",
7412 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7413 error ("%qT resolves to %qT, which is is not a class type",
7417 return cp_build_qualified_type_real
7418 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7421 case UNBOUND_CLASS_TEMPLATE:
7423 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7424 in_decl, /*entering_scope=*/1);
7425 tree name = TYPE_IDENTIFIER (t);
7426 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7428 if (ctx == error_mark_node || name == error_mark_node)
7429 return error_mark_node;
7432 parm_list = tsubst_template_parms (parm_list, args, complain);
7433 return make_unbound_class_template (ctx, name, parm_list, complain);
7443 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7444 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7445 if (e1 == error_mark_node || e2 == error_mark_node)
7446 return error_mark_node;
7448 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7453 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7454 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7455 if (e1 == error_mark_node || e2 == error_mark_node)
7456 return error_mark_node;
7458 return build_nt (TREE_CODE (t), e1, e2);
7465 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7466 complain, in_decl));
7467 return cp_build_qualified_type_real (type,
7469 | cp_type_quals (type),
7474 sorry ("use of %qs in template",
7475 tree_code_name [(int) TREE_CODE (t)]);
7476 return error_mark_node;
7480 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7481 type of the expression on the left-hand side of the "." or "->"
7485 tsubst_baselink (tree baselink, tree object_type,
7486 tree args, tsubst_flags_t complain, tree in_decl)
7489 tree qualifying_scope;
7491 tree template_args = 0;
7492 bool template_id_p = false;
7494 /* A baselink indicates a function from a base class. The
7495 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7496 non-dependent types; otherwise, the lookup could not have
7497 succeeded. However, they may indicate bases of the template
7498 class, rather than the instantiated class.
7500 In addition, lookups that were not ambiguous before may be
7501 ambiguous now. Therefore, we perform the lookup again. */
7502 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7503 fns = BASELINK_FUNCTIONS (baselink);
7504 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7506 template_id_p = true;
7507 template_args = TREE_OPERAND (fns, 1);
7508 fns = TREE_OPERAND (fns, 0);
7510 template_args = tsubst_template_args (template_args, args,
7513 name = DECL_NAME (get_first_fn (fns));
7514 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7516 /* If lookup found a single function, mark it as used at this
7517 point. (If it lookup found multiple functions the one selected
7518 later by overload resolution will be marked as used at that
7520 if (BASELINK_P (baselink))
7521 fns = BASELINK_FUNCTIONS (baselink);
7522 if (!template_id_p && !really_overloaded_fn (fns))
7523 mark_used (OVL_CURRENT (fns));
7525 /* Add back the template arguments, if present. */
7526 if (BASELINK_P (baselink) && template_id_p)
7527 BASELINK_FUNCTIONS (baselink)
7528 = build_nt (TEMPLATE_ID_EXPR,
7529 BASELINK_FUNCTIONS (baselink),
7533 object_type = current_class_type;
7534 return adjust_result_of_qualified_name_lookup (baselink,
7539 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7540 true if the qualified-id will be a postfix-expression in-and-of
7541 itself; false if more of the postfix-expression follows the
7542 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7546 tsubst_qualified_id (tree qualified_id, tree args,
7547 tsubst_flags_t complain, tree in_decl,
7548 bool done, bool address_p)
7556 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7558 /* Figure out what name to look up. */
7559 name = TREE_OPERAND (qualified_id, 1);
7560 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7563 template_args = TREE_OPERAND (name, 1);
7565 template_args = tsubst_template_args (template_args, args,
7567 name = TREE_OPERAND (name, 0);
7571 is_template = false;
7572 template_args = NULL_TREE;
7575 /* Substitute into the qualifying scope. When there are no ARGS, we
7576 are just trying to simplify a non-dependent expression. In that
7577 case the qualifying scope may be dependent, and, in any case,
7578 substituting will not help. */
7579 scope = TREE_OPERAND (qualified_id, 0);
7582 scope = tsubst (scope, args, complain, in_decl);
7583 expr = tsubst_copy (name, args, complain, in_decl);
7588 if (dependent_type_p (scope))
7589 return build_nt (SCOPE_REF, scope, expr);
7591 if (!BASELINK_P (name) && !DECL_P (expr))
7593 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7594 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7595 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7597 if (complain & tf_error)
7599 error ("dependent-name %qE is parsed as a non-type, but "
7600 "instantiation yields a type", qualified_id);
7601 inform ("say %<typename %E%> if a type is meant", qualified_id);
7603 return error_mark_node;
7609 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7611 /* Remember that there was a reference to this entity. */
7615 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7617 if (complain & tf_error)
7618 qualified_name_lookup_error (scope,
7619 TREE_OPERAND (qualified_id, 1),
7621 return error_mark_node;
7625 expr = lookup_template_function (expr, template_args);
7627 if (expr == error_mark_node && complain & tf_error)
7628 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7630 else if (TYPE_P (scope))
7632 expr = (adjust_result_of_qualified_name_lookup
7633 (expr, scope, current_class_type));
7634 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7637 expr = convert_from_reference (expr);
7642 /* Like tsubst, but deals with expressions. This function just replaces
7643 template parms; to finish processing the resultant expression, use
7647 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7649 enum tree_code code;
7652 if (t == NULL_TREE || t == error_mark_node)
7655 code = TREE_CODE (t);
7660 r = retrieve_local_specialization (t);
7661 gcc_assert (r != NULL);
7670 if (DECL_TEMPLATE_PARM_P (t))
7671 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7672 /* There is no need to substitute into namespace-scope
7674 if (DECL_NAMESPACE_SCOPE_P (t))
7676 /* If ARGS is NULL, then T is known to be non-dependent. */
7677 if (args == NULL_TREE)
7678 return integral_constant_value (t);
7680 /* Unfortunately, we cannot just call lookup_name here.
7683 template <int I> int f() {
7685 struct S { void g() { E e = a; } };
7688 When we instantiate f<7>::S::g(), say, lookup_name is not
7689 clever enough to find f<7>::a. */
7691 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7692 /*entering_scope=*/0);
7694 for (v = TYPE_VALUES (enum_type);
7697 if (TREE_PURPOSE (v) == DECL_NAME (t))
7698 return TREE_VALUE (v);
7700 /* We didn't find the name. That should never happen; if
7701 name-lookup found it during preliminary parsing, we
7702 should find it again here during instantiation. */
7708 if (DECL_CONTEXT (t))
7712 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7713 /*entering_scope=*/1);
7714 if (ctx != DECL_CONTEXT (t))
7716 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7719 if (complain & tf_error)
7720 error ("using invalid field %qD", t);
7721 return error_mark_node;
7731 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7732 || local_variable_p (t))
7733 t = tsubst (t, args, complain, in_decl);
7738 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7741 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7742 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7743 args, complain, in_decl);
7744 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7745 return tsubst (t, args, complain, in_decl);
7746 else if (DECL_CLASS_SCOPE_P (t)
7747 && uses_template_parms (DECL_CONTEXT (t)))
7749 /* Template template argument like the following example need
7752 template <template <class> class TT> struct C {};
7753 template <class T> struct D {
7754 template <class U> struct E {};
7759 We are processing the template argument `E' in #1 for
7760 the template instantiation #2. Originally, `E' is a
7761 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7762 have to substitute this with one having context `D<int>'. */
7764 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7765 return lookup_field (context, DECL_NAME(t), 0, false);
7768 /* Ordinary template template argument. */
7772 case REINTERPRET_CAST_EXPR:
7773 case CONST_CAST_EXPR:
7774 case STATIC_CAST_EXPR:
7775 case DYNAMIC_CAST_EXPR:
7778 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7779 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7783 case TRUTH_NOT_EXPR:
7786 case CONVERT_EXPR: /* Unary + */
7795 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7796 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7803 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7804 name = TREE_OPERAND (t, 1);
7805 if (TREE_CODE (name) == BIT_NOT_EXPR)
7807 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7809 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7811 else if (TREE_CODE (name) == SCOPE_REF
7812 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7814 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7816 name = TREE_OPERAND (name, 1);
7817 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7819 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7820 name = build_nt (SCOPE_REF, base, name);
7822 else if (TREE_CODE (name) == BASELINK)
7823 name = tsubst_baselink (name,
7824 non_reference (TREE_TYPE (object)),
7828 name = tsubst_copy (name, args, complain, in_decl);
7829 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7835 case TRUNC_DIV_EXPR:
7837 case FLOOR_DIV_EXPR:
7838 case ROUND_DIV_EXPR:
7839 case EXACT_DIV_EXPR:
7843 case TRUNC_MOD_EXPR:
7844 case FLOOR_MOD_EXPR:
7845 case TRUTH_ANDIF_EXPR:
7846 case TRUTH_ORIF_EXPR:
7847 case TRUTH_AND_EXPR:
7865 case PREDECREMENT_EXPR:
7866 case PREINCREMENT_EXPR:
7867 case POSTDECREMENT_EXPR:
7868 case POSTINCREMENT_EXPR:
7870 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7871 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7876 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7877 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7878 NULL_TREE, NULL_TREE);
7881 return build_nt (code,
7882 tsubst_copy (TREE_OPERAND (t, 0), args,
7884 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7890 case PSEUDO_DTOR_EXPR:
7893 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7894 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7895 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7896 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7903 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7904 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7905 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7906 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7913 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7914 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7915 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7916 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7920 case TEMPLATE_ID_EXPR:
7922 /* Substituted template arguments */
7923 tree fn = TREE_OPERAND (t, 0);
7924 tree targs = TREE_OPERAND (t, 1);
7926 fn = tsubst_copy (fn, args, complain, in_decl);
7928 targs = tsubst_template_args (targs, args, complain, in_decl);
7930 return lookup_template_function (fn, targs);
7935 tree purpose, value, chain;
7937 if (t == void_list_node)
7940 purpose = TREE_PURPOSE (t);
7942 purpose = tsubst_copy (purpose, args, complain, in_decl);
7943 value = TREE_VALUE (t);
7945 value = tsubst_copy (value, args, complain, in_decl);
7946 chain = TREE_CHAIN (t);
7947 if (chain && chain != void_type_node)
7948 chain = tsubst_copy (chain, args, complain, in_decl);
7949 if (purpose == TREE_PURPOSE (t)
7950 && value == TREE_VALUE (t)
7951 && chain == TREE_CHAIN (t))
7953 return tree_cons (purpose, value, chain);
7960 case TEMPLATE_TYPE_PARM:
7961 case TEMPLATE_TEMPLATE_PARM:
7962 case BOUND_TEMPLATE_TEMPLATE_PARM:
7963 case TEMPLATE_PARM_INDEX:
7965 case REFERENCE_TYPE:
7971 case UNBOUND_CLASS_TEMPLATE:
7974 return tsubst (t, args, complain, in_decl);
7976 case IDENTIFIER_NODE:
7977 if (IDENTIFIER_TYPENAME_P (t))
7979 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7980 return mangle_conv_op_name_for_type (new_type);
7987 r = build_constructor
7988 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7989 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7990 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7995 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7997 tsubst (TREE_TYPE (t), args, complain, in_decl));
7999 case CLEANUP_POINT_EXPR:
8000 /* We shouldn't have built any of these during initial template
8001 generation. Instead, they should be built during instantiation
8002 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8010 /* Like tsubst_copy for expressions, etc. but also does semantic
8014 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8018 if (t == NULL_TREE || t == error_mark_node)
8021 if (EXPR_HAS_LOCATION (t))
8022 input_location = EXPR_LOCATION (t);
8023 if (STATEMENT_CODE_P (TREE_CODE (t)))
8024 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8026 switch (TREE_CODE (t))
8028 case STATEMENT_LIST:
8030 tree_stmt_iterator i;
8031 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8032 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8036 case CTOR_INITIALIZER:
8037 finish_mem_initializers (tsubst_initializer_list
8038 (TREE_OPERAND (t, 0), args));
8042 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8043 args, complain, in_decl));
8047 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8048 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8049 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8051 finish_expr_stmt (tmp);
8055 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8056 args, complain, in_decl));
8064 decl = DECL_EXPR_DECL (t);
8065 if (TREE_CODE (decl) == LABEL_DECL)
8066 finish_label_decl (DECL_NAME (decl));
8067 else if (TREE_CODE (decl) == USING_DECL)
8069 tree scope = DECL_INITIAL (decl);
8070 tree name = DECL_NAME (decl);
8073 scope = tsubst_expr (scope, args, complain, in_decl);
8074 decl = lookup_qualified_name (scope, name,
8075 /*is_type_p=*/false,
8076 /*complain=*/false);
8077 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8078 qualified_name_lookup_error (scope, name, decl);
8080 do_local_using_decl (decl, scope, name);
8084 init = DECL_INITIAL (decl);
8085 decl = tsubst (decl, args, complain, in_decl);
8086 if (decl != error_mark_node)
8089 DECL_INITIAL (decl) = error_mark_node;
8090 /* By marking the declaration as instantiated, we avoid
8091 trying to instantiate it. Since instantiate_decl can't
8092 handle local variables, and since we've already done
8093 all that needs to be done, that's the right thing to
8095 if (TREE_CODE (decl) == VAR_DECL)
8096 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8097 if (TREE_CODE (decl) == VAR_DECL
8098 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8099 /* Anonymous aggregates are a special case. */
8100 finish_anon_union (decl);
8103 maybe_push_decl (decl);
8104 if (TREE_CODE (decl) == VAR_DECL
8105 && DECL_PRETTY_FUNCTION_P (decl))
8107 /* For __PRETTY_FUNCTION__ we have to adjust the
8109 const char *const name
8110 = cxx_printable_name (current_function_decl, 2);
8111 init = cp_fname_init (name, &TREE_TYPE (decl));
8114 init = tsubst_expr (init, args, complain, in_decl);
8115 cp_finish_decl (decl, init, NULL_TREE, 0);
8120 /* A DECL_EXPR can also be used as an expression, in the condition
8121 clause of an if/for/while construct. */
8126 stmt = begin_for_stmt ();
8127 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8128 finish_for_init_stmt (stmt);
8129 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8130 finish_for_cond (tmp, stmt);
8131 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8132 finish_for_expr (tmp, stmt);
8133 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8134 finish_for_stmt (stmt);
8138 stmt = begin_while_stmt ();
8139 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8140 finish_while_stmt_cond (tmp, stmt);
8141 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8142 finish_while_stmt (stmt);
8146 stmt = begin_do_stmt ();
8147 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8148 finish_do_body (stmt);
