1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, USA. */
25 /* High-level class interface. */
29 #include "coretypes.h"
40 #include "tree-dump.h"
42 /* The number of nested classes being processed. If we are not in the
43 scope of any class, this is zero. */
45 int current_class_depth;
47 /* In order to deal with nested classes, we keep a stack of classes.
48 The topmost entry is the innermost class, and is the entry at index
49 CURRENT_CLASS_DEPTH */
51 typedef struct class_stack_node {
52 /* The name of the class. */
55 /* The _TYPE node for the class. */
58 /* The access specifier pending for new declarations in the scope of
62 /* If were defining TYPE, the names used in this class. */
63 splay_tree names_used;
65 /* Nonzero if this class is no longer open, because of a call to
68 }* class_stack_node_t;
70 typedef struct vtbl_init_data_s
72 /* The base for which we're building initializers. */
74 /* The type of the most-derived type. */
76 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
77 unless ctor_vtbl_p is true. */
79 /* The negative-index vtable initializers built up so far. These
80 are in order from least negative index to most negative index. */
82 /* The last (i.e., most negative) entry in INITS. */
84 /* The binfo for the virtual base for which we're building
85 vcall offset initializers. */
87 /* The functions in vbase for which we have already provided vcall
90 /* The vtable index of the next vcall or vbase offset. */
92 /* Nonzero if we are building the initializer for the primary
95 /* Nonzero if we are building the initializer for a construction
98 /* True when adding vcall offset entries to the vtable. False when
99 merely computing the indices. */
100 bool generate_vcall_entries;
103 /* The type of a function passed to walk_subobject_offsets. */
104 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
106 /* The stack itself. This is a dynamically resized array. The
107 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
108 static int current_class_stack_size;
109 static class_stack_node_t current_class_stack;
111 /* The size of the largest empty class seen in this translation unit. */
112 static GTY (()) tree sizeof_biggest_empty_class;
114 /* An array of all local classes present in this translation unit, in
115 declaration order. */
116 VEC(tree,gc) *local_classes;
118 static tree get_vfield_name (tree);
119 static void finish_struct_anon (tree);
120 static tree get_vtable_name (tree);
121 static tree get_basefndecls (tree, tree);
122 static int build_primary_vtable (tree, tree);
123 static int build_secondary_vtable (tree);
124 static void finish_vtbls (tree);
125 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
126 static void finish_struct_bits (tree);
127 static int alter_access (tree, tree, tree);
128 static void handle_using_decl (tree, tree);
129 static tree dfs_modify_vtables (tree, void *);
130 static tree modify_all_vtables (tree, tree);
131 static void determine_primary_bases (tree);
132 static void finish_struct_methods (tree);
133 static void maybe_warn_about_overly_private_class (tree);
134 static int method_name_cmp (const void *, const void *);
135 static int resort_method_name_cmp (const void *, const void *);
136 static void add_implicitly_declared_members (tree, int, int);
137 static tree fixed_type_or_null (tree, int *, int *);
138 static tree build_simple_base_path (tree expr, tree binfo);
139 static tree build_vtbl_ref_1 (tree, tree);
140 static tree build_vtbl_initializer (tree, tree, tree, tree, int *);
141 static int count_fields (tree);
142 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
143 static void check_bitfield_decl (tree);
144 static void check_field_decl (tree, tree, int *, int *, int *);
145 static void check_field_decls (tree, tree *, int *, int *);
146 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
147 static void build_base_fields (record_layout_info, splay_tree, tree *);
148 static void check_methods (tree);
149 static void remove_zero_width_bit_fields (tree);
150 static void check_bases (tree, int *, int *);
151 static void check_bases_and_members (tree);
152 static tree create_vtable_ptr (tree, tree *);
153 static void include_empty_classes (record_layout_info);
154 static void layout_class_type (tree, tree *);
155 static void fixup_pending_inline (tree);
156 static void fixup_inline_methods (tree);
157 static void propagate_binfo_offsets (tree, tree);
158 static void layout_virtual_bases (record_layout_info, splay_tree);
159 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
160 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
161 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
162 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
163 static void add_vcall_offset (tree, tree, vtbl_init_data *);
164 static void layout_vtable_decl (tree, int);
165 static tree dfs_find_final_overrider_pre (tree, void *);
166 static tree dfs_find_final_overrider_post (tree, void *);
167 static tree find_final_overrider (tree, tree, tree);
168 static int make_new_vtable (tree, tree);
169 static tree get_primary_binfo (tree);
170 static int maybe_indent_hierarchy (FILE *, int, int);
171 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
172 static void dump_class_hierarchy (tree);
173 static void dump_class_hierarchy_1 (FILE *, int, tree);
174 static void dump_array (FILE *, tree);
175 static void dump_vtable (tree, tree, tree);
176 static void dump_vtt (tree, tree);
177 static void dump_thunk (FILE *, int, tree);
178 static tree build_vtable (tree, tree, tree);
179 static void initialize_vtable (tree, tree);
180 static void layout_nonempty_base_or_field (record_layout_info,
181 tree, tree, splay_tree);
182 static tree end_of_class (tree, int);
183 static bool layout_empty_base (tree, tree, splay_tree);
184 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree);
185 static tree dfs_accumulate_vtbl_inits (tree, tree, tree, tree,
187 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
188 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
189 static void clone_constructors_and_destructors (tree);
190 static tree build_clone (tree, tree);
191 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
192 static void build_ctor_vtbl_group (tree, tree);
193 static void build_vtt (tree);
194 static tree binfo_ctor_vtable (tree);
195 static tree *build_vtt_inits (tree, tree, tree *, tree *);
196 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
197 static tree dfs_fixup_binfo_vtbls (tree, void *);
198 static int record_subobject_offset (tree, tree, splay_tree);
199 static int check_subobject_offset (tree, tree, splay_tree);
200 static int walk_subobject_offsets (tree, subobject_offset_fn,
201 tree, splay_tree, tree, int);
202 static void record_subobject_offsets (tree, tree, splay_tree, bool);
203 static int layout_conflict_p (tree, tree, splay_tree, int);
204 static int splay_tree_compare_integer_csts (splay_tree_key k1,
206 static void warn_about_ambiguous_bases (tree);
207 static bool type_requires_array_cookie (tree);
208 static bool contains_empty_class_p (tree);
209 static bool base_derived_from (tree, tree);
210 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
211 static tree end_of_base (tree);
212 static tree get_vcall_index (tree, tree);
214 /* Variables shared between class.c and call.c. */
216 #ifdef GATHER_STATISTICS
218 int n_vtable_entries = 0;
219 int n_vtable_searches = 0;
220 int n_vtable_elems = 0;
221 int n_convert_harshness = 0;
222 int n_compute_conversion_costs = 0;
223 int n_inner_fields_searched = 0;
226 /* Convert to or from a base subobject. EXPR is an expression of type
227 `A' or `A*', an expression of type `B' or `B*' is returned. To
228 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
229 the B base instance within A. To convert base A to derived B, CODE
230 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
231 In this latter case, A must not be a morally virtual base of B.
232 NONNULL is true if EXPR is known to be non-NULL (this is only
233 needed when EXPR is of pointer type). CV qualifiers are preserved
237 build_base_path (enum tree_code code,
242 tree v_binfo = NULL_TREE;
243 tree d_binfo = NULL_TREE;
247 tree null_test = NULL;
248 tree ptr_target_type;
250 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
251 bool has_empty = false;
254 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
255 return error_mark_node;
257 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
260 if (is_empty_class (BINFO_TYPE (probe)))
262 if (!v_binfo && BINFO_VIRTUAL_P (probe))
266 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
268 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
270 gcc_assert ((code == MINUS_EXPR
271 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
272 || (code == PLUS_EXPR
273 && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
275 if (binfo == d_binfo)
279 if (code == MINUS_EXPR && v_binfo)
281 error ("cannot convert from base %qT to derived type %qT via virtual base %qT",
282 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
283 return error_mark_node;
287 /* This must happen before the call to save_expr. */
288 expr = build_unary_op (ADDR_EXPR, expr, 0);
290 offset = BINFO_OFFSET (binfo);
291 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
292 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
294 /* Do we need to look in the vtable for the real offset? */
295 virtual_access = (v_binfo && fixed_type_p <= 0);
297 /* Do we need to check for a null pointer? */
298 if (want_pointer && !nonnull)
300 /* If we know the conversion will not actually change the value
301 of EXPR, then we can avoid testing the expression for NULL.
302 We have to avoid generating a COMPONENT_REF for a base class
303 field, because other parts of the compiler know that such
304 expressions are always non-NULL. */
305 if (!virtual_access && integer_zerop (offset))
308 /* TARGET_TYPE has been extracted from BINFO, and, is
309 therefore always cv-unqualified. Extract the
310 cv-qualifiers from EXPR so that the expression returned
311 matches the input. */
312 class_type = TREE_TYPE (TREE_TYPE (expr));
314 = cp_build_qualified_type (target_type,
315 cp_type_quals (class_type));
316 return build_nop (build_pointer_type (target_type), expr);
318 null_test = error_mark_node;
321 /* Protect against multiple evaluation if necessary. */
322 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
323 expr = save_expr (expr);
325 /* Now that we've saved expr, build the real null test. */
328 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
329 null_test = fold_build2 (NE_EXPR, boolean_type_node,
333 /* If this is a simple base reference, express it as a COMPONENT_REF. */
334 if (code == PLUS_EXPR && !virtual_access
335 /* We don't build base fields for empty bases, and they aren't very
336 interesting to the optimizers anyway. */
339 expr = build_indirect_ref (expr, NULL);
340 expr = build_simple_base_path (expr, binfo);
342 expr = build_address (expr);
343 target_type = TREE_TYPE (expr);
349 /* Going via virtual base V_BINFO. We need the static offset
350 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
351 V_BINFO. That offset is an entry in D_BINFO's vtable. */
354 if (fixed_type_p < 0 && in_base_initializer)
356 /* In a base member initializer, we cannot rely on the
357 vtable being set up. We have to indirect via the
361 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
362 t = build_pointer_type (t);
363 v_offset = convert (t, current_vtt_parm);
364 v_offset = build_indirect_ref (v_offset, NULL);
367 v_offset = build_vfield_ref (build_indirect_ref (expr, NULL),
368 TREE_TYPE (TREE_TYPE (expr)));
370 v_offset = build2 (PLUS_EXPR, TREE_TYPE (v_offset),
371 v_offset, BINFO_VPTR_FIELD (v_binfo));
372 v_offset = build1 (NOP_EXPR,
373 build_pointer_type (ptrdiff_type_node),
375 v_offset = build_indirect_ref (v_offset, NULL);
376 TREE_CONSTANT (v_offset) = 1;
377 TREE_INVARIANT (v_offset) = 1;
379 offset = convert_to_integer (ptrdiff_type_node,
381 BINFO_OFFSET (v_binfo)));
383 if (!integer_zerop (offset))
384 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
386 if (fixed_type_p < 0)
387 /* Negative fixed_type_p means this is a constructor or destructor;
388 virtual base layout is fixed in in-charge [cd]tors, but not in
390 offset = build3 (COND_EXPR, ptrdiff_type_node,
391 build2 (EQ_EXPR, boolean_type_node,
392 current_in_charge_parm, integer_zero_node),
394 convert_to_integer (ptrdiff_type_node,
395 BINFO_OFFSET (binfo)));
400 target_type = cp_build_qualified_type
401 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
402 ptr_target_type = build_pointer_type (target_type);
404 target_type = ptr_target_type;
406 expr = build1 (NOP_EXPR, ptr_target_type, expr);
408 if (!integer_zerop (offset))
409 expr = build2 (code, ptr_target_type, expr, offset);
414 expr = build_indirect_ref (expr, NULL);
418 expr = fold_build3 (COND_EXPR, target_type, null_test, expr,
419 fold_build1 (NOP_EXPR, target_type,
425 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
426 Perform a derived-to-base conversion by recursively building up a
427 sequence of COMPONENT_REFs to the appropriate base fields. */
430 build_simple_base_path (tree expr, tree binfo)
432 tree type = BINFO_TYPE (binfo);
433 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
436 if (d_binfo == NULL_TREE)
440 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
442 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
443 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
444 an lvalue in the front end; only _DECLs and _REFs are lvalues
446 temp = unary_complex_lvalue (ADDR_EXPR, expr);
448 expr = build_indirect_ref (temp, NULL);
454 expr = build_simple_base_path (expr, d_binfo);
456 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
457 field; field = TREE_CHAIN (field))
458 /* Is this the base field created by build_base_field? */
459 if (TREE_CODE (field) == FIELD_DECL
460 && DECL_FIELD_IS_BASE (field)
461 && TREE_TYPE (field) == type)
463 /* We don't use build_class_member_access_expr here, as that
464 has unnecessary checks, and more importantly results in
465 recursive calls to dfs_walk_once. */
466 int type_quals = cp_type_quals (TREE_TYPE (expr));
468 expr = build3 (COMPONENT_REF,
469 cp_build_qualified_type (type, type_quals),
470 expr, field, NULL_TREE);
471 expr = fold_if_not_in_template (expr);
473 /* Mark the expression const or volatile, as appropriate.
474 Even though we've dealt with the type above, we still have
475 to mark the expression itself. */
476 if (type_quals & TYPE_QUAL_CONST)
477 TREE_READONLY (expr) = 1;
478 if (type_quals & TYPE_QUAL_VOLATILE)
479 TREE_THIS_VOLATILE (expr) = 1;
484 /* Didn't find the base field?!? */
488 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
489 type is a class type or a pointer to a class type. In the former
490 case, TYPE is also a class type; in the latter it is another
491 pointer type. If CHECK_ACCESS is true, an error message is emitted
492 if TYPE is inaccessible. If OBJECT has pointer type, the value is
493 assumed to be non-NULL. */
496 convert_to_base (tree object, tree type, bool check_access, bool nonnull)
501 if (TYPE_PTR_P (TREE_TYPE (object)))
503 object_type = TREE_TYPE (TREE_TYPE (object));
504 type = TREE_TYPE (type);
507 object_type = TREE_TYPE (object);
509 binfo = lookup_base (object_type, type,
510 check_access ? ba_check : ba_unique,
512 if (!binfo || binfo == error_mark_node)
513 return error_mark_node;
515 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
518 /* EXPR is an expression with unqualified class type. BASE is a base
519 binfo of that class type. Returns EXPR, converted to the BASE
520 type. This function assumes that EXPR is the most derived class;
521 therefore virtual bases can be found at their static offsets. */
524 convert_to_base_statically (tree expr, tree base)
528 expr_type = TREE_TYPE (expr);
529 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
533 pointer_type = build_pointer_type (expr_type);
535 /* We use fold_build2 and fold_convert below to simplify the trees
536 provided to the optimizers. It is not safe to call these functions
537 when processing a template because they do not handle C++-specific
539 gcc_assert (!processing_template_decl);
540 expr = build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1);
541 if (!integer_zerop (BINFO_OFFSET (base)))
542 expr = fold_build2 (PLUS_EXPR, pointer_type, expr,
543 fold_convert (pointer_type, BINFO_OFFSET (base)));
544 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
545 expr = build_fold_indirect_ref (expr);
553 build_vfield_ref (tree datum, tree type)
555 tree vfield, vcontext;
557 if (datum == error_mark_node)
558 return error_mark_node;
560 /* First, convert to the requested type. */
561 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
562 datum = convert_to_base (datum, type, /*check_access=*/false,
565 /* Second, the requested type may not be the owner of its own vptr.
566 If not, convert to the base class that owns it. We cannot use
567 convert_to_base here, because VCONTEXT may appear more than once
568 in the inheritance hierarchy of TYPE, and thus direct conversion
569 between the types may be ambiguous. Following the path back up
570 one step at a time via primary bases avoids the problem. */
571 vfield = TYPE_VFIELD (type);
572 vcontext = DECL_CONTEXT (vfield);
573 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
575 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
576 type = TREE_TYPE (datum);
579 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
582 /* Given an object INSTANCE, return an expression which yields the
583 vtable element corresponding to INDEX. There are many special
584 cases for INSTANCE which we take care of here, mainly to avoid
585 creating extra tree nodes when we don't have to. */
588 build_vtbl_ref_1 (tree instance, tree idx)
591 tree vtbl = NULL_TREE;
593 /* Try to figure out what a reference refers to, and
594 access its virtual function table directly. */
597 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
599 tree basetype = non_reference (TREE_TYPE (instance));
601 if (fixed_type && !cdtorp)
603 tree binfo = lookup_base (fixed_type, basetype,
604 ba_unique | ba_quiet, NULL);
606 vtbl = unshare_expr (BINFO_VTABLE (binfo));
610 vtbl = build_vfield_ref (instance, basetype);
612 assemble_external (vtbl);
614 aref = build_array_ref (vtbl, idx);
615 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
616 TREE_INVARIANT (aref) = TREE_CONSTANT (aref);
622 build_vtbl_ref (tree instance, tree idx)
624 tree aref = build_vtbl_ref_1 (instance, idx);
629 /* Given a stable object pointer INSTANCE_PTR, return an expression which
630 yields a function pointer corresponding to vtable element INDEX. */
633 build_vfn_ref (tree instance_ptr, tree idx)
637 aref = build_vtbl_ref_1 (build_indirect_ref (instance_ptr, 0), idx);
639 /* When using function descriptors, the address of the
640 vtable entry is treated as a function pointer. */
641 if (TARGET_VTABLE_USES_DESCRIPTORS)
642 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
643 build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1));
645 /* Remember this as a method reference, for later devirtualization. */
646 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
651 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
652 for the given TYPE. */
655 get_vtable_name (tree type)
657 return mangle_vtbl_for_type (type);
660 /* DECL is an entity associated with TYPE, like a virtual table or an
661 implicitly generated constructor. Determine whether or not DECL
662 should have external or internal linkage at the object file
663 level. This routine does not deal with COMDAT linkage and other
664 similar complexities; it simply sets TREE_PUBLIC if it possible for
665 entities in other translation units to contain copies of DECL, in
669 set_linkage_according_to_type (tree type, tree decl)
671 /* If TYPE involves a local class in a function with internal
672 linkage, then DECL should have internal linkage too. Other local
673 classes have no linkage -- but if their containing functions
674 have external linkage, it makes sense for DECL to have external
675 linkage too. That will allow template definitions to be merged,
677 if (no_linkage_check (type, /*relaxed_p=*/true))
679 TREE_PUBLIC (decl) = 0;
680 DECL_INTERFACE_KNOWN (decl) = 1;
683 TREE_PUBLIC (decl) = 1;
686 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
687 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
688 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
691 build_vtable (tree class_type, tree name, tree vtable_type)
695 decl = build_lang_decl (VAR_DECL, name, vtable_type);
696 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
697 now to avoid confusion in mangle_decl. */
698 SET_DECL_ASSEMBLER_NAME (decl, name);
699 DECL_CONTEXT (decl) = class_type;
700 DECL_ARTIFICIAL (decl) = 1;
701 TREE_STATIC (decl) = 1;
702 TREE_READONLY (decl) = 1;
703 DECL_VIRTUAL_P (decl) = 1;
704 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
705 DECL_VTABLE_OR_VTT_P (decl) = 1;
706 /* At one time the vtable info was grabbed 2 words at a time. This
707 fails on sparc unless you have 8-byte alignment. (tiemann) */
708 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
710 set_linkage_according_to_type (class_type, decl);
711 /* The vtable has not been defined -- yet. */
712 DECL_EXTERNAL (decl) = 1;
713 DECL_NOT_REALLY_EXTERN (decl) = 1;
715 /* Mark the VAR_DECL node representing the vtable itself as a
716 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
717 is rather important that such things be ignored because any
718 effort to actually generate DWARF for them will run into
719 trouble when/if we encounter code like:
722 struct S { virtual void member (); };
724 because the artificial declaration of the vtable itself (as
725 manufactured by the g++ front end) will say that the vtable is
726 a static member of `S' but only *after* the debug output for
727 the definition of `S' has already been output. This causes
728 grief because the DWARF entry for the definition of the vtable
729 will try to refer back to an earlier *declaration* of the
730 vtable as a static member of `S' and there won't be one. We
731 might be able to arrange to have the "vtable static member"
732 attached to the member list for `S' before the debug info for
733 `S' get written (which would solve the problem) but that would
734 require more intrusive changes to the g++ front end. */
735 DECL_IGNORED_P (decl) = 1;
740 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
741 or even complete. If this does not exist, create it. If COMPLETE is
742 nonzero, then complete the definition of it -- that will render it
743 impossible to actually build the vtable, but is useful to get at those
744 which are known to exist in the runtime. */
747 get_vtable_decl (tree type, int complete)
751 if (CLASSTYPE_VTABLES (type))
752 return CLASSTYPE_VTABLES (type);
754 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
755 CLASSTYPE_VTABLES (type) = decl;
759 DECL_EXTERNAL (decl) = 1;
760 finish_decl (decl, NULL_TREE, NULL_TREE);
766 /* Build the primary virtual function table for TYPE. If BINFO is
767 non-NULL, build the vtable starting with the initial approximation
768 that it is the same as the one which is the head of the association
769 list. Returns a nonzero value if a new vtable is actually
773 build_primary_vtable (tree binfo, tree type)
778 decl = get_vtable_decl (type, /*complete=*/0);
782 if (BINFO_NEW_VTABLE_MARKED (binfo))
783 /* We have already created a vtable for this base, so there's
784 no need to do it again. */
787 virtuals = copy_list (BINFO_VIRTUALS (binfo));
788 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
789 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
790 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
794 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
795 virtuals = NULL_TREE;
798 #ifdef GATHER_STATISTICS
800 n_vtable_elems += list_length (virtuals);
803 /* Initialize the association list for this type, based
804 on our first approximation. */
805 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
806 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
807 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
811 /* Give BINFO a new virtual function table which is initialized
812 with a skeleton-copy of its original initialization. The only
813 entry that changes is the `delta' entry, so we can really
814 share a lot of structure.
