1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@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 3, 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 COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
38 #include "tree-dump.h"
39 #include "splay-tree.h"
40 #include "pointer-set.h"
42 /* The number of nested classes being processed. If we are not in the
43 scope of any class, this is zero. */
45 int current_class_depth;
47 /* In order to deal with nested classes, we keep a stack of classes.
48 The topmost entry is the innermost class, and is the entry at index
49 CURRENT_CLASS_DEPTH */
51 typedef struct class_stack_node {
52 /* The name of the class. */
55 /* The _TYPE node for the class. */
58 /* The access specifier pending for new declarations in the scope of
62 /* If were defining TYPE, the names used in this class. */
63 splay_tree names_used;
65 /* Nonzero if this class is no longer open, because of a call to
68 }* class_stack_node_t;
70 typedef struct vtbl_init_data_s
72 /* The base for which we're building initializers. */
74 /* The type of the most-derived type. */
76 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
77 unless ctor_vtbl_p is true. */
79 /* The negative-index vtable initializers built up so far. These
80 are in order from least negative index to most negative index. */
81 VEC(constructor_elt,gc) *inits;
82 /* The binfo for the virtual base for which we're building
83 vcall offset initializers. */
85 /* The functions in vbase for which we have already provided vcall
88 /* The vtable index of the next vcall or vbase offset. */
90 /* Nonzero if we are building the initializer for the primary
93 /* Nonzero if we are building the initializer for a construction
96 /* True when adding vcall offset entries to the vtable. False when
97 merely computing the indices. */
98 bool generate_vcall_entries;
101 /* The type of a function passed to walk_subobject_offsets. */
102 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
104 /* The stack itself. This is a dynamically resized array. The
105 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
106 static int current_class_stack_size;
107 static class_stack_node_t current_class_stack;
109 /* The size of the largest empty class seen in this translation unit. */
110 static GTY (()) tree sizeof_biggest_empty_class;
112 /* An array of all local classes present in this translation unit, in
113 declaration order. */
114 VEC(tree,gc) *local_classes;
116 static tree get_vfield_name (tree);
117 static void finish_struct_anon (tree);
118 static tree get_vtable_name (tree);
119 static tree get_basefndecls (tree, tree);
120 static int build_primary_vtable (tree, tree);
121 static int build_secondary_vtable (tree);
122 static void finish_vtbls (tree);
123 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
124 static void finish_struct_bits (tree);
125 static int alter_access (tree, tree, tree);
126 static void handle_using_decl (tree, tree);
127 static tree dfs_modify_vtables (tree, void *);
128 static tree modify_all_vtables (tree, tree);
129 static void determine_primary_bases (tree);
130 static void finish_struct_methods (tree);
131 static void maybe_warn_about_overly_private_class (tree);
132 static int method_name_cmp (const void *, const void *);
133 static int resort_method_name_cmp (const void *, const void *);
134 static void add_implicitly_declared_members (tree, int, int);
135 static tree fixed_type_or_null (tree, int *, int *);
136 static tree build_simple_base_path (tree expr, tree binfo);
137 static tree build_vtbl_ref_1 (tree, tree);
138 static void build_vtbl_initializer (tree, tree, tree, tree, int *,
139 VEC(constructor_elt,gc) **);
140 static int count_fields (tree);
141 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
142 static bool check_bitfield_decl (tree);
143 static void check_field_decl (tree, tree, int *, int *, int *);
144 static void check_field_decls (tree, tree *, int *, int *);
145 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
146 static void build_base_fields (record_layout_info, splay_tree, tree *);
147 static void check_methods (tree);
148 static void remove_zero_width_bit_fields (tree);
149 static void check_bases (tree, int *, int *);
150 static void check_bases_and_members (tree);
151 static tree create_vtable_ptr (tree, tree *);
152 static void include_empty_classes (record_layout_info);
153 static void layout_class_type (tree, tree *);
154 static void propagate_binfo_offsets (tree, tree);
155 static void layout_virtual_bases (record_layout_info, splay_tree);
156 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
157 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
158 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
159 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
160 static void add_vcall_offset (tree, tree, vtbl_init_data *);
161 static void layout_vtable_decl (tree, int);
162 static tree dfs_find_final_overrider_pre (tree, void *);
163 static tree dfs_find_final_overrider_post (tree, void *);
164 static tree find_final_overrider (tree, tree, tree);
165 static int make_new_vtable (tree, tree);
166 static tree get_primary_binfo (tree);
167 static int maybe_indent_hierarchy (FILE *, int, int);
168 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
169 static void dump_class_hierarchy (tree);
170 static void dump_class_hierarchy_1 (FILE *, int, tree);
171 static void dump_array (FILE *, tree);
172 static void dump_vtable (tree, tree, tree);
173 static void dump_vtt (tree, tree);
174 static void dump_thunk (FILE *, int, tree);
175 static tree build_vtable (tree, tree, tree);
176 static void initialize_vtable (tree, VEC(constructor_elt,gc) *);
177 static void layout_nonempty_base_or_field (record_layout_info,
178 tree, tree, splay_tree);
179 static tree end_of_class (tree, int);
180 static bool layout_empty_base (record_layout_info, tree, tree, splay_tree);
181 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree,
182 VEC(constructor_elt,gc) **);
183 static void dfs_accumulate_vtbl_inits (tree, tree, tree, tree, tree,
184 VEC(constructor_elt,gc) **);
185 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
186 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
187 static void clone_constructors_and_destructors (tree);
188 static tree build_clone (tree, tree);
189 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
190 static void build_ctor_vtbl_group (tree, tree);
191 static void build_vtt (tree);
192 static tree binfo_ctor_vtable (tree);
193 static void build_vtt_inits (tree, tree, VEC(constructor_elt,gc) **, tree *);
194 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
195 static tree dfs_fixup_binfo_vtbls (tree, void *);
196 static int record_subobject_offset (tree, tree, splay_tree);
197 static int check_subobject_offset (tree, tree, splay_tree);
198 static int walk_subobject_offsets (tree, subobject_offset_fn,
199 tree, splay_tree, tree, int);
200 static void record_subobject_offsets (tree, tree, splay_tree, bool);
201 static int layout_conflict_p (tree, tree, splay_tree, int);
202 static int splay_tree_compare_integer_csts (splay_tree_key k1,
204 static void warn_about_ambiguous_bases (tree);
205 static bool type_requires_array_cookie (tree);
206 static bool contains_empty_class_p (tree);
207 static bool base_derived_from (tree, tree);
208 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
209 static tree end_of_base (tree);
210 static tree get_vcall_index (tree, tree);
212 /* Variables shared between class.c and call.c. */
214 #ifdef GATHER_STATISTICS
216 int n_vtable_entries = 0;
217 int n_vtable_searches = 0;
218 int n_vtable_elems = 0;
219 int n_convert_harshness = 0;
220 int n_compute_conversion_costs = 0;
221 int n_inner_fields_searched = 0;
224 /* Convert to or from a base subobject. EXPR is an expression of type
225 `A' or `A*', an expression of type `B' or `B*' is returned. To
226 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
227 the B base instance within A. To convert base A to derived B, CODE
228 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
229 In this latter case, A must not be a morally virtual base of B.
230 NONNULL is true if EXPR is known to be non-NULL (this is only
231 needed when EXPR is of pointer type). CV qualifiers are preserved
235 build_base_path (enum tree_code code,
239 tsubst_flags_t complain)
241 tree v_binfo = NULL_TREE;
242 tree d_binfo = NULL_TREE;
246 tree null_test = NULL;
247 tree ptr_target_type;
249 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
250 bool has_empty = false;
253 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
254 return error_mark_node;
256 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
259 if (is_empty_class (BINFO_TYPE (probe)))
261 if (!v_binfo && BINFO_VIRTUAL_P (probe))
265 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
267 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
269 gcc_assert ((code == MINUS_EXPR
270 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
271 || (code == PLUS_EXPR
272 && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
274 if (binfo == d_binfo)
278 if (code == MINUS_EXPR && v_binfo)
280 if (complain & tf_error)
281 error ("cannot convert from base %qT to derived type %qT via "
282 "virtual base %qT", BINFO_TYPE (binfo), BINFO_TYPE (d_binfo),
283 BINFO_TYPE (v_binfo));
284 return error_mark_node;
288 /* This must happen before the call to save_expr. */
289 expr = cp_build_addr_expr (expr, complain);
291 expr = mark_rvalue_use (expr);
293 offset = BINFO_OFFSET (binfo);
294 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
295 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
296 /* TARGET_TYPE has been extracted from BINFO, and, is therefore always
297 cv-unqualified. Extract the cv-qualifiers from EXPR so that the
298 expression returned matches the input. */
299 target_type = cp_build_qualified_type
300 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
301 ptr_target_type = build_pointer_type (target_type);
303 /* Do we need to look in the vtable for the real offset? */
304 virtual_access = (v_binfo && fixed_type_p <= 0);
306 /* Don't bother with the calculations inside sizeof; they'll ICE if the
307 source type is incomplete and the pointer value doesn't matter. */
308 if (cp_unevaluated_operand != 0)
310 expr = build_nop (ptr_target_type, expr);
312 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, RO_NULL);
316 /* Do we need to check for a null pointer? */
317 if (want_pointer && !nonnull)
319 /* If we know the conversion will not actually change the value
320 of EXPR, then we can avoid testing the expression for NULL.
321 We have to avoid generating a COMPONENT_REF for a base class
322 field, because other parts of the compiler know that such
323 expressions are always non-NULL. */
324 if (!virtual_access && integer_zerop (offset))
325 return build_nop (ptr_target_type, expr);
326 null_test = error_mark_node;
329 /* Protect against multiple evaluation if necessary. */
330 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
331 expr = save_expr (expr);
333 /* Now that we've saved expr, build the real null test. */
336 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
337 null_test = fold_build2_loc (input_location, NE_EXPR, boolean_type_node,
341 /* If this is a simple base reference, express it as a COMPONENT_REF. */
342 if (code == PLUS_EXPR && !virtual_access
343 /* We don't build base fields for empty bases, and they aren't very
344 interesting to the optimizers anyway. */
347 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
348 expr = build_simple_base_path (expr, binfo);
350 expr = build_address (expr);
351 target_type = TREE_TYPE (expr);
357 /* Going via virtual base V_BINFO. We need the static offset
358 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
359 V_BINFO. That offset is an entry in D_BINFO's vtable. */
362 if (fixed_type_p < 0 && in_base_initializer)
364 /* In a base member initializer, we cannot rely on the
365 vtable being set up. We have to indirect via the
369 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
370 t = build_pointer_type (t);
371 v_offset = convert (t, current_vtt_parm);
372 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
375 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, RO_NULL,
377 TREE_TYPE (TREE_TYPE (expr)));
379 v_offset = fold_build_pointer_plus (v_offset, BINFO_VPTR_FIELD (v_binfo));
380 v_offset = build1 (NOP_EXPR,
381 build_pointer_type (ptrdiff_type_node),
383 v_offset = cp_build_indirect_ref (v_offset, RO_NULL, complain);
384 TREE_CONSTANT (v_offset) = 1;
386 offset = convert_to_integer (ptrdiff_type_node,
387 size_diffop_loc (input_location, offset,
388 BINFO_OFFSET (v_binfo)));
390 if (!integer_zerop (offset))
391 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
393 if (fixed_type_p < 0)
394 /* Negative fixed_type_p means this is a constructor or destructor;
395 virtual base layout is fixed in in-charge [cd]tors, but not in
397 offset = build3 (COND_EXPR, ptrdiff_type_node,
398 build2 (EQ_EXPR, boolean_type_node,
399 current_in_charge_parm, integer_zero_node),
401 convert_to_integer (ptrdiff_type_node,
402 BINFO_OFFSET (binfo)));
408 target_type = ptr_target_type;
410 expr = build1 (NOP_EXPR, ptr_target_type, expr);
412 if (!integer_zerop (offset))
414 offset = fold_convert (sizetype, offset);
415 if (code == MINUS_EXPR)
416 offset = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, offset);
417 expr = fold_build_pointer_plus (expr, offset);
423 expr = cp_build_indirect_ref (expr, RO_NULL, complain);
427 expr = fold_build3_loc (input_location, COND_EXPR, target_type, null_test, expr,
428 build_zero_cst (target_type));
433 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
434 Perform a derived-to-base conversion by recursively building up a
435 sequence of COMPONENT_REFs to the appropriate base fields. */
438 build_simple_base_path (tree expr, tree binfo)
440 tree type = BINFO_TYPE (binfo);
441 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
444 if (d_binfo == NULL_TREE)
448 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
450 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
451 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
452 an lvalue in the front end; only _DECLs and _REFs are lvalues
454 temp = unary_complex_lvalue (ADDR_EXPR, expr);
456 expr = cp_build_indirect_ref (temp, RO_NULL, tf_warning_or_error);
462 expr = build_simple_base_path (expr, d_binfo);
464 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
465 field; field = DECL_CHAIN (field))
466 /* Is this the base field created by build_base_field? */
467 if (TREE_CODE (field) == FIELD_DECL
468 && DECL_FIELD_IS_BASE (field)
469 && TREE_TYPE (field) == type)
471 /* We don't use build_class_member_access_expr here, as that
472 has unnecessary checks, and more importantly results in
473 recursive calls to dfs_walk_once. */
474 int type_quals = cp_type_quals (TREE_TYPE (expr));
476 expr = build3 (COMPONENT_REF,
477 cp_build_qualified_type (type, type_quals),
478 expr, field, NULL_TREE);
479 expr = fold_if_not_in_template (expr);
481 /* Mark the expression const or volatile, as appropriate.
482 Even though we've dealt with the type above, we still have
483 to mark the expression itself. */
484 if (type_quals & TYPE_QUAL_CONST)
485 TREE_READONLY (expr) = 1;
486 if (type_quals & TYPE_QUAL_VOLATILE)
487 TREE_THIS_VOLATILE (expr) = 1;
492 /* Didn't find the base field?!? */
496 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
497 type is a class type or a pointer to a class type. In the former
498 case, TYPE is also a class type; in the latter it is another
499 pointer type. If CHECK_ACCESS is true, an error message is emitted
500 if TYPE is inaccessible. If OBJECT has pointer type, the value is
501 assumed to be non-NULL. */
504 convert_to_base (tree object, tree type, bool check_access, bool nonnull,
505 tsubst_flags_t complain)
511 if (TYPE_PTR_P (TREE_TYPE (object)))
513 object_type = TREE_TYPE (TREE_TYPE (object));
514 type = TREE_TYPE (type);
517 object_type = TREE_TYPE (object);
519 access = check_access ? ba_check : ba_unique;
520 if (!(complain & tf_error))
522 binfo = lookup_base (object_type, type,
525 if (!binfo || binfo == error_mark_node)
526 return error_mark_node;
528 return build_base_path (PLUS_EXPR, object, binfo, nonnull, complain);
531 /* EXPR is an expression with unqualified class type. BASE is a base
532 binfo of that class type. Returns EXPR, converted to the BASE
533 type. This function assumes that EXPR is the most derived class;
534 therefore virtual bases can be found at their static offsets. */
537 convert_to_base_statically (tree expr, tree base)
541 expr_type = TREE_TYPE (expr);
542 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
544 /* We use fold_build2 and fold_convert below to simplify the trees
545 provided to the optimizers. It is not safe to call these functions
546 when processing a template because they do not handle C++-specific
548 gcc_assert (!processing_template_decl);
549 expr = cp_build_addr_expr (expr, tf_warning_or_error);
550 if (!integer_zerop (BINFO_OFFSET (base)))
551 expr = fold_build_pointer_plus_loc (input_location,
552 expr, BINFO_OFFSET (base));
553 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
554 expr = build_fold_indirect_ref_loc (input_location, expr);
562 build_vfield_ref (tree datum, tree type)
564 tree vfield, vcontext;
566 if (datum == error_mark_node)
567 return error_mark_node;
569 /* First, convert to the requested type. */
570 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
571 datum = convert_to_base (datum, type, /*check_access=*/false,
572 /*nonnull=*/true, tf_warning_or_error);
574 /* Second, the requested type may not be the owner of its own vptr.
575 If not, convert to the base class that owns it. We cannot use
576 convert_to_base here, because VCONTEXT may appear more than once
577 in the inheritance hierarchy of TYPE, and thus direct conversion
578 between the types may be ambiguous. Following the path back up
579 one step at a time via primary bases avoids the problem. */
580 vfield = TYPE_VFIELD (type);
581 vcontext = DECL_CONTEXT (vfield);
582 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
584 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
585 type = TREE_TYPE (datum);
588 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
591 /* Given an object INSTANCE, return an expression which yields the
592 vtable element corresponding to INDEX. There are many special
593 cases for INSTANCE which we take care of here, mainly to avoid
594 creating extra tree nodes when we don't have to. */
597 build_vtbl_ref_1 (tree instance, tree idx)
600 tree vtbl = NULL_TREE;
602 /* Try to figure out what a reference refers to, and
603 access its virtual function table directly. */
606 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
608 tree basetype = non_reference (TREE_TYPE (instance));
610 if (fixed_type && !cdtorp)
612 tree binfo = lookup_base (fixed_type, basetype,
613 ba_unique | ba_quiet, NULL);
615 vtbl = unshare_expr (BINFO_VTABLE (binfo));
619 vtbl = build_vfield_ref (instance, basetype);
621 aref = build_array_ref (input_location, vtbl, idx);
622 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
628 build_vtbl_ref (tree instance, tree idx)
630 tree aref = build_vtbl_ref_1 (instance, idx);
635 /* Given a stable object pointer INSTANCE_PTR, return an expression which
636 yields a function pointer corresponding to vtable element INDEX. */
639 build_vfn_ref (tree instance_ptr, tree idx)
643 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, RO_NULL,
644 tf_warning_or_error),
647 /* When using function descriptors, the address of the
648 vtable entry is treated as a function pointer. */
649 if (TARGET_VTABLE_USES_DESCRIPTORS)
650 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
651 cp_build_addr_expr (aref, tf_warning_or_error));
653 /* Remember this as a method reference, for later devirtualization. */
654 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
659 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
660 for the given TYPE. */
663 get_vtable_name (tree type)
665 return mangle_vtbl_for_type (type);
668 /* DECL is an entity associated with TYPE, like a virtual table or an
669 implicitly generated constructor. Determine whether or not DECL
670 should have external or internal linkage at the object file
671 level. This routine does not deal with COMDAT linkage and other
672 similar complexities; it simply sets TREE_PUBLIC if it possible for
673 entities in other translation units to contain copies of DECL, in
677 set_linkage_according_to_type (tree type ATTRIBUTE_UNUSED, tree decl)
679 TREE_PUBLIC (decl) = 1;
680 determine_visibility (decl);
683 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
684 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
685 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
688 build_vtable (tree class_type, tree name, tree vtable_type)
692 decl = build_lang_decl (VAR_DECL, name, vtable_type);
693 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
694 now to avoid confusion in mangle_decl. */
695 SET_DECL_ASSEMBLER_NAME (decl, name);
696 DECL_CONTEXT (decl) = class_type;
697 DECL_ARTIFICIAL (decl) = 1;
698 TREE_STATIC (decl) = 1;
699 TREE_READONLY (decl) = 1;
700 DECL_VIRTUAL_P (decl) = 1;
701 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
702 DECL_VTABLE_OR_VTT_P (decl) = 1;
703 /* At one time the vtable info was grabbed 2 words at a time. This
704 fails on sparc unless you have 8-byte alignment. (tiemann) */
705 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
707 set_linkage_according_to_type (class_type, decl);
708 /* The vtable has not been defined -- yet. */
709 DECL_EXTERNAL (decl) = 1;
710 DECL_NOT_REALLY_EXTERN (decl) = 1;
712 /* Mark the VAR_DECL node representing the vtable itself as a
713 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
714 is rather important that such things be ignored because any
715 effort to actually generate DWARF for them will run into
716 trouble when/if we encounter code like:
719 struct S { virtual void member (); };
721 because the artificial declaration of the vtable itself (as
722 manufactured by the g++ front end) will say that the vtable is
723 a static member of `S' but only *after* the debug output for
724 the definition of `S' has already been output. This causes
725 grief because the DWARF entry for the definition of the vtable
726 will try to refer back to an earlier *declaration* of the
727 vtable as a static member of `S' and there won't be one. We
728 might be able to arrange to have the "vtable static member"
729 attached to the member list for `S' before the debug info for
730 `S' get written (which would solve the problem) but that would
731 require more intrusive changes to the g++ front end. */
732 DECL_IGNORED_P (decl) = 1;
737 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
738 or even complete. If this does not exist, create it. If COMPLETE is
739 nonzero, then complete the definition of it -- that will render it
740 impossible to actually build the vtable, but is useful to get at those
741 which are known to exist in the runtime. */
744 get_vtable_decl (tree type, int complete)
748 if (CLASSTYPE_VTABLES (type))
749 return CLASSTYPE_VTABLES (type);
751 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
752 CLASSTYPE_VTABLES (type) = decl;
756 DECL_EXTERNAL (decl) = 1;
757 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
763 /* Build the primary virtual function table for TYPE. If BINFO is
764 non-NULL, build the vtable starting with the initial approximation
765 that it is the same as the one which is the head of the association
766 list. Returns a nonzero value if a new vtable is actually
770 build_primary_vtable (tree binfo, tree type)
775 decl = get_vtable_decl (type, /*complete=*/0);
779 if (BINFO_NEW_VTABLE_MARKED (binfo))
780 /* We have already created a vtable for this base, so there's
781 no need to do it again. */
784 virtuals = copy_list (BINFO_VIRTUALS (binfo));
785 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
786 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
787 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
791 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
792 virtuals = NULL_TREE;
795 #ifdef GATHER_STATISTICS
797 n_vtable_elems += list_length (virtuals);
800 /* Initialize the association list for this type, based
801 on our first approximation. */
802 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
803 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
804 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
808 /* Give BINFO a new virtual function table which is initialized
809 with a skeleton-copy of its original initialization. The only
810 entry that changes is the `delta' entry, so we can really
811 share a lot of structure.
813 FOR_TYPE is the most derived type which caused this table to
816 Returns nonzero if we haven't met BINFO before.
818 The order in which vtables are built (by calling this function) for
819 an object must remain the same, otherwise a binary incompatibility
823 build_secondary_vtable (tree binfo)
825 if (BINFO_NEW_VTABLE_MARKED (binfo))
826 /* We already created a vtable for this base. There's no need to
830 /* Remember that we've created a vtable for this BINFO, so that we
831 don't try to do so again. */
832 SET_BINFO_NEW_VTABLE_MARKED (binfo);
834 /* Make fresh virtual list, so we can smash it later. */
835 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
837 /* Secondary vtables are laid out as part of the same structure as
838 the primary vtable. */
839 BINFO_VTABLE (binfo) = NULL_TREE;
843 /* Create a new vtable for BINFO which is the hierarchy dominated by
844 T. Return nonzero if we actually created a new vtable. */
847 make_new_vtable (tree t, tree binfo)
849 if (binfo == TYPE_BINFO (t))
850 /* In this case, it is *type*'s vtable we are modifying. We start
851 with the approximation that its vtable is that of the
852 immediate base class. */
853 return build_primary_vtable (binfo, t);
855 /* This is our very own copy of `basetype' to play with. Later,
856 we will fill in all the virtual functions that override the
857 virtual functions in these base classes which are not defined
858 by the current type. */
859 return build_secondary_vtable (binfo);
862 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
863 (which is in the hierarchy dominated by T) list FNDECL as its
864 BV_FN. DELTA is the required constant adjustment from the `this'
865 pointer where the vtable entry appears to the `this' required when
866 the function is actually called. */
869 modify_vtable_entry (tree t,
879 if (fndecl != BV_FN (v)
880 || !tree_int_cst_equal (delta, BV_DELTA (v)))
882 /* We need a new vtable for BINFO. */
883 if (make_new_vtable (t, binfo))
885 /* If we really did make a new vtable, we also made a copy
886 of the BINFO_VIRTUALS list. Now, we have to find the
887 corresponding entry in that list. */
888 *virtuals = BINFO_VIRTUALS (binfo);
889 while (BV_FN (*virtuals) != BV_FN (v))
890 *virtuals = TREE_CHAIN (*virtuals);
894 BV_DELTA (v) = delta;
895 BV_VCALL_INDEX (v) = NULL_TREE;
901 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
902 the USING_DECL naming METHOD. Returns true if the method could be
903 added to the method vec. */
906 add_method (tree type, tree method, tree using_decl)
910 bool template_conv_p = false;
912 VEC(tree,gc) *method_vec;
914 bool insert_p = false;
918 if (method == error_mark_node)
921 complete_p = COMPLETE_TYPE_P (type);
922 conv_p = DECL_CONV_FN_P (method);
924 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
925 && DECL_TEMPLATE_CONV_FN_P (method));
927 method_vec = CLASSTYPE_METHOD_VEC (type);
930 /* Make a new method vector. We start with 8 entries. We must
931 allocate at least two (for constructors and destructors), and
932 we're going to end up with an assignment operator at some
934 method_vec = VEC_alloc (tree, gc, 8);
935 /* Create slots for constructors and destructors. */
936 VEC_quick_push (tree, method_vec, NULL_TREE);
937 VEC_quick_push (tree, method_vec, NULL_TREE);
938 CLASSTYPE_METHOD_VEC (type) = method_vec;
941 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
942 grok_special_member_properties (method);
944 /* Constructors and destructors go in special slots. */
945 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
946 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
947 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
949 slot = CLASSTYPE_DESTRUCTOR_SLOT;
951 if (TYPE_FOR_JAVA (type))
953 if (!DECL_ARTIFICIAL (method))
954 error ("Java class %qT cannot have a destructor", type);
955 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
956 error ("Java class %qT cannot have an implicit non-trivial "
966 /* See if we already have an entry with this name. */
967 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
968 VEC_iterate (tree, method_vec, slot, m);
974 if (TREE_CODE (m) == TEMPLATE_DECL
975 && DECL_TEMPLATE_CONV_FN_P (m))
979 if (conv_p && !DECL_CONV_FN_P (m))
981 if (DECL_NAME (m) == DECL_NAME (method))
987 && !DECL_CONV_FN_P (m)
988 && DECL_NAME (m) > DECL_NAME (method))
992 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
994 /* Check to see if we've already got this method. */
995 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
997 tree fn = OVL_CURRENT (fns);
1003 if (TREE_CODE (fn) != TREE_CODE (method))
1006 /* [over.load] Member function declarations with the
1007 same name and the same parameter types cannot be
1008 overloaded if any of them is a static member
1009 function declaration.