8149 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8150 finish_do_stmt (tmp, stmt);
8154 stmt = begin_if_stmt ();
8155 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8156 finish_if_stmt_cond (tmp, stmt);
8157 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8158 finish_then_clause (stmt);
8160 if (ELSE_CLAUSE (t))
8162 begin_else_clause (stmt);
8163 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8164 finish_else_clause (stmt);
8167 finish_if_stmt (stmt);
8171 if (BIND_EXPR_BODY_BLOCK (t))
8172 stmt = begin_function_body ();
8174 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8175 ? BCS_TRY_BLOCK : 0);
8177 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8179 if (BIND_EXPR_BODY_BLOCK (t))
8180 finish_function_body (stmt);
8182 finish_compound_stmt (stmt);
8186 finish_break_stmt ();
8190 finish_continue_stmt ();
8194 stmt = begin_switch_stmt ();
8195 tmp = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
8196 finish_switch_cond (tmp, stmt);
8197 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
8198 finish_switch_stmt (stmt);
8201 case CASE_LABEL_EXPR:
8202 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8203 tsubst_expr (CASE_HIGH (t), args, complain,
8208 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8212 tmp = GOTO_DESTINATION (t);
8213 if (TREE_CODE (tmp) != LABEL_DECL)
8214 /* Computed goto's must be tsubst'd into. On the other hand,
8215 non-computed gotos must not be; the identifier in question
8216 will have no binding. */
8217 tmp = tsubst_expr (tmp, args, complain, in_decl);
8219 tmp = DECL_NAME (tmp);
8220 finish_goto_stmt (tmp);
8224 tmp = finish_asm_stmt
8225 (ASM_VOLATILE_P (t),
8226 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8227 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8228 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8229 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8231 tree asm_expr = tmp;
8232 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8233 asm_expr = TREE_OPERAND (asm_expr, 0);
8234 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8241 stmt = begin_try_block ();
8242 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8243 finish_cleanup_try_block (stmt);
8244 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8250 if (FN_TRY_BLOCK_P (t))
8251 stmt = begin_function_try_block ();
8253 stmt = begin_try_block ();
8255 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8257 if (FN_TRY_BLOCK_P (t))
8258 finish_function_try_block (stmt);
8260 finish_try_block (stmt);
8262 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8263 if (FN_TRY_BLOCK_P (t))
8264 finish_function_handler_sequence (stmt);
8266 finish_handler_sequence (stmt);
8274 stmt = begin_handler ();
8275 if (HANDLER_PARMS (t))
8277 decl = HANDLER_PARMS (t);
8278 decl = tsubst (decl, args, complain, in_decl);
8279 /* Prevent instantiate_decl from trying to instantiate
8280 this variable. We've already done all that needs to be
8282 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8286 finish_handler_parms (decl, stmt);
8287 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8288 finish_handler (stmt);
8293 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8297 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8299 return tsubst_copy_and_build (t, args, complain, in_decl,
8300 /*function_p=*/false);
8306 /* T is a postfix-expression that is not being used in a function
8307 call. Return the substituted version of T. */
8310 tsubst_non_call_postfix_expression (tree t, tree args,
8311 tsubst_flags_t complain,
8314 if (TREE_CODE (t) == SCOPE_REF)
8315 t = tsubst_qualified_id (t, args, complain, in_decl,
8316 /*done=*/false, /*address_p=*/false);
8318 t = tsubst_copy_and_build (t, args, complain, in_decl,
8319 /*function_p=*/false);
8324 /* Like tsubst but deals with expressions and performs semantic
8325 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8328 tsubst_copy_and_build (tree t,
8330 tsubst_flags_t complain,
8334 #define RECUR(NODE) \
8335 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8339 if (t == NULL_TREE || t == error_mark_node)
8342 switch (TREE_CODE (t))
8347 case IDENTIFIER_NODE:
8351 tree qualifying_class;
8352 bool non_integral_constant_expression_p;
8353 const char *error_msg;
8355 if (IDENTIFIER_TYPENAME_P (t))
8357 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8358 t = mangle_conv_op_name_for_type (new_type);
8361 /* Look up the name. */
8362 decl = lookup_name (t, 0);
8364 /* By convention, expressions use ERROR_MARK_NODE to indicate
8365 failure, not NULL_TREE. */
8366 if (decl == NULL_TREE)
8367 decl = error_mark_node;
8369 decl = finish_id_expression (t, decl, NULL_TREE,
8372 /*integral_constant_expression_p=*/false,
8373 /*allow_non_integral_constant_expression_p=*/false,
8374 &non_integral_constant_expression_p,
8378 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8379 decl = unqualified_name_lookup_error (decl);
8383 case TEMPLATE_ID_EXPR:
8386 tree template = RECUR (TREE_OPERAND (t, 0));
8387 tree targs = TREE_OPERAND (t, 1);
8390 targs = tsubst_template_args (targs, args, complain, in_decl);
8392 if (TREE_CODE (template) == COMPONENT_REF)
8394 object = TREE_OPERAND (template, 0);
8395 template = TREE_OPERAND (template, 1);
8399 template = lookup_template_function (template, targs);
8402 return build3 (COMPONENT_REF, TREE_TYPE (template),
8403 object, template, NULL_TREE);
8410 tree r = RECUR (TREE_OPERAND (t, 0));
8412 if (REFERENCE_REF_P (t))
8414 /* A type conversion to reference type will be enclosed in
8415 such an indirect ref, but the substitution of the cast
8416 will have also added such an indirect ref. */
8417 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8418 r = convert_from_reference (r);
8421 r = build_x_indirect_ref (r, "unary *");
8427 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8428 RECUR (TREE_OPERAND (t, 0)));
8431 return build_functional_cast
8432 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8433 RECUR (TREE_OPERAND (t, 0)));
8435 case REINTERPRET_CAST_EXPR:
8436 return build_reinterpret_cast
8437 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8438 RECUR (TREE_OPERAND (t, 0)));
8440 case CONST_CAST_EXPR:
8441 return build_const_cast
8442 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8443 RECUR (TREE_OPERAND (t, 0)));
8445 case DYNAMIC_CAST_EXPR:
8446 return build_dynamic_cast
8447 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8448 RECUR (TREE_OPERAND (t, 0)));
8450 case STATIC_CAST_EXPR:
8451 return build_static_cast
8452 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8453 RECUR (TREE_OPERAND (t, 0)));
8455 case POSTDECREMENT_EXPR:
8456 case POSTINCREMENT_EXPR:
8457 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8458 args, complain, in_decl);
8459 return build_x_unary_op (TREE_CODE (t), op1);
8461 case PREDECREMENT_EXPR:
8462 case PREINCREMENT_EXPR:
8466 case TRUTH_NOT_EXPR:
8467 case CONVERT_EXPR: /* Unary + */
8470 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8473 op1 = TREE_OPERAND (t, 0);
8474 if (TREE_CODE (op1) == SCOPE_REF)
8475 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8476 /*done=*/true, /*address_p=*/true);
8478 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8480 if (TREE_CODE (op1) == LABEL_DECL)
8481 return finish_label_address_expr (DECL_NAME (op1));
8482 return build_x_unary_op (ADDR_EXPR, op1);
8487 case TRUNC_DIV_EXPR:
8489 case FLOOR_DIV_EXPR:
8490 case ROUND_DIV_EXPR:
8491 case EXACT_DIV_EXPR:
8495 case TRUNC_MOD_EXPR:
8496 case FLOOR_MOD_EXPR:
8497 case TRUTH_ANDIF_EXPR:
8498 case TRUTH_ORIF_EXPR:
8499 case TRUTH_AND_EXPR:
8515 return build_x_binary_op
8517 RECUR (TREE_OPERAND (t, 0)),
8518 RECUR (TREE_OPERAND (t, 1)),
8519 /*overloaded_p=*/NULL);
8522 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8523 /*address_p=*/false);
8525 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8526 args, complain, in_decl);
8527 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8528 /*overloaded_p=*/NULL);
8532 op1 = TREE_OPERAND (t, 0);
8535 /* When there are no ARGS, we are trying to evaluate a
8536 non-dependent expression from the parser. Trying to do
8537 the substitutions may not work. */
8539 op1 = TREE_TYPE (op1);
8548 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8550 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8554 tree r = build_x_modify_expr
8555 (RECUR (TREE_OPERAND (t, 0)),
8556 TREE_CODE (TREE_OPERAND (t, 1)),
8557 RECUR (TREE_OPERAND (t, 2)));
8558 /* TREE_NO_WARNING must be set if either the expression was
8559 parenthesized or it uses an operator such as >>= rather
8560 than plain assignment. In the former case, it was already
8561 set and must be copied. In the latter case,
8562 build_x_modify_expr sets it and it must not be reset
8564 if (TREE_NO_WARNING (t))
8565 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8570 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8571 args, complain, in_decl);
8572 /* Remember that there was a reference to this entity. */
8575 return build_x_arrow (op1);
8579 (RECUR (TREE_OPERAND (t, 0)),
8580 RECUR (TREE_OPERAND (t, 1)),
8581 RECUR (TREE_OPERAND (t, 2)),
8582 RECUR (TREE_OPERAND (t, 3)),
8583 NEW_EXPR_USE_GLOBAL (t));
8586 return delete_sanity
8587 (RECUR (TREE_OPERAND (t, 0)),
8588 RECUR (TREE_OPERAND (t, 1)),
8589 DELETE_EXPR_USE_VEC (t),
8590 DELETE_EXPR_USE_GLOBAL (t));
8593 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8594 RECUR (TREE_OPERAND (t, 1)));
8603 function = TREE_OPERAND (t, 0);
8604 /* When we parsed the expression, we determined whether or
8605 not Koenig lookup should be performed. */
8606 koenig_p = KOENIG_LOOKUP_P (t);
8607 if (TREE_CODE (function) == SCOPE_REF)
8610 function = tsubst_qualified_id (function, args, complain, in_decl,
8612 /*address_p=*/false);
8616 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8617 && (TREE_CODE (TREE_OPERAND (function, 1))
8619 function = tsubst_copy_and_build (function, args, complain,
8622 if (BASELINK_P (function))
8626 call_args = RECUR (TREE_OPERAND (t, 1));
8628 /* We do not perform argument-dependent lookup if normal
8629 lookup finds a non-function, in accordance with the
8630 expected resolution of DR 218. */
8632 && ((is_overloaded_fn (function)
8633 /* If lookup found a member function, the Koenig lookup is
8634 not appropriate, even if an unqualified-name was used
8635 to denote the function. */
8636 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8637 || TREE_CODE (function) == IDENTIFIER_NODE))
8638 function = perform_koenig_lookup (function, call_args);
8640 if (TREE_CODE (function) == IDENTIFIER_NODE)
8642 unqualified_name_lookup_error (function);
8643 return error_mark_node;
8646 /* Remember that there was a reference to this entity. */
8647 if (DECL_P (function))
8648 mark_used (function);
8650 if (TREE_CODE (function) == OFFSET_REF)
8651 return build_offset_ref_call_from_tree (function, call_args);
8652 if (TREE_CODE (function) == COMPONENT_REF)
8654 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8655 return finish_call_expr (function, call_args,
8656 /*disallow_virtual=*/false,
8657 /*koenig_p=*/false);
8659 return (build_new_method_call
8660 (TREE_OPERAND (function, 0),
8661 TREE_OPERAND (function, 1),
8662 call_args, NULL_TREE,
8663 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8665 return finish_call_expr (function, call_args,
8666 /*disallow_virtual=*/qualified_p,
8671 return build_x_conditional_expr
8672 (RECUR (TREE_OPERAND (t, 0)),
8673 RECUR (TREE_OPERAND (t, 1)),
8674 RECUR (TREE_OPERAND (t, 2)));
8676 case PSEUDO_DTOR_EXPR:
8677 return finish_pseudo_destructor_expr
8678 (RECUR (TREE_OPERAND (t, 0)),
8679 RECUR (TREE_OPERAND (t, 1)),
8680 RECUR (TREE_OPERAND (t, 2)));
8684 tree purpose, value, chain;
8686 if (t == void_list_node)
8689 purpose = TREE_PURPOSE (t);
8691 purpose = RECUR (purpose);
8692 value = TREE_VALUE (t);
8694 value = RECUR (value);
8695 chain = TREE_CHAIN (t);
8696 if (chain && chain != void_type_node)
8697 chain = RECUR (chain);
8698 if (purpose == TREE_PURPOSE (t)
8699 && value == TREE_VALUE (t)
8700 && chain == TREE_CHAIN (t))
8702 return tree_cons (purpose, value, chain);
8710 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8711 args, complain, in_decl);
8712 /* Remember that there was a reference to this entity. */
8713 if (DECL_P (object))
8716 member = TREE_OPERAND (t, 1);
8717 if (BASELINK_P (member))
8718 member = tsubst_baselink (member,
8719 non_reference (TREE_TYPE (object)),
8720 args, complain, in_decl);
8722 member = tsubst_copy (member, args, complain, in_decl);
8724 if (member == error_mark_node)
8725 return error_mark_node;
8726 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8728 if (TREE_CODE (member) == BIT_NOT_EXPR)
8729 return finish_pseudo_destructor_expr (object,
8731 TREE_TYPE (object));
8732 else if (TREE_CODE (member) == SCOPE_REF
8733 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8734 return finish_pseudo_destructor_expr (object,
8736 TREE_TYPE (object));
8738 else if (TREE_CODE (member) == SCOPE_REF
8739 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8744 /* Lookup the template functions now that we know what the
8746 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8747 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8748 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8749 /*is_type_p=*/false,
8750 /*complain=*/false);
8751 if (BASELINK_P (member))
8753 BASELINK_FUNCTIONS (member)
8754 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8756 member = (adjust_result_of_qualified_name_lookup
8757 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8758 TREE_TYPE (object)));
8762 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8764 return error_mark_node;
8767 else if (TREE_CODE (member) == SCOPE_REF
8768 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8769 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8771 if (complain & tf_error)
8773 if (TYPE_P (TREE_OPERAND (member, 0)))
8774 error ("%qT is not a class or namespace",
8775 TREE_OPERAND (member, 0));
8777 error ("%qD is not a class or namespace",
8778 TREE_OPERAND (member, 0));
8780 return error_mark_node;
8782 else if (TREE_CODE (member) == FIELD_DECL)
8783 return finish_non_static_data_member (member, object, NULL_TREE);
8785 return finish_class_member_access_expr (object, member);
8790 (RECUR (TREE_OPERAND (t, 0)));
8796 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8799 /* digest_init will do the wrong thing if we let it. */
8800 if (type && TYPE_PTRMEMFUNC_P (type))
8804 /* We do not want to process the purpose of aggregate
8805 initializers as they are identifier nodes which will be
8806 looked up by digest_init. */
8807 purpose_p = !(type && IS_AGGR_TYPE (type));
8808 for (elts = CONSTRUCTOR_ELTS (t);
8810 elts = TREE_CHAIN (elts))
8812 tree purpose = TREE_PURPOSE (elts);
8813 tree value = TREE_VALUE (elts);
8815 if (purpose && purpose_p)
8816 purpose = RECUR (purpose);
8817 value = RECUR (value);
8818 r = tree_cons (purpose, value, r);
8821 r = build_constructor (NULL_TREE, nreverse (r));
8822 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8825 return digest_init (type, r, 0);
8831 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8832 if (TYPE_P (operand_0))
8833 return get_typeid (operand_0);
8834 return build_typeid (operand_0);
8844 tree r = tsubst_copy (t, args, complain, in_decl);
8846 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8847 /* If the original type was a reference, we'll be wrapped in
8848 the appropriate INDIRECT_REF. */
8849 r = convert_from_reference (r);
8854 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8855 tsubst_copy (TREE_TYPE (t), args, complain,
8859 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8863 tree old_stmt_expr = cur_stmt_expr;
8864 tree stmt_expr = begin_stmt_expr ();
8866 cur_stmt_expr = stmt_expr;
8867 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8868 stmt_expr = finish_stmt_expr (stmt_expr, false);
8869 cur_stmt_expr = old_stmt_expr;
8875 t = tsubst_copy (t, args, complain, in_decl);
8876 /* As in finish_id_expression, we resolve enumeration constants
8877 to their underlying values. */
8878 if (TREE_CODE (t) == CONST_DECL)
8879 return DECL_INITIAL (t);
8883 return tsubst_copy (t, args, complain, in_decl);
8889 /* Verify that the instantiated ARGS are valid. For type arguments,
8890 make sure that the type's linkage is ok. For non-type arguments,
8891 make sure they are constants if they are integral or enumerations.
