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 Free Software Foundation, Inc.
4 Contributed by Michael Tiemann (tiemann@cygnus.com)
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to
20 the Free Software Foundation, 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
24 /* High-level class interface. */
28 #include "coretypes.h"
39 /* The number of nested classes being processed. If we are not in the
40 scope of any class, this is zero. */
42 int current_class_depth;
44 /* In order to deal with nested classes, we keep a stack of classes.
45 The topmost entry is the innermost class, and is the entry at index
46 CURRENT_CLASS_DEPTH */
48 typedef struct class_stack_node {
49 /* The name of the class. */
52 /* The _TYPE node for the class. */
55 /* The access specifier pending for new declarations in the scope of
59 /* If were defining TYPE, the names used in this class. */
60 splay_tree names_used;
61 }* class_stack_node_t;
63 typedef struct vtbl_init_data_s
65 /* The base for which we're building initializers. */
67 /* The type of the most-derived type. */
69 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
70 unless ctor_vtbl_p is true. */
72 /* The negative-index vtable initializers built up so far. These
73 are in order from least negative index to most negative index. */
75 /* The last (i.e., most negative) entry in INITS. */
77 /* The binfo for the virtual base for which we're building
78 vcall offset initializers. */
80 /* The functions in vbase for which we have already provided vcall
83 /* The vtable index of the next vcall or vbase offset. */
85 /* Nonzero if we are building the initializer for the primary
88 /* Nonzero if we are building the initializer for a construction
91 /* True when adding vcall offset entries to the vtable. False when
92 merely computing the indices. */
93 bool generate_vcall_entries;
96 /* The type of a function passed to walk_subobject_offsets. */
97 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
99 /* The stack itself. This is a dynamically resized array. The
100 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
101 static int current_class_stack_size;
102 static class_stack_node_t current_class_stack;
104 /* An array of all local classes present in this translation unit, in
105 declaration order. */
106 varray_type local_classes;
108 static tree get_vfield_name (tree);
109 static void finish_struct_anon (tree);
110 static tree get_vtable_name (tree);
111 static tree get_basefndecls (tree, tree);
112 static int build_primary_vtable (tree, tree);
113 static int build_secondary_vtable (tree);
114 static void finish_vtbls (tree);
115 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
116 static void finish_struct_bits (tree);
117 static int alter_access (tree, tree, tree);
118 static void handle_using_decl (tree, tree);
119 static void check_for_override (tree, tree);
120 static tree dfs_modify_vtables (tree, void *);
121 static tree modify_all_vtables (tree, tree);
122 static void determine_primary_bases (tree);
123 static void finish_struct_methods (tree);
124 static void maybe_warn_about_overly_private_class (tree);
125 static int method_name_cmp (const void *, const void *);
126 static int resort_method_name_cmp (const void *, const void *);
127 static void add_implicitly_declared_members (tree, int, int, int);
128 static tree fixed_type_or_null (tree, int *, int *);
129 static tree resolve_address_of_overloaded_function (tree, tree, tsubst_flags_t,
131 static tree build_simple_base_path (tree expr, tree binfo);
132 static tree build_vtbl_ref_1 (tree, tree);
133 static tree build_vtbl_initializer (tree, tree, tree, tree, int *);
134 static int count_fields (tree);
135 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
136 static void check_bitfield_decl (tree);
137 static void check_field_decl (tree, tree, int *, int *, int *, int *);
138 static void check_field_decls (tree, tree *, int *, int *, int *);
139 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
140 static void build_base_fields (record_layout_info, splay_tree, tree *);
141 static void check_methods (tree);
142 static void remove_zero_width_bit_fields (tree);
143 static void check_bases (tree, int *, int *, int *);
144 static void check_bases_and_members (tree);
145 static tree create_vtable_ptr (tree, tree *);
146 static void include_empty_classes (record_layout_info);
147 static void layout_class_type (tree, tree *);
148 static void fixup_pending_inline (tree);
149 static void fixup_inline_methods (tree);
150 static void propagate_binfo_offsets (tree, tree);
151 static void layout_virtual_bases (record_layout_info, splay_tree);
152 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
153 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
154 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
155 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
156 static void add_vcall_offset (tree, tree, vtbl_init_data *);
157 static void layout_vtable_decl (tree, int);
158 static tree dfs_find_final_overrider (tree, void *);
159 static tree dfs_find_final_overrider_post (tree, void *);
160 static tree dfs_find_final_overrider_q (tree, int, void *);
161 static tree find_final_overrider (tree, tree, tree);
162 static int make_new_vtable (tree, tree);
163 static int maybe_indent_hierarchy (FILE *, int, int);
164 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
165 static void dump_class_hierarchy (tree);
166 static void dump_class_hierarchy_1 (FILE *, int, tree);
167 static void dump_array (FILE *, tree);
168 static void dump_vtable (tree, tree, tree);
169 static void dump_vtt (tree, tree);
170 static void dump_thunk (FILE *, int, tree);
171 static tree build_vtable (tree, tree, tree);
172 static void initialize_vtable (tree, tree);
173 static void layout_nonempty_base_or_field (record_layout_info,
174 tree, tree, splay_tree);
175 static tree end_of_class (tree, int);
176 static bool layout_empty_base (tree, tree, splay_tree);
177 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree);
178 static tree dfs_accumulate_vtbl_inits (tree, tree, tree, tree,
180 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
181 static void build_vcall_and_vbase_vtbl_entries (tree,
183 static void clone_constructors_and_destructors (tree);
184 static tree build_clone (tree, tree);
185 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
186 static void build_ctor_vtbl_group (tree, tree);
187 static void build_vtt (tree);
188 static tree binfo_ctor_vtable (tree);
189 static tree *build_vtt_inits (tree, tree, tree *, tree *);
190 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
191 static tree dfs_ctor_vtable_bases_queue_p (tree, int, void *data);
192 static tree dfs_fixup_binfo_vtbls (tree, void *);
193 static int record_subobject_offset (tree, tree, splay_tree);
194 static int check_subobject_offset (tree, tree, splay_tree);
195 static int walk_subobject_offsets (tree, subobject_offset_fn,
196 tree, splay_tree, tree, int);
197 static void record_subobject_offsets (tree, tree, splay_tree, int);
198 static int layout_conflict_p (tree, tree, splay_tree, int);
199 static int splay_tree_compare_integer_csts (splay_tree_key k1,
201 static void warn_about_ambiguous_bases (tree);
202 static bool type_requires_array_cookie (tree);
203 static bool contains_empty_class_p (tree);
204 static bool base_derived_from (tree, tree);
205 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
206 static tree end_of_base (tree);
207 static tree get_vcall_index (tree, tree);
209 /* Macros for dfs walking during vtt construction. See
210 dfs_ctor_vtable_bases_queue_p, dfs_build_secondary_vptr_vtt_inits
211 and dfs_fixup_binfo_vtbls. */
212 #define VTT_TOP_LEVEL_P(NODE) (TREE_LIST_CHECK (NODE)->common.unsigned_flag)
213 #define VTT_MARKED_BINFO_P(NODE) TREE_USED (NODE)
215 /* Variables shared between class.c and call.c. */
217 #ifdef GATHER_STATISTICS
219 int n_vtable_entries = 0;
220 int n_vtable_searches = 0;
221 int n_vtable_elems = 0;
222 int n_convert_harshness = 0;
223 int n_compute_conversion_costs = 0;
224 int n_inner_fields_searched = 0;
227 /* Convert to or from a base subobject. EXPR is an expression of type
228 `A' or `A*', an expression of type `B' or `B*' is returned. To
229 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
230 the B base instance within A. To convert base A to derived B, CODE
231 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
232 In this latter case, A must not be a morally virtual base of B.
233 NONNULL is true if EXPR is known to be non-NULL (this is only
234 needed when EXPR is of pointer type). CV qualifiers are preserved
238 build_base_path (enum tree_code code,
243 tree v_binfo = NULL_TREE;
244 tree d_binfo = NULL_TREE;
248 tree null_test = NULL;
249 tree ptr_target_type;
251 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
252 bool has_empty = false;
255 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
256 return error_mark_node;
258 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
261 if (is_empty_class (BINFO_TYPE (probe)))
263 if (!v_binfo && BINFO_VIRTUAL_P (probe))
267 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
269 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
271 gcc_assert (code == MINUS_EXPR
272 ? same_type_p (BINFO_TYPE (binfo), probe)
274 ? same_type_p (BINFO_TYPE (d_binfo), probe)
277 if (binfo == d_binfo)
281 if (code == MINUS_EXPR && v_binfo)
283 error ("cannot convert from base `%T' to derived type `%T' via virtual base `%T'",
284 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
285 return error_mark_node;
289 /* This must happen before the call to save_expr. */
290 expr = build_unary_op (ADDR_EXPR, expr, 0);
292 offset = BINFO_OFFSET (binfo);
293 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
295 /* Do we need to look in the vtable for the real offset? */
296 virtual_access = (v_binfo && fixed_type_p <= 0);
298 /* Do we need to check for a null pointer? */
299 if (want_pointer && !nonnull && (virtual_access || !integer_zerop (offset)))
300 null_test = error_mark_node;
302 /* Protect against multiple evaluation if necessary. */
303 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
304 expr = save_expr (expr);
306 /* Now that we've saved expr, build the real null test. */
308 null_test = fold (build2 (NE_EXPR, boolean_type_node,
309 expr, integer_zero_node));
311 /* If this is a simple base reference, express it as a COMPONENT_REF. */
312 if (code == PLUS_EXPR && !virtual_access
313 /* We don't build base fields for empty bases, and they aren't very
314 interesting to the optimizers anyway. */
317 expr = build_indirect_ref (expr, NULL);
318 expr = build_simple_base_path (expr, binfo);
320 expr = build_address (expr);
321 target_type = TREE_TYPE (expr);
327 /* Going via virtual base V_BINFO. We need the static offset
328 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
329 V_BINFO. That offset is an entry in D_BINFO's vtable. */
332 if (fixed_type_p < 0 && in_base_initializer)
334 /* In a base member initializer, we cannot rely on
335 the vtable being set up. We have to use the vtt_parm. */
336 tree derived = BINFO_INHERITANCE_CHAIN (v_binfo);
339 t = TREE_TYPE (TYPE_VFIELD (BINFO_TYPE (derived)));
340 t = build_pointer_type (t);
341 v_offset = convert (t, current_vtt_parm);
342 v_offset = build2 (PLUS_EXPR, t, v_offset,
343 BINFO_VPTR_INDEX (derived));
344 v_offset = build_indirect_ref (v_offset, NULL);
347 v_offset = build_vfield_ref (build_indirect_ref (expr, NULL),
348 TREE_TYPE (TREE_TYPE (expr)));
350 v_offset = build2 (PLUS_EXPR, TREE_TYPE (v_offset),
351 v_offset, BINFO_VPTR_FIELD (v_binfo));
352 v_offset = build1 (NOP_EXPR,
353 build_pointer_type (ptrdiff_type_node),
355 v_offset = build_indirect_ref (v_offset, NULL);
356 TREE_CONSTANT (v_offset) = 1;
357 TREE_INVARIANT (v_offset) = 1;
359 offset = convert_to_integer (ptrdiff_type_node,
361 BINFO_OFFSET (v_binfo)));
363 if (!integer_zerop (offset))
364 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
366 if (fixed_type_p < 0)
367 /* Negative fixed_type_p means this is a constructor or destructor;
368 virtual base layout is fixed in in-charge [cd]tors, but not in
370 offset = build3 (COND_EXPR, ptrdiff_type_node,
371 build2 (EQ_EXPR, boolean_type_node,
372 current_in_charge_parm, integer_zero_node),
374 BINFO_OFFSET (binfo));
379 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
381 target_type = cp_build_qualified_type
382 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
383 ptr_target_type = build_pointer_type (target_type);
385 target_type = ptr_target_type;
387 expr = build1 (NOP_EXPR, ptr_target_type, expr);
389 if (!integer_zerop (offset))
390 expr = build2 (code, ptr_target_type, expr, offset);
395 expr = build_indirect_ref (expr, NULL);
399 expr = fold (build3 (COND_EXPR, target_type, null_test, expr,
400 fold (build1 (NOP_EXPR, target_type,
401 integer_zero_node))));
406 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
407 Perform a derived-to-base conversion by recursively building up a
408 sequence of COMPONENT_REFs to the appropriate base fields. */
411 build_simple_base_path (tree expr, tree binfo)
413 tree type = BINFO_TYPE (binfo);
414 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
417 if (d_binfo == NULL_TREE)
419 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
424 expr = build_simple_base_path (expr, d_binfo);
426 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
427 field; field = TREE_CHAIN (field))
428 /* Is this the base field created by build_base_field? */
429 if (TREE_CODE (field) == FIELD_DECL
430 && DECL_FIELD_IS_BASE (field)
431 && TREE_TYPE (field) == type)
432 return build_class_member_access_expr (expr, field,
435 /* Didn't find the base field?!? */
439 /* Convert OBJECT to the base TYPE. If CHECK_ACCESS is true, an error
440 message is emitted if TYPE is inaccessible. OBJECT is assumed to
444 convert_to_base (tree object, tree type, bool check_access)
448 binfo = lookup_base (TREE_TYPE (object), type,
449 check_access ? ba_check : ba_ignore,
451 if (!binfo || binfo == error_mark_node)
452 return error_mark_node;
454 return build_base_path (PLUS_EXPR, object, binfo, /*nonnull=*/1);
457 /* EXPR is an expression with class type. BASE is a base class (a
458 BINFO) of that class type. Returns EXPR, converted to the BASE
459 type. This function assumes that EXPR is the most derived class;
460 therefore virtual bases can be found at their static offsets. */
463 convert_to_base_statically (tree expr, tree base)
467 expr_type = TREE_TYPE (expr);
468 if (!same_type_p (expr_type, BINFO_TYPE (base)))
472 pointer_type = build_pointer_type (expr_type);
473 expr = build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1);
474 if (!integer_zerop (BINFO_OFFSET (base)))
475 expr = build2 (PLUS_EXPR, pointer_type, expr,
476 build_nop (pointer_type, BINFO_OFFSET (base)));
477 expr = build_nop (build_pointer_type (BINFO_TYPE (base)), expr);
478 expr = build1 (INDIRECT_REF, BINFO_TYPE (base), expr);
486 build_vfield_ref (tree datum, tree type)
488 tree vfield, vcontext;
490 if (datum == error_mark_node)
491 return error_mark_node;
493 if (TREE_CODE (TREE_TYPE (datum)) == REFERENCE_TYPE)
494 datum = convert_from_reference (datum);
496 /* First, convert to the requested type. */
497 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
498 datum = convert_to_base (datum, type, /*check_access=*/false);
500 /* Second, the requested type may not be the owner of its own vptr.
501 If not, convert to the base class that owns it. We cannot use
502 convert_to_base here, because VCONTEXT may appear more than once
503 in the inheritence hierarchy of TYPE, and thus direct conversion
504 between the types may be ambiguous. Following the path back up
505 one step at a time via primary bases avoids the problem. */
506 vfield = TYPE_VFIELD (type);
507 vcontext = DECL_CONTEXT (vfield);
508 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
510 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
511 type = TREE_TYPE (datum);
514 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
517 /* Given an object INSTANCE, return an expression which yields the
518 vtable element corresponding to INDEX. There are many special
519 cases for INSTANCE which we take care of here, mainly to avoid
520 creating extra tree nodes when we don't have to. */
523 build_vtbl_ref_1 (tree instance, tree idx)
526 tree vtbl = NULL_TREE;
528 /* Try to figure out what a reference refers to, and
529 access its virtual function table directly. */
532 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
534 tree basetype = non_reference (TREE_TYPE (instance));
536 if (fixed_type && !cdtorp)
538 tree binfo = lookup_base (fixed_type, basetype,
539 ba_ignore|ba_quiet, NULL);
541 vtbl = unshare_expr (BINFO_VTABLE (binfo));
545 vtbl = build_vfield_ref (instance, basetype);
547 assemble_external (vtbl);
549 aref = build_array_ref (vtbl, idx);
550 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
551 TREE_INVARIANT (aref) = TREE_CONSTANT (aref);
557 build_vtbl_ref (tree instance, tree idx)
559 tree aref = build_vtbl_ref_1 (instance, idx);
564 /* Given a stable object pointer INSTANCE_PTR, return an expression which
565 yields a function pointer corresponding to vtable element INDEX. */
568 build_vfn_ref (tree instance_ptr, tree idx)
572 aref = build_vtbl_ref_1 (build_indirect_ref (instance_ptr, 0), idx);
574 /* When using function descriptors, the address of the
575 vtable entry is treated as a function pointer. */
576 if (TARGET_VTABLE_USES_DESCRIPTORS)
577 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
578 build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1));
580 /* Remember this as a method reference, for later devirtualization. */
581 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
586 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
587 for the given TYPE. */
590 get_vtable_name (tree type)
592 return mangle_vtbl_for_type (type);
595 /* Return an IDENTIFIER_NODE for the name of the virtual table table
599 get_vtt_name (tree type)
601 return mangle_vtt_for_type (type);
604 /* DECL is an entity associated with TYPE, like a virtual table or an
605 implicitly generated constructor. Determine whether or not DECL
606 should have external or internal linkage at the object file
607 level. This routine does not deal with COMDAT linkage and other
608 similar complexities; it simply sets TREE_PUBLIC if it possible for
609 entities in other translation units to contain copies of DECL, in
613 set_linkage_according_to_type (tree type, tree decl)
615 /* If TYPE involves a local class in a function with internal
616 linkage, then DECL should have internal linkage too. Other local
617 classes have no linkage -- but if their containing functions
618 have external linkage, it makes sense for DECL to have external
619 linkage too. That will allow template definitions to be merged,
621 if (no_linkage_check (type, /*relaxed_p=*/true))
623 TREE_PUBLIC (decl) = 0;
624 DECL_INTERFACE_KNOWN (decl) = 1;
627 TREE_PUBLIC (decl) = 1;
630 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
631 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
632 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
635 build_vtable (tree class_type, tree name, tree vtable_type)
639 decl = build_lang_decl (VAR_DECL, name, vtable_type);
640 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
641 now to avoid confusion in mangle_decl. */
642 SET_DECL_ASSEMBLER_NAME (decl, name);
643 DECL_CONTEXT (decl) = class_type;
644 DECL_ARTIFICIAL (decl) = 1;
645 TREE_STATIC (decl) = 1;
646 TREE_READONLY (decl) = 1;
647 DECL_VIRTUAL_P (decl) = 1;
648 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
649 DECL_VTABLE_OR_VTT_P (decl) = 1;
650 /* At one time the vtable info was grabbed 2 words at a time. This
651 fails on sparc unless you have 8-byte alignment. (tiemann) */
652 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
654 set_linkage_according_to_type (class_type, decl);
655 /* The vtable has not been defined -- yet. */
656 DECL_EXTERNAL (decl) = 1;
657 DECL_NOT_REALLY_EXTERN (decl) = 1;
659 if (write_symbols == DWARF2_DEBUG)
660 /* Mark the VAR_DECL node representing the vtable itself as a
661 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
662 is rather important that such things be ignored because any
663 effort to actually generate DWARF for them will run into
664 trouble when/if we encounter code like:
667 struct S { virtual void member (); };
669 because the artificial declaration of the vtable itself (as
670 manufactured by the g++ front end) will say that the vtable is
671 a static member of `S' but only *after* the debug output for
672 the definition of `S' has already been output. This causes
673 grief because the DWARF entry for the definition of the vtable
674 will try to refer back to an earlier *declaration* of the
675 vtable as a static member of `S' and there won't be one. We
676 might be able to arrange to have the "vtable static member"
677 attached to the member list for `S' before the debug info for
678 `S' get written (which would solve the problem) but that would
679 require more intrusive changes to the g++ front end. */
680 DECL_IGNORED_P (decl) = 1;
685 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
686 or even complete. If this does not exist, create it. If COMPLETE is
687 nonzero, then complete the definition of it -- that will render it
688 impossible to actually build the vtable, but is useful to get at those
689 which are known to exist in the runtime. */
692 get_vtable_decl (tree type, int complete)
696 if (CLASSTYPE_VTABLES (type))
697 return CLASSTYPE_VTABLES (type);
699 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
700 CLASSTYPE_VTABLES (type) = decl;
704 DECL_EXTERNAL (decl) = 1;
705 cp_finish_decl (decl, NULL_TREE, NULL_TREE, 0);
711 /* Build the primary virtual function table for TYPE. If BINFO is
712 non-NULL, build the vtable starting with the initial approximation
713 that it is the same as the one which is the head of the association
714 list. Returns a nonzero value if a new vtable is actually
718 build_primary_vtable (tree binfo, tree type)
723 decl = get_vtable_decl (type, /*complete=*/0);
727 if (BINFO_NEW_VTABLE_MARKED (binfo))
728 /* We have already created a vtable for this base, so there's
729 no need to do it again. */
732 virtuals = copy_list (BINFO_VIRTUALS (binfo));
733 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
734 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
735 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
739 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
740 virtuals = NULL_TREE;
743 #ifdef GATHER_STATISTICS
745 n_vtable_elems += list_length (virtuals);
748 /* Initialize the association list for this type, based
749 on our first approximation. */
750 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
751 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
752 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
756 /* Give BINFO a new virtual function table which is initialized
757 with a skeleton-copy of its original initialization. The only
758 entry that changes is the `delta' entry, so we can really
759 share a lot of structure.
761 FOR_TYPE is the most derived type which caused this table to
764 Returns nonzero if we haven't met BINFO before.
766 The order in which vtables are built (by calling this function) for
767 an object must remain the same, otherwise a binary incompatibility
771 build_secondary_vtable (tree binfo)
773 if (BINFO_NEW_VTABLE_MARKED (binfo))
774 /* We already created a vtable for this base. There's no need to
778 /* Remember that we've created a vtable for this BINFO, so that we
779 don't try to do so again. */
780 SET_BINFO_NEW_VTABLE_MARKED (binfo);
782 /* Make fresh virtual list, so we can smash it later. */
783 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
785 /* Secondary vtables are laid out as part of the same structure as
786 the primary vtable. */
787 BINFO_VTABLE (binfo) = NULL_TREE;
791 /* Create a new vtable for BINFO which is the hierarchy dominated by
792 T. Return nonzero if we actually created a new vtable. */
795 make_new_vtable (tree t, tree binfo)
797 if (binfo == TYPE_BINFO (t))
798 /* In this case, it is *type*'s vtable we are modifying. We start
799 with the approximation that its vtable is that of the
800 immediate base class. */
801 return build_primary_vtable (binfo, t);
803 /* This is our very own copy of `basetype' to play with. Later,
804 we will fill in all the virtual functions that override the
805 virtual functions in these base classes which are not defined
806 by the current type. */
807 return build_secondary_vtable (binfo);
810 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
811 (which is in the hierarchy dominated by T) list FNDECL as its
812 BV_FN. DELTA is the required constant adjustment from the `this'
813 pointer where the vtable entry appears to the `this' required when
814 the function is actually called. */
817 modify_vtable_entry (tree t,
827 if (fndecl != BV_FN (v)
828 || !tree_int_cst_equal (delta, BV_DELTA (v)))
830 /* We need a new vtable for BINFO. */
831 if (make_new_vtable (t, binfo))
833 /* If we really did make a new vtable, we also made a copy
834 of the BINFO_VIRTUALS list. Now, we have to find the
835 corresponding entry in that list. */
836 *virtuals = BINFO_VIRTUALS (binfo);
837 while (BV_FN (*virtuals) != BV_FN (v))
838 *virtuals = TREE_CHAIN (*virtuals);
842 BV_DELTA (v) = delta;
843 BV_VCALL_INDEX (v) = NULL_TREE;
849 /* Add method METHOD to class TYPE. */
852 add_method (tree type, tree method)
858 VEC(tree) *method_vec;
860 bool insert_p = false;
863 if (method == error_mark_node)
866 complete_p = COMPLETE_TYPE_P (type);
867 using = (DECL_CONTEXT (method) != type);
868 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
869 && DECL_TEMPLATE_CONV_FN_P (method));
871 method_vec = CLASSTYPE_METHOD_VEC (type);
874 /* Make a new method vector. We start with 8 entries. We must
875 allocate at least two (for constructors and destructors), and
876 we're going to end up with an assignment operator at some
878 method_vec = VEC_alloc (tree, 8);
879 /* Create slots for constructors and destructors. */
880 VEC_quick_push (tree, method_vec, NULL_TREE);
881 VEC_quick_push (tree, method_vec, NULL_TREE);
882 CLASSTYPE_METHOD_VEC (type) = method_vec;
885 /* Constructors and destructors go in special slots. */
886 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
887 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
888 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
890 slot = CLASSTYPE_DESTRUCTOR_SLOT;
891 TYPE_HAS_DESTRUCTOR (type) = 1;
893 if (TYPE_FOR_JAVA (type))
894 error (DECL_ARTIFICIAL (method)
895 ? "Java class '%T' cannot have an implicit non-trivial destructor"
896 : "Java class '%T' cannot have a destructor",
897 DECL_CONTEXT (method));
901 bool conv_p = DECL_CONV_FN_P (method);
905 /* See if we already have an entry with this name. */
906 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
907 VEC_iterate (tree, method_vec, slot, m);
913 if (TREE_CODE (m) == TEMPLATE_DECL
914 && DECL_TEMPLATE_CONV_FN_P (m))
918 if (conv_p && !DECL_CONV_FN_P (m))
920 if (DECL_NAME (m) == DECL_NAME (method))
926 && !DECL_CONV_FN_P (m)
927 && DECL_NAME (m) > DECL_NAME (method))
931 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
933 if (processing_template_decl)
934 /* TYPE is a template class. Don't issue any errors now; wait
935 until instantiation time to complain. */
941 /* Check to see if we've already got this method. */
942 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
944 tree fn = OVL_CURRENT (fns);
949 if (TREE_CODE (fn) != TREE_CODE (method))
952 /* [over.load] Member function declarations with the
953 same name and the same parameter types cannot be
954 overloaded if any of them is a static member
955 function declaration.