816 FOR_TYPE is the most derived type which caused this table to
819 Returns nonzero if we haven't met BINFO before.
821 The order in which vtables are built (by calling this function) for
822 an object must remain the same, otherwise a binary incompatibility
826 build_secondary_vtable (tree binfo)
828 if (BINFO_NEW_VTABLE_MARKED (binfo))
829 /* We already created a vtable for this base. There's no need to
833 /* Remember that we've created a vtable for this BINFO, so that we
834 don't try to do so again. */
835 SET_BINFO_NEW_VTABLE_MARKED (binfo);
837 /* Make fresh virtual list, so we can smash it later. */
838 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
840 /* Secondary vtables are laid out as part of the same structure as
841 the primary vtable. */
842 BINFO_VTABLE (binfo) = NULL_TREE;
846 /* Create a new vtable for BINFO which is the hierarchy dominated by
847 T. Return nonzero if we actually created a new vtable. */
850 make_new_vtable (tree t, tree binfo)
852 if (binfo == TYPE_BINFO (t))
853 /* In this case, it is *type*'s vtable we are modifying. We start
854 with the approximation that its vtable is that of the
855 immediate base class. */
856 return build_primary_vtable (binfo, t);
858 /* This is our very own copy of `basetype' to play with. Later,
859 we will fill in all the virtual functions that override the
860 virtual functions in these base classes which are not defined
861 by the current type. */
862 return build_secondary_vtable (binfo);
865 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
866 (which is in the hierarchy dominated by T) list FNDECL as its
867 BV_FN. DELTA is the required constant adjustment from the `this'
868 pointer where the vtable entry appears to the `this' required when
869 the function is actually called. */
872 modify_vtable_entry (tree t,
882 if (fndecl != BV_FN (v)
883 || !tree_int_cst_equal (delta, BV_DELTA (v)))
885 /* We need a new vtable for BINFO. */
886 if (make_new_vtable (t, binfo))
888 /* If we really did make a new vtable, we also made a copy
889 of the BINFO_VIRTUALS list. Now, we have to find the
890 corresponding entry in that list. */
891 *virtuals = BINFO_VIRTUALS (binfo);
892 while (BV_FN (*virtuals) != BV_FN (v))
893 *virtuals = TREE_CHAIN (*virtuals);
897 BV_DELTA (v) = delta;
898 BV_VCALL_INDEX (v) = NULL_TREE;
904 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
905 the USING_DECL naming METHOD. Returns true if the method could be
906 added to the method vec. */
909 add_method (tree type, tree method, tree using_decl)
913 bool template_conv_p = false;
915 VEC(tree,gc) *method_vec;
917 bool insert_p = false;
921 if (method == error_mark_node)
924 complete_p = COMPLETE_TYPE_P (type);
925 conv_p = DECL_CONV_FN_P (method);
927 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
928 && DECL_TEMPLATE_CONV_FN_P (method));
930 method_vec = CLASSTYPE_METHOD_VEC (type);
933 /* Make a new method vector. We start with 8 entries. We must
934 allocate at least two (for constructors and destructors), and
935 we're going to end up with an assignment operator at some
937 method_vec = VEC_alloc (tree, gc, 8);
938 /* Create slots for constructors and destructors. */
939 VEC_quick_push (tree, method_vec, NULL_TREE);
940 VEC_quick_push (tree, method_vec, NULL_TREE);
941 CLASSTYPE_METHOD_VEC (type) = method_vec;
944 /* Maintain TYPE_HAS_CONSTRUCTOR, etc. */
945 grok_special_member_properties (method);
947 /* Constructors and destructors go in special slots. */
948 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
949 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
950 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
952 slot = CLASSTYPE_DESTRUCTOR_SLOT;
954 if (TYPE_FOR_JAVA (type))
956 if (!DECL_ARTIFICIAL (method))
957 error ("Java class %qT cannot have a destructor", type);
958 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
959 error ("Java class %qT cannot have an implicit non-trivial "
969 /* See if we already have an entry with this name. */
970 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
971 VEC_iterate (tree, method_vec, slot, m);
977 if (TREE_CODE (m) == TEMPLATE_DECL
978 && DECL_TEMPLATE_CONV_FN_P (m))
982 if (conv_p && !DECL_CONV_FN_P (m))
984 if (DECL_NAME (m) == DECL_NAME (method))
990 && !DECL_CONV_FN_P (m)
991 && DECL_NAME (m) > DECL_NAME (method))
995 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
997 /* Check to see if we've already got this method. */
998 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1000 tree fn = OVL_CURRENT (fns);
1006 if (TREE_CODE (fn) != TREE_CODE (method))
1009 /* [over.load] Member function declarations with the
1010 same name and the same parameter types cannot be
1011 overloaded if any of them is a static member
1012 function declaration.
1014 [namespace.udecl] When a using-declaration brings names
1015 from a base class into a derived class scope, member
1016 functions in the derived class override and/or hide member
1017 functions with the same name and parameter types in a base
1018 class (rather than conflicting). */
1019 fn_type = TREE_TYPE (fn);
1020 method_type = TREE_TYPE (method);
1021 parms1 = TYPE_ARG_TYPES (fn_type);
1022 parms2 = TYPE_ARG_TYPES (method_type);
1024 /* Compare the quals on the 'this' parm. Don't compare
1025 the whole types, as used functions are treated as
1026 coming from the using class in overload resolution. */
1027 if (! DECL_STATIC_FUNCTION_P (fn)
1028 && ! DECL_STATIC_FUNCTION_P (method)
1029 && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
1030 != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
1033 /* For templates, the return type and template parameters
1034 must be identical. */
1035 if (TREE_CODE (fn) == TEMPLATE_DECL
1036 && (!same_type_p (TREE_TYPE (fn_type),
1037 TREE_TYPE (method_type))
1038 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1039 DECL_TEMPLATE_PARMS (method))))
1042 if (! DECL_STATIC_FUNCTION_P (fn))
1043 parms1 = TREE_CHAIN (parms1);
1044 if (! DECL_STATIC_FUNCTION_P (method))
1045 parms2 = TREE_CHAIN (parms2);
1047 if (compparms (parms1, parms2)
1048 && (!DECL_CONV_FN_P (fn)
1049 || same_type_p (TREE_TYPE (fn_type),
1050 TREE_TYPE (method_type))))
1054 if (DECL_CONTEXT (fn) == type)
1055 /* Defer to the local function. */
1057 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1058 error ("repeated using declaration %q+D", using_decl);
1060 error ("using declaration %q+D conflicts with a previous using declaration",
1065 error ("%q+#D cannot be overloaded", method);
1066 error ("with %q+#D", fn);
1069 /* We don't call duplicate_decls here to merge the
1070 declarations because that will confuse things if the
1071 methods have inline definitions. In particular, we
1072 will crash while processing the definitions. */
1077 /* A class should never have more than one destructor. */
1078 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1081 /* Add the new binding. */
1082 overload = build_overload (method, current_fns);
1085 TYPE_HAS_CONVERSION (type) = 1;
1086 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1087 push_class_level_binding (DECL_NAME (method), overload);
1093 /* We only expect to add few methods in the COMPLETE_P case, so
1094 just make room for one more method in that case. */
1096 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1098 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1100 CLASSTYPE_METHOD_VEC (type) = method_vec;
1101 if (slot == VEC_length (tree, method_vec))
1102 VEC_quick_push (tree, method_vec, overload);
1104 VEC_quick_insert (tree, method_vec, slot, overload);
1107 /* Replace the current slot. */
1108 VEC_replace (tree, method_vec, slot, overload);
1112 /* Subroutines of finish_struct. */
1114 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1115 legit, otherwise return 0. */
1118 alter_access (tree t, tree fdecl, tree access)
1122 if (!DECL_LANG_SPECIFIC (fdecl))
1123 retrofit_lang_decl (fdecl);
1125 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1127 elem = purpose_member (t, DECL_ACCESS (fdecl));
1130 if (TREE_VALUE (elem) != access)
1132 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1133 error ("conflicting access specifications for method"
1134 " %q+D, ignored", TREE_TYPE (fdecl));
1136 error ("conflicting access specifications for field %qE, ignored",
1141 /* They're changing the access to the same thing they changed
1142 it to before. That's OK. */
1148 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1149 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1155 /* Process the USING_DECL, which is a member of T. */
1158 handle_using_decl (tree using_decl, tree t)
1160 tree decl = USING_DECL_DECLS (using_decl);
1161 tree name = DECL_NAME (using_decl);
1163 = TREE_PRIVATE (using_decl) ? access_private_node
1164 : TREE_PROTECTED (using_decl) ? access_protected_node
1165 : access_public_node;
1166 tree flist = NULL_TREE;
1169 gcc_assert (!processing_template_decl && decl);
1171 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1174 if (is_overloaded_fn (old_value))
1175 old_value = OVL_CURRENT (old_value);
1177 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1180 old_value = NULL_TREE;
1183 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1185 if (is_overloaded_fn (decl))
1190 else if (is_overloaded_fn (old_value))
1193 /* It's OK to use functions from a base when there are functions with
1194 the same name already present in the current class. */;
1197 error ("%q+D invalid in %q#T", using_decl, t);
1198 error (" because of local method %q+#D with same name",
1199 OVL_CURRENT (old_value));
1203 else if (!DECL_ARTIFICIAL (old_value))
1205 error ("%q+D invalid in %q#T", using_decl, t);
1206 error (" because of local member %q+#D with same name", old_value);
1210 /* Make type T see field decl FDECL with access ACCESS. */
1212 for (; flist; flist = OVL_NEXT (flist))
1214 add_method (t, OVL_CURRENT (flist), using_decl);
1215 alter_access (t, OVL_CURRENT (flist), access);
1218 alter_access (t, decl, access);
1221 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1222 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1223 properties of the bases. */
1226 check_bases (tree t,
1227 int* cant_have_const_ctor_p,
1228 int* no_const_asn_ref_p)
1231 int seen_non_virtual_nearly_empty_base_p;
1235 seen_non_virtual_nearly_empty_base_p = 0;
1237 for (binfo = TYPE_BINFO (t), i = 0;
1238 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1240 tree basetype = TREE_TYPE (base_binfo);
1242 gcc_assert (COMPLETE_TYPE_P (basetype));
1244 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1245 here because the case of virtual functions but non-virtual
1246 dtor is handled in finish_struct_1. */
1247 if (!TYPE_POLYMORPHIC_P (basetype))
1248 warning (OPT_Weffc__,
1249 "base class %q#T has a non-virtual destructor", basetype);
1251 /* If the base class doesn't have copy constructors or
1252 assignment operators that take const references, then the
1253 derived class cannot have such a member automatically
1255 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1256 *cant_have_const_ctor_p = 1;
1257 if (TYPE_HAS_ASSIGN_REF (basetype)
1258 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1259 *no_const_asn_ref_p = 1;
1261 if (BINFO_VIRTUAL_P (base_binfo))
1262 /* A virtual base does not effect nearly emptiness. */
1264 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1266 if (seen_non_virtual_nearly_empty_base_p)
1267 /* And if there is more than one nearly empty base, then the
1268 derived class is not nearly empty either. */
1269 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1271 /* Remember we've seen one. */
1272 seen_non_virtual_nearly_empty_base_p = 1;
1274 else if (!is_empty_class (basetype))
1275 /* If the base class is not empty or nearly empty, then this
1276 class cannot be nearly empty. */
1277 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1279 /* A lot of properties from the bases also apply to the derived
1281 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1282 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1283 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1284 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1285 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1286 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1287 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1288 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1289 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1290 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (basetype);
1294 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1295 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1296 that have had a nearly-empty virtual primary base stolen by some
1297 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1301 determine_primary_bases (tree t)
1304 tree primary = NULL_TREE;
1305 tree type_binfo = TYPE_BINFO (t);
1308 /* Determine the primary bases of our bases. */
1309 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1310 base_binfo = TREE_CHAIN (base_binfo))
1312 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1314 /* See if we're the non-virtual primary of our inheritance
1316 if (!BINFO_VIRTUAL_P (base_binfo))
1318 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1319 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1322 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1323 BINFO_TYPE (parent_primary)))
1324 /* We are the primary binfo. */
1325 BINFO_PRIMARY_P (base_binfo) = 1;
1327 /* Determine if we have a virtual primary base, and mark it so.
1329 if (primary && BINFO_VIRTUAL_P (primary))
1331 tree this_primary = copied_binfo (primary, base_binfo);
1333 if (BINFO_PRIMARY_P (this_primary))
1334 /* Someone already claimed this base. */
1335 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1340 BINFO_PRIMARY_P (this_primary) = 1;
1341 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1343 /* A virtual binfo might have been copied from within
1344 another hierarchy. As we're about to use it as a
1345 primary base, make sure the offsets match. */
1346 delta = size_diffop (convert (ssizetype,
1347 BINFO_OFFSET (base_binfo)),
1349 BINFO_OFFSET (this_primary)));
1351 propagate_binfo_offsets (this_primary, delta);
1356 /* First look for a dynamic direct non-virtual base. */
1357 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1359 tree basetype = BINFO_TYPE (base_binfo);
1361 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1363 primary = base_binfo;
1368 /* A "nearly-empty" virtual base class can be the primary base
1369 class, if no non-virtual polymorphic base can be found. Look for
1370 a nearly-empty virtual dynamic base that is not already a primary
1371 base of something in the hierarchy. If there is no such base,
1372 just pick the first nearly-empty virtual base. */
1374 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1375 base_binfo = TREE_CHAIN (base_binfo))
1376 if (BINFO_VIRTUAL_P (base_binfo)
1377 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1379 if (!BINFO_PRIMARY_P (base_binfo))
1381 /* Found one that is not primary. */
1382 primary = base_binfo;
1386 /* Remember the first candidate. */
1387 primary = base_binfo;
1391 /* If we've got a primary base, use it. */
1394 tree basetype = BINFO_TYPE (primary);
1396 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1397 if (BINFO_PRIMARY_P (primary))
1398 /* We are stealing a primary base. */
1399 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1400 BINFO_PRIMARY_P (primary) = 1;
1401 if (BINFO_VIRTUAL_P (primary))
1405 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1406 /* A virtual binfo might have been copied from within
1407 another hierarchy. As we're about to use it as a primary
1408 base, make sure the offsets match. */
1409 delta = size_diffop (ssize_int (0),
1410 convert (ssizetype, BINFO_OFFSET (primary)));
1412 propagate_binfo_offsets (primary, delta);
1415 primary = TYPE_BINFO (basetype);
1417 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1418 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1419 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1423 /* Set memoizing fields and bits of T (and its variants) for later
1427 finish_struct_bits (tree t)
1431 /* Fix up variants (if any). */
1432 for (variants = TYPE_NEXT_VARIANT (t);
1434 variants = TYPE_NEXT_VARIANT (variants))
1436 /* These fields are in the _TYPE part of the node, not in
1437 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1438 TYPE_HAS_CONSTRUCTOR (variants) = TYPE_HAS_CONSTRUCTOR (t);
1439 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1440 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1441 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1443 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1445 TYPE_BINFO (variants) = TYPE_BINFO (t);
1447 /* Copy whatever these are holding today. */
1448 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1449 TYPE_METHODS (variants) = TYPE_METHODS (t);
1450 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1453 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1454 /* For a class w/o baseclasses, 'finish_struct' has set
1455 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1456 Similarly for a class whose base classes do not have vtables.
1457 When neither of these is true, we might have removed abstract
1458 virtuals (by providing a definition), added some (by declaring
1459 new ones), or redeclared ones from a base class. We need to
1460 recalculate what's really an abstract virtual at this point (by
1461 looking in the vtables). */
1462 get_pure_virtuals (t);
1464 /* If this type has a copy constructor or a destructor, force its
1465 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1466 nonzero. This will cause it to be passed by invisible reference
1467 and prevent it from being returned in a register. */
1468 if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1471 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1472 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1474 TYPE_MODE (variants) = BLKmode;
1475 TREE_ADDRESSABLE (variants) = 1;
1480 /* Issue warnings about T having private constructors, but no friends,
1483 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1484 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1485 non-private static member functions. */
1488 maybe_warn_about_overly_private_class (tree t)
1490 int has_member_fn = 0;
1491 int has_nonprivate_method = 0;
1494 if (!warn_ctor_dtor_privacy
1495 /* If the class has friends, those entities might create and
1496 access instances, so we should not warn. */
1497 || (CLASSTYPE_FRIEND_CLASSES (t)
1498 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1499 /* We will have warned when the template was declared; there's
1500 no need to warn on every instantiation. */
1501 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1502 /* There's no reason to even consider warning about this
1506 /* We only issue one warning, if more than one applies, because
1507 otherwise, on code like:
1510 // Oops - forgot `public:'
1516 we warn several times about essentially the same problem. */
1518 /* Check to see if all (non-constructor, non-destructor) member
1519 functions are private. (Since there are no friends or
1520 non-private statics, we can't ever call any of the private member
1522 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1523 /* We're not interested in compiler-generated methods; they don't
1524 provide any way to call private members. */
1525 if (!DECL_ARTIFICIAL (fn))
1527 if (!TREE_PRIVATE (fn))
1529 if (DECL_STATIC_FUNCTION_P (fn))
1530 /* A non-private static member function is just like a
1531 friend; it can create and invoke private member
1532 functions, and be accessed without a class
1536 has_nonprivate_method = 1;
1537 /* Keep searching for a static member function. */
1539 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1543 if (!has_nonprivate_method && has_member_fn)
1545 /* There are no non-private methods, and there's at least one
1546 private member function that isn't a constructor or
1547 destructor. (If all the private members are
1548 constructors/destructors we want to use the code below that
1549 issues error messages specifically referring to
1550 constructors/destructors.) */
1552 tree binfo = TYPE_BINFO (t);
1554 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1555 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1557 has_nonprivate_method = 1;
1560 if (!has_nonprivate_method)
1562 warning (OPT_Wctor_dtor_privacy,
1563 "all member functions in class %qT are private", t);
1568 /* Even if some of the member functions are non-private, the class
1569 won't be useful for much if all the constructors or destructors
1570 are private: such an object can never be created or destroyed. */
1571 fn = CLASSTYPE_DESTRUCTORS (t);
1572 if (fn && TREE_PRIVATE (fn))
1574 warning (OPT_Wctor_dtor_privacy,
1575 "%q#T only defines a private destructor and has no friends",
1580 if (TYPE_HAS_CONSTRUCTOR (t)
1581 /* Implicitly generated constructors are always public. */
1582 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1583 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1585 int nonprivate_ctor = 0;
1587 /* If a non-template class does not define a copy
1588 constructor, one is defined for it, enabling it to avoid
1589 this warning. For a template class, this does not
1590 happen, and so we would normally get a warning on:
1592 template <class T> class C { private: C(); };
1594 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1595 complete non-template or fully instantiated classes have this
1597 if (!TYPE_HAS_INIT_REF (t))
1598 nonprivate_ctor = 1;
1600 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1602 tree ctor = OVL_CURRENT (fn);
1603 /* Ideally, we wouldn't count copy constructors (or, in
1604 fact, any constructor that takes an argument of the
1605 class type as a parameter) because such things cannot
1606 be used to construct an instance of the class unless
1607 you already have one. But, for now at least, we're
1609 if (! TREE_PRIVATE (ctor))
1611 nonprivate_ctor = 1;
1616 if (nonprivate_ctor == 0)
1618 warning (OPT_Wctor_dtor_privacy,
1619 "%q#T only defines private constructors and has no friends",
1627 gt_pointer_operator new_value;
1631 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1634 method_name_cmp (const void* m1_p, const void* m2_p)
1636 const tree *const m1 = (const tree *) m1_p;
1637 const tree *const m2 = (const tree *) m2_p;
1639 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1641 if (*m1 == NULL_TREE)
1643 if (*m2 == NULL_TREE)
1645 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1650 /* This routine compares two fields like method_name_cmp but using the
1651 pointer operator in resort_field_decl_data. */
1654 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1656 const tree *const m1 = (const tree *) m1_p;
1657 const tree *const m2 = (const tree *) m2_p;
1658 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1660 if (*m1 == NULL_TREE)
1662 if (*m2 == NULL_TREE)
1665 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1666 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1667 resort_data.new_value (&d1, resort_data.cookie);
1668 resort_data.new_value (&d2, resort_data.cookie);
1675 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1678 resort_type_method_vec (void* obj,
1679 void* orig_obj ATTRIBUTE_UNUSED ,
1680 gt_pointer_operator new_value,
1683 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1684 int len = VEC_length (tree, method_vec);
1688 /* The type conversion ops have to live at the front of the vec, so we
1690 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1691 VEC_iterate (tree, method_vec, slot, fn);
1693 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1698 resort_data.new_value = new_value;
1699 resort_data.cookie = cookie;
1700 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1701 resort_method_name_cmp);
1705 /* Warn about duplicate methods in fn_fields.
1707 Sort methods that are not special (i.e., constructors, destructors,
1708 and type conversion operators) so that we can find them faster in
1712 finish_struct_methods (tree t)
1715 VEC(tree,gc) *method_vec;
1718 method_vec = CLASSTYPE_METHOD_VEC (t);
1722 len = VEC_length (tree, method_vec);
1724 /* Clear DECL_IN_AGGR_P for all functions. */
1725 for (fn_fields = TYPE_METHODS (t); fn_fields;
1726 fn_fields = TREE_CHAIN (fn_fields))
1727 DECL_IN_AGGR_P (fn_fields) = 0;
1729 /* Issue warnings about private constructors and such. If there are
1730 no methods, then some public defaults are generated. */
1731 maybe_warn_about_overly_private_class (t);
1733 /* The type conversion ops have to live at the front of the vec, so we
1735 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1736 VEC_iterate (tree, method_vec, slot, fn_fields);
1738 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1741 qsort (VEC_address (tree, method_vec) + slot,
1742 len-slot, sizeof (tree), method_name_cmp);
1745 /* Make BINFO's vtable have N entries, including RTTI entries,
1746 vbase and vcall offsets, etc. Set its type and call the back end
1750 layout_vtable_decl (tree binfo, int n)
1755 atype = build_cplus_array_type (vtable_entry_type,
1756 build_index_type (size_int (n - 1)));
1757 layout_type (atype);
1759 /* We may have to grow the vtable. */
1760 vtable = get_vtbl_decl_for_binfo (binfo);
1761 if (!same_type_p (TREE_TYPE (vtable), atype))
1763 TREE_TYPE (vtable) = atype;
1764 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1765 layout_decl (vtable, 0);
1769 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1770 have the same signature. */
1773 same_signature_p (tree fndecl, tree base_fndecl)
1775 /* One destructor overrides another if they are the same kind of
1777 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1778 && special_function_p (base_fndecl) == special_function_p (fndecl))
1780 /* But a non-destructor never overrides a destructor, nor vice
1781 versa, nor do different kinds of destructors override
1782 one-another. For example, a complete object destructor does not
1783 override a deleting destructor. */
1784 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1787 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1788 || (DECL_CONV_FN_P (fndecl)
1789 && DECL_CONV_FN_P (base_fndecl)
1790 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1791 DECL_CONV_FN_TYPE (base_fndecl))))
1793 tree types, base_types;
1794 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1795 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1796 if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1797 == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1798 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1804 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1808 base_derived_from (tree derived, tree base)
1812 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1814 if (probe == derived)
1816 else if (BINFO_VIRTUAL_P (probe))
1817 /* If we meet a virtual base, we can't follow the inheritance
1818 any more. See if the complete type of DERIVED contains
1819 such a virtual base. */
1820 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1826 typedef struct find_final_overrider_data_s {
1827 /* The function for which we are trying to find a final overrider. */
1829 /* The base class in which the function was declared. */
1830 tree declaring_base;
1831 /* The candidate overriders. */
1833 /* Path to most derived. */
1834 VEC(tree,heap) *path;
1835 } find_final_overrider_data;
1837 /* Add the overrider along the current path to FFOD->CANDIDATES.
1838 Returns true if an overrider was found; false otherwise. */
1841 dfs_find_final_overrider_1 (tree binfo,
1842 find_final_overrider_data *ffod,
1847 /* If BINFO is not the most derived type, try a more derived class.
1848 A definition there will overrider a definition here. */
1852 if (dfs_find_final_overrider_1
1853 (VEC_index (tree, ffod->path, depth), ffod, depth))
1857 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1860 tree *candidate = &ffod->candidates;
1862 /* Remove any candidates overridden by this new function. */
1865 /* If *CANDIDATE overrides METHOD, then METHOD
1866 cannot override anything else on the list. */
1867 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1869 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1870 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1871 *candidate = TREE_CHAIN (*candidate);
1873 candidate = &TREE_CHAIN (*candidate);
1876 /* Add the new function. */
1877 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1884 /* Called from find_final_overrider via dfs_walk. */
1887 dfs_find_final_overrider_pre (tree binfo, void *data)
1889 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1891 if (binfo == ffod->declaring_base)
1892 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1893 VEC_safe_push (tree, heap, ffod->path, binfo);
1899 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1901 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1902 VEC_pop (tree, ffod->path);
1907 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1908 FN and whose TREE_VALUE is the binfo for the base where the
1909 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1910 DERIVED) is the base object in which FN is declared. */
1913 find_final_overrider (tree derived, tree binfo, tree fn)
1915 find_final_overrider_data ffod;
1917 /* Getting this right is a little tricky. This is valid:
1919 struct S { virtual void f (); };
1920 struct T { virtual void f (); };
1921 struct U : public S, public T { };
1923 even though calling `f' in `U' is ambiguous. But,
1925 struct R { virtual void f(); };
1926 struct S : virtual public R { virtual void f (); };
1927 struct T : virtual public R { virtual void f (); };
1928 struct U : public S, public T { };
1930 is not -- there's no way to decide whether to put `S::f' or
1931 `T::f' in the vtable for `R'.