1011 [namespace.udecl] When a using-declaration brings names
1012 from a base class into a derived class scope, member
1013 functions in the derived class override and/or hide member
1014 functions with the same name and parameter types in a base
1015 class (rather than conflicting). */
1016 fn_type = TREE_TYPE (fn);
1017 method_type = TREE_TYPE (method);
1018 parms1 = TYPE_ARG_TYPES (fn_type);
1019 parms2 = TYPE_ARG_TYPES (method_type);
1021 /* Compare the quals on the 'this' parm. Don't compare
1022 the whole types, as used functions are treated as
1023 coming from the using class in overload resolution. */
1024 if (! DECL_STATIC_FUNCTION_P (fn)
1025 && ! DECL_STATIC_FUNCTION_P (method)
1026 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1027 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1028 && (cp_type_quals (TREE_TYPE (TREE_VALUE (parms1)))
1029 != cp_type_quals (TREE_TYPE (TREE_VALUE (parms2)))))
1032 /* For templates, the return type and template parameters
1033 must be identical. */
1034 if (TREE_CODE (fn) == TEMPLATE_DECL
1035 && (!same_type_p (TREE_TYPE (fn_type),
1036 TREE_TYPE (method_type))
1037 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1038 DECL_TEMPLATE_PARMS (method))))
1041 if (! DECL_STATIC_FUNCTION_P (fn))
1042 parms1 = TREE_CHAIN (parms1);
1043 if (! DECL_STATIC_FUNCTION_P (method))
1044 parms2 = TREE_CHAIN (parms2);
1046 if (compparms (parms1, parms2)
1047 && (!DECL_CONV_FN_P (fn)
1048 || same_type_p (TREE_TYPE (fn_type),
1049 TREE_TYPE (method_type))))
1053 if (DECL_CONTEXT (fn) == type)
1054 /* Defer to the local function. */
1056 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1057 error ("repeated using declaration %q+D", using_decl);
1059 error ("using declaration %q+D conflicts with a previous using declaration",
1064 error ("%q+#D cannot be overloaded", method);
1065 error ("with %q+#D", fn);
1068 /* We don't call duplicate_decls here to merge the
1069 declarations because that will confuse things if the
1070 methods have inline definitions. In particular, we
1071 will crash while processing the definitions. */
1076 /* A class should never have more than one destructor. */
1077 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1080 /* Add the new binding. */
1081 overload = build_overload (method, current_fns);
1084 TYPE_HAS_CONVERSION (type) = 1;
1085 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1086 push_class_level_binding (DECL_NAME (method), overload);
1092 /* We only expect to add few methods in the COMPLETE_P case, so
1093 just make room for one more method in that case. */
1095 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1097 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1099 CLASSTYPE_METHOD_VEC (type) = method_vec;
1100 if (slot == VEC_length (tree, method_vec))
1101 VEC_quick_push (tree, method_vec, overload);
1103 VEC_quick_insert (tree, method_vec, slot, overload);
1106 /* Replace the current slot. */
1107 VEC_replace (tree, method_vec, slot, overload);
1111 /* Subroutines of finish_struct. */
1113 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1114 legit, otherwise return 0. */
1117 alter_access (tree t, tree fdecl, tree access)
1121 if (!DECL_LANG_SPECIFIC (fdecl))
1122 retrofit_lang_decl (fdecl);
1124 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1126 elem = purpose_member (t, DECL_ACCESS (fdecl));
1129 if (TREE_VALUE (elem) != access)
1131 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1132 error ("conflicting access specifications for method"
1133 " %q+D, ignored", TREE_TYPE (fdecl));
1135 error ("conflicting access specifications for field %qE, ignored",
1140 /* They're changing the access to the same thing they changed
1141 it to before. That's OK. */
1147 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1148 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1154 /* Process the USING_DECL, which is a member of T. */
1157 handle_using_decl (tree using_decl, tree t)
1159 tree decl = USING_DECL_DECLS (using_decl);
1160 tree name = DECL_NAME (using_decl);
1162 = TREE_PRIVATE (using_decl) ? access_private_node
1163 : TREE_PROTECTED (using_decl) ? access_protected_node
1164 : access_public_node;
1165 tree flist = NULL_TREE;
1168 gcc_assert (!processing_template_decl && decl);
1170 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1173 if (is_overloaded_fn (old_value))
1174 old_value = OVL_CURRENT (old_value);
1176 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1179 old_value = NULL_TREE;
1182 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1184 if (is_overloaded_fn (decl))
1189 else if (is_overloaded_fn (old_value))
1192 /* It's OK to use functions from a base when there are functions with
1193 the same name already present in the current class. */;
1196 error ("%q+D invalid in %q#T", using_decl, t);
1197 error (" because of local method %q+#D with same name",
1198 OVL_CURRENT (old_value));
1202 else if (!DECL_ARTIFICIAL (old_value))
1204 error ("%q+D invalid in %q#T", using_decl, t);
1205 error (" because of local member %q+#D with same name", old_value);
1209 /* Make type T see field decl FDECL with access ACCESS. */
1211 for (; flist; flist = OVL_NEXT (flist))
1213 add_method (t, OVL_CURRENT (flist), using_decl);
1214 alter_access (t, OVL_CURRENT (flist), access);
1217 alter_access (t, decl, access);
1220 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1221 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1222 properties of the bases. */
1225 check_bases (tree t,
1226 int* cant_have_const_ctor_p,
1227 int* no_const_asn_ref_p)
1230 int seen_non_virtual_nearly_empty_base_p;
1233 tree field = NULL_TREE;
1235 seen_non_virtual_nearly_empty_base_p = 0;
1237 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1238 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
1239 if (TREE_CODE (field) == FIELD_DECL)
1242 for (binfo = TYPE_BINFO (t), i = 0;
1243 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1245 tree basetype = TREE_TYPE (base_binfo);
1247 gcc_assert (COMPLETE_TYPE_P (basetype));
1249 if (CLASSTYPE_FINAL (basetype))
1250 error ("cannot derive from %<final%> base %qT in derived type %qT",
1253 /* If any base class is non-literal, so is the derived class. */
1254 if (!CLASSTYPE_LITERAL_P (basetype))
1255 CLASSTYPE_LITERAL_P (t) = false;
1257 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1258 here because the case of virtual functions but non-virtual
1259 dtor is handled in finish_struct_1. */
1260 if (!TYPE_POLYMORPHIC_P (basetype))
1261 warning (OPT_Weffc__,
1262 "base class %q#T has a non-virtual destructor", basetype);
1264 /* If the base class doesn't have copy constructors or
1265 assignment operators that take const references, then the
1266 derived class cannot have such a member automatically
1268 if (TYPE_HAS_COPY_CTOR (basetype)
1269 && ! TYPE_HAS_CONST_COPY_CTOR (basetype))
1270 *cant_have_const_ctor_p = 1;
1271 if (TYPE_HAS_COPY_ASSIGN (basetype)
1272 && !TYPE_HAS_CONST_COPY_ASSIGN (basetype))
1273 *no_const_asn_ref_p = 1;
1275 if (BINFO_VIRTUAL_P (base_binfo))
1276 /* A virtual base does not effect nearly emptiness. */
1278 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1280 if (seen_non_virtual_nearly_empty_base_p)
1281 /* And if there is more than one nearly empty base, then the
1282 derived class is not nearly empty either. */
1283 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1285 /* Remember we've seen one. */
1286 seen_non_virtual_nearly_empty_base_p = 1;
1288 else if (!is_empty_class (basetype))
1289 /* If the base class is not empty or nearly empty, then this
1290 class cannot be nearly empty. */
1291 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1293 /* A lot of properties from the bases also apply to the derived
1295 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1296 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1297 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1298 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
1299 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (basetype)
1300 || !TYPE_HAS_COPY_ASSIGN (basetype));
1301 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (basetype)
1302 || !TYPE_HAS_COPY_CTOR (basetype));
1303 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t)
1304 |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (basetype);
1305 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (basetype);
1306 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1307 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1308 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1309 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
1310 || TYPE_HAS_COMPLEX_DFLT (basetype));
1312 /* A standard-layout class is a class that:
1314 * has no non-standard-layout base classes, */
1315 CLASSTYPE_NON_STD_LAYOUT (t) |= CLASSTYPE_NON_STD_LAYOUT (basetype);
1316 if (!CLASSTYPE_NON_STD_LAYOUT (t))
1319 /* ...has no base classes of the same type as the first non-static
1321 if (field && DECL_CONTEXT (field) == t
1322 && (same_type_ignoring_top_level_qualifiers_p
1323 (TREE_TYPE (field), basetype)))
1324 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1326 /* ...either has no non-static data members in the most-derived
1327 class and at most one base class with non-static data
1328 members, or has no base classes with non-static data
1330 for (basefield = TYPE_FIELDS (basetype); basefield;
1331 basefield = DECL_CHAIN (basefield))
1332 if (TREE_CODE (basefield) == FIELD_DECL)
1335 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
1344 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1345 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1346 that have had a nearly-empty virtual primary base stolen by some
1347 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1351 determine_primary_bases (tree t)
1354 tree primary = NULL_TREE;
1355 tree type_binfo = TYPE_BINFO (t);
1358 /* Determine the primary bases of our bases. */
1359 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1360 base_binfo = TREE_CHAIN (base_binfo))
1362 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1364 /* See if we're the non-virtual primary of our inheritance
1366 if (!BINFO_VIRTUAL_P (base_binfo))
1368 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1369 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1372 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1373 BINFO_TYPE (parent_primary)))
1374 /* We are the primary binfo. */
1375 BINFO_PRIMARY_P (base_binfo) = 1;
1377 /* Determine if we have a virtual primary base, and mark it so.
1379 if (primary && BINFO_VIRTUAL_P (primary))
1381 tree this_primary = copied_binfo (primary, base_binfo);
1383 if (BINFO_PRIMARY_P (this_primary))
1384 /* Someone already claimed this base. */
1385 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1390 BINFO_PRIMARY_P (this_primary) = 1;
1391 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1393 /* A virtual binfo might have been copied from within
1394 another hierarchy. As we're about to use it as a
1395 primary base, make sure the offsets match. */
1396 delta = size_diffop_loc (input_location,
1398 BINFO_OFFSET (base_binfo)),
1400 BINFO_OFFSET (this_primary)));
1402 propagate_binfo_offsets (this_primary, delta);
1407 /* First look for a dynamic direct non-virtual base. */
1408 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1410 tree basetype = BINFO_TYPE (base_binfo);
1412 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1414 primary = base_binfo;
1419 /* A "nearly-empty" virtual base class can be the primary base
1420 class, if no non-virtual polymorphic base can be found. Look for
1421 a nearly-empty virtual dynamic base that is not already a primary
1422 base of something in the hierarchy. If there is no such base,
1423 just pick the first nearly-empty virtual base. */
1425 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1426 base_binfo = TREE_CHAIN (base_binfo))
1427 if (BINFO_VIRTUAL_P (base_binfo)
1428 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1430 if (!BINFO_PRIMARY_P (base_binfo))
1432 /* Found one that is not primary. */
1433 primary = base_binfo;
1437 /* Remember the first candidate. */
1438 primary = base_binfo;
1442 /* If we've got a primary base, use it. */
1445 tree basetype = BINFO_TYPE (primary);
1447 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1448 if (BINFO_PRIMARY_P (primary))
1449 /* We are stealing a primary base. */
1450 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1451 BINFO_PRIMARY_P (primary) = 1;
1452 if (BINFO_VIRTUAL_P (primary))
1456 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1457 /* A virtual binfo might have been copied from within
1458 another hierarchy. As we're about to use it as a primary
1459 base, make sure the offsets match. */
1460 delta = size_diffop_loc (input_location, ssize_int (0),
1461 convert (ssizetype, BINFO_OFFSET (primary)));
1463 propagate_binfo_offsets (primary, delta);
1466 primary = TYPE_BINFO (basetype);
1468 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1469 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1470 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1474 /* Update the variant types of T. */
1477 fixup_type_variants (tree t)
1484 for (variants = TYPE_NEXT_VARIANT (t);
1486 variants = TYPE_NEXT_VARIANT (variants))
1488 /* These fields are in the _TYPE part of the node, not in
1489 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1490 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1491 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1492 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1493 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1495 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1497 TYPE_BINFO (variants) = TYPE_BINFO (t);
1499 /* Copy whatever these are holding today. */
1500 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1501 TYPE_METHODS (variants) = TYPE_METHODS (t);
1502 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1506 /* Early variant fixups: we apply attributes at the beginning of the class
1507 definition, and we need to fix up any variants that have already been
1508 made via elaborated-type-specifier so that check_qualified_type works. */
1511 fixup_attribute_variants (tree t)
1518 for (variants = TYPE_NEXT_VARIANT (t);
1520 variants = TYPE_NEXT_VARIANT (variants))
1522 /* These are the two fields that check_qualified_type looks at and
1523 are affected by attributes. */
1524 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1525 TYPE_ALIGN (variants) = TYPE_ALIGN (t);
1529 /* Set memoizing fields and bits of T (and its variants) for later
1533 finish_struct_bits (tree t)
1535 /* Fix up variants (if any). */
1536 fixup_type_variants (t);
1538 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1539 /* For a class w/o baseclasses, 'finish_struct' has set
1540 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1541 Similarly for a class whose base classes do not have vtables.
1542 When neither of these is true, we might have removed abstract
1543 virtuals (by providing a definition), added some (by declaring
1544 new ones), or redeclared ones from a base class. We need to
1545 recalculate what's really an abstract virtual at this point (by
1546 looking in the vtables). */
1547 get_pure_virtuals (t);
1549 /* If this type has a copy constructor or a destructor, force its
1550 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1551 nonzero. This will cause it to be passed by invisible reference
1552 and prevent it from being returned in a register. */
1553 if (type_has_nontrivial_copy_init (t)
1554 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1557 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1558 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1560 SET_TYPE_MODE (variants, BLKmode);
1561 TREE_ADDRESSABLE (variants) = 1;
1566 /* Issue warnings about T having private constructors, but no friends,
1569 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1570 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1571 non-private static member functions. */
1574 maybe_warn_about_overly_private_class (tree t)
1576 int has_member_fn = 0;
1577 int has_nonprivate_method = 0;
1580 if (!warn_ctor_dtor_privacy
1581 /* If the class has friends, those entities might create and
1582 access instances, so we should not warn. */
1583 || (CLASSTYPE_FRIEND_CLASSES (t)
1584 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1585 /* We will have warned when the template was declared; there's
1586 no need to warn on every instantiation. */
1587 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1588 /* There's no reason to even consider warning about this
1592 /* We only issue one warning, if more than one applies, because
1593 otherwise, on code like:
1596 // Oops - forgot `public:'
1602 we warn several times about essentially the same problem. */
1604 /* Check to see if all (non-constructor, non-destructor) member
1605 functions are private. (Since there are no friends or
1606 non-private statics, we can't ever call any of the private member
1608 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
1609 /* We're not interested in compiler-generated methods; they don't
1610 provide any way to call private members. */
1611 if (!DECL_ARTIFICIAL (fn))
1613 if (!TREE_PRIVATE (fn))
1615 if (DECL_STATIC_FUNCTION_P (fn))
1616 /* A non-private static member function is just like a
1617 friend; it can create and invoke private member
1618 functions, and be accessed without a class
1622 has_nonprivate_method = 1;
1623 /* Keep searching for a static member function. */
1625 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1629 if (!has_nonprivate_method && has_member_fn)
1631 /* There are no non-private methods, and there's at least one
1632 private member function that isn't a constructor or
1633 destructor. (If all the private members are
1634 constructors/destructors we want to use the code below that
1635 issues error messages specifically referring to
1636 constructors/destructors.) */
1638 tree binfo = TYPE_BINFO (t);
1640 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1641 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1643 has_nonprivate_method = 1;
1646 if (!has_nonprivate_method)
1648 warning (OPT_Wctor_dtor_privacy,
1649 "all member functions in class %qT are private", t);
1654 /* Even if some of the member functions are non-private, the class
1655 won't be useful for much if all the constructors or destructors
1656 are private: such an object can never be created or destroyed. */
1657 fn = CLASSTYPE_DESTRUCTORS (t);
1658 if (fn && TREE_PRIVATE (fn))
1660 warning (OPT_Wctor_dtor_privacy,
1661 "%q#T only defines a private destructor and has no friends",
1666 /* Warn about classes that have private constructors and no friends. */
1667 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1668 /* Implicitly generated constructors are always public. */
1669 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1670 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1672 int nonprivate_ctor = 0;
1674 /* If a non-template class does not define a copy
1675 constructor, one is defined for it, enabling it to avoid
1676 this warning. For a template class, this does not
1677 happen, and so we would normally get a warning on:
1679 template <class T> class C { private: C(); };
1681 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
1682 complete non-template or fully instantiated classes have this
1684 if (!TYPE_HAS_COPY_CTOR (t))
1685 nonprivate_ctor = 1;
1687 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1689 tree ctor = OVL_CURRENT (fn);
1690 /* Ideally, we wouldn't count copy constructors (or, in
1691 fact, any constructor that takes an argument of the
1692 class type as a parameter) because such things cannot
1693 be used to construct an instance of the class unless
1694 you already have one. But, for now at least, we're
1696 if (! TREE_PRIVATE (ctor))
1698 nonprivate_ctor = 1;
1703 if (nonprivate_ctor == 0)
1705 warning (OPT_Wctor_dtor_privacy,
1706 "%q#T only defines private constructors and has no friends",
1714 gt_pointer_operator new_value;
1718 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1721 method_name_cmp (const void* m1_p, const void* m2_p)
1723 const tree *const m1 = (const tree *) m1_p;
1724 const tree *const m2 = (const tree *) m2_p;
1726 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1728 if (*m1 == NULL_TREE)
1730 if (*m2 == NULL_TREE)
1732 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1737 /* This routine compares two fields like method_name_cmp but using the
1738 pointer operator in resort_field_decl_data. */
1741 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1743 const tree *const m1 = (const tree *) m1_p;
1744 const tree *const m2 = (const tree *) m2_p;
1745 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1747 if (*m1 == NULL_TREE)
1749 if (*m2 == NULL_TREE)
1752 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1753 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1754 resort_data.new_value (&d1, resort_data.cookie);
1755 resort_data.new_value (&d2, resort_data.cookie);
1762 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1765 resort_type_method_vec (void* obj,
1766 void* orig_obj ATTRIBUTE_UNUSED ,
1767 gt_pointer_operator new_value,
1770 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1771 int len = VEC_length (tree, method_vec);
1775 /* The type conversion ops have to live at the front of the vec, so we
1777 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1778 VEC_iterate (tree, method_vec, slot, fn);
1780 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1785 resort_data.new_value = new_value;
1786 resort_data.cookie = cookie;
1787 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1788 resort_method_name_cmp);
1792 /* Warn about duplicate methods in fn_fields.
1794 Sort methods that are not special (i.e., constructors, destructors,
1795 and type conversion operators) so that we can find them faster in
1799 finish_struct_methods (tree t)
1802 VEC(tree,gc) *method_vec;
1805 method_vec = CLASSTYPE_METHOD_VEC (t);
1809 len = VEC_length (tree, method_vec);
1811 /* Clear DECL_IN_AGGR_P for all functions. */
1812 for (fn_fields = TYPE_METHODS (t); fn_fields;
1813 fn_fields = DECL_CHAIN (fn_fields))
1814 DECL_IN_AGGR_P (fn_fields) = 0;
1816 /* Issue warnings about private constructors and such. If there are
1817 no methods, then some public defaults are generated. */
1818 maybe_warn_about_overly_private_class (t);
1820 /* The type conversion ops have to live at the front of the vec, so we
1822 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1823 VEC_iterate (tree, method_vec, slot, fn_fields);
1825 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1828 qsort (VEC_address (tree, method_vec) + slot,
1829 len-slot, sizeof (tree), method_name_cmp);
1832 /* Make BINFO's vtable have N entries, including RTTI entries,
1833 vbase and vcall offsets, etc. Set its type and call the back end
1837 layout_vtable_decl (tree binfo, int n)
1842 atype = build_array_of_n_type (vtable_entry_type, n);
1843 layout_type (atype);
1845 /* We may have to grow the vtable. */
1846 vtable = get_vtbl_decl_for_binfo (binfo);
1847 if (!same_type_p (TREE_TYPE (vtable), atype))
1849 TREE_TYPE (vtable) = atype;
1850 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1851 layout_decl (vtable, 0);
1855 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1856 have the same signature. */
1859 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1861 /* One destructor overrides another if they are the same kind of
1863 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1864 && special_function_p (base_fndecl) == special_function_p (fndecl))
1866 /* But a non-destructor never overrides a destructor, nor vice
1867 versa, nor do different kinds of destructors override
1868 one-another. For example, a complete object destructor does not
1869 override a deleting destructor. */
1870 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1873 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1874 || (DECL_CONV_FN_P (fndecl)
1875 && DECL_CONV_FN_P (base_fndecl)
1876 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1877 DECL_CONV_FN_TYPE (base_fndecl))))
1879 tree types, base_types;
1880 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1881 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1882 if ((cp_type_quals (TREE_TYPE (TREE_VALUE (base_types)))
1883 == cp_type_quals (TREE_TYPE (TREE_VALUE (types))))
1884 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1890 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1894 base_derived_from (tree derived, tree base)
1898 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1900 if (probe == derived)
1902 else if (BINFO_VIRTUAL_P (probe))
1903 /* If we meet a virtual base, we can't follow the inheritance
1904 any more. See if the complete type of DERIVED contains
1905 such a virtual base. */
1906 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1912 typedef struct find_final_overrider_data_s {
1913 /* The function for which we are trying to find a final overrider. */
1915 /* The base class in which the function was declared. */
1916 tree declaring_base;
1917 /* The candidate overriders. */
1919 /* Path to most derived. */
1920 VEC(tree,heap) *path;
1921 } find_final_overrider_data;
1923 /* Add the overrider along the current path to FFOD->CANDIDATES.
1924 Returns true if an overrider was found; false otherwise. */
1927 dfs_find_final_overrider_1 (tree binfo,
1928 find_final_overrider_data *ffod,
1933 /* If BINFO is not the most derived type, try a more derived class.
1934 A definition there will overrider a definition here. */
1938 if (dfs_find_final_overrider_1
1939 (VEC_index (tree, ffod->path, depth), ffod, depth))
1943 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1946 tree *candidate = &ffod->candidates;
1948 /* Remove any candidates overridden by this new function. */
1951 /* If *CANDIDATE overrides METHOD, then METHOD
1952 cannot override anything else on the list. */
1953 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1955 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1956 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1957 *candidate = TREE_CHAIN (*candidate);
1959 candidate = &TREE_CHAIN (*candidate);
1962 /* Add the new function. */
1963 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1970 /* Called from find_final_overrider via dfs_walk. */
1973 dfs_find_final_overrider_pre (tree binfo, void *data)
1975 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1977 if (binfo == ffod->declaring_base)
1978 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1979 VEC_safe_push (tree, heap, ffod->path, binfo);
1985 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1987 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1988 VEC_pop (tree, ffod->path);
1993 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1994 FN and whose TREE_VALUE is the binfo for the base where the
1995 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1996 DERIVED) is the base object in which FN is declared. */
1999 find_final_overrider (tree derived, tree binfo, tree fn)
2001 find_final_overrider_data ffod;
2003 /* Getting this right is a little tricky. This is valid:
2005 struct S { virtual void f (); };
2006 struct T { virtual void f (); };
2007 struct U : public S, public T { };
2009 even though calling `f' in `U' is ambiguous. But,
2011 struct R { virtual void f(); };
2012 struct S : virtual public R { virtual void f (); };
2013 struct T : virtual public R { virtual void f (); };
2014 struct U : public S, public T { };
2016 is not -- there's no way to decide whether to put `S::f' or
2017 `T::f' in the vtable for `R'.
2019 The solution is to look at all paths to BINFO. If we find
2020 different overriders along any two, then there is a problem. */
2021 if (DECL_THUNK_P (fn))
2022 fn = THUNK_TARGET (fn);
2024 /* Determine the depth of the hierarchy. */
2026 ffod.declaring_base = binfo;
2027 ffod.candidates = NULL_TREE;
2028 ffod.path = VEC_alloc (tree, heap, 30);
2030 dfs_walk_all (derived, dfs_find_final_overrider_pre,
2031 dfs_find_final_overrider_post, &ffod);
2033 VEC_free (tree, heap, ffod.path);
2035 /* If there was no winner, issue an error message. */
2036 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
2037 return error_mark_node;
2039 return ffod.candidates;
2042 /* Return the index of the vcall offset for FN when TYPE is used as a
2046 get_vcall_index (tree fn, tree type)
2048 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
2052 FOR_EACH_VEC_ELT (tree_pair_s, indices, ix, p)
2053 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2054 || same_signature_p (fn, p->purpose))
2057 /* There should always be an appropriate index. */
2061 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2062 dominated by T. FN is the old function; VIRTUALS points to the
2063 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2064 of that entry in the list. */
2067 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2075 tree overrider_fn, overrider_target;
2076 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2077 tree over_return, base_return;
2080 /* Find the nearest primary base (possibly binfo itself) which defines
2081 this function; this is the class the caller will convert to when
2082 calling FN through BINFO. */
2083 for (b = binfo; ; b = get_primary_binfo (b))
2086 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2089 /* The nearest definition is from a lost primary. */
2090 if (BINFO_LOST_PRIMARY_P (b))
2095 /* Find the final overrider. */
2096 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2097 if (overrider == error_mark_node)
2099 error ("no unique final overrider for %qD in %qT", target_fn, t);
2102 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2104 /* Check for adjusting covariant return types. */
2105 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2106 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2108 if (POINTER_TYPE_P (over_return)
2109 && TREE_CODE (over_return) == TREE_CODE (base_return)
2110 && CLASS_TYPE_P (TREE_TYPE (over_return))
2111 && CLASS_TYPE_P (TREE_TYPE (base_return))
2112 /* If the overrider is invalid, don't even try. */
2113 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2115 /* If FN is a covariant thunk, we must figure out the adjustment
2116 to the final base FN was converting to. As OVERRIDER_TARGET might
2117 also be converting to the return type of FN, we have to
2118 combine the two conversions here. */
2119 tree fixed_offset, virtual_offset;
2121 over_return = TREE_TYPE (over_return);
2122 base_return = TREE_TYPE (base_return);
2124 if (DECL_THUNK_P (fn))
2126 gcc_assert (DECL_RESULT_THUNK_P (fn));
2127 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2128 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2131 fixed_offset = virtual_offset = NULL_TREE;
2134 /* Find the equivalent binfo within the return type of the
2135 overriding function. We will want the vbase offset from
2137 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2139 else if (!same_type_ignoring_top_level_qualifiers_p
2140 (over_return, base_return))
2142 /* There was no existing virtual thunk (which takes
2143 precedence). So find the binfo of the base function's
2144 return type within the overriding function's return type.
2145 We cannot call lookup base here, because we're inside a
2146 dfs_walk, and will therefore clobber the BINFO_MARKED
2147 flags. Fortunately we know the covariancy is valid (it
2148 has already been checked), so we can just iterate along
2149 the binfos, which have been chained in inheritance graph
2150 order. Of course it is lame that we have to repeat the
2151 search here anyway -- we should really be caching pieces
2152 of the vtable and avoiding this repeated work. */
2153 tree thunk_binfo, base_binfo;
2155 /* Find the base binfo within the overriding function's
2156 return type. We will always find a thunk_binfo, except
2157 when the covariancy is invalid (which we will have
2158 already diagnosed). */
2159 for (base_binfo = TYPE_BINFO (base_return),
2160 thunk_binfo = TYPE_BINFO (over_return);
2162 thunk_binfo = TREE_CHAIN (thunk_binfo))
2163 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2164 BINFO_TYPE (base_binfo)))
2167 /* See if virtual inheritance is involved. */
2168 for (virtual_offset = thunk_binfo;
2170 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2171 if (BINFO_VIRTUAL_P (virtual_offset))
2175 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2177 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2181 /* We convert via virtual base. Adjust the fixed
2182 offset to be from there. */
2184 size_diffop (offset,
2186 BINFO_OFFSET (virtual_offset)));
2189 /* There was an existing fixed offset, this must be
2190 from the base just converted to, and the base the
2191 FN was thunking to. */
2192 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2194 fixed_offset = offset;
2198 if (fixed_offset || virtual_offset)
2199 /* Replace the overriding function with a covariant thunk. We
2200 will emit the overriding function in its own slot as
2202 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2203 fixed_offset, virtual_offset);
2206 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2207 !DECL_THUNK_P (fn));
2209 /* If we need a covariant thunk, then we may need to adjust first_defn.