957 [namespace.udecl] When a using-declaration brings names
958 from a base class into a derived class scope, member
959 functions in the derived class override and/or hide member
960 functions with the same name and parameter types in a base
961 class (rather than conflicting). */
962 parms1 = TYPE_ARG_TYPES (TREE_TYPE (fn));
963 parms2 = TYPE_ARG_TYPES (TREE_TYPE (method));
965 /* Compare the quals on the 'this' parm. Don't compare
966 the whole types, as used functions are treated as
967 coming from the using class in overload resolution. */
968 if (! DECL_STATIC_FUNCTION_P (fn)
969 && ! DECL_STATIC_FUNCTION_P (method)
970 && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
971 != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
974 /* For templates, the template parms must be identical. */
975 if (TREE_CODE (fn) == TEMPLATE_DECL
976 && !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
977 DECL_TEMPLATE_PARMS (method)))
980 if (! DECL_STATIC_FUNCTION_P (fn))
981 parms1 = TREE_CHAIN (parms1);
982 if (! DECL_STATIC_FUNCTION_P (method))
983 parms2 = TREE_CHAIN (parms2);
985 if (same && compparms (parms1, parms2)
986 && (!DECL_CONV_FN_P (fn)
987 || same_type_p (TREE_TYPE (TREE_TYPE (fn)),
988 TREE_TYPE (TREE_TYPE (method)))))
990 if (using && DECL_CONTEXT (fn) == type)
991 /* Defer to the local function. */
995 cp_error_at ("`%#D' and `%#D' cannot be overloaded",
998 /* We don't call duplicate_decls here to merge
999 the declarations because that will confuse
1000 things if the methods have inline
1001 definitions. In particular, we will crash
1002 while processing the definitions. */
1009 /* Add the new binding. */
1010 overload = build_overload (method, current_fns);
1012 if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1013 push_class_level_binding (DECL_NAME (method), overload);
1017 /* We only expect to add few methods in the COMPLETE_P case, so
1018 just make room for one more method in that case. */
1019 if (VEC_reserve (tree, method_vec, complete_p ? 1 : -1))
1020 CLASSTYPE_METHOD_VEC (type) = method_vec;
1021 if (slot == VEC_length (tree, method_vec))
1022 VEC_quick_push (tree, method_vec, overload);
1024 VEC_quick_insert (tree, method_vec, slot, overload);
1027 /* Replace the current slot. */
1028 VEC_replace (tree, method_vec, slot, overload);
1031 /* Subroutines of finish_struct. */
1033 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1034 legit, otherwise return 0. */
1037 alter_access (tree t, tree fdecl, tree access)
1041 if (!DECL_LANG_SPECIFIC (fdecl))
1042 retrofit_lang_decl (fdecl);
1044 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1046 elem = purpose_member (t, DECL_ACCESS (fdecl));
1049 if (TREE_VALUE (elem) != access)
1051 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1052 cp_error_at ("conflicting access specifications for method `%D', ignored", TREE_TYPE (fdecl));
1054 error ("conflicting access specifications for field `%E', ignored",
1059 /* They're changing the access to the same thing they changed
1060 it to before. That's OK. */
1066 perform_or_defer_access_check (TYPE_BINFO (t), fdecl);
1067 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1073 /* Process the USING_DECL, which is a member of T. */
1076 handle_using_decl (tree using_decl, tree t)
1078 tree ctype = DECL_INITIAL (using_decl);
1079 tree name = DECL_NAME (using_decl);
1081 = TREE_PRIVATE (using_decl) ? access_private_node
1082 : TREE_PROTECTED (using_decl) ? access_protected_node
1083 : access_public_node;
1085 tree flist = NULL_TREE;
1088 if (ctype == error_mark_node)
1091 binfo = lookup_base (t, ctype, ba_any, NULL);
1094 location_t saved_loc = input_location;
1096 input_location = DECL_SOURCE_LOCATION (using_decl);
1097 error_not_base_type (ctype, t);
1098 input_location = saved_loc;
1102 if (constructor_name_p (name, ctype))
1104 cp_error_at ("`%D' names constructor", using_decl);
1107 if (constructor_name_p (name, t))
1109 cp_error_at ("`%D' invalid in `%T'", using_decl, t);
1113 fdecl = lookup_member (binfo, name, 0, false);
1117 cp_error_at ("no members matching `%D' in `%#T'", using_decl, ctype);
1121 if (BASELINK_P (fdecl))
1122 /* Ignore base type this came from. */
1123 fdecl = BASELINK_FUNCTIONS (fdecl);
1125 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1128 if (is_overloaded_fn (old_value))
1129 old_value = OVL_CURRENT (old_value);
1131 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1134 old_value = NULL_TREE;
1137 if (is_overloaded_fn (fdecl))
1142 else if (is_overloaded_fn (old_value))
1145 /* It's OK to use functions from a base when there are functions with
1146 the same name already present in the current class. */;
1149 cp_error_at ("`%D' invalid in `%#T'", using_decl, t);
1150 cp_error_at (" because of local method `%#D' with same name",
1151 OVL_CURRENT (old_value));
1155 else if (!DECL_ARTIFICIAL (old_value))
1157 cp_error_at ("`%D' invalid in `%#T'", using_decl, t);
1158 cp_error_at (" because of local member `%#D' with same name", old_value);
1162 /* Make type T see field decl FDECL with access ACCESS. */
1164 for (; flist; flist = OVL_NEXT (flist))
1166 add_method (t, OVL_CURRENT (flist));
1167 alter_access (t, OVL_CURRENT (flist), access);
1170 alter_access (t, fdecl, access);
1173 /* Run through the base classes of T, updating
1174 CANT_HAVE_DEFAULT_CTOR_P, CANT_HAVE_CONST_CTOR_P, and
1175 NO_CONST_ASN_REF_P. Also set flag bits in T based on properties of
1179 check_bases (tree t,
1180 int* cant_have_default_ctor_p,
1181 int* cant_have_const_ctor_p,
1182 int* no_const_asn_ref_p)
1185 int seen_non_virtual_nearly_empty_base_p;
1189 seen_non_virtual_nearly_empty_base_p = 0;
1191 for (binfo = TYPE_BINFO (t), i = 0;
1192 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1194 tree basetype = TREE_TYPE (base_binfo);
1196 gcc_assert (COMPLETE_TYPE_P (basetype));
1198 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1199 here because the case of virtual functions but non-virtual
1200 dtor is handled in finish_struct_1. */
1201 if (warn_ecpp && ! TYPE_POLYMORPHIC_P (basetype)
1202 && TYPE_HAS_DESTRUCTOR (basetype))
1203 warning ("base class `%#T' has a non-virtual destructor",
1206 /* If the base class doesn't have copy constructors or
1207 assignment operators that take const references, then the
1208 derived class cannot have such a member automatically
1210 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1211 *cant_have_const_ctor_p = 1;
1212 if (TYPE_HAS_ASSIGN_REF (basetype)
1213 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1214 *no_const_asn_ref_p = 1;
1215 /* Similarly, if the base class doesn't have a default
1216 constructor, then the derived class won't have an
1217 automatically generated default constructor. */
1218 if (TYPE_HAS_CONSTRUCTOR (basetype)
1219 && ! TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype))
1221 *cant_have_default_ctor_p = 1;
1222 if (! TYPE_HAS_CONSTRUCTOR (t))
1223 pedwarn ("base `%T' with only non-default constructor in class without a constructor",
1227 if (BINFO_VIRTUAL_P (base_binfo))
1228 /* A virtual base does not effect nearly emptiness. */
1230 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1232 if (seen_non_virtual_nearly_empty_base_p)
1233 /* And if there is more than one nearly empty base, then the
1234 derived class is not nearly empty either. */
1235 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1237 /* Remember we've seen one. */
1238 seen_non_virtual_nearly_empty_base_p = 1;
1240 else if (!is_empty_class (basetype))
1241 /* If the base class is not empty or nearly empty, then this
1242 class cannot be nearly empty. */
1243 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1245 /* A lot of properties from the bases also apply to the derived
1247 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1248 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1249 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1250 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1251 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1252 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1253 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1254 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1255 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1259 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1260 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1261 that have had a nearly-empty virtual primary base stolen by some
1262 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1266 determine_primary_bases (tree t)
1269 tree primary = NULL_TREE;
1270 tree type_binfo = TYPE_BINFO (t);
1273 /* Determine the primary bases of our bases. */
1274 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1275 base_binfo = TREE_CHAIN (base_binfo))
1277 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1279 /* See if we're the non-virtual primary of our inheritance
1281 if (!BINFO_VIRTUAL_P (base_binfo))
1283 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1284 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1287 && BINFO_TYPE (base_binfo) == BINFO_TYPE (parent_primary))
1288 /* We are the primary binfo. */
1289 BINFO_PRIMARY_P (base_binfo) = 1;
1291 /* Determine if we have a virtual primary base, and mark it so.
1293 if (primary && BINFO_VIRTUAL_P (primary))
1295 tree this_primary = copied_binfo (primary, base_binfo);
1297 if (BINFO_PRIMARY_P (this_primary))
1298 /* Someone already claimed this base. */
1299 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1304 BINFO_PRIMARY_P (this_primary) = 1;
1305 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1307 /* A virtual binfo might have been copied from within
1308 another hierarchy. As we're about to use it as a
1309 primary base, make sure the offsets match. */
1310 delta = size_diffop (convert (ssizetype,
1311 BINFO_OFFSET (base_binfo)),
1313 BINFO_OFFSET (this_primary)));
1315 propagate_binfo_offsets (this_primary, delta);
1320 /* First look for a dynamic direct non-virtual base. */
1321 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1323 tree basetype = BINFO_TYPE (base_binfo);
1325 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1327 primary = base_binfo;
1332 /* A "nearly-empty" virtual base class can be the primary base
1333 class, if no non-virtual polymorphic base can be found. Look for
1334 a nearly-empty virtual dynamic base that is not already a primary
1335 base of something in the hierarchy. If there is no such base,
1336 just pick the first nearly-empty virtual base. */
1338 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1339 base_binfo = TREE_CHAIN (base_binfo))
1340 if (BINFO_VIRTUAL_P (base_binfo)
1341 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1343 if (!BINFO_PRIMARY_P (base_binfo))
1345 /* Found one that is not primary. */
1346 primary = base_binfo;
1350 /* Remember the first candidate. */
1351 primary = base_binfo;
1355 /* If we've got a primary base, use it. */
1358 tree basetype = BINFO_TYPE (primary);
1360 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1361 if (BINFO_PRIMARY_P (primary))
1362 /* We are stealing a primary base. */
1363 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1364 BINFO_PRIMARY_P (primary) = 1;
1365 if (BINFO_VIRTUAL_P (primary))
1369 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1370 /* A virtual binfo might have been copied from within
1371 another hierarchy. As we're about to use it as a primary
1372 base, make sure the offsets match. */
1373 delta = size_diffop (ssize_int (0),
1374 convert (ssizetype, BINFO_OFFSET (primary)));
1376 propagate_binfo_offsets (primary, delta);
1379 primary = TYPE_BINFO (basetype);
1381 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1382 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1383 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1387 /* Set memoizing fields and bits of T (and its variants) for later
1391 finish_struct_bits (tree t)
1395 /* Fix up variants (if any). */
1396 for (variants = TYPE_NEXT_VARIANT (t);
1398 variants = TYPE_NEXT_VARIANT (variants))
1400 /* These fields are in the _TYPE part of the node, not in
1401 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1402 TYPE_HAS_CONSTRUCTOR (variants) = TYPE_HAS_CONSTRUCTOR (t);
1403 TYPE_HAS_DESTRUCTOR (variants) = TYPE_HAS_DESTRUCTOR (t);
1404 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1405 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1406 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1408 TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (variants)
1409 = TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (t);
1410 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1411 TYPE_USES_VIRTUAL_BASECLASSES (variants)
1412 = TYPE_USES_VIRTUAL_BASECLASSES (t);
1414 TYPE_BINFO (variants) = TYPE_BINFO (t);
1416 /* Copy whatever these are holding today. */
1417 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1418 TYPE_METHODS (variants) = TYPE_METHODS (t);
1419 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1420 TYPE_SIZE (variants) = TYPE_SIZE (t);
1421 TYPE_SIZE_UNIT (variants) = TYPE_SIZE_UNIT (t);
1424 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1425 /* For a class w/o baseclasses, 'finish_struct' has set
1426 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1427 Similarly for a class whose base classes do not have vtables.
1428 When neither of these is true, we might have removed abstract
1429 virtuals (by providing a definition), added some (by declaring
1430 new ones), or redeclared ones from a base class. We need to
1431 recalculate what's really an abstract virtual at this point (by
1432 looking in the vtables). */
1433 get_pure_virtuals (t);
1435 /* If this type has a copy constructor or a destructor, force its
1436 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1437 nonzero. This will cause it to be passed by invisible reference
1438 and prevent it from being returned in a register. */
1439 if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1442 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1443 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1445 TYPE_MODE (variants) = BLKmode;
1446 TREE_ADDRESSABLE (variants) = 1;
1451 /* Issue warnings about T having private constructors, but no friends,
1454 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1455 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1456 non-private static member functions. */
1459 maybe_warn_about_overly_private_class (tree t)
1461 int has_member_fn = 0;
1462 int has_nonprivate_method = 0;
1465 if (!warn_ctor_dtor_privacy
1466 /* If the class has friends, those entities might create and
1467 access instances, so we should not warn. */
1468 || (CLASSTYPE_FRIEND_CLASSES (t)
1469 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1470 /* We will have warned when the template was declared; there's
1471 no need to warn on every instantiation. */
1472 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1473 /* There's no reason to even consider warning about this
1477 /* We only issue one warning, if more than one applies, because
1478 otherwise, on code like:
1481 // Oops - forgot `public:'
1487 we warn several times about essentially the same problem. */
1489 /* Check to see if all (non-constructor, non-destructor) member
1490 functions are private. (Since there are no friends or
1491 non-private statics, we can't ever call any of the private member
1493 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1494 /* We're not interested in compiler-generated methods; they don't
1495 provide any way to call private members. */
1496 if (!DECL_ARTIFICIAL (fn))
1498 if (!TREE_PRIVATE (fn))
1500 if (DECL_STATIC_FUNCTION_P (fn))
1501 /* A non-private static member function is just like a
1502 friend; it can create and invoke private member
1503 functions, and be accessed without a class
1507 has_nonprivate_method = 1;
1508 /* Keep searching for a static member function. */
1510 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1514 if (!has_nonprivate_method && has_member_fn)
1516 /* There are no non-private methods, and there's at least one
1517 private member function that isn't a constructor or
1518 destructor. (If all the private members are
1519 constructors/destructors we want to use the code below that
1520 issues error messages specifically referring to
1521 constructors/destructors.) */
1523 tree binfo = TYPE_BINFO (t);
1525 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1526 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1528 has_nonprivate_method = 1;
1531 if (!has_nonprivate_method)
1533 warning ("all member functions in class `%T' are private", t);
1538 /* Even if some of the member functions are non-private, the class
1539 won't be useful for much if all the constructors or destructors
1540 are private: such an object can never be created or destroyed. */
1541 if (TYPE_HAS_DESTRUCTOR (t)
1542 && TREE_PRIVATE (CLASSTYPE_DESTRUCTORS (t)))
1544 warning ("`%#T' only defines a private destructor and has no friends",
1549 if (TYPE_HAS_CONSTRUCTOR (t))
1551 int nonprivate_ctor = 0;
1553 /* If a non-template class does not define a copy
1554 constructor, one is defined for it, enabling it to avoid
1555 this warning. For a template class, this does not
1556 happen, and so we would normally get a warning on:
1558 template <class T> class C { private: C(); };
1560 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1561 complete non-template or fully instantiated classes have this
1563 if (!TYPE_HAS_INIT_REF (t))
1564 nonprivate_ctor = 1;
1566 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1568 tree ctor = OVL_CURRENT (fn);
1569 /* Ideally, we wouldn't count copy constructors (or, in
1570 fact, any constructor that takes an argument of the
1571 class type as a parameter) because such things cannot
1572 be used to construct an instance of the class unless
1573 you already have one. But, for now at least, we're
1575 if (! TREE_PRIVATE (ctor))
1577 nonprivate_ctor = 1;
1582 if (nonprivate_ctor == 0)
1584 warning ("`%#T' only defines private constructors and has no friends",
1592 gt_pointer_operator new_value;
1596 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1599 method_name_cmp (const void* m1_p, const void* m2_p)
1601 const tree *const m1 = m1_p;
1602 const tree *const m2 = m2_p;
1604 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1606 if (*m1 == NULL_TREE)
1608 if (*m2 == NULL_TREE)
1610 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1615 /* This routine compares two fields like method_name_cmp but using the
1616 pointer operator in resort_field_decl_data. */
1619 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1621 const tree *const m1 = m1_p;
1622 const tree *const m2 = m2_p;
1623 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1625 if (*m1 == NULL_TREE)
1627 if (*m2 == NULL_TREE)
1630 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1631 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1632 resort_data.new_value (&d1, resort_data.cookie);
1633 resort_data.new_value (&d2, resort_data.cookie);
1640 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1643 resort_type_method_vec (void* obj,
1644 void* orig_obj ATTRIBUTE_UNUSED ,
1645 gt_pointer_operator new_value,
1648 VEC(tree) *method_vec = (VEC(tree) *) obj;
1649 int len = VEC_length (tree, method_vec);
1653 /* The type conversion ops have to live at the front of the vec, so we
1655 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1656 VEC_iterate (tree, method_vec, slot, fn);
1658 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1663 resort_data.new_value = new_value;
1664 resort_data.cookie = cookie;
1665 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1666 resort_method_name_cmp);
1670 /* Warn about duplicate methods in fn_fields. Also compact method
1671 lists so that lookup can be made faster.
1673 Data Structure: List of method lists. The outer list is a
1674 TREE_LIST, whose TREE_PURPOSE field is the field name and the
1675 TREE_VALUE is the DECL_CHAIN of the FUNCTION_DECLs. TREE_CHAIN
1676 links the entire list of methods for TYPE_METHODS. Friends are
1677 chained in the same way as member functions (? TREE_CHAIN or
1678 DECL_CHAIN), but they live in the TREE_TYPE field of the outer
1679 list. That allows them to be quickly deleted, and requires no
1682 Sort methods that are not special (i.e., constructors, destructors,
1683 and type conversion operators) so that we can find them faster in
1687 finish_struct_methods (tree t)
1690 VEC(tree) *method_vec;
1693 method_vec = CLASSTYPE_METHOD_VEC (t);
1697 len = VEC_length (tree, method_vec);
1699 /* First fill in entry 0 with the constructors, entry 1 with destructors,
1700 and the next few with type conversion operators (if any). */
1701 for (fn_fields = TYPE_METHODS (t); fn_fields;
1702 fn_fields = TREE_CHAIN (fn_fields))
1703 /* Clear out this flag. */
1704 DECL_IN_AGGR_P (fn_fields) = 0;
1706 if (TYPE_HAS_DESTRUCTOR (t) && !CLASSTYPE_DESTRUCTORS (t))
1707 /* We thought there was a destructor, but there wasn't. Some
1708 parse errors cause this anomalous situation. */
1709 TYPE_HAS_DESTRUCTOR (t) = 0;
1711 /* Issue warnings about private constructors and such. If there are
1712 no methods, then some public defaults are generated. */
1713 maybe_warn_about_overly_private_class (t);
1715 /* The type conversion ops have to live at the front of the vec, so we
1717 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1718 VEC_iterate (tree, method_vec, slot, fn_fields);
1720 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1723 qsort (VEC_address (tree, method_vec) + slot,
1724 len-slot, sizeof (tree), method_name_cmp);
1727 /* Make BINFO's vtable have N entries, including RTTI entries,
1728 vbase and vcall offsets, etc. Set its type and call the backend
1732 layout_vtable_decl (tree binfo, int n)
1737 atype = build_cplus_array_type (vtable_entry_type,
1738 build_index_type (size_int (n - 1)));
1739 layout_type (atype);
1741 /* We may have to grow the vtable. */
1742 vtable = get_vtbl_decl_for_binfo (binfo);
1743 if (!same_type_p (TREE_TYPE (vtable), atype))
1745 TREE_TYPE (vtable) = atype;
1746 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1747 layout_decl (vtable, 0);
1751 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1752 have the same signature. */
1755 same_signature_p (tree fndecl, tree base_fndecl)
1757 /* One destructor overrides another if they are the same kind of
1759 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1760 && special_function_p (base_fndecl) == special_function_p (fndecl))
1762 /* But a non-destructor never overrides a destructor, nor vice
1763 versa, nor do different kinds of destructors override
1764 one-another. For example, a complete object destructor does not
1765 override a deleting destructor. */
1766 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1769 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1770 || (DECL_CONV_FN_P (fndecl)
1771 && DECL_CONV_FN_P (base_fndecl)
1772 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1773 DECL_CONV_FN_TYPE (base_fndecl))))
1775 tree types, base_types;
1776 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1777 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1778 if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1779 == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1780 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1786 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1790 base_derived_from (tree derived, tree base)
1794 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1796 if (probe == derived)
1798 else if (BINFO_VIRTUAL_P (probe))
1799 /* If we meet a virtual base, we can't follow the inheritance
1800 any more. See if the complete type of DERIVED contains
1801 such a virtual base. */
1802 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1808 typedef struct count_depth_data {
1809 /* The depth of the current subobject, with "1" as the depth of the
1810 most derived object in the hierarchy. */
1812 /* The maximum depth found so far. */
1816 /* Called from find_final_overrider via dfs_walk. */
1819 dfs_depth_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1821 count_depth_data *cd = (count_depth_data *) data;
1822 if (cd->depth > cd->max_depth)
1823 cd->max_depth = cd->depth;
1828 /* Called from find_final_overrider via dfs_walk. */
1831 dfs_depth_q (tree derived, int i, void *data)
1833 count_depth_data *cd = (count_depth_data *) data;
1835 return BINFO_BASE_BINFO (derived, i);
1838 typedef struct find_final_overrider_data_s {
1839 /* The function for which we are trying to find a final overrider. */
1841 /* The base class in which the function was declared. */
1842 tree declaring_base;
1843 /* The most derived class in the hierarchy. */
1844 tree most_derived_type;
1845 /* The candidate overriders. */
1847 /* Each entry in this array is the next-most-derived class for a
1848 virtual base class along the current path. */
1850 /* A pointer one past the top of the VPATH_LIST. */
1852 } find_final_overrider_data;
1854 /* Add the overrider along the current path to FFOD->CANDIDATES.
1855 Returns true if an overrider was found; false otherwise. */
1858 dfs_find_final_overrider_1 (tree binfo,
1860 find_final_overrider_data *ffod)
1864 /* If BINFO is not the most derived type, try a more derived class.
1865 A definition there will overrider a definition here. */
1866 if (!same_type_p (BINFO_TYPE (binfo), ffod->most_derived_type))
1870 if (BINFO_VIRTUAL_P (binfo))
1873 derived = BINFO_INHERITANCE_CHAIN (binfo);
1874 if (dfs_find_final_overrider_1 (derived, vpath, ffod))
1878 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1881 tree *candidate = &ffod->candidates;
1883 /* Remove any candidates overridden by this new function. */
1886 /* If *CANDIDATE overrides METHOD, then METHOD
1887 cannot override anything else on the list. */
1888 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1890 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1891 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1892 *candidate = TREE_CHAIN (*candidate);
1894 candidate = &TREE_CHAIN (*candidate);
1897 /* Add the new function. */
1898 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1905 /* Called from find_final_overrider via dfs_walk. */
1908 dfs_find_final_overrider (tree binfo, void* data)
1910 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1912 if (binfo == ffod->declaring_base)
1913 dfs_find_final_overrider_1 (binfo, ffod->vpath, ffod);
1919 dfs_find_final_overrider_q (tree derived, int ix, void *data)
1921 tree binfo = BINFO_BASE_BINFO (derived, ix);
1922 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1924 if (BINFO_VIRTUAL_P (binfo))
1925 *ffod->vpath++ = derived;
1931 dfs_find_final_overrider_post (tree binfo, void *data)
1933 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1935 if (BINFO_VIRTUAL_P (binfo))
1941 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1942 FN and whose TREE_VALUE is the binfo for the base where the
1943 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1944 DERIVED) is the base object in which FN is declared. */
1947 find_final_overrider (tree derived, tree binfo, tree fn)
1949 find_final_overrider_data ffod;
1950 count_depth_data cd;
1952 /* Getting this right is a little tricky. This is valid:
1954 struct S { virtual void f (); };
1955 struct T { virtual void f (); };
1956 struct U : public S, public T { };
1958 even though calling `f' in `U' is ambiguous. But,
1960 struct R { virtual void f(); };
1961 struct S : virtual public R { virtual void f (); };
1962 struct T : virtual public R { virtual void f (); };
1963 struct U : public S, public T { };
1965 is not -- there's no way to decide whether to put `S::f' or
1966 `T::f' in the vtable for `R'.