1933 The solution is to look at all paths to BINFO. If we find
1934 different overriders along any two, then there is a problem. */
1935 if (DECL_THUNK_P (fn))
1936 fn = THUNK_TARGET (fn);
1938 /* Determine the depth of the hierarchy. */
1940 ffod.declaring_base = binfo;
1941 ffod.candidates = NULL_TREE;
1942 ffod.path = VEC_alloc (tree, heap, 30);
1944 dfs_walk_all (derived, dfs_find_final_overrider_pre,
1945 dfs_find_final_overrider_post, &ffod);
1947 VEC_free (tree, heap, ffod.path);
1949 /* If there was no winner, issue an error message. */
1950 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
1951 return error_mark_node;
1953 return ffod.candidates;
1956 /* Return the index of the vcall offset for FN when TYPE is used as a
1960 get_vcall_index (tree fn, tree type)
1962 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
1966 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
1967 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
1968 || same_signature_p (fn, p->purpose))
1971 /* There should always be an appropriate index. */
1975 /* Update an entry in the vtable for BINFO, which is in the hierarchy
1976 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
1977 corresponding position in the BINFO_VIRTUALS list. */
1980 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
1988 tree overrider_fn, overrider_target;
1989 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
1990 tree over_return, base_return;
1993 /* Find the nearest primary base (possibly binfo itself) which defines
1994 this function; this is the class the caller will convert to when
1995 calling FN through BINFO. */
1996 for (b = binfo; ; b = get_primary_binfo (b))
1999 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2002 /* The nearest definition is from a lost primary. */
2003 if (BINFO_LOST_PRIMARY_P (b))
2008 /* Find the final overrider. */
2009 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2010 if (overrider == error_mark_node)
2012 error ("no unique final overrider for %qD in %qT", target_fn, t);
2015 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2017 /* Check for adjusting covariant return types. */
2018 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2019 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2021 if (POINTER_TYPE_P (over_return)
2022 && TREE_CODE (over_return) == TREE_CODE (base_return)
2023 && CLASS_TYPE_P (TREE_TYPE (over_return))
2024 && CLASS_TYPE_P (TREE_TYPE (base_return))
2025 /* If the overrider is invalid, don't even try. */
2026 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2028 /* If FN is a covariant thunk, we must figure out the adjustment
2029 to the final base FN was converting to. As OVERRIDER_TARGET might
2030 also be converting to the return type of FN, we have to
2031 combine the two conversions here. */
2032 tree fixed_offset, virtual_offset;
2034 over_return = TREE_TYPE (over_return);
2035 base_return = TREE_TYPE (base_return);
2037 if (DECL_THUNK_P (fn))
2039 gcc_assert (DECL_RESULT_THUNK_P (fn));
2040 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2041 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2044 fixed_offset = virtual_offset = NULL_TREE;
2047 /* Find the equivalent binfo within the return type of the
2048 overriding function. We will want the vbase offset from
2050 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2052 else if (!same_type_ignoring_top_level_qualifiers_p
2053 (over_return, base_return))
2055 /* There was no existing virtual thunk (which takes
2056 precedence). So find the binfo of the base function's
2057 return type within the overriding function's return type.
2058 We cannot call lookup base here, because we're inside a
2059 dfs_walk, and will therefore clobber the BINFO_MARKED
2060 flags. Fortunately we know the covariancy is valid (it
2061 has already been checked), so we can just iterate along
2062 the binfos, which have been chained in inheritance graph
2063 order. Of course it is lame that we have to repeat the
2064 search here anyway -- we should really be caching pieces
2065 of the vtable and avoiding this repeated work. */
2066 tree thunk_binfo, base_binfo;
2068 /* Find the base binfo within the overriding function's
2069 return type. We will always find a thunk_binfo, except
2070 when the covariancy is invalid (which we will have
2071 already diagnosed). */
2072 for (base_binfo = TYPE_BINFO (base_return),
2073 thunk_binfo = TYPE_BINFO (over_return);
2075 thunk_binfo = TREE_CHAIN (thunk_binfo))
2076 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2077 BINFO_TYPE (base_binfo)))
2080 /* See if virtual inheritance is involved. */
2081 for (virtual_offset = thunk_binfo;
2083 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2084 if (BINFO_VIRTUAL_P (virtual_offset))
2088 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2090 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2094 /* We convert via virtual base. Adjust the fixed
2095 offset to be from there. */
2096 offset = size_diffop
2098 (ssizetype, BINFO_OFFSET (virtual_offset)));
2101 /* There was an existing fixed offset, this must be
2102 from the base just converted to, and the base the
2103 FN was thunking to. */
2104 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2106 fixed_offset = offset;
2110 if (fixed_offset || virtual_offset)
2111 /* Replace the overriding function with a covariant thunk. We
2112 will emit the overriding function in its own slot as
2114 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2115 fixed_offset, virtual_offset);
2118 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2119 !DECL_THUNK_P (fn));
2121 /* Assume that we will produce a thunk that convert all the way to
2122 the final overrider, and not to an intermediate virtual base. */
2123 virtual_base = NULL_TREE;
2125 /* See if we can convert to an intermediate virtual base first, and then
2126 use the vcall offset located there to finish the conversion. */
2127 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2129 /* If we find the final overrider, then we can stop
2131 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2132 BINFO_TYPE (TREE_VALUE (overrider))))
2135 /* If we find a virtual base, and we haven't yet found the
2136 overrider, then there is a virtual base between the
2137 declaring base (first_defn) and the final overrider. */
2138 if (BINFO_VIRTUAL_P (b))
2145 if (overrider_fn != overrider_target && !virtual_base)
2147 /* The ABI specifies that a covariant thunk includes a mangling
2148 for a this pointer adjustment. This-adjusting thunks that
2149 override a function from a virtual base have a vcall
2150 adjustment. When the virtual base in question is a primary
2151 virtual base, we know the adjustments are zero, (and in the
2152 non-covariant case, we would not use the thunk).
2153 Unfortunately we didn't notice this could happen, when
2154 designing the ABI and so never mandated that such a covariant
2155 thunk should be emitted. Because we must use the ABI mandated
2156 name, we must continue searching from the binfo where we
2157 found the most recent definition of the function, towards the
2158 primary binfo which first introduced the function into the
2159 vtable. If that enters a virtual base, we must use a vcall
2160 this-adjusting thunk. Bleah! */
2161 tree probe = first_defn;
2163 while ((probe = get_primary_binfo (probe))
2164 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2165 if (BINFO_VIRTUAL_P (probe))
2166 virtual_base = probe;
2169 /* Even if we find a virtual base, the correct delta is
2170 between the overrider and the binfo we're building a vtable
2172 goto virtual_covariant;
2175 /* Compute the constant adjustment to the `this' pointer. The
2176 `this' pointer, when this function is called, will point at BINFO
2177 (or one of its primary bases, which are at the same offset). */
2179 /* The `this' pointer needs to be adjusted from the declaration to
2180 the nearest virtual base. */
2181 delta = size_diffop (convert (ssizetype, BINFO_OFFSET (virtual_base)),
2182 convert (ssizetype, BINFO_OFFSET (first_defn)));
2184 /* If the nearest definition is in a lost primary, we don't need an
2185 entry in our vtable. Except possibly in a constructor vtable,
2186 if we happen to get our primary back. In that case, the offset
2187 will be zero, as it will be a primary base. */
2188 delta = size_zero_node;
2190 /* The `this' pointer needs to be adjusted from pointing to
2191 BINFO to pointing at the base where the final overrider
2194 delta = size_diffop (convert (ssizetype,
2195 BINFO_OFFSET (TREE_VALUE (overrider))),
2196 convert (ssizetype, BINFO_OFFSET (binfo)));
2198 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2201 BV_VCALL_INDEX (*virtuals)
2202 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2204 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2207 /* Called from modify_all_vtables via dfs_walk. */
2210 dfs_modify_vtables (tree binfo, void* data)
2212 tree t = (tree) data;
2217 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2218 /* A base without a vtable needs no modification, and its bases
2219 are uninteresting. */
2220 return dfs_skip_bases;
2222 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2223 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2224 /* Don't do the primary vtable, if it's new. */
2227 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2228 /* There's no need to modify the vtable for a non-virtual primary
2229 base; we're not going to use that vtable anyhow. We do still
2230 need to do this for virtual primary bases, as they could become
2231 non-primary in a construction vtable. */
2234 make_new_vtable (t, binfo);
2236 /* Now, go through each of the virtual functions in the virtual
2237 function table for BINFO. Find the final overrider, and update
2238 the BINFO_VIRTUALS list appropriately. */
2239 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2240 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2242 ix++, virtuals = TREE_CHAIN (virtuals),
2243 old_virtuals = TREE_CHAIN (old_virtuals))
2244 update_vtable_entry_for_fn (t,
2246 BV_FN (old_virtuals),
2252 /* Update all of the primary and secondary vtables for T. Create new
2253 vtables as required, and initialize their RTTI information. Each
2254 of the functions in VIRTUALS is declared in T and may override a
2255 virtual function from a base class; find and modify the appropriate
2256 entries to point to the overriding functions. Returns a list, in
2257 declaration order, of the virtual functions that are declared in T,
2258 but do not appear in the primary base class vtable, and which
2259 should therefore be appended to the end of the vtable for T. */
2262 modify_all_vtables (tree t, tree virtuals)
2264 tree binfo = TYPE_BINFO (t);
2267 /* Update all of the vtables. */
2268 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2270 /* Add virtual functions not already in our primary vtable. These
2271 will be both those introduced by this class, and those overridden
2272 from secondary bases. It does not include virtuals merely
2273 inherited from secondary bases. */
2274 for (fnsp = &virtuals; *fnsp; )
2276 tree fn = TREE_VALUE (*fnsp);
2278 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2279 || DECL_VINDEX (fn) == error_mark_node)
2281 /* We don't need to adjust the `this' pointer when
2282 calling this function. */
2283 BV_DELTA (*fnsp) = integer_zero_node;
2284 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2286 /* This is a function not already in our vtable. Keep it. */
2287 fnsp = &TREE_CHAIN (*fnsp);
2290 /* We've already got an entry for this function. Skip it. */
2291 *fnsp = TREE_CHAIN (*fnsp);
2297 /* Get the base virtual function declarations in T that have the
2301 get_basefndecls (tree name, tree t)
2304 tree base_fndecls = NULL_TREE;
2305 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2308 /* Find virtual functions in T with the indicated NAME. */
2309 i = lookup_fnfields_1 (t, name);
2311 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2313 methods = OVL_NEXT (methods))
2315 tree method = OVL_CURRENT (methods);
2317 if (TREE_CODE (method) == FUNCTION_DECL
2318 && DECL_VINDEX (method))
2319 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2323 return base_fndecls;
2325 for (i = 0; i < n_baseclasses; i++)
2327 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2328 base_fndecls = chainon (get_basefndecls (name, basetype),
2332 return base_fndecls;
2335 /* If this declaration supersedes the declaration of
2336 a method declared virtual in the base class, then
2337 mark this field as being virtual as well. */
2340 check_for_override (tree decl, tree ctype)
2342 if (TREE_CODE (decl) == TEMPLATE_DECL)
2343 /* In [temp.mem] we have:
2345 A specialization of a member function template does not
2346 override a virtual function from a base class. */
2348 if ((DECL_DESTRUCTOR_P (decl)
2349 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2350 || DECL_CONV_FN_P (decl))
2351 && look_for_overrides (ctype, decl)
2352 && !DECL_STATIC_FUNCTION_P (decl))
2353 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2354 the error_mark_node so that we know it is an overriding
2356 DECL_VINDEX (decl) = decl;
2358 if (DECL_VIRTUAL_P (decl))
2360 if (!DECL_VINDEX (decl))
2361 DECL_VINDEX (decl) = error_mark_node;
2362 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2366 /* Warn about hidden virtual functions that are not overridden in t.
2367 We know that constructors and destructors don't apply. */
2370 warn_hidden (tree t)
2372 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2376 /* We go through each separately named virtual function. */
2377 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2378 VEC_iterate (tree, method_vec, i, fns);
2389 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2390 have the same name. Figure out what name that is. */
2391 name = DECL_NAME (OVL_CURRENT (fns));
2392 /* There are no possibly hidden functions yet. */
2393 base_fndecls = NULL_TREE;
2394 /* Iterate through all of the base classes looking for possibly
2395 hidden functions. */
2396 for (binfo = TYPE_BINFO (t), j = 0;
2397 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2399 tree basetype = BINFO_TYPE (base_binfo);
2400 base_fndecls = chainon (get_basefndecls (name, basetype),
2404 /* If there are no functions to hide, continue. */
2408 /* Remove any overridden functions. */
2409 for (fn = fns; fn; fn = OVL_NEXT (fn))
2411 fndecl = OVL_CURRENT (fn);
2412 if (DECL_VINDEX (fndecl))
2414 tree *prev = &base_fndecls;
2417 /* If the method from the base class has the same
2418 signature as the method from the derived class, it
2419 has been overridden. */
2420 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2421 *prev = TREE_CHAIN (*prev);
2423 prev = &TREE_CHAIN (*prev);
2427 /* Now give a warning for all base functions without overriders,
2428 as they are hidden. */
2429 while (base_fndecls)
2431 /* Here we know it is a hider, and no overrider exists. */
2432 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2433 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2434 base_fndecls = TREE_CHAIN (base_fndecls);
2439 /* Check for things that are invalid. There are probably plenty of other
2440 things we should check for also. */
2443 finish_struct_anon (tree t)
2447 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2449 if (TREE_STATIC (field))
2451 if (TREE_CODE (field) != FIELD_DECL)
2454 if (DECL_NAME (field) == NULL_TREE
2455 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2457 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2458 for (; elt; elt = TREE_CHAIN (elt))
2460 /* We're generally only interested in entities the user
2461 declared, but we also find nested classes by noticing
2462 the TYPE_DECL that we create implicitly. You're
2463 allowed to put one anonymous union inside another,
2464 though, so we explicitly tolerate that. We use
2465 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2466 we also allow unnamed types used for defining fields. */
2467 if (DECL_ARTIFICIAL (elt)
2468 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2469 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2472 if (TREE_CODE (elt) != FIELD_DECL)
2474 pedwarn ("%q+#D invalid; an anonymous union can "
2475 "only have non-static data members", elt);
2479 if (TREE_PRIVATE (elt))
2480 pedwarn ("private member %q+#D in anonymous union", elt);
2481 else if (TREE_PROTECTED (elt))
2482 pedwarn ("protected member %q+#D in anonymous union", elt);
2484 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2485 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2491 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2492 will be used later during class template instantiation.
2493 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2494 a non-static member data (FIELD_DECL), a member function
2495 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2496 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2497 When FRIEND_P is nonzero, T is either a friend class
2498 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2499 (FUNCTION_DECL, TEMPLATE_DECL). */
2502 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2504 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2505 if (CLASSTYPE_TEMPLATE_INFO (type))
2506 CLASSTYPE_DECL_LIST (type)
2507 = tree_cons (friend_p ? NULL_TREE : type,
2508 t, CLASSTYPE_DECL_LIST (type));
2511 /* Create default constructors, assignment operators, and so forth for
2512 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2513 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2514 the class cannot have a default constructor, copy constructor
2515 taking a const reference argument, or an assignment operator taking
2516 a const reference, respectively. */
2519 add_implicitly_declared_members (tree t,
2520 int cant_have_const_cctor,
2521 int cant_have_const_assignment)
2524 if (!CLASSTYPE_DESTRUCTORS (t))
2526 /* In general, we create destructors lazily. */
2527 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2528 /* However, if the implicit destructor is non-trivial
2529 destructor, we sometimes have to create it at this point. */
2530 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2534 if (TYPE_FOR_JAVA (t))
2535 /* If this a Java class, any non-trivial destructor is
2536 invalid, even if compiler-generated. Therefore, if the
2537 destructor is non-trivial we create it now. */
2545 /* If the implicit destructor will be virtual, then we must
2546 generate it now because (unfortunately) we do not
2547 generate virtual tables lazily. */
2548 binfo = TYPE_BINFO (t);
2549 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2554 base_type = BINFO_TYPE (base_binfo);
2555 dtor = CLASSTYPE_DESTRUCTORS (base_type);
2556 if (dtor && DECL_VIRTUAL_P (dtor))
2564 /* If we can't get away with being lazy, generate the destructor
2567 lazily_declare_fn (sfk_destructor, t);
2571 /* Default constructor. */
2572 if (! TYPE_HAS_CONSTRUCTOR (t))
2574 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2575 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2578 /* Copy constructor. */
2579 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2581 TYPE_HAS_INIT_REF (t) = 1;
2582 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2583 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2584 TYPE_HAS_CONSTRUCTOR (t) = 1;
2587 /* If there is no assignment operator, one will be created if and
2588 when it is needed. For now, just record whether or not the type
2589 of the parameter to the assignment operator will be a const or
2590 non-const reference. */
2591 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2593 TYPE_HAS_ASSIGN_REF (t) = 1;
2594 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2595 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2599 /* Subroutine of finish_struct_1. Recursively count the number of fields
2600 in TYPE, including anonymous union members. */
2603 count_fields (tree fields)
2607 for (x = fields; x; x = TREE_CHAIN (x))
2609 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2610 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2617 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2618 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2621 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2624 for (x = fields; x; x = TREE_CHAIN (x))
2626 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2627 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2629 field_vec->elts[idx++] = x;
2634 /* FIELD is a bit-field. We are finishing the processing for its
2635 enclosing type. Issue any appropriate messages and set appropriate
2639 check_bitfield_decl (tree field)
2641 tree type = TREE_TYPE (field);
2644 /* Extract the declared width of the bitfield, which has been
2645 temporarily stashed in DECL_INITIAL. */
2646 w = DECL_INITIAL (field);
2647 gcc_assert (w != NULL_TREE);
2648 /* Remove the bit-field width indicator so that the rest of the
2649 compiler does not treat that value as an initializer. */
2650 DECL_INITIAL (field) = NULL_TREE;
2652 /* Detect invalid bit-field type. */
2653 if (!INTEGRAL_TYPE_P (type))
2655 error ("bit-field %q+#D with non-integral type", field);
2656 TREE_TYPE (field) = error_mark_node;
2657 w = error_mark_node;
2661 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2664 /* detect invalid field size. */
2665 w = integral_constant_value (w);
2667 if (TREE_CODE (w) != INTEGER_CST)
2669 error ("bit-field %q+D width not an integer constant", field);
2670 w = error_mark_node;
2672 else if (tree_int_cst_sgn (w) < 0)
2674 error ("negative width in bit-field %q+D", field);
2675 w = error_mark_node;
2677 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2679 error ("zero width for bit-field %q+D", field);
2680 w = error_mark_node;
2682 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2683 && TREE_CODE (type) != ENUMERAL_TYPE
2684 && TREE_CODE (type) != BOOLEAN_TYPE)
2685 warning (0, "width of %q+D exceeds its type", field);
2686 else if (TREE_CODE (type) == ENUMERAL_TYPE
2687 && (0 > compare_tree_int (w,
2688 min_precision (TYPE_MIN_VALUE (type),
2689 TYPE_UNSIGNED (type)))
2690 || 0 > compare_tree_int (w,
2692 (TYPE_MAX_VALUE (type),
2693 TYPE_UNSIGNED (type)))))
2694 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2697 if (w != error_mark_node)
2699 DECL_SIZE (field) = convert (bitsizetype, w);
2700 DECL_BIT_FIELD (field) = 1;
2704 /* Non-bit-fields are aligned for their type. */
2705 DECL_BIT_FIELD (field) = 0;
2706 CLEAR_DECL_C_BIT_FIELD (field);
2710 /* FIELD is a non bit-field. We are finishing the processing for its
2711 enclosing type T. Issue any appropriate messages and set appropriate
2715 check_field_decl (tree field,
2717 int* cant_have_const_ctor,
2718 int* no_const_asn_ref,
2719 int* any_default_members)
2721 tree type = strip_array_types (TREE_TYPE (field));
2723 /* An anonymous union cannot contain any fields which would change
2724 the settings of CANT_HAVE_CONST_CTOR and friends. */
2725 if (ANON_UNION_TYPE_P (type))
2727 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2728 structs. So, we recurse through their fields here. */
2729 else if (ANON_AGGR_TYPE_P (type))
2733 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2734 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2735 check_field_decl (fields, t, cant_have_const_ctor,
2736 no_const_asn_ref, any_default_members);
2738 /* Check members with class type for constructors, destructors,
2740 else if (CLASS_TYPE_P (type))
2742 /* Never let anything with uninheritable virtuals
2743 make it through without complaint. */
2744 abstract_virtuals_error (field, type);
2746 if (TREE_CODE (t) == UNION_TYPE)
2748 if (TYPE_NEEDS_CONSTRUCTING (type))
2749 error ("member %q+#D with constructor not allowed in union",
2751 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2752 error ("member %q+#D with destructor not allowed in union", field);
2753 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2754 error ("member %q+#D with copy assignment operator not allowed in union",
2759 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2760 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2761 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2762 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2763 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2764 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (type);
2767 if (!TYPE_HAS_CONST_INIT_REF (type))
2768 *cant_have_const_ctor = 1;
2770 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2771 *no_const_asn_ref = 1;
2773 if (DECL_INITIAL (field) != NULL_TREE)
2775 /* `build_class_init_list' does not recognize
2777 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2778 error ("multiple fields in union %qT initialized", t);
2779 *any_default_members = 1;
2783 /* Check the data members (both static and non-static), class-scoped
2784 typedefs, etc., appearing in the declaration of T. Issue
2785 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2786 declaration order) of access declarations; each TREE_VALUE in this
2787 list is a USING_DECL.
2789 In addition, set the following flags:
2792 The class is empty, i.e., contains no non-static data members.
2794 CANT_HAVE_CONST_CTOR_P
2795 This class cannot have an implicitly generated copy constructor
2796 taking a const reference.
2798 CANT_HAVE_CONST_ASN_REF
2799 This class cannot have an implicitly generated assignment
2800 operator taking a const reference.
2802 All of these flags should be initialized before calling this
2805 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2806 fields can be added by adding to this chain. */
2809 check_field_decls (tree t, tree *access_decls,
2810 int *cant_have_const_ctor_p,
2811 int *no_const_asn_ref_p)
2816 int any_default_members;
2819 /* Assume there are no access declarations. */
2820 *access_decls = NULL_TREE;
2821 /* Assume this class has no pointer members. */
2822 has_pointers = false;
2823 /* Assume none of the members of this class have default
2825 any_default_members = 0;
2827 for (field = &TYPE_FIELDS (t); *field; field = next)
2830 tree type = TREE_TYPE (x);
2832 next = &TREE_CHAIN (x);
2834 if (TREE_CODE (x) == USING_DECL)
2836 /* Prune the access declaration from the list of fields. */
2837 *field = TREE_CHAIN (x);
2839 /* Save the access declarations for our caller. */
2840 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2842 /* Since we've reset *FIELD there's no reason to skip to the
2848 if (TREE_CODE (x) == TYPE_DECL
2849 || TREE_CODE (x) == TEMPLATE_DECL)
2852 /* If we've gotten this far, it's a data member, possibly static,
2853 or an enumerator. */
2854 DECL_CONTEXT (x) = t;
2856 /* When this goes into scope, it will be a non-local reference. */
2857 DECL_NONLOCAL (x) = 1;
2859 if (TREE_CODE (t) == UNION_TYPE)
2863 If a union contains a static data member, or a member of
2864 reference type, the program is ill-formed. */
2865 if (TREE_CODE (x) == VAR_DECL)
2867 error ("%q+D may not be static because it is a member of a union", x);
2870 if (TREE_CODE (type) == REFERENCE_TYPE)
2872 error ("%q+D may not have reference type %qT because"
2873 " it is a member of a union",
2879 /* Perform error checking that did not get done in
2881 if (TREE_CODE (type) == FUNCTION_TYPE)
2883 error ("field %q+D invalidly declared function type", x);
2884 type = build_pointer_type (type);
2885 TREE_TYPE (x) = type;
2887 else if (TREE_CODE (type) == METHOD_TYPE)
2889 error ("field %q+D invalidly declared method type", x);
2890 type = build_pointer_type (type);
2891 TREE_TYPE (x) = type;
2894 if (type == error_mark_node)
2897 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
2900 /* Now it can only be a FIELD_DECL. */
2902 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
2903 CLASSTYPE_NON_AGGREGATE (t) = 1;
2905 /* If this is of reference type, check if it needs an init.