2210 The ABI specifies that the thunks emitted with a function are
2211 determined by which bases the function overrides, so we need to be
2212 sure that we're using a thunk for some overridden base; even if we
2213 know that the necessary this adjustment is zero, there may not be an
2214 appropriate zero-this-adjusment thunk for us to use since thunks for
2215 overriding virtual bases always use the vcall offset.
2217 Furthermore, just choosing any base that overrides this function isn't
2218 quite right, as this slot won't be used for calls through a type that
2219 puts a covariant thunk here. Calling the function through such a type
2220 will use a different slot, and that slot is the one that determines
2221 the thunk emitted for that base.
2223 So, keep looking until we find the base that we're really overriding
2224 in this slot: the nearest primary base that doesn't use a covariant
2225 thunk in this slot. */
2226 if (overrider_target != overrider_fn)
2228 if (BINFO_TYPE (b) == DECL_CONTEXT (overrider_target))
2229 /* We already know that the overrider needs a covariant thunk. */
2230 b = get_primary_binfo (b);
2231 for (; ; b = get_primary_binfo (b))
2233 tree main_binfo = TYPE_BINFO (BINFO_TYPE (b));
2234 tree bv = chain_index (ix, BINFO_VIRTUALS (main_binfo));
2235 if (!DECL_THUNK_P (TREE_VALUE (bv)))
2237 if (BINFO_LOST_PRIMARY_P (b))
2243 /* Assume that we will produce a thunk that convert all the way to
2244 the final overrider, and not to an intermediate virtual base. */
2245 virtual_base = NULL_TREE;
2247 /* See if we can convert to an intermediate virtual base first, and then
2248 use the vcall offset located there to finish the conversion. */
2249 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2251 /* If we find the final overrider, then we can stop
2253 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2254 BINFO_TYPE (TREE_VALUE (overrider))))
2257 /* If we find a virtual base, and we haven't yet found the
2258 overrider, then there is a virtual base between the
2259 declaring base (first_defn) and the final overrider. */
2260 if (BINFO_VIRTUAL_P (b))
2267 /* Compute the constant adjustment to the `this' pointer. The
2268 `this' pointer, when this function is called, will point at BINFO
2269 (or one of its primary bases, which are at the same offset). */
2271 /* The `this' pointer needs to be adjusted from the declaration to
2272 the nearest virtual base. */
2273 delta = size_diffop_loc (input_location,
2274 convert (ssizetype, BINFO_OFFSET (virtual_base)),
2275 convert (ssizetype, BINFO_OFFSET (first_defn)));
2277 /* If the nearest definition is in a lost primary, we don't need an
2278 entry in our vtable. Except possibly in a constructor vtable,
2279 if we happen to get our primary back. In that case, the offset
2280 will be zero, as it will be a primary base. */
2281 delta = size_zero_node;
2283 /* The `this' pointer needs to be adjusted from pointing to
2284 BINFO to pointing at the base where the final overrider
2286 delta = size_diffop_loc (input_location,
2288 BINFO_OFFSET (TREE_VALUE (overrider))),
2289 convert (ssizetype, BINFO_OFFSET (binfo)));
2291 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2294 BV_VCALL_INDEX (*virtuals)
2295 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2297 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2299 BV_LOST_PRIMARY (*virtuals) = lost;
2302 /* Called from modify_all_vtables via dfs_walk. */
2305 dfs_modify_vtables (tree binfo, void* data)
2307 tree t = (tree) data;
2312 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2313 /* A base without a vtable needs no modification, and its bases
2314 are uninteresting. */
2315 return dfs_skip_bases;
2317 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2318 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2319 /* Don't do the primary vtable, if it's new. */
2322 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2323 /* There's no need to modify the vtable for a non-virtual primary
2324 base; we're not going to use that vtable anyhow. We do still
2325 need to do this for virtual primary bases, as they could become
2326 non-primary in a construction vtable. */
2329 make_new_vtable (t, binfo);
2331 /* Now, go through each of the virtual functions in the virtual
2332 function table for BINFO. Find the final overrider, and update
2333 the BINFO_VIRTUALS list appropriately. */
2334 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2335 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2337 ix++, virtuals = TREE_CHAIN (virtuals),
2338 old_virtuals = TREE_CHAIN (old_virtuals))
2339 update_vtable_entry_for_fn (t,
2341 BV_FN (old_virtuals),
2347 /* Update all of the primary and secondary vtables for T. Create new
2348 vtables as required, and initialize their RTTI information. Each
2349 of the functions in VIRTUALS is declared in T and may override a
2350 virtual function from a base class; find and modify the appropriate
2351 entries to point to the overriding functions. Returns a list, in
2352 declaration order, of the virtual functions that are declared in T,
2353 but do not appear in the primary base class vtable, and which
2354 should therefore be appended to the end of the vtable for T. */
2357 modify_all_vtables (tree t, tree virtuals)
2359 tree binfo = TYPE_BINFO (t);
2362 /* Update all of the vtables. */
2363 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2365 /* Add virtual functions not already in our primary vtable. These
2366 will be both those introduced by this class, and those overridden
2367 from secondary bases. It does not include virtuals merely
2368 inherited from secondary bases. */
2369 for (fnsp = &virtuals; *fnsp; )
2371 tree fn = TREE_VALUE (*fnsp);
2373 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2374 || DECL_VINDEX (fn) == error_mark_node)
2376 /* We don't need to adjust the `this' pointer when
2377 calling this function. */
2378 BV_DELTA (*fnsp) = integer_zero_node;
2379 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2381 /* This is a function not already in our vtable. Keep it. */
2382 fnsp = &TREE_CHAIN (*fnsp);
2385 /* We've already got an entry for this function. Skip it. */
2386 *fnsp = TREE_CHAIN (*fnsp);
2392 /* Get the base virtual function declarations in T that have the
2396 get_basefndecls (tree name, tree t)
2399 tree base_fndecls = NULL_TREE;
2400 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2403 /* Find virtual functions in T with the indicated NAME. */
2404 i = lookup_fnfields_1 (t, name);
2406 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2408 methods = OVL_NEXT (methods))
2410 tree method = OVL_CURRENT (methods);
2412 if (TREE_CODE (method) == FUNCTION_DECL
2413 && DECL_VINDEX (method))
2414 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2418 return base_fndecls;
2420 for (i = 0; i < n_baseclasses; i++)
2422 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2423 base_fndecls = chainon (get_basefndecls (name, basetype),
2427 return base_fndecls;
2430 /* If this declaration supersedes the declaration of
2431 a method declared virtual in the base class, then
2432 mark this field as being virtual as well. */
2435 check_for_override (tree decl, tree ctype)
2437 bool overrides_found = false;
2438 if (TREE_CODE (decl) == TEMPLATE_DECL)
2439 /* In [temp.mem] we have:
2441 A specialization of a member function template does not
2442 override a virtual function from a base class. */
2444 if ((DECL_DESTRUCTOR_P (decl)
2445 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2446 || DECL_CONV_FN_P (decl))
2447 && look_for_overrides (ctype, decl)
2448 && !DECL_STATIC_FUNCTION_P (decl))
2449 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2450 the error_mark_node so that we know it is an overriding
2453 DECL_VINDEX (decl) = decl;
2454 overrides_found = true;
2457 if (DECL_VIRTUAL_P (decl))
2459 if (!DECL_VINDEX (decl))
2460 DECL_VINDEX (decl) = error_mark_node;
2461 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2462 if (DECL_DESTRUCTOR_P (decl))
2463 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (ctype) = true;
2465 else if (DECL_FINAL_P (decl))
2466 error ("%q+#D marked final, but is not virtual", decl);
2467 if (DECL_OVERRIDE_P (decl) && !overrides_found)
2468 error ("%q+#D marked override, but does not override", decl);
2471 /* Warn about hidden virtual functions that are not overridden in t.
2472 We know that constructors and destructors don't apply. */
2475 warn_hidden (tree t)
2477 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2481 /* We go through each separately named virtual function. */
2482 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2483 VEC_iterate (tree, method_vec, i, fns);
2494 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2495 have the same name. Figure out what name that is. */
2496 name = DECL_NAME (OVL_CURRENT (fns));
2497 /* There are no possibly hidden functions yet. */
2498 base_fndecls = NULL_TREE;
2499 /* Iterate through all of the base classes looking for possibly
2500 hidden functions. */
2501 for (binfo = TYPE_BINFO (t), j = 0;
2502 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2504 tree basetype = BINFO_TYPE (base_binfo);
2505 base_fndecls = chainon (get_basefndecls (name, basetype),
2509 /* If there are no functions to hide, continue. */
2513 /* Remove any overridden functions. */
2514 for (fn = fns; fn; fn = OVL_NEXT (fn))
2516 fndecl = OVL_CURRENT (fn);
2517 if (DECL_VINDEX (fndecl))
2519 tree *prev = &base_fndecls;
2522 /* If the method from the base class has the same
2523 signature as the method from the derived class, it
2524 has been overridden. */
2525 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2526 *prev = TREE_CHAIN (*prev);
2528 prev = &TREE_CHAIN (*prev);
2532 /* Now give a warning for all base functions without overriders,
2533 as they are hidden. */
2534 while (base_fndecls)
2536 /* Here we know it is a hider, and no overrider exists. */
2537 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2538 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2539 base_fndecls = TREE_CHAIN (base_fndecls);
2544 /* Check for things that are invalid. There are probably plenty of other
2545 things we should check for also. */
2548 finish_struct_anon (tree t)
2552 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
2554 if (TREE_STATIC (field))
2556 if (TREE_CODE (field) != FIELD_DECL)
2559 if (DECL_NAME (field) == NULL_TREE
2560 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2562 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2563 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2564 for (; elt; elt = DECL_CHAIN (elt))
2566 /* We're generally only interested in entities the user
2567 declared, but we also find nested classes by noticing
2568 the TYPE_DECL that we create implicitly. You're
2569 allowed to put one anonymous union inside another,
2570 though, so we explicitly tolerate that. We use
2571 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2572 we also allow unnamed types used for defining fields. */
2573 if (DECL_ARTIFICIAL (elt)
2574 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2575 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2578 if (TREE_CODE (elt) != FIELD_DECL)
2581 permerror (input_location, "%q+#D invalid; an anonymous union can "
2582 "only have non-static data members", elt);
2584 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2585 "only have non-static data members", elt);
2589 if (TREE_PRIVATE (elt))
2592 permerror (input_location, "private member %q+#D in anonymous union", elt);
2594 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2596 else if (TREE_PROTECTED (elt))
2599 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2601 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2604 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2605 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2611 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2612 will be used later during class template instantiation.
2613 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2614 a non-static member data (FIELD_DECL), a member function
2615 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2616 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2617 When FRIEND_P is nonzero, T is either a friend class
2618 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2619 (FUNCTION_DECL, TEMPLATE_DECL). */
2622 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2624 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2625 if (CLASSTYPE_TEMPLATE_INFO (type))
2626 CLASSTYPE_DECL_LIST (type)
2627 = tree_cons (friend_p ? NULL_TREE : type,
2628 t, CLASSTYPE_DECL_LIST (type));
2631 /* This function is called from declare_virt_assop_and_dtor via
2634 DATA is a type that direcly or indirectly inherits the base
2635 represented by BINFO. If BINFO contains a virtual assignment [copy
2636 assignment or move assigment] operator or a virtual constructor,
2637 declare that function in DATA if it hasn't been already declared. */
2640 dfs_declare_virt_assop_and_dtor (tree binfo, void *data)
2642 tree bv, fn, t = (tree)data;
2643 tree opname = ansi_assopname (NOP_EXPR);
2645 gcc_assert (t && CLASS_TYPE_P (t));
2646 gcc_assert (binfo && TREE_CODE (binfo) == TREE_BINFO);
2648 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2649 /* A base without a vtable needs no modification, and its bases
2650 are uninteresting. */
2651 return dfs_skip_bases;
2653 if (BINFO_PRIMARY_P (binfo))
2654 /* If this is a primary base, then we have already looked at the
2655 virtual functions of its vtable. */
2658 for (bv = BINFO_VIRTUALS (binfo); bv; bv = TREE_CHAIN (bv))
2662 if (DECL_NAME (fn) == opname)
2664 if (CLASSTYPE_LAZY_COPY_ASSIGN (t))
2665 lazily_declare_fn (sfk_copy_assignment, t);
2666 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
2667 lazily_declare_fn (sfk_move_assignment, t);
2669 else if (DECL_DESTRUCTOR_P (fn)
2670 && CLASSTYPE_LAZY_DESTRUCTOR (t))
2671 lazily_declare_fn (sfk_destructor, t);
2677 /* If the class type T has a direct or indirect base that contains a
2678 virtual assignment operator or a virtual destructor, declare that
2679 function in T if it hasn't been already declared. */
2682 declare_virt_assop_and_dtor (tree t)
2684 if (!(TYPE_POLYMORPHIC_P (t)
2685 && (CLASSTYPE_LAZY_COPY_ASSIGN (t)
2686 || CLASSTYPE_LAZY_MOVE_ASSIGN (t)
2687 || CLASSTYPE_LAZY_DESTRUCTOR (t))))
2690 dfs_walk_all (TYPE_BINFO (t),
2691 dfs_declare_virt_assop_and_dtor,
2695 /* Create default constructors, assignment operators, and so forth for
2696 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2697 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2698 the class cannot have a default constructor, copy constructor
2699 taking a const reference argument, or an assignment operator taking
2700 a const reference, respectively. */
2703 add_implicitly_declared_members (tree t,
2704 int cant_have_const_cctor,
2705 int cant_have_const_assignment)
2708 if (!CLASSTYPE_DESTRUCTORS (t))
2710 /* In general, we create destructors lazily. */
2711 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2713 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2714 && TYPE_FOR_JAVA (t))
2715 /* But if this is a Java class, any non-trivial destructor is
2716 invalid, even if compiler-generated. Therefore, if the
2717 destructor is non-trivial we create it now. */
2718 lazily_declare_fn (sfk_destructor, t);
2723 If there is no user-declared constructor for a class, a default
2724 constructor is implicitly declared. */
2725 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2727 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2728 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2729 if (cxx_dialect >= cxx0x)
2730 TYPE_HAS_CONSTEXPR_CTOR (t)
2731 /* This might force the declaration. */
2732 = type_has_constexpr_default_constructor (t);
2737 If a class definition does not explicitly declare a copy
2738 constructor, one is declared implicitly. */
2739 if (! TYPE_HAS_COPY_CTOR (t) && ! TYPE_FOR_JAVA (t))
2741 TYPE_HAS_COPY_CTOR (t) = 1;
2742 TYPE_HAS_CONST_COPY_CTOR (t) = !cant_have_const_cctor;
2743 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2744 if (cxx_dialect >= cxx0x && !type_has_move_constructor (t))
2745 CLASSTYPE_LAZY_MOVE_CTOR (t) = 1;
2748 /* If there is no assignment operator, one will be created if and
2749 when it is needed. For now, just record whether or not the type
2750 of the parameter to the assignment operator will be a const or
2751 non-const reference. */
2752 if (!TYPE_HAS_COPY_ASSIGN (t) && !TYPE_FOR_JAVA (t))
2754 TYPE_HAS_COPY_ASSIGN (t) = 1;
2755 TYPE_HAS_CONST_COPY_ASSIGN (t) = !cant_have_const_assignment;
2756 CLASSTYPE_LAZY_COPY_ASSIGN (t) = 1;
2757 if (cxx_dialect >= cxx0x && !type_has_move_assign (t))
2758 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 1;
2761 /* We can't be lazy about declaring functions that might override
2762 a virtual function from a base class. */
2763 declare_virt_assop_and_dtor (t);
2766 /* Subroutine of finish_struct_1. Recursively count the number of fields
2767 in TYPE, including anonymous union members. */
2770 count_fields (tree fields)
2774 for (x = fields; x; x = DECL_CHAIN (x))
2776 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2777 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2784 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2785 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2788 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2791 for (x = fields; x; x = DECL_CHAIN (x))
2793 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2794 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2796 field_vec->elts[idx++] = x;
2801 /* FIELD is a bit-field. We are finishing the processing for its
2802 enclosing type. Issue any appropriate messages and set appropriate
2803 flags. Returns false if an error has been diagnosed. */
2806 check_bitfield_decl (tree field)
2808 tree type = TREE_TYPE (field);
2811 /* Extract the declared width of the bitfield, which has been
2812 temporarily stashed in DECL_INITIAL. */
2813 w = DECL_INITIAL (field);
2814 gcc_assert (w != NULL_TREE);
2815 /* Remove the bit-field width indicator so that the rest of the
2816 compiler does not treat that value as an initializer. */
2817 DECL_INITIAL (field) = NULL_TREE;
2819 /* Detect invalid bit-field type. */
2820 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
2822 error ("bit-field %q+#D with non-integral type", field);
2823 w = error_mark_node;
2827 location_t loc = input_location;
2828 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2831 /* detect invalid field size. */
2832 input_location = DECL_SOURCE_LOCATION (field);
2833 w = cxx_constant_value (w);
2834 input_location = loc;
2836 if (TREE_CODE (w) != INTEGER_CST)
2838 error ("bit-field %q+D width not an integer constant", field);
2839 w = error_mark_node;
2841 else if (tree_int_cst_sgn (w) < 0)
2843 error ("negative width in bit-field %q+D", field);
2844 w = error_mark_node;
2846 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2848 error ("zero width for bit-field %q+D", field);
2849 w = error_mark_node;
2851 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2852 && TREE_CODE (type) != ENUMERAL_TYPE
2853 && TREE_CODE (type) != BOOLEAN_TYPE)
2854 warning (0, "width of %q+D exceeds its type", field);
2855 else if (TREE_CODE (type) == ENUMERAL_TYPE
2856 && (0 > (compare_tree_int
2857 (w, TYPE_PRECISION (ENUM_UNDERLYING_TYPE (type))))))
2858 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2861 if (w != error_mark_node)
2863 DECL_SIZE (field) = convert (bitsizetype, w);
2864 DECL_BIT_FIELD (field) = 1;
2869 /* Non-bit-fields are aligned for their type. */
2870 DECL_BIT_FIELD (field) = 0;
2871 CLEAR_DECL_C_BIT_FIELD (field);
2876 /* FIELD is a non bit-field. We are finishing the processing for its
2877 enclosing type T. Issue any appropriate messages and set appropriate
2881 check_field_decl (tree field,
2883 int* cant_have_const_ctor,
2884 int* no_const_asn_ref,
2885 int* any_default_members)
2887 tree type = strip_array_types (TREE_TYPE (field));
2889 /* In C++98 an anonymous union cannot contain any fields which would change
2890 the settings of CANT_HAVE_CONST_CTOR and friends. */
2891 if (ANON_UNION_TYPE_P (type) && cxx_dialect < cxx0x)
2893 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
2894 structs. So, we recurse through their fields here. */
2895 else if (ANON_AGGR_TYPE_P (type))
2899 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2900 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2901 check_field_decl (fields, t, cant_have_const_ctor,
2902 no_const_asn_ref, any_default_members);
2904 /* Check members with class type for constructors, destructors,
2906 else if (CLASS_TYPE_P (type))
2908 /* Never let anything with uninheritable virtuals
2909 make it through without complaint. */
2910 abstract_virtuals_error (field, type);
2912 if (TREE_CODE (t) == UNION_TYPE && cxx_dialect < cxx0x)
2915 int oldcount = errorcount;
2916 if (TYPE_NEEDS_CONSTRUCTING (type))
2917 error ("member %q+#D with constructor not allowed in union",
2919 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2920 error ("member %q+#D with destructor not allowed in union", field);
2921 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
2922 error ("member %q+#D with copy assignment operator not allowed in union",
2924 if (!warned && errorcount > oldcount)
2926 inform (DECL_SOURCE_LOCATION (field), "unrestricted unions "
2927 "only available with -std=c++0x or -std=gnu++0x");
2933 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2934 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2935 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2936 TYPE_HAS_COMPLEX_COPY_ASSIGN (t)
2937 |= (TYPE_HAS_COMPLEX_COPY_ASSIGN (type)
2938 || !TYPE_HAS_COPY_ASSIGN (type));
2939 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= (TYPE_HAS_COMPLEX_COPY_CTOR (type)
2940 || !TYPE_HAS_COPY_CTOR (type));
2941 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_HAS_COMPLEX_MOVE_ASSIGN (type);
2942 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_HAS_COMPLEX_MOVE_CTOR (type);
2943 TYPE_HAS_COMPLEX_DFLT (t) |= (!TYPE_HAS_DEFAULT_CONSTRUCTOR (type)
2944 || TYPE_HAS_COMPLEX_DFLT (type));
2947 if (TYPE_HAS_COPY_CTOR (type)
2948 && !TYPE_HAS_CONST_COPY_CTOR (type))
2949 *cant_have_const_ctor = 1;
2951 if (TYPE_HAS_COPY_ASSIGN (type)
2952 && !TYPE_HAS_CONST_COPY_ASSIGN (type))
2953 *no_const_asn_ref = 1;
2955 if (DECL_INITIAL (field) != NULL_TREE)
2957 /* `build_class_init_list' does not recognize
2959 if (TREE_CODE (t) == UNION_TYPE && *any_default_members != 0)
2960 error ("multiple fields in union %qT initialized", t);
2961 *any_default_members = 1;
2965 /* Check the data members (both static and non-static), class-scoped
2966 typedefs, etc., appearing in the declaration of T. Issue
2967 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2968 declaration order) of access declarations; each TREE_VALUE in this
2969 list is a USING_DECL.
2971 In addition, set the following flags:
2974 The class is empty, i.e., contains no non-static data members.
2976 CANT_HAVE_CONST_CTOR_P
2977 This class cannot have an implicitly generated copy constructor
2978 taking a const reference.
2980 CANT_HAVE_CONST_ASN_REF
2981 This class cannot have an implicitly generated assignment
2982 operator taking a const reference.
2984 All of these flags should be initialized before calling this
2987 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2988 fields can be added by adding to this chain. */
2991 check_field_decls (tree t, tree *access_decls,
2992 int *cant_have_const_ctor_p,
2993 int *no_const_asn_ref_p)
2998 int any_default_members;
3000 int field_access = -1;
3002 /* Assume there are no access declarations. */
3003 *access_decls = NULL_TREE;
3004 /* Assume this class has no pointer members. */
3005 has_pointers = false;
3006 /* Assume none of the members of this class have default
3008 any_default_members = 0;
3010 for (field = &TYPE_FIELDS (t); *field; field = next)
3013 tree type = TREE_TYPE (x);
3014 int this_field_access;
3016 next = &DECL_CHAIN (x);
3018 if (TREE_CODE (x) == USING_DECL)
3020 /* Prune the access declaration from the list of fields. */
3021 *field = DECL_CHAIN (x);
3023 /* Save the access declarations for our caller. */
3024 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
3026 /* Since we've reset *FIELD there's no reason to skip to the
3032 if (TREE_CODE (x) == TYPE_DECL
3033 || TREE_CODE (x) == TEMPLATE_DECL)
3036 /* If we've gotten this far, it's a data member, possibly static,
3037 or an enumerator. */
3038 DECL_CONTEXT (x) = t;
3040 /* When this goes into scope, it will be a non-local reference. */
3041 DECL_NONLOCAL (x) = 1;
3043 if (TREE_CODE (t) == UNION_TYPE)
3047 If a union contains a static data member, or a member of
3048 reference type, the program is ill-formed. */
3049 if (TREE_CODE (x) == VAR_DECL)
3051 error ("%q+D may not be static because it is a member of a union", x);
3054 if (TREE_CODE (type) == REFERENCE_TYPE)
3056 error ("%q+D may not have reference type %qT because"
3057 " it is a member of a union",
3063 /* Perform error checking that did not get done in
3065 if (TREE_CODE (type) == FUNCTION_TYPE)
3067 error ("field %q+D invalidly declared function type", x);
3068 type = build_pointer_type (type);
3069 TREE_TYPE (x) = type;
3071 else if (TREE_CODE (type) == METHOD_TYPE)
3073 error ("field %q+D invalidly declared method type", x);
3074 type = build_pointer_type (type);
3075 TREE_TYPE (x) = type;
3078 if (type == error_mark_node)
3081 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
3084 /* Now it can only be a FIELD_DECL. */
3086 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
3087 CLASSTYPE_NON_AGGREGATE (t) = 1;
3089 /* If at least one non-static data member is non-literal, the whole
3090 class becomes non-literal. */
3091 if (!literal_type_p (type))
3092 CLASSTYPE_LITERAL_P (t) = false;
3094 /* A standard-layout class is a class that:
3096 has the same access control (Clause 11) for all non-static data members,
3098 this_field_access = TREE_PROTECTED (x) ? 1 : TREE_PRIVATE (x) ? 2 : 0;
3099 if (field_access == -1)
3100 field_access = this_field_access;
3101 else if (this_field_access != field_access)
3102 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3104 /* If this is of reference type, check if it needs an init. */
3105 if (TREE_CODE (type) == REFERENCE_TYPE)
3107 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3108 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3109 if (DECL_INITIAL (x) == NULL_TREE)
3110 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3112 /* ARM $12.6.2: [A member initializer list] (or, for an
3113 aggregate, initialization by a brace-enclosed list) is the
3114 only way to initialize nonstatic const and reference
3116 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3117 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3120 type = strip_array_types (type);
3122 if (TYPE_PACKED (t))
3124 if (!layout_pod_type_p (type) && !TYPE_PACKED (type))
3128 "ignoring packed attribute because of unpacked non-POD field %q+#D",
3132 else if (DECL_C_BIT_FIELD (x)
3133 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
3134 DECL_PACKED (x) = 1;
3137 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
3138 /* We don't treat zero-width bitfields as making a class
3143 /* The class is non-empty. */
3144 CLASSTYPE_EMPTY_P (t) = 0;
3145 /* The class is not even nearly empty. */
3146 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3147 /* If one of the data members contains an empty class,
3149 if (CLASS_TYPE_P (type)
3150 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3151 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
3154 /* This is used by -Weffc++ (see below). Warn only for pointers
3155 to members which might hold dynamic memory. So do not warn
3156 for pointers to functions or pointers to members. */
3157 if (TYPE_PTR_P (type)
3158 && !TYPE_PTRFN_P (type)
3159 && !TYPE_PTR_TO_MEMBER_P (type))
3160 has_pointers = true;
3162 if (CLASS_TYPE_P (type))
3164 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3165 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3166 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3167 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3170 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3171 CLASSTYPE_HAS_MUTABLE (t) = 1;
3173 if (! layout_pod_type_p (type))
3174 /* DR 148 now allows pointers to members (which are POD themselves),
3175 to be allowed in POD structs. */
3176 CLASSTYPE_NON_LAYOUT_POD_P (t) = 1;
3178 if (!std_layout_type_p (type))
3179 CLASSTYPE_NON_STD_LAYOUT (t) = 1;
3181 if (! zero_init_p (type))
3182 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3184 /* We set DECL_C_BIT_FIELD in grokbitfield.