1968 The solution is to look at all paths to BINFO. If we find
1969 different overriders along any two, then there is a problem. */
1970 if (DECL_THUNK_P (fn))
1971 fn = THUNK_TARGET (fn);
1973 /* Determine the depth of the hierarchy. */
1976 dfs_walk (derived, dfs_depth_post, dfs_depth_q, &cd);
1979 ffod.declaring_base = binfo;
1980 ffod.most_derived_type = BINFO_TYPE (derived);
1981 ffod.candidates = NULL_TREE;
1982 ffod.vpath_list = (tree *) xcalloc (cd.max_depth, sizeof (tree));
1983 ffod.vpath = ffod.vpath_list;
1985 dfs_walk_real (derived,
1986 dfs_find_final_overrider,
1987 dfs_find_final_overrider_post,
1988 dfs_find_final_overrider_q,
1991 free (ffod.vpath_list);
1993 /* If there was no winner, issue an error message. */
1994 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
1996 error ("no unique final overrider for `%D' in `%T'", fn,
1997 BINFO_TYPE (derived));
1998 return error_mark_node;
2001 return ffod.candidates;
2004 /* Return the index of the vcall offset for FN when TYPE is used as a
2008 get_vcall_index (tree fn, tree type)
2010 VEC (tree_pair_s) *indices = CLASSTYPE_VCALL_INDICES (type);
2014 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
2015 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
2016 || same_signature_p (fn, p->purpose))
2019 /* There should always be an appropriate index. */
2023 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2024 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
2025 corresponding position in the BINFO_VIRTUALS list. */
2028 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2036 tree overrider_fn, overrider_target;
2037 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2038 tree over_return, base_return;
2041 /* Find the nearest primary base (possibly binfo itself) which defines
2042 this function; this is the class the caller will convert to when
2043 calling FN through BINFO. */
2044 for (b = binfo; ; b = get_primary_binfo (b))
2047 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2050 /* The nearest definition is from a lost primary. */
2051 if (BINFO_LOST_PRIMARY_P (b))
2056 /* Find the final overrider. */
2057 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2058 if (overrider == error_mark_node)
2060 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2062 /* Check for adjusting covariant return types. */
2063 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2064 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2066 if (POINTER_TYPE_P (over_return)
2067 && TREE_CODE (over_return) == TREE_CODE (base_return)
2068 && CLASS_TYPE_P (TREE_TYPE (over_return))
2069 && CLASS_TYPE_P (TREE_TYPE (base_return)))
2071 /* If FN is a covariant thunk, we must figure out the adjustment
2072 to the final base FN was converting to. As OVERRIDER_TARGET might
2073 also be converting to the return type of FN, we have to
2074 combine the two conversions here. */
2075 tree fixed_offset, virtual_offset;
2077 if (DECL_THUNK_P (fn))
2079 gcc_assert (DECL_RESULT_THUNK_P (fn));
2080 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2081 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2084 fixed_offset = virtual_offset = NULL_TREE;
2087 /* Find the equivalent binfo within the return type of the
2088 overriding function. We will want the vbase offset from
2090 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2091 TREE_TYPE (over_return));
2092 else if (!same_type_p (TREE_TYPE (over_return),
2093 TREE_TYPE (base_return)))
2095 /* There was no existing virtual thunk (which takes
2100 thunk_binfo = lookup_base (TREE_TYPE (over_return),
2101 TREE_TYPE (base_return),
2102 ba_check | ba_quiet, &kind);
2104 if (thunk_binfo && (kind == bk_via_virtual
2105 || !BINFO_OFFSET_ZEROP (thunk_binfo)))
2107 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2109 if (kind == bk_via_virtual)
2111 /* We convert via virtual base. Find the virtual
2112 base and adjust the fixed offset to be from there. */
2113 while (!BINFO_VIRTUAL_P (thunk_binfo))
2114 thunk_binfo = BINFO_INHERITANCE_CHAIN (thunk_binfo);
2116 virtual_offset = thunk_binfo;
2117 offset = size_diffop
2119 (ssizetype, BINFO_OFFSET (virtual_offset)));
2122 /* There was an existing fixed offset, this must be
2123 from the base just converted to, and the base the
2124 FN was thunking to. */
2125 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2127 fixed_offset = offset;
2131 if (fixed_offset || virtual_offset)
2132 /* Replace the overriding function with a covariant thunk. We
2133 will emit the overriding function in its own slot as
2135 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2136 fixed_offset, virtual_offset);
2139 gcc_assert (!DECL_THUNK_P (fn));
2141 /* Assume that we will produce a thunk that convert all the way to
2142 the final overrider, and not to an intermediate virtual base. */
2143 virtual_base = NULL_TREE;
2145 /* See if we can convert to an intermediate virtual base first, and then
2146 use the vcall offset located there to finish the conversion. */
2147 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2149 /* If we find the final overrider, then we can stop
2151 if (same_type_p (BINFO_TYPE (b),
2152 BINFO_TYPE (TREE_VALUE (overrider))))
2155 /* If we find a virtual base, and we haven't yet found the
2156 overrider, then there is a virtual base between the
2157 declaring base (first_defn) and the final overrider. */
2158 if (BINFO_VIRTUAL_P (b))
2165 if (overrider_fn != overrider_target && !virtual_base)
2167 /* The ABI specifies that a covariant thunk includes a mangling
2168 for a this pointer adjustment. This-adjusting thunks that
2169 override a function from a virtual base have a vcall
2170 adjustment. When the virtual base in question is a primary
2171 virtual base, we know the adjustments are zero, (and in the
2172 non-covariant case, we would not use the thunk).
2173 Unfortunately we didn't notice this could happen, when
2174 designing the ABI and so never mandated that such a covariant
2175 thunk should be emitted. Because we must use the ABI mandated
2176 name, we must continue searching from the binfo where we
2177 found the most recent definition of the function, towards the
2178 primary binfo which first introduced the function into the
2179 vtable. If that enters a virtual base, we must use a vcall
2180 this-adjusting thunk. Bleah! */
2181 tree probe = first_defn;
2183 while ((probe = get_primary_binfo (probe))
2184 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2185 if (BINFO_VIRTUAL_P (probe))
2186 virtual_base = probe;
2189 /* Even if we find a virtual base, the correct delta is
2190 between the overrider and the binfo we're building a vtable
2192 goto virtual_covariant;
2195 /* Compute the constant adjustment to the `this' pointer. The
2196 `this' pointer, when this function is called, will point at BINFO
2197 (or one of its primary bases, which are at the same offset). */
2199 /* The `this' pointer needs to be adjusted from the declaration to
2200 the nearest virtual base. */
2201 delta = size_diffop (convert (ssizetype, BINFO_OFFSET (virtual_base)),
2202 convert (ssizetype, BINFO_OFFSET (first_defn)));
2204 /* If the nearest definition is in a lost primary, we don't need an
2205 entry in our vtable. Except possibly in a constructor vtable,
2206 if we happen to get our primary back. In that case, the offset
2207 will be zero, as it will be a primary base. */
2208 delta = size_zero_node;
2210 /* The `this' pointer needs to be adjusted from pointing to
2211 BINFO to pointing at the base where the final overrider
2214 delta = size_diffop (convert (ssizetype,
2215 BINFO_OFFSET (TREE_VALUE (overrider))),
2216 convert (ssizetype, BINFO_OFFSET (binfo)));
2218 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2221 BV_VCALL_INDEX (*virtuals)
2222 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2224 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2227 /* Called from modify_all_vtables via dfs_walk. */
2230 dfs_modify_vtables (tree binfo, void* data)
2232 tree t = (tree) data;
2234 if (/* There's no need to modify the vtable for a non-virtual
2235 primary base; we're not going to use that vtable anyhow.
2236 We do still need to do this for virtual primary bases, as they
2237 could become non-primary in a construction vtable. */
2238 (!BINFO_PRIMARY_P (binfo) || BINFO_VIRTUAL_P (binfo))
2239 /* Similarly, a base without a vtable needs no modification. */
2240 && TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo))
2241 /* Don't do the primary vtable, if it's new. */
2242 && (BINFO_TYPE (binfo) != t || CLASSTYPE_HAS_PRIMARY_BASE_P (t)))
2248 make_new_vtable (t, binfo);
2250 /* Now, go through each of the virtual functions in the virtual
2251 function table for BINFO. Find the final overrider, and
2252 update the BINFO_VIRTUALS list appropriately. */
2253 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2254 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2256 ix++, virtuals = TREE_CHAIN (virtuals),
2257 old_virtuals = TREE_CHAIN (old_virtuals))
2258 update_vtable_entry_for_fn (t,
2260 BV_FN (old_virtuals),
2264 BINFO_MARKED (binfo) = 1;
2269 /* Update all of the primary and secondary vtables for T. Create new
2270 vtables as required, and initialize their RTTI information. Each
2271 of the functions in VIRTUALS is declared in T and may override a
2272 virtual function from a base class; find and modify the appropriate
2273 entries to point to the overriding functions. Returns a list, in
2274 declaration order, of the virtual functions that are declared in T,
2275 but do not appear in the primary base class vtable, and which
2276 should therefore be appended to the end of the vtable for T. */
2279 modify_all_vtables (tree t, tree virtuals)
2281 tree binfo = TYPE_BINFO (t);
2284 /* Update all of the vtables. */
2285 dfs_walk (binfo, dfs_modify_vtables, unmarkedp, t);
2286 dfs_walk (binfo, dfs_unmark, markedp, t);
2288 /* Add virtual functions not already in our primary vtable. These
2289 will be both those introduced by this class, and those overridden
2290 from secondary bases. It does not include virtuals merely
2291 inherited from secondary bases. */
2292 for (fnsp = &virtuals; *fnsp; )
2294 tree fn = TREE_VALUE (*fnsp);
2296 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2297 || DECL_VINDEX (fn) == error_mark_node)
2299 /* We don't need to adjust the `this' pointer when
2300 calling this function. */
2301 BV_DELTA (*fnsp) = integer_zero_node;
2302 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2304 /* This is a function not already in our vtable. Keep it. */
2305 fnsp = &TREE_CHAIN (*fnsp);
2308 /* We've already got an entry for this function. Skip it. */
2309 *fnsp = TREE_CHAIN (*fnsp);
2315 /* Get the base virtual function declarations in T that have the
2319 get_basefndecls (tree name, tree t)
2322 tree base_fndecls = NULL_TREE;
2323 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2326 /* Find virtual functions in T with the indicated NAME. */
2327 i = lookup_fnfields_1 (t, name);
2329 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2331 methods = OVL_NEXT (methods))
2333 tree method = OVL_CURRENT (methods);
2335 if (TREE_CODE (method) == FUNCTION_DECL
2336 && DECL_VINDEX (method))
2337 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2341 return base_fndecls;
2343 for (i = 0; i < n_baseclasses; i++)
2345 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2346 base_fndecls = chainon (get_basefndecls (name, basetype),
2350 return base_fndecls;
2353 /* If this declaration supersedes the declaration of
2354 a method declared virtual in the base class, then
2355 mark this field as being virtual as well. */
2358 check_for_override (tree decl, tree ctype)
2360 if (TREE_CODE (decl) == TEMPLATE_DECL)
2361 /* In [temp.mem] we have:
2363 A specialization of a member function template does not
2364 override a virtual function from a base class. */
2366 if ((DECL_DESTRUCTOR_P (decl)
2367 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2368 || DECL_CONV_FN_P (decl))
2369 && look_for_overrides (ctype, decl)
2370 && !DECL_STATIC_FUNCTION_P (decl))
2371 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2372 the error_mark_node so that we know it is an overriding
2374 DECL_VINDEX (decl) = decl;
2376 if (DECL_VIRTUAL_P (decl))
2378 if (!DECL_VINDEX (decl))
2379 DECL_VINDEX (decl) = error_mark_node;
2380 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2384 /* Warn about hidden virtual functions that are not overridden in t.
2385 We know that constructors and destructors don't apply. */
2388 warn_hidden (tree t)
2390 VEC(tree) *method_vec = CLASSTYPE_METHOD_VEC (t);
2394 /* We go through each separately named virtual function. */
2395 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2396 VEC_iterate (tree, method_vec, i, fns);
2407 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2408 have the same name. Figure out what name that is. */
2409 name = DECL_NAME (OVL_CURRENT (fns));
2410 /* There are no possibly hidden functions yet. */
2411 base_fndecls = NULL_TREE;
2412 /* Iterate through all of the base classes looking for possibly
2413 hidden functions. */
2414 for (binfo = TYPE_BINFO (t), j = 0;
2415 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2417 tree basetype = BINFO_TYPE (base_binfo);
2418 base_fndecls = chainon (get_basefndecls (name, basetype),
2422 /* If there are no functions to hide, continue. */
2426 /* Remove any overridden functions. */
2427 for (fn = fns; fn; fn = OVL_NEXT (fn))
2429 fndecl = OVL_CURRENT (fn);
2430 if (DECL_VINDEX (fndecl))
2432 tree *prev = &base_fndecls;
2435 /* If the method from the base class has the same
2436 signature as the method from the derived class, it
2437 has been overridden. */
2438 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2439 *prev = TREE_CHAIN (*prev);
2441 prev = &TREE_CHAIN (*prev);
2445 /* Now give a warning for all base functions without overriders,
2446 as they are hidden. */
2447 while (base_fndecls)
2449 /* Here we know it is a hider, and no overrider exists. */
2450 cp_warning_at ("`%D' was hidden", TREE_VALUE (base_fndecls));
2451 cp_warning_at (" by `%D'", fns);
2452 base_fndecls = TREE_CHAIN (base_fndecls);
2457 /* Check for things that are invalid. There are probably plenty of other
2458 things we should check for also. */
2461 finish_struct_anon (tree t)
2465 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2467 if (TREE_STATIC (field))
2469 if (TREE_CODE (field) != FIELD_DECL)
2472 if (DECL_NAME (field) == NULL_TREE
2473 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2475 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2476 for (; elt; elt = TREE_CHAIN (elt))
2478 /* We're generally only interested in entities the user
2479 declared, but we also find nested classes by noticing
2480 the TYPE_DECL that we create implicitly. You're
2481 allowed to put one anonymous union inside another,
2482 though, so we explicitly tolerate that. We use
2483 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2484 we also allow unnamed types used for defining fields. */
2485 if (DECL_ARTIFICIAL (elt)
2486 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2487 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2490 if (TREE_CODE (elt) != FIELD_DECL)
2492 cp_pedwarn_at ("`%#D' invalid; an anonymous union can only have non-static data members",
2497 if (TREE_PRIVATE (elt))
2498 cp_pedwarn_at ("private member `%#D' in anonymous union",
2500 else if (TREE_PROTECTED (elt))
2501 cp_pedwarn_at ("protected member `%#D' in anonymous union",
2504 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2505 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2511 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2512 will be used later during class template instantiation.
2513 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2514 a non-static member data (FIELD_DECL), a member function
2515 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2516 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2517 When FRIEND_P is nonzero, T is either a friend class
2518 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2519 (FUNCTION_DECL, TEMPLATE_DECL). */
2522 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2524 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2525 if (CLASSTYPE_TEMPLATE_INFO (type))
2526 CLASSTYPE_DECL_LIST (type)
2527 = tree_cons (friend_p ? NULL_TREE : type,
2528 t, CLASSTYPE_DECL_LIST (type));
2531 /* Create default constructors, assignment operators, and so forth for
2532 the type indicated by T, if they are needed.
2533 CANT_HAVE_DEFAULT_CTOR, CANT_HAVE_CONST_CTOR, and
2534 CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason, the
2535 class cannot have a default constructor, copy constructor taking a
2536 const reference argument, or an assignment operator taking a const
2537 reference, respectively. If a virtual destructor is created, its
2538 DECL is returned; otherwise the return value is NULL_TREE. */
2541 add_implicitly_declared_members (tree t,
2542 int cant_have_default_ctor,
2543 int cant_have_const_cctor,
2544 int cant_have_const_assignment)
2547 tree implicit_fns = NULL_TREE;
2548 tree virtual_dtor = NULL_TREE;
2552 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) && !TYPE_HAS_DESTRUCTOR (t))
2554 default_fn = implicitly_declare_fn (sfk_destructor, t, /*const_p=*/0);
2555 check_for_override (default_fn, t);
2557 /* If we couldn't make it work, then pretend we didn't need it. */
2558 if (default_fn == void_type_node)
2559 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 0;
2562 TREE_CHAIN (default_fn) = implicit_fns;
2563 implicit_fns = default_fn;
2565 if (DECL_VINDEX (default_fn))
2566 virtual_dtor = default_fn;
2570 /* Any non-implicit destructor is non-trivial. */
2571 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) |= TYPE_HAS_DESTRUCTOR (t);
2573 /* Default constructor. */
2574 if (! TYPE_HAS_CONSTRUCTOR (t) && ! cant_have_default_ctor)
2576 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2577 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2580 /* Copy constructor. */
2581 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2583 TYPE_HAS_INIT_REF (t) = 1;
2584 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2585 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2586 TYPE_HAS_CONSTRUCTOR (t) = 1;
2589 /* If there is no assignment operator, one will be created if and
2590 when it is needed. For now, just record whether or not the type
2591 of the parameter to the assignment operator will be a const or
2592 non-const reference. */
2593 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2595 TYPE_HAS_ASSIGN_REF (t) = 1;
2596 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2597 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2600 /* Now, hook all of the new functions on to TYPE_METHODS,
2601 and add them to the CLASSTYPE_METHOD_VEC. */
2602 for (f = &implicit_fns; *f; f = &TREE_CHAIN (*f))
2605 maybe_add_class_template_decl_list (current_class_type, *f, /*friend_p=*/0);
2607 if (abi_version_at_least (2))
2608 /* G++ 3.2 put the implicit destructor at the *beginning* of the
2609 list, which cause the destructor to be emitted in an incorrect
2610 location in the vtable. */
2611 TYPE_METHODS (t) = chainon (TYPE_METHODS (t), implicit_fns);
2614 if (warn_abi && virtual_dtor)
2615 warning ("vtable layout for class `%T' may not be ABI-compliant "
2616 "and may change in a future version of GCC due to implicit "
2617 "virtual destructor",
2619 *f = TYPE_METHODS (t);
2620 TYPE_METHODS (t) = implicit_fns;
2624 /* Subroutine of finish_struct_1. Recursively count the number of fields
2625 in TYPE, including anonymous union members. */
2628 count_fields (tree fields)
2632 for (x = fields; x; x = TREE_CHAIN (x))
2634 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2635 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2642 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2643 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2646 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2649 for (x = fields; x; x = TREE_CHAIN (x))
2651 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2652 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2654 field_vec->elts[idx++] = x;
2659 /* FIELD is a bit-field. We are finishing the processing for its
2660 enclosing type. Issue any appropriate messages and set appropriate
2664 check_bitfield_decl (tree field)
2666 tree type = TREE_TYPE (field);
2669 /* Detect invalid bit-field type. */
2670 if (DECL_INITIAL (field)
2671 && ! INTEGRAL_TYPE_P (TREE_TYPE (field)))
2673 cp_error_at ("bit-field `%#D' with non-integral type", field);
2674 w = error_mark_node;
2677 /* Detect and ignore out of range field width. */
2678 if (DECL_INITIAL (field))
2680 w = DECL_INITIAL (field);
2682 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2685 /* detect invalid field size. */
2686 if (TREE_CODE (w) == CONST_DECL)
2687 w = DECL_INITIAL (w);
2689 w = decl_constant_value (w);
2691 if (TREE_CODE (w) != INTEGER_CST)
2693 cp_error_at ("bit-field `%D' width not an integer constant",
2695 w = error_mark_node;
2697 else if (tree_int_cst_sgn (w) < 0)
2699 cp_error_at ("negative width in bit-field `%D'", field);
2700 w = error_mark_node;
2702 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2704 cp_error_at ("zero width for bit-field `%D'", field);
2705 w = error_mark_node;
2707 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2708 && TREE_CODE (type) != ENUMERAL_TYPE
2709 && TREE_CODE (type) != BOOLEAN_TYPE)
2710 cp_warning_at ("width of `%D' exceeds its type", field);
2711 else if (TREE_CODE (type) == ENUMERAL_TYPE
2712 && (0 > compare_tree_int (w,
2713 min_precision (TYPE_MIN_VALUE (type),
2714 TYPE_UNSIGNED (type)))
2715 || 0 > compare_tree_int (w,
2717 (TYPE_MAX_VALUE (type),
2718 TYPE_UNSIGNED (type)))))
2719 cp_warning_at ("`%D' is too small to hold all values of `%#T'",
2723 /* Remove the bit-field width indicator so that the rest of the
2724 compiler does not treat that value as an initializer. */
2725 DECL_INITIAL (field) = NULL_TREE;
2727 if (w != error_mark_node)
2729 DECL_SIZE (field) = convert (bitsizetype, w);
2730 DECL_BIT_FIELD (field) = 1;
2734 /* Non-bit-fields are aligned for their type. */
2735 DECL_BIT_FIELD (field) = 0;
2736 CLEAR_DECL_C_BIT_FIELD (field);
2740 /* FIELD is a non bit-field. We are finishing the processing for its
2741 enclosing type T. Issue any appropriate messages and set appropriate
2745 check_field_decl (tree field,
2747 int* cant_have_const_ctor,
2748 int* cant_have_default_ctor,
2749 int* no_const_asn_ref,
2750 int* any_default_members)
2752 tree type = strip_array_types (TREE_TYPE (field));
2754 /* An anonymous union cannot contain any fields which would change
2755 the settings of CANT_HAVE_CONST_CTOR and friends. */
2756 if (ANON_UNION_TYPE_P (type))
2758 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2759 structs. So, we recurse through their fields here. */
2760 else if (ANON_AGGR_TYPE_P (type))
2764 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2765 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2766 check_field_decl (fields, t, cant_have_const_ctor,
2767 cant_have_default_ctor, no_const_asn_ref,
2768 any_default_members);
2770 /* Check members with class type for constructors, destructors,
2772 else if (CLASS_TYPE_P (type))
2774 /* Never let anything with uninheritable virtuals
2775 make it through without complaint. */
2776 abstract_virtuals_error (field, type);
2778 if (TREE_CODE (t) == UNION_TYPE)
2780 if (TYPE_NEEDS_CONSTRUCTING (type))
2781 cp_error_at ("member `%#D' with constructor not allowed in union",
2783 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2784 cp_error_at ("member `%#D' with destructor not allowed in union",
2786 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2787 cp_error_at ("member `%#D' with copy assignment operator not allowed in union",
2792 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2793 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2794 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2795 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2796 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2799 if (!TYPE_HAS_CONST_INIT_REF (type))
2800 *cant_have_const_ctor = 1;
2802 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2803 *no_const_asn_ref = 1;
2805 if (TYPE_HAS_CONSTRUCTOR (type)
2806 && ! TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
2807 *cant_have_default_ctor = 1;
2809 if (DECL_INITIAL (field) != NULL_TREE)
2811 /* `build_class_init_list' does not recognize
2813 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2814 error ("multiple fields in union `%T' initialized", t);
2815 *any_default_members = 1;
2819 /* Check the data members (both static and non-static), class-scoped
2820 typedefs, etc., appearing in the declaration of T. Issue
2821 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2822 declaration order) of access declarations; each TREE_VALUE in this
2823 list is a USING_DECL.
2825 In addition, set the following flags:
2828 The class is empty, i.e., contains no non-static data members.
2830 CANT_HAVE_DEFAULT_CTOR_P
2831 This class cannot have an implicitly generated default
2834 CANT_HAVE_CONST_CTOR_P
2835 This class cannot have an implicitly generated copy constructor
2836 taking a const reference.
2838 CANT_HAVE_CONST_ASN_REF
2839 This class cannot have an implicitly generated assignment
2840 operator taking a const reference.