2906 Also do a little ANSI jig if necessary. */
2907 if (TREE_CODE (type) == REFERENCE_TYPE)
2909 CLASSTYPE_NON_POD_P (t) = 1;
2910 if (DECL_INITIAL (x) == NULL_TREE)
2911 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2913 /* ARM $12.6.2: [A member initializer list] (or, for an
2914 aggregate, initialization by a brace-enclosed list) is the
2915 only way to initialize nonstatic const and reference
2917 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2919 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
2921 warning (OPT_Wextra, "non-static reference %q+#D in class without a constructor", x);
2924 type = strip_array_types (type);
2926 if (TYPE_PACKED (t))
2928 if (!pod_type_p (type) && !TYPE_PACKED (type))
2932 "ignoring packed attribute because of unpacked non-POD field %q+#D",
2936 else if (TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
2937 DECL_PACKED (x) = 1;
2940 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
2941 /* We don't treat zero-width bitfields as making a class
2946 /* The class is non-empty. */
2947 CLASSTYPE_EMPTY_P (t) = 0;
2948 /* The class is not even nearly empty. */
2949 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
2950 /* If one of the data members contains an empty class,
2952 if (CLASS_TYPE_P (type)
2953 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
2954 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
2957 /* This is used by -Weffc++ (see below). Warn only for pointers
2958 to members which might hold dynamic memory. So do not warn
2959 for pointers to functions or pointers to members. */
2960 if (TYPE_PTR_P (type)
2961 && !TYPE_PTRFN_P (type)
2962 && !TYPE_PTR_TO_MEMBER_P (type))
2963 has_pointers = true;
2965 if (CLASS_TYPE_P (type))
2967 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
2968 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2969 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
2970 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
2973 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
2974 CLASSTYPE_HAS_MUTABLE (t) = 1;
2976 if (! pod_type_p (type))
2977 /* DR 148 now allows pointers to members (which are POD themselves),
2978 to be allowed in POD structs. */
2979 CLASSTYPE_NON_POD_P (t) = 1;
2981 if (! zero_init_p (type))
2982 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
2984 /* If any field is const, the structure type is pseudo-const. */
2985 if (CP_TYPE_CONST_P (type))
2987 C_TYPE_FIELDS_READONLY (t) = 1;
2988 if (DECL_INITIAL (x) == NULL_TREE)
2989 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
2991 /* ARM $12.6.2: [A member initializer list] (or, for an
2992 aggregate, initialization by a brace-enclosed list) is the
2993 only way to initialize nonstatic const and reference
2995 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2997 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
2999 warning (OPT_Wextra, "non-static const member %q+#D in class without a constructor", x);
3001 /* A field that is pseudo-const makes the structure likewise. */
3002 else if (CLASS_TYPE_P (type))
3004 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3005 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3006 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3007 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3010 /* Core issue 80: A nonstatic data member is required to have a
3011 different name from the class iff the class has a
3012 user-defined constructor. */
3013 if (constructor_name_p (DECL_NAME (x), t) && TYPE_HAS_CONSTRUCTOR (t))
3014 pedwarn ("field %q+#D with same name as class", x);
3016 /* We set DECL_C_BIT_FIELD in grokbitfield.
3017 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3018 if (DECL_C_BIT_FIELD (x))
3019 check_bitfield_decl (x);
3021 check_field_decl (x, t,
3022 cant_have_const_ctor_p,
3024 &any_default_members);
3027 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3028 it should also define a copy constructor and an assignment operator to
3029 implement the correct copy semantic (deep vs shallow, etc.). As it is
3030 not feasible to check whether the constructors do allocate dynamic memory
3031 and store it within members, we approximate the warning like this:
3033 -- Warn only if there are members which are pointers
3034 -- Warn only if there is a non-trivial constructor (otherwise,
3035 there cannot be memory allocated).
3036 -- Warn only if there is a non-trivial destructor. We assume that the
3037 user at least implemented the cleanup correctly, and a destructor
3038 is needed to free dynamic memory.
3040 This seems enough for practical purposes. */
3043 && TYPE_HAS_CONSTRUCTOR (t)
3044 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3045 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3047 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3049 if (! TYPE_HAS_INIT_REF (t))
3051 warning (OPT_Weffc__,
3052 " but does not override %<%T(const %T&)%>", t, t);
3053 if (!TYPE_HAS_ASSIGN_REF (t))
3054 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3056 else if (! TYPE_HAS_ASSIGN_REF (t))
3057 warning (OPT_Weffc__,
3058 " but does not override %<operator=(const %T&)%>", t);
3061 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3063 TYPE_PACKED (t) = 0;
3065 /* Check anonymous struct/anonymous union fields. */
3066 finish_struct_anon (t);
3068 /* We've built up the list of access declarations in reverse order.
3070 *access_decls = nreverse (*access_decls);
3073 /* If TYPE is an empty class type, records its OFFSET in the table of
3077 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3081 if (!is_empty_class (type))
3084 /* Record the location of this empty object in OFFSETS. */
3085 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3087 n = splay_tree_insert (offsets,
3088 (splay_tree_key) offset,
3089 (splay_tree_value) NULL_TREE);
3090 n->value = ((splay_tree_value)
3091 tree_cons (NULL_TREE,
3098 /* Returns nonzero if TYPE is an empty class type and there is
3099 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3102 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3107 if (!is_empty_class (type))
3110 /* Record the location of this empty object in OFFSETS. */
3111 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3115 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3116 if (same_type_p (TREE_VALUE (t), type))
3122 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3123 F for every subobject, passing it the type, offset, and table of
3124 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3127 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3128 than MAX_OFFSET will not be walked.
3130 If F returns a nonzero value, the traversal ceases, and that value
3131 is returned. Otherwise, returns zero. */
3134 walk_subobject_offsets (tree type,
3135 subobject_offset_fn f,
3142 tree type_binfo = NULL_TREE;
3144 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3146 if (max_offset && INT_CST_LT (max_offset, offset))
3149 if (type == error_mark_node)
3154 if (abi_version_at_least (2))
3156 type = BINFO_TYPE (type);
3159 if (CLASS_TYPE_P (type))
3165 /* Avoid recursing into objects that are not interesting. */
3166 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3169 /* Record the location of TYPE. */
3170 r = (*f) (type, offset, offsets);
3174 /* Iterate through the direct base classes of TYPE. */
3176 type_binfo = TYPE_BINFO (type);
3177 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3181 if (abi_version_at_least (2)
3182 && BINFO_VIRTUAL_P (binfo))
3186 && BINFO_VIRTUAL_P (binfo)
3187 && !BINFO_PRIMARY_P (binfo))
3190 if (!abi_version_at_least (2))
3191 binfo_offset = size_binop (PLUS_EXPR,
3193 BINFO_OFFSET (binfo));
3197 /* We cannot rely on BINFO_OFFSET being set for the base
3198 class yet, but the offsets for direct non-virtual
3199 bases can be calculated by going back to the TYPE. */
3200 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3201 binfo_offset = size_binop (PLUS_EXPR,
3203 BINFO_OFFSET (orig_binfo));
3206 r = walk_subobject_offsets (binfo,
3211 (abi_version_at_least (2)
3212 ? /*vbases_p=*/0 : vbases_p));
3217 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3220 VEC(tree,gc) *vbases;
3222 /* Iterate through the virtual base classes of TYPE. In G++
3223 3.2, we included virtual bases in the direct base class
3224 loop above, which results in incorrect results; the
3225 correct offsets for virtual bases are only known when
3226 working with the most derived type. */
3228 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3229 VEC_iterate (tree, vbases, ix, binfo); ix++)
3231 r = walk_subobject_offsets (binfo,
3233 size_binop (PLUS_EXPR,
3235 BINFO_OFFSET (binfo)),
3244 /* We still have to walk the primary base, if it is
3245 virtual. (If it is non-virtual, then it was walked
3247 tree vbase = get_primary_binfo (type_binfo);
3249 if (vbase && BINFO_VIRTUAL_P (vbase)
3250 && BINFO_PRIMARY_P (vbase)
3251 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3253 r = (walk_subobject_offsets
3255 offsets, max_offset, /*vbases_p=*/0));
3262 /* Iterate through the fields of TYPE. */
3263 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3264 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3268 if (abi_version_at_least (2))
3269 field_offset = byte_position (field);
3271 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3272 field_offset = DECL_FIELD_OFFSET (field);
3274 r = walk_subobject_offsets (TREE_TYPE (field),
3276 size_binop (PLUS_EXPR,
3286 else if (TREE_CODE (type) == ARRAY_TYPE)
3288 tree element_type = strip_array_types (type);
3289 tree domain = TYPE_DOMAIN (type);
3292 /* Avoid recursing into objects that are not interesting. */
3293 if (!CLASS_TYPE_P (element_type)
3294 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3297 /* Step through each of the elements in the array. */
3298 for (index = size_zero_node;
3299 /* G++ 3.2 had an off-by-one error here. */
3300 (abi_version_at_least (2)
3301 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3302 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3303 index = size_binop (PLUS_EXPR, index, size_one_node))
3305 r = walk_subobject_offsets (TREE_TYPE (type),
3313 offset = size_binop (PLUS_EXPR, offset,
3314 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3315 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3316 there's no point in iterating through the remaining
3317 elements of the array. */
3318 if (max_offset && INT_CST_LT (max_offset, offset))
3326 /* Record all of the empty subobjects of TYPE (either a type or a
3327 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3328 is being placed at OFFSET; otherwise, it is a base class that is
3329 being placed at OFFSET. */
3332 record_subobject_offsets (tree type,
3335 bool is_data_member)
3338 /* If recording subobjects for a non-static data member or a
3339 non-empty base class , we do not need to record offsets beyond
3340 the size of the biggest empty class. Additional data members
3341 will go at the end of the class. Additional base classes will go
3342 either at offset zero (if empty, in which case they cannot
3343 overlap with offsets past the size of the biggest empty class) or
3344 at the end of the class.
3346 However, if we are placing an empty base class, then we must record
3347 all offsets, as either the empty class is at offset zero (where
3348 other empty classes might later be placed) or at the end of the
3349 class (where other objects might then be placed, so other empty
3350 subobjects might later overlap). */
3352 || !is_empty_class (BINFO_TYPE (type)))
3353 max_offset = sizeof_biggest_empty_class;
3355 max_offset = NULL_TREE;
3356 walk_subobject_offsets (type, record_subobject_offset, offset,
3357 offsets, max_offset, is_data_member);
3360 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3361 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3362 virtual bases of TYPE are examined. */
3365 layout_conflict_p (tree type,
3370 splay_tree_node max_node;
3372 /* Get the node in OFFSETS that indicates the maximum offset where
3373 an empty subobject is located. */
3374 max_node = splay_tree_max (offsets);
3375 /* If there aren't any empty subobjects, then there's no point in
3376 performing this check. */
3380 return walk_subobject_offsets (type, check_subobject_offset, offset,
3381 offsets, (tree) (max_node->key),
3385 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3386 non-static data member of the type indicated by RLI. BINFO is the
3387 binfo corresponding to the base subobject, OFFSETS maps offsets to
3388 types already located at those offsets. This function determines
3389 the position of the DECL. */
3392 layout_nonempty_base_or_field (record_layout_info rli,
3397 tree offset = NULL_TREE;
3403 /* For the purposes of determining layout conflicts, we want to
3404 use the class type of BINFO; TREE_TYPE (DECL) will be the
3405 CLASSTYPE_AS_BASE version, which does not contain entries for
3406 zero-sized bases. */
3407 type = TREE_TYPE (binfo);
3412 type = TREE_TYPE (decl);
3416 /* Try to place the field. It may take more than one try if we have
3417 a hard time placing the field without putting two objects of the
3418 same type at the same address. */
3421 struct record_layout_info_s old_rli = *rli;
3423 /* Place this field. */
3424 place_field (rli, decl);
3425 offset = byte_position (decl);
3427 /* We have to check to see whether or not there is already
3428 something of the same type at the offset we're about to use.
3429 For example, consider:
3432 struct T : public S { int i; };
3433 struct U : public S, public T {};
3435 Here, we put S at offset zero in U. Then, we can't put T at
3436 offset zero -- its S component would be at the same address
3437 as the S we already allocated. So, we have to skip ahead.
3438 Since all data members, including those whose type is an
3439 empty class, have nonzero size, any overlap can happen only
3440 with a direct or indirect base-class -- it can't happen with
3442 /* In a union, overlap is permitted; all members are placed at
3444 if (TREE_CODE (rli->t) == UNION_TYPE)
3446 /* G++ 3.2 did not check for overlaps when placing a non-empty
3448 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3450 if (layout_conflict_p (field_p ? type : binfo, offset,
3453 /* Strip off the size allocated to this field. That puts us
3454 at the first place we could have put the field with
3455 proper alignment. */
3458 /* Bump up by the alignment required for the type. */
3460 = size_binop (PLUS_EXPR, rli->bitpos,
3462 ? CLASSTYPE_ALIGN (type)
3463 : TYPE_ALIGN (type)));
3464 normalize_rli (rli);
3467 /* There was no conflict. We're done laying out this field. */
3471 /* Now that we know where it will be placed, update its
3473 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3474 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3475 this point because their BINFO_OFFSET is copied from another
3476 hierarchy. Therefore, we may not need to add the entire
3478 propagate_binfo_offsets (binfo,
3479 size_diffop (convert (ssizetype, offset),
3481 BINFO_OFFSET (binfo))));
3484 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3487 empty_base_at_nonzero_offset_p (tree type,
3489 splay_tree offsets ATTRIBUTE_UNUSED)
3491 return is_empty_class (type) && !integer_zerop (offset);
3494 /* Layout the empty base BINFO. EOC indicates the byte currently just
3495 past the end of the class, and should be correctly aligned for a
3496 class of the type indicated by BINFO; OFFSETS gives the offsets of
3497 the empty bases allocated so far. T is the most derived
3498 type. Return nonzero iff we added it at the end. */
3501 layout_empty_base (tree binfo, tree eoc, splay_tree offsets)
3504 tree basetype = BINFO_TYPE (binfo);
3507 /* This routine should only be used for empty classes. */
3508 gcc_assert (is_empty_class (basetype));
3509 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3511 if (!integer_zerop (BINFO_OFFSET (binfo)))
3513 if (abi_version_at_least (2))
3514 propagate_binfo_offsets
3515 (binfo, size_diffop (size_zero_node, BINFO_OFFSET (binfo)));
3518 "offset of empty base %qT may not be ABI-compliant and may"
3519 "change in a future version of GCC",
3520 BINFO_TYPE (binfo));
3523 /* This is an empty base class. We first try to put it at offset
3525 if (layout_conflict_p (binfo,
3526 BINFO_OFFSET (binfo),
3530 /* That didn't work. Now, we move forward from the next
3531 available spot in the class. */
3533 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3536 if (!layout_conflict_p (binfo,
3537 BINFO_OFFSET (binfo),
3540 /* We finally found a spot where there's no overlap. */
3543 /* There's overlap here, too. Bump along to the next spot. */
3544 propagate_binfo_offsets (binfo, alignment);
3550 /* Layout the base given by BINFO in the class indicated by RLI.
3551 *BASE_ALIGN is a running maximum of the alignments of
3552 any base class. OFFSETS gives the location of empty base
3553 subobjects. T is the most derived type. Return nonzero if the new
3554 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3555 *NEXT_FIELD, unless BINFO is for an empty base class.
3557 Returns the location at which the next field should be inserted. */
3560 build_base_field (record_layout_info rli, tree binfo,
3561 splay_tree offsets, tree *next_field)
3564 tree basetype = BINFO_TYPE (binfo);
3566 if (!COMPLETE_TYPE_P (basetype))
3567 /* This error is now reported in xref_tag, thus giving better
3568 location information. */
3571 /* Place the base class. */
3572 if (!is_empty_class (basetype))
3576 /* The containing class is non-empty because it has a non-empty
3578 CLASSTYPE_EMPTY_P (t) = 0;
3580 /* Create the FIELD_DECL. */
3581 decl = build_decl (FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3582 DECL_ARTIFICIAL (decl) = 1;
3583 DECL_IGNORED_P (decl) = 1;
3584 DECL_FIELD_CONTEXT (decl) = t;
3585 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3586 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3587 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3588 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3589 DECL_MODE (decl) = TYPE_MODE (basetype);
3590 DECL_FIELD_IS_BASE (decl) = 1;
3592 /* Try to place the field. It may take more than one try if we
3593 have a hard time placing the field without putting two
3594 objects of the same type at the same address. */
3595 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3596 /* Add the new FIELD_DECL to the list of fields for T. */
3597 TREE_CHAIN (decl) = *next_field;
3599 next_field = &TREE_CHAIN (decl);
3606 /* On some platforms (ARM), even empty classes will not be
3608 eoc = round_up (rli_size_unit_so_far (rli),
3609 CLASSTYPE_ALIGN_UNIT (basetype));
3610 atend = layout_empty_base (binfo, eoc, offsets);
3611 /* A nearly-empty class "has no proper base class that is empty,
3612 not morally virtual, and at an offset other than zero." */
3613 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3616 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3617 /* The check above (used in G++ 3.2) is insufficient because
3618 an empty class placed at offset zero might itself have an
3619 empty base at a nonzero offset. */
3620 else if (walk_subobject_offsets (basetype,
3621 empty_base_at_nonzero_offset_p,
3624 /*max_offset=*/NULL_TREE,
3627 if (abi_version_at_least (2))
3628 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3631 "class %qT will be considered nearly empty in a "
3632 "future version of GCC", t);
3636 /* We do not create a FIELD_DECL for empty base classes because
3637 it might overlap some other field. We want to be able to
3638 create CONSTRUCTORs for the class by iterating over the
3639 FIELD_DECLs, and the back end does not handle overlapping
3642 /* An empty virtual base causes a class to be non-empty
3643 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3644 here because that was already done when the virtual table
3645 pointer was created. */
3648 /* Record the offsets of BINFO and its base subobjects. */
3649 record_subobject_offsets (binfo,
3650 BINFO_OFFSET (binfo),
3652 /*is_data_member=*/false);
3657 /* Layout all of the non-virtual base classes. Record empty
3658 subobjects in OFFSETS. T is the most derived type. Return nonzero
3659 if the type cannot be nearly empty. The fields created
3660 corresponding to the base classes will be inserted at
3664 build_base_fields (record_layout_info rli,
3665 splay_tree offsets, tree *next_field)
3667 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3670 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3673 /* The primary base class is always allocated first. */
3674 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3675 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3676 offsets, next_field);
3678 /* Now allocate the rest of the bases. */
3679 for (i = 0; i < n_baseclasses; ++i)
3683 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3685 /* The primary base was already allocated above, so we don't
3686 need to allocate it again here. */
3687 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3690 /* Virtual bases are added at the end (a primary virtual base
3691 will have already been added). */
3692 if (BINFO_VIRTUAL_P (base_binfo))
3695 next_field = build_base_field (rli, base_binfo,
3696 offsets, next_field);
3700 /* Go through the TYPE_METHODS of T issuing any appropriate
3701 diagnostics, figuring out which methods override which other
3702 methods, and so forth. */
3705 check_methods (tree t)
3709 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3711 check_for_override (x, t);
3712 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3713 error ("initializer specified for non-virtual method %q+D", x);
3714 /* The name of the field is the original field name
3715 Save this in auxiliary field for later overloading. */
3716 if (DECL_VINDEX (x))
3718 TYPE_POLYMORPHIC_P (t) = 1;
3719 if (DECL_PURE_VIRTUAL_P (x))
3720 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3722 /* All user-declared destructors are non-trivial. */
3723 if (DECL_DESTRUCTOR_P (x))
3724 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3728 /* FN is a constructor or destructor. Clone the declaration to create
3729 a specialized in-charge or not-in-charge version, as indicated by
3733 build_clone (tree fn, tree name)
3738 /* Copy the function. */
3739 clone = copy_decl (fn);
3740 /* Remember where this function came from. */
3741 DECL_CLONED_FUNCTION (clone) = fn;
3742 DECL_ABSTRACT_ORIGIN (clone) = fn;
3743 /* Reset the function name. */
3744 DECL_NAME (clone) = name;
3745 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3746 /* There's no pending inline data for this function. */
3747 DECL_PENDING_INLINE_INFO (clone) = NULL;
3748 DECL_PENDING_INLINE_P (clone) = 0;
3749 /* And it hasn't yet been deferred. */
3750 DECL_DEFERRED_FN (clone) = 0;
3752 /* The base-class destructor is not virtual. */
3753 if (name == base_dtor_identifier)
3755 DECL_VIRTUAL_P (clone) = 0;
3756 if (TREE_CODE (clone) != TEMPLATE_DECL)
3757 DECL_VINDEX (clone) = NULL_TREE;
3760 /* If there was an in-charge parameter, drop it from the function
3762 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3768 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3769 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3770 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3771 /* Skip the `this' parameter. */
3772 parmtypes = TREE_CHAIN (parmtypes);
3773 /* Skip the in-charge parameter. */
3774 parmtypes = TREE_CHAIN (parmtypes);
3775 /* And the VTT parm, in a complete [cd]tor. */
3776 if (DECL_HAS_VTT_PARM_P (fn)
3777 && ! DECL_NEEDS_VTT_PARM_P (clone))
3778 parmtypes = TREE_CHAIN (parmtypes);
3779 /* If this is subobject constructor or destructor, add the vtt
3782 = build_method_type_directly (basetype,
3783 TREE_TYPE (TREE_TYPE (clone)),
3786 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3789 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3790 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3793 /* Copy the function parameters. But, DECL_ARGUMENTS on a TEMPLATE_DECL
3794 aren't function parameters; those are the template parameters. */
3795 if (TREE_CODE (clone) != TEMPLATE_DECL)
3797 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3798 /* Remove the in-charge parameter. */
3799 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3801 TREE_CHAIN (DECL_ARGUMENTS (clone))
3802 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3803 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3805 /* And the VTT parm, in a complete [cd]tor. */
3806 if (DECL_HAS_VTT_PARM_P (fn))
3808 if (DECL_NEEDS_VTT_PARM_P (clone))
3809 DECL_HAS_VTT_PARM_P (clone) = 1;
3812 TREE_CHAIN (DECL_ARGUMENTS (clone))
3813 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3814 DECL_HAS_VTT_PARM_P (clone) = 0;
3818 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3820 DECL_CONTEXT (parms) = clone;
3821 cxx_dup_lang_specific_decl (parms);
3825 /* Create the RTL for this function. */
3826 SET_DECL_RTL (clone, NULL_RTX);
3827 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3829 /* Make it easy to find the CLONE given the FN. */
3830 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3831 TREE_CHAIN (fn) = clone;
3833 /* If this is a template, handle the DECL_TEMPLATE_RESULT as well. */
3834 if (TREE_CODE (clone) == TEMPLATE_DECL)
3838 DECL_TEMPLATE_RESULT (clone)
3839 = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3840 result = DECL_TEMPLATE_RESULT (clone);
3841 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3842 DECL_TI_TEMPLATE (result) = clone;
3845 note_decl_for_pch (clone);
3850 /* Produce declarations for all appropriate clones of FN. If
3851 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
3852 CLASTYPE_METHOD_VEC as well. */
3855 clone_function_decl (tree fn, int update_method_vec_p)
3859 /* Avoid inappropriate cloning. */
3861 && DECL_CLONED_FUNCTION (TREE_CHAIN (fn)))
3864 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
3866 /* For each constructor, we need two variants: an in-charge version
3867 and a not-in-charge version. */
3868 clone = build_clone (fn, complete_ctor_identifier);
3869 if (update_method_vec_p)
3870 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3871 clone = build_clone (fn, base_ctor_identifier);
3872 if (update_method_vec_p)