8892 Emit an error under control of COMPLAIN, and return TRUE on error. */
8895 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8897 int ix, len = DECL_NTPARMS (tmpl);
8898 bool result = false;
8900 for (ix = 0; ix != len; ix++)
8902 tree t = TREE_VEC_ELT (args, ix);
8906 /* [basic.link]: A name with no linkage (notably, the name
8907 of a class or enumeration declared in a local scope)
8908 shall not be used to declare an entity with linkage.
8909 This implies that names with no linkage cannot be used as
8910 template arguments. */
8911 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8915 if (TYPE_ANONYMOUS_P (nt))
8916 error ("%qT uses anonymous type", t);
8918 error ("%qT uses local type %qT", t, nt);
8921 /* In order to avoid all sorts of complications, we do not
8922 allow variably-modified types as template arguments. */
8923 else if (variably_modified_type_p (t, NULL_TREE))
8925 if (complain & tf_error)
8926 error ("%qT is a variably modified type", t);
8930 /* A non-type argument of integral or enumerated type must be a
8932 else if (TREE_TYPE (t)
8933 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8934 && !TREE_CONSTANT (t))
8936 if (complain & tf_error)
8937 error ("integral expression %qE is not constant", t);
8941 if (result && complain & tf_error)
8942 error (" trying to instantiate %qD", tmpl);
8946 /* Instantiate the indicated variable or function template TMPL with
8947 the template arguments in TARG_PTR. */
8950 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8956 if (tmpl == error_mark_node)
8957 return error_mark_node;
8959 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
8961 /* If this function is a clone, handle it specially. */
8962 if (DECL_CLONED_FUNCTION_P (tmpl))
8967 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8969 if (spec == error_mark_node)
8970 return error_mark_node;
8972 /* Look for the clone. */
8973 FOR_EACH_CLONE (clone, spec)
8974 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8976 /* We should always have found the clone by now. */
8981 /* Check to see if we already have this specialization. */
8982 spec = retrieve_specialization (tmpl, targ_ptr,
8983 /*class_specializations_p=*/false);
8984 if (spec != NULL_TREE)
8987 gen_tmpl = most_general_template (tmpl);
8988 if (tmpl != gen_tmpl)
8990 /* The TMPL is a partial instantiation. To get a full set of
8991 arguments we must add the arguments used to perform the
8992 partial instantiation. */
8993 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
8996 /* Check to see if we already have this specialization. */
8997 spec = retrieve_specialization (gen_tmpl, targ_ptr,
8998 /*class_specializations_p=*/false);
8999 if (spec != NULL_TREE)
9003 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9005 return error_mark_node;
9007 /* We are building a FUNCTION_DECL, during which the access of its
9008 parameters and return types have to be checked. However this
9009 FUNCTION_DECL which is the desired context for access checking
9010 is not built yet. We solve this chicken-and-egg problem by
9011 deferring all checks until we have the FUNCTION_DECL. */
9012 push_deferring_access_checks (dk_deferred);
9014 /* Substitute template parameters. */
9015 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9016 targ_ptr, complain, gen_tmpl);
9018 /* Now we know the specialization, compute access previously
9020 push_access_scope (fndecl);
9021 perform_deferred_access_checks ();
9022 pop_access_scope (fndecl);
9023 pop_deferring_access_checks ();
9025 /* The DECL_TI_TEMPLATE should always be the immediate parent
9026 template, not the most general template. */
9027 DECL_TI_TEMPLATE (fndecl) = tmpl;
9029 /* If we've just instantiated the main entry point for a function,
9030 instantiate all the alternate entry points as well. We do this
9031 by cloning the instantiation of the main entry point, not by
9032 instantiating the template clones. */
9033 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9034 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9039 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9040 arguments that are being used when calling it. TARGS is a vector
9041 into which the deduced template arguments are placed.
9043 Return zero for success, 2 for an incomplete match that doesn't resolve
9044 all the types, and 1 for complete failure. An error message will be
9045 printed only for an incomplete match.
9047 If FN is a conversion operator, or we are trying to produce a specific
9048 specialization, RETURN_TYPE is the return type desired.
9050 The EXPLICIT_TARGS are explicit template arguments provided via a
9053 The parameter STRICT is one of:
9056 We are deducing arguments for a function call, as in
9060 We are deducing arguments for a conversion function, as in
9064 We are deducing arguments when doing an explicit instantiation
9065 as in [temp.explicit], when determining an explicit specialization
9066 as in [temp.expl.spec], or when taking the address of a function
9067 template, as in [temp.deduct.funcaddr].
9070 We are deducing arguments when calculating the partial
9071 ordering between specializations of function or class
9072 templates, as in [temp.func.order] and [temp.class.order].
9074 LEN is the number of parms to consider before returning success, or -1
9075 for all. This is used in partial ordering to avoid comparing parms for
9076 which no actual argument was passed, since they are not considered in
9077 overload resolution (and are explicitly excluded from consideration in
9078 partial ordering in [temp.func.order]/6). */
9081 fn_type_unification (tree fn,
9082 tree explicit_targs,
9086 unification_kind_t strict,
9093 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9095 fntype = TREE_TYPE (fn);
9100 The specified template arguments must match the template
9101 parameters in kind (i.e., type, nontype, template), and there
9102 must not be more arguments than there are parameters;
9103 otherwise type deduction fails.
9105 Nontype arguments must match the types of the corresponding
9106 nontype template parameters, or must be convertible to the
9107 types of the corresponding nontype parameters as specified in
9108 _temp.arg.nontype_, otherwise type deduction fails.
9110 All references in the function type of the function template
9111 to the corresponding template parameters are replaced by the
9112 specified template argument values. If a substitution in a
9113 template parameter or in the function type of the function
9114 template results in an invalid type, type deduction fails. */
9116 tree converted_args;
9120 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9121 explicit_targs, NULL_TREE, tf_none,
9122 /*require_all_arguments=*/0));
9123 if (converted_args == error_mark_node)
9126 /* Substitute the explicit args into the function type. This is
9127 necessary so that, for instance, explicitly declared function
9128 arguments can match null pointed constants. If we were given
9129 an incomplete set of explicit args, we must not do semantic
9130 processing during substitution as we could create partial
9132 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9133 processing_template_decl += incomplete;
9134 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9135 processing_template_decl -= incomplete;
9137 if (fntype == error_mark_node)
9140 /* Place the explicitly specified arguments in TARGS. */
9141 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9142 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9145 parms = TYPE_ARG_TYPES (fntype);
9146 /* Never do unification on the 'this' parameter. */
9147 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9148 parms = TREE_CHAIN (parms);
9152 /* We've been given a return type to match, prepend it. */
9153 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9154 args = tree_cons (NULL_TREE, return_type, args);
9159 /* We allow incomplete unification without an error message here
9160 because the standard doesn't seem to explicitly prohibit it. Our
9161 callers must be ready to deal with unification failures in any
9163 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9164 targs, parms, args, /*subr=*/0,
9165 strict, /*allow_incomplete*/1, len);
9168 /* All is well so far. Now, check:
9172 When all template arguments have been deduced, all uses of
9173 template parameters in nondeduced contexts are replaced with
9174 the corresponding deduced argument values. If the
9175 substitution results in an invalid type, as described above,
9176 type deduction fails. */
9177 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9184 /* Adjust types before performing type deduction, as described in
9185 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9186 sections are symmetric. PARM is the type of a function parameter
9187 or the return type of the conversion function. ARG is the type of
9188 the argument passed to the call, or the type of the value
9189 initialized with the result of the conversion function. */
9192 maybe_adjust_types_for_deduction (unification_kind_t strict,
9205 /* Swap PARM and ARG throughout the remainder of this
9206 function; the handling is precisely symmetric since PARM
9207 will initialize ARG rather than vice versa. */
9215 /* There is nothing to do in this case. */
9219 /* DR 214. [temp.func.order] is underspecified, and leads to no
9220 ordering between things like `T *' and `T const &' for `U *'.
9221 The former has T=U and the latter T=U*. The former looks more
9222 specialized and John Spicer considers it well-formed (the EDG
9223 compiler accepts it).
9225 John also confirms that deduction should proceed as in a function
9226 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
9227 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
9228 to an actual call can have such a type.
9230 If both ARG and PARM are REFERENCE_TYPE, we change neither.
9231 If only ARG is a REFERENCE_TYPE, we look through that and then
9232 proceed as with DEDUCE_CALL (which could further convert it). */
9233 if (TREE_CODE (*arg) == REFERENCE_TYPE)
9235 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9237 *arg = TREE_TYPE (*arg);
9244 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9246 /* [temp.deduct.call]
9248 If P is not a reference type:
9250 --If A is an array type, the pointer type produced by the
9251 array-to-pointer standard conversion (_conv.array_) is
9252 used in place of A for type deduction; otherwise,
9254 --If A is a function type, the pointer type produced by
9255 the function-to-pointer standard conversion
9256 (_conv.func_) is used in place of A for type deduction;
9259 --If A is a cv-qualified type, the top level
9260 cv-qualifiers of A's type are ignored for type
9262 if (TREE_CODE (*arg) == ARRAY_TYPE)
9263 *arg = build_pointer_type (TREE_TYPE (*arg));
9264 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9265 *arg = build_pointer_type (*arg);
9267 *arg = TYPE_MAIN_VARIANT (*arg);
9270 /* [temp.deduct.call]
9272 If P is a cv-qualified type, the top level cv-qualifiers
9273 of P's type are ignored for type deduction. If P is a
9274 reference type, the type referred to by P is used for
9276 *parm = TYPE_MAIN_VARIANT (*parm);
9277 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9279 *parm = TREE_TYPE (*parm);
9280 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9283 /* DR 322. For conversion deduction, remove a reference type on parm
9284 too (which has been swapped into ARG). */
9285 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9286 *arg = TREE_TYPE (*arg);
9291 /* Most parms like fn_type_unification.
9293 If SUBR is 1, we're being called recursively (to unify the
9294 arguments of a function or method parameter of a function
9298 type_unification_real (tree tparms,
9303 unification_kind_t strict,
9304 int allow_incomplete,
9309 int ntparms = TREE_VEC_LENGTH (tparms);
9311 int saw_undeduced = 0;
9315 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9316 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9317 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9318 gcc_assert (ntparms > 0);
9323 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9324 | UNIFY_ALLOW_DERIVED);
9328 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9332 sub_strict = UNIFY_ALLOW_NONE;
9336 sub_strict = UNIFY_ALLOW_NONE;
9352 && parms != void_list_node
9354 && args != void_list_node)
9356 parm = TREE_VALUE (parms);
9357 parms = TREE_CHAIN (parms);
9358 arg = TREE_VALUE (args);
9359 args = TREE_CHAIN (args);
9361 if (arg == error_mark_node)
9363 if (arg == unknown_type_node)
9364 /* We can't deduce anything from this, but we might get all the
9365 template args from other function args. */
9368 /* Conversions will be performed on a function argument that
9369 corresponds with a function parameter that contains only
9370 non-deducible template parameters and explicitly specified
9371 template parameters. */
9372 if (!uses_template_parms (parm))
9377 type = TREE_TYPE (arg);
9381 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
9383 if (same_type_p (parm, type))
9387 /* It might work; we shouldn't check now, because we might
9388 get into infinite recursion. Overload resolution will
9397 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9398 if (type_unknown_p (arg))
9400 /* [temp.deduct.type] A template-argument can be deduced from
9401 a pointer to function or pointer to member function
9402 argument if the set of overloaded functions does not
9403 contain function templates and at most one of a set of
9404 overloaded functions provides a unique match. */
9406 if (resolve_overloaded_unification
9407 (tparms, targs, parm, arg, strict, sub_strict)
9412 arg = TREE_TYPE (arg);
9413 if (arg == error_mark_node)
9418 int arg_strict = sub_strict;
9421 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9423 if (unify (tparms, targs, parm, arg, arg_strict))
9427 /* Are we done with the interesting parms? */
9431 /* Fail if we've reached the end of the parm list, and more args
9432 are present, and the parm list isn't variadic. */
9433 if (args && args != void_list_node && parms == void_list_node)
9435 /* Fail if parms are left and they don't have default values. */
9437 && parms != void_list_node
9438 && TREE_PURPOSE (parms) == NULL_TREE)
9443 for (i = 0; i < ntparms; i++)
9444 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
9446 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9448 /* If this is an undeduced nontype parameter that depends on
9449 a type parameter, try another pass; its type may have been
9450 deduced from a later argument than the one from which
9451 this parameter can be deduced. */
9452 if (TREE_CODE (tparm) == PARM_DECL
9453 && uses_template_parms (TREE_TYPE (tparm))
9454 && !saw_undeduced++)
9457 if (!allow_incomplete)
9458 error ("incomplete type unification");
9464 /* Subroutine of type_unification_real. Args are like the variables at the
9465 call site. ARG is an overloaded function (or template-id); we try
9466 deducing template args from each of the overloads, and if only one
9467 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9470 resolve_overloaded_unification (tree tparms,
9474 unification_kind_t strict,
9477 tree tempargs = copy_node (targs);
9481 if (TREE_CODE (arg) == ADDR_EXPR)
9483 arg = TREE_OPERAND (arg, 0);
9489 if (TREE_CODE (arg) == COMPONENT_REF)
9490 /* Handle `&x' where `x' is some static or non-static member
9492 arg = TREE_OPERAND (arg, 1);
9494 if (TREE_CODE (arg) == OFFSET_REF)
9495 arg = TREE_OPERAND (arg, 1);
9497 /* Strip baselink information. */
9498 if (BASELINK_P (arg))
9499 arg = BASELINK_FUNCTIONS (arg);
9501 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9503 /* If we got some explicit template args, we need to plug them into
9504 the affected templates before we try to unify, in case the
9505 explicit args will completely resolve the templates in question. */
9507 tree expl_subargs = TREE_OPERAND (arg, 1);
9508 arg = TREE_OPERAND (arg, 0);
9510 for (; arg; arg = OVL_NEXT (arg))
9512 tree fn = OVL_CURRENT (arg);
9515 if (TREE_CODE (fn) != TEMPLATE_DECL)
9518 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
9522 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9523 good += try_one_overload (tparms, targs, tempargs, parm,
9524 elem, strict, sub_strict, addr_p);
9530 gcc_assert (TREE_CODE (arg) == OVERLOAD
9531 || TREE_CODE (arg) == FUNCTION_DECL);
9533 for (; arg; arg = OVL_NEXT (arg))
9534 good += try_one_overload (tparms, targs, tempargs, parm,
9535 TREE_TYPE (OVL_CURRENT (arg)),
9536 strict, sub_strict, addr_p);
9539 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9540 to function or pointer to member function argument if the set of
9541 overloaded functions does not contain function templates and at most
9542 one of a set of overloaded functions provides a unique match.