2842 All of these flags should be initialized before calling this
2845 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2846 fields can be added by adding to this chain. */
2849 check_field_decls (tree t, tree *access_decls,
2850 int *cant_have_default_ctor_p,
2851 int *cant_have_const_ctor_p,
2852 int *no_const_asn_ref_p)
2857 int any_default_members;
2859 /* Assume there are no access declarations. */
2860 *access_decls = NULL_TREE;
2861 /* Assume this class has no pointer members. */
2862 has_pointers = false;
2863 /* Assume none of the members of this class have default
2865 any_default_members = 0;
2867 for (field = &TYPE_FIELDS (t); *field; field = next)
2870 tree type = TREE_TYPE (x);
2872 next = &TREE_CHAIN (x);
2874 if (TREE_CODE (x) == FIELD_DECL)
2876 if (TYPE_PACKED (t))
2878 if (!pod_type_p (TREE_TYPE (x)) && !TYPE_PACKED (TREE_TYPE (x)))
2880 ("ignoring packed attribute on unpacked non-POD field `%#D'",
2883 DECL_PACKED (x) = 1;
2886 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
2887 /* We don't treat zero-width bitfields as making a class
2894 /* The class is non-empty. */
2895 CLASSTYPE_EMPTY_P (t) = 0;
2896 /* The class is not even nearly empty. */
2897 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
2898 /* If one of the data members contains an empty class,
2900 element_type = strip_array_types (type);
2901 if (CLASS_TYPE_P (element_type)
2902 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
2903 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
2907 if (TREE_CODE (x) == USING_DECL)
2909 /* Prune the access declaration from the list of fields. */
2910 *field = TREE_CHAIN (x);
2912 /* Save the access declarations for our caller. */
2913 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2915 /* Since we've reset *FIELD there's no reason to skip to the
2921 if (TREE_CODE (x) == TYPE_DECL
2922 || TREE_CODE (x) == TEMPLATE_DECL)
2925 /* If we've gotten this far, it's a data member, possibly static,
2926 or an enumerator. */
2927 DECL_CONTEXT (x) = t;
2929 /* When this goes into scope, it will be a non-local reference. */
2930 DECL_NONLOCAL (x) = 1;
2932 if (TREE_CODE (t) == UNION_TYPE)
2936 If a union contains a static data member, or a member of
2937 reference type, the program is ill-formed. */
2938 if (TREE_CODE (x) == VAR_DECL)
2940 cp_error_at ("`%D' may not be static because it is a member of a union", x);
2943 if (TREE_CODE (type) == REFERENCE_TYPE)
2945 cp_error_at ("`%D' may not have reference type `%T' because it is a member of a union",
2951 /* ``A local class cannot have static data members.'' ARM 9.4 */
2952 if (current_function_decl && TREE_STATIC (x))
2953 cp_error_at ("field `%D' in local class cannot be static", x);
2955 /* Perform error checking that did not get done in
2957 if (TREE_CODE (type) == FUNCTION_TYPE)
2959 cp_error_at ("field `%D' invalidly declared function type",
2961 type = build_pointer_type (type);
2962 TREE_TYPE (x) = type;
2964 else if (TREE_CODE (type) == METHOD_TYPE)
2966 cp_error_at ("field `%D' invalidly declared method type", x);
2967 type = build_pointer_type (type);
2968 TREE_TYPE (x) = type;
2971 if (type == error_mark_node)
2974 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
2977 /* Now it can only be a FIELD_DECL. */
2979 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
2980 CLASSTYPE_NON_AGGREGATE (t) = 1;
2982 /* If this is of reference type, check if it needs an init.
2983 Also do a little ANSI jig if necessary. */
2984 if (TREE_CODE (type) == REFERENCE_TYPE)
2986 CLASSTYPE_NON_POD_P (t) = 1;
2987 if (DECL_INITIAL (x) == NULL_TREE)
2988 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2990 /* ARM $12.6.2: [A member initializer list] (or, for an
2991 aggregate, initialization by a brace-enclosed list) is the
2992 only way to initialize nonstatic const and reference
2994 *cant_have_default_ctor_p = 1;
2995 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2997 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
2999 cp_warning_at ("non-static reference `%#D' in class without a constructor", x);
3002 type = strip_array_types (type);
3004 /* This is used by -Weffc++ (see below). Warn only for pointers
3005 to members which might hold dynamic memory. So do not warn
3006 for pointers to functions or pointers to members. */
3007 if (TYPE_PTR_P (type)
3008 && !TYPE_PTRFN_P (type)
3009 && !TYPE_PTR_TO_MEMBER_P (type))
3010 has_pointers = true;
3012 if (CLASS_TYPE_P (type))
3014 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3015 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3016 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3017 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3020 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3021 CLASSTYPE_HAS_MUTABLE (t) = 1;
3023 if (! pod_type_p (type))
3024 /* DR 148 now allows pointers to members (which are POD themselves),
3025 to be allowed in POD structs. */
3026 CLASSTYPE_NON_POD_P (t) = 1;
3028 if (! zero_init_p (type))
3029 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3031 /* If any field is const, the structure type is pseudo-const. */
3032 if (CP_TYPE_CONST_P (type))
3034 C_TYPE_FIELDS_READONLY (t) = 1;
3035 if (DECL_INITIAL (x) == NULL_TREE)
3036 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3038 /* ARM $12.6.2: [A member initializer list] (or, for an
3039 aggregate, initialization by a brace-enclosed list) is the
3040 only way to initialize nonstatic const and reference
3042 *cant_have_default_ctor_p = 1;
3043 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3045 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
3047 cp_warning_at ("non-static const member `%#D' in class without a constructor", x);
3049 /* A field that is pseudo-const makes the structure likewise. */
3050 else if (CLASS_TYPE_P (type))
3052 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3053 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3054 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3055 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3058 /* Core issue 80: A nonstatic data member is required to have a
3059 different name from the class iff the class has a
3060 user-defined constructor. */
3061 if (constructor_name_p (DECL_NAME (x), t) && TYPE_HAS_CONSTRUCTOR (t))
3062 cp_pedwarn_at ("field `%#D' with same name as class", x);
3064 /* We set DECL_C_BIT_FIELD in grokbitfield.
3065 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3066 if (DECL_C_BIT_FIELD (x))
3067 check_bitfield_decl (x);
3069 check_field_decl (x, t,
3070 cant_have_const_ctor_p,
3071 cant_have_default_ctor_p,
3073 &any_default_members);
3076 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3077 it should also define a copy constructor and an assignment operator to
3078 implement the correct copy semantic (deep vs shallow, etc.). As it is
3079 not feasible to check whether the constructors do allocate dynamic memory
3080 and store it within members, we approximate the warning like this:
3082 -- Warn only if there are members which are pointers
3083 -- Warn only if there is a non-trivial constructor (otherwise,
3084 there cannot be memory allocated).
3085 -- Warn only if there is a non-trivial destructor. We assume that the
3086 user at least implemented the cleanup correctly, and a destructor
3087 is needed to free dynamic memory.
3089 This seems enough for practical purposes. */
3092 && TYPE_HAS_CONSTRUCTOR (t)
3093 && TYPE_HAS_DESTRUCTOR (t)
3094 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3096 warning ("`%#T' has pointer data members", t);
3098 if (! TYPE_HAS_INIT_REF (t))
3100 warning (" but does not override `%T(const %T&)'", t, t);
3101 if (! TYPE_HAS_ASSIGN_REF (t))
3102 warning (" or `operator=(const %T&)'", t);
3104 else if (! TYPE_HAS_ASSIGN_REF (t))
3105 warning (" but does not override `operator=(const %T&)'", t);
3109 /* Check anonymous struct/anonymous union fields. */
3110 finish_struct_anon (t);
3112 /* We've built up the list of access declarations in reverse order.
3114 *access_decls = nreverse (*access_decls);
3117 /* If TYPE is an empty class type, records its OFFSET in the table of
3121 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3125 if (!is_empty_class (type))
3128 /* Record the location of this empty object in OFFSETS. */
3129 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3131 n = splay_tree_insert (offsets,
3132 (splay_tree_key) offset,
3133 (splay_tree_value) NULL_TREE);
3134 n->value = ((splay_tree_value)
3135 tree_cons (NULL_TREE,
3142 /* Returns nonzero if TYPE is an empty class type and there is
3143 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3146 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3151 if (!is_empty_class (type))
3154 /* Record the location of this empty object in OFFSETS. */
3155 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3159 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3160 if (same_type_p (TREE_VALUE (t), type))
3166 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3167 F for every subobject, passing it the type, offset, and table of
3168 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3171 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3172 than MAX_OFFSET will not be walked.
3174 If F returns a nonzero value, the traversal ceases, and that value
3175 is returned. Otherwise, returns zero. */
3178 walk_subobject_offsets (tree type,
3179 subobject_offset_fn f,
3186 tree type_binfo = NULL_TREE;
3188 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3190 if (max_offset && INT_CST_LT (max_offset, offset))
3195 if (abi_version_at_least (2))
3197 type = BINFO_TYPE (type);
3200 if (CLASS_TYPE_P (type))
3206 /* Avoid recursing into objects that are not interesting. */
3207 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3210 /* Record the location of TYPE. */
3211 r = (*f) (type, offset, offsets);
3215 /* Iterate through the direct base classes of TYPE. */
3217 type_binfo = TYPE_BINFO (type);
3218 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3222 if (abi_version_at_least (2)
3223 && BINFO_VIRTUAL_P (binfo))
3227 && BINFO_VIRTUAL_P (binfo)
3228 && !BINFO_PRIMARY_P (binfo))
3231 if (!abi_version_at_least (2))
3232 binfo_offset = size_binop (PLUS_EXPR,
3234 BINFO_OFFSET (binfo));
3238 /* We cannot rely on BINFO_OFFSET being set for the base
3239 class yet, but the offsets for direct non-virtual
3240 bases can be calculated by going back to the TYPE. */
3241 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3242 binfo_offset = size_binop (PLUS_EXPR,
3244 BINFO_OFFSET (orig_binfo));
3247 r = walk_subobject_offsets (binfo,
3252 (abi_version_at_least (2)
3253 ? /*vbases_p=*/0 : vbases_p));
3258 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3263 /* Iterate through the virtual base classes of TYPE. In G++
3264 3.2, we included virtual bases in the direct base class
3265 loop above, which results in incorrect results; the
3266 correct offsets for virtual bases are only known when
3267 working with the most derived type. */
3269 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3270 VEC_iterate (tree, vbases, ix, binfo); ix++)
3272 r = walk_subobject_offsets (binfo,
3274 size_binop (PLUS_EXPR,
3276 BINFO_OFFSET (binfo)),
3285 /* We still have to walk the primary base, if it is
3286 virtual. (If it is non-virtual, then it was walked
3288 tree vbase = get_primary_binfo (type_binfo);
3290 if (vbase && BINFO_VIRTUAL_P (vbase)
3291 && BINFO_PRIMARY_P (vbase)
3292 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3294 r = (walk_subobject_offsets
3296 offsets, max_offset, /*vbases_p=*/0));
3303 /* Iterate through the fields of TYPE. */
3304 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3305 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3309 if (abi_version_at_least (2))
3310 field_offset = byte_position (field);
3312 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3313 field_offset = DECL_FIELD_OFFSET (field);
3315 r = walk_subobject_offsets (TREE_TYPE (field),
3317 size_binop (PLUS_EXPR,
3327 else if (TREE_CODE (type) == ARRAY_TYPE)
3329 tree element_type = strip_array_types (type);
3330 tree domain = TYPE_DOMAIN (type);
3333 /* Avoid recursing into objects that are not interesting. */
3334 if (!CLASS_TYPE_P (element_type)
3335 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3338 /* Step through each of the elements in the array. */
3339 for (index = size_zero_node;
3340 /* G++ 3.2 had an off-by-one error here. */
3341 (abi_version_at_least (2)
3342 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3343 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3344 index = size_binop (PLUS_EXPR, index, size_one_node))
3346 r = walk_subobject_offsets (TREE_TYPE (type),
3354 offset = size_binop (PLUS_EXPR, offset,
3355 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3356 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3357 there's no point in iterating through the remaining
3358 elements of the array. */
3359 if (max_offset && INT_CST_LT (max_offset, offset))
3367 /* Record all of the empty subobjects of TYPE (located at OFFSET) in
3368 OFFSETS. If VBASES_P is nonzero, virtual bases of TYPE are
3372 record_subobject_offsets (tree type,
3377 walk_subobject_offsets (type, record_subobject_offset, offset,
3378 offsets, /*max_offset=*/NULL_TREE, vbases_p);
3381 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3382 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3383 virtual bases of TYPE are examined. */
3386 layout_conflict_p (tree type,
3391 splay_tree_node max_node;
3393 /* Get the node in OFFSETS that indicates the maximum offset where
3394 an empty subobject is located. */
3395 max_node = splay_tree_max (offsets);
3396 /* If there aren't any empty subobjects, then there's no point in
3397 performing this check. */
3401 return walk_subobject_offsets (type, check_subobject_offset, offset,
3402 offsets, (tree) (max_node->key),
3406 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3407 non-static data member of the type indicated by RLI. BINFO is the
3408 binfo corresponding to the base subobject, OFFSETS maps offsets to
3409 types already located at those offsets. This function determines
3410 the position of the DECL. */
3413 layout_nonempty_base_or_field (record_layout_info rli,
3418 tree offset = NULL_TREE;
3424 /* For the purposes of determining layout conflicts, we want to
3425 use the class type of BINFO; TREE_TYPE (DECL) will be the
3426 CLASSTYPE_AS_BASE version, which does not contain entries for
3427 zero-sized bases. */
3428 type = TREE_TYPE (binfo);
3433 type = TREE_TYPE (decl);
3437 /* Try to place the field. It may take more than one try if we have
3438 a hard time placing the field without putting two objects of the
3439 same type at the same address. */
3442 struct record_layout_info_s old_rli = *rli;
3444 /* Place this field. */
3445 place_field (rli, decl);
3446 offset = byte_position (decl);
3448 /* We have to check to see whether or not there is already
3449 something of the same type at the offset we're about to use.
3450 For example, consider:
3453 struct T : public S { int i; };
3454 struct U : public S, public T {};
3456 Here, we put S at offset zero in U. Then, we can't put T at
3457 offset zero -- its S component would be at the same address
3458 as the S we already allocated. So, we have to skip ahead.
3459 Since all data members, including those whose type is an
3460 empty class, have nonzero size, any overlap can happen only
3461 with a direct or indirect base-class -- it can't happen with
3463 /* In a union, overlap is permitted; all members are placed at
3465 if (TREE_CODE (rli->t) == UNION_TYPE)
3467 /* G++ 3.2 did not check for overlaps when placing a non-empty
3469 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3471 if (layout_conflict_p (field_p ? type : binfo, offset,
3474 /* Strip off the size allocated to this field. That puts us
3475 at the first place we could have put the field with
3476 proper alignment. */
3479 /* Bump up by the alignment required for the type. */
3481 = size_binop (PLUS_EXPR, rli->bitpos,
3483 ? CLASSTYPE_ALIGN (type)
3484 : TYPE_ALIGN (type)));
3485 normalize_rli (rli);
3488 /* There was no conflict. We're done laying out this field. */
3492 /* Now that we know where it will be placed, update its
3494 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3495 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3496 this point because their BINFO_OFFSET is copied from another
3497 hierarchy. Therefore, we may not need to add the entire
3499 propagate_binfo_offsets (binfo,
3500 size_diffop (convert (ssizetype, offset),
3502 BINFO_OFFSET (binfo))));
3505 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3508 empty_base_at_nonzero_offset_p (tree type,
3510 splay_tree offsets ATTRIBUTE_UNUSED)
3512 return is_empty_class (type) && !integer_zerop (offset);
3515 /* Layout the empty base BINFO. EOC indicates the byte currently just
3516 past the end of the class, and should be correctly aligned for a
3517 class of the type indicated by BINFO; OFFSETS gives the offsets of
3518 the empty bases allocated so far. T is the most derived
3519 type. Return nonzero iff we added it at the end. */
3522 layout_empty_base (tree binfo, tree eoc, splay_tree offsets)
3525 tree basetype = BINFO_TYPE (binfo);
3528 /* This routine should only be used for empty classes. */
3529 gcc_assert (is_empty_class (basetype));
3530 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3532 if (!integer_zerop (BINFO_OFFSET (binfo)))
3534 if (abi_version_at_least (2))
3535 propagate_binfo_offsets
3536 (binfo, size_diffop (size_zero_node, BINFO_OFFSET (binfo)));
3538 warning ("offset of empty base `%T' may not be ABI-compliant and may"
3539 "change in a future version of GCC",
3540 BINFO_TYPE (binfo));
3543 /* This is an empty base class. We first try to put it at offset
3545 if (layout_conflict_p (binfo,
3546 BINFO_OFFSET (binfo),
3550 /* That didn't work. Now, we move forward from the next
3551 available spot in the class. */
3553 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3556 if (!layout_conflict_p (binfo,
3557 BINFO_OFFSET (binfo),
3560 /* We finally found a spot where there's no overlap. */
3563 /* There's overlap here, too. Bump along to the next spot. */
3564 propagate_binfo_offsets (binfo, alignment);
3570 /* Layout the the base given by BINFO in the class indicated by RLI.
3571 *BASE_ALIGN is a running maximum of the alignments of
3572 any base class. OFFSETS gives the location of empty base
3573 subobjects. T is the most derived type. Return nonzero if the new
3574 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3575 *NEXT_FIELD, unless BINFO is for an empty base class.
3577 Returns the location at which the next field should be inserted. */
3580 build_base_field (record_layout_info rli, tree binfo,
3581 splay_tree offsets, tree *next_field)
3584 tree basetype = BINFO_TYPE (binfo);
3586 if (!COMPLETE_TYPE_P (basetype))
3587 /* This error is now reported in xref_tag, thus giving better
3588 location information. */
3591 /* Place the base class. */
3592 if (!is_empty_class (basetype))
3596 /* The containing class is non-empty because it has a non-empty
3598 CLASSTYPE_EMPTY_P (t) = 0;
3600 /* Create the FIELD_DECL. */
3601 decl = build_decl (FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3602 DECL_ARTIFICIAL (decl) = 1;
3603 DECL_FIELD_CONTEXT (decl) = t;
3604 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3605 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3606 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3607 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3608 DECL_IGNORED_P (decl) = 1;
3609 DECL_FIELD_IS_BASE (decl) = 1;
3611 /* Try to place the field. It may take more than one try if we
3612 have a hard time placing the field without putting two
3613 objects of the same type at the same address. */
3614 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3615 /* Add the new FIELD_DECL to the list of fields for T. */
3616 TREE_CHAIN (decl) = *next_field;
3618 next_field = &TREE_CHAIN (decl);
3625 /* On some platforms (ARM), even empty classes will not be
3627 eoc = round_up (rli_size_unit_so_far (rli),
3628 CLASSTYPE_ALIGN_UNIT (basetype));
3629 atend = layout_empty_base (binfo, eoc, offsets);
3630 /* A nearly-empty class "has no proper base class that is empty,
3631 not morally virtual, and at an offset other than zero." */
3632 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3635 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3636 /* The check above (used in G++ 3.2) is insufficient because
3637 an empty class placed at offset zero might itself have an
3638 empty base at a nonzero offset. */
3639 else if (walk_subobject_offsets (basetype,
3640 empty_base_at_nonzero_offset_p,
3643 /*max_offset=*/NULL_TREE,
3646 if (abi_version_at_least (2))
3647 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3649 warning ("class `%T' will be considered nearly empty in a "
3650 "future version of GCC", t);
3654 /* We do not create a FIELD_DECL for empty base classes because
3655 it might overlap some other field. We want to be able to
3656 create CONSTRUCTORs for the class by iterating over the
3657 FIELD_DECLs, and the back end does not handle overlapping
3660 /* An empty virtual base causes a class to be non-empty
3661 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3662 here because that was already done when the virtual table
3663 pointer was created. */
3666 /* Record the offsets of BINFO and its base subobjects. */
3667 record_subobject_offsets (binfo,
3668 BINFO_OFFSET (binfo),
3675 /* Layout all of the non-virtual base classes. Record empty
3676 subobjects in OFFSETS. T is the most derived type. Return nonzero
3677 if the type cannot be nearly empty. The fields created
3678 corresponding to the base classes will be inserted at
3682 build_base_fields (record_layout_info rli,
3683 splay_tree offsets, tree *next_field)
3685 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3688 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3691 /* The primary base class is always allocated first. */
3692 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3693 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3694 offsets, next_field);
3696 /* Now allocate the rest of the bases. */
3697 for (i = 0; i < n_baseclasses; ++i)
3701 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3703 /* The primary base was already allocated above, so we don't
3704 need to allocate it again here. */
3705 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3708 /* Virtual bases are added at the end (a primary virtual base
3709 will have already been added). */
3710 if (BINFO_VIRTUAL_P (base_binfo))
3713 next_field = build_base_field (rli, base_binfo,
3714 offsets, next_field);
3718 /* Go through the TYPE_METHODS of T issuing any appropriate
3719 diagnostics, figuring out which methods override which other
3720 methods, and so forth. */
3723 check_methods (tree t)
3727 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3729 check_for_override (x, t);
3730 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3731 cp_error_at ("initializer specified for non-virtual method `%D'", x);
3732 /* The name of the field is the original field name
3733 Save this in auxiliary field for later overloading. */
3734 if (DECL_VINDEX (x))
3736 TYPE_POLYMORPHIC_P (t) = 1;
3737 if (DECL_PURE_VIRTUAL_P (x))
3738 VEC_safe_push (tree, CLASSTYPE_PURE_VIRTUALS (t), x);
3743 /* FN is a constructor or destructor. Clone the declaration to create
3744 a specialized in-charge or not-in-charge version, as indicated by
3748 build_clone (tree fn, tree name)
3753 /* Copy the function. */
3754 clone = copy_decl (fn);
3755 /* Remember where this function came from. */
3756 DECL_CLONED_FUNCTION (clone) = fn;
3757 DECL_ABSTRACT_ORIGIN (clone) = fn;
3758 /* Reset the function name. */
3759 DECL_NAME (clone) = name;
3760 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3761 /* There's no pending inline data for this function. */
3762 DECL_PENDING_INLINE_INFO (clone) = NULL;
3763 DECL_PENDING_INLINE_P (clone) = 0;
3764 /* And it hasn't yet been deferred. */
3765 DECL_DEFERRED_FN (clone) = 0;
3767 /* The base-class destructor is not virtual. */
3768 if (name == base_dtor_identifier)
3770 DECL_VIRTUAL_P (clone) = 0;
3771 if (TREE_CODE (clone) != TEMPLATE_DECL)
3772 DECL_VINDEX (clone) = NULL_TREE;
3775 /* If there was an in-charge parameter, drop it from the function
3777 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3783 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3784 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3785 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3786 /* Skip the `this' parameter. */
3787 parmtypes = TREE_CHAIN (parmtypes);
3788 /* Skip the in-charge parameter. */
3789 parmtypes = TREE_CHAIN (parmtypes);
3790 /* And the VTT parm, in a complete [cd]tor. */
3791 if (DECL_HAS_VTT_PARM_P (fn)
3792 && ! DECL_NEEDS_VTT_PARM_P (clone))
3793 parmtypes = TREE_CHAIN (parmtypes);
3794 /* If this is subobject constructor or destructor, add the vtt
3797 = build_method_type_directly (basetype,
3798 TREE_TYPE (TREE_TYPE (clone)),
3801 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3804 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3805 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3808 /* Copy the function parameters. But, DECL_ARGUMENTS on a TEMPLATE_DECL
3809 aren't function parameters; those are the template parameters. */
3810 if (TREE_CODE (clone) != TEMPLATE_DECL)
3812 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3813 /* Remove the in-charge parameter. */
3814 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3816 TREE_CHAIN (DECL_ARGUMENTS (clone))
3817 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3818 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3820 /* And the VTT parm, in a complete [cd]tor. */
3821 if (DECL_HAS_VTT_PARM_P (fn))
3823 if (DECL_NEEDS_VTT_PARM_P (clone))
3824 DECL_HAS_VTT_PARM_P (clone) = 1;
3827 TREE_CHAIN (DECL_ARGUMENTS (clone))
3828 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3829 DECL_HAS_VTT_PARM_P (clone) = 0;
3833 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3835 DECL_CONTEXT (parms) = clone;
3836 cxx_dup_lang_specific_decl (parms);
3840 /* Create the RTL for this function. */
3841 SET_DECL_RTL (clone, NULL_RTX);
3842 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3844 /* Make it easy to find the CLONE given the FN. */
3845 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3846 TREE_CHAIN (fn) = clone;
3848 /* If this is a template, handle the DECL_TEMPLATE_RESULT as well. */
3849 if (TREE_CODE (clone) == TEMPLATE_DECL)
3853 DECL_TEMPLATE_RESULT (clone)
3854 = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3855 result = DECL_TEMPLATE_RESULT (clone);
3856 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3857 DECL_TI_TEMPLATE (result) = clone;
3863 /* Produce declarations for all appropriate clones of FN. If
3864 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
3865 CLASTYPE_METHOD_VEC as well. */
3868 clone_function_decl (tree fn, int update_method_vec_p)
3872 /* Avoid inappropriate cloning. */
3874 && DECL_CLONED_FUNCTION (TREE_CHAIN (fn)))
3877 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
3879 /* For each constructor, we need two variants: an in-charge version
3880 and a not-in-charge version. */
3881 clone = build_clone (fn, complete_ctor_identifier);
3882 if (update_method_vec_p)
3883 add_method (DECL_CONTEXT (clone), clone);
3884 clone = build_clone (fn, base_ctor_identifier);
3885 if (update_method_vec_p)
3886 add_method (DECL_CONTEXT (clone), clone);
3890 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
3892 /* For each destructor, we need three variants: an in-charge
3893 version, a not-in-charge version, and an in-charge deleting
3894 version. We clone the deleting version first because that
3895 means it will go second on the TYPE_METHODS list -- and that
3896 corresponds to the correct layout order in the virtual
3899 For a non-virtual destructor, we do not build a deleting
3901 if (DECL_VIRTUAL_P (fn))
3903 clone = build_clone (fn, deleting_dtor_identifier);
3904 if (update_method_vec_p)
3905 add_method (DECL_CONTEXT (clone), clone);
3907 clone = build_clone (fn, complete_dtor_identifier);
3908 if (update_method_vec_p)
3909 add_method (DECL_CONTEXT (clone), clone);
3910 clone = build_clone (fn, base_dtor_identifier);
3911 if (update_method_vec_p)
3912 add_method (DECL_CONTEXT (clone), clone);
3915 /* Note that this is an abstract function that is never emitted. */
3916 DECL_ABSTRACT (fn) = 1;
3919 /* DECL is an in charge constructor, which is being defined. This will
3920 have had an in class declaration, from whence clones were
3921 declared. An out-of-class definition can specify additional default
3922 arguments. As it is the clones that are involved in overload
3923 resolution, we must propagate the information from the DECL to its
3927 adjust_clone_args (tree decl)
3931 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION (clone);
3932 clone = TREE_CHAIN (clone))
3934 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
3935 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
3936 tree decl_parms, clone_parms;
3938 clone_parms = orig_clone_parms;
3940 /* Skip the 'this' parameter. */
3941 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
3942 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3944 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
3945 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3946 if (DECL_HAS_VTT_PARM_P (decl))
3947 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3949 clone_parms = orig_clone_parms;
3950 if (DECL_HAS_VTT_PARM_P (clone))
3951 clone_parms = TREE_CHAIN (clone_parms);
3953 for (decl_parms = orig_decl_parms; decl_parms;
3954 decl_parms = TREE_CHAIN (decl_parms),
3955 clone_parms = TREE_CHAIN (clone_parms))
3957 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
3958 TREE_TYPE (clone_parms)));
3960 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
3962 /* A default parameter has been added. Adjust the
3963 clone's parameters. */
3964 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3965 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3968 clone_parms = orig_decl_parms;
3970 if (DECL_HAS_VTT_PARM_P (clone))
3972 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
3973 TREE_VALUE (orig_clone_parms),
3975 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
3977 type = build_method_type_directly (basetype,
3978 TREE_TYPE (TREE_TYPE (clone)),
3981 type = build_exception_variant (type, exceptions);
3982 TREE_TYPE (clone) = type;
3984 clone_parms = NULL_TREE;
3988 gcc_assert (!clone_parms);
3992 /* For each of the constructors and destructors in T, create an
3993 in-charge and not-in-charge variant. */
3996 clone_constructors_and_destructors (tree t)
4000 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4002 if (!CLASSTYPE_METHOD_VEC (t))
4005 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4006 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4007 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4008 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4011 /* Remove all zero-width bit-fields from T. */
4014 remove_zero_width_bit_fields (tree t)
4018 fieldsp = &TYPE_FIELDS (t);
4021 if (TREE_CODE (*fieldsp) == FIELD_DECL
4022 && DECL_C_BIT_FIELD (*fieldsp)