3873 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3877 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
3879 /* For each destructor, we need three variants: an in-charge
3880 version, a not-in-charge version, and an in-charge deleting
3881 version. We clone the deleting version first because that
3882 means it will go second on the TYPE_METHODS list -- and that
3883 corresponds to the correct layout order in the virtual
3886 For a non-virtual destructor, we do not build a deleting
3888 if (DECL_VIRTUAL_P (fn))
3890 clone = build_clone (fn, deleting_dtor_identifier);
3891 if (update_method_vec_p)
3892 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3894 clone = build_clone (fn, complete_dtor_identifier);
3895 if (update_method_vec_p)
3896 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3897 clone = build_clone (fn, base_dtor_identifier);
3898 if (update_method_vec_p)
3899 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3902 /* Note that this is an abstract function that is never emitted. */
3903 DECL_ABSTRACT (fn) = 1;
3906 /* DECL is an in charge constructor, which is being defined. This will
3907 have had an in class declaration, from whence clones were
3908 declared. An out-of-class definition can specify additional default
3909 arguments. As it is the clones that are involved in overload
3910 resolution, we must propagate the information from the DECL to its
3914 adjust_clone_args (tree decl)
3918 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION (clone);
3919 clone = TREE_CHAIN (clone))
3921 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
3922 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
3923 tree decl_parms, clone_parms;
3925 clone_parms = orig_clone_parms;
3927 /* Skip the 'this' parameter. */
3928 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
3929 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3931 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
3932 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3933 if (DECL_HAS_VTT_PARM_P (decl))
3934 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3936 clone_parms = orig_clone_parms;
3937 if (DECL_HAS_VTT_PARM_P (clone))
3938 clone_parms = TREE_CHAIN (clone_parms);
3940 for (decl_parms = orig_decl_parms; decl_parms;
3941 decl_parms = TREE_CHAIN (decl_parms),
3942 clone_parms = TREE_CHAIN (clone_parms))
3944 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
3945 TREE_TYPE (clone_parms)));
3947 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
3949 /* A default parameter has been added. Adjust the
3950 clone's parameters. */
3951 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3952 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3955 clone_parms = orig_decl_parms;
3957 if (DECL_HAS_VTT_PARM_P (clone))
3959 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
3960 TREE_VALUE (orig_clone_parms),
3962 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
3964 type = build_method_type_directly (basetype,
3965 TREE_TYPE (TREE_TYPE (clone)),
3968 type = build_exception_variant (type, exceptions);
3969 TREE_TYPE (clone) = type;
3971 clone_parms = NULL_TREE;
3975 gcc_assert (!clone_parms);
3979 /* For each of the constructors and destructors in T, create an
3980 in-charge and not-in-charge variant. */
3983 clone_constructors_and_destructors (tree t)
3987 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
3989 if (!CLASSTYPE_METHOD_VEC (t))
3992 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
3993 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
3994 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
3995 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
3998 /* Remove all zero-width bit-fields from T. */
4001 remove_zero_width_bit_fields (tree t)
4005 fieldsp = &TYPE_FIELDS (t);
4008 if (TREE_CODE (*fieldsp) == FIELD_DECL
4009 && DECL_C_BIT_FIELD (*fieldsp)
4010 && DECL_INITIAL (*fieldsp))
4011 *fieldsp = TREE_CHAIN (*fieldsp);
4013 fieldsp = &TREE_CHAIN (*fieldsp);
4017 /* Returns TRUE iff we need a cookie when dynamically allocating an
4018 array whose elements have the indicated class TYPE. */
4021 type_requires_array_cookie (tree type)
4024 bool has_two_argument_delete_p = false;
4026 gcc_assert (CLASS_TYPE_P (type));
4028 /* If there's a non-trivial destructor, we need a cookie. In order
4029 to iterate through the array calling the destructor for each
4030 element, we'll have to know how many elements there are. */
4031 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4034 /* If the usual deallocation function is a two-argument whose second
4035 argument is of type `size_t', then we have to pass the size of
4036 the array to the deallocation function, so we will need to store
4038 fns = lookup_fnfields (TYPE_BINFO (type),
4039 ansi_opname (VEC_DELETE_EXPR),
4041 /* If there are no `operator []' members, or the lookup is
4042 ambiguous, then we don't need a cookie. */
4043 if (!fns || fns == error_mark_node)
4045 /* Loop through all of the functions. */
4046 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4051 /* Select the current function. */
4052 fn = OVL_CURRENT (fns);
4053 /* See if this function is a one-argument delete function. If
4054 it is, then it will be the usual deallocation function. */
4055 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4056 if (second_parm == void_list_node)
4058 /* Otherwise, if we have a two-argument function and the second
4059 argument is `size_t', it will be the usual deallocation
4060 function -- unless there is one-argument function, too. */
4061 if (TREE_CHAIN (second_parm) == void_list_node
4062 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4063 has_two_argument_delete_p = true;
4066 return has_two_argument_delete_p;
4069 /* Check the validity of the bases and members declared in T. Add any
4070 implicitly-generated functions (like copy-constructors and
4071 assignment operators). Compute various flag bits (like
4072 CLASSTYPE_NON_POD_T) for T. This routine works purely at the C++
4073 level: i.e., independently of the ABI in use. */
4076 check_bases_and_members (tree t)
4078 /* Nonzero if the implicitly generated copy constructor should take
4079 a non-const reference argument. */
4080 int cant_have_const_ctor;
4081 /* Nonzero if the implicitly generated assignment operator
4082 should take a non-const reference argument. */
4083 int no_const_asn_ref;
4086 /* By default, we use const reference arguments and generate default
4088 cant_have_const_ctor = 0;
4089 no_const_asn_ref = 0;
4091 /* Check all the base-classes. */
4092 check_bases (t, &cant_have_const_ctor,
4095 /* Check all the method declarations. */
4098 /* Check all the data member declarations. We cannot call
4099 check_field_decls until we have called check_bases check_methods,
4100 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4101 being set appropriately. */
4102 check_field_decls (t, &access_decls,
4103 &cant_have_const_ctor,
4106 /* A nearly-empty class has to be vptr-containing; a nearly empty
4107 class contains just a vptr. */
4108 if (!TYPE_CONTAINS_VPTR_P (t))
4109 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4111 /* Do some bookkeeping that will guide the generation of implicitly
4112 declared member functions. */
4113 TYPE_HAS_COMPLEX_INIT_REF (t)
4114 |= (TYPE_HAS_INIT_REF (t) || TYPE_CONTAINS_VPTR_P (t));
4115 TYPE_NEEDS_CONSTRUCTING (t)
4116 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_CONTAINS_VPTR_P (t));
4117 CLASSTYPE_NON_AGGREGATE (t)
4118 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_POLYMORPHIC_P (t));
4119 CLASSTYPE_NON_POD_P (t)
4120 |= (CLASSTYPE_NON_AGGREGATE (t)
4121 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
4122 || TYPE_HAS_ASSIGN_REF (t));
4123 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
4124 |= TYPE_HAS_ASSIGN_REF (t) || TYPE_CONTAINS_VPTR_P (t);
4125 TYPE_HAS_COMPLEX_DFLT (t)
4126 |= (TYPE_HAS_DEFAULT_CONSTRUCTOR (t) || TYPE_CONTAINS_VPTR_P (t));
4128 /* Synthesize any needed methods. */
4129 add_implicitly_declared_members (t,
4130 cant_have_const_ctor,
4133 /* Create the in-charge and not-in-charge variants of constructors
4135 clone_constructors_and_destructors (t);
4137 /* Process the using-declarations. */
4138 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4139 handle_using_decl (TREE_VALUE (access_decls), t);
4141 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4142 finish_struct_methods (t);
4144 /* Figure out whether or not we will need a cookie when dynamically
4145 allocating an array of this type. */
4146 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4147 = type_requires_array_cookie (t);
4150 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4151 accordingly. If a new vfield was created (because T doesn't have a
4152 primary base class), then the newly created field is returned. It
4153 is not added to the TYPE_FIELDS list; it is the caller's
4154 responsibility to do that. Accumulate declared virtual functions
4158 create_vtable_ptr (tree t, tree* virtuals_p)
4162 /* Collect the virtual functions declared in T. */
4163 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4164 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4165 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4167 tree new_virtual = make_node (TREE_LIST);
4169 BV_FN (new_virtual) = fn;
4170 BV_DELTA (new_virtual) = integer_zero_node;
4171 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4173 TREE_CHAIN (new_virtual) = *virtuals_p;
4174 *virtuals_p = new_virtual;
4177 /* If we couldn't find an appropriate base class, create a new field
4178 here. Even if there weren't any new virtual functions, we might need a
4179 new virtual function table if we're supposed to include vptrs in
4180 all classes that need them. */
4181 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4183 /* We build this decl with vtbl_ptr_type_node, which is a
4184 `vtable_entry_type*'. It might seem more precise to use
4185 `vtable_entry_type (*)[N]' where N is the number of virtual
4186 functions. However, that would require the vtable pointer in
4187 base classes to have a different type than the vtable pointer
4188 in derived classes. We could make that happen, but that
4189 still wouldn't solve all the problems. In particular, the
4190 type-based alias analysis code would decide that assignments
4191 to the base class vtable pointer can't alias assignments to
4192 the derived class vtable pointer, since they have different
4193 types. Thus, in a derived class destructor, where the base
4194 class constructor was inlined, we could generate bad code for
4195 setting up the vtable pointer.
4197 Therefore, we use one type for all vtable pointers. We still
4198 use a type-correct type; it's just doesn't indicate the array
4199 bounds. That's better than using `void*' or some such; it's
4200 cleaner, and it let's the alias analysis code know that these
4201 stores cannot alias stores to void*! */
4204 field = build_decl (FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4205 DECL_VIRTUAL_P (field) = 1;
4206 DECL_ARTIFICIAL (field) = 1;
4207 DECL_FIELD_CONTEXT (field) = t;
4208 DECL_FCONTEXT (field) = t;
4210 TYPE_VFIELD (t) = field;
4212 /* This class is non-empty. */
4213 CLASSTYPE_EMPTY_P (t) = 0;
4221 /* Fixup the inline function given by INFO now that the class is
4225 fixup_pending_inline (tree fn)
4227 if (DECL_PENDING_INLINE_INFO (fn))
4229 tree args = DECL_ARGUMENTS (fn);
4232 DECL_CONTEXT (args) = fn;
4233 args = TREE_CHAIN (args);
4238 /* Fixup the inline methods and friends in TYPE now that TYPE is
4242 fixup_inline_methods (tree type)
4244 tree method = TYPE_METHODS (type);
4245 VEC(tree,gc) *friends;
4248 if (method && TREE_CODE (method) == TREE_VEC)
4250 if (TREE_VEC_ELT (method, 1))
4251 method = TREE_VEC_ELT (method, 1);
4252 else if (TREE_VEC_ELT (method, 0))
4253 method = TREE_VEC_ELT (method, 0);
4255 method = TREE_VEC_ELT (method, 2);
4258 /* Do inline member functions. */
4259 for (; method; method = TREE_CHAIN (method))
4260 fixup_pending_inline (method);
4263 for (friends = CLASSTYPE_INLINE_FRIENDS (type), ix = 0;
4264 VEC_iterate (tree, friends, ix, method); ix++)
4265 fixup_pending_inline (method);
4266 CLASSTYPE_INLINE_FRIENDS (type) = NULL;
4269 /* Add OFFSET to all base types of BINFO which is a base in the
4270 hierarchy dominated by T.
4272 OFFSET, which is a type offset, is number of bytes. */
4275 propagate_binfo_offsets (tree binfo, tree offset)
4281 /* Update BINFO's offset. */
4282 BINFO_OFFSET (binfo)
4283 = convert (sizetype,
4284 size_binop (PLUS_EXPR,
4285 convert (ssizetype, BINFO_OFFSET (binfo)),
4288 /* Find the primary base class. */
4289 primary_binfo = get_primary_binfo (binfo);
4291 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4292 propagate_binfo_offsets (primary_binfo, offset);
4294 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4296 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4298 /* Don't do the primary base twice. */
4299 if (base_binfo == primary_binfo)
4302 if (BINFO_VIRTUAL_P (base_binfo))
4305 propagate_binfo_offsets (base_binfo, offset);
4309 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4310 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4311 empty subobjects of T. */
4314 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4318 bool first_vbase = true;
4321 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4324 if (!abi_version_at_least(2))
4326 /* In G++ 3.2, we incorrectly rounded the size before laying out
4327 the virtual bases. */
4328 finish_record_layout (rli, /*free_p=*/false);
4329 #ifdef STRUCTURE_SIZE_BOUNDARY
4330 /* Packed structures don't need to have minimum size. */
4331 if (! TYPE_PACKED (t))
4332 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4334 rli->offset = TYPE_SIZE_UNIT (t);
4335 rli->bitpos = bitsize_zero_node;
4336 rli->record_align = TYPE_ALIGN (t);
4339 /* Find the last field. The artificial fields created for virtual
4340 bases will go after the last extant field to date. */
4341 next_field = &TYPE_FIELDS (t);
4343 next_field = &TREE_CHAIN (*next_field);
4345 /* Go through the virtual bases, allocating space for each virtual
4346 base that is not already a primary base class. These are
4347 allocated in inheritance graph order. */
4348 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4350 if (!BINFO_VIRTUAL_P (vbase))
4353 if (!BINFO_PRIMARY_P (vbase))
4355 tree basetype = TREE_TYPE (vbase);
4357 /* This virtual base is not a primary base of any class in the
4358 hierarchy, so we have to add space for it. */
4359 next_field = build_base_field (rli, vbase,
4360 offsets, next_field);
4362 /* If the first virtual base might have been placed at a
4363 lower address, had we started from CLASSTYPE_SIZE, rather
4364 than TYPE_SIZE, issue a warning. There can be both false
4365 positives and false negatives from this warning in rare
4366 cases; to deal with all the possibilities would probably
4367 require performing both layout algorithms and comparing
4368 the results which is not particularly tractable. */
4372 (size_binop (CEIL_DIV_EXPR,
4373 round_up (CLASSTYPE_SIZE (t),
4374 CLASSTYPE_ALIGN (basetype)),
4376 BINFO_OFFSET (vbase))))
4378 "offset of virtual base %qT is not ABI-compliant and "
4379 "may change in a future version of GCC",
4382 first_vbase = false;
4387 /* Returns the offset of the byte just past the end of the base class
4391 end_of_base (tree binfo)
4395 if (is_empty_class (BINFO_TYPE (binfo)))
4396 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4397 allocate some space for it. It cannot have virtual bases, so
4398 TYPE_SIZE_UNIT is fine. */
4399 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4401 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4403 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4406 /* Returns the offset of the byte just past the end of the base class
4407 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4408 only non-virtual bases are included. */
4411 end_of_class (tree t, int include_virtuals_p)
4413 tree result = size_zero_node;
4414 VEC(tree,gc) *vbases;
4420 for (binfo = TYPE_BINFO (t), i = 0;
4421 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4423 if (!include_virtuals_p
4424 && BINFO_VIRTUAL_P (base_binfo)
4425 && (!BINFO_PRIMARY_P (base_binfo)
4426 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4429 offset = end_of_base (base_binfo);
4430 if (INT_CST_LT_UNSIGNED (result, offset))
4434 /* G++ 3.2 did not check indirect virtual bases. */
4435 if (abi_version_at_least (2) && include_virtuals_p)
4436 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4437 VEC_iterate (tree, vbases, i, base_binfo); i++)
4439 offset = end_of_base (base_binfo);
4440 if (INT_CST_LT_UNSIGNED (result, offset))
4447 /* Warn about bases of T that are inaccessible because they are
4448 ambiguous. For example:
4451 struct T : public S {};
4452 struct U : public S, public T {};
4454 Here, `(S*) new U' is not allowed because there are two `S'
4458 warn_about_ambiguous_bases (tree t)
4461 VEC(tree,gc) *vbases;
4466 /* If there are no repeated bases, nothing can be ambiguous. */
4467 if (!CLASSTYPE_REPEATED_BASE_P (t))
4470 /* Check direct bases. */
4471 for (binfo = TYPE_BINFO (t), i = 0;
4472 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4474 basetype = BINFO_TYPE (base_binfo);
4476 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4477 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4481 /* Check for ambiguous virtual bases. */
4483 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4484 VEC_iterate (tree, vbases, i, binfo); i++)
4486 basetype = BINFO_TYPE (binfo);
4488 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4489 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4494 /* Compare two INTEGER_CSTs K1 and K2. */
4497 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4499 return tree_int_cst_compare ((tree) k1, (tree) k2);
4502 /* Increase the size indicated in RLI to account for empty classes
4503 that are "off the end" of the class. */
4506 include_empty_classes (record_layout_info rli)
4511 /* It might be the case that we grew the class to allocate a
4512 zero-sized base class. That won't be reflected in RLI, yet,
4513 because we are willing to overlay multiple bases at the same
4514 offset. However, now we need to make sure that RLI is big enough
4515 to reflect the entire class. */
4516 eoc = end_of_class (rli->t,
4517 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4518 rli_size = rli_size_unit_so_far (rli);
4519 if (TREE_CODE (rli_size) == INTEGER_CST
4520 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4522 if (!abi_version_at_least (2))
4523 /* In version 1 of the ABI, the size of a class that ends with
4524 a bitfield was not rounded up to a whole multiple of a
4525 byte. Because rli_size_unit_so_far returns only the number
4526 of fully allocated bytes, any extra bits were not included
4528 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4530 /* The size should have been rounded to a whole byte. */
4531 gcc_assert (tree_int_cst_equal
4532 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4534 = size_binop (PLUS_EXPR,
4536 size_binop (MULT_EXPR,
4537 convert (bitsizetype,
4538 size_binop (MINUS_EXPR,
4540 bitsize_int (BITS_PER_UNIT)));
4541 normalize_rli (rli);
4545 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4546 BINFO_OFFSETs for all of the base-classes. Position the vtable
4547 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4550 layout_class_type (tree t, tree *virtuals_p)
4552 tree non_static_data_members;
4555 record_layout_info rli;
4556 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4557 types that appear at that offset. */
4558 splay_tree empty_base_offsets;
4559 /* True if the last field layed out was a bit-field. */
4560 bool last_field_was_bitfield = false;
4561 /* The location at which the next field should be inserted. */
4563 /* T, as a base class. */
4566 /* Keep track of the first non-static data member. */
4567 non_static_data_members = TYPE_FIELDS (t);
4569 /* Start laying out the record. */
4570 rli = start_record_layout (t);
4572 /* Mark all the primary bases in the hierarchy. */
4573 determine_primary_bases (t);
4575 /* Create a pointer to our virtual function table. */
4576 vptr = create_vtable_ptr (t, virtuals_p);
4578 /* The vptr is always the first thing in the class. */
4581 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4582 TYPE_FIELDS (t) = vptr;
4583 next_field = &TREE_CHAIN (vptr);
4584 place_field (rli, vptr);
4587 next_field = &TYPE_FIELDS (t);
4589 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4590 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4592 build_base_fields (rli, empty_base_offsets, next_field);
4594 /* Layout the non-static data members. */
4595 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4600 /* We still pass things that aren't non-static data members to
4601 the back end, in case it wants to do something with them. */
4602 if (TREE_CODE (field) != FIELD_DECL)
4604 place_field (rli, field);
4605 /* If the static data member has incomplete type, keep track
4606 of it so that it can be completed later. (The handling
4607 of pending statics in finish_record_layout is
4608 insufficient; consider:
4611 struct S2 { static S1 s1; };
4613 At this point, finish_record_layout will be called, but
4614 S1 is still incomplete.) */
4615 if (TREE_CODE (field) == VAR_DECL)
4617 maybe_register_incomplete_var (field);
4618 /* The visibility of static data members is determined
4619 at their point of declaration, not their point of
4621 determine_visibility (field);
4626 type = TREE_TYPE (field);
4627 if (type == error_mark_node)
4630 padding = NULL_TREE;
4632 /* If this field is a bit-field whose width is greater than its
4633 type, then there are some special rules for allocating
4635 if (DECL_C_BIT_FIELD (field)
4636 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4638 integer_type_kind itk;
4640 bool was_unnamed_p = false;
4641 /* We must allocate the bits as if suitably aligned for the
4642 longest integer type that fits in this many bits. type
4643 of the field. Then, we are supposed to use the left over
4644 bits as additional padding. */
4645 for (itk = itk_char; itk != itk_none; ++itk)
4646 if (INT_CST_LT (DECL_SIZE (field),
4647 TYPE_SIZE (integer_types[itk])))
4650 /* ITK now indicates a type that is too large for the
4651 field. We have to back up by one to find the largest
4653 integer_type = integer_types[itk - 1];
4655 /* Figure out how much additional padding is required. GCC
4656 3.2 always created a padding field, even if it had zero
4658 if (!abi_version_at_least (2)
4659 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4661 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4662 /* In a union, the padding field must have the full width
4663 of the bit-field; all fields start at offset zero. */
4664 padding = DECL_SIZE (field);
4667 if (TREE_CODE (t) == UNION_TYPE)
4668 warning (OPT_Wabi, "size assigned to %qT may not be "
4669 "ABI-compliant and may change in a future "
4672 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4673 TYPE_SIZE (integer_type));
4676 #ifdef PCC_BITFIELD_TYPE_MATTERS
4677 /* An unnamed bitfield does not normally affect the
4678 alignment of the containing class on a target where
4679 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4680 make any exceptions for unnamed bitfields when the
4681 bitfields are longer than their types. Therefore, we
4682 temporarily give the field a name. */
4683 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4685 was_unnamed_p = true;
4686 DECL_NAME (field) = make_anon_name ();
4689 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4690 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4691 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4692 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4693 empty_base_offsets);
4695 DECL_NAME (field) = NULL_TREE;
4696 /* Now that layout has been performed, set the size of the
4697 field to the size of its declared type; the rest of the
4698 field is effectively invisible. */
4699 DECL_SIZE (field) = TYPE_SIZE (type);
4700 /* We must also reset the DECL_MODE of the field. */
4701 if (abi_version_at_least (2))
4702 DECL_MODE (field) = TYPE_MODE (type);
4704 && DECL_MODE (field) != TYPE_MODE (type))
4705 /* Versions of G++ before G++ 3.4 did not reset the
4708 "the offset of %qD may not be ABI-compliant and may "
4709 "change in a future version of GCC", field);
4712 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4713 empty_base_offsets);
4715 /* Remember the location of any empty classes in FIELD. */
4716 if (abi_version_at_least (2))
4717 record_subobject_offsets (TREE_TYPE (field),
4718 byte_position(field),
4720 /*is_data_member=*/true);
4722 /* If a bit-field does not immediately follow another bit-field,
4723 and yet it starts in the middle of a byte, we have failed to
4724 comply with the ABI. */
4726 && DECL_C_BIT_FIELD (field)
4727 /* The TREE_NO_WARNING flag gets set by Objective-C when
4728 laying out an Objective-C class. The ObjC ABI differs
4729 from the C++ ABI, and so we do not want a warning
4731 && !TREE_NO_WARNING (field)
4732 && !last_field_was_bitfield
4733 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
4734 DECL_FIELD_BIT_OFFSET (field),
4735 bitsize_unit_node)))
4736 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
4737 "change in a future version of GCC", field);
4739 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
4740 offset of the field. */
4742 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
4743 byte_position (field))
4744 && contains_empty_class_p (TREE_TYPE (field)))
4745 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
4746 "classes to be placed at different locations in a "
4747 "future version of GCC", field);
4749 /* The middle end uses the type of expressions to determine the
4750 possible range of expression values. In order to optimize
4751 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
4752 must be made aware of the width of "i", via its type.
4754 Because C++ does not have integer types of arbitrary width,
4755 we must (for the purposes of the front end) convert from the
4756 type assigned here to the declared type of the bitfield
4757 whenever a bitfield expression is used as an rvalue.