3185 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3186 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3187 check_field_decl (x, t,
3188 cant_have_const_ctor_p,
3190 &any_default_members);
3192 /* If any field is const, the structure type is pseudo-const. */
3193 if (CP_TYPE_CONST_P (type))
3195 C_TYPE_FIELDS_READONLY (t) = 1;
3196 if (DECL_INITIAL (x) == NULL_TREE)
3197 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3199 /* ARM $12.6.2: [A member initializer list] (or, for an
3200 aggregate, initialization by a brace-enclosed list) is the
3201 only way to initialize nonstatic const and reference
3203 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
3204 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) = 1;
3206 /* A field that is pseudo-const makes the structure likewise. */
3207 else if (CLASS_TYPE_P (type))
3209 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3210 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3211 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3212 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3215 /* Core issue 80: A nonstatic data member is required to have a
3216 different name from the class iff the class has a
3217 user-declared constructor. */
3218 if (constructor_name_p (DECL_NAME (x), t)
3219 && TYPE_HAS_USER_CONSTRUCTOR (t))
3220 permerror (input_location, "field %q+#D with same name as class", x);
3223 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3224 it should also define a copy constructor and an assignment operator to
3225 implement the correct copy semantic (deep vs shallow, etc.). As it is
3226 not feasible to check whether the constructors do allocate dynamic memory
3227 and store it within members, we approximate the warning like this:
3229 -- Warn only if there are members which are pointers
3230 -- Warn only if there is a non-trivial constructor (otherwise,
3231 there cannot be memory allocated).
3232 -- Warn only if there is a non-trivial destructor. We assume that the
3233 user at least implemented the cleanup correctly, and a destructor
3234 is needed to free dynamic memory.
3236 This seems enough for practical purposes. */
3239 && TYPE_HAS_USER_CONSTRUCTOR (t)
3240 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3241 && !(TYPE_HAS_COPY_CTOR (t) && TYPE_HAS_COPY_ASSIGN (t)))
3243 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3245 if (! TYPE_HAS_COPY_CTOR (t))
3247 warning (OPT_Weffc__,
3248 " but does not override %<%T(const %T&)%>", t, t);
3249 if (!TYPE_HAS_COPY_ASSIGN (t))
3250 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3252 else if (! TYPE_HAS_COPY_ASSIGN (t))
3253 warning (OPT_Weffc__,
3254 " but does not override %<operator=(const %T&)%>", t);
3257 /* Non-static data member initializers make the default constructor
3259 if (any_default_members)
3261 TYPE_NEEDS_CONSTRUCTING (t) = true;
3262 TYPE_HAS_COMPLEX_DFLT (t) = true;
3265 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3267 TYPE_PACKED (t) = 0;
3269 /* Check anonymous struct/anonymous union fields. */
3270 finish_struct_anon (t);
3272 /* We've built up the list of access declarations in reverse order.
3274 *access_decls = nreverse (*access_decls);
3277 /* If TYPE is an empty class type, records its OFFSET in the table of
3281 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3285 if (!is_empty_class (type))
3288 /* Record the location of this empty object in OFFSETS. */
3289 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3291 n = splay_tree_insert (offsets,
3292 (splay_tree_key) offset,
3293 (splay_tree_value) NULL_TREE);
3294 n->value = ((splay_tree_value)
3295 tree_cons (NULL_TREE,
3302 /* Returns nonzero if TYPE is an empty class type and there is
3303 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3306 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3311 if (!is_empty_class (type))
3314 /* Record the location of this empty object in OFFSETS. */
3315 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3319 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3320 if (same_type_p (TREE_VALUE (t), type))
3326 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3327 F for every subobject, passing it the type, offset, and table of
3328 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3331 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3332 than MAX_OFFSET will not be walked.
3334 If F returns a nonzero value, the traversal ceases, and that value
3335 is returned. Otherwise, returns zero. */
3338 walk_subobject_offsets (tree type,
3339 subobject_offset_fn f,
3346 tree type_binfo = NULL_TREE;
3348 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3350 if (max_offset && INT_CST_LT (max_offset, offset))
3353 if (type == error_mark_node)
3358 if (abi_version_at_least (2))
3360 type = BINFO_TYPE (type);
3363 if (CLASS_TYPE_P (type))
3369 /* Avoid recursing into objects that are not interesting. */
3370 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3373 /* Record the location of TYPE. */
3374 r = (*f) (type, offset, offsets);
3378 /* Iterate through the direct base classes of TYPE. */
3380 type_binfo = TYPE_BINFO (type);
3381 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3385 if (abi_version_at_least (2)
3386 && BINFO_VIRTUAL_P (binfo))
3390 && BINFO_VIRTUAL_P (binfo)
3391 && !BINFO_PRIMARY_P (binfo))
3394 if (!abi_version_at_least (2))
3395 binfo_offset = size_binop (PLUS_EXPR,
3397 BINFO_OFFSET (binfo));
3401 /* We cannot rely on BINFO_OFFSET being set for the base
3402 class yet, but the offsets for direct non-virtual
3403 bases can be calculated by going back to the TYPE. */
3404 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3405 binfo_offset = size_binop (PLUS_EXPR,
3407 BINFO_OFFSET (orig_binfo));
3410 r = walk_subobject_offsets (binfo,
3415 (abi_version_at_least (2)
3416 ? /*vbases_p=*/0 : vbases_p));
3421 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3424 VEC(tree,gc) *vbases;
3426 /* Iterate through the virtual base classes of TYPE. In G++
3427 3.2, we included virtual bases in the direct base class
3428 loop above, which results in incorrect results; the
3429 correct offsets for virtual bases are only known when
3430 working with the most derived type. */
3432 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3433 VEC_iterate (tree, vbases, ix, binfo); ix++)
3435 r = walk_subobject_offsets (binfo,
3437 size_binop (PLUS_EXPR,
3439 BINFO_OFFSET (binfo)),
3448 /* We still have to walk the primary base, if it is
3449 virtual. (If it is non-virtual, then it was walked
3451 tree vbase = get_primary_binfo (type_binfo);
3453 if (vbase && BINFO_VIRTUAL_P (vbase)
3454 && BINFO_PRIMARY_P (vbase)
3455 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3457 r = (walk_subobject_offsets
3459 offsets, max_offset, /*vbases_p=*/0));
3466 /* Iterate through the fields of TYPE. */
3467 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
3468 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3472 if (abi_version_at_least (2))
3473 field_offset = byte_position (field);
3475 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3476 field_offset = DECL_FIELD_OFFSET (field);
3478 r = walk_subobject_offsets (TREE_TYPE (field),
3480 size_binop (PLUS_EXPR,
3490 else if (TREE_CODE (type) == ARRAY_TYPE)
3492 tree element_type = strip_array_types (type);
3493 tree domain = TYPE_DOMAIN (type);
3496 /* Avoid recursing into objects that are not interesting. */
3497 if (!CLASS_TYPE_P (element_type)
3498 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3501 /* Step through each of the elements in the array. */
3502 for (index = size_zero_node;
3503 /* G++ 3.2 had an off-by-one error here. */
3504 (abi_version_at_least (2)
3505 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3506 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3507 index = size_binop (PLUS_EXPR, index, size_one_node))
3509 r = walk_subobject_offsets (TREE_TYPE (type),
3517 offset = size_binop (PLUS_EXPR, offset,
3518 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3519 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3520 there's no point in iterating through the remaining
3521 elements of the array. */
3522 if (max_offset && INT_CST_LT (max_offset, offset))
3530 /* Record all of the empty subobjects of TYPE (either a type or a
3531 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3532 is being placed at OFFSET; otherwise, it is a base class that is
3533 being placed at OFFSET. */
3536 record_subobject_offsets (tree type,
3539 bool is_data_member)
3542 /* If recording subobjects for a non-static data member or a
3543 non-empty base class , we do not need to record offsets beyond
3544 the size of the biggest empty class. Additional data members
3545 will go at the end of the class. Additional base classes will go
3546 either at offset zero (if empty, in which case they cannot
3547 overlap with offsets past the size of the biggest empty class) or
3548 at the end of the class.
3550 However, if we are placing an empty base class, then we must record
3551 all offsets, as either the empty class is at offset zero (where
3552 other empty classes might later be placed) or at the end of the
3553 class (where other objects might then be placed, so other empty
3554 subobjects might later overlap). */
3556 || !is_empty_class (BINFO_TYPE (type)))
3557 max_offset = sizeof_biggest_empty_class;
3559 max_offset = NULL_TREE;
3560 walk_subobject_offsets (type, record_subobject_offset, offset,
3561 offsets, max_offset, is_data_member);
3564 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3565 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3566 virtual bases of TYPE are examined. */
3569 layout_conflict_p (tree type,
3574 splay_tree_node max_node;
3576 /* Get the node in OFFSETS that indicates the maximum offset where
3577 an empty subobject is located. */
3578 max_node = splay_tree_max (offsets);
3579 /* If there aren't any empty subobjects, then there's no point in
3580 performing this check. */
3584 return walk_subobject_offsets (type, check_subobject_offset, offset,
3585 offsets, (tree) (max_node->key),
3589 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3590 non-static data member of the type indicated by RLI. BINFO is the
3591 binfo corresponding to the base subobject, OFFSETS maps offsets to
3592 types already located at those offsets. This function determines
3593 the position of the DECL. */
3596 layout_nonempty_base_or_field (record_layout_info rli,
3601 tree offset = NULL_TREE;
3607 /* For the purposes of determining layout conflicts, we want to
3608 use the class type of BINFO; TREE_TYPE (DECL) will be the
3609 CLASSTYPE_AS_BASE version, which does not contain entries for
3610 zero-sized bases. */
3611 type = TREE_TYPE (binfo);
3616 type = TREE_TYPE (decl);
3620 /* Try to place the field. It may take more than one try if we have
3621 a hard time placing the field without putting two objects of the
3622 same type at the same address. */
3625 struct record_layout_info_s old_rli = *rli;
3627 /* Place this field. */
3628 place_field (rli, decl);
3629 offset = byte_position (decl);
3631 /* We have to check to see whether or not there is already
3632 something of the same type at the offset we're about to use.
3633 For example, consider:
3636 struct T : public S { int i; };
3637 struct U : public S, public T {};
3639 Here, we put S at offset zero in U. Then, we can't put T at
3640 offset zero -- its S component would be at the same address
3641 as the S we already allocated. So, we have to skip ahead.
3642 Since all data members, including those whose type is an
3643 empty class, have nonzero size, any overlap can happen only
3644 with a direct or indirect base-class -- it can't happen with
3646 /* In a union, overlap is permitted; all members are placed at
3648 if (TREE_CODE (rli->t) == UNION_TYPE)
3650 /* G++ 3.2 did not check for overlaps when placing a non-empty
3652 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3654 if (layout_conflict_p (field_p ? type : binfo, offset,
3657 /* Strip off the size allocated to this field. That puts us
3658 at the first place we could have put the field with
3659 proper alignment. */
3662 /* Bump up by the alignment required for the type. */
3664 = size_binop (PLUS_EXPR, rli->bitpos,
3666 ? CLASSTYPE_ALIGN (type)
3667 : TYPE_ALIGN (type)));
3668 normalize_rli (rli);
3671 /* There was no conflict. We're done laying out this field. */
3675 /* Now that we know where it will be placed, update its
3677 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3678 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3679 this point because their BINFO_OFFSET is copied from another
3680 hierarchy. Therefore, we may not need to add the entire
3682 propagate_binfo_offsets (binfo,
3683 size_diffop_loc (input_location,
3684 convert (ssizetype, offset),
3686 BINFO_OFFSET (binfo))));
3689 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3692 empty_base_at_nonzero_offset_p (tree type,
3694 splay_tree offsets ATTRIBUTE_UNUSED)
3696 return is_empty_class (type) && !integer_zerop (offset);
3699 /* Layout the empty base BINFO. EOC indicates the byte currently just
3700 past the end of the class, and should be correctly aligned for a
3701 class of the type indicated by BINFO; OFFSETS gives the offsets of
3702 the empty bases allocated so far. T is the most derived
3703 type. Return nonzero iff we added it at the end. */
3706 layout_empty_base (record_layout_info rli, tree binfo,
3707 tree eoc, splay_tree offsets)
3710 tree basetype = BINFO_TYPE (binfo);
3713 /* This routine should only be used for empty classes. */
3714 gcc_assert (is_empty_class (basetype));
3715 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3717 if (!integer_zerop (BINFO_OFFSET (binfo)))
3719 if (abi_version_at_least (2))
3720 propagate_binfo_offsets
3721 (binfo, size_diffop_loc (input_location,
3722 size_zero_node, BINFO_OFFSET (binfo)));
3725 "offset of empty base %qT may not be ABI-compliant and may"
3726 "change in a future version of GCC",
3727 BINFO_TYPE (binfo));
3730 /* This is an empty base class. We first try to put it at offset
3732 if (layout_conflict_p (binfo,
3733 BINFO_OFFSET (binfo),
3737 /* That didn't work. Now, we move forward from the next
3738 available spot in the class. */
3740 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3743 if (!layout_conflict_p (binfo,
3744 BINFO_OFFSET (binfo),
3747 /* We finally found a spot where there's no overlap. */
3750 /* There's overlap here, too. Bump along to the next spot. */
3751 propagate_binfo_offsets (binfo, alignment);
3755 if (CLASSTYPE_USER_ALIGN (basetype))
3757 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3759 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3760 TYPE_USER_ALIGN (rli->t) = 1;
3766 /* Layout the base given by BINFO in the class indicated by RLI.
3767 *BASE_ALIGN is a running maximum of the alignments of
3768 any base class. OFFSETS gives the location of empty base
3769 subobjects. T is the most derived type. Return nonzero if the new
3770 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3771 *NEXT_FIELD, unless BINFO is for an empty base class.
3773 Returns the location at which the next field should be inserted. */
3776 build_base_field (record_layout_info rli, tree binfo,
3777 splay_tree offsets, tree *next_field)
3780 tree basetype = BINFO_TYPE (binfo);
3782 if (!COMPLETE_TYPE_P (basetype))
3783 /* This error is now reported in xref_tag, thus giving better
3784 location information. */
3787 /* Place the base class. */
3788 if (!is_empty_class (basetype))
3792 /* The containing class is non-empty because it has a non-empty
3794 CLASSTYPE_EMPTY_P (t) = 0;
3796 /* Create the FIELD_DECL. */
3797 decl = build_decl (input_location,
3798 FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3799 DECL_ARTIFICIAL (decl) = 1;
3800 DECL_IGNORED_P (decl) = 1;
3801 DECL_FIELD_CONTEXT (decl) = t;
3802 if (CLASSTYPE_AS_BASE (basetype))
3804 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3805 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3806 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3807 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3808 DECL_MODE (decl) = TYPE_MODE (basetype);
3809 DECL_FIELD_IS_BASE (decl) = 1;
3811 /* Try to place the field. It may take more than one try if we
3812 have a hard time placing the field without putting two
3813 objects of the same type at the same address. */
3814 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3815 /* Add the new FIELD_DECL to the list of fields for T. */
3816 DECL_CHAIN (decl) = *next_field;
3818 next_field = &DECL_CHAIN (decl);
3826 /* On some platforms (ARM), even empty classes will not be
3828 eoc = round_up_loc (input_location,
3829 rli_size_unit_so_far (rli),
3830 CLASSTYPE_ALIGN_UNIT (basetype));
3831 atend = layout_empty_base (rli, binfo, eoc, offsets);
3832 /* A nearly-empty class "has no proper base class that is empty,
3833 not morally virtual, and at an offset other than zero." */
3834 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3837 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3838 /* The check above (used in G++ 3.2) is insufficient because
3839 an empty class placed at offset zero might itself have an
3840 empty base at a nonzero offset. */
3841 else if (walk_subobject_offsets (basetype,
3842 empty_base_at_nonzero_offset_p,
3845 /*max_offset=*/NULL_TREE,
3848 if (abi_version_at_least (2))
3849 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3852 "class %qT will be considered nearly empty in a "
3853 "future version of GCC", t);
3857 /* We do not create a FIELD_DECL for empty base classes because
3858 it might overlap some other field. We want to be able to
3859 create CONSTRUCTORs for the class by iterating over the
3860 FIELD_DECLs, and the back end does not handle overlapping
3863 /* An empty virtual base causes a class to be non-empty
3864 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3865 here because that was already done when the virtual table
3866 pointer was created. */
3869 /* Record the offsets of BINFO and its base subobjects. */
3870 record_subobject_offsets (binfo,
3871 BINFO_OFFSET (binfo),
3873 /*is_data_member=*/false);
3878 /* Layout all of the non-virtual base classes. Record empty
3879 subobjects in OFFSETS. T is the most derived type. Return nonzero
3880 if the type cannot be nearly empty. The fields created
3881 corresponding to the base classes will be inserted at
3885 build_base_fields (record_layout_info rli,
3886 splay_tree offsets, tree *next_field)
3888 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3891 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3894 /* The primary base class is always allocated first. */
3895 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3896 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3897 offsets, next_field);
3899 /* Now allocate the rest of the bases. */
3900 for (i = 0; i < n_baseclasses; ++i)
3904 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3906 /* The primary base was already allocated above, so we don't
3907 need to allocate it again here. */
3908 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3911 /* Virtual bases are added at the end (a primary virtual base
3912 will have already been added). */
3913 if (BINFO_VIRTUAL_P (base_binfo))
3916 next_field = build_base_field (rli, base_binfo,
3917 offsets, next_field);
3921 /* Go through the TYPE_METHODS of T issuing any appropriate
3922 diagnostics, figuring out which methods override which other
3923 methods, and so forth. */
3926 check_methods (tree t)
3930 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
3932 check_for_override (x, t);
3933 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3934 error ("initializer specified for non-virtual method %q+D", x);
3935 /* The name of the field is the original field name
3936 Save this in auxiliary field for later overloading. */
3937 if (DECL_VINDEX (x))
3939 TYPE_POLYMORPHIC_P (t) = 1;
3940 if (DECL_PURE_VIRTUAL_P (x))
3941 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3943 /* All user-provided destructors are non-trivial.
3944 Constructors and assignment ops are handled in
3945 grok_special_member_properties. */
3946 if (DECL_DESTRUCTOR_P (x) && user_provided_p (x))
3947 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3951 /* FN is a constructor or destructor. Clone the declaration to create
3952 a specialized in-charge or not-in-charge version, as indicated by
3956 build_clone (tree fn, tree name)
3961 /* Copy the function. */
3962 clone = copy_decl (fn);
3963 /* Reset the function name. */
3964 DECL_NAME (clone) = name;
3965 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3966 /* Remember where this function came from. */
3967 DECL_ABSTRACT_ORIGIN (clone) = fn;
3968 /* Make it easy to find the CLONE given the FN. */
3969 DECL_CHAIN (clone) = DECL_CHAIN (fn);
3970 DECL_CHAIN (fn) = clone;
3972 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3973 if (TREE_CODE (clone) == TEMPLATE_DECL)
3975 tree result = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3976 DECL_TEMPLATE_RESULT (clone) = result;
3977 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3978 DECL_TI_TEMPLATE (result) = clone;
3979 TREE_TYPE (clone) = TREE_TYPE (result);
3983 DECL_CLONED_FUNCTION (clone) = fn;
3984 /* There's no pending inline data for this function. */
3985 DECL_PENDING_INLINE_INFO (clone) = NULL;
3986 DECL_PENDING_INLINE_P (clone) = 0;
3988 /* The base-class destructor is not virtual. */
3989 if (name == base_dtor_identifier)
3991 DECL_VIRTUAL_P (clone) = 0;
3992 if (TREE_CODE (clone) != TEMPLATE_DECL)
3993 DECL_VINDEX (clone) = NULL_TREE;
3996 /* If there was an in-charge parameter, drop it from the function
3998 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4004 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4005 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4006 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
4007 /* Skip the `this' parameter. */
4008 parmtypes = TREE_CHAIN (parmtypes);
4009 /* Skip the in-charge parameter. */
4010 parmtypes = TREE_CHAIN (parmtypes);
4011 /* And the VTT parm, in a complete [cd]tor. */
4012 if (DECL_HAS_VTT_PARM_P (fn)
4013 && ! DECL_NEEDS_VTT_PARM_P (clone))
4014 parmtypes = TREE_CHAIN (parmtypes);
4015 /* If this is subobject constructor or destructor, add the vtt
4018 = build_method_type_directly (basetype,
4019 TREE_TYPE (TREE_TYPE (clone)),
4022 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
4025 = cp_build_type_attribute_variant (TREE_TYPE (clone),
4026 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
4029 /* Copy the function parameters. */
4030 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
4031 /* Remove the in-charge parameter. */
4032 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
4034 DECL_CHAIN (DECL_ARGUMENTS (clone))
4035 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4036 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
4038 /* And the VTT parm, in a complete [cd]tor. */
4039 if (DECL_HAS_VTT_PARM_P (fn))
4041 if (DECL_NEEDS_VTT_PARM_P (clone))
4042 DECL_HAS_VTT_PARM_P (clone) = 1;
4045 DECL_CHAIN (DECL_ARGUMENTS (clone))
4046 = DECL_CHAIN (DECL_CHAIN (DECL_ARGUMENTS (clone)));
4047 DECL_HAS_VTT_PARM_P (clone) = 0;
4051 for (parms = DECL_ARGUMENTS (clone); parms; parms = DECL_CHAIN (parms))
4053 DECL_CONTEXT (parms) = clone;
4054 cxx_dup_lang_specific_decl (parms);
4057 /* Create the RTL for this function. */
4058 SET_DECL_RTL (clone, NULL);
4059 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
4062 note_decl_for_pch (clone);
4067 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4068 not invoke this function directly.
4070 For a non-thunk function, returns the address of the slot for storing
4071 the function it is a clone of. Otherwise returns NULL_TREE.