4023 && DECL_INITIAL (*fieldsp))
4024 *fieldsp = TREE_CHAIN (*fieldsp);
4026 fieldsp = &TREE_CHAIN (*fieldsp);
4030 /* Returns TRUE iff we need a cookie when dynamically allocating an
4031 array whose elements have the indicated class TYPE. */
4034 type_requires_array_cookie (tree type)
4037 bool has_two_argument_delete_p = false;
4039 gcc_assert (CLASS_TYPE_P (type));
4041 /* If there's a non-trivial destructor, we need a cookie. In order
4042 to iterate through the array calling the destructor for each
4043 element, we'll have to know how many elements there are. */
4044 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4047 /* If the usual deallocation function is a two-argument whose second
4048 argument is of type `size_t', then we have to pass the size of
4049 the array to the deallocation function, so we will need to store
4051 fns = lookup_fnfields (TYPE_BINFO (type),
4052 ansi_opname (VEC_DELETE_EXPR),
4054 /* If there are no `operator []' members, or the lookup is
4055 ambiguous, then we don't need a cookie. */
4056 if (!fns || fns == error_mark_node)
4058 /* Loop through all of the functions. */
4059 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4064 /* Select the current function. */
4065 fn = OVL_CURRENT (fns);
4066 /* See if this function is a one-argument delete function. If
4067 it is, then it will be the usual deallocation function. */
4068 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4069 if (second_parm == void_list_node)
4071 /* Otherwise, if we have a two-argument function and the second
4072 argument is `size_t', it will be the usual deallocation
4073 function -- unless there is one-argument function, too. */
4074 if (TREE_CHAIN (second_parm) == void_list_node
4075 && same_type_p (TREE_VALUE (second_parm), sizetype))
4076 has_two_argument_delete_p = true;
4079 return has_two_argument_delete_p;
4082 /* Check the validity of the bases and members declared in T. Add any
4083 implicitly-generated functions (like copy-constructors and
4084 assignment operators). Compute various flag bits (like
4085 CLASSTYPE_NON_POD_T) for T. This routine works purely at the C++
4086 level: i.e., independently of the ABI in use. */
4089 check_bases_and_members (tree t)
4091 /* Nonzero if we are not allowed to generate a default constructor
4093 int cant_have_default_ctor;
4094 /* Nonzero if the implicitly generated copy constructor should take
4095 a non-const reference argument. */
4096 int cant_have_const_ctor;
4097 /* Nonzero if the the implicitly generated assignment operator
4098 should take a non-const reference argument. */
4099 int no_const_asn_ref;
4102 /* By default, we use const reference arguments and generate default
4104 cant_have_default_ctor = 0;
4105 cant_have_const_ctor = 0;
4106 no_const_asn_ref = 0;
4108 /* Check all the base-classes. */
4109 check_bases (t, &cant_have_default_ctor, &cant_have_const_ctor,
4112 /* Check all the data member declarations. */
4113 check_field_decls (t, &access_decls,
4114 &cant_have_default_ctor,
4115 &cant_have_const_ctor,
4118 /* Check all the method declarations. */
4121 /* A nearly-empty class has to be vptr-containing; a nearly empty
4122 class contains just a vptr. */
4123 if (!TYPE_CONTAINS_VPTR_P (t))
4124 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4126 /* Do some bookkeeping that will guide the generation of implicitly
4127 declared member functions. */
4128 TYPE_HAS_COMPLEX_INIT_REF (t)
4129 |= (TYPE_HAS_INIT_REF (t)
4130 || TYPE_USES_VIRTUAL_BASECLASSES (t)
4131 || TYPE_POLYMORPHIC_P (t));
4132 TYPE_NEEDS_CONSTRUCTING (t)
4133 |= (TYPE_HAS_CONSTRUCTOR (t)
4134 || TYPE_USES_VIRTUAL_BASECLASSES (t)
4135 || TYPE_POLYMORPHIC_P (t));
4136 CLASSTYPE_NON_AGGREGATE (t) |= (TYPE_HAS_CONSTRUCTOR (t)
4137 || TYPE_POLYMORPHIC_P (t));
4138 CLASSTYPE_NON_POD_P (t)
4139 |= (CLASSTYPE_NON_AGGREGATE (t) || TYPE_HAS_DESTRUCTOR (t)
4140 || TYPE_HAS_ASSIGN_REF (t));
4141 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
4142 |= TYPE_HAS_ASSIGN_REF (t) || TYPE_CONTAINS_VPTR_P (t);
4144 /* Synthesize any needed methods. */
4145 add_implicitly_declared_members (t, cant_have_default_ctor,
4146 cant_have_const_ctor,
4149 /* Create the in-charge and not-in-charge variants of constructors
4151 clone_constructors_and_destructors (t);
4153 /* Process the using-declarations. */
4154 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4155 handle_using_decl (TREE_VALUE (access_decls), t);
4157 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4158 finish_struct_methods (t);
4160 /* Figure out whether or not we will need a cookie when dynamically
4161 allocating an array of this type. */
4162 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4163 = type_requires_array_cookie (t);
4166 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4167 accordingly. If a new vfield was created (because T doesn't have a
4168 primary base class), then the newly created field is returned. It
4169 is not added to the TYPE_FIELDS list; it is the caller's
4170 responsibility to do that. Accumulate declared virtual functions
4174 create_vtable_ptr (tree t, tree* virtuals_p)
4178 /* Collect the virtual functions declared in T. */
4179 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4180 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4181 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4183 tree new_virtual = make_node (TREE_LIST);
4185 BV_FN (new_virtual) = fn;
4186 BV_DELTA (new_virtual) = integer_zero_node;
4187 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4189 TREE_CHAIN (new_virtual) = *virtuals_p;
4190 *virtuals_p = new_virtual;
4193 /* If we couldn't find an appropriate base class, create a new field
4194 here. Even if there weren't any new virtual functions, we might need a
4195 new virtual function table if we're supposed to include vptrs in
4196 all classes that need them. */
4197 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4199 /* We build this decl with vtbl_ptr_type_node, which is a
4200 `vtable_entry_type*'. It might seem more precise to use
4201 `vtable_entry_type (*)[N]' where N is the number of virtual
4202 functions. However, that would require the vtable pointer in
4203 base classes to have a different type than the vtable pointer
4204 in derived classes. We could make that happen, but that
4205 still wouldn't solve all the problems. In particular, the
4206 type-based alias analysis code would decide that assignments
4207 to the base class vtable pointer can't alias assignments to
4208 the derived class vtable pointer, since they have different
4209 types. Thus, in a derived class destructor, where the base
4210 class constructor was inlined, we could generate bad code for
4211 setting up the vtable pointer.
4213 Therefore, we use one type for all vtable pointers. We still
4214 use a type-correct type; it's just doesn't indicate the array
4215 bounds. That's better than using `void*' or some such; it's
4216 cleaner, and it let's the alias analysis code know that these
4217 stores cannot alias stores to void*! */
4220 field = build_decl (FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4221 SET_DECL_ASSEMBLER_NAME (field, get_identifier (VFIELD_BASE));
4222 DECL_VIRTUAL_P (field) = 1;
4223 DECL_ARTIFICIAL (field) = 1;
4224 DECL_FIELD_CONTEXT (field) = t;
4225 DECL_FCONTEXT (field) = t;
4227 TYPE_VFIELD (t) = field;
4229 /* This class is non-empty. */
4230 CLASSTYPE_EMPTY_P (t) = 0;
4232 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)))
4233 /* If there were any baseclasses, they can't possibly be at
4234 offset zero any more, because that's where the vtable
4235 pointer is. So, converting to a base class is going to
4237 TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (t) = 1;
4245 /* Fixup the inline function given by INFO now that the class is
4249 fixup_pending_inline (tree fn)
4251 if (DECL_PENDING_INLINE_INFO (fn))
4253 tree args = DECL_ARGUMENTS (fn);
4256 DECL_CONTEXT (args) = fn;
4257 args = TREE_CHAIN (args);
4262 /* Fixup the inline methods and friends in TYPE now that TYPE is
4266 fixup_inline_methods (tree type)
4268 tree method = TYPE_METHODS (type);
4269 VEC (tree) *friends;
4272 if (method && TREE_CODE (method) == TREE_VEC)
4274 if (TREE_VEC_ELT (method, 1))
4275 method = TREE_VEC_ELT (method, 1);
4276 else if (TREE_VEC_ELT (method, 0))
4277 method = TREE_VEC_ELT (method, 0);
4279 method = TREE_VEC_ELT (method, 2);
4282 /* Do inline member functions. */
4283 for (; method; method = TREE_CHAIN (method))
4284 fixup_pending_inline (method);
4287 for (friends = CLASSTYPE_INLINE_FRIENDS (type), ix = 0;
4288 VEC_iterate (tree, friends, ix, method); ix++)
4289 fixup_pending_inline (method);
4290 CLASSTYPE_INLINE_FRIENDS (type) = NULL;
4293 /* Add OFFSET to all base types of BINFO which is a base in the
4294 hierarchy dominated by T.
4296 OFFSET, which is a type offset, is number of bytes. */
4299 propagate_binfo_offsets (tree binfo, tree offset)
4305 /* Update BINFO's offset. */
4306 BINFO_OFFSET (binfo)
4307 = convert (sizetype,
4308 size_binop (PLUS_EXPR,
4309 convert (ssizetype, BINFO_OFFSET (binfo)),
4312 /* Find the primary base class. */
4313 primary_binfo = get_primary_binfo (binfo);
4315 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4316 propagate_binfo_offsets (primary_binfo, offset);
4318 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4320 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4322 /* Don't do the primary base twice. */
4323 if (base_binfo == primary_binfo)
4326 if (BINFO_VIRTUAL_P (base_binfo))
4329 propagate_binfo_offsets (base_binfo, offset);
4333 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4334 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4335 empty subobjects of T. */
4338 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4342 bool first_vbase = true;
4345 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4348 if (!abi_version_at_least(2))
4350 /* In G++ 3.2, we incorrectly rounded the size before laying out
4351 the virtual bases. */
4352 finish_record_layout (rli, /*free_p=*/false);
4353 #ifdef STRUCTURE_SIZE_BOUNDARY
4354 /* Packed structures don't need to have minimum size. */
4355 if (! TYPE_PACKED (t))
4356 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4358 rli->offset = TYPE_SIZE_UNIT (t);
4359 rli->bitpos = bitsize_zero_node;
4360 rli->record_align = TYPE_ALIGN (t);
4363 /* Find the last field. The artificial fields created for virtual
4364 bases will go after the last extant field to date. */
4365 next_field = &TYPE_FIELDS (t);
4367 next_field = &TREE_CHAIN (*next_field);
4369 /* Go through the virtual bases, allocating space for each virtual
4370 base that is not already a primary base class. These are
4371 allocated in inheritance graph order. */
4372 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4374 if (!BINFO_VIRTUAL_P (vbase))
4377 if (!BINFO_PRIMARY_P (vbase))
4379 tree basetype = TREE_TYPE (vbase);
4381 /* This virtual base is not a primary base of any class in the
4382 hierarchy, so we have to add space for it. */
4383 next_field = build_base_field (rli, vbase,
4384 offsets, next_field);
4386 /* If the first virtual base might have been placed at a
4387 lower address, had we started from CLASSTYPE_SIZE, rather
4388 than TYPE_SIZE, issue a warning. There can be both false
4389 positives and false negatives from this warning in rare
4390 cases; to deal with all the possibilities would probably
4391 require performing both layout algorithms and comparing
4392 the results which is not particularly tractable. */
4396 (size_binop (CEIL_DIV_EXPR,
4397 round_up (CLASSTYPE_SIZE (t),
4398 CLASSTYPE_ALIGN (basetype)),
4400 BINFO_OFFSET (vbase))))
4401 warning ("offset of virtual base `%T' is not ABI-compliant and may change in a future version of GCC",
4404 first_vbase = false;
4409 /* Returns the offset of the byte just past the end of the base class
4413 end_of_base (tree binfo)
4417 if (is_empty_class (BINFO_TYPE (binfo)))
4418 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4419 allocate some space for it. It cannot have virtual bases, so
4420 TYPE_SIZE_UNIT is fine. */
4421 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4423 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4425 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4428 /* Returns the offset of the byte just past the end of the base class
4429 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4430 only non-virtual bases are included. */
4433 end_of_class (tree t, int include_virtuals_p)
4435 tree result = size_zero_node;
4442 for (binfo = TYPE_BINFO (t), i = 0;
4443 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4445 if (!include_virtuals_p
4446 && BINFO_VIRTUAL_P (base_binfo)
4447 && (!BINFO_PRIMARY_P (base_binfo)
4448 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4451 offset = end_of_base (base_binfo);
4452 if (INT_CST_LT_UNSIGNED (result, offset))
4456 /* G++ 3.2 did not check indirect virtual bases. */
4457 if (abi_version_at_least (2) && include_virtuals_p)
4458 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4459 VEC_iterate (tree, vbases, i, base_binfo); i++)
4461 offset = end_of_base (base_binfo);
4462 if (INT_CST_LT_UNSIGNED (result, offset))
4469 /* Warn about bases of T that are inaccessible because they are
4470 ambiguous. For example:
4473 struct T : public S {};
4474 struct U : public S, public T {};
4476 Here, `(S*) new U' is not allowed because there are two `S'
4480 warn_about_ambiguous_bases (tree t)
4488 /* Check direct bases. */
4489 for (binfo = TYPE_BINFO (t), i = 0;
4490 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4492 basetype = BINFO_TYPE (base_binfo);
4494 if (!lookup_base (t, basetype, ba_ignore | ba_quiet, NULL))
4495 warning ("direct base `%T' inaccessible in `%T' due to ambiguity",
4499 /* Check for ambiguous virtual bases. */
4501 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4502 VEC_iterate (tree, vbases, i, binfo); i++)
4504 basetype = BINFO_TYPE (binfo);
4506 if (!lookup_base (t, basetype, ba_ignore | ba_quiet, NULL))
4507 warning ("virtual base `%T' inaccessible in `%T' due to ambiguity",
4512 /* Compare two INTEGER_CSTs K1 and K2. */
4515 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4517 return tree_int_cst_compare ((tree) k1, (tree) k2);
4520 /* Increase the size indicated in RLI to account for empty classes
4521 that are "off the end" of the class. */
4524 include_empty_classes (record_layout_info rli)
4529 /* It might be the case that we grew the class to allocate a
4530 zero-sized base class. That won't be reflected in RLI, yet,
4531 because we are willing to overlay multiple bases at the same
4532 offset. However, now we need to make sure that RLI is big enough
4533 to reflect the entire class. */
4534 eoc = end_of_class (rli->t,
4535 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4536 rli_size = rli_size_unit_so_far (rli);
4537 if (TREE_CODE (rli_size) == INTEGER_CST
4538 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4540 if (!abi_version_at_least (2))
4541 /* In version 1 of the ABI, the size of a class that ends with
4542 a bitfield was not rounded up to a whole multiple of a
4543 byte. Because rli_size_unit_so_far returns only the number
4544 of fully allocated bytes, any extra bits were not included
4546 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4548 /* The size should have been rounded to a whole byte. */
4549 gcc_assert (tree_int_cst_equal
4550 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4552 = size_binop (PLUS_EXPR,
4554 size_binop (MULT_EXPR,
4555 convert (bitsizetype,
4556 size_binop (MINUS_EXPR,
4558 bitsize_int (BITS_PER_UNIT)));
4559 normalize_rli (rli);
4563 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4564 BINFO_OFFSETs for all of the base-classes. Position the vtable
4565 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4568 layout_class_type (tree t, tree *virtuals_p)
4570 tree non_static_data_members;
4573 record_layout_info rli;
4574 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4575 types that appear at that offset. */
4576 splay_tree empty_base_offsets;
4577 /* True if the last field layed out was a bit-field. */
4578 bool last_field_was_bitfield = false;
4579 /* The location at which the next field should be inserted. */
4581 /* T, as a base class. */
4584 /* Keep track of the first non-static data member. */
4585 non_static_data_members = TYPE_FIELDS (t);
4587 /* Start laying out the record. */
4588 rli = start_record_layout (t);
4590 /* Mark all the primary bases in the hierarchy. */
4591 determine_primary_bases (t);
4593 /* Create a pointer to our virtual function table. */
4594 vptr = create_vtable_ptr (t, virtuals_p);
4596 /* The vptr is always the first thing in the class. */
4599 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4600 TYPE_FIELDS (t) = vptr;
4601 next_field = &TREE_CHAIN (vptr);
4602 place_field (rli, vptr);
4605 next_field = &TYPE_FIELDS (t);
4607 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4608 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4610 build_base_fields (rli, empty_base_offsets, next_field);
4612 /* Layout the non-static data members. */
4613 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4618 /* We still pass things that aren't non-static data members to
4619 the back-end, in case it wants to do something with them. */
4620 if (TREE_CODE (field) != FIELD_DECL)
4622 place_field (rli, field);
4623 /* If the static data member has incomplete type, keep track
4624 of it so that it can be completed later. (The handling
4625 of pending statics in finish_record_layout is
4626 insufficient; consider:
4629 struct S2 { static S1 s1; };
4631 At this point, finish_record_layout will be called, but
4632 S1 is still incomplete.) */
4633 if (TREE_CODE (field) == VAR_DECL)
4634 maybe_register_incomplete_var (field);
4638 type = TREE_TYPE (field);
4640 padding = NULL_TREE;
4642 /* If this field is a bit-field whose width is greater than its
4643 type, then there are some special rules for allocating
4645 if (DECL_C_BIT_FIELD (field)
4646 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4648 integer_type_kind itk;
4650 bool was_unnamed_p = false;
4651 /* We must allocate the bits as if suitably aligned for the
4652 longest integer type that fits in this many bits. type
4653 of the field. Then, we are supposed to use the left over
4654 bits as additional padding. */
4655 for (itk = itk_char; itk != itk_none; ++itk)
4656 if (INT_CST_LT (DECL_SIZE (field),
4657 TYPE_SIZE (integer_types[itk])))
4660 /* ITK now indicates a type that is too large for the
4661 field. We have to back up by one to find the largest
4663 integer_type = integer_types[itk - 1];
4665 /* Figure out how much additional padding is required. GCC
4666 3.2 always created a padding field, even if it had zero
4668 if (!abi_version_at_least (2)
4669 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4671 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4672 /* In a union, the padding field must have the full width
4673 of the bit-field; all fields start at offset zero. */
4674 padding = DECL_SIZE (field);
4677 if (warn_abi && TREE_CODE (t) == UNION_TYPE)
4678 warning ("size assigned to `%T' may not be "
4679 "ABI-compliant and may change in a future "
4682 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4683 TYPE_SIZE (integer_type));
4686 #ifdef PCC_BITFIELD_TYPE_MATTERS
4687 /* An unnamed bitfield does not normally affect the
4688 alignment of the containing class on a target where
4689 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4690 make any exceptions for unnamed bitfields when the
4691 bitfields are longer than their types. Therefore, we
4692 temporarily give the field a name. */
4693 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4695 was_unnamed_p = true;
4696 DECL_NAME (field) = make_anon_name ();
4699 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4700 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4701 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4702 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4703 empty_base_offsets);
4705 DECL_NAME (field) = NULL_TREE;
4706 /* Now that layout has been performed, set the size of the
4707 field to the size of its declared type; the rest of the
4708 field is effectively invisible. */
4709 DECL_SIZE (field) = TYPE_SIZE (type);
4710 /* We must also reset the DECL_MODE of the field. */
4711 if (abi_version_at_least (2))
4712 DECL_MODE (field) = TYPE_MODE (type);
4714 && DECL_MODE (field) != TYPE_MODE (type))
4715 /* Versions of G++ before G++ 3.4 did not reset the
4717 warning ("the offset of `%D' may not be ABI-compliant and may "
4718 "change in a future version of GCC", field);
4721 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4722 empty_base_offsets);
4724 /* Remember the location of any empty classes in FIELD. */
4725 if (abi_version_at_least (2))
4726 record_subobject_offsets (TREE_TYPE (field),
4727 byte_position(field),
4731 /* If a bit-field does not immediately follow another bit-field,
4732 and yet it starts in the middle of a byte, we have failed to
4733 comply with the ABI. */
4735 && DECL_C_BIT_FIELD (field)
4736 && !last_field_was_bitfield
4737 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
4738 DECL_FIELD_BIT_OFFSET (field),
4739 bitsize_unit_node)))
4740 cp_warning_at ("offset of `%D' is not ABI-compliant and may change in a future version of GCC",
4743 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
4744 offset of the field. */
4746 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
4747 byte_position (field))
4748 && contains_empty_class_p (TREE_TYPE (field)))
4749 cp_warning_at ("`%D' contains empty classes which may cause base "
4750 "classes to be placed at different locations in a "
4751 "future version of GCC",
4754 /* If we needed additional padding after this field, add it
4760 padding_field = build_decl (FIELD_DECL,
4763 DECL_BIT_FIELD (padding_field) = 1;
4764 DECL_SIZE (padding_field) = padding;
4765 DECL_CONTEXT (padding_field) = t;
4766 DECL_ARTIFICIAL (padding_field) = 1;
4767 layout_nonempty_base_or_field (rli, padding_field,
4769 empty_base_offsets);
4772 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
4775 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
4777 /* Make sure that we are on a byte boundary so that the size of
4778 the class without virtual bases will always be a round number
4780 rli->bitpos = round_up (rli->bitpos, BITS_PER_UNIT);
4781 normalize_rli (rli);
4784 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
4786 if (!abi_version_at_least (2))
4787 include_empty_classes(rli);
4789 /* Delete all zero-width bit-fields from the list of fields. Now
4790 that the type is laid out they are no longer important. */
4791 remove_zero_width_bit_fields (t);
4793 /* Create the version of T used for virtual bases. We do not use
4794 make_aggr_type for this version; this is an artificial type. For
4795 a POD type, we just reuse T. */
4796 if (CLASSTYPE_NON_POD_P (t) || CLASSTYPE_EMPTY_P (t))
4798 base_t = make_node (TREE_CODE (t));
4800 /* Set the size and alignment for the new type. In G++ 3.2, all
4801 empty classes were considered to have size zero when used as
4803 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
4805 TYPE_SIZE (base_t) = bitsize_zero_node;
4806 TYPE_SIZE_UNIT (base_t) = size_zero_node;
4807 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
4808 warning ("layout of classes derived from empty class `%T' "
4809 "may change in a future version of GCC",
4816 /* If the ABI version is not at least two, and the last
4817 field was a bit-field, RLI may not be on a byte
4818 boundary. In particular, rli_size_unit_so_far might
4819 indicate the last complete byte, while rli_size_so_far
4820 indicates the total number of bits used. Therefore,
4821 rli_size_so_far, rather than rli_size_unit_so_far, is
4822 used to compute TYPE_SIZE_UNIT. */
4823 eoc = end_of_class (t, /*include_virtuals_p=*/0);
4824 TYPE_SIZE_UNIT (base_t)
4825 = size_binop (MAX_EXPR,
4827 size_binop (CEIL_DIV_EXPR,
4828 rli_size_so_far (rli),
4829 bitsize_int (BITS_PER_UNIT))),
4832 = size_binop (MAX_EXPR,
4833 rli_size_so_far (rli),
4834 size_binop (MULT_EXPR,
4835 convert (bitsizetype, eoc),
4836 bitsize_int (BITS_PER_UNIT)));
4838 TYPE_ALIGN (base_t) = rli->record_align;
4839 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
4841 /* Copy the fields from T. */
4842 next_field = &TYPE_FIELDS (base_t);
4843 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4844 if (TREE_CODE (field) == FIELD_DECL)
4846 *next_field = build_decl (FIELD_DECL,
4849 DECL_CONTEXT (*next_field) = base_t;
4850 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
4851 DECL_FIELD_BIT_OFFSET (*next_field)
4852 = DECL_FIELD_BIT_OFFSET (field);
4853 DECL_SIZE (*next_field) = DECL_SIZE (field);
4854 DECL_MODE (*next_field) = DECL_MODE (field);
4855 next_field = &TREE_CHAIN (*next_field);
4858 /* Record the base version of the type. */
4859 CLASSTYPE_AS_BASE (t) = base_t;
4860 TYPE_CONTEXT (base_t) = t;
4863 CLASSTYPE_AS_BASE (t) = t;
4865 /* Every empty class contains an empty class. */
4866 if (CLASSTYPE_EMPTY_P (t))
4867 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
4869 /* Set the TYPE_DECL for this type to contain the right
4870 value for DECL_OFFSET, so that we can use it as part
4871 of a COMPONENT_REF for multiple inheritance. */
4872 layout_decl (TYPE_MAIN_DECL (t), 0);
4874 /* Now fix up any virtual base class types that we left lying
4875 around. We must get these done before we try to lay out the
4876 virtual function table. As a side-effect, this will remove the
4877 base subobject fields. */
4878 layout_virtual_bases (rli, empty_base_offsets);
4880 /* Make sure that empty classes are reflected in RLI at this
4882 include_empty_classes(rli);
4884 /* Make sure not to create any structures with zero size. */
4885 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
4887 build_decl (FIELD_DECL, NULL_TREE, char_type_node));
4889 /* Let the back-end lay out the type. */
4890 finish_record_layout (rli, /*free_p=*/true);
4892 /* Warn about bases that can't be talked about due to ambiguity. */
4893 warn_about_ambiguous_bases (t);
4895 /* Now that we're done with layout, give the base fields the real types. */
4896 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4897 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
4898 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
4901 splay_tree_delete (empty_base_offsets);
4904 /* Determine the "key method" for the class type indicated by TYPE,
4905 and set CLASSTYPE_KEY_METHOD accordingly. */
4908 determine_key_method (tree type)
4912 if (TYPE_FOR_JAVA (type)
4913 || processing_template_decl
4914 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
4915 || CLASSTYPE_INTERFACE_KNOWN (type))
4918 /* The key method is the first non-pure virtual function that is not
4919 inline at the point of class definition. On some targets the
4920 key function may not be inline; those targets should not call
4921 this function until the end of the translation unit. */
4922 for (method = TYPE_METHODS (type); method != NULL_TREE;
4923 method = TREE_CHAIN (method))
4924 if (DECL_VINDEX (method) != NULL_TREE
4925 && ! DECL_DECLARED_INLINE_P (method)
4926 && ! DECL_PURE_VIRTUAL_P (method))
4928 CLASSTYPE_KEY_METHOD (type) = method;
4935 /* Perform processing required when the definition of T (a class type)
4939 finish_struct_1 (tree t)
4942 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
4943 tree virtuals = NULL_TREE;
4946 if (COMPLETE_TYPE_P (t))
4948 gcc_assert (IS_AGGR_TYPE (t));
4949 error ("redefinition of `%#T'", t);
4954 /* If this type was previously laid out as a forward reference,
4955 make sure we lay it out again. */
4956 TYPE_SIZE (t) = NULL_TREE;
4957 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
4959 fixup_inline_methods (t);
4961 /* Make assumptions about the class; we'll reset the flags if
4963 CLASSTYPE_EMPTY_P (t) = 1;
4964 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
4965 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
4967 /* Do end-of-class semantic processing: checking the validity of the
4968 bases and members and add implicitly generated methods. */
4969 check_bases_and_members (t);
4971 /* Find the key method. */
4972 if (TYPE_CONTAINS_VPTR_P (t))
4974 /* The Itanium C++ ABI permits the key method to be chosen when
4975 the class is defined -- even though the key method so
4976 selected may later turn out to be an inline function. On
4977 some systems (such as ARM Symbian OS) the key method cannot
4978 be determined until the end of the translation unit. On such
4979 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
4980 will cause the class to be added to KEYED_CLASSES. Then, in
4981 finish_file we will determine the key method. */
4982 if (targetm.cxx.key_method_may_be_inline ())
4983 determine_key_method (t);
4985 /* If a polymorphic class has no key method, we may emit the vtable
4986 in every translation unit where the class definition appears. */
4987 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
4988 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
4991 /* Layout the class itself. */
4992 layout_class_type (t, &virtuals);
4993 if (CLASSTYPE_AS_BASE (t) != t)
4994 /* We use the base type for trivial assignments, and hence it
4996 compute_record_mode (CLASSTYPE_AS_BASE (t));
4998 virtuals = modify_all_vtables (t, nreverse (virtuals));
5000 /* If necessary, create the primary vtable for this class. */
5001 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5003 /* We must enter these virtuals into the table. */
5004 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5005 build_primary_vtable (NULL_TREE, t);
5006 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5007 /* Here we know enough to change the type of our virtual
5008 function table, but we will wait until later this function. */
5009 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5012 if (TYPE_CONTAINS_VPTR_P (t))
5017 if (BINFO_VTABLE (TYPE_BINFO (t)))
5018 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5019 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5020 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5022 /* Add entries for virtual functions introduced by this class. */
5023 BINFO_VIRTUALS (TYPE_BINFO (t))
5024 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5026 /* Set DECL_VINDEX for all functions declared in this class. */
5027 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5029 fn = TREE_CHAIN (fn),
5030 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5031 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5033 tree fndecl = BV_FN (fn);
5035 if (DECL_THUNK_P (fndecl))
5036 /* A thunk. We should never be calling this entry directly
5037 from this vtable -- we'd use the entry for the non
5038 thunk base function. */
5039 DECL_VINDEX (fndecl) = NULL_TREE;
5040 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5041 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5045 finish_struct_bits (t);
5047 /* Complete the rtl for any static member objects of the type we're
5049 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5050 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5051 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5052 DECL_MODE (x) = TYPE_MODE (t);
5054 /* Done with FIELDS...now decide whether to sort these for
5055 faster lookups later.