4758 Similarly, when assigning a value to a bitfield, the value
4759 must be converted to the type given the bitfield here. */
4760 if (DECL_C_BIT_FIELD (field))
4763 unsigned HOST_WIDE_INT width;
4764 ftype = TREE_TYPE (field);
4765 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
4766 if (width != TYPE_PRECISION (ftype))
4768 = c_build_bitfield_integer_type (width,
4769 TYPE_UNSIGNED (ftype));
4772 /* If we needed additional padding after this field, add it
4778 padding_field = build_decl (FIELD_DECL,
4781 DECL_BIT_FIELD (padding_field) = 1;
4782 DECL_SIZE (padding_field) = padding;
4783 DECL_CONTEXT (padding_field) = t;
4784 DECL_ARTIFICIAL (padding_field) = 1;
4785 DECL_IGNORED_P (padding_field) = 1;
4786 layout_nonempty_base_or_field (rli, padding_field,
4788 empty_base_offsets);
4791 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
4794 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
4796 /* Make sure that we are on a byte boundary so that the size of
4797 the class without virtual bases will always be a round number
4799 rli->bitpos = round_up (rli->bitpos, BITS_PER_UNIT);
4800 normalize_rli (rli);
4803 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
4805 if (!abi_version_at_least (2))
4806 include_empty_classes(rli);
4808 /* Delete all zero-width bit-fields from the list of fields. Now
4809 that the type is laid out they are no longer important. */
4810 remove_zero_width_bit_fields (t);
4812 /* Create the version of T used for virtual bases. We do not use
4813 make_aggr_type for this version; this is an artificial type. For
4814 a POD type, we just reuse T. */
4815 if (CLASSTYPE_NON_POD_P (t) || CLASSTYPE_EMPTY_P (t))
4817 base_t = make_node (TREE_CODE (t));
4819 /* Set the size and alignment for the new type. In G++ 3.2, all
4820 empty classes were considered to have size zero when used as
4822 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
4824 TYPE_SIZE (base_t) = bitsize_zero_node;
4825 TYPE_SIZE_UNIT (base_t) = size_zero_node;
4826 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
4828 "layout of classes derived from empty class %qT "
4829 "may change in a future version of GCC",
4836 /* If the ABI version is not at least two, and the last
4837 field was a bit-field, RLI may not be on a byte
4838 boundary. In particular, rli_size_unit_so_far might
4839 indicate the last complete byte, while rli_size_so_far
4840 indicates the total number of bits used. Therefore,
4841 rli_size_so_far, rather than rli_size_unit_so_far, is
4842 used to compute TYPE_SIZE_UNIT. */
4843 eoc = end_of_class (t, /*include_virtuals_p=*/0);
4844 TYPE_SIZE_UNIT (base_t)
4845 = size_binop (MAX_EXPR,
4847 size_binop (CEIL_DIV_EXPR,
4848 rli_size_so_far (rli),
4849 bitsize_int (BITS_PER_UNIT))),
4852 = size_binop (MAX_EXPR,
4853 rli_size_so_far (rli),
4854 size_binop (MULT_EXPR,
4855 convert (bitsizetype, eoc),
4856 bitsize_int (BITS_PER_UNIT)));
4858 TYPE_ALIGN (base_t) = rli->record_align;
4859 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
4861 /* Copy the fields from T. */
4862 next_field = &TYPE_FIELDS (base_t);
4863 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4864 if (TREE_CODE (field) == FIELD_DECL)
4866 *next_field = build_decl (FIELD_DECL,
4869 DECL_CONTEXT (*next_field) = base_t;
4870 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
4871 DECL_FIELD_BIT_OFFSET (*next_field)
4872 = DECL_FIELD_BIT_OFFSET (field);
4873 DECL_SIZE (*next_field) = DECL_SIZE (field);
4874 DECL_MODE (*next_field) = DECL_MODE (field);
4875 next_field = &TREE_CHAIN (*next_field);
4878 /* Record the base version of the type. */
4879 CLASSTYPE_AS_BASE (t) = base_t;
4880 TYPE_CONTEXT (base_t) = t;
4883 CLASSTYPE_AS_BASE (t) = t;
4885 /* Every empty class contains an empty class. */
4886 if (CLASSTYPE_EMPTY_P (t))
4887 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
4889 /* Set the TYPE_DECL for this type to contain the right
4890 value for DECL_OFFSET, so that we can use it as part
4891 of a COMPONENT_REF for multiple inheritance. */
4892 layout_decl (TYPE_MAIN_DECL (t), 0);
4894 /* Now fix up any virtual base class types that we left lying
4895 around. We must get these done before we try to lay out the
4896 virtual function table. As a side-effect, this will remove the
4897 base subobject fields. */
4898 layout_virtual_bases (rli, empty_base_offsets);
4900 /* Make sure that empty classes are reflected in RLI at this
4902 include_empty_classes(rli);
4904 /* Make sure not to create any structures with zero size. */
4905 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
4907 build_decl (FIELD_DECL, NULL_TREE, char_type_node));
4909 /* Let the back end lay out the type. */
4910 finish_record_layout (rli, /*free_p=*/true);
4912 /* Warn about bases that can't be talked about due to ambiguity. */
4913 warn_about_ambiguous_bases (t);
4915 /* Now that we're done with layout, give the base fields the real types. */
4916 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4917 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
4918 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
4921 splay_tree_delete (empty_base_offsets);
4923 if (CLASSTYPE_EMPTY_P (t)
4924 && tree_int_cst_lt (sizeof_biggest_empty_class,
4925 TYPE_SIZE_UNIT (t)))
4926 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
4929 /* Determine the "key method" for the class type indicated by TYPE,
4930 and set CLASSTYPE_KEY_METHOD accordingly. */
4933 determine_key_method (tree type)
4937 if (TYPE_FOR_JAVA (type)
4938 || processing_template_decl
4939 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
4940 || CLASSTYPE_INTERFACE_KNOWN (type))
4943 /* The key method is the first non-pure virtual function that is not
4944 inline at the point of class definition. On some targets the
4945 key function may not be inline; those targets should not call
4946 this function until the end of the translation unit. */
4947 for (method = TYPE_METHODS (type); method != NULL_TREE;
4948 method = TREE_CHAIN (method))
4949 if (DECL_VINDEX (method) != NULL_TREE
4950 && ! DECL_DECLARED_INLINE_P (method)
4951 && ! DECL_PURE_VIRTUAL_P (method))
4953 CLASSTYPE_KEY_METHOD (type) = method;
4960 /* Perform processing required when the definition of T (a class type)
4964 finish_struct_1 (tree t)
4967 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
4968 tree virtuals = NULL_TREE;
4971 if (COMPLETE_TYPE_P (t))
4973 gcc_assert (IS_AGGR_TYPE (t));
4974 error ("redefinition of %q#T", t);
4979 /* If this type was previously laid out as a forward reference,
4980 make sure we lay it out again. */
4981 TYPE_SIZE (t) = NULL_TREE;
4982 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
4984 fixup_inline_methods (t);
4986 /* Make assumptions about the class; we'll reset the flags if
4988 CLASSTYPE_EMPTY_P (t) = 1;
4989 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
4990 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
4992 /* Do end-of-class semantic processing: checking the validity of the
4993 bases and members and add implicitly generated methods. */
4994 check_bases_and_members (t);
4996 /* Find the key method. */
4997 if (TYPE_CONTAINS_VPTR_P (t))
4999 /* The Itanium C++ ABI permits the key method to be chosen when
5000 the class is defined -- even though the key method so
5001 selected may later turn out to be an inline function. On
5002 some systems (such as ARM Symbian OS) the key method cannot
5003 be determined until the end of the translation unit. On such
5004 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5005 will cause the class to be added to KEYED_CLASSES. Then, in
5006 finish_file we will determine the key method. */
5007 if (targetm.cxx.key_method_may_be_inline ())
5008 determine_key_method (t);
5010 /* If a polymorphic class has no key method, we may emit the vtable
5011 in every translation unit where the class definition appears. */
5012 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5013 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5016 /* Layout the class itself. */
5017 layout_class_type (t, &virtuals);
5018 if (CLASSTYPE_AS_BASE (t) != t)
5019 /* We use the base type for trivial assignments, and hence it
5021 compute_record_mode (CLASSTYPE_AS_BASE (t));
5023 virtuals = modify_all_vtables (t, nreverse (virtuals));
5025 /* If necessary, create the primary vtable for this class. */
5026 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5028 /* We must enter these virtuals into the table. */
5029 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5030 build_primary_vtable (NULL_TREE, t);
5031 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5032 /* Here we know enough to change the type of our virtual
5033 function table, but we will wait until later this function. */
5034 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5037 if (TYPE_CONTAINS_VPTR_P (t))
5042 if (BINFO_VTABLE (TYPE_BINFO (t)))
5043 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5044 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5045 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5047 /* Add entries for virtual functions introduced by this class. */
5048 BINFO_VIRTUALS (TYPE_BINFO (t))
5049 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5051 /* Set DECL_VINDEX for all functions declared in this class. */
5052 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5054 fn = TREE_CHAIN (fn),
5055 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5056 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5058 tree fndecl = BV_FN (fn);
5060 if (DECL_THUNK_P (fndecl))
5061 /* A thunk. We should never be calling this entry directly
5062 from this vtable -- we'd use the entry for the non
5063 thunk base function. */
5064 DECL_VINDEX (fndecl) = NULL_TREE;
5065 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5066 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5070 finish_struct_bits (t);
5072 /* Complete the rtl for any static member objects of the type we're
5074 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5075 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5076 && TREE_TYPE (x) != error_mark_node
5077 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5078 DECL_MODE (x) = TYPE_MODE (t);
5080 /* Done with FIELDS...now decide whether to sort these for
5081 faster lookups later.
5083 We use a small number because most searches fail (succeeding
5084 ultimately as the search bores through the inheritance
5085 hierarchy), and we want this failure to occur quickly. */
5087 n_fields = count_fields (TYPE_FIELDS (t));
5090 struct sorted_fields_type *field_vec = GGC_NEWVAR
5091 (struct sorted_fields_type,
5092 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5093 field_vec->len = n_fields;
5094 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5095 qsort (field_vec->elts, n_fields, sizeof (tree),
5097 if (! DECL_LANG_SPECIFIC (TYPE_MAIN_DECL (t)))
5098 retrofit_lang_decl (TYPE_MAIN_DECL (t));
5099 DECL_SORTED_FIELDS (TYPE_MAIN_DECL (t)) = field_vec;
5102 /* Complain if one of the field types requires lower visibility. */
5103 constrain_class_visibility (t);
5105 /* Make the rtl for any new vtables we have created, and unmark
5106 the base types we marked. */
5109 /* Build the VTT for T. */
5112 /* This warning does not make sense for Java classes, since they
5113 cannot have destructors. */
5114 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5118 dtor = CLASSTYPE_DESTRUCTORS (t);
5119 /* Warn only if the dtor is non-private or the class has
5121 if (/* An implicitly declared destructor is always public. And,
5122 if it were virtual, we would have created it by now. */
5124 || (!DECL_VINDEX (dtor)
5125 && (!TREE_PRIVATE (dtor)
5126 || CLASSTYPE_FRIEND_CLASSES (t)
5127 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))
5128 warning (0, "%q#T has virtual functions but non-virtual destructor",
5134 if (warn_overloaded_virtual)
5137 /* Class layout, assignment of virtual table slots, etc., is now
5138 complete. Give the back end a chance to tweak the visibility of
5139 the class or perform any other required target modifications. */
5140 targetm.cxx.adjust_class_at_definition (t);
5142 maybe_suppress_debug_info (t);
5144 dump_class_hierarchy (t);
5146 /* Finish debugging output for this type. */
5147 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5150 /* When T was built up, the member declarations were added in reverse
5151 order. Rearrange them to declaration order. */
5154 unreverse_member_declarations (tree t)
5160 /* The following lists are all in reverse order. Put them in
5161 declaration order now. */
5162 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5163 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5165 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5166 reverse order, so we can't just use nreverse. */
5168 for (x = TYPE_FIELDS (t);
5169 x && TREE_CODE (x) != TYPE_DECL;
5172 next = TREE_CHAIN (x);
5173 TREE_CHAIN (x) = prev;
5178 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5180 TYPE_FIELDS (t) = prev;
5185 finish_struct (tree t, tree attributes)
5187 location_t saved_loc = input_location;
5189 /* Now that we've got all the field declarations, reverse everything
5191 unreverse_member_declarations (t);
5193 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5195 /* Nadger the current location so that diagnostics point to the start of
5196 the struct, not the end. */
5197 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5199 if (processing_template_decl)
5203 finish_struct_methods (t);
5204 TYPE_SIZE (t) = bitsize_zero_node;
5205 TYPE_SIZE_UNIT (t) = size_zero_node;
5207 /* We need to emit an error message if this type was used as a parameter
5208 and it is an abstract type, even if it is a template. We construct
5209 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5210 account and we call complete_vars with this type, which will check
5211 the PARM_DECLS. Note that while the type is being defined,
5212 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5213 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5214 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5215 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5216 if (DECL_PURE_VIRTUAL_P (x))
5217 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5221 finish_struct_1 (t);
5223 input_location = saved_loc;
5225 TYPE_BEING_DEFINED (t) = 0;
5227 if (current_class_type)
5230 error ("trying to finish struct, but kicked out due to previous parse errors");
5232 if (processing_template_decl && at_function_scope_p ())
5233 add_stmt (build_min (TAG_DEFN, t));
5238 /* Return the dynamic type of INSTANCE, if known.
5239 Used to determine whether the virtual function table is needed
5242 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5243 of our knowledge of its type. *NONNULL should be initialized
5244 before this function is called. */
5247 fixed_type_or_null (tree instance, int* nonnull, int* cdtorp)
5249 switch (TREE_CODE (instance))
5252 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5255 return fixed_type_or_null (TREE_OPERAND (instance, 0),
5259 /* This is a call to a constructor, hence it's never zero. */
5260 if (TREE_HAS_CONSTRUCTOR (instance))
5264 return TREE_TYPE (instance);
5269 /* This is a call to a constructor, hence it's never zero. */
5270 if (TREE_HAS_CONSTRUCTOR (instance))
5274 return TREE_TYPE (instance);
5276 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5280 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5281 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5282 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5283 /* Propagate nonnull. */
5284 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5289 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5292 instance = TREE_OPERAND (instance, 0);
5295 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5296 with a real object -- given &p->f, p can still be null. */
5297 tree t = get_base_address (instance);
5298 /* ??? Probably should check DECL_WEAK here. */
5299 if (t && DECL_P (t))
5302 return fixed_type_or_null (instance, nonnull, cdtorp);
5305 /* If this component is really a base class reference, then the field
5306 itself isn't definitive. */
5307 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5308 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5309 return fixed_type_or_null (TREE_OPERAND (instance, 1), nonnull, cdtorp);
5313 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5314 && IS_AGGR_TYPE (TREE_TYPE (TREE_TYPE (instance))))
5318 return TREE_TYPE (TREE_TYPE (instance));
5320 /* fall through... */
5324 if (IS_AGGR_TYPE (TREE_TYPE (instance)))
5328 return TREE_TYPE (instance);
5330 else if (instance == current_class_ptr)
5335 /* if we're in a ctor or dtor, we know our type. */
5336 if (DECL_LANG_SPECIFIC (current_function_decl)
5337 && (DECL_CONSTRUCTOR_P (current_function_decl)
5338 || DECL_DESTRUCTOR_P (current_function_decl)))
5342 return TREE_TYPE (TREE_TYPE (instance));
5345 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5347 /* Reference variables should be references to objects. */
5351 /* DECL_VAR_MARKED_P is used to prevent recursion; a
5352 variable's initializer may refer to the variable
5354 if (TREE_CODE (instance) == VAR_DECL
5355 && DECL_INITIAL (instance)
5356 && !DECL_VAR_MARKED_P (instance))
5359 DECL_VAR_MARKED_P (instance) = 1;
5360 type = fixed_type_or_null (DECL_INITIAL (instance),
5362 DECL_VAR_MARKED_P (instance) = 0;
5373 /* Return nonzero if the dynamic type of INSTANCE is known, and
5374 equivalent to the static type. We also handle the case where
5375 INSTANCE is really a pointer. Return negative if this is a
5376 ctor/dtor. There the dynamic type is known, but this might not be
5377 the most derived base of the original object, and hence virtual
5378 bases may not be layed out according to this type.
5380 Used to determine whether the virtual function table is needed
5383 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5384 of our knowledge of its type. *NONNULL should be initialized
5385 before this function is called. */
5388 resolves_to_fixed_type_p (tree instance, int* nonnull)
5390 tree t = TREE_TYPE (instance);
5393 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5394 if (fixed == NULL_TREE)
5396 if (POINTER_TYPE_P (t))
5398 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5400 return cdtorp ? -1 : 1;
5405 init_class_processing (void)
5407 current_class_depth = 0;
5408 current_class_stack_size = 10;
5410 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5411 local_classes = VEC_alloc (tree, gc, 8);
5412 sizeof_biggest_empty_class = size_zero_node;
5414 ridpointers[(int) RID_PUBLIC] = access_public_node;
5415 ridpointers[(int) RID_PRIVATE] = access_private_node;
5416 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5419 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5422 restore_class_cache (void)
5426 /* We are re-entering the same class we just left, so we don't
5427 have to search the whole inheritance matrix to find all the
5428 decls to bind again. Instead, we install the cached
5429 class_shadowed list and walk through it binding names. */
5430 push_binding_level (previous_class_level);
5431 class_binding_level = previous_class_level;
5432 /* Restore IDENTIFIER_TYPE_VALUE. */
5433 for (type = class_binding_level->type_shadowed;
5435 type = TREE_CHAIN (type))
5436 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5439 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5440 appropriate for TYPE.
5442 So that we may avoid calls to lookup_name, we cache the _TYPE
5443 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5445 For multiple inheritance, we perform a two-pass depth-first search
5446 of the type lattice. */
5449 pushclass (tree type)
5451 class_stack_node_t csn;
5453 type = TYPE_MAIN_VARIANT (type);
5455 /* Make sure there is enough room for the new entry on the stack. */
5456 if (current_class_depth + 1 >= current_class_stack_size)
5458 current_class_stack_size *= 2;
5460 = XRESIZEVEC (struct class_stack_node, current_class_stack,
5461 current_class_stack_size);
5464 /* Insert a new entry on the class stack. */
5465 csn = current_class_stack + current_class_depth;
5466 csn->name = current_class_name;
5467 csn->type = current_class_type;
5468 csn->access = current_access_specifier;
5469 csn->names_used = 0;
5471 current_class_depth++;
5473 /* Now set up the new type. */
5474 current_class_name = TYPE_NAME (type);
5475 if (TREE_CODE (current_class_name) == TYPE_DECL)
5476 current_class_name = DECL_NAME (current_class_name);
5477 current_class_type = type;
5479 /* By default, things in classes are private, while things in
5480 structures or unions are public. */
5481 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5482 ? access_private_node
5483 : access_public_node);
5485 if (previous_class_level
5486 && type != previous_class_level->this_entity
5487 && current_class_depth == 1)
5489 /* Forcibly remove any old class remnants. */
5490 invalidate_class_lookup_cache ();
5493 if (!previous_class_level
5494 || type != previous_class_level->this_entity
5495 || current_class_depth > 1)
5498 restore_class_cache ();
5501 /* When we exit a toplevel class scope, we save its binding level so
5502 that we can restore it quickly. Here, we've entered some other
5503 class, so we must invalidate our cache. */
5506 invalidate_class_lookup_cache (void)
5508 previous_class_level = NULL;
5511 /* Get out of the current class scope. If we were in a class scope
5512 previously, that is the one popped to. */
5519 current_class_depth--;
5520 current_class_name = current_class_stack[current_class_depth].name;
5521 current_class_type = current_class_stack[current_class_depth].type;
5522 current_access_specifier = current_class_stack[current_class_depth].access;
5523 if (current_class_stack[current_class_depth].names_used)
5524 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5527 /* Mark the top of the class stack as hidden. */
5530 push_class_stack (void)
5532 if (current_class_depth)
5533 ++current_class_stack[current_class_depth - 1].hidden;
5536 /* Mark the top of the class stack as un-hidden. */
5539 pop_class_stack (void)
5541 if (current_class_depth)
5542 --current_class_stack[current_class_depth - 1].hidden;
5545 /* Returns 1 if the class type currently being defined is either T or
5546 a nested type of T. */
5549 currently_open_class (tree t)
5553 /* We start looking from 1 because entry 0 is from global scope,
5555 for (i = current_class_depth; i > 0; --i)
5558 if (i == current_class_depth)
5559 c = current_class_type;
5562 if (current_class_stack[i].hidden)
5564 c = current_class_stack[i].type;
5568 if (same_type_p (c, t))
5574 /* If either current_class_type or one of its enclosing classes are derived
5575 from T, return the appropriate type. Used to determine how we found
5576 something via unqualified lookup. */
5579 currently_open_derived_class (tree t)
5583 /* The bases of a dependent type are unknown. */
5584 if (dependent_type_p (t))
5587 if (!current_class_type)
5590 if (DERIVED_FROM_P (t, current_class_type))
5591 return current_class_type;
5593 for (i = current_class_depth - 1; i > 0; --i)
5595 if (current_class_stack[i].hidden)
5597 if (DERIVED_FROM_P (t, current_class_stack[i].type))
5598 return current_class_stack[i].type;
5604 /* When entering a class scope, all enclosing class scopes' names with
5605 static meaning (static variables, static functions, types and
5606 enumerators) have to be visible. This recursive function calls
5607 pushclass for all enclosing class contexts until global or a local
5608 scope is reached. TYPE is the enclosed class. */
5611 push_nested_class (tree type)
5615 /* A namespace might be passed in error cases, like A::B:C. */
5616 if (type == NULL_TREE
5617 || type == error_mark_node
5618 || TREE_CODE (type) == NAMESPACE_DECL
5619 || ! IS_AGGR_TYPE (type)
5620 || TREE_CODE (type) == TEMPLATE_TYPE_PARM
5621 || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
5624 context = DECL_CONTEXT (TYPE_MAIN_DECL (type));
5626 if (context && CLASS_TYPE_P (context))
5627 push_nested_class (context);
5631 /* Undoes a push_nested_class call. */
5634 pop_nested_class (void)
5636 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5639 if (context && CLASS_TYPE_P (context))
5640 pop_nested_class ();
5643 /* Returns the number of extern "LANG" blocks we are nested within. */
5646 current_lang_depth (void)
5648 return VEC_length (tree, current_lang_base);
5651 /* Set global variables CURRENT_LANG_NAME to appropriate value
5652 so that behavior of name-mangling machinery is correct. */
5655 push_lang_context (tree name)
5657 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
5659 if (name == lang_name_cplusplus)
5661 current_lang_name = name;
5663 else if (name == lang_name_java)
5665 current_lang_name = name;
5666 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5667 (See record_builtin_java_type in decl.c.) However, that causes
5668 incorrect debug entries if these types are actually used.
5669 So we re-enable debug output after extern "Java". */
5670 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
5671 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
5672 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
5673 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
5674 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
5675 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
5676 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
5677 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
5679 else if (name == lang_name_c)
5681 current_lang_name = name;
5684 error ("language string %<\"%E\"%> not recognized", name);
5687 /* Get out of the current language scope. */
5690 pop_lang_context (void)
5692 current_lang_name = VEC_pop (tree, current_lang_base);
5695 /* Type instantiation routines. */
5697 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
5698 matches the TARGET_TYPE. If there is no satisfactory match, return
5699 error_mark_node, and issue an error & warning messages under
5700 control of FLAGS. Permit pointers to member function if FLAGS
5701 permits. If TEMPLATE_ONLY, the name of the overloaded function was
5702 a template-id, and EXPLICIT_TARGS are the explicitly provided
5703 template arguments. If OVERLOAD is for one or more member
5704 functions, then ACCESS_PATH is the base path used to reference
5705 those member functions. */
5708 resolve_address_of_overloaded_function (tree target_type,
5710 tsubst_flags_t flags,
5712 tree explicit_targs,
5715 /* Here's what the standard says:
5719 If the name is a function template, template argument deduction
5720 is done, and if the argument deduction succeeds, the deduced
5721 arguments are used to generate a single template function, which
5722 is added to the set of overloaded functions considered.