4073 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4074 cloned_function is unset. This is to support the separate
4075 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4076 on a template makes sense, but not the former. */
4079 decl_cloned_function_p (const_tree decl, bool just_testing)
4083 decl = STRIP_TEMPLATE (decl);
4085 if (TREE_CODE (decl) != FUNCTION_DECL
4086 || !DECL_LANG_SPECIFIC (decl)
4087 || DECL_LANG_SPECIFIC (decl)->u.fn.thunk_p)
4089 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4091 lang_check_failed (__FILE__, __LINE__, __FUNCTION__);
4097 ptr = &DECL_LANG_SPECIFIC (decl)->u.fn.u5.cloned_function;
4098 if (just_testing && *ptr == NULL_TREE)
4104 /* Produce declarations for all appropriate clones of FN. If
4105 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4106 CLASTYPE_METHOD_VEC as well. */
4109 clone_function_decl (tree fn, int update_method_vec_p)
4113 /* Avoid inappropriate cloning. */
4115 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (fn)))
4118 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
4120 /* For each constructor, we need two variants: an in-charge version
4121 and a not-in-charge version. */
4122 clone = build_clone (fn, complete_ctor_identifier);
4123 if (update_method_vec_p)
4124 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4125 clone = build_clone (fn, base_ctor_identifier);
4126 if (update_method_vec_p)
4127 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4131 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
4133 /* For each destructor, we need three variants: an in-charge
4134 version, a not-in-charge version, and an in-charge deleting
4135 version. We clone the deleting version first because that
4136 means it will go second on the TYPE_METHODS list -- and that
4137 corresponds to the correct layout order in the virtual
4140 For a non-virtual destructor, we do not build a deleting
4142 if (DECL_VIRTUAL_P (fn))
4144 clone = build_clone (fn, deleting_dtor_identifier);
4145 if (update_method_vec_p)
4146 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4148 clone = build_clone (fn, complete_dtor_identifier);
4149 if (update_method_vec_p)
4150 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4151 clone = build_clone (fn, base_dtor_identifier);
4152 if (update_method_vec_p)
4153 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
4156 /* Note that this is an abstract function that is never emitted. */
4157 DECL_ABSTRACT (fn) = 1;
4160 /* DECL is an in charge constructor, which is being defined. This will
4161 have had an in class declaration, from whence clones were
4162 declared. An out-of-class definition can specify additional default
4163 arguments. As it is the clones that are involved in overload
4164 resolution, we must propagate the information from the DECL to its
4168 adjust_clone_args (tree decl)
4172 for (clone = DECL_CHAIN (decl); clone && DECL_CLONED_FUNCTION_P (clone);
4173 clone = DECL_CHAIN (clone))
4175 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
4176 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
4177 tree decl_parms, clone_parms;
4179 clone_parms = orig_clone_parms;
4181 /* Skip the 'this' parameter. */
4182 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
4183 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4185 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
4186 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4187 if (DECL_HAS_VTT_PARM_P (decl))
4188 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
4190 clone_parms = orig_clone_parms;
4191 if (DECL_HAS_VTT_PARM_P (clone))
4192 clone_parms = TREE_CHAIN (clone_parms);
4194 for (decl_parms = orig_decl_parms; decl_parms;
4195 decl_parms = TREE_CHAIN (decl_parms),
4196 clone_parms = TREE_CHAIN (clone_parms))
4198 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
4199 TREE_TYPE (clone_parms)));
4201 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
4203 /* A default parameter has been added. Adjust the
4204 clone's parameters. */
4205 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4206 tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (clone));
4207 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4210 clone_parms = orig_decl_parms;
4212 if (DECL_HAS_VTT_PARM_P (clone))
4214 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4215 TREE_VALUE (orig_clone_parms),
4217 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4219 type = build_method_type_directly (basetype,
4220 TREE_TYPE (TREE_TYPE (clone)),
4223 type = build_exception_variant (type, exceptions);
4225 type = cp_build_type_attribute_variant (type, attrs);
4226 TREE_TYPE (clone) = type;
4228 clone_parms = NULL_TREE;
4232 gcc_assert (!clone_parms);
4236 /* For each of the constructors and destructors in T, create an
4237 in-charge and not-in-charge variant. */
4240 clone_constructors_and_destructors (tree t)
4244 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4246 if (!CLASSTYPE_METHOD_VEC (t))
4249 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4250 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4251 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4252 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4255 /* Returns true iff class T has a user-defined constructor other than
4256 the default constructor. */
4259 type_has_user_nondefault_constructor (tree t)
4263 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4266 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4268 tree fn = OVL_CURRENT (fns);
4269 if (!DECL_ARTIFICIAL (fn)
4270 && (TREE_CODE (fn) == TEMPLATE_DECL
4271 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4279 /* Returns the defaulted constructor if T has one. Otherwise, returns
4283 in_class_defaulted_default_constructor (tree t)
4287 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4290 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4292 tree fn = OVL_CURRENT (fns);
4294 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4296 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4297 while (args && TREE_PURPOSE (args))
4298 args = TREE_CHAIN (args);
4299 if (!args || args == void_list_node)
4307 /* Returns true iff FN is a user-provided function, i.e. user-declared
4308 and not defaulted at its first declaration; or explicit, private,
4309 protected, or non-const. */
4312 user_provided_p (tree fn)
4314 if (TREE_CODE (fn) == TEMPLATE_DECL)
4317 return (!DECL_ARTIFICIAL (fn)
4318 && !DECL_DEFAULTED_IN_CLASS_P (fn));
4321 /* Returns true iff class T has a user-provided constructor. */
4324 type_has_user_provided_constructor (tree t)
4328 if (!CLASS_TYPE_P (t))
4331 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4334 /* This can happen in error cases; avoid crashing. */
4335 if (!CLASSTYPE_METHOD_VEC (t))
4338 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4339 if (user_provided_p (OVL_CURRENT (fns)))
4345 /* Returns true iff class T has a user-provided default constructor. */
4348 type_has_user_provided_default_constructor (tree t)
4352 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4355 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4357 tree fn = OVL_CURRENT (fns);
4358 if (TREE_CODE (fn) == FUNCTION_DECL
4359 && user_provided_p (fn)
4360 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)))
4367 /* If default-initialization leaves part of TYPE uninitialized, returns
4368 a DECL for the field or TYPE itself (DR 253). */
4371 default_init_uninitialized_part (tree type)
4376 type = strip_array_types (type);
4377 if (!CLASS_TYPE_P (type))
4379 if (type_has_user_provided_default_constructor (type))
4381 for (binfo = TYPE_BINFO (type), i = 0;
4382 BINFO_BASE_ITERATE (binfo, i, t); ++i)
4384 r = default_init_uninitialized_part (BINFO_TYPE (t));
4388 for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t))
4389 if (TREE_CODE (t) == FIELD_DECL
4390 && !DECL_ARTIFICIAL (t)
4391 && !DECL_INITIAL (t))
4393 r = default_init_uninitialized_part (TREE_TYPE (t));
4395 return DECL_P (r) ? r : t;
4401 /* Returns true iff for class T, a trivial synthesized default constructor
4402 would be constexpr. */
4405 trivial_default_constructor_is_constexpr (tree t)
4407 /* A defaulted trivial default constructor is constexpr
4408 if there is nothing to initialize. */
4409 gcc_assert (!TYPE_HAS_COMPLEX_DFLT (t));
4410 return is_really_empty_class (t);
4413 /* Returns true iff class T has a constexpr default constructor. */
4416 type_has_constexpr_default_constructor (tree t)
4420 if (!CLASS_TYPE_P (t))
4422 /* The caller should have stripped an enclosing array. */
4423 gcc_assert (TREE_CODE (t) != ARRAY_TYPE);
4426 if (CLASSTYPE_LAZY_DEFAULT_CTOR (t))
4428 if (!TYPE_HAS_COMPLEX_DFLT (t))
4429 return trivial_default_constructor_is_constexpr (t);
4430 /* Non-trivial, we need to check subobject constructors. */
4431 lazily_declare_fn (sfk_constructor, t);
4433 fns = locate_ctor (t);
4434 return (fns && DECL_DECLARED_CONSTEXPR_P (fns));
4437 /* Returns true iff class TYPE has a virtual destructor. */
4440 type_has_virtual_destructor (tree type)
4444 if (!CLASS_TYPE_P (type))
4447 gcc_assert (COMPLETE_TYPE_P (type));
4448 dtor = CLASSTYPE_DESTRUCTORS (type);
4449 return (dtor && DECL_VIRTUAL_P (dtor));
4452 /* Returns true iff class T has a move constructor. */
4455 type_has_move_constructor (tree t)
4459 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4461 gcc_assert (COMPLETE_TYPE_P (t));
4462 lazily_declare_fn (sfk_move_constructor, t);
4465 if (!CLASSTYPE_METHOD_VEC (t))
4468 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4469 if (move_fn_p (OVL_CURRENT (fns)))
4475 /* Returns true iff class T has a move assignment operator. */
4478 type_has_move_assign (tree t)
4482 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4484 gcc_assert (COMPLETE_TYPE_P (t));
4485 lazily_declare_fn (sfk_move_assignment, t);
4488 for (fns = lookup_fnfields_slot (t, ansi_assopname (NOP_EXPR));
4489 fns; fns = OVL_NEXT (fns))
4490 if (move_fn_p (OVL_CURRENT (fns)))
4496 /* Returns true iff class T has a move constructor that was explicitly
4497 declared in the class body. Note that this is different from
4498 "user-provided", which doesn't include functions that are defaulted in
4502 type_has_user_declared_move_constructor (tree t)
4506 if (CLASSTYPE_LAZY_MOVE_CTOR (t))
4509 if (!CLASSTYPE_METHOD_VEC (t))
4512 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4514 tree fn = OVL_CURRENT (fns);
4515 if (move_fn_p (fn) && !DECL_ARTIFICIAL (fn))
4522 /* Returns true iff class T has a move assignment operator that was
4523 explicitly declared in the class body. */
4526 type_has_user_declared_move_assign (tree t)
4530 if (CLASSTYPE_LAZY_MOVE_ASSIGN (t))
4533 for (fns = lookup_fnfields_slot (t, ansi_assopname (NOP_EXPR));
4534 fns; fns = OVL_NEXT (fns))
4536 tree fn = OVL_CURRENT (fns);
4537 if (move_fn_p (fn) && !DECL_ARTIFICIAL (fn))
4544 /* Nonzero if we need to build up a constructor call when initializing an
4545 object of this class, either because it has a user-provided constructor
4546 or because it doesn't have a default constructor (so we need to give an
4547 error if no initializer is provided). Use TYPE_NEEDS_CONSTRUCTING when
4548 what you care about is whether or not an object can be produced by a
4549 constructor (e.g. so we don't set TREE_READONLY on const variables of
4550 such type); use this function when what you care about is whether or not
4551 to try to call a constructor to create an object. The latter case is
4552 the former plus some cases of constructors that cannot be called. */
4555 type_build_ctor_call (tree t)
4558 if (TYPE_NEEDS_CONSTRUCTING (t))
4560 inner = strip_array_types (t);
4561 return (CLASS_TYPE_P (inner) && !TYPE_HAS_DEFAULT_CONSTRUCTOR (inner)
4562 && !ANON_AGGR_TYPE_P (inner));
4565 /* Remove all zero-width bit-fields from T. */
4568 remove_zero_width_bit_fields (tree t)
4572 fieldsp = &TYPE_FIELDS (t);
4575 if (TREE_CODE (*fieldsp) == FIELD_DECL
4576 && DECL_C_BIT_FIELD (*fieldsp)
4577 /* We should not be confused by the fact that grokbitfield
4578 temporarily sets the width of the bit field into
4579 DECL_INITIAL (*fieldsp).
4580 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4582 && integer_zerop (DECL_SIZE (*fieldsp)))
4583 *fieldsp = DECL_CHAIN (*fieldsp);
4585 fieldsp = &DECL_CHAIN (*fieldsp);
4589 /* Returns TRUE iff we need a cookie when dynamically allocating an
4590 array whose elements have the indicated class TYPE. */
4593 type_requires_array_cookie (tree type)
4596 bool has_two_argument_delete_p = false;
4598 gcc_assert (CLASS_TYPE_P (type));
4600 /* If there's a non-trivial destructor, we need a cookie. In order
4601 to iterate through the array calling the destructor for each
4602 element, we'll have to know how many elements there are. */
4603 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4606 /* If the usual deallocation function is a two-argument whose second
4607 argument is of type `size_t', then we have to pass the size of
4608 the array to the deallocation function, so we will need to store
4610 fns = lookup_fnfields (TYPE_BINFO (type),
4611 ansi_opname (VEC_DELETE_EXPR),
4613 /* If there are no `operator []' members, or the lookup is
4614 ambiguous, then we don't need a cookie. */
4615 if (!fns || fns == error_mark_node)
4617 /* Loop through all of the functions. */
4618 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4623 /* Select the current function. */
4624 fn = OVL_CURRENT (fns);
4625 /* See if this function is a one-argument delete function. If
4626 it is, then it will be the usual deallocation function. */
4627 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4628 if (second_parm == void_list_node)
4630 /* Do not consider this function if its second argument is an
4634 /* Otherwise, if we have a two-argument function and the second
4635 argument is `size_t', it will be the usual deallocation
4636 function -- unless there is one-argument function, too. */
4637 if (TREE_CHAIN (second_parm) == void_list_node
4638 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4639 has_two_argument_delete_p = true;
4642 return has_two_argument_delete_p;
4645 /* Finish computing the `literal type' property of class type T.
4647 At this point, we have already processed base classes and
4648 non-static data members. We need to check whether the copy
4649 constructor is trivial, the destructor is trivial, and there
4650 is a trivial default constructor or at least one constexpr
4651 constructor other than the copy constructor. */
4654 finalize_literal_type_property (tree t)
4658 if (cxx_dialect < cxx0x
4659 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
4660 CLASSTYPE_LITERAL_P (t) = false;
4661 else if (CLASSTYPE_LITERAL_P (t) && !TYPE_HAS_TRIVIAL_DFLT (t)
4662 && CLASSTYPE_NON_AGGREGATE (t)
4663 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4664 CLASSTYPE_LITERAL_P (t) = false;
4666 if (!CLASSTYPE_LITERAL_P (t))
4667 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4668 if (DECL_DECLARED_CONSTEXPR_P (fn)
4669 && TREE_CODE (fn) != TEMPLATE_DECL
4670 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
4671 && !DECL_CONSTRUCTOR_P (fn))
4673 DECL_DECLARED_CONSTEXPR_P (fn) = false;
4674 if (!DECL_GENERATED_P (fn))
4676 error ("enclosing class of constexpr non-static member "
4677 "function %q+#D is not a literal type", fn);
4678 explain_non_literal_class (t);
4683 /* T is a non-literal type used in a context which requires a constant
4684 expression. Explain why it isn't literal. */
4687 explain_non_literal_class (tree t)
4689 static struct pointer_set_t *diagnosed;
4691 if (!CLASS_TYPE_P (t))
4693 t = TYPE_MAIN_VARIANT (t);
4695 if (diagnosed == NULL)
4696 diagnosed = pointer_set_create ();
4697 if (pointer_set_insert (diagnosed, t) != 0)
4698 /* Already explained. */
4701 inform (0, "%q+T is not literal because:", t);
4702 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
4703 inform (0, " %q+T has a non-trivial destructor", t);
4704 else if (CLASSTYPE_NON_AGGREGATE (t)
4705 && !TYPE_HAS_TRIVIAL_DFLT (t)
4706 && !TYPE_HAS_CONSTEXPR_CTOR (t))
4708 inform (0, " %q+T is not an aggregate, does not have a trivial "
4709 "default constructor, and has no constexpr constructor that "
4710 "is not a copy or move constructor", t);
4711 if (TYPE_HAS_DEFAULT_CONSTRUCTOR (t)
4712 && !type_has_user_provided_default_constructor (t))
4713 explain_invalid_constexpr_fn (locate_ctor (t));
4717 tree binfo, base_binfo, field; int i;
4718 for (binfo = TYPE_BINFO (t), i = 0;
4719 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
4721 tree basetype = TREE_TYPE (base_binfo);
4722 if (!CLASSTYPE_LITERAL_P (basetype))
4724 inform (0, " base class %qT of %q+T is non-literal",
4726 explain_non_literal_class (basetype);
4730 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4733 if (TREE_CODE (field) != FIELD_DECL)
4735 ftype = TREE_TYPE (field);
4736 if (!literal_type_p (ftype))
4738 inform (0, " non-static data member %q+D has "
4739 "non-literal type", field);
4740 if (CLASS_TYPE_P (ftype))
4741 explain_non_literal_class (ftype);
4747 /* Check the validity of the bases and members declared in T. Add any
4748 implicitly-generated functions (like copy-constructors and
4749 assignment operators). Compute various flag bits (like
4750 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4751 level: i.e., independently of the ABI in use. */
4754 check_bases_and_members (tree t)
4756 /* Nonzero if the implicitly generated copy constructor should take
4757 a non-const reference argument. */
4758 int cant_have_const_ctor;
4759 /* Nonzero if the implicitly generated assignment operator
4760 should take a non-const reference argument. */
4761 int no_const_asn_ref;
4763 bool saved_complex_asn_ref;
4764 bool saved_nontrivial_dtor;
4767 /* By default, we use const reference arguments and generate default
4769 cant_have_const_ctor = 0;
4770 no_const_asn_ref = 0;
4772 /* Check all the base-classes. */
4773 check_bases (t, &cant_have_const_ctor,
4776 /* Check all the method declarations. */
4779 /* Save the initial values of these flags which only indicate whether
4780 or not the class has user-provided functions. As we analyze the
4781 bases and members we can set these flags for other reasons. */
4782 saved_complex_asn_ref = TYPE_HAS_COMPLEX_COPY_ASSIGN (t);
4783 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4785 /* Check all the data member declarations. We cannot call
4786 check_field_decls until we have called check_bases check_methods,
4787 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4788 being set appropriately. */
4789 check_field_decls (t, &access_decls,
4790 &cant_have_const_ctor,
4793 /* A nearly-empty class has to be vptr-containing; a nearly empty
4794 class contains just a vptr. */
4795 if (!TYPE_CONTAINS_VPTR_P (t))
4796 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4798 /* Do some bookkeeping that will guide the generation of implicitly
4799 declared member functions. */
4800 TYPE_HAS_COMPLEX_COPY_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4801 TYPE_HAS_COMPLEX_MOVE_CTOR (t) |= TYPE_CONTAINS_VPTR_P (t);
4802 /* We need to call a constructor for this class if it has a
4803 user-provided constructor, or if the default constructor is going
4804 to initialize the vptr. (This is not an if-and-only-if;
4805 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4806 themselves need constructing.) */
4807 TYPE_NEEDS_CONSTRUCTING (t)
4808 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4811 An aggregate is an array or a class with no user-provided
4812 constructors ... and no virtual functions.
4814 Again, other conditions for being an aggregate are checked
4816 CLASSTYPE_NON_AGGREGATE (t)
4817 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4818 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4819 retain the old definition internally for ABI reasons. */
4820 CLASSTYPE_NON_LAYOUT_POD_P (t)
4821 |= (CLASSTYPE_NON_AGGREGATE (t)
4822 || saved_nontrivial_dtor || saved_complex_asn_ref);
4823 CLASSTYPE_NON_STD_LAYOUT (t) |= TYPE_CONTAINS_VPTR_P (t);
4824 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4825 TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) |= TYPE_CONTAINS_VPTR_P (t);
4826 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4828 /* If the class has no user-declared constructor, but does have
4829 non-static const or reference data members that can never be
4830 initialized, issue a warning. */
4831 if (warn_uninitialized
4832 /* Classes with user-declared constructors are presumed to
4833 initialize these members. */
4834 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4835 /* Aggregates can be initialized with brace-enclosed
4837 && CLASSTYPE_NON_AGGREGATE (t))
4841 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
4845 if (TREE_CODE (field) != FIELD_DECL)
4848 type = TREE_TYPE (field);
4849 if (TREE_CODE (type) == REFERENCE_TYPE)
4850 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4851 "in class without a constructor", field);
4852 else if (CP_TYPE_CONST_P (type)
4853 && (!CLASS_TYPE_P (type)
4854 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4855 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4856 "in class without a constructor", field);
4860 /* Synthesize any needed methods. */
4861 add_implicitly_declared_members (t,
4862 cant_have_const_ctor,
4865 /* Check defaulted declarations here so we have cant_have_const_ctor
4866 and don't need to worry about clones. */
4867 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4868 if (DECL_DEFAULTED_IN_CLASS_P (fn))
4870 int copy = copy_fn_p (fn);
4874 = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor
4875 : !no_const_asn_ref);
4876 bool fn_const_p = (copy == 2);
4878 if (fn_const_p && !imp_const_p)
4879 /* If the function is defaulted outside the class, we just
4880 give the synthesis error. */
4881 error ("%q+D declared to take const reference, but implicit "
4882 "declaration would take non-const", fn);
4883 else if (imp_const_p && !fn_const_p)
4884 error ("%q+D declared to take non-const reference cannot be "
4885 "defaulted in the class body", fn);
4887 defaulted_late_check (fn);
4890 if (LAMBDA_TYPE_P (t))
4892 /* "The closure type associated with a lambda-expression has a deleted
4893 default constructor and a deleted copy assignment operator." */
4894 TYPE_NEEDS_CONSTRUCTING (t) = 1;
4895 TYPE_HAS_COMPLEX_DFLT (t) = 1;
4896 TYPE_HAS_COMPLEX_COPY_ASSIGN (t) = 1;
4897 CLASSTYPE_LAZY_MOVE_ASSIGN (t) = 0;
4899 /* "This class type is not an aggregate." */
4900 CLASSTYPE_NON_AGGREGATE (t) = 1;
4903 /* Compute the 'literal type' property before we
4904 do anything with non-static member functions. */
4905 finalize_literal_type_property (t);
4907 /* Create the in-charge and not-in-charge variants of constructors
4909 clone_constructors_and_destructors (t);
4911 /* Process the using-declarations. */
4912 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4913 handle_using_decl (TREE_VALUE (access_decls), t);
4915 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4916 finish_struct_methods (t);
4918 /* Figure out whether or not we will need a cookie when dynamically
4919 allocating an array of this type. */
4920 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4921 = type_requires_array_cookie (t);
4924 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4925 accordingly. If a new vfield was created (because T doesn't have a
4926 primary base class), then the newly created field is returned. It
4927 is not added to the TYPE_FIELDS list; it is the caller's
4928 responsibility to do that. Accumulate declared virtual functions
4932 create_vtable_ptr (tree t, tree* virtuals_p)
4936 /* Collect the virtual functions declared in T. */
4937 for (fn = TYPE_METHODS (t); fn; fn = DECL_CHAIN (fn))
4938 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4939 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4941 tree new_virtual = make_node (TREE_LIST);
4943 BV_FN (new_virtual) = fn;
4944 BV_DELTA (new_virtual) = integer_zero_node;
4945 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4947 TREE_CHAIN (new_virtual) = *virtuals_p;
4948 *virtuals_p = new_virtual;
4951 /* If we couldn't find an appropriate base class, create a new field
4952 here. Even if there weren't any new virtual functions, we might need a
4953 new virtual function table if we're supposed to include vptrs in
4954 all classes that need them. */
4955 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4957 /* We build this decl with vtbl_ptr_type_node, which is a
4958 `vtable_entry_type*'. It might seem more precise to use
4959 `vtable_entry_type (*)[N]' where N is the number of virtual
4960 functions. However, that would require the vtable pointer in
4961 base classes to have a different type than the vtable pointer
4962 in derived classes. We could make that happen, but that
4963 still wouldn't solve all the problems. In particular, the
4964 type-based alias analysis code would decide that assignments
4965 to the base class vtable pointer can't alias assignments to
4966 the derived class vtable pointer, since they have different
4967 types. Thus, in a derived class destructor, where the base
4968 class constructor was inlined, we could generate bad code for
4969 setting up the vtable pointer.
4971 Therefore, we use one type for all vtable pointers. We still
4972 use a type-correct type; it's just doesn't indicate the array
4973 bounds. That's better than using `void*' or some such; it's
4974 cleaner, and it let's the alias analysis code know that these
4975 stores cannot alias stores to void*! */
4978 field = build_decl (input_location,
4979 FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4980 DECL_VIRTUAL_P (field) = 1;
4981 DECL_ARTIFICIAL (field) = 1;
4982 DECL_FIELD_CONTEXT (field) = t;
4983 DECL_FCONTEXT (field) = t;
4984 if (TYPE_PACKED (t))
4985 DECL_PACKED (field) = 1;
4987 TYPE_VFIELD (t) = field;
4989 /* This class is non-empty. */
4990 CLASSTYPE_EMPTY_P (t) = 0;
4998 /* Add OFFSET to all base types of BINFO which is a base in the
4999 hierarchy dominated by T.
5001 OFFSET, which is a type offset, is number of bytes. */
5004 propagate_binfo_offsets (tree binfo, tree offset)
5010 /* Update BINFO's offset. */
5011 BINFO_OFFSET (binfo)
5012 = convert (sizetype,
5013 size_binop (PLUS_EXPR,
5014 convert (ssizetype, BINFO_OFFSET (binfo)),
5017 /* Find the primary base class. */
5018 primary_binfo = get_primary_binfo (binfo);
5020 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
5021 propagate_binfo_offsets (primary_binfo, offset);
5023 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
5025 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5027 /* Don't do the primary base twice. */
5028 if (base_binfo == primary_binfo)
5031 if (BINFO_VIRTUAL_P (base_binfo))
5034 propagate_binfo_offsets (base_binfo, offset);
5038 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
5039 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
5040 empty subobjects of T. */
5043 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
5047 bool first_vbase = true;
5050 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
5053 if (!abi_version_at_least(2))
5055 /* In G++ 3.2, we incorrectly rounded the size before laying out
5056 the virtual bases. */
5057 finish_record_layout (rli, /*free_p=*/false);
5058 #ifdef STRUCTURE_SIZE_BOUNDARY
5059 /* Packed structures don't need to have minimum size. */
5060 if (! TYPE_PACKED (t))
5061 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
5063 rli->offset = TYPE_SIZE_UNIT (t);
5064 rli->bitpos = bitsize_zero_node;
5065 rli->record_align = TYPE_ALIGN (t);
5068 /* Find the last field. The artificial fields created for virtual
5069 bases will go after the last extant field to date. */
5070 next_field = &TYPE_FIELDS (t);
5072 next_field = &DECL_CHAIN (*next_field);
5074 /* Go through the virtual bases, allocating space for each virtual
5075 base that is not already a primary base class. These are
5076 allocated in inheritance graph order. */
5077 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
5079 if (!BINFO_VIRTUAL_P (vbase))
5082 if (!BINFO_PRIMARY_P (vbase))
5084 tree basetype = TREE_TYPE (vbase);
5086 /* This virtual base is not a primary base of any class in the
5087 hierarchy, so we have to add space for it. */
5088 next_field = build_base_field (rli, vbase,
5089 offsets, next_field);
5091 /* If the first virtual base might have been placed at a
5092 lower address, had we started from CLASSTYPE_SIZE, rather
5093 than TYPE_SIZE, issue a warning. There can be both false
5094 positives and false negatives from this warning in rare
5095 cases; to deal with all the possibilities would probably
5096 require performing both layout algorithms and comparing
5097 the results which is not particularly tractable. */
5101 (size_binop (CEIL_DIV_EXPR,
5102 round_up_loc (input_location,
5104 CLASSTYPE_ALIGN (basetype)),
5106 BINFO_OFFSET (vbase))))
5108 "offset of virtual base %qT is not ABI-compliant and "
5109 "may change in a future version of GCC",
5112 first_vbase = false;
5117 /* Returns the offset of the byte just past the end of the base class
5121 end_of_base (tree binfo)
5125 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
5126 size = TYPE_SIZE_UNIT (char_type_node);
5127 else if (is_empty_class (BINFO_TYPE (binfo)))
5128 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
5129 allocate some space for it. It cannot have virtual bases, so
5130 TYPE_SIZE_UNIT is fine. */
5131 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5133 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
5135 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
5138 /* Returns the offset of the byte just past the end of the base class
5139 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
5140 only non-virtual bases are included. */
5143 end_of_class (tree t, int include_virtuals_p)
5145 tree result = size_zero_node;
5146 VEC(tree,gc) *vbases;
5152 for (binfo = TYPE_BINFO (t), i = 0;
5153 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5155 if (!include_virtuals_p
5156 && BINFO_VIRTUAL_P (base_binfo)
5157 && (!BINFO_PRIMARY_P (base_binfo)
5158 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
5161 offset = end_of_base (base_binfo);
5162 if (INT_CST_LT_UNSIGNED (result, offset))
5166 /* G++ 3.2 did not check indirect virtual bases. */
5167 if (abi_version_at_least (2) && include_virtuals_p)
5168 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5169 VEC_iterate (tree, vbases, i, base_binfo); i++)
5171 offset = end_of_base (base_binfo);
5172 if (INT_CST_LT_UNSIGNED (result, offset))
5179 /* Warn about bases of T that are inaccessible because they are
5180 ambiguous. For example:
5183 struct T : public S {};
5184 struct U : public S, public T {};
5186 Here, `(S*) new U' is not allowed because there are two `S'
5190 warn_about_ambiguous_bases (tree t)
5193 VEC(tree,gc) *vbases;
5198 /* If there are no repeated bases, nothing can be ambiguous. */
5199 if (!CLASSTYPE_REPEATED_BASE_P (t))
5202 /* Check direct bases. */
5203 for (binfo = TYPE_BINFO (t), i = 0;
5204 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
5206 basetype = BINFO_TYPE (base_binfo);
5208 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5209 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
5213 /* Check for ambiguous virtual bases. */
5215 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
5216 VEC_iterate (tree, vbases, i, binfo); i++)
5218 basetype = BINFO_TYPE (binfo);
5220 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
5221 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
5226 /* Compare two INTEGER_CSTs K1 and K2. */
5229 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
5231 return tree_int_cst_compare ((tree) k1, (tree) k2);
5234 /* Increase the size indicated in RLI to account for empty classes
5235 that are "off the end" of the class. */
5238 include_empty_classes (record_layout_info rli)
5243 /* It might be the case that we grew the class to allocate a
5244 zero-sized base class. That won't be reflected in RLI, yet,
5245 because we are willing to overlay multiple bases at the same
5246 offset. However, now we need to make sure that RLI is big enough
5247 to reflect the entire class. */
5248 eoc = end_of_class (rli->t,
5249 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
5250 rli_size = rli_size_unit_so_far (rli);
5251 if (TREE_CODE (rli_size) == INTEGER_CST
5252 && INT_CST_LT_UNSIGNED (rli_size, eoc))
5254 if (!abi_version_at_least (2))
5255 /* In version 1 of the ABI, the size of a class that ends with
5256 a bitfield was not rounded up to a whole multiple of a
5257 byte. Because rli_size_unit_so_far returns only the number
5258 of fully allocated bytes, any extra bits were not included
5260 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
5262 /* The size should have been rounded to a whole byte. */
5263 gcc_assert (tree_int_cst_equal
5264 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
5266 = size_binop (PLUS_EXPR,
5268 size_binop (MULT_EXPR,
5269 convert (bitsizetype,
5270 size_binop (MINUS_EXPR,
5272 bitsize_int (BITS_PER_UNIT)));
5273 normalize_rli (rli);
5277 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
5278 BINFO_OFFSETs for all of the base-classes. Position the vtable
5279 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
5282 layout_class_type (tree t, tree *virtuals_p)
5284 tree non_static_data_members;
5287 record_layout_info rli;
5288 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
5289 types that appear at that offset. */
5290 splay_tree empty_base_offsets;
5291 /* True if the last field layed out was a bit-field. */
5292 bool last_field_was_bitfield = false;
5293 /* The location at which the next field should be inserted. */
5295 /* T, as a base class. */
5298 /* Keep track of the first non-static data member. */
5299 non_static_data_members = TYPE_FIELDS (t);
5301 /* Start laying out the record. */
5302 rli = start_record_layout (t);
5304 /* Mark all the primary bases in the hierarchy. */
5305 determine_primary_bases (t);
5307 /* Create a pointer to our virtual function table. */
5308 vptr = create_vtable_ptr (t, virtuals_p);
5310 /* The vptr is always the first thing in the class. */
5313 DECL_CHAIN (vptr) = TYPE_FIELDS (t);
5314 TYPE_FIELDS (t) = vptr;
5315 next_field = &DECL_CHAIN (vptr);
5316 place_field (rli, vptr);
5319 next_field = &TYPE_FIELDS (t);
5321 /* Build FIELD_DECLs for all of the non-virtual base-types. */
5322 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
5324 build_base_fields (rli, empty_base_offsets, next_field);
5326 /* Layout the non-static data members. */
5327 for (field = non_static_data_members; field; field = DECL_CHAIN (field))
5332 /* We still pass things that aren't non-static data members to
5333 the back end, in case it wants to do something with them. */
5334 if (TREE_CODE (field) != FIELD_DECL)
5336 place_field (rli, field);
5337 /* If the static data member has incomplete type, keep track
5338 of it so that it can be completed later. (The handling
5339 of pending statics in finish_record_layout is
5340 insufficient; consider:
5343 struct S2 { static S1 s1; };
5345 At this point, finish_record_layout will be called, but
5346 S1 is still incomplete.) */
5347 if (TREE_CODE (field) == VAR_DECL)
5349 maybe_register_incomplete_var (field);
5350 /* The visibility of static data members is determined
5351 at their point of declaration, not their point of
5353 determine_visibility (field);
5358 type = TREE_TYPE (field);
5359 if (type == error_mark_node)
5362 padding = NULL_TREE;
5364 /* If this field is a bit-field whose width is greater than its
5365 type, then there are some special rules for allocating
5367 if (DECL_C_BIT_FIELD (field)
5368 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
5372 bool was_unnamed_p = false;
5373 /* We must allocate the bits as if suitably aligned for the
5374 longest integer type that fits in this many bits. type
5375 of the field. Then, we are supposed to use the left over
5376 bits as additional padding. */
5377 for (itk = itk_char; itk != itk_none; ++itk)
5378 if (integer_types[itk] != NULL_TREE
5379 && (INT_CST_LT (size_int (MAX_FIXED_MODE_SIZE),
5380 TYPE_SIZE (integer_types[itk]))
5381 || INT_CST_LT (DECL_SIZE (field),
5382 TYPE_SIZE (integer_types[itk]))))
5385 /* ITK now indicates a type that is too large for the
5386 field. We have to back up by one to find the largest
5391 integer_type = integer_types[itk];
5392 } while (itk > 0 && integer_type == NULL_TREE);
5394 /* Figure out how much additional padding is required. GCC
5395 3.2 always created a padding field, even if it had zero
5397 if (!abi_version_at_least (2)
5398 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
5400 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
5401 /* In a union, the padding field must have the full width
5402 of the bit-field; all fields start at offset zero. */
5403 padding = DECL_SIZE (field);
5406 if (TREE_CODE (t) == UNION_TYPE)
5407 warning (OPT_Wabi, "size assigned to %qT may not be "
5408 "ABI-compliant and may change in a future "
5411 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
5412 TYPE_SIZE (integer_type));
5415 #ifdef PCC_BITFIELD_TYPE_MATTERS
5416 /* An unnamed bitfield does not normally affect the
5417 alignment of the containing class on a target where
5418 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5419 make any exceptions for unnamed bitfields when the
5420 bitfields are longer than their types. Therefore, we
5421 temporarily give the field a name. */
5422 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
5424 was_unnamed_p = true;
5425 DECL_NAME (field) = make_anon_name ();
5428 DECL_SIZE (field) = TYPE_SIZE (integer_type);
5429 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
5430 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
5431 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5432 empty_base_offsets);
5434 DECL_NAME (field) = NULL_TREE;
5435 /* Now that layout has been performed, set the size of the
5436 field to the size of its declared type; the rest of the
5437 field is effectively invisible. */
5438 DECL_SIZE (field) = TYPE_SIZE (type);
5439 /* We must also reset the DECL_MODE of the field. */
5440 if (abi_version_at_least (2))
5441 DECL_MODE (field) = TYPE_MODE (type);
5443 && DECL_MODE (field) != TYPE_MODE (type))
5444 /* Versions of G++ before G++ 3.4 did not reset the
5447 "the offset of %qD may not be ABI-compliant and may "
5448 "change in a future version of GCC", field);
5451 layout_nonempty_base_or_field (rli, field, NULL_TREE,
5452 empty_base_offsets);
5454 /* Remember the location of any empty classes in FIELD. */
5455 if (abi_version_at_least (2))
5456 record_subobject_offsets (TREE_TYPE (field),
5457 byte_position(field),
5459 /*is_data_member=*/true);
5461 /* If a bit-field does not immediately follow another bit-field,
5462 and yet it starts in the middle of a byte, we have failed to
5463 comply with the ABI. */
5465 && DECL_C_BIT_FIELD (field)
5466 /* The TREE_NO_WARNING flag gets set by Objective-C when
5467 laying out an Objective-C class. The ObjC ABI differs
5468 from the C++ ABI, and so we do not want a warning
5470 && !TREE_NO_WARNING (field)
5471 && !last_field_was_bitfield
5472 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
5473 DECL_FIELD_BIT_OFFSET (field),
5474 bitsize_unit_node)))
5475 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
5476 "change in a future version of GCC", field);
5478 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5479 offset of the field. */
5481 && !abi_version_at_least (2)
5482 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
5483 byte_position (field))
5484 && contains_empty_class_p (TREE_TYPE (field)))
5485 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
5486 "classes to be placed at different locations in a "
5487 "future version of GCC", field);
5489 /* The middle end uses the type of expressions to determine the
5490 possible range of expression values. In order to optimize
5491 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5492 must be made aware of the width of "i", via its type.