9544 So if we found multiple possibilities, we return success but don't
9549 int i = TREE_VEC_LENGTH (targs);
9551 if (TREE_VEC_ELT (tempargs, i))
9552 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9560 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9561 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9562 different overloads deduce different arguments for a given parm.
9563 ADDR_P is true if the expression for which deduction is being
9564 performed was of the form "& fn" rather than simply "fn".
9566 Returns 1 on success. */
9569 try_one_overload (tree tparms,
9574 unification_kind_t strict,
9582 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9583 to function or pointer to member function argument if the set of
9584 overloaded functions does not contain function templates and at most
9585 one of a set of overloaded functions provides a unique match.
9587 So if this is a template, just return success. */
9589 if (uses_template_parms (arg))
9592 if (TREE_CODE (arg) == METHOD_TYPE)
9593 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9595 arg = build_pointer_type (arg);
9597 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9599 /* We don't copy orig_targs for this because if we have already deduced
9600 some template args from previous args, unify would complain when we
9601 try to deduce a template parameter for the same argument, even though
9602 there isn't really a conflict. */
9603 nargs = TREE_VEC_LENGTH (targs);
9604 tempargs = make_tree_vec (nargs);
9606 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9609 /* First make sure we didn't deduce anything that conflicts with
9610 explicitly specified args. */
9611 for (i = nargs; i--; )
9613 tree elt = TREE_VEC_ELT (tempargs, i);
9614 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9616 if (elt == NULL_TREE)
9618 else if (uses_template_parms (elt))
9620 /* Since we're unifying against ourselves, we will fill in template
9621 args used in the function parm list with our own template parms.
9623 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9626 else if (oldelt && ! template_args_equal (oldelt, elt))
9630 for (i = nargs; i--; )
9632 tree elt = TREE_VEC_ELT (tempargs, i);
9635 TREE_VEC_ELT (targs, i) = elt;
9641 /* Verify that nondeduce template argument agrees with the type
9642 obtained from argument deduction. Return nonzero if the
9647 struct A { typedef int X; };
9648 template <class T, class U> struct C {};
9649 template <class T> struct C<T, typename T::X> {};
9651 Then with the instantiation `C<A, int>', we can deduce that
9652 `T' is `A' but unify () does not check whether `typename T::X'
9653 is `int'. This function ensure that they agree.
9655 TARGS, PARMS are the same as the arguments of unify.
9656 ARGS contains template arguments from all levels. */
9659 verify_class_unification (tree targs, tree parms, tree args)
9661 parms = tsubst (parms, add_outermost_template_args (args, targs),
9662 tf_none, NULL_TREE);
9663 if (parms == error_mark_node)
9666 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9669 /* PARM is a template class (perhaps with unbound template
9670 parameters). ARG is a fully instantiated type. If ARG can be
9671 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9672 TARGS are as for unify. */
9675 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9679 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9680 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9681 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9684 /* We need to make a new template argument vector for the call to
9685 unify. If we used TARGS, we'd clutter it up with the result of
9686 the attempted unification, even if this class didn't work out.
9687 We also don't want to commit ourselves to all the unifications
9688 we've already done, since unification is supposed to be done on
9689 an argument-by-argument basis. In other words, consider the
9690 following pathological case:
9692 template <int I, int J, int K>
9695 template <int I, int J>
9696 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9698 template <int I, int J, int K>
9699 void f(S<I, J, K>, S<I, I, I>);
9708 Now, by the time we consider the unification involving `s2', we
9709 already know that we must have `f<0, 0, 0>'. But, even though
9710 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9711 because there are two ways to unify base classes of S<0, 1, 2>
9712 with S<I, I, I>. If we kept the already deduced knowledge, we
9713 would reject the possibility I=1. */
9714 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9716 /* If unification failed, we're done. */
9717 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9718 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9724 /* Given a template type PARM and a class type ARG, find the unique
9725 base type in ARG that is an instance of PARM. We do not examine
9726 ARG itself; only its base-classes. If there is not exactly one
9727 appropriate base class, return NULL_TREE. PARM may be the type of
9728 a partial specialization, as well as a plain template type. Used
9732 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9734 tree rval = NULL_TREE;
9737 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9739 binfo = TYPE_BINFO (complete_type (arg));
9741 /* The type could not be completed. */
9744 /* Walk in inheritance graph order. The search order is not
9745 important, and this avoids multiple walks of virtual bases. */
9746 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9748 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9752 /* If there is more than one satisfactory baseclass, then:
9756 If they yield more than one possible deduced A, the type
9760 if (rval && !same_type_p (r, rval))
9770 /* Returns the level of DECL, which declares a template parameter. */
9773 template_decl_level (tree decl)
9775 switch (TREE_CODE (decl))
9779 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9782 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9790 /* Decide whether ARG can be unified with PARM, considering only the
9791 cv-qualifiers of each type, given STRICT as documented for unify.
9792 Returns nonzero iff the unification is OK on that basis. */
9795 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9797 int arg_quals = cp_type_quals (arg);
9798 int parm_quals = cp_type_quals (parm);
9800 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9801 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9803 /* Although a CVR qualifier is ignored when being applied to a
9804 substituted template parameter ([8.3.2]/1 for example), that
9805 does not apply during deduction [14.8.2.4]/1, (even though
9806 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9807 this). Except when we're allowing additional CV qualifiers
9808 at the outer level [14.8.2.1]/3,1st bullet. */
9809 if ((TREE_CODE (arg) == REFERENCE_TYPE
9810 || TREE_CODE (arg) == FUNCTION_TYPE
9811 || TREE_CODE (arg) == METHOD_TYPE)
9812 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9815 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9816 && (parm_quals & TYPE_QUAL_RESTRICT))
9820 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9821 && (arg_quals & parm_quals) != parm_quals)
9824 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9825 && (parm_quals & arg_quals) != arg_quals)
9831 /* Takes parameters as for type_unification. Returns 0 if the
9832 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9833 bitwise or of the following flags:
9836 Require an exact match between PARM and ARG.
9837 UNIFY_ALLOW_MORE_CV_QUAL:
9838 Allow the deduced ARG to be more cv-qualified (by qualification
9839 conversion) than ARG.
9840 UNIFY_ALLOW_LESS_CV_QUAL:
9841 Allow the deduced ARG to be less cv-qualified than ARG.
9842 UNIFY_ALLOW_DERIVED:
9843 Allow the deduced ARG to be a template base class of ARG,
9844 or a pointer to a template base class of the type pointed to by
9846 UNIFY_ALLOW_INTEGER:
9847 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9848 case for more information.
9849 UNIFY_ALLOW_OUTER_LEVEL:
9850 This is the outermost level of a deduction. Used to determine validity
9851 of qualification conversions. A valid qualification conversion must
9852 have const qualified pointers leading up to the inner type which
9853 requires additional CV quals, except at the outer level, where const
9854 is not required [conv.qual]. It would be normal to set this flag in
9855 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9856 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9857 This is the outermost level of a deduction, and PARM can be more CV
9858 qualified at this point.
9859 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9860 This is the outermost level of a deduction, and PARM can be less CV
9861 qualified at this point. */
9864 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9869 int strict_in = strict;
9871 /* I don't think this will do the right thing with respect to types.
9872 But the only case I've seen it in so far has been array bounds, where
9873 signedness is the only information lost, and I think that will be
9875 while (TREE_CODE (parm) == NOP_EXPR)
9876 parm = TREE_OPERAND (parm, 0);
9878 if (arg == error_mark_node)
9880 if (arg == unknown_type_node)
9881 /* We can't deduce anything from this, but we might get all the
9882 template args from other function args. */
9885 /* If PARM uses template parameters, then we can't bail out here,
9886 even if ARG == PARM, since we won't record unifications for the
9887 template parameters. We might need them if we're trying to
9888 figure out which of two things is more specialized. */
9889 if (arg == parm && !uses_template_parms (parm))
9892 /* Immediately reject some pairs that won't unify because of
9893 cv-qualification mismatches. */
9894 if (TREE_CODE (arg) == TREE_CODE (parm)
9896 /* It is the elements of the array which hold the cv quals of an array
9897 type, and the elements might be template type parms. We'll check
9899 && TREE_CODE (arg) != ARRAY_TYPE
9900 /* We check the cv-qualifiers when unifying with template type
9901 parameters below. We want to allow ARG `const T' to unify with
9902 PARM `T' for example, when computing which of two templates
9903 is more specialized, for example. */
9904 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9905 && !check_cv_quals_for_unify (strict_in, arg, parm))
9908 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9909 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9910 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9911 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9912 strict &= ~UNIFY_ALLOW_DERIVED;
9913 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9914 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9916 switch (TREE_CODE (parm))
9920 case UNBOUND_CLASS_TEMPLATE:
9921 /* In a type which contains a nested-name-specifier, template
9922 argument values cannot be deduced for template parameters used
9923 within the nested-name-specifier. */
9926 case TEMPLATE_TYPE_PARM:
9927 case TEMPLATE_TEMPLATE_PARM:
9928 case BOUND_TEMPLATE_TEMPLATE_PARM:
9929 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9931 if (TEMPLATE_TYPE_LEVEL (parm)
9932 != template_decl_level (tparm))
9933 /* The PARM is not one we're trying to unify. Just check
9934 to see if it matches ARG. */
9935 return (TREE_CODE (arg) == TREE_CODE (parm)
9936 && same_type_p (parm, arg)) ? 0 : 1;
9937 idx = TEMPLATE_TYPE_IDX (parm);
9938 targ = TREE_VEC_ELT (targs, idx);
9939 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9941 /* Check for mixed types and values. */
9942 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9943 && TREE_CODE (tparm) != TYPE_DECL)
9944 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9945 && TREE_CODE (tparm) != TEMPLATE_DECL))
9948 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9950 /* ARG must be constructed from a template class or a template
9951 template parameter. */
9952 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9953 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9957 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9958 tree parmvec = TYPE_TI_ARGS (parm);
9959 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9961 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9964 /* The parameter and argument roles have to be switched here
9965 in order to handle default arguments properly. For example,
9966 template<template <class> class TT> void f(TT<int>)
9967 should be able to accept vector<int> which comes from
9968 template <class T, class Allocator = allocator>
9971 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9975 /* Deduce arguments T, i from TT<T> or TT<i>.
9976 We check each element of PARMVEC and ARGVEC individually
9977 rather than the whole TREE_VEC since they can have
9978 different number of elements. */
9980 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9982 if (unify (tparms, targs,
9983 TREE_VEC_ELT (parmvec, i),
9984 TREE_VEC_ELT (argvec, i),
9989 arg = TYPE_TI_TEMPLATE (arg);
9991 /* Fall through to deduce template name. */
9994 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9995 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9997 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9999 /* Simple cases: Value already set, does match or doesn't. */
10000 if (targ != NULL_TREE && template_args_equal (targ, arg))
10007 /* If PARM is `const T' and ARG is only `int', we don't have
10008 a match unless we are allowing additional qualification.
10009 If ARG is `const int' and PARM is just `T' that's OK;
10010 that binds `const int' to `T'. */
10011 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10015 /* Consider the case where ARG is `const volatile int' and
10016 PARM is `const T'. Then, T should be `volatile int'. */
10017 arg = cp_build_qualified_type_real
10018 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10019 if (arg == error_mark_node)
10022 /* Simple cases: Value already set, does match or doesn't. */
10023 if (targ != NULL_TREE && same_type_p (targ, arg))
10028 /* Make sure that ARG is not a variable-sized array. (Note
10029 that were talking about variable-sized arrays (like
10030 `int[n]'), rather than arrays of unknown size (like
10031 `int[]').) We'll get very confused by such a type since
10032 the bound of the array will not be computable in an
10033 instantiation. Besides, such types are not allowed in
10034 ISO C++, so we can do as we please here. */
10035 if (variably_modified_type_p (arg, NULL_TREE))
10039 TREE_VEC_ELT (targs, idx) = arg;
10042 case TEMPLATE_PARM_INDEX:
10043 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10045 if (TEMPLATE_PARM_LEVEL (parm)
10046 != template_decl_level (tparm))
10047 /* The PARM is not one we're trying to unify. Just check
10048 to see if it matches ARG. */
10049 return !(TREE_CODE (arg) == TREE_CODE (parm)
10050 && cp_tree_equal (parm, arg));
10052 idx = TEMPLATE_PARM_IDX (parm);
10053 targ = TREE_VEC_ELT (targs, idx);
10056 return !cp_tree_equal (targ, arg);
10058 /* [temp.deduct.type] If, in the declaration of a function template
10059 with a non-type template-parameter, the non-type
10060 template-parameter is used in an expression in the function
10061 parameter-list and, if the corresponding template-argument is
10062 deduced, the template-argument type shall match the type of the
10063 template-parameter exactly, except that a template-argument
10064 deduced from an array bound may be of any integral type.