5057 We use a small number because most searches fail (succeeding
5058 ultimately as the search bores through the inheritance
5059 hierarchy), and we want this failure to occur quickly. */
5061 n_fields = count_fields (TYPE_FIELDS (t));
5064 struct sorted_fields_type *field_vec = GGC_NEWVAR
5065 (struct sorted_fields_type,
5066 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5067 field_vec->len = n_fields;
5068 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5069 qsort (field_vec->elts, n_fields, sizeof (tree),
5071 if (! DECL_LANG_SPECIFIC (TYPE_MAIN_DECL (t)))
5072 retrofit_lang_decl (TYPE_MAIN_DECL (t));
5073 DECL_SORTED_FIELDS (TYPE_MAIN_DECL (t)) = field_vec;
5076 /* Make the rtl for any new vtables we have created, and unmark
5077 the base types we marked. */
5080 /* Build the VTT for T. */
5083 if (warn_nonvdtor && TYPE_POLYMORPHIC_P (t) && TYPE_HAS_DESTRUCTOR (t)
5084 && !DECL_VINDEX (CLASSTYPE_DESTRUCTORS (t)))
5087 tree dtor = CLASSTYPE_DESTRUCTORS (t);
5089 /* Warn only if the dtor is non-private or the class has friends */
5090 if (!TREE_PRIVATE (dtor) ||
5091 (CLASSTYPE_FRIEND_CLASSES (t) ||
5092 DECL_FRIENDLIST (TYPE_MAIN_DECL (t))))
5093 warning ("%#T' has virtual functions but non-virtual destructor", t);
5098 if (warn_overloaded_virtual)
5101 maybe_suppress_debug_info (t);
5103 dump_class_hierarchy (t);
5105 /* Finish debugging output for this type. */
5106 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5109 /* When T was built up, the member declarations were added in reverse
5110 order. Rearrange them to declaration order. */
5113 unreverse_member_declarations (tree t)
5119 /* The following lists are all in reverse order. Put them in
5120 declaration order now. */
5121 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5122 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5124 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5125 reverse order, so we can't just use nreverse. */
5127 for (x = TYPE_FIELDS (t);
5128 x && TREE_CODE (x) != TYPE_DECL;
5131 next = TREE_CHAIN (x);
5132 TREE_CHAIN (x) = prev;
5137 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5139 TYPE_FIELDS (t) = prev;
5144 finish_struct (tree t, tree attributes)
5146 location_t saved_loc = input_location;
5148 /* Now that we've got all the field declarations, reverse everything
5150 unreverse_member_declarations (t);
5152 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5154 /* Nadger the current location so that diagnostics point to the start of
5155 the struct, not the end. */
5156 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5158 if (processing_template_decl)
5162 finish_struct_methods (t);
5163 TYPE_SIZE (t) = bitsize_zero_node;
5165 /* We need to emit an error message if this type was used as a parameter
5166 and it is an abstract type, even if it is a template. We construct
5167 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5168 account and we call complete_vars with this type, which will check
5169 the PARM_DECLS. Note that while the type is being defined,
5170 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5171 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5172 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5173 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5174 if (DECL_PURE_VIRTUAL_P (x))
5175 VEC_safe_push (tree, CLASSTYPE_PURE_VIRTUALS (t), x);
5179 finish_struct_1 (t);
5181 input_location = saved_loc;
5183 TYPE_BEING_DEFINED (t) = 0;
5185 if (current_class_type)
5188 error ("trying to finish struct, but kicked out due to previous parse errors");
5190 if (processing_template_decl && at_function_scope_p ())
5191 add_stmt (build_min (TAG_DEFN, t));
5196 /* Return the dynamic type of INSTANCE, if known.
5197 Used to determine whether the virtual function table is needed
5200 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5201 of our knowledge of its type. *NONNULL should be initialized
5202 before this function is called. */
5205 fixed_type_or_null (tree instance, int* nonnull, int* cdtorp)
5207 switch (TREE_CODE (instance))
5210 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5213 return fixed_type_or_null (TREE_OPERAND (instance, 0),
5217 /* This is a call to a constructor, hence it's never zero. */
5218 if (TREE_HAS_CONSTRUCTOR (instance))
5222 return TREE_TYPE (instance);
5227 /* This is a call to a constructor, hence it's never zero. */
5228 if (TREE_HAS_CONSTRUCTOR (instance))
5232 return TREE_TYPE (instance);
5234 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5238 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5239 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5240 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5241 /* Propagate nonnull. */
5242 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5247 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5250 instance = TREE_OPERAND (instance, 0);
5253 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5254 with a real object -- given &p->f, p can still be null. */
5255 tree t = get_base_address (instance);
5256 /* ??? Probably should check DECL_WEAK here. */
5257 if (t && DECL_P (t))
5260 return fixed_type_or_null (instance, nonnull, cdtorp);
5263 /* If this component is really a base class reference, then the field
5264 itself isn't definitive. */
5265 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5266 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5267 return fixed_type_or_null (TREE_OPERAND (instance, 1), nonnull, cdtorp);
5271 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5272 && IS_AGGR_TYPE (TREE_TYPE (TREE_TYPE (instance))))
5276 return TREE_TYPE (TREE_TYPE (instance));
5278 /* fall through... */
5282 if (IS_AGGR_TYPE (TREE_TYPE (instance)))
5286 return TREE_TYPE (instance);
5288 else if (instance == current_class_ptr)
5293 /* if we're in a ctor or dtor, we know our type. */
5294 if (DECL_LANG_SPECIFIC (current_function_decl)
5295 && (DECL_CONSTRUCTOR_P (current_function_decl)
5296 || DECL_DESTRUCTOR_P (current_function_decl)))
5300 return TREE_TYPE (TREE_TYPE (instance));
5303 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5305 /* Reference variables should be references to objects. */
5309 /* DECL_VAR_MARKED_P is used to prevent recursion; a
5310 variable's initializer may refer to the variable
5312 if (TREE_CODE (instance) == VAR_DECL
5313 && DECL_INITIAL (instance)
5314 && !DECL_VAR_MARKED_P (instance))
5317 DECL_VAR_MARKED_P (instance) = 1;
5318 type = fixed_type_or_null (DECL_INITIAL (instance),
5320 DECL_VAR_MARKED_P (instance) = 0;
5331 /* Return nonzero if the dynamic type of INSTANCE is known, and
5332 equivalent to the static type. We also handle the case where
5333 INSTANCE is really a pointer. Return negative if this is a
5334 ctor/dtor. There the dynamic type is known, but this might not be
5335 the most derived base of the original object, and hence virtual
5336 bases may not be layed out according to this type.
5338 Used to determine whether the virtual function table is needed
5341 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5342 of our knowledge of its type. *NONNULL should be initialized
5343 before this function is called. */
5346 resolves_to_fixed_type_p (tree instance, int* nonnull)
5348 tree t = TREE_TYPE (instance);
5351 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5352 if (fixed == NULL_TREE)
5354 if (POINTER_TYPE_P (t))
5356 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5358 return cdtorp ? -1 : 1;
5363 init_class_processing (void)
5365 current_class_depth = 0;
5366 current_class_stack_size = 10;
5368 = xmalloc (current_class_stack_size * sizeof (struct class_stack_node));
5369 VARRAY_TREE_INIT (local_classes, 8, "local_classes");
5371 ridpointers[(int) RID_PUBLIC] = access_public_node;
5372 ridpointers[(int) RID_PRIVATE] = access_private_node;
5373 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5376 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5379 restore_class_cache (void)
5383 /* We are re-entering the same class we just left, so we don't
5384 have to search the whole inheritance matrix to find all the
5385 decls to bind again. Instead, we install the cached
5386 class_shadowed list and walk through it binding names. */
5387 push_binding_level (previous_class_level);
5388 class_binding_level = previous_class_level;
5389 /* Restore IDENTIFIER_TYPE_VALUE. */
5390 for (type = class_binding_level->type_shadowed;
5392 type = TREE_CHAIN (type))
5393 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5396 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5397 appropriate for TYPE.
5399 So that we may avoid calls to lookup_name, we cache the _TYPE
5400 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5402 For multiple inheritance, we perform a two-pass depth-first search
5403 of the type lattice. */
5406 pushclass (tree type)
5408 type = TYPE_MAIN_VARIANT (type);
5410 /* Make sure there is enough room for the new entry on the stack. */
5411 if (current_class_depth + 1 >= current_class_stack_size)
5413 current_class_stack_size *= 2;
5415 = xrealloc (current_class_stack,
5416 current_class_stack_size
5417 * sizeof (struct class_stack_node));
5420 /* Insert a new entry on the class stack. */
5421 current_class_stack[current_class_depth].name = current_class_name;
5422 current_class_stack[current_class_depth].type = current_class_type;
5423 current_class_stack[current_class_depth].access = current_access_specifier;
5424 current_class_stack[current_class_depth].names_used = 0;
5425 current_class_depth++;
5427 /* Now set up the new type. */
5428 current_class_name = TYPE_NAME (type);
5429 if (TREE_CODE (current_class_name) == TYPE_DECL)
5430 current_class_name = DECL_NAME (current_class_name);
5431 current_class_type = type;
5433 /* By default, things in classes are private, while things in
5434 structures or unions are public. */
5435 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5436 ? access_private_node
5437 : access_public_node);
5439 if (previous_class_level
5440 && type != previous_class_level->this_entity
5441 && current_class_depth == 1)
5443 /* Forcibly remove any old class remnants. */
5444 invalidate_class_lookup_cache ();
5447 if (!previous_class_level
5448 || type != previous_class_level->this_entity
5449 || current_class_depth > 1)
5452 restore_class_cache ();
5454 cxx_remember_type_decls (CLASSTYPE_NESTED_UTDS (type));
5457 /* When we exit a toplevel class scope, we save its binding level so
5458 that we can restore it quickly. Here, we've entered some other
5459 class, so we must invalidate our cache. */
5462 invalidate_class_lookup_cache (void)
5464 previous_class_level = NULL;
5467 /* Get out of the current class scope. If we were in a class scope
5468 previously, that is the one popped to. */
5475 current_class_depth--;
5476 current_class_name = current_class_stack[current_class_depth].name;
5477 current_class_type = current_class_stack[current_class_depth].type;
5478 current_access_specifier = current_class_stack[current_class_depth].access;
5479 if (current_class_stack[current_class_depth].names_used)
5480 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5483 /* Returns 1 if current_class_type is either T or a nested type of T.
5484 We start looking from 1 because entry 0 is from global scope, and has
5488 currently_open_class (tree t)
5491 if (current_class_type && same_type_p (t, current_class_type))
5493 for (i = 1; i < current_class_depth; ++i)
5494 if (current_class_stack[i].type
5495 && same_type_p (current_class_stack [i].type, t))
5500 /* If either current_class_type or one of its enclosing classes are derived
5501 from T, return the appropriate type. Used to determine how we found
5502 something via unqualified lookup. */
5505 currently_open_derived_class (tree t)
5509 /* The bases of a dependent type are unknown. */
5510 if (dependent_type_p (t))
5513 if (!current_class_type)
5516 if (DERIVED_FROM_P (t, current_class_type))
5517 return current_class_type;
5519 for (i = current_class_depth - 1; i > 0; --i)
5520 if (DERIVED_FROM_P (t, current_class_stack[i].type))
5521 return current_class_stack[i].type;
5526 /* When entering a class scope, all enclosing class scopes' names with
5527 static meaning (static variables, static functions, types and
5528 enumerators) have to be visible. This recursive function calls
5529 pushclass for all enclosing class contexts until global or a local
5530 scope is reached. TYPE is the enclosed class. */
5533 push_nested_class (tree type)
5537 /* A namespace might be passed in error cases, like A::B:C. */
5538 if (type == NULL_TREE
5539 || type == error_mark_node
5540 || TREE_CODE (type) == NAMESPACE_DECL
5541 || ! IS_AGGR_TYPE (type)
5542 || TREE_CODE (type) == TEMPLATE_TYPE_PARM
5543 || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
5546 context = DECL_CONTEXT (TYPE_MAIN_DECL (type));
5548 if (context && CLASS_TYPE_P (context))
5549 push_nested_class (context);
5553 /* Undoes a push_nested_class call. */
5556 pop_nested_class (void)
5558 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5561 if (context && CLASS_TYPE_P (context))
5562 pop_nested_class ();
5565 /* Returns the number of extern "LANG" blocks we are nested within. */
5568 current_lang_depth (void)
5570 return VARRAY_ACTIVE_SIZE (current_lang_base);
5573 /* Set global variables CURRENT_LANG_NAME to appropriate value
5574 so that behavior of name-mangling machinery is correct. */
5577 push_lang_context (tree name)
5579 VARRAY_PUSH_TREE (current_lang_base, current_lang_name);
5581 if (name == lang_name_cplusplus)
5583 current_lang_name = name;
5585 else if (name == lang_name_java)
5587 current_lang_name = name;
5588 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5589 (See record_builtin_java_type in decl.c.) However, that causes
5590 incorrect debug entries if these types are actually used.
5591 So we re-enable debug output after extern "Java". */
5592 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
5593 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
5594 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
5595 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
5596 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
5597 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
5598 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
5599 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
5601 else if (name == lang_name_c)
5603 current_lang_name = name;
5606 error ("language string `\"%E\"' not recognized", name);
5609 /* Get out of the current language scope. */
5612 pop_lang_context (void)
5614 current_lang_name = VARRAY_TOP_TREE (current_lang_base);
5615 VARRAY_POP (current_lang_base);
5618 /* Type instantiation routines. */
5620 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
5621 matches the TARGET_TYPE. If there is no satisfactory match, return
5622 error_mark_node, and issue a error & warning messages under control
5623 of FLAGS. Permit pointers to member function if FLAGS permits. If
5624 TEMPLATE_ONLY, the name of the overloaded function was a
5625 template-id, and EXPLICIT_TARGS are the explicitly provided
5626 template arguments. */
5629 resolve_address_of_overloaded_function (tree target_type,
5631 tsubst_flags_t flags,
5633 tree explicit_targs)
5635 /* Here's what the standard says:
5639 If the name is a function template, template argument deduction
5640 is done, and if the argument deduction succeeds, the deduced
5641 arguments are used to generate a single template function, which
5642 is added to the set of overloaded functions considered.
5644 Non-member functions and static member functions match targets of
5645 type "pointer-to-function" or "reference-to-function." Nonstatic
5646 member functions match targets of type "pointer-to-member
5647 function;" the function type of the pointer to member is used to
5648 select the member function from the set of overloaded member
5649 functions. If a nonstatic member function is selected, the
5650 reference to the overloaded function name is required to have the
5651 form of a pointer to member as described in 5.3.1.
5653 If more than one function is selected, any template functions in
5654 the set are eliminated if the set also contains a non-template
5655 function, and any given template function is eliminated if the
5656 set contains a second template function that is more specialized
5657 than the first according to the partial ordering rules 14.5.5.2.
5658 After such eliminations, if any, there shall remain exactly one
5659 selected function. */
5662 int is_reference = 0;
5663 /* We store the matches in a TREE_LIST rooted here. The functions
5664 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
5665 interoperability with most_specialized_instantiation. */
5666 tree matches = NULL_TREE;
5669 /* By the time we get here, we should be seeing only real
5670 pointer-to-member types, not the internal POINTER_TYPE to
5671 METHOD_TYPE representation. */
5672 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
5673 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
5675 gcc_assert (is_overloaded_fn (overload));
5677 /* Check that the TARGET_TYPE is reasonable. */
5678 if (TYPE_PTRFN_P (target_type))
5680 else if (TYPE_PTRMEMFUNC_P (target_type))
5681 /* This is OK, too. */
5683 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
5685 /* This is OK, too. This comes from a conversion to reference
5687 target_type = build_reference_type (target_type);
5692 if (flags & tf_error)
5694 cannot resolve overloaded function `%D' based on conversion to type `%T'",
5695 DECL_NAME (OVL_FUNCTION (overload)), target_type);
5696 return error_mark_node;
5699 /* If we can find a non-template function that matches, we can just
5700 use it. There's no point in generating template instantiations
5701 if we're just going to throw them out anyhow. But, of course, we
5702 can only do this when we don't *need* a template function. */
5707 for (fns = overload; fns; fns = OVL_NEXT (fns))
5709 tree fn = OVL_CURRENT (fns);
5712 if (TREE_CODE (fn) == TEMPLATE_DECL)
5713 /* We're not looking for templates just yet. */
5716 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5718 /* We're looking for a non-static member, and this isn't
5719 one, or vice versa. */
5722 /* Ignore anticipated decls of undeclared builtins. */
5723 if (DECL_ANTICIPATED (fn))
5726 /* See if there's a match. */
5727 fntype = TREE_TYPE (fn);
5729 fntype = build_ptrmemfunc_type (build_pointer_type (fntype));
5730 else if (!is_reference)
5731 fntype = build_pointer_type (fntype);
5733 if (can_convert_arg (target_type, fntype, fn))
5734 matches = tree_cons (fn, NULL_TREE, matches);
5738 /* Now, if we've already got a match (or matches), there's no need
5739 to proceed to the template functions. But, if we don't have a
5740 match we need to look at them, too. */
5743 tree target_fn_type;
5744 tree target_arg_types;
5745 tree target_ret_type;
5750 = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (target_type));
5752 target_fn_type = TREE_TYPE (target_type);
5753 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
5754 target_ret_type = TREE_TYPE (target_fn_type);
5756 /* Never do unification on the 'this' parameter. */
5757 if (TREE_CODE (target_fn_type) == METHOD_TYPE)
5758 target_arg_types = TREE_CHAIN (target_arg_types);
5760 for (fns = overload; fns; fns = OVL_NEXT (fns))
5762 tree fn = OVL_CURRENT (fns);
5764 tree instantiation_type;
5767 if (TREE_CODE (fn) != TEMPLATE_DECL)
5768 /* We're only looking for templates. */
5771 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5773 /* We're not looking for a non-static member, and this is
5774 one, or vice versa. */
5777 /* Try to do argument deduction. */
5778 targs = make_tree_vec (DECL_NTPARMS (fn));
5779 if (fn_type_unification (fn, explicit_targs, targs,
5780 target_arg_types, target_ret_type,
5781 DEDUCE_EXACT, -1) != 0)
5782 /* Argument deduction failed. */
5785 /* Instantiate the template. */
5786 instantiation = instantiate_template (fn, targs, flags);
5787 if (instantiation == error_mark_node)
5788 /* Instantiation failed. */
5791 /* See if there's a match. */
5792 instantiation_type = TREE_TYPE (instantiation);
5794 instantiation_type =
5795 build_ptrmemfunc_type (build_pointer_type (instantiation_type));
5796 else if (!is_reference)
5797 instantiation_type = build_pointer_type (instantiation_type);
5798 if (can_convert_arg (target_type, instantiation_type, instantiation))
5799 matches = tree_cons (instantiation, fn, matches);
5802 /* Now, remove all but the most specialized of the matches. */
5805 tree match = most_specialized_instantiation (matches);
5807 if (match != error_mark_node)
5808 matches = tree_cons (match, NULL_TREE, NULL_TREE);
5812 /* Now we should have exactly one function in MATCHES. */
5813 if (matches == NULL_TREE)
5815 /* There were *no* matches. */
5816 if (flags & tf_error)
5818 error ("no matches converting function `%D' to type `%#T'",
5819 DECL_NAME (OVL_FUNCTION (overload)),
5822 /* print_candidates expects a chain with the functions in
5823 TREE_VALUE slots, so we cons one up here (we're losing anyway,
5824 so why be clever?). */
5825 for (; overload; overload = OVL_NEXT (overload))
5826 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
5829 print_candidates (matches);
5831 return error_mark_node;
5833 else if (TREE_CHAIN (matches))
5835 /* There were too many matches. */
5837 if (flags & tf_error)
5841 error ("converting overloaded function `%D' to type `%#T' is ambiguous",
5842 DECL_NAME (OVL_FUNCTION (overload)),
5845 /* Since print_candidates expects the functions in the
5846 TREE_VALUE slot, we flip them here. */
5847 for (match = matches; match; match = TREE_CHAIN (match))
5848 TREE_VALUE (match) = TREE_PURPOSE (match);
5850 print_candidates (matches);
5853 return error_mark_node;
5856 /* Good, exactly one match. Now, convert it to the correct type. */
5857 fn = TREE_PURPOSE (matches);
5859 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
5860 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
5862 static int explained;
5864 if (!(flags & tf_error))
5865 return error_mark_node;
5867 pedwarn ("assuming pointer to member `%D'", fn);
5870 pedwarn ("(a pointer to member can only be formed with `&%E')", fn);
5875 /* If we're doing overload resolution purely for the purpose of
5876 determining conversion sequences, we should not consider the
5877 function used. If this conversion sequence is selected, the
5878 function will be marked as used at this point. */
5879 if (!(flags & tf_conv))
5882 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
5883 return build_unary_op (ADDR_EXPR, fn, 0);
5886 /* The target must be a REFERENCE_TYPE. Above, build_unary_op
5887 will mark the function as addressed, but here we must do it
5889 cxx_mark_addressable (fn);
5895 /* This function will instantiate the type of the expression given in
5896 RHS to match the type of LHSTYPE. If errors exist, then return
5897 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
5898 we complain on errors. If we are not complaining, never modify rhs,
5899 as overload resolution wants to try many possible instantiations, in
5900 the hope that at least one will work.