5494 Because C++ does not have integer types of arbitrary width,
5495 we must (for the purposes of the front end) convert from the
5496 type assigned here to the declared type of the bitfield
5497 whenever a bitfield expression is used as an rvalue.
5498 Similarly, when assigning a value to a bitfield, the value
5499 must be converted to the type given the bitfield here. */
5500 if (DECL_C_BIT_FIELD (field))
5502 unsigned HOST_WIDE_INT width;
5503 tree ftype = TREE_TYPE (field);
5504 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
5505 if (width != TYPE_PRECISION (ftype))
5508 = c_build_bitfield_integer_type (width,
5509 TYPE_UNSIGNED (ftype));
5511 = cp_build_qualified_type (TREE_TYPE (field),
5512 cp_type_quals (ftype));
5516 /* If we needed additional padding after this field, add it
5522 padding_field = build_decl (input_location,
5526 DECL_BIT_FIELD (padding_field) = 1;
5527 DECL_SIZE (padding_field) = padding;
5528 DECL_CONTEXT (padding_field) = t;
5529 DECL_ARTIFICIAL (padding_field) = 1;
5530 DECL_IGNORED_P (padding_field) = 1;
5531 layout_nonempty_base_or_field (rli, padding_field,
5533 empty_base_offsets);
5536 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5539 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5541 /* Make sure that we are on a byte boundary so that the size of
5542 the class without virtual bases will always be a round number
5544 rli->bitpos = round_up_loc (input_location, rli->bitpos, BITS_PER_UNIT);
5545 normalize_rli (rli);
5548 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5550 if (!abi_version_at_least (2))
5551 include_empty_classes(rli);
5553 /* Delete all zero-width bit-fields from the list of fields. Now
5554 that the type is laid out they are no longer important. */
5555 remove_zero_width_bit_fields (t);
5557 /* Create the version of T used for virtual bases. We do not use
5558 make_class_type for this version; this is an artificial type. For
5559 a POD type, we just reuse T. */
5560 if (CLASSTYPE_NON_LAYOUT_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5562 base_t = make_node (TREE_CODE (t));
5564 /* Set the size and alignment for the new type. In G++ 3.2, all
5565 empty classes were considered to have size zero when used as
5567 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5569 TYPE_SIZE (base_t) = bitsize_zero_node;
5570 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5571 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5573 "layout of classes derived from empty class %qT "
5574 "may change in a future version of GCC",
5581 /* If the ABI version is not at least two, and the last
5582 field was a bit-field, RLI may not be on a byte
5583 boundary. In particular, rli_size_unit_so_far might
5584 indicate the last complete byte, while rli_size_so_far
5585 indicates the total number of bits used. Therefore,
5586 rli_size_so_far, rather than rli_size_unit_so_far, is
5587 used to compute TYPE_SIZE_UNIT. */
5588 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5589 TYPE_SIZE_UNIT (base_t)
5590 = size_binop (MAX_EXPR,
5592 size_binop (CEIL_DIV_EXPR,
5593 rli_size_so_far (rli),
5594 bitsize_int (BITS_PER_UNIT))),
5597 = size_binop (MAX_EXPR,
5598 rli_size_so_far (rli),
5599 size_binop (MULT_EXPR,
5600 convert (bitsizetype, eoc),
5601 bitsize_int (BITS_PER_UNIT)));
5603 TYPE_ALIGN (base_t) = rli->record_align;
5604 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5606 /* Copy the fields from T. */
5607 next_field = &TYPE_FIELDS (base_t);
5608 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5609 if (TREE_CODE (field) == FIELD_DECL)
5611 *next_field = build_decl (input_location,
5615 DECL_CONTEXT (*next_field) = base_t;
5616 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5617 DECL_FIELD_BIT_OFFSET (*next_field)
5618 = DECL_FIELD_BIT_OFFSET (field);
5619 DECL_SIZE (*next_field) = DECL_SIZE (field);
5620 DECL_MODE (*next_field) = DECL_MODE (field);
5621 next_field = &DECL_CHAIN (*next_field);
5624 /* Record the base version of the type. */
5625 CLASSTYPE_AS_BASE (t) = base_t;
5626 TYPE_CONTEXT (base_t) = t;
5629 CLASSTYPE_AS_BASE (t) = t;
5631 /* Every empty class contains an empty class. */
5632 if (CLASSTYPE_EMPTY_P (t))
5633 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5635 /* Set the TYPE_DECL for this type to contain the right
5636 value for DECL_OFFSET, so that we can use it as part
5637 of a COMPONENT_REF for multiple inheritance. */
5638 layout_decl (TYPE_MAIN_DECL (t), 0);
5640 /* Now fix up any virtual base class types that we left lying
5641 around. We must get these done before we try to lay out the
5642 virtual function table. As a side-effect, this will remove the
5643 base subobject fields. */
5644 layout_virtual_bases (rli, empty_base_offsets);
5646 /* Make sure that empty classes are reflected in RLI at this
5648 include_empty_classes(rli);
5650 /* Make sure not to create any structures with zero size. */
5651 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5653 build_decl (input_location,
5654 FIELD_DECL, NULL_TREE, char_type_node));
5656 /* If this is a non-POD, declaring it packed makes a difference to how it
5657 can be used as a field; don't let finalize_record_size undo it. */
5658 if (TYPE_PACKED (t) && !layout_pod_type_p (t))
5659 rli->packed_maybe_necessary = true;
5661 /* Let the back end lay out the type. */
5662 finish_record_layout (rli, /*free_p=*/true);
5664 /* Warn about bases that can't be talked about due to ambiguity. */
5665 warn_about_ambiguous_bases (t);
5667 /* Now that we're done with layout, give the base fields the real types. */
5668 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
5669 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5670 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5673 splay_tree_delete (empty_base_offsets);
5675 if (CLASSTYPE_EMPTY_P (t)
5676 && tree_int_cst_lt (sizeof_biggest_empty_class,
5677 TYPE_SIZE_UNIT (t)))
5678 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5681 /* Determine the "key method" for the class type indicated by TYPE,
5682 and set CLASSTYPE_KEY_METHOD accordingly. */
5685 determine_key_method (tree type)
5689 if (TYPE_FOR_JAVA (type)
5690 || processing_template_decl
5691 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5692 || CLASSTYPE_INTERFACE_KNOWN (type))
5695 /* The key method is the first non-pure virtual function that is not
5696 inline at the point of class definition. On some targets the
5697 key function may not be inline; those targets should not call
5698 this function until the end of the translation unit. */
5699 for (method = TYPE_METHODS (type); method != NULL_TREE;
5700 method = DECL_CHAIN (method))
5701 if (DECL_VINDEX (method) != NULL_TREE
5702 && ! DECL_DECLARED_INLINE_P (method)
5703 && ! DECL_PURE_VIRTUAL_P (method))
5705 CLASSTYPE_KEY_METHOD (type) = method;
5713 /* Allocate and return an instance of struct sorted_fields_type with
5716 static struct sorted_fields_type *
5717 sorted_fields_type_new (int n)
5719 struct sorted_fields_type *sft;
5720 sft = ggc_alloc_sorted_fields_type (sizeof (struct sorted_fields_type)
5721 + n * sizeof (tree));
5728 /* Perform processing required when the definition of T (a class type)
5732 finish_struct_1 (tree t)
5735 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5736 tree virtuals = NULL_TREE;
5739 if (COMPLETE_TYPE_P (t))
5741 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5742 error ("redefinition of %q#T", t);
5747 /* If this type was previously laid out as a forward reference,
5748 make sure we lay it out again. */
5749 TYPE_SIZE (t) = NULL_TREE;
5750 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5752 /* Make assumptions about the class; we'll reset the flags if
5754 CLASSTYPE_EMPTY_P (t) = 1;
5755 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5756 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5757 CLASSTYPE_LITERAL_P (t) = true;
5759 /* Do end-of-class semantic processing: checking the validity of the
5760 bases and members and add implicitly generated methods. */
5761 check_bases_and_members (t);
5763 /* Find the key method. */
5764 if (TYPE_CONTAINS_VPTR_P (t))
5766 /* The Itanium C++ ABI permits the key method to be chosen when
5767 the class is defined -- even though the key method so
5768 selected may later turn out to be an inline function. On
5769 some systems (such as ARM Symbian OS) the key method cannot
5770 be determined until the end of the translation unit. On such
5771 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5772 will cause the class to be added to KEYED_CLASSES. Then, in
5773 finish_file we will determine the key method. */
5774 if (targetm.cxx.key_method_may_be_inline ())
5775 determine_key_method (t);
5777 /* If a polymorphic class has no key method, we may emit the vtable
5778 in every translation unit where the class definition appears. */
5779 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5780 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5783 /* Layout the class itself. */
5784 layout_class_type (t, &virtuals);
5785 if (CLASSTYPE_AS_BASE (t) != t)
5786 /* We use the base type for trivial assignments, and hence it
5788 compute_record_mode (CLASSTYPE_AS_BASE (t));
5790 virtuals = modify_all_vtables (t, nreverse (virtuals));
5792 /* If necessary, create the primary vtable for this class. */
5793 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5795 /* We must enter these virtuals into the table. */
5796 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5797 build_primary_vtable (NULL_TREE, t);
5798 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5799 /* Here we know enough to change the type of our virtual
5800 function table, but we will wait until later this function. */
5801 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5804 if (TYPE_CONTAINS_VPTR_P (t))
5809 if (BINFO_VTABLE (TYPE_BINFO (t)))
5810 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5811 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5812 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5814 /* Add entries for virtual functions introduced by this class. */
5815 BINFO_VIRTUALS (TYPE_BINFO (t))
5816 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5818 /* Set DECL_VINDEX for all functions declared in this class. */
5819 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5821 fn = TREE_CHAIN (fn),
5822 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5823 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5825 tree fndecl = BV_FN (fn);
5827 if (DECL_THUNK_P (fndecl))
5828 /* A thunk. We should never be calling this entry directly
5829 from this vtable -- we'd use the entry for the non
5830 thunk base function. */
5831 DECL_VINDEX (fndecl) = NULL_TREE;
5832 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5833 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5837 finish_struct_bits (t);
5839 /* Complete the rtl for any static member objects of the type we're
5841 for (x = TYPE_FIELDS (t); x; x = DECL_CHAIN (x))
5842 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5843 && TREE_TYPE (x) != error_mark_node
5844 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5845 DECL_MODE (x) = TYPE_MODE (t);
5847 /* Done with FIELDS...now decide whether to sort these for
5848 faster lookups later.
5850 We use a small number because most searches fail (succeeding
5851 ultimately as the search bores through the inheritance
5852 hierarchy), and we want this failure to occur quickly. */
5854 n_fields = count_fields (TYPE_FIELDS (t));
5857 struct sorted_fields_type *field_vec = sorted_fields_type_new (n_fields);
5858 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5859 qsort (field_vec->elts, n_fields, sizeof (tree),
5861 CLASSTYPE_SORTED_FIELDS (t) = field_vec;
5864 /* Complain if one of the field types requires lower visibility. */
5865 constrain_class_visibility (t);
5867 /* Make the rtl for any new vtables we have created, and unmark
5868 the base types we marked. */
5871 /* Build the VTT for T. */
5874 /* This warning does not make sense for Java classes, since they
5875 cannot have destructors. */
5876 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5880 dtor = CLASSTYPE_DESTRUCTORS (t);
5881 if (/* An implicitly declared destructor is always public. And,
5882 if it were virtual, we would have created it by now. */
5884 || (!DECL_VINDEX (dtor)
5885 && (/* public non-virtual */
5886 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5887 || (/* non-public non-virtual with friends */
5888 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5889 && (CLASSTYPE_FRIEND_CLASSES (t)
5890 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5891 warning (OPT_Wnon_virtual_dtor,
5892 "%q#T has virtual functions and accessible"
5893 " non-virtual destructor", t);
5898 if (warn_overloaded_virtual)
5901 /* Class layout, assignment of virtual table slots, etc., is now
5902 complete. Give the back end a chance to tweak the visibility of
5903 the class or perform any other required target modifications. */
5904 targetm.cxx.adjust_class_at_definition (t);
5906 maybe_suppress_debug_info (t);
5908 dump_class_hierarchy (t);
5910 /* Finish debugging output for this type. */
5911 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5913 if (TYPE_TRANSPARENT_AGGR (t))
5915 tree field = first_field (t);
5916 if (field == NULL_TREE || error_operand_p (field))
5918 error ("type transparent class %qT does not have any fields", t);
5919 TYPE_TRANSPARENT_AGGR (t) = 0;
5921 else if (DECL_ARTIFICIAL (field))
5923 if (DECL_FIELD_IS_BASE (field))
5924 error ("type transparent class %qT has base classes", t);
5927 gcc_checking_assert (DECL_VIRTUAL_P (field));
5928 error ("type transparent class %qT has virtual functions", t);
5930 TYPE_TRANSPARENT_AGGR (t) = 0;
5935 /* When T was built up, the member declarations were added in reverse
5936 order. Rearrange them to declaration order. */
5939 unreverse_member_declarations (tree t)
5945 /* The following lists are all in reverse order. Put them in
5946 declaration order now. */
5947 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5948 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5950 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5951 reverse order, so we can't just use nreverse. */
5953 for (x = TYPE_FIELDS (t);
5954 x && TREE_CODE (x) != TYPE_DECL;
5957 next = DECL_CHAIN (x);
5958 DECL_CHAIN (x) = prev;
5963 DECL_CHAIN (TYPE_FIELDS (t)) = x;
5965 TYPE_FIELDS (t) = prev;
5970 finish_struct (tree t, tree attributes)
5972 location_t saved_loc = input_location;
5974 /* Now that we've got all the field declarations, reverse everything
5976 unreverse_member_declarations (t);
5978 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5980 /* Nadger the current location so that diagnostics point to the start of
5981 the struct, not the end. */
5982 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5984 if (processing_template_decl)
5988 finish_struct_methods (t);
5989 TYPE_SIZE (t) = bitsize_zero_node;
5990 TYPE_SIZE_UNIT (t) = size_zero_node;
5992 /* We need to emit an error message if this type was used as a parameter
5993 and it is an abstract type, even if it is a template. We construct
5994 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5995 account and we call complete_vars with this type, which will check
5996 the PARM_DECLS. Note that while the type is being defined,
5997 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5998 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5999 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
6000 for (x = TYPE_METHODS (t); x; x = DECL_CHAIN (x))
6001 if (DECL_PURE_VIRTUAL_P (x))
6002 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
6005 /* Remember current #pragma pack value. */
6006 TYPE_PRECISION (t) = maximum_field_alignment;
6009 finish_struct_1 (t);
6011 input_location = saved_loc;
6013 TYPE_BEING_DEFINED (t) = 0;
6015 if (current_class_type)
6018 error ("trying to finish struct, but kicked out due to previous parse errors");
6020 if (processing_template_decl && at_function_scope_p ())
6021 add_stmt (build_min (TAG_DEFN, t));
6026 /* Return the dynamic type of INSTANCE, if known.
6027 Used to determine whether the virtual function table is needed
6030 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6031 of our knowledge of its type. *NONNULL should be initialized
6032 before this function is called. */
6035 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
6037 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
6039 switch (TREE_CODE (instance))
6042 if (POINTER_TYPE_P (TREE_TYPE (instance)))
6045 return RECUR (TREE_OPERAND (instance, 0));
6048 /* This is a call to a constructor, hence it's never zero. */
6049 if (TREE_HAS_CONSTRUCTOR (instance))
6053 return TREE_TYPE (instance);
6058 /* This is a call to a constructor, hence it's never zero. */
6059 if (TREE_HAS_CONSTRUCTOR (instance))
6063 return TREE_TYPE (instance);
6065 return RECUR (TREE_OPERAND (instance, 0));
6067 case POINTER_PLUS_EXPR:
6070 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
6071 return RECUR (TREE_OPERAND (instance, 0));
6072 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
6073 /* Propagate nonnull. */
6074 return RECUR (TREE_OPERAND (instance, 0));
6079 return RECUR (TREE_OPERAND (instance, 0));
6082 instance = TREE_OPERAND (instance, 0);
6085 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
6086 with a real object -- given &p->f, p can still be null. */
6087 tree t = get_base_address (instance);
6088 /* ??? Probably should check DECL_WEAK here. */
6089 if (t && DECL_P (t))
6092 return RECUR (instance);
6095 /* If this component is really a base class reference, then the field
6096 itself isn't definitive. */
6097 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
6098 return RECUR (TREE_OPERAND (instance, 0));
6099 return RECUR (TREE_OPERAND (instance, 1));
6103 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
6104 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
6108 return TREE_TYPE (TREE_TYPE (instance));
6110 /* fall through... */
6114 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
6118 return TREE_TYPE (instance);
6120 else if (instance == current_class_ptr)
6125 /* if we're in a ctor or dtor, we know our type. If
6126 current_class_ptr is set but we aren't in a function, we're in
6127 an NSDMI (and therefore a constructor). */
6128 if (current_scope () != current_function_decl
6129 || (DECL_LANG_SPECIFIC (current_function_decl)
6130 && (DECL_CONSTRUCTOR_P (current_function_decl)
6131 || DECL_DESTRUCTOR_P (current_function_decl))))
6135 return TREE_TYPE (TREE_TYPE (instance));
6138 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
6140 /* We only need one hash table because it is always left empty. */
6143 ht = htab_create (37,
6148 /* Reference variables should be references to objects. */
6152 /* Enter the INSTANCE in a table to prevent recursion; a
6153 variable's initializer may refer to the variable
6155 if (TREE_CODE (instance) == VAR_DECL
6156 && DECL_INITIAL (instance)
6157 && !type_dependent_expression_p_push (DECL_INITIAL (instance))
6158 && !htab_find (ht, instance))
6163 slot = htab_find_slot (ht, instance, INSERT);
6165 type = RECUR (DECL_INITIAL (instance));
6166 htab_remove_elt (ht, instance);
6179 /* Return nonzero if the dynamic type of INSTANCE is known, and
6180 equivalent to the static type. We also handle the case where
6181 INSTANCE is really a pointer. Return negative if this is a
6182 ctor/dtor. There the dynamic type is known, but this might not be
6183 the most derived base of the original object, and hence virtual
6184 bases may not be layed out according to this type.
6186 Used to determine whether the virtual function table is needed
6189 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
6190 of our knowledge of its type. *NONNULL should be initialized
6191 before this function is called. */
6194 resolves_to_fixed_type_p (tree instance, int* nonnull)
6196 tree t = TREE_TYPE (instance);
6200 if (processing_template_decl)
6202 /* In a template we only care about the type of the result. */
6208 fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
6209 if (fixed == NULL_TREE)
6211 if (POINTER_TYPE_P (t))
6213 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
6215 return cdtorp ? -1 : 1;
6220 init_class_processing (void)
6222 current_class_depth = 0;
6223 current_class_stack_size = 10;
6225 = XNEWVEC (struct class_stack_node, current_class_stack_size);
6226 local_classes = VEC_alloc (tree, gc, 8);
6227 sizeof_biggest_empty_class = size_zero_node;
6229 ridpointers[(int) RID_PUBLIC] = access_public_node;
6230 ridpointers[(int) RID_PRIVATE] = access_private_node;
6231 ridpointers[(int) RID_PROTECTED] = access_protected_node;
6234 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
6237 restore_class_cache (void)
6241 /* We are re-entering the same class we just left, so we don't
6242 have to search the whole inheritance matrix to find all the
6243 decls to bind again. Instead, we install the cached
6244 class_shadowed list and walk through it binding names. */
6245 push_binding_level (previous_class_level);
6246 class_binding_level = previous_class_level;
6247 /* Restore IDENTIFIER_TYPE_VALUE. */
6248 for (type = class_binding_level->type_shadowed;
6250 type = TREE_CHAIN (type))
6251 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
6254 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
6255 appropriate for TYPE.
6257 So that we may avoid calls to lookup_name, we cache the _TYPE
6258 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
6260 For multiple inheritance, we perform a two-pass depth-first search
6261 of the type lattice. */
6264 pushclass (tree type)
6266 class_stack_node_t csn;
6268 type = TYPE_MAIN_VARIANT (type);
6270 /* Make sure there is enough room for the new entry on the stack. */
6271 if (current_class_depth + 1 >= current_class_stack_size)
6273 current_class_stack_size *= 2;
6275 = XRESIZEVEC (struct class_stack_node, current_class_stack,
6276 current_class_stack_size);
6279 /* Insert a new entry on the class stack. */
6280 csn = current_class_stack + current_class_depth;
6281 csn->name = current_class_name;
6282 csn->type = current_class_type;
6283 csn->access = current_access_specifier;
6284 csn->names_used = 0;
6286 current_class_depth++;
6288 /* Now set up the new type. */
6289 current_class_name = TYPE_NAME (type);
6290 if (TREE_CODE (current_class_name) == TYPE_DECL)
6291 current_class_name = DECL_NAME (current_class_name);
6292 current_class_type = type;
6294 /* By default, things in classes are private, while things in
6295 structures or unions are public. */
6296 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
6297 ? access_private_node
6298 : access_public_node);
6300 if (previous_class_level
6301 && type != previous_class_level->this_entity
6302 && current_class_depth == 1)
6304 /* Forcibly remove any old class remnants. */
6305 invalidate_class_lookup_cache ();
6308 if (!previous_class_level
6309 || type != previous_class_level->this_entity
6310 || current_class_depth > 1)
6313 restore_class_cache ();
6316 /* When we exit a toplevel class scope, we save its binding level so
6317 that we can restore it quickly. Here, we've entered some other
6318 class, so we must invalidate our cache. */
6321 invalidate_class_lookup_cache (void)
6323 previous_class_level = NULL;
6326 /* Get out of the current class scope. If we were in a class scope
6327 previously, that is the one popped to. */
6334 current_class_depth--;
6335 current_class_name = current_class_stack[current_class_depth].name;
6336 current_class_type = current_class_stack[current_class_depth].type;
6337 current_access_specifier = current_class_stack[current_class_depth].access;
6338 if (current_class_stack[current_class_depth].names_used)
6339 splay_tree_delete (current_class_stack[current_class_depth].names_used);
6342 /* Mark the top of the class stack as hidden. */
6345 push_class_stack (void)
6347 if (current_class_depth)
6348 ++current_class_stack[current_class_depth - 1].hidden;
6351 /* Mark the top of the class stack as un-hidden. */
6354 pop_class_stack (void)
6356 if (current_class_depth)
6357 --current_class_stack[current_class_depth - 1].hidden;
6360 /* Returns 1 if the class type currently being defined is either T or
6361 a nested type of T. */
6364 currently_open_class (tree t)
6368 if (!CLASS_TYPE_P (t))
6371 t = TYPE_MAIN_VARIANT (t);
6373 /* We start looking from 1 because entry 0 is from global scope,
6375 for (i = current_class_depth; i > 0; --i)
6378 if (i == current_class_depth)
6379 c = current_class_type;
6382 if (current_class_stack[i].hidden)
6384 c = current_class_stack[i].type;
6388 if (same_type_p (c, t))
6394 /* If either current_class_type or one of its enclosing classes are derived
6395 from T, return the appropriate type. Used to determine how we found
6396 something via unqualified lookup. */
6399 currently_open_derived_class (tree t)
6403 /* The bases of a dependent type are unknown. */
6404 if (dependent_type_p (t))
6407 if (!current_class_type)
6410 if (DERIVED_FROM_P (t, current_class_type))
6411 return current_class_type;
6413 for (i = current_class_depth - 1; i > 0; --i)
6415 if (current_class_stack[i].hidden)
6417 if (DERIVED_FROM_P (t, current_class_stack[i].type))
6418 return current_class_stack[i].type;
6424 /* Returns the innermost class type which is not a lambda closure type. */
6427 current_nonlambda_class_type (void)
6431 /* We start looking from 1 because entry 0 is from global scope,
6433 for (i = current_class_depth; i > 0; --i)
6436 if (i == current_class_depth)
6437 c = current_class_type;
6440 if (current_class_stack[i].hidden)
6442 c = current_class_stack[i].type;
6446 if (!LAMBDA_TYPE_P (c))
6452 /* When entering a class scope, all enclosing class scopes' names with
6453 static meaning (static variables, static functions, types and
6454 enumerators) have to be visible. This recursive function calls
6455 pushclass for all enclosing class contexts until global or a local
6456 scope is reached. TYPE is the enclosed class. */
6459 push_nested_class (tree type)
6461 /* A namespace might be passed in error cases, like A::B:C. */
6462 if (type == NULL_TREE
6463 || !CLASS_TYPE_P (type))
6466 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
6471 /* Undoes a push_nested_class call. */
6474 pop_nested_class (void)
6476 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
6479 if (context && CLASS_TYPE_P (context))
6480 pop_nested_class ();
6483 /* Returns the number of extern "LANG" blocks we are nested within. */
6486 current_lang_depth (void)
6488 return VEC_length (tree, current_lang_base);
6491 /* Set global variables CURRENT_LANG_NAME to appropriate value
6492 so that behavior of name-mangling machinery is correct. */
6495 push_lang_context (tree name)
6497 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
6499 if (name == lang_name_cplusplus)
6501 current_lang_name = name;
6503 else if (name == lang_name_java)
6505 current_lang_name = name;
6506 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6507 (See record_builtin_java_type in decl.c.) However, that causes
6508 incorrect debug entries if these types are actually used.