10065 The non-type parameter might use already deduced type parameters. */
10066 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10067 if (!TREE_TYPE (arg))
10068 /* Template-parameter dependent expression. Just accept it for now.
10069 It will later be processed in convert_template_argument. */
10071 else if (same_type_p (TREE_TYPE (arg), tparm))
10073 else if ((strict & UNIFY_ALLOW_INTEGER)
10074 && (TREE_CODE (tparm) == INTEGER_TYPE
10075 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10076 /* Convert the ARG to the type of PARM; the deduced non-type
10077 template argument must exactly match the types of the
10078 corresponding parameter. */
10079 arg = fold (build_nop (TREE_TYPE (parm), arg));
10080 else if (uses_template_parms (tparm))
10081 /* We haven't deduced the type of this parameter yet. Try again
10087 TREE_VEC_ELT (targs, idx) = arg;
10092 /* A pointer-to-member constant can be unified only with
10093 another constant. */
10094 if (TREE_CODE (arg) != PTRMEM_CST)
10097 /* Just unify the class member. It would be useless (and possibly
10098 wrong, depending on the strict flags) to unify also
10099 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10100 arg refer to the same variable, even if through different
10101 classes. For instance:
10103 struct A { int x; };
10106 Unification of &A::x and &B::x must succeed. */
10107 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10108 PTRMEM_CST_MEMBER (arg), strict);
10113 if (TREE_CODE (arg) != POINTER_TYPE)
10116 /* [temp.deduct.call]
10118 A can be another pointer or pointer to member type that can
10119 be converted to the deduced A via a qualification
10120 conversion (_conv.qual_).
10122 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10123 This will allow for additional cv-qualification of the
10124 pointed-to types if appropriate. */
10126 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10127 /* The derived-to-base conversion only persists through one
10128 level of pointers. */
10129 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10131 return unify (tparms, targs, TREE_TYPE (parm),
10132 TREE_TYPE (arg), strict);
10135 case REFERENCE_TYPE:
10136 if (TREE_CODE (arg) != REFERENCE_TYPE)
10138 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10139 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10142 if (TREE_CODE (arg) != ARRAY_TYPE)
10144 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10145 != (TYPE_DOMAIN (arg) == NULL_TREE))
10147 if (TYPE_DOMAIN (parm) != NULL_TREE)
10152 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10153 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10155 /* Our representation of array types uses "N - 1" as the
10156 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10157 not an integer constant. */
10158 if (TREE_CODE (parm_max) == MINUS_EXPR)
10160 arg_max = fold (build2 (PLUS_EXPR,
10163 TREE_OPERAND (parm_max, 1)));
10164 parm_max = TREE_OPERAND (parm_max, 0);
10167 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10170 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10171 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10178 case ENUMERAL_TYPE:
10180 if (TREE_CODE (arg) != TREE_CODE (parm))
10183 /* We have already checked cv-qualification at the top of the
10185 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10188 /* As far as unification is concerned, this wins. Later checks
10189 will invalidate it if necessary. */
10192 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10193 /* Type INTEGER_CST can come from ordinary constant template args. */
10195 while (TREE_CODE (arg) == NOP_EXPR)
10196 arg = TREE_OPERAND (arg, 0);
10198 if (TREE_CODE (arg) != INTEGER_CST)
10200 return !tree_int_cst_equal (parm, arg);
10205 if (TREE_CODE (arg) != TREE_VEC)
10207 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10209 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10210 if (unify (tparms, targs,
10211 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10219 if (TREE_CODE (arg) != TREE_CODE (parm))
10222 if (TYPE_PTRMEMFUNC_P (parm))
10224 if (!TYPE_PTRMEMFUNC_P (arg))
10227 return unify (tparms, targs,
10228 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10229 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10233 if (CLASSTYPE_TEMPLATE_INFO (parm))
10235 tree t = NULL_TREE;
10237 if (strict_in & UNIFY_ALLOW_DERIVED)
10239 /* First, we try to unify the PARM and ARG directly. */
10240 t = try_class_unification (tparms, targs,
10245 /* Fallback to the special case allowed in
10246 [temp.deduct.call]:
10248 If P is a class, and P has the form
10249 template-id, then A can be a derived class of
10250 the deduced A. Likewise, if P is a pointer to
10251 a class of the form template-id, A can be a
10252 pointer to a derived class pointed to by the
10254 t = get_template_base (tparms, targs, parm, arg);
10260 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10261 && (CLASSTYPE_TI_TEMPLATE (parm)
10262 == CLASSTYPE_TI_TEMPLATE (arg)))
10263 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10264 Then, we should unify `int' and `U'. */
10267 /* There's no chance of unification succeeding. */
10270 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10271 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10273 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10278 case FUNCTION_TYPE:
10279 if (TREE_CODE (arg) != TREE_CODE (parm))
10282 if (unify (tparms, targs, TREE_TYPE (parm),
10283 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10285 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10286 TYPE_ARG_TYPES (arg), 1,
10287 DEDUCE_EXACT, 0, -1);
10290 if (TREE_CODE (arg) != OFFSET_TYPE)
10292 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10293 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10295 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10299 if (DECL_TEMPLATE_PARM_P (parm))
10300 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10301 if (arg != integral_constant_value (parm))
10306 case TEMPLATE_DECL:
10307 /* Matched cases are handled by the ARG == PARM test above. */
10311 gcc_assert (EXPR_P (parm));
10313 /* We must be looking at an expression. This can happen with
10317 void foo(S<I>, S<I + 2>);
10319 This is a "nondeduced context":
10323 The nondeduced contexts are:
10325 --A type that is a template-id in which one or more of
10326 the template-arguments is an expression that references
10327 a template-parameter.
10329 In these cases, we assume deduction succeeded, but don't
10330 actually infer any unifications. */
10332 if (!uses_template_parms (parm)
10333 && !template_args_equal (parm, arg))
10340 /* Note that DECL can be defined in this translation unit, if
10344 mark_definable (tree decl)
10347 DECL_NOT_REALLY_EXTERN (decl) = 1;
10348 FOR_EACH_CLONE (clone, decl)
10349 DECL_NOT_REALLY_EXTERN (clone) = 1;
10352 /* Called if RESULT is explicitly instantiated, or is a member of an
10353 explicitly instantiated class. */
10356 mark_decl_instantiated (tree result, int extern_p)
10358 SET_DECL_EXPLICIT_INSTANTIATION (result);
10360 /* If this entity has already been written out, it's too late to
10361 make any modifications. */
10362 if (TREE_ASM_WRITTEN (result))
10365 if (TREE_CODE (result) != FUNCTION_DECL)
10366 /* The TREE_PUBLIC flag for function declarations will have been
10367 set correctly by tsubst. */
10368 TREE_PUBLIC (result) = 1;
10370 /* This might have been set by an earlier implicit instantiation. */
10371 DECL_COMDAT (result) = 0;
10374 DECL_NOT_REALLY_EXTERN (result) = 0;
10377 mark_definable (result);
10378 /* Always make artificials weak. */
10379 if (DECL_ARTIFICIAL (result) && flag_weak)
10380 comdat_linkage (result);
10381 /* For WIN32 we also want to put explicit instantiations in
10382 linkonce sections. */
10383 else if (TREE_PUBLIC (result))
10384 maybe_make_one_only (result);
10387 /* If EXTERN_P, then this function will not be emitted -- unless
10388 followed by an explicit instantiation, at which point its linkage
10389 will be adjusted. If !EXTERN_P, then this function will be
10390 emitted here. In neither circumstance do we want
10391 import_export_decl to adjust the linkage. */
10392 DECL_INTERFACE_KNOWN (result) = 1;
10395 /* Given two function templates PAT1 and PAT2, return:
10397 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
10399 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10400 -1 if PAT2 is more specialized than PAT1.
10401 0 if neither is more specialized.
10403 LEN is passed through to fn_type_unification. */
10406 more_specialized (tree pat1, tree pat2, int deduce, int len)
10411 /* If template argument deduction succeeds, we substitute the
10412 resulting arguments into non-deduced contexts. While doing that,
10413 we must be aware that we may encounter dependent types. */
10414 ++processing_template_decl;
10415 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
10416 NULL_TREE, 0, deduce, len);
10420 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
10421 NULL_TREE, 0, deduce, len);
10424 --processing_template_decl;
10429 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10431 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10432 -1 if PAT2 is more specialized than PAT1.
10433 0 if neither is more specialized.
10435 FULL_ARGS is the full set of template arguments that triggers this
10436 partial ordering. */
10439 more_specialized_class (tree pat1, tree pat2, tree full_args)
10444 /* Just like what happens for functions, if we are ordering between
10445 different class template specializations, we may encounter dependent
10446 types in the arguments, and we need our dependency check functions
10447 to behave correctly. */
10448 ++processing_template_decl;
10449 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10450 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10454 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10455 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10458 --processing_template_decl;
10463 /* Return the template arguments that will produce the function signature
10464 DECL from the function template FN, with the explicit template
10465 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
10466 also match. Return NULL_TREE if no satisfactory arguments could be
10467 found. DEDUCE and LEN are passed through to fn_type_unification. */
10470 get_bindings_real (tree fn,
10472 tree explicit_args,
10477 int ntparms = DECL_NTPARMS (fn);
10478 tree targs = make_tree_vec (ntparms);
10480 tree decl_arg_types;
10483 /* Substitute the explicit template arguments into the type of DECL.
10484 The call to fn_type_unification will handle substitution into the
10486 decl_type = TREE_TYPE (decl);
10487 if (explicit_args && uses_template_parms (decl_type))
10490 tree converted_args;
10492 if (DECL_TEMPLATE_INFO (decl))
10493 tmpl = DECL_TI_TEMPLATE (decl);
10495 /* We can get here for some invalid specializations. */
10499 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10500 explicit_args, NULL_TREE,
10501 tf_none, /*require_all_arguments=*/0));
10502 if (converted_args == error_mark_node)
10505 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10506 if (decl_type == error_mark_node)
10510 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10511 /* Never do unification on the 'this' parameter. */
10512 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10513 decl_arg_types = TREE_CHAIN (decl_arg_types);
10515 i = fn_type_unification (fn, explicit_args, targs,
10517 (check_rettype || DECL_CONV_FN_P (fn)
10518 ? TREE_TYPE (decl_type) : NULL_TREE),
10527 /* For most uses, we want to check the return type. */
10530 get_bindings (tree fn, tree decl, tree explicit_args)
10532 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10535 /* But for resolve_overloaded_unification, we only care about the parameter
10539 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10541 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10544 /* Return the innermost template arguments that, when applied to a
10545 template specialization whose innermost template parameters are
10546 TPARMS, and whose specialization arguments are PARMS, yield the
10549 For example, suppose we have:
10551 template <class T, class U> struct S {};
10552 template <class T> struct S<T*, int> {};
10554 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10555 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10556 int}. The resulting vector will be {double}, indicating that `T'
10557 is bound to `double'. */
10560 get_class_bindings (tree tparms, tree parms, tree args)
10562 int i, ntparms = TREE_VEC_LENGTH (tparms);
10563 tree vec = make_tree_vec (ntparms);
10565 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10569 for (i = 0; i < ntparms; ++i)
10570 if (! TREE_VEC_ELT (vec, i))
10573 if (verify_class_unification (vec, parms, args))
10579 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10580 Pick the most specialized template, and return the corresponding
10581 instantiation, or if there is no corresponding instantiation, the
10582 template itself. If there is no most specialized template,
10583 error_mark_node is returned. If there are no templates at all,
10584 NULL_TREE is returned. */
10587 most_specialized_instantiation (tree instantiations)
10592 if (!instantiations)
10595 champ = instantiations;
10596 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10598 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10606 fn = TREE_CHAIN (fn);
10608 return error_mark_node;
10614 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10616 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10619 return error_mark_node;
10622 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10625 /* Return the most specialized of the list of templates in FNS that can
10626 produce an instantiation matching DECL, given the explicit template
10627 arguments EXPLICIT_ARGS. */
10630 most_specialized (tree fns, tree decl, tree explicit_args)
10632 tree candidates = NULL_TREE;
10635 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10637 tree candidate = TREE_VALUE (fn);
10639 args = get_bindings (candidate, decl, explicit_args);
10641 candidates = tree_cons (NULL_TREE, candidate, candidates);
10644 return most_specialized_instantiation (candidates);
10647 /* If DECL is a specialization of some template, return the most
10648 general such template. Otherwise, returns NULL_TREE.