5902 For non-recursive calls, LHSTYPE should be a function, pointer to
5903 function, or a pointer to member function. */
5906 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
5908 tsubst_flags_t flags_in = flags;
5910 flags &= ~tf_ptrmem_ok;
5912 if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
5914 if (flags & tf_error)
5915 error ("not enough type information");
5916 return error_mark_node;
5919 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
5921 if (same_type_p (lhstype, TREE_TYPE (rhs)))
5923 if (flag_ms_extensions
5924 && TYPE_PTRMEMFUNC_P (lhstype)
5925 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
5926 /* Microsoft allows `A::f' to be resolved to a
5927 pointer-to-member. */
5931 if (flags & tf_error)
5932 error ("argument of type `%T' does not match `%T'",
5933 TREE_TYPE (rhs), lhstype);
5934 return error_mark_node;
5938 if (TREE_CODE (rhs) == BASELINK)
5939 rhs = BASELINK_FUNCTIONS (rhs);
5941 /* We don't overwrite rhs if it is an overloaded function.
5942 Copying it would destroy the tree link. */
5943 if (TREE_CODE (rhs) != OVERLOAD)
5944 rhs = copy_node (rhs);
5946 /* This should really only be used when attempting to distinguish
5947 what sort of a pointer to function we have. For now, any
5948 arithmetic operation which is not supported on pointers
5949 is rejected as an error. */
5951 switch (TREE_CODE (rhs))
5964 new_rhs = instantiate_type (build_pointer_type (lhstype),
5965 TREE_OPERAND (rhs, 0), flags);
5966 if (new_rhs == error_mark_node)
5967 return error_mark_node;
5969 TREE_TYPE (rhs) = lhstype;
5970 TREE_OPERAND (rhs, 0) = new_rhs;
5975 rhs = copy_node (TREE_OPERAND (rhs, 0));
5976 TREE_TYPE (rhs) = unknown_type_node;
5977 return instantiate_type (lhstype, rhs, flags);
5981 tree addr = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags);
5983 if (addr != error_mark_node
5984 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
5985 /* Do not lose object's side effects. */
5986 addr = build2 (COMPOUND_EXPR, TREE_TYPE (addr),
5987 TREE_OPERAND (rhs, 0), addr);
5992 rhs = TREE_OPERAND (rhs, 1);
5993 if (BASELINK_P (rhs))
5994 return instantiate_type (lhstype, BASELINK_FUNCTIONS (rhs), flags_in);
5996 /* This can happen if we are forming a pointer-to-member for a
5998 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6002 case TEMPLATE_ID_EXPR:
6004 tree fns = TREE_OPERAND (rhs, 0);
6005 tree args = TREE_OPERAND (rhs, 1);
6008 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6009 /*template_only=*/true,
6016 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6017 /*template_only=*/false,
6018 /*explicit_targs=*/NULL_TREE);
6021 /* Now we should have a baselink. */
6022 gcc_assert (BASELINK_P (rhs));
6024 return instantiate_type (lhstype, BASELINK_FUNCTIONS (rhs), flags);
6027 /* This is too hard for now. */
6033 TREE_OPERAND (rhs, 0)
6034 = instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6035 if (TREE_OPERAND (rhs, 0) == error_mark_node)
6036 return error_mark_node;
6037 TREE_OPERAND (rhs, 1)
6038 = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags);
6039 if (TREE_OPERAND (rhs, 1) == error_mark_node)
6040 return error_mark_node;
6042 TREE_TYPE (rhs) = lhstype;
6046 case TRUNC_DIV_EXPR:
6047 case FLOOR_DIV_EXPR:
6049 case ROUND_DIV_EXPR:
6051 case TRUNC_MOD_EXPR:
6052 case FLOOR_MOD_EXPR:
6054 case ROUND_MOD_EXPR:
6055 case FIX_ROUND_EXPR:
6056 case FIX_FLOOR_EXPR:
6058 case FIX_TRUNC_EXPR:
6073 case PREINCREMENT_EXPR:
6074 case PREDECREMENT_EXPR:
6075 case POSTINCREMENT_EXPR:
6076 case POSTDECREMENT_EXPR:
6077 if (flags & tf_error)
6078 error ("invalid operation on uninstantiated type");
6079 return error_mark_node;
6081 case TRUTH_AND_EXPR:
6083 case TRUTH_XOR_EXPR:
6090 case TRUTH_ANDIF_EXPR:
6091 case TRUTH_ORIF_EXPR:
6092 case TRUTH_NOT_EXPR:
6093 if (flags & tf_error)
6094 error ("not enough type information");
6095 return error_mark_node;
6098 if (type_unknown_p (TREE_OPERAND (rhs, 0)))
6100 if (flags & tf_error)
6101 error ("not enough type information");
6102 return error_mark_node;
6104 TREE_OPERAND (rhs, 1)
6105 = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags);
6106 if (TREE_OPERAND (rhs, 1) == error_mark_node)
6107 return error_mark_node;
6108 TREE_OPERAND (rhs, 2)
6109 = instantiate_type (lhstype, TREE_OPERAND (rhs, 2), flags);
6110 if (TREE_OPERAND (rhs, 2) == error_mark_node)
6111 return error_mark_node;
6113 TREE_TYPE (rhs) = lhstype;
6117 TREE_OPERAND (rhs, 1)
6118 = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags);
6119 if (TREE_OPERAND (rhs, 1) == error_mark_node)
6120 return error_mark_node;
6122 TREE_TYPE (rhs) = lhstype;
6127 if (PTRMEM_OK_P (rhs))
6128 flags |= tf_ptrmem_ok;
6130 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6134 return error_mark_node;
6139 return error_mark_node;
6142 /* Return the name of the virtual function pointer field
6143 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6144 this may have to look back through base types to find the
6145 ultimate field name. (For single inheritance, these could
6146 all be the same name. Who knows for multiple inheritance). */
6149 get_vfield_name (tree type)
6151 tree binfo, base_binfo;
6154 for (binfo = TYPE_BINFO (type);
6155 BINFO_N_BASE_BINFOS (binfo);
6158 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6160 if (BINFO_VIRTUAL_P (base_binfo)
6161 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6165 type = BINFO_TYPE (binfo);
6166 buf = alloca (sizeof (VFIELD_NAME_FORMAT) + TYPE_NAME_LENGTH (type) + 2);
6167 sprintf (buf, VFIELD_NAME_FORMAT,
6168 IDENTIFIER_POINTER (constructor_name (type)));
6169 return get_identifier (buf);
6173 print_class_statistics (void)
6175 #ifdef GATHER_STATISTICS
6176 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6177 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6180 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6181 n_vtables, n_vtable_searches);
6182 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6183 n_vtable_entries, n_vtable_elems);
6188 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6189 according to [class]:
6190 The class-name is also inserted
6191 into the scope of the class itself. For purposes of access checking,
6192 the inserted class name is treated as if it were a public member name. */
6195 build_self_reference (void)
6197 tree name = constructor_name (current_class_type);
6198 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6201 DECL_NONLOCAL (value) = 1;
6202 DECL_CONTEXT (value) = current_class_type;
6203 DECL_ARTIFICIAL (value) = 1;
6204 SET_DECL_SELF_REFERENCE_P (value);
6206 if (processing_template_decl)
6207 value = push_template_decl (value);
6209 saved_cas = current_access_specifier;
6210 current_access_specifier = access_public_node;
6211 finish_member_declaration (value);
6212 current_access_specifier = saved_cas;
6215 /* Returns 1 if TYPE contains only padding bytes. */
6218 is_empty_class (tree type)
6220 if (type == error_mark_node)
6223 if (! IS_AGGR_TYPE (type))
6226 /* In G++ 3.2, whether or not a class was empty was determined by
6227 looking at its size. */
6228 if (abi_version_at_least (2))
6229 return CLASSTYPE_EMPTY_P (type);
6231 return integer_zerop (CLASSTYPE_SIZE (type));
6234 /* Returns true if TYPE contains an empty class. */
6237 contains_empty_class_p (tree type)
6239 if (is_empty_class (type))
6241 if (CLASS_TYPE_P (type))
6248 for (binfo = TYPE_BINFO (type), i = 0;
6249 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6250 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6252 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6253 if (TREE_CODE (field) == FIELD_DECL
6254 && !DECL_ARTIFICIAL (field)
6255 && is_empty_class (TREE_TYPE (field)))
6258 else if (TREE_CODE (type) == ARRAY_TYPE)
6259 return contains_empty_class_p (TREE_TYPE (type));
6263 /* Find the enclosing class of the given NODE. NODE can be a *_DECL or
6264 a *_TYPE node. NODE can also be a local class. */
6267 get_enclosing_class (tree type)
6271 while (node && TREE_CODE (node) != NAMESPACE_DECL)
6273 switch (TREE_CODE_CLASS (TREE_CODE (node)))
6276 node = DECL_CONTEXT (node);
6282 node = TYPE_CONTEXT (node);
6292 /* Note that NAME was looked up while the current class was being
6293 defined and that the result of that lookup was DECL. */
6296 maybe_note_name_used_in_class (tree name, tree decl)
6298 splay_tree names_used;
6300 /* If we're not defining a class, there's nothing to do. */
6301 if (!(innermost_scope_kind() == sk_class
6302 && TYPE_BEING_DEFINED (current_class_type)))
6305 /* If there's already a binding for this NAME, then we don't have
6306 anything to worry about. */
6307 if (lookup_member (current_class_type, name,
6308 /*protect=*/0, /*want_type=*/false))
6311 if (!current_class_stack[current_class_depth - 1].names_used)
6312 current_class_stack[current_class_depth - 1].names_used
6313 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6314 names_used = current_class_stack[current_class_depth - 1].names_used;
6316 splay_tree_insert (names_used,
6317 (splay_tree_key) name,
6318 (splay_tree_value) decl);
6321 /* Note that NAME was declared (as DECL) in the current class. Check
6322 to see that the declaration is valid. */
6325 note_name_declared_in_class (tree name, tree decl)
6327 splay_tree names_used;
6330 /* Look to see if we ever used this name. */
6332 = current_class_stack[current_class_depth - 1].names_used;
6336 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6339 /* [basic.scope.class]
6341 A name N used in a class S shall refer to the same declaration
6342 in its context and when re-evaluated in the completed scope of
6344 error ("declaration of `%#D'", decl);
6345 cp_error_at ("changes meaning of `%D' from `%+#D'",
6346 DECL_NAME (OVL_CURRENT (decl)),
6351 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6352 Secondary vtables are merged with primary vtables; this function
6353 will return the VAR_DECL for the primary vtable. */
6356 get_vtbl_decl_for_binfo (tree binfo)
6360 decl = BINFO_VTABLE (binfo);
6361 if (decl && TREE_CODE (decl) == PLUS_EXPR)
6363 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6364 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6367 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6372 /* Returns the binfo for the primary base of BINFO. If the resulting
6373 BINFO is a virtual base, and it is inherited elsewhere in the
6374 hierarchy, then the returned binfo might not be the primary base of
6375 BINFO in the complete object. Check BINFO_PRIMARY_P or
6376 BINFO_LOST_PRIMARY_P to be sure. */
6379 get_primary_binfo (tree binfo)
6384 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6388 result = copied_binfo (primary_base, binfo);
6392 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6395 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6398 fprintf (stream, "%*s", indent, "");
6402 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6403 INDENT should be zero when called from the top level; it is
6404 incremented recursively. IGO indicates the next expected BINFO in
6405 inheritance graph ordering. */
6408 dump_class_hierarchy_r (FILE *stream,
6418 indented = maybe_indent_hierarchy (stream, indent, 0);
6419 fprintf (stream, "%s (0x%lx) ",
6420 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6421 (unsigned long) binfo);
6424 fprintf (stream, "alternative-path\n");
6427 igo = TREE_CHAIN (binfo);
6429 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6430 tree_low_cst (BINFO_OFFSET (binfo), 0));
6431 if (is_empty_class (BINFO_TYPE (binfo)))
6432 fprintf (stream, " empty");
6433 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6434 fprintf (stream, " nearly-empty");
6435 if (BINFO_VIRTUAL_P (binfo))
6436 fprintf (stream, " virtual");
6437 fprintf (stream, "\n");
6440 if (BINFO_PRIMARY_P (binfo))
6442 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6443 fprintf (stream, " primary-for %s (0x%lx)",
6444 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6445 TFF_PLAIN_IDENTIFIER),
6446 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6448 if (BINFO_LOST_PRIMARY_P (binfo))
6450 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6451 fprintf (stream, " lost-primary");
6454 fprintf (stream, "\n");
6456 if (!(flags & TDF_SLIM))
6460 if (BINFO_SUBVTT_INDEX (binfo))
6462 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6463 fprintf (stream, " subvttidx=%s",
6464 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6465 TFF_PLAIN_IDENTIFIER));
6467 if (BINFO_VPTR_INDEX (binfo))
6469 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6470 fprintf (stream, " vptridx=%s",
6471 expr_as_string (BINFO_VPTR_INDEX (binfo),
6472 TFF_PLAIN_IDENTIFIER));
6474 if (BINFO_VPTR_FIELD (binfo))
6476 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6477 fprintf (stream, " vbaseoffset=%s",
6478 expr_as_string (BINFO_VPTR_FIELD (binfo),
6479 TFF_PLAIN_IDENTIFIER));
6481 if (BINFO_VTABLE (binfo))
6483 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6484 fprintf (stream, " vptr=%s",
6485 expr_as_string (BINFO_VTABLE (binfo),
6486 TFF_PLAIN_IDENTIFIER));
6490 fprintf (stream, "\n");
6493 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6494 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6499 /* Dump the BINFO hierarchy for T. */
6502 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6504 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6505 fprintf (stream, " size=%lu align=%lu\n",
6506 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6507 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6508 fprintf (stream, " base size=%lu base align=%lu\n",
6509 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6511 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6513 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6514 fprintf (stream, "\n");
6517 /* Debug interface to hierarchy dumping. */
6520 debug_class (tree t)
6522 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6526 dump_class_hierarchy (tree t)
6529 FILE *stream = dump_begin (TDI_class, &flags);
6533 dump_class_hierarchy_1 (stream, flags, t);
6534 dump_end (TDI_class, stream);
6539 dump_array (FILE * stream, tree decl)
6544 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6546 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6548 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6549 fprintf (stream, " %s entries",
6550 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6551 TFF_PLAIN_IDENTIFIER));
6552 fprintf (stream, "\n");
6554 for (ix = 0, inits = CONSTRUCTOR_ELTS (DECL_INITIAL (decl));
6555 inits; ix++, inits = TREE_CHAIN (inits))
6556 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
6557 expr_as_string (TREE_VALUE (inits), TFF_PLAIN_IDENTIFIER));
6561 dump_vtable (tree t, tree binfo, tree vtable)
6564 FILE *stream = dump_begin (TDI_class, &flags);
6569 if (!(flags & TDF_SLIM))
6571 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6573 fprintf (stream, "%s for %s",
6574 ctor_vtbl_p ? "Construction vtable" : "Vtable",
6575 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6578 if (!BINFO_VIRTUAL_P (binfo))
6579 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6580 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6582 fprintf (stream, "\n");
6583 dump_array (stream, vtable);
6584 fprintf (stream, "\n");
6587 dump_end (TDI_class, stream);
6591 dump_vtt (tree t, tree vtt)
6594 FILE *stream = dump_begin (TDI_class, &flags);
6599 if (!(flags & TDF_SLIM))
6601 fprintf (stream, "VTT for %s\n",
6602 type_as_string (t, TFF_PLAIN_IDENTIFIER));
6603 dump_array (stream, vtt);
6604 fprintf (stream, "\n");
6607 dump_end (TDI_class, stream);
6610 /* Dump a function or thunk and its thunkees. */
6613 dump_thunk (FILE *stream, int indent, tree thunk)
6615 static const char spaces[] = " ";
6616 tree name = DECL_NAME (thunk);
6619 fprintf (stream, "%.*s%p %s %s", indent, spaces,
6621 !DECL_THUNK_P (thunk) ? "function"
6622 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6623 name ? IDENTIFIER_POINTER (name) : "<unset>");
6624 if (DECL_THUNK_P (thunk))
6626 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6627 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6629 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6630 if (!virtual_adjust)
6632 else if (DECL_THIS_THUNK_P (thunk))
6633 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
6634 tree_low_cst (virtual_adjust, 0));
6636 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6637 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6638 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6639 if (THUNK_ALIAS (thunk))
6640 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6642 fprintf (stream, "\n");
6643 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6644 dump_thunk (stream, indent + 2, thunks);
6647 /* Dump the thunks for FN. */
6650 debug_thunks (tree fn)
6652 dump_thunk (stderr, 0, fn);
6655 /* Virtual function table initialization. */
6657 /* Create all the necessary vtables for T and its base classes. */
6660 finish_vtbls (tree t)
6665 /* We lay out the primary and secondary vtables in one contiguous
6666 vtable. The primary vtable is first, followed by the non-virtual
6667 secondary vtables in inheritance graph order. */
6668 list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6669 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6670 TYPE_BINFO (t), t, list);
6672 /* Then come the virtual bases, also in inheritance graph order. */
6673 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6675 if (!BINFO_VIRTUAL_P (vbase))
6677 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6680 if (BINFO_VTABLE (TYPE_BINFO (t)))
6681 initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
6684 /* Initialize the vtable for BINFO with the INITS. */
6687 initialize_vtable (tree binfo, tree inits)
6691 layout_vtable_decl (binfo, list_length (inits));
6692 decl = get_vtbl_decl_for_binfo (binfo);
6693 initialize_artificial_var (decl, inits);
6694 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
6697 /* Build the VTT (virtual table table) for T.
6698 A class requires a VTT if it has virtual bases.
6701 1 - primary virtual pointer for complete object T
6702 2 - secondary VTTs for each direct non-virtual base of T which requires a
6704 3 - secondary virtual pointers for each direct or indirect base of T which
6705 has virtual bases or is reachable via a virtual path from T.
6706 4 - secondary VTTs for each direct or indirect virtual base of T.