5724 Non-member functions and static member functions match targets of
5725 type "pointer-to-function" or "reference-to-function." Nonstatic
5726 member functions match targets of type "pointer-to-member
5727 function;" the function type of the pointer to member is used to
5728 select the member function from the set of overloaded member
5729 functions. If a nonstatic member function is selected, the
5730 reference to the overloaded function name is required to have the
5731 form of a pointer to member as described in 5.3.1.
5733 If more than one function is selected, any template functions in
5734 the set are eliminated if the set also contains a non-template
5735 function, and any given template function is eliminated if the
5736 set contains a second template function that is more specialized
5737 than the first according to the partial ordering rules 14.5.5.2.
5738 After such eliminations, if any, there shall remain exactly one
5739 selected function. */
5742 int is_reference = 0;
5743 /* We store the matches in a TREE_LIST rooted here. The functions
5744 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
5745 interoperability with most_specialized_instantiation. */
5746 tree matches = NULL_TREE;
5749 /* By the time we get here, we should be seeing only real
5750 pointer-to-member types, not the internal POINTER_TYPE to
5751 METHOD_TYPE representation. */
5752 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
5753 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
5755 gcc_assert (is_overloaded_fn (overload));
5757 /* Check that the TARGET_TYPE is reasonable. */
5758 if (TYPE_PTRFN_P (target_type))
5760 else if (TYPE_PTRMEMFUNC_P (target_type))
5761 /* This is OK, too. */
5763 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
5765 /* This is OK, too. This comes from a conversion to reference
5767 target_type = build_reference_type (target_type);
5772 if (flags & tf_error)
5773 error ("cannot resolve overloaded function %qD based on"
5774 " conversion to type %qT",
5775 DECL_NAME (OVL_FUNCTION (overload)), target_type);
5776 return error_mark_node;
5779 /* If we can find a non-template function that matches, we can just
5780 use it. There's no point in generating template instantiations
5781 if we're just going to throw them out anyhow. But, of course, we
5782 can only do this when we don't *need* a template function. */
5787 for (fns = overload; fns; fns = OVL_NEXT (fns))
5789 tree fn = OVL_CURRENT (fns);
5792 if (TREE_CODE (fn) == TEMPLATE_DECL)
5793 /* We're not looking for templates just yet. */
5796 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5798 /* We're looking for a non-static member, and this isn't
5799 one, or vice versa. */
5802 /* Ignore functions which haven't been explicitly
5804 if (DECL_ANTICIPATED (fn))
5807 /* See if there's a match. */
5808 fntype = TREE_TYPE (fn);
5810 fntype = build_ptrmemfunc_type (build_pointer_type (fntype));
5811 else if (!is_reference)
5812 fntype = build_pointer_type (fntype);
5814 if (can_convert_arg (target_type, fntype, fn, LOOKUP_NORMAL))
5815 matches = tree_cons (fn, NULL_TREE, matches);
5819 /* Now, if we've already got a match (or matches), there's no need
5820 to proceed to the template functions. But, if we don't have a
5821 match we need to look at them, too. */
5824 tree target_fn_type;
5825 tree target_arg_types;
5826 tree target_ret_type;
5831 = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (target_type));
5833 target_fn_type = TREE_TYPE (target_type);
5834 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
5835 target_ret_type = TREE_TYPE (target_fn_type);
5837 /* Never do unification on the 'this' parameter. */
5838 if (TREE_CODE (target_fn_type) == METHOD_TYPE)
5839 target_arg_types = TREE_CHAIN (target_arg_types);
5841 for (fns = overload; fns; fns = OVL_NEXT (fns))
5843 tree fn = OVL_CURRENT (fns);
5845 tree instantiation_type;
5848 if (TREE_CODE (fn) != TEMPLATE_DECL)
5849 /* We're only looking for templates. */
5852 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5854 /* We're not looking for a non-static member, and this is
5855 one, or vice versa. */
5858 /* Try to do argument deduction. */
5859 targs = make_tree_vec (DECL_NTPARMS (fn));
5860 if (fn_type_unification (fn, explicit_targs, targs,
5861 target_arg_types, target_ret_type,
5862 DEDUCE_EXACT, LOOKUP_NORMAL))
5863 /* Argument deduction failed. */
5866 /* Instantiate the template. */
5867 instantiation = instantiate_template (fn, targs, flags);
5868 if (instantiation == error_mark_node)
5869 /* Instantiation failed. */
5872 /* See if there's a match. */
5873 instantiation_type = TREE_TYPE (instantiation);
5875 instantiation_type =
5876 build_ptrmemfunc_type (build_pointer_type (instantiation_type));
5877 else if (!is_reference)
5878 instantiation_type = build_pointer_type (instantiation_type);
5879 if (can_convert_arg (target_type, instantiation_type, instantiation,
5881 matches = tree_cons (instantiation, fn, matches);
5884 /* Now, remove all but the most specialized of the matches. */
5887 tree match = most_specialized_instantiation (matches);
5889 if (match != error_mark_node)
5890 matches = tree_cons (TREE_PURPOSE (match),
5896 /* Now we should have exactly one function in MATCHES. */
5897 if (matches == NULL_TREE)
5899 /* There were *no* matches. */
5900 if (flags & tf_error)
5902 error ("no matches converting function %qD to type %q#T",
5903 DECL_NAME (OVL_FUNCTION (overload)),
5906 /* print_candidates expects a chain with the functions in
5907 TREE_VALUE slots, so we cons one up here (we're losing anyway,
5908 so why be clever?). */
5909 for (; overload; overload = OVL_NEXT (overload))
5910 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
5913 print_candidates (matches);
5915 return error_mark_node;
5917 else if (TREE_CHAIN (matches))
5919 /* There were too many matches. */
5921 if (flags & tf_error)
5925 error ("converting overloaded function %qD to type %q#T is ambiguous",
5926 DECL_NAME (OVL_FUNCTION (overload)),
5929 /* Since print_candidates expects the functions in the
5930 TREE_VALUE slot, we flip them here. */
5931 for (match = matches; match; match = TREE_CHAIN (match))
5932 TREE_VALUE (match) = TREE_PURPOSE (match);
5934 print_candidates (matches);
5937 return error_mark_node;
5940 /* Good, exactly one match. Now, convert it to the correct type. */
5941 fn = TREE_PURPOSE (matches);
5943 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
5944 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
5946 static int explained;
5948 if (!(flags & tf_error))
5949 return error_mark_node;
5951 pedwarn ("assuming pointer to member %qD", fn);
5954 pedwarn ("(a pointer to member can only be formed with %<&%E%>)", fn);
5959 /* If we're doing overload resolution purely for the purpose of
5960 determining conversion sequences, we should not consider the
5961 function used. If this conversion sequence is selected, the
5962 function will be marked as used at this point. */
5963 if (!(flags & tf_conv))
5966 /* We could not check access when this expression was originally
5967 created since we did not know at that time to which function
5968 the expression referred. */
5969 if (DECL_FUNCTION_MEMBER_P (fn))
5971 gcc_assert (access_path);
5972 perform_or_defer_access_check (access_path, fn, fn);
5976 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
5977 return build_unary_op (ADDR_EXPR, fn, 0);
5980 /* The target must be a REFERENCE_TYPE. Above, build_unary_op
5981 will mark the function as addressed, but here we must do it
5983 cxx_mark_addressable (fn);
5989 /* This function will instantiate the type of the expression given in
5990 RHS to match the type of LHSTYPE. If errors exist, then return
5991 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
5992 we complain on errors. If we are not complaining, never modify rhs,
5993 as overload resolution wants to try many possible instantiations, in
5994 the hope that at least one will work.
5996 For non-recursive calls, LHSTYPE should be a function, pointer to
5997 function, or a pointer to member function. */
6000 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6002 tsubst_flags_t flags_in = flags;
6003 tree access_path = NULL_TREE;
6005 flags &= ~tf_ptrmem_ok;
6007 if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
6009 if (flags & tf_error)
6010 error ("not enough type information");
6011 return error_mark_node;
6014 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6016 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6018 if (flag_ms_extensions
6019 && TYPE_PTRMEMFUNC_P (lhstype)
6020 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6021 /* Microsoft allows `A::f' to be resolved to a
6022 pointer-to-member. */
6026 if (flags & tf_error)
6027 error ("argument of type %qT does not match %qT",
6028 TREE_TYPE (rhs), lhstype);
6029 return error_mark_node;
6033 if (TREE_CODE (rhs) == BASELINK)
6035 access_path = BASELINK_ACCESS_BINFO (rhs);
6036 rhs = BASELINK_FUNCTIONS (rhs);
6039 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6040 deduce any type information. */
6041 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6043 if (flags & tf_error)
6044 error ("not enough type information");
6045 return error_mark_node;
6048 /* There only a few kinds of expressions that may have a type
6049 dependent on overload resolution. */
6050 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6051 || TREE_CODE (rhs) == COMPONENT_REF
6052 || TREE_CODE (rhs) == COMPOUND_EXPR
6053 || really_overloaded_fn (rhs));
6055 /* We don't overwrite rhs if it is an overloaded function.
6056 Copying it would destroy the tree link. */
6057 if (TREE_CODE (rhs) != OVERLOAD)
6058 rhs = copy_node (rhs);
6060 /* This should really only be used when attempting to distinguish
6061 what sort of a pointer to function we have. For now, any
6062 arithmetic operation which is not supported on pointers
6063 is rejected as an error. */
6065 switch (TREE_CODE (rhs))
6069 tree member = TREE_OPERAND (rhs, 1);
6071 member = instantiate_type (lhstype, member, flags);
6072 if (member != error_mark_node
6073 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6074 /* Do not lose object's side effects. */
6075 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6076 TREE_OPERAND (rhs, 0), member);
6081 rhs = TREE_OPERAND (rhs, 1);
6082 if (BASELINK_P (rhs))
6083 return instantiate_type (lhstype, rhs, flags_in);
6085 /* This can happen if we are forming a pointer-to-member for a
6087 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6091 case TEMPLATE_ID_EXPR:
6093 tree fns = TREE_OPERAND (rhs, 0);
6094 tree args = TREE_OPERAND (rhs, 1);
6097 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6098 /*template_only=*/true,
6105 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6106 /*template_only=*/false,
6107 /*explicit_targs=*/NULL_TREE,
6111 TREE_OPERAND (rhs, 0)
6112 = instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6113 if (TREE_OPERAND (rhs, 0) == error_mark_node)
6114 return error_mark_node;
6115 TREE_OPERAND (rhs, 1)
6116 = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags);
6117 if (TREE_OPERAND (rhs, 1) == error_mark_node)
6118 return error_mark_node;
6120 TREE_TYPE (rhs) = lhstype;
6125 if (PTRMEM_OK_P (rhs))
6126 flags |= tf_ptrmem_ok;
6128 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6132 return error_mark_node;
6137 return error_mark_node;
6140 /* Return the name of the virtual function pointer field
6141 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6142 this may have to look back through base types to find the
6143 ultimate field name. (For single inheritance, these could
6144 all be the same name. Who knows for multiple inheritance). */
6147 get_vfield_name (tree type)
6149 tree binfo, base_binfo;
6152 for (binfo = TYPE_BINFO (type);
6153 BINFO_N_BASE_BINFOS (binfo);
6156 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6158 if (BINFO_VIRTUAL_P (base_binfo)
6159 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6163 type = BINFO_TYPE (binfo);
6164 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6165 + TYPE_NAME_LENGTH (type) + 2);
6166 sprintf (buf, VFIELD_NAME_FORMAT,
6167 IDENTIFIER_POINTER (constructor_name (type)));
6168 return get_identifier (buf);
6172 print_class_statistics (void)
6174 #ifdef GATHER_STATISTICS
6175 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6176 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6179 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6180 n_vtables, n_vtable_searches);
6181 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6182 n_vtable_entries, n_vtable_elems);
6187 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6188 according to [class]:
6189 The class-name is also inserted
6190 into the scope of the class itself. For purposes of access checking,
6191 the inserted class name is treated as if it were a public member name. */
6194 build_self_reference (void)
6196 tree name = constructor_name (current_class_type);
6197 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6200 DECL_NONLOCAL (value) = 1;
6201 DECL_CONTEXT (value) = current_class_type;
6202 DECL_ARTIFICIAL (value) = 1;
6203 SET_DECL_SELF_REFERENCE_P (value);
6205 if (processing_template_decl)
6206 value = push_template_decl (value);
6208 saved_cas = current_access_specifier;
6209 current_access_specifier = access_public_node;
6210 finish_member_declaration (value);
6211 current_access_specifier = saved_cas;
6214 /* Returns 1 if TYPE contains only padding bytes. */
6217 is_empty_class (tree type)
6219 if (type == error_mark_node)
6222 if (! IS_AGGR_TYPE (type))
6225 /* In G++ 3.2, whether or not a class was empty was determined by
6226 looking at its size. */
6227 if (abi_version_at_least (2))
6228 return CLASSTYPE_EMPTY_P (type);
6230 return integer_zerop (CLASSTYPE_SIZE (type));
6233 /* Returns true if TYPE contains an empty class. */
6236 contains_empty_class_p (tree type)
6238 if (is_empty_class (type))
6240 if (CLASS_TYPE_P (type))
6247 for (binfo = TYPE_BINFO (type), i = 0;
6248 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6249 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6251 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6252 if (TREE_CODE (field) == FIELD_DECL
6253 && !DECL_ARTIFICIAL (field)
6254 && is_empty_class (TREE_TYPE (field)))
6257 else if (TREE_CODE (type) == ARRAY_TYPE)
6258 return contains_empty_class_p (TREE_TYPE (type));
6262 /* Note that NAME was looked up while the current class was being
6263 defined and that the result of that lookup was DECL. */
6266 maybe_note_name_used_in_class (tree name, tree decl)
6268 splay_tree names_used;
6270 /* If we're not defining a class, there's nothing to do. */
6271 if (!(innermost_scope_kind() == sk_class
6272 && TYPE_BEING_DEFINED (current_class_type)))
6275 /* If there's already a binding for this NAME, then we don't have
6276 anything to worry about. */
6277 if (lookup_member (current_class_type, name,
6278 /*protect=*/0, /*want_type=*/false))
6281 if (!current_class_stack[current_class_depth - 1].names_used)
6282 current_class_stack[current_class_depth - 1].names_used
6283 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6284 names_used = current_class_stack[current_class_depth - 1].names_used;
6286 splay_tree_insert (names_used,
6287 (splay_tree_key) name,
6288 (splay_tree_value) decl);
6291 /* Note that NAME was declared (as DECL) in the current class. Check
6292 to see that the declaration is valid. */
6295 note_name_declared_in_class (tree name, tree decl)
6297 splay_tree names_used;
6300 /* Look to see if we ever used this name. */
6302 = current_class_stack[current_class_depth - 1].names_used;
6306 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6309 /* [basic.scope.class]
6311 A name N used in a class S shall refer to the same declaration
6312 in its context and when re-evaluated in the completed scope of
6314 pedwarn ("declaration of %q#D", decl);
6315 pedwarn ("changes meaning of %qD from %q+#D",
6316 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6320 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6321 Secondary vtables are merged with primary vtables; this function
6322 will return the VAR_DECL for the primary vtable. */
6325 get_vtbl_decl_for_binfo (tree binfo)
6329 decl = BINFO_VTABLE (binfo);
6330 if (decl && TREE_CODE (decl) == PLUS_EXPR)
6332 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6333 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6336 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6341 /* Returns the binfo for the primary base of BINFO. If the resulting
6342 BINFO is a virtual base, and it is inherited elsewhere in the
6343 hierarchy, then the returned binfo might not be the primary base of
6344 BINFO in the complete object. Check BINFO_PRIMARY_P or
6345 BINFO_LOST_PRIMARY_P to be sure. */
6348 get_primary_binfo (tree binfo)
6352 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6356 return copied_binfo (primary_base, binfo);
6359 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6362 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6365 fprintf (stream, "%*s", indent, "");
6369 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6370 INDENT should be zero when called from the top level; it is
6371 incremented recursively. IGO indicates the next expected BINFO in
6372 inheritance graph ordering. */
6375 dump_class_hierarchy_r (FILE *stream,
6385 indented = maybe_indent_hierarchy (stream, indent, 0);
6386 fprintf (stream, "%s (0x%lx) ",
6387 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6388 (unsigned long) binfo);
6391 fprintf (stream, "alternative-path\n");
6394 igo = TREE_CHAIN (binfo);
6396 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6397 tree_low_cst (BINFO_OFFSET (binfo), 0));
6398 if (is_empty_class (BINFO_TYPE (binfo)))
6399 fprintf (stream, " empty");
6400 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6401 fprintf (stream, " nearly-empty");
6402 if (BINFO_VIRTUAL_P (binfo))
6403 fprintf (stream, " virtual");
6404 fprintf (stream, "\n");
6407 if (BINFO_PRIMARY_P (binfo))
6409 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6410 fprintf (stream, " primary-for %s (0x%lx)",
6411 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6412 TFF_PLAIN_IDENTIFIER),
6413 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6415 if (BINFO_LOST_PRIMARY_P (binfo))
6417 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6418 fprintf (stream, " lost-primary");
6421 fprintf (stream, "\n");
6423 if (!(flags & TDF_SLIM))
6427 if (BINFO_SUBVTT_INDEX (binfo))
6429 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6430 fprintf (stream, " subvttidx=%s",
6431 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6432 TFF_PLAIN_IDENTIFIER));
6434 if (BINFO_VPTR_INDEX (binfo))
6436 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6437 fprintf (stream, " vptridx=%s",
6438 expr_as_string (BINFO_VPTR_INDEX (binfo),
6439 TFF_PLAIN_IDENTIFIER));
6441 if (BINFO_VPTR_FIELD (binfo))
6443 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6444 fprintf (stream, " vbaseoffset=%s",
6445 expr_as_string (BINFO_VPTR_FIELD (binfo),
6446 TFF_PLAIN_IDENTIFIER));
6448 if (BINFO_VTABLE (binfo))
6450 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6451 fprintf (stream, " vptr=%s",
6452 expr_as_string (BINFO_VTABLE (binfo),
6453 TFF_PLAIN_IDENTIFIER));
6457 fprintf (stream, "\n");
6460 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6461 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6466 /* Dump the BINFO hierarchy for T. */
6469 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6471 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6472 fprintf (stream, " size=%lu align=%lu\n",
6473 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6474 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6475 fprintf (stream, " base size=%lu base align=%lu\n",
6476 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6478 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6480 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6481 fprintf (stream, "\n");
6484 /* Debug interface to hierarchy dumping. */
6487 debug_class (tree t)
6489 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6493 dump_class_hierarchy (tree t)
6496 FILE *stream = dump_begin (TDI_class, &flags);
6500 dump_class_hierarchy_1 (stream, flags, t);
6501 dump_end (TDI_class, stream);
6506 dump_array (FILE * stream, tree decl)
6509 unsigned HOST_WIDE_INT ix;
6511 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6513 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6515 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6516 fprintf (stream, " %s entries",
6517 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6518 TFF_PLAIN_IDENTIFIER));
6519 fprintf (stream, "\n");
6521 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
6523 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
6524 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
6528 dump_vtable (tree t, tree binfo, tree vtable)
6531 FILE *stream = dump_begin (TDI_class, &flags);
6536 if (!(flags & TDF_SLIM))
6538 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6540 fprintf (stream, "%s for %s",
6541 ctor_vtbl_p ? "Construction vtable" : "Vtable",
6542 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6545 if (!BINFO_VIRTUAL_P (binfo))
6546 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6547 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6549 fprintf (stream, "\n");
6550 dump_array (stream, vtable);
6551 fprintf (stream, "\n");
6554 dump_end (TDI_class, stream);
6558 dump_vtt (tree t, tree vtt)
6561 FILE *stream = dump_begin (TDI_class, &flags);
6566 if (!(flags & TDF_SLIM))
6568 fprintf (stream, "VTT for %s\n",
6569 type_as_string (t, TFF_PLAIN_IDENTIFIER));
6570 dump_array (stream, vtt);
6571 fprintf (stream, "\n");
6574 dump_end (TDI_class, stream);
6577 /* Dump a function or thunk and its thunkees. */
6580 dump_thunk (FILE *stream, int indent, tree thunk)
6582 static const char spaces[] = " ";
6583 tree name = DECL_NAME (thunk);
6586 fprintf (stream, "%.*s%p %s %s", indent, spaces,
6588 !DECL_THUNK_P (thunk) ? "function"
6589 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6590 name ? IDENTIFIER_POINTER (name) : "<unset>");
6591 if (DECL_THUNK_P (thunk))
6593 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6594 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6596 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6597 if (!virtual_adjust)
6599 else if (DECL_THIS_THUNK_P (thunk))
6600 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
6601 tree_low_cst (virtual_adjust, 0));
6603 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6604 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6605 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6606 if (THUNK_ALIAS (thunk))
6607 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6609 fprintf (stream, "\n");
6610 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6611 dump_thunk (stream, indent + 2, thunks);
6614 /* Dump the thunks for FN. */
6617 debug_thunks (tree fn)
6619 dump_thunk (stderr, 0, fn);
6622 /* Virtual function table initialization. */
6624 /* Create all the necessary vtables for T and its base classes. */
6627 finish_vtbls (tree t)
6632 /* We lay out the primary and secondary vtables in one contiguous
6633 vtable. The primary vtable is first, followed by the non-virtual
6634 secondary vtables in inheritance graph order. */
6635 list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6636 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6637 TYPE_BINFO (t), t, list);
6639 /* Then come the virtual bases, also in inheritance graph order. */
6640 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6642 if (!BINFO_VIRTUAL_P (vbase))
6644 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6647 if (BINFO_VTABLE (TYPE_BINFO (t)))
6648 initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
6651 /* Initialize the vtable for BINFO with the INITS. */
6654 initialize_vtable (tree binfo, tree inits)
6658 layout_vtable_decl (binfo, list_length (inits));
6659 decl = get_vtbl_decl_for_binfo (binfo);
6660 initialize_artificial_var (decl, inits);
6661 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
6664 /* Build the VTT (virtual table table) for T.
6665 A class requires a VTT if it has virtual bases.
6668 1 - primary virtual pointer for complete object T
6669 2 - secondary VTTs for each direct non-virtual base of T which requires a
6671 3 - secondary virtual pointers for each direct or indirect base of T which
6672 has virtual bases or is reachable via a virtual path from T.
6673 4 - secondary VTTs for each direct or indirect virtual base of T.