10650 For example, given:
10652 template <class T> struct S { template <class U> void f(U); };
10654 if TMPL is `template <class U> void S<int>::f(U)' this will return
10655 the full template. This function will not trace past partial
10656 specializations, however. For example, given in addition:
10658 template <class T> struct S<T*> { template <class U> void f(U); };
10660 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10661 `template <class T> template <class U> S<T*>::f(U)'. */
10664 most_general_template (tree decl)
10666 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10667 an immediate specialization. */
10668 if (TREE_CODE (decl) == FUNCTION_DECL)
10670 if (DECL_TEMPLATE_INFO (decl)) {
10671 decl = DECL_TI_TEMPLATE (decl);
10673 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10674 template friend. */
10675 if (TREE_CODE (decl) != TEMPLATE_DECL)
10681 /* Look for more and more general templates. */
10682 while (DECL_TEMPLATE_INFO (decl))
10684 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10685 (See cp-tree.h for details.) */
10686 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10689 if (CLASS_TYPE_P (TREE_TYPE (decl))
10690 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10693 /* Stop if we run into an explicitly specialized class template. */
10694 if (!DECL_NAMESPACE_SCOPE_P (decl)
10695 && DECL_CONTEXT (decl)
10696 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10699 decl = DECL_TI_TEMPLATE (decl);
10705 /* Return the most specialized of the class template specializations
10706 of TMPL which can produce an instantiation matching ARGS, or
10707 error_mark_node if the choice is ambiguous. */
10710 most_specialized_class (tree tmpl, tree args)
10712 tree list = NULL_TREE;
10717 tmpl = most_general_template (tmpl);
10718 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10721 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10724 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10725 TREE_TYPE (list) = TREE_TYPE (t);
10734 t = TREE_CHAIN (t);
10735 for (; t; t = TREE_CHAIN (t))
10737 fate = more_specialized_class (champ, t, args);
10744 t = TREE_CHAIN (t);
10746 return error_mark_node;
10752 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10754 fate = more_specialized_class (champ, t, args);
10756 return error_mark_node;
10762 /* Explicitly instantiate DECL. */
10765 do_decl_instantiation (tree decl, tree storage)
10767 tree result = NULL_TREE;
10771 /* An error occurred, for which grokdeclarator has already issued
10772 an appropriate message. */
10774 else if (! DECL_LANG_SPECIFIC (decl))
10776 error ("explicit instantiation of non-template %q#D", decl);
10779 else if (TREE_CODE (decl) == VAR_DECL)
10781 /* There is an asymmetry here in the way VAR_DECLs and
10782 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10783 the latter, the DECL we get back will be marked as a
10784 template instantiation, and the appropriate
10785 DECL_TEMPLATE_INFO will be set up. This does not happen for
10786 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10787 should handle VAR_DECLs as it currently handles
10789 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10790 if (!result || TREE_CODE (result) != VAR_DECL)
10792 error ("no matching template for %qD found", decl);
10796 else if (TREE_CODE (decl) != FUNCTION_DECL)
10798 error ("explicit instantiation of %q#D", decl);
10804 /* Check for various error cases. Note that if the explicit
10805 instantiation is valid the RESULT will currently be marked as an
10806 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10807 until we get here. */
10809 if (DECL_TEMPLATE_SPECIALIZATION (result))
10811 /* DR 259 [temp.spec].
10813 Both an explicit instantiation and a declaration of an explicit
10814 specialization shall not appear in a program unless the explicit
10815 instantiation follows a declaration of the explicit specialization.
10817 For a given set of template parameters, if an explicit
10818 instantiation of a template appears after a declaration of an
10819 explicit specialization for that template, the explicit
10820 instantiation has no effect. */
10823 else if (DECL_EXPLICIT_INSTANTIATION (result))
10827 No program shall explicitly instantiate any template more
10830 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10831 the first instantiation was `extern' and the second is not,
10832 and EXTERN_P for the opposite case. */
10833 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10834 pedwarn ("duplicate explicit instantiation of %q#D", result);
10835 /* If an "extern" explicit instantiation follows an ordinary
10836 explicit instantiation, the template is instantiated. */
10840 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10842 error ("no matching template for %qD found", result);
10845 else if (!DECL_TEMPLATE_INFO (result))
10847 pedwarn ("explicit instantiation of non-template %q#D", result);
10851 if (storage == NULL_TREE)
10853 else if (storage == ridpointers[(int) RID_EXTERN])
10855 if (pedantic && !in_system_header)
10856 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
10861 error ("storage class %qD applied to template instantiation", storage);
10863 mark_decl_instantiated (result, extern_p);
10865 instantiate_decl (result, /*defer_ok=*/1, /*undefined_ok=*/0);
10869 mark_class_instantiated (tree t, int extern_p)
10871 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10872 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10873 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10874 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10877 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10878 rest_of_type_compilation (t, 1);
10882 /* Called from do_type_instantiation through binding_table_foreach to
10883 do recursive instantiation for the type bound in ENTRY. */
10885 bt_instantiate_type_proc (binding_entry entry, void *data)
10887 tree storage = *(tree *) data;
10889 if (IS_AGGR_TYPE (entry->type)
10890 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10891 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10894 /* Called from do_type_instantiation to instantiate a member
10895 (a member function or a static member variable) of an
10896 explicitly instantiated class template. */
10898 instantiate_class_member (tree decl, int extern_p)
10900 mark_decl_instantiated (decl, extern_p);
10902 instantiate_decl (decl, /*defer_ok=*/1, /* undefined_ok=*/1);
10905 /* Perform an explicit instantiation of template class T. STORAGE, if
10906 non-null, is the RID for extern, inline or static. COMPLAIN is
10907 nonzero if this is called from the parser, zero if called recursively,
10908 since the standard is unclear (as detailed below). */
10911 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10916 int previous_instantiation_extern_p = 0;
10918 if (TREE_CODE (t) == TYPE_DECL)
10921 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10923 error ("explicit instantiation of non-template type %qT", t);
10929 if (!COMPLETE_TYPE_P (t))
10931 if (complain & tf_error)
10932 error ("explicit instantiation of %q#T before definition of template",
10937 if (storage != NULL_TREE)
10939 if (pedantic && !in_system_header)
10940 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
10943 if (storage == ridpointers[(int) RID_INLINE])
10945 else if (storage == ridpointers[(int) RID_EXTERN])
10947 else if (storage == ridpointers[(int) RID_STATIC])
10951 error ("storage class %qD applied to template instantiation",
10957 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10959 /* DR 259 [temp.spec].
10961 Both an explicit instantiation and a declaration of an explicit
10962 specialization shall not appear in a program unless the explicit
10963 instantiation follows a declaration of the explicit specialization.
10965 For a given set of template parameters, if an explicit
10966 instantiation of a template appears after a declaration of an
10967 explicit specialization for that template, the explicit
10968 instantiation has no effect. */
10971 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10975 No program shall explicitly instantiate any template more
10978 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
10979 instantiation was `extern'. If EXTERN_P then the second is.
10980 These cases are OK. */
10981 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
10983 if (!previous_instantiation_extern_p && !extern_p
10984 && (complain & tf_error))
10985 pedwarn ("duplicate explicit instantiation of %q#T", t);
10987 /* If we've already instantiated the template, just return now. */
10988 if (!CLASSTYPE_INTERFACE_ONLY (t))
10992 mark_class_instantiated (t, extern_p);
11000 /* In contrast to implicit instantiation, where only the
11001 declarations, and not the definitions, of members are
11002 instantiated, we have here:
11006 The explicit instantiation of a class template specialization
11007 implies the instantiation of all of its members not
11008 previously explicitly specialized in the translation unit
11009 containing the explicit instantiation.
11011 Of course, we can't instantiate member template classes, since
11012 we don't have any arguments for them. Note that the standard
11013 is unclear on whether the instantiation of the members are
11014 *explicit* instantiations or not. However, the most natural
11015 interpretation is that it should be an explicit instantiation. */
11018 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11019 if (TREE_CODE (tmp) == FUNCTION_DECL
11020 && DECL_TEMPLATE_INSTANTIATION (tmp))
11021 instantiate_class_member (tmp, extern_p);
11023 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11024 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11025 instantiate_class_member (tmp, extern_p);
11027 if (CLASSTYPE_NESTED_UTDS (t))
11028 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11029 bt_instantiate_type_proc, &storage);
11033 /* Given a function DECL, which is a specialization of TMPL, modify
11034 DECL to be a re-instantiation of TMPL with the same template
11035 arguments. TMPL should be the template into which tsubst'ing
11036 should occur for DECL, not the most general template.
11038 One reason for doing this is a scenario like this:
11041 void f(const T&, int i);
11043 void g() { f(3, 7); }
11046 void f(const T& t, const int i) { }
11048 Note that when the template is first instantiated, with
11049 instantiate_template, the resulting DECL will have no name for the
11050 first parameter, and the wrong type for the second. So, when we go
11051 to instantiate the DECL, we regenerate it. */
11054 regenerate_decl_from_template (tree decl, tree tmpl)
11056 /* The arguments used to instantiate DECL, from the most general
11061 args = DECL_TI_ARGS (decl);
11062 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11064 /* Make sure that we can see identifiers, and compute access
11066 push_access_scope (decl);
11068 if (TREE_CODE (decl) == FUNCTION_DECL)
11076 args_depth = TMPL_ARGS_DEPTH (args);
11077 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11078 if (args_depth > parms_depth)
11079 args = get_innermost_template_args (args, parms_depth);
11081 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11082 args, tf_error, NULL_TREE);
11084 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11087 /* Merge parameter declarations. */
11088 decl_parm = skip_artificial_parms_for (decl,
11089 DECL_ARGUMENTS (decl));
11091 = skip_artificial_parms_for (code_pattern,
11092 DECL_ARGUMENTS (code_pattern));
11097 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11098 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11099 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11101 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11102 TREE_TYPE (decl_parm) = parm_type;
11103 decl_parm = TREE_CHAIN (decl_parm);
11104 pattern_parm = TREE_CHAIN (pattern_parm);
11107 /* Merge additional specifiers from the CODE_PATTERN. */
11108 if (DECL_DECLARED_INLINE_P (code_pattern)
11109 && !DECL_DECLARED_INLINE_P (decl))
11110 DECL_DECLARED_INLINE_P (decl) = 1;
11111 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11112 DECL_INLINE (decl) = 1;
11114 else if (TREE_CODE (decl) == VAR_DECL)
11116 if (!DECL_INITIALIZED_IN_CLASS_P (decl)
11117 && DECL_INITIAL (code_pattern))
11118 DECL_INITIAL (decl) =
11119 tsubst_expr (DECL_INITIAL (code_pattern), args,
11120 tf_error, DECL_TI_TEMPLATE (decl));
11123 gcc_unreachable ();
11125 pop_access_scope (decl);
11128 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11129 substituted to get DECL. */
11132 template_for_substitution (tree decl)
11134 tree tmpl = DECL_TI_TEMPLATE (decl);
11136 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11137 for the instantiation. This is not always the most general
11138 template. Consider, for example:
11141 struct S { template <class U> void f();
11142 template <> void f<int>(); };
11144 and an instantiation of S<double>::f<int>. We want TD to be the
11145 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11146 while (/* An instantiation cannot have a definition, so we need a
11147 more general template. */
11148 DECL_TEMPLATE_INSTANTIATION (tmpl)
11149 /* We must also deal with friend templates. Given:
11151 template <class T> struct S {
11152 template <class U> friend void f() {};
11155 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11156 so far as the language is concerned, but that's still
11157 where we get the pattern for the instantiation from. On
11158 other hand, if the definition comes outside the class, say:
11160 template <class T> struct S {
11161 template <class U> friend void f();
11163 template <class U> friend void f() {}
11165 we don't need to look any further. That's what the check for
11166 DECL_INITIAL is for. */
11167 || (TREE_CODE (decl) == FUNCTION_DECL
11168 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11169 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11171 /* The present template, TD, should not be a definition. If it
11172 were a definition, we should be using it! Note that we
11173 cannot restructure the loop to just keep going until we find
11174 a template with a definition, since that might go too far if
11175 a specialization was declared, but not defined. */
11176 gcc_assert (TREE_CODE (decl) != VAR_DECL
11177 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11179 /* Fetch the more general template. */
11180 tmpl = DECL_TI_TEMPLATE (tmpl);
11186 /* Produce the definition of D, a _DECL generated from a template. If
11187 DEFER_OK is nonzero, then we don't have to actually do the
11188 instantiation now; we just have to do it sometime. Normally it is
11189 an error if this is an explicit instantiation but D is undefined.
11190 If UNDEFINED_OK is nonzero, then instead we treat it as an implicit
11191 instantiation. UNDEFINED_OK is nonzero only if we are being used
11192 to instantiate the members of an explicitly instantiated class
11197 instantiate_decl (tree d, int defer_ok, int undefined_ok)
11199 tree tmpl = DECL_TI_TEMPLATE (d);
11206 int pattern_defined;
11208 location_t saved_loc = input_location;
11210 /* This function should only be used to instantiate templates for
11211 functions and static member variables. */
11212 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11213 || TREE_CODE (d) == VAR_DECL);
11215 /* Variables are never deferred; if instantiation is required, they
11216 are instantiated right away. That allows for better code in the
11217 case that an expression refers to the value of the variable --
11218 if the variable has a constant value the referring expression can
11219 take advantage of that fact. */
11220 if (TREE_CODE (d) == VAR_DECL)
11223 /* Don't instantiate cloned functions. Instead, instantiate the
11224 functions they cloned. */
11225 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11226 d = DECL_CLONED_FUNCTION (d);
11228 if (DECL_TEMPLATE_INSTANTIATED (d))
11229 /* D has already been instantiated. It might seem reasonable to
11230 check whether or not D is an explicit instantiation, and, if so,
11231 stop here. But when an explicit instantiation is deferred
11232 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11233 is set, even though we still need to do the instantiation. */
11236 /* If we already have a specialization of this declaration, then
11237 there's no reason to instantiate it. Note that
11238 retrieve_specialization gives us both instantiations and
11239 specializations, so we must explicitly check
11240 DECL_TEMPLATE_SPECIALIZATION. */
11241 gen_tmpl = most_general_template (tmpl);
11242 gen_args = DECL_TI_ARGS (d);
11243 spec = retrieve_specialization (gen_tmpl, gen_args,
11244 /*class_specializations_p=*/false);
11245 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11248 /* This needs to happen before any tsubsting. */
11249 if (! push_tinst_level (d))
11252 timevar_push (TV_PARSE);
11254 /* We may be in the middle of deferred access check. Disable it now. */
11255 push_deferring_access_checks (dk_no_deferred);
11257 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11258 for the instantiation. */
11259 td = template_for_substitution (d);
11260 code_pattern = DECL_TEMPLATE_RESULT (td);
11262 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11263 || DECL_TEMPLATE_SPECIALIZATION (td))
11264 /* In the case of a friend template whose definition is provided
11265 outside the class, we may have too many arguments. Drop the
11266 ones we don't need. The same is true for specializations. */
11267 args = get_innermost_template_args
11268 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11272 if (TREE_CODE (d) == FUNCTION_DECL)
11273 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11275 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11276 /* Unless an explicit instantiation directive has already determined
11277 the linkage of D, remember that a definition is available for
11279 if (pattern_defined
11280 && !DECL_INTERFACE_KNOWN (d)
11281 && !DECL_NOT_REALLY_EXTERN (d))
11282 mark_definable (d);
11284 input_location = DECL_SOURCE_LOCATION (d);
11286 if (! pattern_defined && DECL_EXPLICIT_INSTANTIATION (d) && undefined_ok)
11288 DECL_NOT_REALLY_EXTERN (d) = 0;
11289 SET_DECL_IMPLICIT_INSTANTIATION (d);
11294 /* Recheck the substitutions to obtain any warning messages
11295 about ignoring cv qualifiers. */
11296 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11297 tree type = TREE_TYPE (gen);
11299 /* Make sure that we can see identifiers, and compute access
11300 correctly. D is already the target FUNCTION_DECL with the
11302 push_access_scope (d);
11304 if (TREE_CODE (gen) == FUNCTION_DECL)
11306 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11307 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11308 tf_error | tf_warning, d);
11309 /* Don't simply tsubst the function type, as that will give
11310 duplicate warnings about poor parameter qualifications.