6708 Secondary VTTs look like complete object VTTs without part 4. */
6718 /* Build up the initializers for the VTT. */
6720 index = size_zero_node;
6721 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
6723 /* If we didn't need a VTT, we're done. */
6727 /* Figure out the type of the VTT. */
6728 type = build_index_type (size_int (list_length (inits) - 1));
6729 type = build_cplus_array_type (const_ptr_type_node, type);
6731 /* Now, build the VTT object itself. */
6732 vtt = build_vtable (t, get_vtt_name (t), type);
6733 initialize_artificial_var (vtt, inits);
6734 /* Add the VTT to the vtables list. */
6735 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
6736 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
6741 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
6742 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
6743 and CHAIN the vtable pointer for this binfo after construction is
6744 complete. VALUE can also be another BINFO, in which case we recurse. */
6747 binfo_ctor_vtable (tree binfo)
6753 vt = BINFO_VTABLE (binfo);
6754 if (TREE_CODE (vt) == TREE_LIST)
6755 vt = TREE_VALUE (vt);
6756 if (TREE_CODE (vt) == TREE_BINFO)
6765 /* Recursively build the VTT-initializer for BINFO (which is in the
6766 hierarchy dominated by T). INITS points to the end of the initializer
6767 list to date. INDEX is the VTT index where the next element will be
6768 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
6769 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
6770 for virtual bases of T. When it is not so, we build the constructor
6771 vtables for the BINFO-in-T variant. */
6774 build_vtt_inits (tree binfo, tree t, tree* inits, tree* index)
6779 tree secondary_vptrs;
6780 int top_level_p = same_type_p (TREE_TYPE (binfo), t);
6782 /* We only need VTTs for subobjects with virtual bases. */
6783 if (!TYPE_USES_VIRTUAL_BASECLASSES (BINFO_TYPE (binfo)))
6786 /* We need to use a construction vtable if this is not the primary
6790 build_ctor_vtbl_group (binfo, t);
6792 /* Record the offset in the VTT where this sub-VTT can be found. */
6793 BINFO_SUBVTT_INDEX (binfo) = *index;
6796 /* Add the address of the primary vtable for the complete object. */
6797 init = binfo_ctor_vtable (binfo);
6798 *inits = build_tree_list (NULL_TREE, init);
6799 inits = &TREE_CHAIN (*inits);
6802 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6803 BINFO_VPTR_INDEX (binfo) = *index;
6805 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
6807 /* Recursively add the secondary VTTs for non-virtual bases. */
6808 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
6809 if (!BINFO_VIRTUAL_P (b))
6810 inits = build_vtt_inits (BINFO_BASE_BINFO (binfo, i), t, inits, index);
6812 /* Add secondary virtual pointers for all subobjects of BINFO with
6813 either virtual bases or reachable along a virtual path, except
6814 subobjects that are non-virtual primary bases. */
6815 secondary_vptrs = tree_cons (t, NULL_TREE, BINFO_TYPE (binfo));
6816 TREE_TYPE (secondary_vptrs) = *index;
6817 VTT_TOP_LEVEL_P (secondary_vptrs) = top_level_p;
6818 VTT_MARKED_BINFO_P (secondary_vptrs) = 0;
6820 dfs_walk_real (binfo,
6821 dfs_build_secondary_vptr_vtt_inits,
6823 dfs_ctor_vtable_bases_queue_p,
6825 VTT_MARKED_BINFO_P (secondary_vptrs) = 1;
6826 dfs_walk (binfo, dfs_unmark, dfs_ctor_vtable_bases_queue_p,
6829 *index = TREE_TYPE (secondary_vptrs);
6831 /* The secondary vptrs come back in reverse order. After we reverse
6832 them, and add the INITS, the last init will be the first element
6834 secondary_vptrs = TREE_VALUE (secondary_vptrs);
6835 if (secondary_vptrs)
6837 *inits = nreverse (secondary_vptrs);
6838 inits = &TREE_CHAIN (secondary_vptrs);
6839 gcc_assert (*inits == NULL_TREE);
6842 /* Add the secondary VTTs for virtual bases. */
6844 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
6846 if (!BINFO_VIRTUAL_P (b))
6849 inits = build_vtt_inits (b, t, inits, index);
6854 tree data = tree_cons (t, binfo, NULL_TREE);
6855 VTT_TOP_LEVEL_P (data) = 0;
6856 VTT_MARKED_BINFO_P (data) = 0;
6858 dfs_walk (binfo, dfs_fixup_binfo_vtbls,
6859 dfs_ctor_vtable_bases_queue_p,
6866 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
6867 in most derived. DATA is a TREE_LIST who's TREE_CHAIN is the type of the
6868 base being constructed whilst this secondary vptr is live. The
6869 TREE_TOP_LEVEL flag indicates that this is the primary VTT. */
6872 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data)
6882 top_level_p = VTT_TOP_LEVEL_P (l);
6884 BINFO_MARKED (binfo) = 1;
6886 /* We don't care about bases that don't have vtables. */
6887 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
6890 /* We're only interested in proper subobjects of T. */
6891 if (same_type_p (BINFO_TYPE (binfo), t))
6894 /* We're not interested in non-virtual primary bases. */
6895 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
6898 /* If BINFO has virtual bases or is reachable via a virtual path
6899 from T, it'll have a secondary vptr. */
6900 if (!TYPE_USES_VIRTUAL_BASECLASSES (BINFO_TYPE (binfo))
6901 && !binfo_via_virtual (binfo, t))
6904 /* Record the index where this secondary vptr can be found. */
6905 index = TREE_TYPE (l);
6908 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6909 BINFO_VPTR_INDEX (binfo) = index;
6911 TREE_TYPE (l) = size_binop (PLUS_EXPR, index,
6912 TYPE_SIZE_UNIT (ptr_type_node));
6914 /* Add the initializer for the secondary vptr itself. */
6915 if (top_level_p && BINFO_VIRTUAL_P (binfo))
6917 /* It's a primary virtual base, and this is not the construction
6918 vtable. Find the base this is primary of in the inheritance graph,
6919 and use that base's vtable now. */
6920 while (BINFO_PRIMARY_P (binfo))
6921 binfo = BINFO_INHERITANCE_CHAIN (binfo);
6923 init = binfo_ctor_vtable (binfo);
6924 TREE_VALUE (l) = tree_cons (NULL_TREE, init, TREE_VALUE (l));
6929 /* dfs_walk_real predicate for building vtables. DATA is a TREE_LIST,
6930 VTT_MARKED_BINFO_P indicates whether marked or unmarked bases
6931 should be walked. TREE_PURPOSE is the TREE_TYPE that dominates the
6935 dfs_ctor_vtable_bases_queue_p (tree derived, int ix,
6938 tree binfo = BINFO_BASE_BINFO (derived, ix);
6940 if (!BINFO_MARKED (binfo) == VTT_MARKED_BINFO_P ((tree) data))
6945 /* Called from build_vtt_inits via dfs_walk. After building constructor
6946 vtables and generating the sub-vtt from them, we need to restore the
6947 BINFO_VTABLES that were scribbled on. DATA is a TREE_LIST whose
6948 TREE_VALUE is the TREE_TYPE of the base whose sub vtt was generated. */
6951 dfs_fixup_binfo_vtbls (tree binfo, void* data)
6953 BINFO_MARKED (binfo) = 0;
6955 /* We don't care about bases that don't have vtables. */
6956 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
6959 /* If we scribbled the construction vtable vptr into BINFO, clear it
6961 if (BINFO_VTABLE (binfo)
6962 && TREE_CODE (BINFO_VTABLE (binfo)) == TREE_LIST
6963 && (TREE_PURPOSE (BINFO_VTABLE (binfo))
6964 == TREE_VALUE ((tree) data)))
6965 BINFO_VTABLE (binfo) = TREE_CHAIN (BINFO_VTABLE (binfo));
6970 /* Build the construction vtable group for BINFO which is in the
6971 hierarchy dominated by T. */
6974 build_ctor_vtbl_group (tree binfo, tree t)
6983 /* See if we've already created this construction vtable group. */
6984 id = mangle_ctor_vtbl_for_type (t, binfo);
6985 if (IDENTIFIER_GLOBAL_VALUE (id))
6988 gcc_assert (!same_type_p (BINFO_TYPE (binfo), t));
6989 /* Build a version of VTBL (with the wrong type) for use in
6990 constructing the addresses of secondary vtables in the
6991 construction vtable group. */
6992 vtbl = build_vtable (t, id, ptr_type_node);
6993 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
6994 list = build_tree_list (vtbl, NULL_TREE);
6995 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
6998 /* Add the vtables for each of our virtual bases using the vbase in T
7000 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7002 vbase = TREE_CHAIN (vbase))
7006 if (!BINFO_VIRTUAL_P (vbase))
7008 b = copied_binfo (vbase, binfo);
7010 accumulate_vtbl_inits (b, vbase, binfo, t, list);
7012 inits = TREE_VALUE (list);
7014 /* Figure out the type of the construction vtable. */
7015 type = build_index_type (size_int (list_length (inits) - 1));
7016 type = build_cplus_array_type (vtable_entry_type, type);
7017 TREE_TYPE (vtbl) = type;
7019 /* Initialize the construction vtable. */
7020 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7021 initialize_artificial_var (vtbl, inits);
7022 dump_vtable (t, binfo, vtbl);
7025 /* Add the vtbl initializers for BINFO (and its bases other than
7026 non-virtual primaries) to the list of INITS. BINFO is in the
7027 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7028 the constructor the vtbl inits should be accumulated for. (If this
7029 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7030 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7031 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7032 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7033 but are not necessarily the same in terms of layout. */
7036 accumulate_vtbl_inits (tree binfo,
7044 int ctor_vtbl_p = !same_type_p (BINFO_TYPE (rtti_binfo), t);
7046 gcc_assert (same_type_p (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7048 /* If it doesn't have a vptr, we don't do anything. */
7049 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7052 /* If we're building a construction vtable, we're not interested in
7053 subobjects that don't require construction vtables. */
7055 && !TYPE_USES_VIRTUAL_BASECLASSES (BINFO_TYPE (binfo))
7056 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7059 /* Build the initializers for the BINFO-in-T vtable. */
7061 = chainon (TREE_VALUE (inits),
7062 dfs_accumulate_vtbl_inits (binfo, orig_binfo,
7063 rtti_binfo, t, inits));
7065 /* Walk the BINFO and its bases. We walk in preorder so that as we
7066 initialize each vtable we can figure out at what offset the
7067 secondary vtable lies from the primary vtable. We can't use
7068 dfs_walk here because we need to iterate through bases of BINFO
7069 and RTTI_BINFO simultaneously. */
7070 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7072 /* Skip virtual bases. */
7073 if (BINFO_VIRTUAL_P (base_binfo))
7075 accumulate_vtbl_inits (base_binfo,
7076 BINFO_BASE_BINFO (orig_binfo, i),
7082 /* Called from accumulate_vtbl_inits. Returns the initializers for
7083 the BINFO vtable. */
7086 dfs_accumulate_vtbl_inits (tree binfo,
7092 tree inits = NULL_TREE;
7093 tree vtbl = NULL_TREE;
7094 int ctor_vtbl_p = !same_type_p (BINFO_TYPE (rtti_binfo), t);
7097 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7099 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7100 primary virtual base. If it is not the same primary in
7101 the hierarchy of T, we'll need to generate a ctor vtable
7102 for it, to place at its location in T. If it is the same
7103 primary, we still need a VTT entry for the vtable, but it
7104 should point to the ctor vtable for the base it is a
7105 primary for within the sub-hierarchy of RTTI_BINFO.
7107 There are three possible cases:
7109 1) We are in the same place.
7110 2) We are a primary base within a lost primary virtual base of
7112 3) We are primary to something not a base of RTTI_BINFO. */
7115 tree last = NULL_TREE;
7117 /* First, look through the bases we are primary to for RTTI_BINFO
7118 or a virtual base. */
7120 while (BINFO_PRIMARY_P (b))
7122 b = BINFO_INHERITANCE_CHAIN (b);
7124 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7127 /* If we run out of primary links, keep looking down our
7128 inheritance chain; we might be an indirect primary. */
7129 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7130 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7134 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7135 base B and it is a base of RTTI_BINFO, this is case 2. In
7136 either case, we share our vtable with LAST, i.e. the
7137 derived-most base within B of which we are a primary. */
7139 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7140 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7141 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7142 binfo_ctor_vtable after everything's been set up. */
7145 /* Otherwise, this is case 3 and we get our own. */
7147 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7155 /* Compute the initializer for this vtable. */
7156 inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7159 /* Figure out the position to which the VPTR should point. */
7160 vtbl = TREE_PURPOSE (l);
7161 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7162 index = size_binop (PLUS_EXPR,
7163 size_int (non_fn_entries),
7164 size_int (list_length (TREE_VALUE (l))));
7165 index = size_binop (MULT_EXPR,
7166 TYPE_SIZE_UNIT (vtable_entry_type),
7168 vtbl = build2 (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7172 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7173 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7174 straighten this out. */
7175 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7176 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7179 /* For an ordinary vtable, set BINFO_VTABLE. */
7180 BINFO_VTABLE (binfo) = vtbl;
7185 /* Construct the initializer for BINFO's virtual function table. BINFO
7186 is part of the hierarchy dominated by T. If we're building a
7187 construction vtable, the ORIG_BINFO is the binfo we should use to
7188 find the actual function pointers to put in the vtable - but they
7189 can be overridden on the path to most-derived in the graph that
7190 ORIG_BINFO belongs. Otherwise,
7191 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7192 BINFO that should be indicated by the RTTI information in the
7193 vtable; it will be a base class of T, rather than T itself, if we
7194 are building a construction vtable.
7196 The value returned is a TREE_LIST suitable for wrapping in a
7197 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7198 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7199 number of non-function entries in the vtable.
7201 It might seem that this function should never be called with a
7202 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7203 base is always subsumed by a derived class vtable. However, when
7204 we are building construction vtables, we do build vtables for
7205 primary bases; we need these while the primary base is being
7209 build_vtbl_initializer (tree binfo,
7213 int* non_fn_entries_p)
7222 /* Initialize VID. */
7223 memset (&vid, 0, sizeof (vid));
7226 vid.rtti_binfo = rtti_binfo;
7227 vid.last_init = &vid.inits;
7228 vid.primary_vtbl_p = (binfo == TYPE_BINFO (t));
7229 vid.ctor_vtbl_p = !same_type_p (BINFO_TYPE (rtti_binfo), t);
7230 vid.generate_vcall_entries = true;
7231 /* The first vbase or vcall offset is at index -3 in the vtable. */
7232 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7234 /* Add entries to the vtable for RTTI. */
7235 build_rtti_vtbl_entries (binfo, &vid);
7237 /* Create an array for keeping track of the functions we've
7238 processed. When we see multiple functions with the same
7239 signature, we share the vcall offsets. */
7240 VARRAY_TREE_INIT (vid.fns, 32, "fns");
7241 /* Add the vcall and vbase offset entries. */
7242 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7244 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7245 build_vbase_offset_vtbl_entries. */
7246 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7247 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7248 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7250 /* If the target requires padding between data entries, add that now. */
7251 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7255 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7260 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7261 add = tree_cons (NULL_TREE,
7262 build1 (NOP_EXPR, vtable_entry_type,
7269 if (non_fn_entries_p)
7270 *non_fn_entries_p = list_length (vid.inits);
7272 /* Go through all the ordinary virtual functions, building up
7274 vfun_inits = NULL_TREE;
7275 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7279 tree fn, fn_original;
7280 tree init = NULL_TREE;
7284 if (DECL_THUNK_P (fn))
7286 if (!DECL_NAME (fn))
7288 if (THUNK_ALIAS (fn))
7290 fn = THUNK_ALIAS (fn);
7293 fn_original = THUNK_TARGET (fn);
7296 /* If the only definition of this function signature along our
7297 primary base chain is from a lost primary, this vtable slot will
7298 never be used, so just zero it out. This is important to avoid
7299 requiring extra thunks which cannot be generated with the function.
7301 We first check this in update_vtable_entry_for_fn, so we handle
7302 restored primary bases properly; we also need to do it here so we
7303 zero out unused slots in ctor vtables, rather than filling themff
7304 with erroneous values (though harmless, apart from relocation
7306 for (b = binfo; ; b = get_primary_binfo (b))
7308 /* We found a defn before a lost primary; go ahead as normal. */
7309 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7312 /* The nearest definition is from a lost primary; clear the
7314 if (BINFO_LOST_PRIMARY_P (b))
7316 init = size_zero_node;
7323 /* Pull the offset for `this', and the function to call, out of
7325 delta = BV_DELTA (v);
7326 vcall_index = BV_VCALL_INDEX (v);
7328 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7329 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7331 /* You can't call an abstract virtual function; it's abstract.
7332 So, we replace these functions with __pure_virtual. */
7333 if (DECL_PURE_VIRTUAL_P (fn_original))
7335 else if (!integer_zerop (delta) || vcall_index)
7337 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7338 if (!DECL_NAME (fn))
7341 /* Take the address of the function, considering it to be of an
7342 appropriate generic type. */
7343 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7346 /* And add it to the chain of initializers. */
7347 if (TARGET_VTABLE_USES_DESCRIPTORS)
7350 if (init == size_zero_node)
7351 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7352 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7354 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7356 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7357 TREE_OPERAND (init, 0),
7358 build_int_cst (NULL_TREE, i));
7359 TREE_CONSTANT (fdesc) = 1;
7360 TREE_INVARIANT (fdesc) = 1;
7362 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7366 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7369 /* The initializers for virtual functions were built up in reverse
7370 order; straighten them out now. */
7371 vfun_inits = nreverse (vfun_inits);
7373 /* The negative offset initializers are also in reverse order. */
7374 vid.inits = nreverse (vid.inits);
7376 /* Chain the two together. */
7377 return chainon (vid.inits, vfun_inits);
7380 /* Adds to vid->inits the initializers for the vbase and vcall
7381 offsets in BINFO, which is in the hierarchy dominated by T. */
7384 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7388 /* If this is a derived class, we must first create entries
7389 corresponding to the primary base class. */
7390 b = get_primary_binfo (binfo);
7392 build_vcall_and_vbase_vtbl_entries (b, vid);
7394 /* Add the vbase entries for this base. */
7395 build_vbase_offset_vtbl_entries (binfo, vid);
7396 /* Add the vcall entries for this base. */
7397 build_vcall_offset_vtbl_entries (binfo, vid);
7400 /* Returns the initializers for the vbase offset entries in the vtable
7401 for BINFO (which is part of the class hierarchy dominated by T), in
7402 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7403 where the next vbase offset will go. */
7406 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7410 tree non_primary_binfo;
7412 /* If there are no virtual baseclasses, then there is nothing to
7414 if (!TYPE_USES_VIRTUAL_BASECLASSES (BINFO_TYPE (binfo)))
7419 /* We might be a primary base class. Go up the inheritance hierarchy
7420 until we find the most derived class of which we are a primary base:
7421 it is the offset of that which we need to use. */
7422 non_primary_binfo = binfo;
7423 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7427 /* If we have reached a virtual base, then it must be a primary
7428 base (possibly multi-level) of vid->binfo, or we wouldn't
7429 have called build_vcall_and_vbase_vtbl_entries for it. But it
7430 might be a lost primary, so just skip down to vid->binfo. */
7431 if (BINFO_VIRTUAL_P (non_primary_binfo))
7433 non_primary_binfo = vid->binfo;
7437 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7438 if (get_primary_binfo (b) != non_primary_binfo)
7440 non_primary_binfo = b;
7443 /* Go through the virtual bases, adding the offsets. */
7444 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7446 vbase = TREE_CHAIN (vbase))
7451 if (!BINFO_VIRTUAL_P (vbase))
7454 /* Find the instance of this virtual base in the complete
7456 b = copied_binfo (vbase, binfo);
7458 /* If we've already got an offset for this virtual base, we
7459 don't need another one. */
7460 if (BINFO_VTABLE_PATH_MARKED (b))
7462 BINFO_VTABLE_PATH_MARKED (b) = 1;
7464 /* Figure out where we can find this vbase offset. */
7465 delta = size_binop (MULT_EXPR,
7468 TYPE_SIZE_UNIT (vtable_entry_type)));
7469 if (vid->primary_vtbl_p)
7470 BINFO_VPTR_FIELD (b) = delta;
7472 if (binfo != TYPE_BINFO (t))
7473 /* The vbase offset had better be the same. */
7474 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7476 /* The next vbase will come at a more negative offset. */
7477 vid->index = size_binop (MINUS_EXPR, vid->index,
7478 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7480 /* The initializer is the delta from BINFO to this virtual base.
7481 The vbase offsets go in reverse inheritance-graph order, and
7482 we are walking in inheritance graph order so these end up in
7484 delta = size_diffop (BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7487 = build_tree_list (NULL_TREE,
7488 fold (build1 (NOP_EXPR,
7491 vid->last_init = &TREE_CHAIN (*vid->last_init);
7495 /* Adds the initializers for the vcall offset entries in the vtable
7496 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7500 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7502 /* We only need these entries if this base is a virtual base. We
7503 compute the indices -- but do not add to the vtable -- when
7504 building the main vtable for a class. */
7505 if (BINFO_VIRTUAL_P (binfo) || binfo == TYPE_BINFO (vid->derived))
7507 /* We need a vcall offset for each of the virtual functions in this
7508 vtable. For example:
7510 class A { virtual void f (); };
7511 class B1 : virtual public A { virtual void f (); };
7512 class B2 : virtual public A { virtual void f (); };
7513 class C: public B1, public B2 { virtual void f (); };
7515 A C object has a primary base of B1, which has a primary base of A. A
7516 C also has a secondary base of B2, which no longer has a primary base
7517 of A. So the B2-in-C construction vtable needs a secondary vtable for
7518 A, which will adjust the A* to a B2* to call f. We have no way of
7519 knowing what (or even whether) this offset will be when we define B2,
7520 so we store this "vcall offset" in the A sub-vtable and look it up in
7521 a "virtual thunk" for B2::f.
7523 We need entries for all the functions in our primary vtable and
7524 in our non-virtual bases' secondary vtables. */
7526 /* If we are just computing the vcall indices -- but do not need
7527 the actual entries -- not that. */
7528 if (!BINFO_VIRTUAL_P (binfo))
7529 vid->generate_vcall_entries = false;
7530 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7531 add_vcall_offset_vtbl_entries_r (binfo, vid);
7535 /* Build vcall offsets, starting with those for BINFO. */
7538 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7544 /* Don't walk into virtual bases -- except, of course, for the
7545 virtual base for which we are building vcall offsets. Any
7546 primary virtual base will have already had its offsets generated
7547 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7548 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7551 /* If BINFO has a primary base, process it first. */
7552 primary_binfo = get_primary_binfo (binfo);
7554 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7556 /* Add BINFO itself to the list. */
7557 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7559 /* Scan the non-primary bases of BINFO. */
7560 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7561 if (base_binfo != primary_binfo)
7562 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7565 /* Called from build_vcall_offset_vtbl_entries_r. */
7568 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7570 /* Make entries for the rest of the virtuals. */
7571 if (abi_version_at_least (2))
7575 /* The ABI requires that the methods be processed in declaration
7576 order. G++ 3.2 used the order in the vtable. */
7577 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7579 orig_fn = TREE_CHAIN (orig_fn))
7580 if (DECL_VINDEX (orig_fn))
7581 add_vcall_offset (orig_fn, binfo, vid);
7585 tree derived_virtuals;
7588 /* If BINFO is a primary base, the most derived class which has
7589 BINFO as a primary base; otherwise, just BINFO. */
7590 tree non_primary_binfo;
7592 /* We might be a primary base class. Go up the inheritance hierarchy
7593 until we find the most derived class of which we are a primary base:
7594 it is the BINFO_VIRTUALS there that we need to consider. */
7595 non_primary_binfo = binfo;
7596 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7600 /* If we have reached a virtual base, then it must be vid->vbase,
7601 because we ignore other virtual bases in
7602 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7603 base (possibly multi-level) of vid->binfo, or we wouldn't
7604 have called build_vcall_and_vbase_vtbl_entries for it. But it
7605 might be a lost primary, so just skip down to vid->binfo. */
7606 if (BINFO_VIRTUAL_P (non_primary_binfo))
7608 gcc_assert (non_primary_binfo == vid->vbase);
7609 non_primary_binfo = vid->binfo;
7613 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7614 if (get_primary_binfo (b) != non_primary_binfo)
7616 non_primary_binfo = b;
7619 if (vid->ctor_vtbl_p)
7620 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7621 where rtti_binfo is the most derived type. */
7623 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7625 for (base_virtuals = BINFO_VIRTUALS (binfo),
7626 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7627 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7629 base_virtuals = TREE_CHAIN (base_virtuals),
7630 derived_virtuals = TREE_CHAIN (derived_virtuals),
7631 orig_virtuals = TREE_CHAIN (orig_virtuals))
7635 /* Find the declaration that originally caused this function to
7636 be present in BINFO_TYPE (binfo). */
7637 orig_fn = BV_FN (orig_virtuals);
7639 /* When processing BINFO, we only want to generate vcall slots for
7640 function slots introduced in BINFO. So don't try to generate
7641 one if the function isn't even defined in BINFO. */
7642 if (!same_type_p (DECL_CONTEXT (orig_fn), BINFO_TYPE (binfo)))
7645 add_vcall_offset (orig_fn, binfo, vid);
7650 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7653 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7658 /* If there is already an entry for a function with the same
7659 signature as FN, then we do not need a second vcall offset.
7660 Check the list of functions already present in the derived
7662 for (i = 0; i < VARRAY_ACTIVE_SIZE (vid->fns); ++i)
7666 derived_entry = VARRAY_TREE (vid->fns, i);
7667 if (same_signature_p (derived_entry, orig_fn)
7668 /* We only use one vcall offset for virtual destructors,
7669 even though there are two virtual table entries. */
7670 || (DECL_DESTRUCTOR_P (derived_entry)
7671 && DECL_DESTRUCTOR_P (orig_fn)))
7675 /* If we are building these vcall offsets as part of building
7676 the vtable for the most derived class, remember the vcall
7678 if (vid->binfo == TYPE_BINFO (vid->derived))
7680 tree_pair_p elt = VEC_safe_push (tree_pair_s,
7681 CLASSTYPE_VCALL_INDICES (vid->derived),
7683 elt->purpose = orig_fn;
7684 elt->value = vid->index;
7687 /* The next vcall offset will be found at a more negative
7689 vid->index = size_binop (MINUS_EXPR, vid->index,
7690 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7692 /* Keep track of this function. */
7693 VARRAY_PUSH_TREE (vid->fns, orig_fn);
7695 if (vid->generate_vcall_entries)
7700 /* Find the overriding function. */
7701 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
7702 if (fn == error_mark_node)
7703 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
7707 base = TREE_VALUE (fn);
7709 /* The vbase we're working on is a primary base of
7710 vid->binfo. But it might be a lost primary, so its
7711 BINFO_OFFSET might be wrong, so we just use the
7712 BINFO_OFFSET from vid->binfo. */
7713 vcall_offset = size_diffop (BINFO_OFFSET (base),
7714 BINFO_OFFSET (vid->binfo));
7715 vcall_offset = fold (build1 (NOP_EXPR, vtable_entry_type,
7718 /* Add the initializer to the vtable. */
7719 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
7720 vid->last_init = &TREE_CHAIN (*vid->last_init);
7724 /* Return vtbl initializers for the RTTI entries corresponding to the
7725 BINFO's vtable. The RTTI entries should indicate the object given
7726 by VID->rtti_binfo. */
7729 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
7738 basetype = BINFO_TYPE (binfo);
7739 t = BINFO_TYPE (vid->rtti_binfo);
7741 /* To find the complete object, we will first convert to our most
7742 primary base, and then add the offset in the vtbl to that value. */
7744 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
7745 && !BINFO_LOST_PRIMARY_P (b))
7749 primary_base = get_primary_binfo (b);
7750 gcc_assert (BINFO_PRIMARY_P (primary_base)
7751 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
7754 offset = size_diffop (BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
7756 /* The second entry is the address of the typeinfo object. */
7758 decl = build_address (get_tinfo_decl (t));
7760 decl = integer_zero_node;
7762 /* Convert the declaration to a type that can be stored in the
7764 init = build_nop (vfunc_ptr_type_node, decl);
7765 *vid->last_init = build_tree_list (NULL_TREE, init);
7766 vid->last_init = &TREE_CHAIN (*vid->last_init);
7768 /* Add the offset-to-top entry. It comes earlier in the vtable that
7769 the the typeinfo entry. Convert the offset to look like a
7770 function pointer, so that we can put it in the vtable. */
7771 init = build_nop (vfunc_ptr_type_node, offset);
7772 *vid->last_init = build_tree_list (NULL_TREE, init);
7773 vid->last_init = &TREE_CHAIN (*vid->last_init);
7776 /* Fold a OBJ_TYPE_REF expression to the address of a function.
7777 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
7780 cp_fold_obj_type_ref (tree ref, tree known_type)
7782 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
7783 HOST_WIDE_INT i = 0;
7784 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
7789 i += (TARGET_VTABLE_USES_DESCRIPTORS
7790 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
7796 #ifdef ENABLE_CHECKING
7797 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
7798 DECL_VINDEX (fndecl)));
7801 return build_address (fndecl);