6509 So we re-enable debug output after extern "Java". */
6510 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
6511 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
6512 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
6513 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
6514 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
6515 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
6516 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
6517 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
6519 else if (name == lang_name_c)
6521 current_lang_name = name;
6524 error ("language string %<\"%E\"%> not recognized", name);
6527 /* Get out of the current language scope. */
6530 pop_lang_context (void)
6532 current_lang_name = VEC_pop (tree, current_lang_base);
6535 /* Type instantiation routines. */
6537 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6538 matches the TARGET_TYPE. If there is no satisfactory match, return
6539 error_mark_node, and issue an error & warning messages under
6540 control of FLAGS. Permit pointers to member function if FLAGS
6541 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6542 a template-id, and EXPLICIT_TARGS are the explicitly provided
6545 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6546 is the base path used to reference those member functions. If
6547 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6548 resolved to a member function, access checks will be performed and
6549 errors issued if appropriate. */
6552 resolve_address_of_overloaded_function (tree target_type,
6554 tsubst_flags_t flags,
6556 tree explicit_targs,
6559 /* Here's what the standard says:
6563 If the name is a function template, template argument deduction
6564 is done, and if the argument deduction succeeds, the deduced
6565 arguments are used to generate a single template function, which
6566 is added to the set of overloaded functions considered.
6568 Non-member functions and static member functions match targets of
6569 type "pointer-to-function" or "reference-to-function." Nonstatic
6570 member functions match targets of type "pointer-to-member
6571 function;" the function type of the pointer to member is used to
6572 select the member function from the set of overloaded member
6573 functions. If a nonstatic member function is selected, the
6574 reference to the overloaded function name is required to have the
6575 form of a pointer to member as described in 5.3.1.
6577 If more than one function is selected, any template functions in
6578 the set are eliminated if the set also contains a non-template
6579 function, and any given template function is eliminated if the
6580 set contains a second template function that is more specialized
6581 than the first according to the partial ordering rules 14.5.5.2.
6582 After such eliminations, if any, there shall remain exactly one
6583 selected function. */
6586 /* We store the matches in a TREE_LIST rooted here. The functions
6587 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6588 interoperability with most_specialized_instantiation. */
6589 tree matches = NULL_TREE;
6591 tree target_fn_type;
6593 /* By the time we get here, we should be seeing only real
6594 pointer-to-member types, not the internal POINTER_TYPE to
6595 METHOD_TYPE representation. */
6596 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
6597 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
6599 gcc_assert (is_overloaded_fn (overload));
6601 /* Check that the TARGET_TYPE is reasonable. */
6602 if (TYPE_PTRFN_P (target_type))
6604 else if (TYPE_PTRMEMFUNC_P (target_type))
6605 /* This is OK, too. */
6607 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6608 /* This is OK, too. This comes from a conversion to reference
6610 target_type = build_reference_type (target_type);
6613 if (flags & tf_error)
6614 error ("cannot resolve overloaded function %qD based on"
6615 " conversion to type %qT",
6616 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6617 return error_mark_node;
6620 /* Non-member functions and static member functions match targets of type
6621 "pointer-to-function" or "reference-to-function." Nonstatic member
6622 functions match targets of type "pointer-to-member-function;" the
6623 function type of the pointer to member is used to select the member
6624 function from the set of overloaded member functions.
6626 So figure out the FUNCTION_TYPE that we want to match against. */
6627 target_fn_type = static_fn_type (target_type);
6629 /* If we can find a non-template function that matches, we can just
6630 use it. There's no point in generating template instantiations
6631 if we're just going to throw them out anyhow. But, of course, we
6632 can only do this when we don't *need* a template function. */
6637 for (fns = overload; fns; fns = OVL_NEXT (fns))
6639 tree fn = OVL_CURRENT (fns);
6641 if (TREE_CODE (fn) == TEMPLATE_DECL)
6642 /* We're not looking for templates just yet. */
6645 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6647 /* We're looking for a non-static member, and this isn't
6648 one, or vice versa. */
6651 /* Ignore functions which haven't been explicitly
6653 if (DECL_ANTICIPATED (fn))
6656 /* See if there's a match. */
6657 if (same_type_p (target_fn_type, static_fn_type (fn)))
6658 matches = tree_cons (fn, NULL_TREE, matches);
6662 /* Now, if we've already got a match (or matches), there's no need
6663 to proceed to the template functions. But, if we don't have a
6664 match we need to look at them, too. */
6667 tree target_arg_types;
6668 tree target_ret_type;
6671 unsigned int nargs, ia;
6674 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6675 target_ret_type = TREE_TYPE (target_fn_type);
6677 nargs = list_length (target_arg_types);
6678 args = XALLOCAVEC (tree, nargs);
6679 for (arg = target_arg_types, ia = 0;
6680 arg != NULL_TREE && arg != void_list_node;
6681 arg = TREE_CHAIN (arg), ++ia)
6682 args[ia] = TREE_VALUE (arg);
6685 for (fns = overload; fns; fns = OVL_NEXT (fns))
6687 tree fn = OVL_CURRENT (fns);
6691 if (TREE_CODE (fn) != TEMPLATE_DECL)
6692 /* We're only looking for templates. */
6695 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6697 /* We're not looking for a non-static member, and this is
6698 one, or vice versa. */
6701 /* Try to do argument deduction. */
6702 targs = make_tree_vec (DECL_NTPARMS (fn));
6703 if (fn_type_unification (fn, explicit_targs, targs, args, nargs,
6704 target_ret_type, DEDUCE_EXACT,
6705 LOOKUP_NORMAL, false))
6706 /* Argument deduction failed. */
6709 /* Instantiate the template. */
6710 instantiation = instantiate_template (fn, targs, flags);
6711 if (instantiation == error_mark_node)
6712 /* Instantiation failed. */
6715 /* See if there's a match. */
6716 if (same_type_p (target_fn_type, static_fn_type (instantiation)))
6717 matches = tree_cons (instantiation, fn, matches);
6720 /* Now, remove all but the most specialized of the matches. */
6723 tree match = most_specialized_instantiation (matches);
6725 if (match != error_mark_node)
6726 matches = tree_cons (TREE_PURPOSE (match),
6732 /* Now we should have exactly one function in MATCHES. */
6733 if (matches == NULL_TREE)
6735 /* There were *no* matches. */
6736 if (flags & tf_error)
6738 error ("no matches converting function %qD to type %q#T",
6739 DECL_NAME (OVL_CURRENT (overload)),
6742 print_candidates (overload);
6744 return error_mark_node;
6746 else if (TREE_CHAIN (matches))
6748 /* There were too many matches. First check if they're all
6749 the same function. */
6752 fn = TREE_PURPOSE (matches);
6753 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6754 if (!decls_match (fn, TREE_PURPOSE (match)))
6759 if (flags & tf_error)
6761 error ("converting overloaded function %qD to type %q#T is ambiguous",
6762 DECL_NAME (OVL_FUNCTION (overload)),
6765 /* Since print_candidates expects the functions in the
6766 TREE_VALUE slot, we flip them here. */
6767 for (match = matches; match; match = TREE_CHAIN (match))
6768 TREE_VALUE (match) = TREE_PURPOSE (match);
6770 print_candidates (matches);
6773 return error_mark_node;
6777 /* Good, exactly one match. Now, convert it to the correct type. */
6778 fn = TREE_PURPOSE (matches);
6780 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6781 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6783 static int explained;
6785 if (!(flags & tf_error))
6786 return error_mark_node;
6788 permerror (input_location, "assuming pointer to member %qD", fn);
6791 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6796 /* If we're doing overload resolution purely for the purpose of
6797 determining conversion sequences, we should not consider the
6798 function used. If this conversion sequence is selected, the
6799 function will be marked as used at this point. */
6800 if (!(flags & tf_conv))
6802 /* Make =delete work with SFINAE. */
6803 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6804 return error_mark_node;
6809 /* We could not check access to member functions when this
6810 expression was originally created since we did not know at that
6811 time to which function the expression referred. */
6812 if (!(flags & tf_no_access_control)
6813 && DECL_FUNCTION_MEMBER_P (fn))
6815 gcc_assert (access_path);
6816 perform_or_defer_access_check (access_path, fn, fn);
6819 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6820 return cp_build_addr_expr (fn, flags);
6823 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6824 will mark the function as addressed, but here we must do it
6826 cxx_mark_addressable (fn);
6832 /* This function will instantiate the type of the expression given in
6833 RHS to match the type of LHSTYPE. If errors exist, then return
6834 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6835 we complain on errors. If we are not complaining, never modify rhs,
6836 as overload resolution wants to try many possible instantiations, in
6837 the hope that at least one will work.
6839 For non-recursive calls, LHSTYPE should be a function, pointer to
6840 function, or a pointer to member function. */
6843 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6845 tsubst_flags_t flags_in = flags;
6846 tree access_path = NULL_TREE;
6848 flags &= ~tf_ptrmem_ok;
6850 if (lhstype == unknown_type_node)
6852 if (flags & tf_error)
6853 error ("not enough type information");
6854 return error_mark_node;
6857 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6859 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6861 if (flag_ms_extensions
6862 && TYPE_PTRMEMFUNC_P (lhstype)
6863 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6864 /* Microsoft allows `A::f' to be resolved to a
6865 pointer-to-member. */
6869 if (flags & tf_error)
6870 error ("cannot convert %qE from type %qT to type %qT",
6871 rhs, TREE_TYPE (rhs), lhstype);
6872 return error_mark_node;
6876 if (BASELINK_P (rhs))
6878 access_path = BASELINK_ACCESS_BINFO (rhs);
6879 rhs = BASELINK_FUNCTIONS (rhs);
6882 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6883 deduce any type information. */
6884 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6886 if (flags & tf_error)
6887 error ("not enough type information");
6888 return error_mark_node;
6891 /* There only a few kinds of expressions that may have a type
6892 dependent on overload resolution. */
6893 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6894 || TREE_CODE (rhs) == COMPONENT_REF
6895 || really_overloaded_fn (rhs)
6896 || (flag_ms_extensions && TREE_CODE (rhs) == FUNCTION_DECL));
6898 /* This should really only be used when attempting to distinguish
6899 what sort of a pointer to function we have. For now, any
6900 arithmetic operation which is not supported on pointers
6901 is rejected as an error. */
6903 switch (TREE_CODE (rhs))
6907 tree member = TREE_OPERAND (rhs, 1);
6909 member = instantiate_type (lhstype, member, flags);
6910 if (member != error_mark_node
6911 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6912 /* Do not lose object's side effects. */
6913 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6914 TREE_OPERAND (rhs, 0), member);
6919 rhs = TREE_OPERAND (rhs, 1);
6920 if (BASELINK_P (rhs))
6921 return instantiate_type (lhstype, rhs, flags_in);
6923 /* This can happen if we are forming a pointer-to-member for a
6925 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6929 case TEMPLATE_ID_EXPR:
6931 tree fns = TREE_OPERAND (rhs, 0);
6932 tree args = TREE_OPERAND (rhs, 1);
6935 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6936 /*template_only=*/true,
6943 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6944 /*template_only=*/false,
6945 /*explicit_targs=*/NULL_TREE,
6950 if (PTRMEM_OK_P (rhs))
6951 flags |= tf_ptrmem_ok;
6953 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6957 return error_mark_node;
6962 return error_mark_node;
6965 /* Return the name of the virtual function pointer field
6966 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6967 this may have to look back through base types to find the
6968 ultimate field name. (For single inheritance, these could
6969 all be the same name. Who knows for multiple inheritance). */
6972 get_vfield_name (tree type)
6974 tree binfo, base_binfo;
6977 for (binfo = TYPE_BINFO (type);
6978 BINFO_N_BASE_BINFOS (binfo);
6981 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6983 if (BINFO_VIRTUAL_P (base_binfo)
6984 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6988 type = BINFO_TYPE (binfo);
6989 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6990 + TYPE_NAME_LENGTH (type) + 2);
6991 sprintf (buf, VFIELD_NAME_FORMAT,
6992 IDENTIFIER_POINTER (constructor_name (type)));
6993 return get_identifier (buf);
6997 print_class_statistics (void)
6999 #ifdef GATHER_STATISTICS
7000 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
7001 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
7004 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
7005 n_vtables, n_vtable_searches);
7006 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
7007 n_vtable_entries, n_vtable_elems);
7012 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
7013 according to [class]:
7014 The class-name is also inserted
7015 into the scope of the class itself. For purposes of access checking,
7016 the inserted class name is treated as if it were a public member name. */
7019 build_self_reference (void)
7021 tree name = constructor_name (current_class_type);
7022 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
7025 DECL_NONLOCAL (value) = 1;
7026 DECL_CONTEXT (value) = current_class_type;
7027 DECL_ARTIFICIAL (value) = 1;
7028 SET_DECL_SELF_REFERENCE_P (value);
7029 set_underlying_type (value);
7031 if (processing_template_decl)
7032 value = push_template_decl (value);
7034 saved_cas = current_access_specifier;
7035 current_access_specifier = access_public_node;
7036 finish_member_declaration (value);
7037 current_access_specifier = saved_cas;
7040 /* Returns 1 if TYPE contains only padding bytes. */
7043 is_empty_class (tree type)
7045 if (type == error_mark_node)
7048 if (! CLASS_TYPE_P (type))
7051 /* In G++ 3.2, whether or not a class was empty was determined by
7052 looking at its size. */
7053 if (abi_version_at_least (2))
7054 return CLASSTYPE_EMPTY_P (type);
7056 return integer_zerop (CLASSTYPE_SIZE (type));
7059 /* Returns true if TYPE contains an empty class. */
7062 contains_empty_class_p (tree type)
7064 if (is_empty_class (type))
7066 if (CLASS_TYPE_P (type))
7073 for (binfo = TYPE_BINFO (type), i = 0;
7074 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7075 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
7077 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
7078 if (TREE_CODE (field) == FIELD_DECL
7079 && !DECL_ARTIFICIAL (field)
7080 && is_empty_class (TREE_TYPE (field)))
7083 else if (TREE_CODE (type) == ARRAY_TYPE)
7084 return contains_empty_class_p (TREE_TYPE (type));
7088 /* Returns true if TYPE contains no actual data, just various
7089 possible combinations of empty classes and possibly a vptr. */
7092 is_really_empty_class (tree type)
7094 if (CLASS_TYPE_P (type))
7101 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
7102 out, but we'd like to be able to check this before then. */
7103 if (COMPLETE_TYPE_P (type) && is_empty_class (type))
7106 for (binfo = TYPE_BINFO (type), i = 0;
7107 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7108 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
7110 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
7111 if (TREE_CODE (field) == FIELD_DECL
7112 && !DECL_ARTIFICIAL (field)
7113 && !is_really_empty_class (TREE_TYPE (field)))
7117 else if (TREE_CODE (type) == ARRAY_TYPE)
7118 return is_really_empty_class (TREE_TYPE (type));
7122 /* Note that NAME was looked up while the current class was being
7123 defined and that the result of that lookup was DECL. */
7126 maybe_note_name_used_in_class (tree name, tree decl)
7128 splay_tree names_used;
7130 /* If we're not defining a class, there's nothing to do. */
7131 if (!(innermost_scope_kind() == sk_class
7132 && TYPE_BEING_DEFINED (current_class_type)
7133 && !LAMBDA_TYPE_P (current_class_type)))
7136 /* If there's already a binding for this NAME, then we don't have
7137 anything to worry about. */
7138 if (lookup_member (current_class_type, name,
7139 /*protect=*/0, /*want_type=*/false))
7142 if (!current_class_stack[current_class_depth - 1].names_used)
7143 current_class_stack[current_class_depth - 1].names_used
7144 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
7145 names_used = current_class_stack[current_class_depth - 1].names_used;
7147 splay_tree_insert (names_used,
7148 (splay_tree_key) name,
7149 (splay_tree_value) decl);
7152 /* Note that NAME was declared (as DECL) in the current class. Check
7153 to see that the declaration is valid. */
7156 note_name_declared_in_class (tree name, tree decl)
7158 splay_tree names_used;
7161 /* Look to see if we ever used this name. */
7163 = current_class_stack[current_class_depth - 1].names_used;
7166 /* The C language allows members to be declared with a type of the same
7167 name, and the C++ standard says this diagnostic is not required. So
7168 allow it in extern "C" blocks unless predantic is specified.
7169 Allow it in all cases if -ms-extensions is specified. */
7170 if ((!pedantic && current_lang_name == lang_name_c)
7171 || flag_ms_extensions)
7173 n = splay_tree_lookup (names_used, (splay_tree_key) name);
7176 /* [basic.scope.class]
7178 A name N used in a class S shall refer to the same declaration
7179 in its context and when re-evaluated in the completed scope of
7181 permerror (input_location, "declaration of %q#D", decl);
7182 permerror (input_location, "changes meaning of %qD from %q+#D",
7183 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
7187 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
7188 Secondary vtables are merged with primary vtables; this function
7189 will return the VAR_DECL for the primary vtable. */
7192 get_vtbl_decl_for_binfo (tree binfo)
7196 decl = BINFO_VTABLE (binfo);
7197 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
7199 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
7200 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
7203 gcc_assert (TREE_CODE (decl) == VAR_DECL);
7208 /* Returns the binfo for the primary base of BINFO. If the resulting
7209 BINFO is a virtual base, and it is inherited elsewhere in the
7210 hierarchy, then the returned binfo might not be the primary base of
7211 BINFO in the complete object. Check BINFO_PRIMARY_P or
7212 BINFO_LOST_PRIMARY_P to be sure. */
7215 get_primary_binfo (tree binfo)
7219 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
7223 return copied_binfo (primary_base, binfo);
7226 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
7229 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
7232 fprintf (stream, "%*s", indent, "");
7236 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
7237 INDENT should be zero when called from the top level; it is
7238 incremented recursively. IGO indicates the next expected BINFO in
7239 inheritance graph ordering. */
7242 dump_class_hierarchy_r (FILE *stream,
7252 indented = maybe_indent_hierarchy (stream, indent, 0);
7253 fprintf (stream, "%s (0x%lx) ",
7254 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
7255 (unsigned long) binfo);
7258 fprintf (stream, "alternative-path\n");
7261 igo = TREE_CHAIN (binfo);
7263 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
7264 tree_low_cst (BINFO_OFFSET (binfo), 0));
7265 if (is_empty_class (BINFO_TYPE (binfo)))
7266 fprintf (stream, " empty");
7267 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
7268 fprintf (stream, " nearly-empty");
7269 if (BINFO_VIRTUAL_P (binfo))
7270 fprintf (stream, " virtual");
7271 fprintf (stream, "\n");
7274 if (BINFO_PRIMARY_P (binfo))
7276 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7277 fprintf (stream, " primary-for %s (0x%lx)",
7278 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
7279 TFF_PLAIN_IDENTIFIER),
7280 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
7282 if (BINFO_LOST_PRIMARY_P (binfo))
7284 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7285 fprintf (stream, " lost-primary");
7288 fprintf (stream, "\n");
7290 if (!(flags & TDF_SLIM))
7294 if (BINFO_SUBVTT_INDEX (binfo))
7296 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7297 fprintf (stream, " subvttidx=%s",
7298 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
7299 TFF_PLAIN_IDENTIFIER));
7301 if (BINFO_VPTR_INDEX (binfo))
7303 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7304 fprintf (stream, " vptridx=%s",
7305 expr_as_string (BINFO_VPTR_INDEX (binfo),
7306 TFF_PLAIN_IDENTIFIER));
7308 if (BINFO_VPTR_FIELD (binfo))
7310 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7311 fprintf (stream, " vbaseoffset=%s",
7312 expr_as_string (BINFO_VPTR_FIELD (binfo),
7313 TFF_PLAIN_IDENTIFIER));
7315 if (BINFO_VTABLE (binfo))
7317 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
7318 fprintf (stream, " vptr=%s",
7319 expr_as_string (BINFO_VTABLE (binfo),
7320 TFF_PLAIN_IDENTIFIER));
7324 fprintf (stream, "\n");
7327 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
7328 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
7333 /* Dump the BINFO hierarchy for T. */
7336 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
7338 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7339 fprintf (stream, " size=%lu align=%lu\n",
7340 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
7341 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
7342 fprintf (stream, " base size=%lu base align=%lu\n",
7343 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
7345 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
7347 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
7348 fprintf (stream, "\n");
7351 /* Debug interface to hierarchy dumping. */
7354 debug_class (tree t)
7356 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
7360 dump_class_hierarchy (tree t)
7363 FILE *stream = dump_begin (TDI_class, &flags);
7367 dump_class_hierarchy_1 (stream, flags, t);
7368 dump_end (TDI_class, stream);
7373 dump_array (FILE * stream, tree decl)
7376 unsigned HOST_WIDE_INT ix;
7378 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
7380 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
7382 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
7383 fprintf (stream, " %s entries",
7384 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
7385 TFF_PLAIN_IDENTIFIER));
7386 fprintf (stream, "\n");
7388 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
7390 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
7391 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
7395 dump_vtable (tree t, tree binfo, tree vtable)
7398 FILE *stream = dump_begin (TDI_class, &flags);
7403 if (!(flags & TDF_SLIM))
7405 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
7407 fprintf (stream, "%s for %s",
7408 ctor_vtbl_p ? "Construction vtable" : "Vtable",
7409 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
7412 if (!BINFO_VIRTUAL_P (binfo))
7413 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
7414 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
7416 fprintf (stream, "\n");
7417 dump_array (stream, vtable);
7418 fprintf (stream, "\n");
7421 dump_end (TDI_class, stream);
7425 dump_vtt (tree t, tree vtt)
7428 FILE *stream = dump_begin (TDI_class, &flags);
7433 if (!(flags & TDF_SLIM))
7435 fprintf (stream, "VTT for %s\n",
7436 type_as_string (t, TFF_PLAIN_IDENTIFIER));
7437 dump_array (stream, vtt);
7438 fprintf (stream, "\n");
7441 dump_end (TDI_class, stream);
7444 /* Dump a function or thunk and its thunkees. */
7447 dump_thunk (FILE *stream, int indent, tree thunk)
7449 static const char spaces[] = " ";
7450 tree name = DECL_NAME (thunk);
7453 fprintf (stream, "%.*s%p %s %s", indent, spaces,
7455 !DECL_THUNK_P (thunk) ? "function"
7456 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
7457 name ? IDENTIFIER_POINTER (name) : "<unset>");
7458 if (DECL_THUNK_P (thunk))
7460 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
7461 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
7463 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
7464 if (!virtual_adjust)
7466 else if (DECL_THIS_THUNK_P (thunk))
7467 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
7468 tree_low_cst (virtual_adjust, 0));
7470 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
7471 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
7472 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
7473 if (THUNK_ALIAS (thunk))
7474 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
7476 fprintf (stream, "\n");
7477 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
7478 dump_thunk (stream, indent + 2, thunks);
7481 /* Dump the thunks for FN. */
7484 debug_thunks (tree fn)
7486 dump_thunk (stderr, 0, fn);
7489 /* Virtual function table initialization. */
7491 /* Create all the necessary vtables for T and its base classes. */
7494 finish_vtbls (tree t)
7497 VEC(constructor_elt,gc) *v = NULL;
7498 tree vtable = BINFO_VTABLE (TYPE_BINFO (t));
7500 /* We lay out the primary and secondary vtables in one contiguous
7501 vtable. The primary vtable is first, followed by the non-virtual
7502 secondary vtables in inheritance graph order. */
7503 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t),
7506 /* Then come the virtual bases, also in inheritance graph order. */
7507 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
7509 if (!BINFO_VIRTUAL_P (vbase))
7511 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), vtable, t, &v);
7514 if (BINFO_VTABLE (TYPE_BINFO (t)))
7515 initialize_vtable (TYPE_BINFO (t), v);
7518 /* Initialize the vtable for BINFO with the INITS. */
7521 initialize_vtable (tree binfo, VEC(constructor_elt,gc) *inits)
7525 layout_vtable_decl (binfo, VEC_length (constructor_elt, inits));
7526 decl = get_vtbl_decl_for_binfo (binfo);
7527 initialize_artificial_var (decl, inits);
7528 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
7531 /* Build the VTT (virtual table table) for T.
7532 A class requires a VTT if it has virtual bases.
7535 1 - primary virtual pointer for complete object T
7536 2 - secondary VTTs for each direct non-virtual base of T which requires a
7538 3 - secondary virtual pointers for each direct or indirect base of T which
7539 has virtual bases or is reachable via a virtual path from T.
7540 4 - secondary VTTs for each direct or indirect virtual base of T.