11311 The function arguments are the same as the decl_arguments
11312 without the top level cv qualifiers. */
11313 type = TREE_TYPE (type);
11315 tsubst (type, gen_args, tf_error | tf_warning, d);
11317 pop_access_scope (d);
11320 /* We should have set up DECL_INITIAL in instantiate_class_template
11321 for in-class definitions of static data members. */
11322 gcc_assert (!(TREE_CODE (d) == VAR_DECL
11323 && DECL_INITIALIZED_IN_CLASS_P (d)
11324 && DECL_INITIAL (d) == NULL_TREE));
11326 /* Do not instantiate templates that we know will be defined
11328 if (DECL_INTERFACE_KNOWN (d)
11329 && DECL_REALLY_EXTERN (d)
11330 && ! (TREE_CODE (d) == FUNCTION_DECL
11331 && DECL_INLINE (d)))
11333 /* Defer all other templates, unless we have been explicitly
11334 forbidden from doing so. We restore the source position here
11335 because it's used by add_pending_template. */
11336 else if (! pattern_defined || defer_ok)
11338 input_location = saved_loc;
11340 if (at_eof && !pattern_defined
11341 && DECL_EXPLICIT_INSTANTIATION (d))
11344 The definition of a non-exported function template, a
11345 non-exported member function template, or a non-exported
11346 member function or static data member of a class template
11347 shall be present in every translation unit in which it is
11348 explicitly instantiated. */
11350 ("explicit instantiation of %qD but no definition available", d);
11352 add_pending_template (d);
11355 /* Tell the repository that D is available in this translation unit
11356 -- and see if it is supposed to be instantiated here. */
11357 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11359 /* In a PCH file, despite the fact that the repository hasn't
11360 requested instantiation in the PCH it is still possible that
11361 an instantiation will be required in a file that includes the
11364 add_pending_template (d);
11365 /* Instantiate inline functions so that the inliner can do its
11366 job, even though we'll not be emitting a copy of this
11368 if (!(TREE_CODE (d) == FUNCTION_DECL
11369 && flag_inline_trees
11370 && DECL_DECLARED_INLINE_P (d)))
11374 need_push = !cfun || !global_bindings_p ();
11376 push_to_top_level ();
11378 /* Mark D as instantiated so that recursive calls to
11379 instantiate_decl do not try to instantiate it again. */
11380 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11382 /* Regenerate the declaration in case the template has been modified
11383 by a subsequent redeclaration. */
11384 regenerate_decl_from_template (d, td);
11386 /* We already set the file and line above. Reset them now in case
11387 they changed as a result of calling regenerate_decl_from_template. */
11388 input_location = DECL_SOURCE_LOCATION (d);
11390 if (TREE_CODE (d) == VAR_DECL)
11392 /* Clear out DECL_RTL; whatever was there before may not be right
11393 since we've reset the type of the declaration. */
11394 SET_DECL_RTL (d, NULL_RTX);
11395 DECL_IN_AGGR_P (d) = 0;
11397 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11398 initializer. That function will defer actual emission until
11399 we have a chance to determine linkage. */
11400 DECL_EXTERNAL (d) = 0;
11402 /* Enter the scope of D so that access-checking works correctly. */
11403 push_nested_class (DECL_CONTEXT (d));
11405 (!DECL_INITIALIZED_IN_CLASS_P (d)
11406 ? DECL_INITIAL (d) : NULL_TREE),
11408 pop_nested_class ();
11410 else if (TREE_CODE (d) == FUNCTION_DECL)
11412 htab_t saved_local_specializations;
11417 /* Save away the current list, in case we are instantiating one
11418 template from within the body of another. */
11419 saved_local_specializations = local_specializations;
11421 /* Set up the list of local specializations. */
11422 local_specializations = htab_create (37,
11423 hash_local_specialization,
11424 eq_local_specializations,
11427 /* Set up context. */
11428 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11430 /* Create substitution entries for the parameters. */
11431 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11432 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11433 spec_parm = DECL_ARGUMENTS (d);
11434 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11436 register_local_specialization (spec_parm, tmpl_parm);
11437 spec_parm = skip_artificial_parms_for (d, spec_parm);
11438 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11442 register_local_specialization (spec_parm, tmpl_parm);
11443 tmpl_parm = TREE_CHAIN (tmpl_parm);
11444 spec_parm = TREE_CHAIN (spec_parm);
11446 gcc_assert (!spec_parm);
11448 /* Substitute into the body of the function. */
11449 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11450 tf_error | tf_warning, tmpl);
11452 /* We don't need the local specializations any more. */
11453 htab_delete (local_specializations);
11454 local_specializations = saved_local_specializations;
11456 /* Finish the function. */
11457 d = finish_function (0);
11458 expand_or_defer_fn (d);
11461 /* We're not deferring instantiation any more. */
11462 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11465 pop_from_top_level ();
11468 input_location = saved_loc;
11469 pop_deferring_access_checks ();
11470 pop_tinst_level ();
11472 timevar_pop (TV_PARSE);
11477 /* Run through the list of templates that we wish we could
11478 instantiate, and instantiate any we can. RETRIES is the
11479 number of times we retry pending template instantiation. */
11482 instantiate_pending_templates (int retries)
11485 tree last = NULL_TREE;
11487 location_t saved_loc = input_location;
11489 /* Instantiating templates may trigger vtable generation. This in turn
11490 may require further template instantiations. We place a limit here
11491 to avoid infinite loop. */
11492 if (pending_templates && retries >= max_tinst_depth)
11494 cp_error_at ("template instantiation depth exceeds maximum of %d"
11495 " (use -ftemplate-depth-NN to increase the maximum)"
11496 " instantiating %q+D, possibly from virtual table"
11498 max_tinst_depth, TREE_VALUE (pending_templates));
11506 t = &pending_templates;
11509 tree instantiation = TREE_VALUE (*t);
11511 reopen_tinst_level (TREE_PURPOSE (*t));
11513 if (TYPE_P (instantiation))
11517 if (!COMPLETE_TYPE_P (instantiation))
11519 instantiate_class_template (instantiation);
11520 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11521 for (fn = TYPE_METHODS (instantiation);
11523 fn = TREE_CHAIN (fn))
11524 if (! DECL_ARTIFICIAL (fn))
11525 instantiate_decl (fn, /*defer_ok=*/0,
11526 /*undefined_ok=*/0);
11527 if (COMPLETE_TYPE_P (instantiation))
11531 if (COMPLETE_TYPE_P (instantiation))
11532 /* If INSTANTIATION has been instantiated, then we don't
11533 need to consider it again in the future. */
11534 *t = TREE_CHAIN (*t);
11538 t = &TREE_CHAIN (*t);
11543 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11544 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11546 instantiation = instantiate_decl (instantiation,
11548 /*undefined_ok=*/0);
11549 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11553 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11554 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11555 /* If INSTANTIATION has been instantiated, then we don't
11556 need to consider it again in the future. */
11557 *t = TREE_CHAIN (*t);
11561 t = &TREE_CHAIN (*t);
11565 current_tinst_level = NULL_TREE;
11567 last_pending_template = last;
11569 while (reconsider);
11571 input_location = saved_loc;
11574 /* Substitute ARGVEC into T, which is a list of initializers for
11575 either base class or a non-static data member. The TREE_PURPOSEs
11576 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11577 instantiate_decl. */
11580 tsubst_initializer_list (tree t, tree argvec)
11582 tree inits = NULL_TREE;
11584 for (; t; t = TREE_CHAIN (t))
11589 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11591 decl = expand_member_init (decl);
11592 if (decl && !DECL_P (decl))
11593 in_base_initializer = 1;
11595 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11597 in_base_initializer = 0;
11601 init = build_tree_list (decl, init);
11602 TREE_CHAIN (init) = inits;
11609 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11612 set_current_access_from_decl (tree decl)
11614 if (TREE_PRIVATE (decl))
11615 current_access_specifier = access_private_node;
11616 else if (TREE_PROTECTED (decl))
11617 current_access_specifier = access_protected_node;
11619 current_access_specifier = access_public_node;
11622 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11623 is the instantiation (which should have been created with
11624 start_enum) and ARGS are the template arguments to use. */
11627 tsubst_enum (tree tag, tree newtag, tree args)
11631 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11636 decl = TREE_VALUE (e);
11637 /* Note that in a template enum, the TREE_VALUE is the
11638 CONST_DECL, not the corresponding INTEGER_CST. */
11639 value = tsubst_expr (DECL_INITIAL (decl),
11640 args, tf_error | tf_warning,
11643 /* Give this enumeration constant the correct access. */
11644 set_current_access_from_decl (decl);
11646 /* Actually build the enumerator itself. */
11647 build_enumerator (DECL_NAME (decl), value, newtag);
11650 finish_enum (newtag);
11651 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11652 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11655 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11656 its type -- but without substituting the innermost set of template
11657 arguments. So, innermost set of template parameters will appear in
11661 get_mostly_instantiated_function_type (tree decl)
11669 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11670 targs = DECL_TI_ARGS (decl);
11671 tparms = DECL_TEMPLATE_PARMS (tmpl);
11672 parm_depth = TMPL_PARMS_DEPTH (tparms);
11674 /* There should be as many levels of arguments as there are levels
11676 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11678 fn_type = TREE_TYPE (tmpl);
11680 if (parm_depth == 1)
11681 /* No substitution is necessary. */
11688 /* Replace the innermost level of the TARGS with NULL_TREEs to
11689 let tsubst know not to substitute for those parameters. */
11690 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11691 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11692 SET_TMPL_ARGS_LEVEL (partial_args, i,
11693 TMPL_ARGS_LEVEL (targs, i));
11694 SET_TMPL_ARGS_LEVEL (partial_args,
11695 TMPL_ARGS_DEPTH (targs),
11696 make_tree_vec (DECL_NTPARMS (tmpl)));
11698 /* Make sure that we can see identifiers, and compute access
11699 correctly. We can just use the context of DECL for the
11700 partial substitution here. It depends only on outer template
11701 parameters, regardless of whether the innermost level is
11702 specialized or not. */
11703 push_access_scope (decl);
11705 ++processing_template_decl;
11706 /* Now, do the (partial) substitution to figure out the
11707 appropriate function type. */
11708 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11709 --processing_template_decl;
11711 /* Substitute into the template parameters to obtain the real
11712 innermost set of parameters. This step is important if the
11713 innermost set of template parameters contains value
11714 parameters whose types depend on outer template parameters. */
11715 TREE_VEC_LENGTH (partial_args)--;
11716 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11718 pop_access_scope (decl);
11724 /* Return truthvalue if we're processing a template different from
11725 the last one involved in diagnostics. */
11727 problematic_instantiation_changed (void)
11729 return last_template_error_tick != tinst_level_tick;
11732 /* Remember current template involved in diagnostics. */
11734 record_last_problematic_instantiation (void)
11736 last_template_error_tick = tinst_level_tick;
11740 current_instantiation (void)
11742 return current_tinst_level;
11745 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11746 type. Return zero for ok, nonzero for disallowed. Issue error and
11747 warning messages under control of COMPLAIN. */
11750 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11752 if (INTEGRAL_TYPE_P (type))
11754 else if (POINTER_TYPE_P (type))
11756 else if (TYPE_PTR_TO_MEMBER_P (type))
11758 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11760 else if (TREE_CODE (type) == TYPENAME_TYPE)
11763 if (complain & tf_error)
11764 error ("%q#T is not a valid type for a template constant parameter", type);
11768 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11769 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11772 dependent_type_p_r (tree type)
11778 A type is dependent if it is:
11780 -- a template parameter. Template template parameters are types
11781 for us (since TYPE_P holds true for them) so we handle
11783 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11784 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11786 /* -- a qualified-id with a nested-name-specifier which contains a
11787 class-name that names a dependent type or whose unqualified-id
11788 names a dependent type. */
11789 if (TREE_CODE (type) == TYPENAME_TYPE)
11791 /* -- a cv-qualified type where the cv-unqualified type is
11793 type = TYPE_MAIN_VARIANT (type);
11794 /* -- a compound type constructed from any dependent type. */
11795 if (TYPE_PTR_TO_MEMBER_P (type))
11796 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11797 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11799 else if (TREE_CODE (type) == POINTER_TYPE
11800 || TREE_CODE (type) == REFERENCE_TYPE)
11801 return dependent_type_p (TREE_TYPE (type));
11802 else if (TREE_CODE (type) == FUNCTION_TYPE
11803 || TREE_CODE (type) == METHOD_TYPE)
11807 if (dependent_type_p (TREE_TYPE (type)))
11809 for (arg_type = TYPE_ARG_TYPES (type);
11811 arg_type = TREE_CHAIN (arg_type))
11812 if (dependent_type_p (TREE_VALUE (arg_type)))
11816 /* -- an array type constructed from any dependent type or whose
11817 size is specified by a constant expression that is
11818 value-dependent. */
11819 if (TREE_CODE (type) == ARRAY_TYPE)
11821 if (TYPE_DOMAIN (type)
11822 && ((value_dependent_expression_p
11823 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11824 || (type_dependent_expression_p
11825 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11827 return dependent_type_p (TREE_TYPE (type));
11830 /* -- a template-id in which either the template name is a template
11832 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11834 /* ... or any of the template arguments is a dependent type or
11835 an expression that is type-dependent or value-dependent. */
11836 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11837 && (any_dependent_template_arguments_p
11838 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11841 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11842 expression is not type-dependent, then it should already been
11844 if (TREE_CODE (type) == TYPEOF_TYPE)
11847 /* The standard does not specifically mention types that are local
11848 to template functions or local classes, but they should be
11849 considered dependent too. For example:
11851 template <int I> void f() {
11856 The size of `E' cannot be known until the value of `I' has been
11857 determined. Therefore, `E' must be considered dependent. */
11858 scope = TYPE_CONTEXT (type);
11859 if (scope && TYPE_P (scope))
11860 return dependent_type_p (scope);
11861 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11862 return type_dependent_expression_p (scope);
11864 /* Other types are non-dependent. */
11868 /* Returns TRUE if TYPE is dependent, in the sense of
11869 [temp.dep.type]. */
11872 dependent_type_p (tree type)
11874 /* If there are no template parameters in scope, then there can't be
11875 any dependent types. */
11876 if (!processing_template_decl)
11879 /* If the type is NULL, we have not computed a type for the entity
11880 in question; in that case, the type is dependent. */
11884 /* Erroneous types can be considered non-dependent. */
11885 if (type == error_mark_node)
11888 /* If we have not already computed the appropriate value for TYPE,
11890 if (!TYPE_DEPENDENT_P_VALID (type))
11892 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11893 TYPE_DEPENDENT_P_VALID (type) = 1;
11896 return TYPE_DEPENDENT_P (type);
11899 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11902 dependent_scope_ref_p (tree expression, bool criterion (tree))
11907 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
11909 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11912 scope = TREE_OPERAND (expression, 0);
11913 name = TREE_OPERAND (expression, 1);
11917 An id-expression is type-dependent if it contains a
11918 nested-name-specifier that contains a class-name that names a
11920 /* The suggested resolution to Core Issue 2 implies that if the
11921 qualifying type is the current class, then we must peek
11924 && currently_open_class (scope)
11925 && !criterion (name))
11927 if (dependent_type_p (scope))
11933 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11934 [temp.dep.constexpr] */
11937 value_dependent_expression_p (tree expression)
11939 if (!processing_template_decl)
11942 /* A name declared with a dependent type. */
11943 if (TREE_CODE (expression) == IDENTIFIER_NODE
11944 || (DECL_P (expression)
11945 && type_dependent_expression_p (expression)))
11947 /* A non-type template parameter. */
11948 if ((TREE_CODE (expression) == CONST_DECL
11949 && DECL_TEMPLATE_PARM_P (expression))
11950 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11952 /* A constant with integral or enumeration type and is initialized
11953 with an expression that is value-dependent. */
11954 if (TREE_CODE (expression) == VAR_DECL
11955 && DECL_INITIAL (expression)
11956 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11957 && value_dependent_expression_p (DECL_INITIAL (expression)))
11959 /* These expressions are value-dependent if the type to which the
11960 cast occurs is dependent or the expression being casted is
11961 value-dependent. */
11962 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11963 || TREE_CODE (expression) == STATIC_CAST_EXPR
11964 || TREE_CODE (expression) == CONST_CAST_EXPR
11965 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11966 || TREE_CODE (expression) == CAST_EXPR)
11968 tree type = TREE_TYPE (expression);
11969 if (dependent_type_p (type))
11971 /* A functional cast has a list of operands. */
11972 expression = TREE_OPERAND (expression, 0);
11975 /* If there are no operands, it must be an expression such
11976 as "int()". This should not happen for aggregate types
11977 because it would form non-constant expressions. */
11978 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
11982 if (TREE_CODE (expression) == TREE_LIST)
11986 if (value_dependent_expression_p (TREE_VALUE (expression)))
11988 expression = TREE_CHAIN (expression);
11990 while (expression);
11994 return value_dependent_expression_p (expression);
11996 /* A `sizeof' expression is value-dependent if the operand is
11998 if (TREE_CODE (expression) == SIZEOF_EXPR
11999 || TREE_CODE (expression) == ALIGNOF_EXPR)
12001 expression = TREE_OPERAND (expression, 0);
12002 if (TYPE_P (expression))
12003 return dependent_type_p (expression);
12004 return type_dependent_expression_p (expression);
12006 if (TREE_CODE (expression) == SCOPE_REF)
12007 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12008 if (TREE_CODE (expression) == COMPONENT_REF)
12009 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12010 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12011 /* A constant expression is value-dependent if any subexpression is
12012 value-dependent. */
12013 if (EXPR_P (expression))
12015 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12018 return (value_dependent_expression_p
12019 (TREE_OPERAND (expression, 0)));
12020 case tcc_comparison:
12022 return ((value_dependent_expression_p
12023 (TREE_OPERAND (expression, 0)))
12024 || (value_dependent_expression_p
12025 (TREE_OPERAND (expression, 1))));
12026 case tcc_expression:
12029 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12030 /* In some cases, some of the operands may be missing.
12031 (For example, in the case of PREDECREMENT_EXPR, the
12032 amount to increment by may be missing.) That doesn't
12033 make the expression dependent. */
12034 if (TREE_OPERAND (expression, i)
12035 && (value_dependent_expression_p
12036 (TREE_OPERAND (expression, i))))
12040 case tcc_reference:
12041 case tcc_statement:
12042 /* These cannot be value dependent. */
12046 gcc_unreachable ();
12050 /* The expression is not value-dependent. */
12054 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12055 [temp.dep.expr]. */
12058 type_dependent_expression_p (tree expression)
12060 if (!processing_template_decl)
12063 if (expression == error_mark_node)
12066 /* An unresolved name is always dependent. */
12067 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12070 /* Some expression forms are never type-dependent. */
12071 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12072 || TREE_CODE (expression) == SIZEOF_EXPR
12073 || TREE_CODE (expression) == ALIGNOF_EXPR
12074 || TREE_CODE (expression) == TYPEID_EXPR
12075 || TREE_CODE (expression) == DELETE_EXPR
12076 || TREE_CODE (expression) == VEC_DELETE_EXPR
12077 || TREE_CODE (expression) == THROW_EXPR)
12080 /* The types of these expressions depends only on the type to which
12081 the cast occurs. */
12082 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12083 || TREE_CODE (expression) == STATIC_CAST_EXPR
12084 || TREE_CODE (expression) == CONST_CAST_EXPR
12085 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12086 || TREE_CODE (expression) == CAST_EXPR)
12087 return dependent_type_p (TREE_TYPE (expression));
12089 /* The types of these expressions depends only on the type created
12090 by the expression. */
12091 if (TREE_CODE (expression) == NEW_EXPR
12092 || TREE_CODE (expression) == VEC_NEW_EXPR)
12094 /* For NEW_EXPR tree nodes created inside a template, either
12095 the object type itself or a TREE_LIST may appear as the
12097 tree type = TREE_OPERAND (expression, 1);
12098 if (TREE_CODE (type) == TREE_LIST)
12099 /* This is an array type. We need to check array dimensions
12101 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12102 || value_dependent_expression_p
12103 (TREE_OPERAND (TREE_VALUE (type), 1));
12105 return dependent_type_p (type);
12108 if (TREE_CODE (expression) == SCOPE_REF
12109 && dependent_scope_ref_p (expression,
12110 type_dependent_expression_p))
12113 if (TREE_CODE (expression) == FUNCTION_DECL
12114 && DECL_LANG_SPECIFIC (expression)
12115 && DECL_TEMPLATE_INFO (expression)
12116 && (any_dependent_template_arguments_p
12117 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12120 if (TREE_CODE (expression) == TEMPLATE_DECL
12121 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12124 if (TREE_TYPE (expression) == unknown_type_node)
12126 if (TREE_CODE (expression) == ADDR_EXPR)
12127 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12128 if (TREE_CODE (expression) == COMPONENT_REF
12129 || TREE_CODE (expression) == OFFSET_REF)
12131 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12133 expression = TREE_OPERAND (expression, 1);
12134 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12137 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12138 if (TREE_CODE (expression) == SCOPE_REF)
12141 if (TREE_CODE (expression) == BASELINK)
12142 expression = BASELINK_FUNCTIONS (expression);
12144 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12146 if (any_dependent_template_arguments_p
12147 (TREE_OPERAND (expression, 1)))
12149 expression = TREE_OPERAND (expression, 0);
12151 gcc_assert (TREE_CODE (expression) == OVERLOAD);
12155 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12157 expression = OVL_NEXT (expression);
12162 return (dependent_type_p (TREE_TYPE (expression)));
12165 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12166 contains a type-dependent expression. */
12169 any_type_dependent_arguments_p (tree args)
12173 tree arg = TREE_VALUE (args);
12175 if (type_dependent_expression_p (arg))
12177 args = TREE_CHAIN (args);
12182 /* Returns TRUE if the ARG (a template argument) is dependent. */
12185 dependent_template_arg_p (tree arg)
12187 if (!processing_template_decl)
12190 if (TREE_CODE (arg) == TEMPLATE_DECL
12191 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12192 return dependent_template_p (arg);
12193 else if (TYPE_P (arg))
12194 return dependent_type_p (arg);
12196 return (type_dependent_expression_p (arg)
12197 || value_dependent_expression_p (arg));
12200 /* Returns true if ARGS (a collection of template arguments) contains
12201 any dependent arguments. */
12204 any_dependent_template_arguments_p (tree args)
12212 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12214 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12215 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12216 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12223 /* Returns TRUE if the template TMPL is dependent. */
12226 dependent_template_p (tree tmpl)
12228 if (TREE_CODE (tmpl) == OVERLOAD)
12232 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12234 tmpl = OVL_CHAIN (tmpl);
12239 /* Template template parameters are dependent. */
12240 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12241 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12243 /* So are names that have not been looked up. */
12244 if (TREE_CODE (tmpl) == SCOPE_REF
12245 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12247 /* So are member templates of dependent classes. */
12248 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12249 return dependent_type_p (DECL_CONTEXT (tmpl));
12253 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12256 dependent_template_id_p (tree tmpl, tree args)
12258 return (dependent_template_p (tmpl)
12259 || any_dependent_template_arguments_p (args));
12262 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12263 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12264 can be found. Note that this function peers inside uninstantiated
12265 templates and therefore should be used only in extremely limited
12269 resolve_typename_type (tree type, bool only_current_p)
12277 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12279 scope = TYPE_CONTEXT (type);
12280 name = TYPE_IDENTIFIER (type);
12282 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12283 it first before we can figure out what NAME refers to. */
12284 if (TREE_CODE (scope) == TYPENAME_TYPE)
12285 scope = resolve_typename_type (scope, only_current_p);
12286 /* If we don't know what SCOPE refers to, then we cannot resolve the
12288 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12289 return error_mark_node;
12290 /* If the SCOPE is a template type parameter, we have no way of
12291 resolving the name. */
12292 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12294 /* If the SCOPE is not the current instantiation, there's no reason
12295 to look inside it. */
12296 if (only_current_p && !currently_open_class (scope))
12297 return error_mark_node;
12298 /* If SCOPE is a partial instantiation, it will not have a valid
12299 TYPE_FIELDS list, so use the original template. */
12300 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12301 /* Enter the SCOPE so that name lookup will be resolved as if we
12302 were in the class definition. In particular, SCOPE will no
12303 longer be considered a dependent type. */
12304 pushed_scope = push_scope (scope);
12305 /* Look up the declaration. */
12306 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12307 /* Obtain the set of qualifiers applied to the TYPE. */
12308 quals = cp_type_quals (type);
12309 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12310 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12312 type = error_mark_node;
12313 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12314 && TREE_CODE (decl) == TYPE_DECL)
12315 type = TREE_TYPE (decl);
12316 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12317 && DECL_CLASS_TEMPLATE_P (decl))
12321 /* Obtain the template and the arguments. */
12322 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12323 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12324 /* Instantiate the template. */
12325 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12326 /*entering_scope=*/0, tf_error | tf_user);
12329 type = error_mark_node;
12330 /* Qualify the resulting type. */
12331 if (type != error_mark_node && quals)
12332 type = cp_build_qualified_type (type, quals);
12333 /* Leave the SCOPE. */
12335 pop_scope (pushed_scope);
12340 /* EXPR is an expression which is not type-dependent. Return a proxy
12341 for EXPR that can be used to compute the types of larger
12342 expressions containing EXPR. */
12345 build_non_dependent_expr (tree expr)
12349 /* Preserve null pointer constants so that the type of things like
12350 "p == 0" where "p" is a pointer can be determined. */
12351 if (null_ptr_cst_p (expr))
12353 /* Preserve OVERLOADs; the functions must be available to resolve
12355 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12356 TREE_OPERAND (expr, 0) : expr);
12357 if (TREE_CODE (inner_expr) == OVERLOAD
12358 || TREE_CODE (inner_expr) == FUNCTION_DECL
12359 || TREE_CODE (inner_expr) == TEMPLATE_DECL
12360 || TREE_CODE (inner_expr) == TEMPLATE_ID_EXPR)
12362 /* There is no need to return a proxy for a variable. */
12363 if (TREE_CODE (expr) == VAR_DECL)
12365 /* Preserve string constants; conversions from string constants to
12366 "char *" are allowed, even though normally a "const char *"
12367 cannot be used to initialize a "char *". */
12368 if (TREE_CODE (expr) == STRING_CST)
12370 /* Preserve arithmetic constants, as an optimization -- there is no
12371 reason to create a new node. */
12372 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12374 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12375 There is at least one place where we want to know that a
12376 particular expression is a throw-expression: when checking a ?:
12377 expression, there are special rules if the second or third
12378 argument is a throw-expression. */
12379 if (TREE_CODE (expr) == THROW_EXPR)
12382 if (TREE_CODE (expr) == COND_EXPR)
12383 return build3 (COND_EXPR,
12385 TREE_OPERAND (expr, 0),
12386 (TREE_OPERAND (expr, 1)
12387 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12388 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12389 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12390 if (TREE_CODE (expr) == COMPOUND_EXPR
12391 && !COMPOUND_EXPR_OVERLOADED (expr))
12392 return build2 (COMPOUND_EXPR,
12394 TREE_OPERAND (expr, 0),
12395 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12397 /* Otherwise, build a NON_DEPENDENT_EXPR.
12399 REFERENCE_TYPEs are not stripped for expressions in templates
12400 because doing so would play havoc with mangling. Consider, for
12403 template <typename T> void f<T& g>() { g(); }
12405 In the body of "f", the expression for "g" will have
12406 REFERENCE_TYPE, even though the standard says that it should
12407 not. The reason is that we must preserve the syntactic form of
12408 the expression so that mangling (say) "f<g>" inside the body of
12409 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12411 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12414 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12415 Return a new TREE_LIST with the various arguments replaced with
12416 equivalent non-dependent expressions. */
12419 build_non_dependent_args (tree args)
12424 new_args = NULL_TREE;
12425 for (a = args; a; a = TREE_CHAIN (a))
12426 new_args = tree_cons (NULL_TREE,
12427 build_non_dependent_expr (TREE_VALUE (a)),
12429 return nreverse (new_args);
12432 #include "gt-cp-pt.h"