7542 Secondary VTTs look like complete object VTTs without part 4. */
7550 VEC(constructor_elt,gc) *inits;
7552 /* Build up the initializers for the VTT. */
7554 index = size_zero_node;
7555 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
7557 /* If we didn't need a VTT, we're done. */
7561 /* Figure out the type of the VTT. */
7562 type = build_array_of_n_type (const_ptr_type_node,
7563 VEC_length (constructor_elt, inits));
7565 /* Now, build the VTT object itself. */
7566 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
7567 initialize_artificial_var (vtt, inits);
7568 /* Add the VTT to the vtables list. */
7569 DECL_CHAIN (vtt) = DECL_CHAIN (CLASSTYPE_VTABLES (t));
7570 DECL_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
7575 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7576 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7577 and CHAIN the vtable pointer for this binfo after construction is
7578 complete. VALUE can also be another BINFO, in which case we recurse. */
7581 binfo_ctor_vtable (tree binfo)
7587 vt = BINFO_VTABLE (binfo);
7588 if (TREE_CODE (vt) == TREE_LIST)
7589 vt = TREE_VALUE (vt);
7590 if (TREE_CODE (vt) == TREE_BINFO)
7599 /* Data for secondary VTT initialization. */
7600 typedef struct secondary_vptr_vtt_init_data_s
7602 /* Is this the primary VTT? */
7605 /* Current index into the VTT. */
7608 /* Vector of initializers built up. */
7609 VEC(constructor_elt,gc) *inits;
7611 /* The type being constructed by this secondary VTT. */
7612 tree type_being_constructed;
7613 } secondary_vptr_vtt_init_data;
7615 /* Recursively build the VTT-initializer for BINFO (which is in the
7616 hierarchy dominated by T). INITS points to the end of the initializer
7617 list to date. INDEX is the VTT index where the next element will be
7618 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7619 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7620 for virtual bases of T. When it is not so, we build the constructor
7621 vtables for the BINFO-in-T variant. */
7624 build_vtt_inits (tree binfo, tree t, VEC(constructor_elt,gc) **inits, tree *index)
7629 secondary_vptr_vtt_init_data data;
7630 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7632 /* We only need VTTs for subobjects with virtual bases. */
7633 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7636 /* We need to use a construction vtable if this is not the primary
7640 build_ctor_vtbl_group (binfo, t);
7642 /* Record the offset in the VTT where this sub-VTT can be found. */
7643 BINFO_SUBVTT_INDEX (binfo) = *index;
7646 /* Add the address of the primary vtable for the complete object. */
7647 init = binfo_ctor_vtable (binfo);
7648 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
7651 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7652 BINFO_VPTR_INDEX (binfo) = *index;
7654 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7656 /* Recursively add the secondary VTTs for non-virtual bases. */
7657 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7658 if (!BINFO_VIRTUAL_P (b))
7659 build_vtt_inits (b, t, inits, index);
7661 /* Add secondary virtual pointers for all subobjects of BINFO with
7662 either virtual bases or reachable along a virtual path, except
7663 subobjects that are non-virtual primary bases. */
7664 data.top_level_p = top_level_p;
7665 data.index = *index;
7666 data.inits = *inits;
7667 data.type_being_constructed = BINFO_TYPE (binfo);
7669 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7671 *index = data.index;
7673 /* data.inits might have grown as we added secondary virtual pointers.
7674 Make sure our caller knows about the new vector. */
7675 *inits = data.inits;
7678 /* Add the secondary VTTs for virtual bases in inheritance graph
7680 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7682 if (!BINFO_VIRTUAL_P (b))
7685 build_vtt_inits (b, t, inits, index);
7688 /* Remove the ctor vtables we created. */
7689 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7692 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7693 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7696 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7698 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7700 /* We don't care about bases that don't have vtables. */
7701 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7702 return dfs_skip_bases;
7704 /* We're only interested in proper subobjects of the type being
7706 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7709 /* We're only interested in bases with virtual bases or reachable
7710 via a virtual path from the type being constructed. */
7711 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7712 || binfo_via_virtual (binfo, data->type_being_constructed)))
7713 return dfs_skip_bases;
7715 /* We're not interested in non-virtual primary bases. */
7716 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7719 /* Record the index where this secondary vptr can be found. */
7720 if (data->top_level_p)
7722 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7723 BINFO_VPTR_INDEX (binfo) = data->index;
7725 if (BINFO_VIRTUAL_P (binfo))
7727 /* It's a primary virtual base, and this is not a
7728 construction vtable. Find the base this is primary of in
7729 the inheritance graph, and use that base's vtable
7731 while (BINFO_PRIMARY_P (binfo))
7732 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7736 /* Add the initializer for the secondary vptr itself. */
7737 CONSTRUCTOR_APPEND_ELT (data->inits, NULL_TREE, binfo_ctor_vtable (binfo));
7739 /* Advance the vtt index. */
7740 data->index = size_binop (PLUS_EXPR, data->index,
7741 TYPE_SIZE_UNIT (ptr_type_node));
7746 /* Called from build_vtt_inits via dfs_walk. After building
7747 constructor vtables and generating the sub-vtt from them, we need
7748 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7749 binfo of the base whose sub vtt was generated. */
7752 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7754 tree vtable = BINFO_VTABLE (binfo);
7756 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7757 /* If this class has no vtable, none of its bases do. */
7758 return dfs_skip_bases;
7761 /* This might be a primary base, so have no vtable in this
7765 /* If we scribbled the construction vtable vptr into BINFO, clear it
7767 if (TREE_CODE (vtable) == TREE_LIST
7768 && (TREE_PURPOSE (vtable) == (tree) data))
7769 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7774 /* Build the construction vtable group for BINFO which is in the
7775 hierarchy dominated by T. */
7778 build_ctor_vtbl_group (tree binfo, tree t)
7784 VEC(constructor_elt,gc) *v;
7786 /* See if we've already created this construction vtable group. */
7787 id = mangle_ctor_vtbl_for_type (t, binfo);
7788 if (IDENTIFIER_GLOBAL_VALUE (id))
7791 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7792 /* Build a version of VTBL (with the wrong type) for use in
7793 constructing the addresses of secondary vtables in the
7794 construction vtable group. */
7795 vtbl = build_vtable (t, id, ptr_type_node);
7796 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7799 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7800 binfo, vtbl, t, &v);
7802 /* Add the vtables for each of our virtual bases using the vbase in T
7804 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7806 vbase = TREE_CHAIN (vbase))
7810 if (!BINFO_VIRTUAL_P (vbase))
7812 b = copied_binfo (vbase, binfo);
7814 accumulate_vtbl_inits (b, vbase, binfo, vtbl, t, &v);
7817 /* Figure out the type of the construction vtable. */
7818 type = build_array_of_n_type (vtable_entry_type,
7819 VEC_length (constructor_elt, v));
7821 TREE_TYPE (vtbl) = type;
7822 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7823 layout_decl (vtbl, 0);
7825 /* Initialize the construction vtable. */
7826 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7827 initialize_artificial_var (vtbl, v);
7828 dump_vtable (t, binfo, vtbl);
7831 /* Add the vtbl initializers for BINFO (and its bases other than
7832 non-virtual primaries) to the list of INITS. BINFO is in the
7833 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7834 the constructor the vtbl inits should be accumulated for. (If this
7835 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7836 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7837 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7838 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7839 but are not necessarily the same in terms of layout. */
7842 accumulate_vtbl_inits (tree binfo,
7847 VEC(constructor_elt,gc) **inits)
7851 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7853 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7855 /* If it doesn't have a vptr, we don't do anything. */
7856 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7859 /* If we're building a construction vtable, we're not interested in
7860 subobjects that don't require construction vtables. */
7862 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7863 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7866 /* Build the initializers for the BINFO-in-T vtable. */
7867 dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, vtbl, t, inits);
7869 /* Walk the BINFO and its bases. We walk in preorder so that as we
7870 initialize each vtable we can figure out at what offset the
7871 secondary vtable lies from the primary vtable. We can't use
7872 dfs_walk here because we need to iterate through bases of BINFO
7873 and RTTI_BINFO simultaneously. */
7874 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7876 /* Skip virtual bases. */
7877 if (BINFO_VIRTUAL_P (base_binfo))
7879 accumulate_vtbl_inits (base_binfo,
7880 BINFO_BASE_BINFO (orig_binfo, i),
7881 rtti_binfo, vtbl, t,
7886 /* Called from accumulate_vtbl_inits. Adds the initializers for the
7887 BINFO vtable to L. */
7890 dfs_accumulate_vtbl_inits (tree binfo,
7895 VEC(constructor_elt,gc) **l)
7897 tree vtbl = NULL_TREE;
7898 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7902 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7904 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7905 primary virtual base. If it is not the same primary in
7906 the hierarchy of T, we'll need to generate a ctor vtable
7907 for it, to place at its location in T. If it is the same
7908 primary, we still need a VTT entry for the vtable, but it
7909 should point to the ctor vtable for the base it is a
7910 primary for within the sub-hierarchy of RTTI_BINFO.
7912 There are three possible cases:
7914 1) We are in the same place.
7915 2) We are a primary base within a lost primary virtual base of
7917 3) We are primary to something not a base of RTTI_BINFO. */
7920 tree last = NULL_TREE;
7922 /* First, look through the bases we are primary to for RTTI_BINFO
7923 or a virtual base. */
7925 while (BINFO_PRIMARY_P (b))
7927 b = BINFO_INHERITANCE_CHAIN (b);
7929 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7932 /* If we run out of primary links, keep looking down our
7933 inheritance chain; we might be an indirect primary. */
7934 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7935 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7939 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7940 base B and it is a base of RTTI_BINFO, this is case 2. In
7941 either case, we share our vtable with LAST, i.e. the
7942 derived-most base within B of which we are a primary. */
7944 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7945 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7946 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7947 binfo_ctor_vtable after everything's been set up. */
7950 /* Otherwise, this is case 3 and we get our own. */
7952 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7955 n_inits = VEC_length (constructor_elt, *l);
7962 /* Add the initializer for this vtable. */
7963 build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7964 &non_fn_entries, l);
7966 /* Figure out the position to which the VPTR should point. */
7967 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, orig_vtbl);
7968 index = size_binop (MULT_EXPR,
7969 TYPE_SIZE_UNIT (vtable_entry_type),
7970 size_int (non_fn_entries + n_inits));
7971 vtbl = fold_build_pointer_plus (vtbl, index);
7975 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7976 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7977 straighten this out. */
7978 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7979 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7980 /* Throw away any unneeded intializers. */
7981 VEC_truncate (constructor_elt, *l, n_inits);
7983 /* For an ordinary vtable, set BINFO_VTABLE. */
7984 BINFO_VTABLE (binfo) = vtbl;
7987 static GTY(()) tree abort_fndecl_addr;
7989 /* Construct the initializer for BINFO's virtual function table. BINFO
7990 is part of the hierarchy dominated by T. If we're building a
7991 construction vtable, the ORIG_BINFO is the binfo we should use to
7992 find the actual function pointers to put in the vtable - but they
7993 can be overridden on the path to most-derived in the graph that
7994 ORIG_BINFO belongs. Otherwise,
7995 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7996 BINFO that should be indicated by the RTTI information in the
7997 vtable; it will be a base class of T, rather than T itself, if we
7998 are building a construction vtable.
8000 The value returned is a TREE_LIST suitable for wrapping in a
8001 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
8002 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
8003 number of non-function entries in the vtable.
8005 It might seem that this function should never be called with a
8006 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
8007 base is always subsumed by a derived class vtable. However, when
8008 we are building construction vtables, we do build vtables for
8009 primary bases; we need these while the primary base is being
8013 build_vtbl_initializer (tree binfo,
8017 int* non_fn_entries_p,
8018 VEC(constructor_elt,gc) **inits)
8024 VEC(tree,gc) *vbases;
8027 /* Initialize VID. */
8028 memset (&vid, 0, sizeof (vid));
8031 vid.rtti_binfo = rtti_binfo;
8032 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
8033 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
8034 vid.generate_vcall_entries = true;
8035 /* The first vbase or vcall offset is at index -3 in the vtable. */
8036 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
8038 /* Add entries to the vtable for RTTI. */
8039 build_rtti_vtbl_entries (binfo, &vid);
8041 /* Create an array for keeping track of the functions we've
8042 processed. When we see multiple functions with the same
8043 signature, we share the vcall offsets. */
8044 vid.fns = VEC_alloc (tree, gc, 32);
8045 /* Add the vcall and vbase offset entries. */
8046 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
8048 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
8049 build_vbase_offset_vtbl_entries. */
8050 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
8051 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
8052 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
8054 /* If the target requires padding between data entries, add that now. */
8055 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
8057 int n_entries = VEC_length (constructor_elt, vid.inits);
8059 VEC_safe_grow (constructor_elt, gc, vid.inits,
8060 TARGET_VTABLE_DATA_ENTRY_DISTANCE * n_entries);
8062 /* Move data entries into their new positions and add padding
8063 after the new positions. Iterate backwards so we don't
8064 overwrite entries that we would need to process later. */
8065 for (ix = n_entries - 1;
8066 VEC_iterate (constructor_elt, vid.inits, ix, e);
8070 int new_position = (TARGET_VTABLE_DATA_ENTRY_DISTANCE * ix
8071 + (TARGET_VTABLE_DATA_ENTRY_DISTANCE - 1));
8073 VEC_replace (constructor_elt, vid.inits, new_position, e);
8075 for (j = 1; j < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++j)
8077 constructor_elt *f = VEC_index (constructor_elt, vid.inits,
8079 f->index = NULL_TREE;
8080 f->value = build1 (NOP_EXPR, vtable_entry_type,
8086 if (non_fn_entries_p)
8087 *non_fn_entries_p = VEC_length (constructor_elt, vid.inits);
8089 /* The initializers for virtual functions were built up in reverse
8090 order. Straighten them out and add them to the running list in one
8092 jx = VEC_length (constructor_elt, *inits);
8093 VEC_safe_grow (constructor_elt, gc, *inits,
8094 (jx + VEC_length (constructor_elt, vid.inits)));
8096 for (ix = VEC_length (constructor_elt, vid.inits) - 1;
8097 VEC_iterate (constructor_elt, vid.inits, ix, e);
8099 VEC_replace (constructor_elt, *inits, jx, e);
8101 /* Go through all the ordinary virtual functions, building up
8103 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
8107 tree fn, fn_original;
8108 tree init = NULL_TREE;
8112 if (DECL_THUNK_P (fn))
8114 if (!DECL_NAME (fn))
8116 if (THUNK_ALIAS (fn))
8118 fn = THUNK_ALIAS (fn);
8121 fn_original = THUNK_TARGET (fn);
8124 /* If the only definition of this function signature along our
8125 primary base chain is from a lost primary, this vtable slot will
8126 never be used, so just zero it out. This is important to avoid
8127 requiring extra thunks which cannot be generated with the function.
8129 We first check this in update_vtable_entry_for_fn, so we handle
8130 restored primary bases properly; we also need to do it here so we
8131 zero out unused slots in ctor vtables, rather than filling them
8132 with erroneous values (though harmless, apart from relocation
8134 if (BV_LOST_PRIMARY (v))
8135 init = size_zero_node;
8139 /* Pull the offset for `this', and the function to call, out of
8141 delta = BV_DELTA (v);
8142 vcall_index = BV_VCALL_INDEX (v);
8144 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
8145 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
8147 /* You can't call an abstract virtual function; it's abstract.
8148 So, we replace these functions with __pure_virtual. */
8149 if (DECL_PURE_VIRTUAL_P (fn_original))
8152 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8154 if (abort_fndecl_addr == NULL)
8156 = fold_convert (vfunc_ptr_type_node,
8157 build_fold_addr_expr (fn));
8158 init = abort_fndecl_addr;
8163 if (!integer_zerop (delta) || vcall_index)
8165 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
8166 if (!DECL_NAME (fn))
8169 /* Take the address of the function, considering it to be of an
8170 appropriate generic type. */
8171 if (!TARGET_VTABLE_USES_DESCRIPTORS)
8172 init = fold_convert (vfunc_ptr_type_node,
8173 build_fold_addr_expr (fn));
8177 /* And add it to the chain of initializers. */
8178 if (TARGET_VTABLE_USES_DESCRIPTORS)
8181 if (init == size_zero_node)
8182 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8183 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8185 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
8187 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
8188 fn, build_int_cst (NULL_TREE, i));
8189 TREE_CONSTANT (fdesc) = 1;
8191 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, fdesc);
8195 CONSTRUCTOR_APPEND_ELT (*inits, NULL_TREE, init);
8199 /* Adds to vid->inits the initializers for the vbase and vcall
8200 offsets in BINFO, which is in the hierarchy dominated by T. */
8203 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
8207 /* If this is a derived class, we must first create entries
8208 corresponding to the primary base class. */
8209 b = get_primary_binfo (binfo);
8211 build_vcall_and_vbase_vtbl_entries (b, vid);
8213 /* Add the vbase entries for this base. */
8214 build_vbase_offset_vtbl_entries (binfo, vid);
8215 /* Add the vcall entries for this base. */
8216 build_vcall_offset_vtbl_entries (binfo, vid);
8219 /* Returns the initializers for the vbase offset entries in the vtable
8220 for BINFO (which is part of the class hierarchy dominated by T), in
8221 reverse order. VBASE_OFFSET_INDEX gives the vtable index
8222 where the next vbase offset will go. */
8225 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8229 tree non_primary_binfo;
8231 /* If there are no virtual baseclasses, then there is nothing to
8233 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
8238 /* We might be a primary base class. Go up the inheritance hierarchy
8239 until we find the most derived class of which we are a primary base:
8240 it is the offset of that which we need to use. */
8241 non_primary_binfo = binfo;
8242 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8246 /* If we have reached a virtual base, then it must be a primary
8247 base (possibly multi-level) of vid->binfo, or we wouldn't
8248 have called build_vcall_and_vbase_vtbl_entries for it. But it
8249 might be a lost primary, so just skip down to vid->binfo. */
8250 if (BINFO_VIRTUAL_P (non_primary_binfo))
8252 non_primary_binfo = vid->binfo;
8256 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8257 if (get_primary_binfo (b) != non_primary_binfo)
8259 non_primary_binfo = b;
8262 /* Go through the virtual bases, adding the offsets. */
8263 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
8265 vbase = TREE_CHAIN (vbase))
8270 if (!BINFO_VIRTUAL_P (vbase))
8273 /* Find the instance of this virtual base in the complete
8275 b = copied_binfo (vbase, binfo);
8277 /* If we've already got an offset for this virtual base, we
8278 don't need another one. */
8279 if (BINFO_VTABLE_PATH_MARKED (b))
8281 BINFO_VTABLE_PATH_MARKED (b) = 1;
8283 /* Figure out where we can find this vbase offset. */
8284 delta = size_binop (MULT_EXPR,
8287 TYPE_SIZE_UNIT (vtable_entry_type)));
8288 if (vid->primary_vtbl_p)
8289 BINFO_VPTR_FIELD (b) = delta;
8291 if (binfo != TYPE_BINFO (t))
8292 /* The vbase offset had better be the same. */
8293 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
8295 /* The next vbase will come at a more negative offset. */
8296 vid->index = size_binop (MINUS_EXPR, vid->index,
8297 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8299 /* The initializer is the delta from BINFO to this virtual base.
8300 The vbase offsets go in reverse inheritance-graph order, and
8301 we are walking in inheritance graph order so these end up in
8303 delta = size_diffop_loc (input_location,
8304 BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
8306 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE,
8307 fold_build1_loc (input_location, NOP_EXPR,
8308 vtable_entry_type, delta));
8312 /* Adds the initializers for the vcall offset entries in the vtable
8313 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
8317 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
8319 /* We only need these entries if this base is a virtual base. We
8320 compute the indices -- but do not add to the vtable -- when
8321 building the main vtable for a class. */
8322 if (binfo == TYPE_BINFO (vid->derived)
8323 || (BINFO_VIRTUAL_P (binfo)
8324 /* If BINFO is RTTI_BINFO, then (since BINFO does not
8325 correspond to VID->DERIVED), we are building a primary
8326 construction virtual table. Since this is a primary
8327 virtual table, we do not need the vcall offsets for
8329 && binfo != vid->rtti_binfo))
8331 /* We need a vcall offset for each of the virtual functions in this
8332 vtable. For example:
8334 class A { virtual void f (); };
8335 class B1 : virtual public A { virtual void f (); };
8336 class B2 : virtual public A { virtual void f (); };
8337 class C: public B1, public B2 { virtual void f (); };
8339 A C object has a primary base of B1, which has a primary base of A. A
8340 C also has a secondary base of B2, which no longer has a primary base
8341 of A. So the B2-in-C construction vtable needs a secondary vtable for
8342 A, which will adjust the A* to a B2* to call f. We have no way of
8343 knowing what (or even whether) this offset will be when we define B2,
8344 so we store this "vcall offset" in the A sub-vtable and look it up in
8345 a "virtual thunk" for B2::f.
8347 We need entries for all the functions in our primary vtable and
8348 in our non-virtual bases' secondary vtables. */
8350 /* If we are just computing the vcall indices -- but do not need
8351 the actual entries -- not that. */
8352 if (!BINFO_VIRTUAL_P (binfo))
8353 vid->generate_vcall_entries = false;
8354 /* Now, walk through the non-virtual bases, adding vcall offsets. */
8355 add_vcall_offset_vtbl_entries_r (binfo, vid);
8359 /* Build vcall offsets, starting with those for BINFO. */
8362 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
8368 /* Don't walk into virtual bases -- except, of course, for the
8369 virtual base for which we are building vcall offsets. Any
8370 primary virtual base will have already had its offsets generated
8371 through the recursion in build_vcall_and_vbase_vtbl_entries. */
8372 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
8375 /* If BINFO has a primary base, process it first. */
8376 primary_binfo = get_primary_binfo (binfo);
8378 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
8380 /* Add BINFO itself to the list. */
8381 add_vcall_offset_vtbl_entries_1 (binfo, vid);
8383 /* Scan the non-primary bases of BINFO. */
8384 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
8385 if (base_binfo != primary_binfo)
8386 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
8389 /* Called from build_vcall_offset_vtbl_entries_r. */
8392 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
8394 /* Make entries for the rest of the virtuals. */
8395 if (abi_version_at_least (2))
8399 /* The ABI requires that the methods be processed in declaration
8400 order. G++ 3.2 used the order in the vtable. */
8401 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
8403 orig_fn = DECL_CHAIN (orig_fn))
8404 if (DECL_VINDEX (orig_fn))
8405 add_vcall_offset (orig_fn, binfo, vid);
8409 tree derived_virtuals;
8412 /* If BINFO is a primary base, the most derived class which has
8413 BINFO as a primary base; otherwise, just BINFO. */
8414 tree non_primary_binfo;
8416 /* We might be a primary base class. Go up the inheritance hierarchy
8417 until we find the most derived class of which we are a primary base:
8418 it is the BINFO_VIRTUALS there that we need to consider. */
8419 non_primary_binfo = binfo;
8420 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
8424 /* If we have reached a virtual base, then it must be vid->vbase,
8425 because we ignore other virtual bases in
8426 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
8427 base (possibly multi-level) of vid->binfo, or we wouldn't
8428 have called build_vcall_and_vbase_vtbl_entries for it. But it
8429 might be a lost primary, so just skip down to vid->binfo. */
8430 if (BINFO_VIRTUAL_P (non_primary_binfo))
8432 gcc_assert (non_primary_binfo == vid->vbase);
8433 non_primary_binfo = vid->binfo;
8437 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
8438 if (get_primary_binfo (b) != non_primary_binfo)
8440 non_primary_binfo = b;
8443 if (vid->ctor_vtbl_p)
8444 /* For a ctor vtable we need the equivalent binfo within the hierarchy
8445 where rtti_binfo is the most derived type. */
8447 = original_binfo (non_primary_binfo, vid->rtti_binfo);
8449 for (base_virtuals = BINFO_VIRTUALS (binfo),
8450 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
8451 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
8453 base_virtuals = TREE_CHAIN (base_virtuals),
8454 derived_virtuals = TREE_CHAIN (derived_virtuals),
8455 orig_virtuals = TREE_CHAIN (orig_virtuals))
8459 /* Find the declaration that originally caused this function to
8460 be present in BINFO_TYPE (binfo). */
8461 orig_fn = BV_FN (orig_virtuals);
8463 /* When processing BINFO, we only want to generate vcall slots for
8464 function slots introduced in BINFO. So don't try to generate
8465 one if the function isn't even defined in BINFO. */
8466 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
8469 add_vcall_offset (orig_fn, binfo, vid);
8474 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8477 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
8483 /* If there is already an entry for a function with the same
8484 signature as FN, then we do not need a second vcall offset.
8485 Check the list of functions already present in the derived
8487 FOR_EACH_VEC_ELT (tree, vid->fns, i, derived_entry)
8489 if (same_signature_p (derived_entry, orig_fn)
8490 /* We only use one vcall offset for virtual destructors,
8491 even though there are two virtual table entries. */
8492 || (DECL_DESTRUCTOR_P (derived_entry)
8493 && DECL_DESTRUCTOR_P (orig_fn)))
8497 /* If we are building these vcall offsets as part of building
8498 the vtable for the most derived class, remember the vcall
8500 if (vid->binfo == TYPE_BINFO (vid->derived))
8502 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
8503 CLASSTYPE_VCALL_INDICES (vid->derived),
8505 elt->purpose = orig_fn;
8506 elt->value = vid->index;
8509 /* The next vcall offset will be found at a more negative
8511 vid->index = size_binop (MINUS_EXPR, vid->index,
8512 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
8514 /* Keep track of this function. */
8515 VEC_safe_push (tree, gc, vid->fns, orig_fn);
8517 if (vid->generate_vcall_entries)
8522 /* Find the overriding function. */
8523 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
8524 if (fn == error_mark_node)
8525 vcall_offset = build_zero_cst (vtable_entry_type);
8528 base = TREE_VALUE (fn);
8530 /* The vbase we're working on is a primary base of
8531 vid->binfo. But it might be a lost primary, so its
8532 BINFO_OFFSET might be wrong, so we just use the
8533 BINFO_OFFSET from vid->binfo. */
8534 vcall_offset = size_diffop_loc (input_location,
8535 BINFO_OFFSET (base),
8536 BINFO_OFFSET (vid->binfo));
8537 vcall_offset = fold_build1_loc (input_location,
8538 NOP_EXPR, vtable_entry_type,
8541 /* Add the initializer to the vtable. */
8542 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, vcall_offset);
8546 /* Return vtbl initializers for the RTTI entries corresponding to the
8547 BINFO's vtable. The RTTI entries should indicate the object given
8548 by VID->rtti_binfo. */
8551 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
8559 t = BINFO_TYPE (vid->rtti_binfo);
8561 /* To find the complete object, we will first convert to our most
8562 primary base, and then add the offset in the vtbl to that value. */
8564 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
8565 && !BINFO_LOST_PRIMARY_P (b))
8569 primary_base = get_primary_binfo (b);
8570 gcc_assert (BINFO_PRIMARY_P (primary_base)
8571 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8574 offset = size_diffop_loc (input_location,
8575 BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8577 /* The second entry is the address of the typeinfo object. */
8579 decl = build_address (get_tinfo_decl (t));
8581 decl = integer_zero_node;
8583 /* Convert the declaration to a type that can be stored in the
8585 init = build_nop (vfunc_ptr_type_node, decl);
8586 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8588 /* Add the offset-to-top entry. It comes earlier in the vtable than
8589 the typeinfo entry. Convert the offset to look like a
8590 function pointer, so that we can put it in the vtable. */
8591 init = build_nop (vfunc_ptr_type_node, offset);
8592 CONSTRUCTOR_APPEND_ELT (vid->inits, NULL_TREE, init);
8595 #include "gt-cp-class.h"