6675 Secondary VTTs look like complete object VTTs without part 4. */
6685 /* Build up the initializers for the VTT. */
6687 index = size_zero_node;
6688 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
6690 /* If we didn't need a VTT, we're done. */
6694 /* Figure out the type of the VTT. */
6695 type = build_index_type (size_int (list_length (inits) - 1));
6696 type = build_cplus_array_type (const_ptr_type_node, type);
6698 /* Now, build the VTT object itself. */
6699 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
6700 initialize_artificial_var (vtt, inits);
6701 /* Add the VTT to the vtables list. */
6702 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
6703 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
6708 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
6709 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
6710 and CHAIN the vtable pointer for this binfo after construction is
6711 complete. VALUE can also be another BINFO, in which case we recurse. */
6714 binfo_ctor_vtable (tree binfo)
6720 vt = BINFO_VTABLE (binfo);
6721 if (TREE_CODE (vt) == TREE_LIST)
6722 vt = TREE_VALUE (vt);
6723 if (TREE_CODE (vt) == TREE_BINFO)
6732 /* Data for secondary VTT initialization. */
6733 typedef struct secondary_vptr_vtt_init_data_s
6735 /* Is this the primary VTT? */
6738 /* Current index into the VTT. */
6741 /* TREE_LIST of initializers built up. */
6744 /* The type being constructed by this secondary VTT. */
6745 tree type_being_constructed;
6746 } secondary_vptr_vtt_init_data;
6748 /* Recursively build the VTT-initializer for BINFO (which is in the
6749 hierarchy dominated by T). INITS points to the end of the initializer
6750 list to date. INDEX is the VTT index where the next element will be
6751 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
6752 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
6753 for virtual bases of T. When it is not so, we build the constructor
6754 vtables for the BINFO-in-T variant. */
6757 build_vtt_inits (tree binfo, tree t, tree *inits, tree *index)
6762 tree secondary_vptrs;
6763 secondary_vptr_vtt_init_data data;
6764 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
6766 /* We only need VTTs for subobjects with virtual bases. */
6767 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
6770 /* We need to use a construction vtable if this is not the primary
6774 build_ctor_vtbl_group (binfo, t);
6776 /* Record the offset in the VTT where this sub-VTT can be found. */
6777 BINFO_SUBVTT_INDEX (binfo) = *index;
6780 /* Add the address of the primary vtable for the complete object. */
6781 init = binfo_ctor_vtable (binfo);
6782 *inits = build_tree_list (NULL_TREE, init);
6783 inits = &TREE_CHAIN (*inits);
6786 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6787 BINFO_VPTR_INDEX (binfo) = *index;
6789 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
6791 /* Recursively add the secondary VTTs for non-virtual bases. */
6792 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
6793 if (!BINFO_VIRTUAL_P (b))
6794 inits = build_vtt_inits (b, t, inits, index);
6796 /* Add secondary virtual pointers for all subobjects of BINFO with
6797 either virtual bases or reachable along a virtual path, except
6798 subobjects that are non-virtual primary bases. */
6799 data.top_level_p = top_level_p;
6800 data.index = *index;
6802 data.type_being_constructed = BINFO_TYPE (binfo);
6804 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
6806 *index = data.index;
6808 /* The secondary vptrs come back in reverse order. After we reverse
6809 them, and add the INITS, the last init will be the first element
6811 secondary_vptrs = data.inits;
6812 if (secondary_vptrs)
6814 *inits = nreverse (secondary_vptrs);
6815 inits = &TREE_CHAIN (secondary_vptrs);
6816 gcc_assert (*inits == NULL_TREE);
6820 /* Add the secondary VTTs for virtual bases in inheritance graph
6822 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
6824 if (!BINFO_VIRTUAL_P (b))
6827 inits = build_vtt_inits (b, t, inits, index);
6830 /* Remove the ctor vtables we created. */
6831 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
6836 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
6837 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
6840 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
6842 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
6844 /* We don't care about bases that don't have vtables. */
6845 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
6846 return dfs_skip_bases;
6848 /* We're only interested in proper subobjects of the type being
6850 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
6853 /* We're only interested in bases with virtual bases or reachable
6854 via a virtual path from the type being constructed. */
6855 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
6856 || binfo_via_virtual (binfo, data->type_being_constructed)))
6857 return dfs_skip_bases;
6859 /* We're not interested in non-virtual primary bases. */
6860 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
6863 /* Record the index where this secondary vptr can be found. */
6864 if (data->top_level_p)
6866 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6867 BINFO_VPTR_INDEX (binfo) = data->index;
6869 if (BINFO_VIRTUAL_P (binfo))
6871 /* It's a primary virtual base, and this is not a
6872 construction vtable. Find the base this is primary of in
6873 the inheritance graph, and use that base's vtable
6875 while (BINFO_PRIMARY_P (binfo))
6876 binfo = BINFO_INHERITANCE_CHAIN (binfo);
6880 /* Add the initializer for the secondary vptr itself. */
6881 data->inits = tree_cons (NULL_TREE, binfo_ctor_vtable (binfo), data->inits);
6883 /* Advance the vtt index. */
6884 data->index = size_binop (PLUS_EXPR, data->index,
6885 TYPE_SIZE_UNIT (ptr_type_node));
6890 /* Called from build_vtt_inits via dfs_walk. After building
6891 constructor vtables and generating the sub-vtt from them, we need
6892 to restore the BINFO_VTABLES that were scribbled on. DATA is the
6893 binfo of the base whose sub vtt was generated. */
6896 dfs_fixup_binfo_vtbls (tree binfo, void* data)
6898 tree vtable = BINFO_VTABLE (binfo);
6900 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
6901 /* If this class has no vtable, none of its bases do. */
6902 return dfs_skip_bases;
6905 /* This might be a primary base, so have no vtable in this
6909 /* If we scribbled the construction vtable vptr into BINFO, clear it
6911 if (TREE_CODE (vtable) == TREE_LIST
6912 && (TREE_PURPOSE (vtable) == (tree) data))
6913 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
6918 /* Build the construction vtable group for BINFO which is in the
6919 hierarchy dominated by T. */
6922 build_ctor_vtbl_group (tree binfo, tree t)
6931 /* See if we've already created this construction vtable group. */
6932 id = mangle_ctor_vtbl_for_type (t, binfo);
6933 if (IDENTIFIER_GLOBAL_VALUE (id))
6936 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
6937 /* Build a version of VTBL (with the wrong type) for use in
6938 constructing the addresses of secondary vtables in the
6939 construction vtable group. */
6940 vtbl = build_vtable (t, id, ptr_type_node);
6941 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
6942 list = build_tree_list (vtbl, NULL_TREE);
6943 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
6946 /* Add the vtables for each of our virtual bases using the vbase in T
6948 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
6950 vbase = TREE_CHAIN (vbase))
6954 if (!BINFO_VIRTUAL_P (vbase))
6956 b = copied_binfo (vbase, binfo);
6958 accumulate_vtbl_inits (b, vbase, binfo, t, list);
6960 inits = TREE_VALUE (list);
6962 /* Figure out the type of the construction vtable. */
6963 type = build_index_type (size_int (list_length (inits) - 1));
6964 type = build_cplus_array_type (vtable_entry_type, type);
6965 TREE_TYPE (vtbl) = type;
6967 /* Initialize the construction vtable. */
6968 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
6969 initialize_artificial_var (vtbl, inits);
6970 dump_vtable (t, binfo, vtbl);
6973 /* Add the vtbl initializers for BINFO (and its bases other than
6974 non-virtual primaries) to the list of INITS. BINFO is in the
6975 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
6976 the constructor the vtbl inits should be accumulated for. (If this
6977 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
6978 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
6979 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
6980 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
6981 but are not necessarily the same in terms of layout. */
6984 accumulate_vtbl_inits (tree binfo,
6992 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
6994 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
6996 /* If it doesn't have a vptr, we don't do anything. */
6997 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7000 /* If we're building a construction vtable, we're not interested in
7001 subobjects that don't require construction vtables. */
7003 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7004 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7007 /* Build the initializers for the BINFO-in-T vtable. */
7009 = chainon (TREE_VALUE (inits),
7010 dfs_accumulate_vtbl_inits (binfo, orig_binfo,
7011 rtti_binfo, t, inits));
7013 /* Walk the BINFO and its bases. We walk in preorder so that as we
7014 initialize each vtable we can figure out at what offset the
7015 secondary vtable lies from the primary vtable. We can't use
7016 dfs_walk here because we need to iterate through bases of BINFO
7017 and RTTI_BINFO simultaneously. */
7018 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7020 /* Skip virtual bases. */
7021 if (BINFO_VIRTUAL_P (base_binfo))
7023 accumulate_vtbl_inits (base_binfo,
7024 BINFO_BASE_BINFO (orig_binfo, i),
7030 /* Called from accumulate_vtbl_inits. Returns the initializers for
7031 the BINFO vtable. */
7034 dfs_accumulate_vtbl_inits (tree binfo,
7040 tree inits = NULL_TREE;
7041 tree vtbl = NULL_TREE;
7042 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7045 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7047 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7048 primary virtual base. If it is not the same primary in
7049 the hierarchy of T, we'll need to generate a ctor vtable
7050 for it, to place at its location in T. If it is the same
7051 primary, we still need a VTT entry for the vtable, but it
7052 should point to the ctor vtable for the base it is a
7053 primary for within the sub-hierarchy of RTTI_BINFO.
7055 There are three possible cases:
7057 1) We are in the same place.
7058 2) We are a primary base within a lost primary virtual base of
7060 3) We are primary to something not a base of RTTI_BINFO. */
7063 tree last = NULL_TREE;
7065 /* First, look through the bases we are primary to for RTTI_BINFO
7066 or a virtual base. */
7068 while (BINFO_PRIMARY_P (b))
7070 b = BINFO_INHERITANCE_CHAIN (b);
7072 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7075 /* If we run out of primary links, keep looking down our
7076 inheritance chain; we might be an indirect primary. */
7077 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7078 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7082 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7083 base B and it is a base of RTTI_BINFO, this is case 2. In
7084 either case, we share our vtable with LAST, i.e. the
7085 derived-most base within B of which we are a primary. */
7087 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7088 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7089 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7090 binfo_ctor_vtable after everything's been set up. */
7093 /* Otherwise, this is case 3 and we get our own. */
7095 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7103 /* Compute the initializer for this vtable. */
7104 inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7107 /* Figure out the position to which the VPTR should point. */
7108 vtbl = TREE_PURPOSE (l);
7109 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7110 index = size_binop (PLUS_EXPR,
7111 size_int (non_fn_entries),
7112 size_int (list_length (TREE_VALUE (l))));
7113 index = size_binop (MULT_EXPR,
7114 TYPE_SIZE_UNIT (vtable_entry_type),
7116 vtbl = build2 (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7120 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7121 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7122 straighten this out. */
7123 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7124 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7127 /* For an ordinary vtable, set BINFO_VTABLE. */
7128 BINFO_VTABLE (binfo) = vtbl;
7133 static GTY(()) tree abort_fndecl_addr;
7135 /* Construct the initializer for BINFO's virtual function table. BINFO
7136 is part of the hierarchy dominated by T. If we're building a
7137 construction vtable, the ORIG_BINFO is the binfo we should use to
7138 find the actual function pointers to put in the vtable - but they
7139 can be overridden on the path to most-derived in the graph that
7140 ORIG_BINFO belongs. Otherwise,
7141 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7142 BINFO that should be indicated by the RTTI information in the
7143 vtable; it will be a base class of T, rather than T itself, if we
7144 are building a construction vtable.
7146 The value returned is a TREE_LIST suitable for wrapping in a
7147 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7148 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7149 number of non-function entries in the vtable.
7151 It might seem that this function should never be called with a
7152 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7153 base is always subsumed by a derived class vtable. However, when
7154 we are building construction vtables, we do build vtables for
7155 primary bases; we need these while the primary base is being
7159 build_vtbl_initializer (tree binfo,
7163 int* non_fn_entries_p)
7170 VEC(tree,gc) *vbases;
7172 /* Initialize VID. */
7173 memset (&vid, 0, sizeof (vid));
7176 vid.rtti_binfo = rtti_binfo;
7177 vid.last_init = &vid.inits;
7178 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7179 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7180 vid.generate_vcall_entries = true;
7181 /* The first vbase or vcall offset is at index -3 in the vtable. */
7182 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7184 /* Add entries to the vtable for RTTI. */
7185 build_rtti_vtbl_entries (binfo, &vid);
7187 /* Create an array for keeping track of the functions we've
7188 processed. When we see multiple functions with the same
7189 signature, we share the vcall offsets. */
7190 vid.fns = VEC_alloc (tree, gc, 32);
7191 /* Add the vcall and vbase offset entries. */
7192 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7194 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7195 build_vbase_offset_vtbl_entries. */
7196 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7197 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7198 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7200 /* If the target requires padding between data entries, add that now. */
7201 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7205 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7210 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7211 add = tree_cons (NULL_TREE,
7212 build1 (NOP_EXPR, vtable_entry_type,
7219 if (non_fn_entries_p)
7220 *non_fn_entries_p = list_length (vid.inits);
7222 /* Go through all the ordinary virtual functions, building up
7224 vfun_inits = NULL_TREE;
7225 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7229 tree fn, fn_original;
7230 tree init = NULL_TREE;
7234 if (DECL_THUNK_P (fn))
7236 if (!DECL_NAME (fn))
7238 if (THUNK_ALIAS (fn))
7240 fn = THUNK_ALIAS (fn);
7243 fn_original = THUNK_TARGET (fn);
7246 /* If the only definition of this function signature along our
7247 primary base chain is from a lost primary, this vtable slot will
7248 never be used, so just zero it out. This is important to avoid
7249 requiring extra thunks which cannot be generated with the function.
7251 We first check this in update_vtable_entry_for_fn, so we handle
7252 restored primary bases properly; we also need to do it here so we
7253 zero out unused slots in ctor vtables, rather than filling themff
7254 with erroneous values (though harmless, apart from relocation
7256 for (b = binfo; ; b = get_primary_binfo (b))
7258 /* We found a defn before a lost primary; go ahead as normal. */
7259 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7262 /* The nearest definition is from a lost primary; clear the
7264 if (BINFO_LOST_PRIMARY_P (b))
7266 init = size_zero_node;
7273 /* Pull the offset for `this', and the function to call, out of
7275 delta = BV_DELTA (v);
7276 vcall_index = BV_VCALL_INDEX (v);
7278 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7279 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7281 /* You can't call an abstract virtual function; it's abstract.
7282 So, we replace these functions with __pure_virtual. */
7283 if (DECL_PURE_VIRTUAL_P (fn_original))
7286 if (abort_fndecl_addr == NULL)
7287 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7288 init = abort_fndecl_addr;
7292 if (!integer_zerop (delta) || vcall_index)
7294 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7295 if (!DECL_NAME (fn))
7298 /* Take the address of the function, considering it to be of an
7299 appropriate generic type. */
7300 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7304 /* And add it to the chain of initializers. */
7305 if (TARGET_VTABLE_USES_DESCRIPTORS)
7308 if (init == size_zero_node)
7309 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7310 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7312 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7314 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7315 TREE_OPERAND (init, 0),
7316 build_int_cst (NULL_TREE, i));
7317 TREE_CONSTANT (fdesc) = 1;
7318 TREE_INVARIANT (fdesc) = 1;
7320 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7324 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7327 /* The initializers for virtual functions were built up in reverse
7328 order; straighten them out now. */
7329 vfun_inits = nreverse (vfun_inits);
7331 /* The negative offset initializers are also in reverse order. */
7332 vid.inits = nreverse (vid.inits);
7334 /* Chain the two together. */
7335 return chainon (vid.inits, vfun_inits);
7338 /* Adds to vid->inits the initializers for the vbase and vcall
7339 offsets in BINFO, which is in the hierarchy dominated by T. */
7342 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7346 /* If this is a derived class, we must first create entries
7347 corresponding to the primary base class. */
7348 b = get_primary_binfo (binfo);
7350 build_vcall_and_vbase_vtbl_entries (b, vid);
7352 /* Add the vbase entries for this base. */
7353 build_vbase_offset_vtbl_entries (binfo, vid);
7354 /* Add the vcall entries for this base. */
7355 build_vcall_offset_vtbl_entries (binfo, vid);
7358 /* Returns the initializers for the vbase offset entries in the vtable
7359 for BINFO (which is part of the class hierarchy dominated by T), in
7360 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7361 where the next vbase offset will go. */
7364 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7368 tree non_primary_binfo;
7370 /* If there are no virtual baseclasses, then there is nothing to
7372 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7377 /* We might be a primary base class. Go up the inheritance hierarchy
7378 until we find the most derived class of which we are a primary base:
7379 it is the offset of that which we need to use. */
7380 non_primary_binfo = binfo;
7381 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7385 /* If we have reached a virtual base, then it must be a primary
7386 base (possibly multi-level) of vid->binfo, or we wouldn't
7387 have called build_vcall_and_vbase_vtbl_entries for it. But it
7388 might be a lost primary, so just skip down to vid->binfo. */
7389 if (BINFO_VIRTUAL_P (non_primary_binfo))
7391 non_primary_binfo = vid->binfo;
7395 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7396 if (get_primary_binfo (b) != non_primary_binfo)
7398 non_primary_binfo = b;
7401 /* Go through the virtual bases, adding the offsets. */
7402 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7404 vbase = TREE_CHAIN (vbase))
7409 if (!BINFO_VIRTUAL_P (vbase))
7412 /* Find the instance of this virtual base in the complete
7414 b = copied_binfo (vbase, binfo);
7416 /* If we've already got an offset for this virtual base, we
7417 don't need another one. */
7418 if (BINFO_VTABLE_PATH_MARKED (b))
7420 BINFO_VTABLE_PATH_MARKED (b) = 1;
7422 /* Figure out where we can find this vbase offset. */
7423 delta = size_binop (MULT_EXPR,
7426 TYPE_SIZE_UNIT (vtable_entry_type)));
7427 if (vid->primary_vtbl_p)
7428 BINFO_VPTR_FIELD (b) = delta;
7430 if (binfo != TYPE_BINFO (t))
7431 /* The vbase offset had better be the same. */
7432 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7434 /* The next vbase will come at a more negative offset. */
7435 vid->index = size_binop (MINUS_EXPR, vid->index,
7436 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7438 /* The initializer is the delta from BINFO to this virtual base.
7439 The vbase offsets go in reverse inheritance-graph order, and
7440 we are walking in inheritance graph order so these end up in
7442 delta = size_diffop (BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7445 = build_tree_list (NULL_TREE,
7446 fold_build1 (NOP_EXPR,
7449 vid->last_init = &TREE_CHAIN (*vid->last_init);
7453 /* Adds the initializers for the vcall offset entries in the vtable
7454 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7458 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7460 /* We only need these entries if this base is a virtual base. We
7461 compute the indices -- but do not add to the vtable -- when
7462 building the main vtable for a class. */
7463 if (binfo == TYPE_BINFO (vid->derived)
7464 || (BINFO_VIRTUAL_P (binfo)
7465 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7466 correspond to VID->DERIVED), we are building a primary
7467 construction virtual table. Since this is a primary
7468 virtual table, we do not need the vcall offsets for
7470 && binfo != vid->rtti_binfo))
7472 /* We need a vcall offset for each of the virtual functions in this
7473 vtable. For example:
7475 class A { virtual void f (); };
7476 class B1 : virtual public A { virtual void f (); };
7477 class B2 : virtual public A { virtual void f (); };
7478 class C: public B1, public B2 { virtual void f (); };
7480 A C object has a primary base of B1, which has a primary base of A. A
7481 C also has a secondary base of B2, which no longer has a primary base
7482 of A. So the B2-in-C construction vtable needs a secondary vtable for
7483 A, which will adjust the A* to a B2* to call f. We have no way of
7484 knowing what (or even whether) this offset will be when we define B2,
7485 so we store this "vcall offset" in the A sub-vtable and look it up in
7486 a "virtual thunk" for B2::f.
7488 We need entries for all the functions in our primary vtable and
7489 in our non-virtual bases' secondary vtables. */
7491 /* If we are just computing the vcall indices -- but do not need
7492 the actual entries -- not that. */
7493 if (!BINFO_VIRTUAL_P (binfo))
7494 vid->generate_vcall_entries = false;
7495 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7496 add_vcall_offset_vtbl_entries_r (binfo, vid);
7500 /* Build vcall offsets, starting with those for BINFO. */
7503 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7509 /* Don't walk into virtual bases -- except, of course, for the
7510 virtual base for which we are building vcall offsets. Any
7511 primary virtual base will have already had its offsets generated
7512 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7513 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7516 /* If BINFO has a primary base, process it first. */
7517 primary_binfo = get_primary_binfo (binfo);
7519 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7521 /* Add BINFO itself to the list. */
7522 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7524 /* Scan the non-primary bases of BINFO. */
7525 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7526 if (base_binfo != primary_binfo)
7527 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7530 /* Called from build_vcall_offset_vtbl_entries_r. */
7533 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7535 /* Make entries for the rest of the virtuals. */
7536 if (abi_version_at_least (2))
7540 /* The ABI requires that the methods be processed in declaration
7541 order. G++ 3.2 used the order in the vtable. */
7542 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7544 orig_fn = TREE_CHAIN (orig_fn))
7545 if (DECL_VINDEX (orig_fn))
7546 add_vcall_offset (orig_fn, binfo, vid);
7550 tree derived_virtuals;
7553 /* If BINFO is a primary base, the most derived class which has
7554 BINFO as a primary base; otherwise, just BINFO. */
7555 tree non_primary_binfo;
7557 /* We might be a primary base class. Go up the inheritance hierarchy
7558 until we find the most derived class of which we are a primary base:
7559 it is the BINFO_VIRTUALS there that we need to consider. */
7560 non_primary_binfo = binfo;
7561 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7565 /* If we have reached a virtual base, then it must be vid->vbase,
7566 because we ignore other virtual bases in
7567 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7568 base (possibly multi-level) of vid->binfo, or we wouldn't
7569 have called build_vcall_and_vbase_vtbl_entries for it. But it
7570 might be a lost primary, so just skip down to vid->binfo. */
7571 if (BINFO_VIRTUAL_P (non_primary_binfo))
7573 gcc_assert (non_primary_binfo == vid->vbase);
7574 non_primary_binfo = vid->binfo;
7578 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7579 if (get_primary_binfo (b) != non_primary_binfo)
7581 non_primary_binfo = b;
7584 if (vid->ctor_vtbl_p)
7585 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7586 where rtti_binfo is the most derived type. */
7588 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7590 for (base_virtuals = BINFO_VIRTUALS (binfo),
7591 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7592 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7594 base_virtuals = TREE_CHAIN (base_virtuals),
7595 derived_virtuals = TREE_CHAIN (derived_virtuals),
7596 orig_virtuals = TREE_CHAIN (orig_virtuals))
7600 /* Find the declaration that originally caused this function to
7601 be present in BINFO_TYPE (binfo). */
7602 orig_fn = BV_FN (orig_virtuals);
7604 /* When processing BINFO, we only want to generate vcall slots for
7605 function slots introduced in BINFO. So don't try to generate
7606 one if the function isn't even defined in BINFO. */
7607 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7610 add_vcall_offset (orig_fn, binfo, vid);
7615 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7618 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7624 /* If there is already an entry for a function with the same
7625 signature as FN, then we do not need a second vcall offset.
7626 Check the list of functions already present in the derived
7628 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7630 if (same_signature_p (derived_entry, orig_fn)
7631 /* We only use one vcall offset for virtual destructors,
7632 even though there are two virtual table entries. */
7633 || (DECL_DESTRUCTOR_P (derived_entry)
7634 && DECL_DESTRUCTOR_P (orig_fn)))
7638 /* If we are building these vcall offsets as part of building
7639 the vtable for the most derived class, remember the vcall
7641 if (vid->binfo == TYPE_BINFO (vid->derived))
7643 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
7644 CLASSTYPE_VCALL_INDICES (vid->derived),
7646 elt->purpose = orig_fn;
7647 elt->value = vid->index;
7650 /* The next vcall offset will be found at a more negative
7652 vid->index = size_binop (MINUS_EXPR, vid->index,
7653 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7655 /* Keep track of this function. */
7656 VEC_safe_push (tree, gc, vid->fns, orig_fn);
7658 if (vid->generate_vcall_entries)
7663 /* Find the overriding function. */
7664 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
7665 if (fn == error_mark_node)
7666 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
7670 base = TREE_VALUE (fn);
7672 /* The vbase we're working on is a primary base of
7673 vid->binfo. But it might be a lost primary, so its
7674 BINFO_OFFSET might be wrong, so we just use the
7675 BINFO_OFFSET from vid->binfo. */
7676 vcall_offset = size_diffop (BINFO_OFFSET (base),
7677 BINFO_OFFSET (vid->binfo));
7678 vcall_offset = fold_build1 (NOP_EXPR, vtable_entry_type,
7681 /* Add the initializer to the vtable. */
7682 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
7683 vid->last_init = &TREE_CHAIN (*vid->last_init);
7687 /* Return vtbl initializers for the RTTI entries corresponding to the
7688 BINFO's vtable. The RTTI entries should indicate the object given
7689 by VID->rtti_binfo. */
7692 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
7701 basetype = BINFO_TYPE (binfo);
7702 t = BINFO_TYPE (vid->rtti_binfo);
7704 /* To find the complete object, we will first convert to our most
7705 primary base, and then add the offset in the vtbl to that value. */
7707 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
7708 && !BINFO_LOST_PRIMARY_P (b))
7712 primary_base = get_primary_binfo (b);
7713 gcc_assert (BINFO_PRIMARY_P (primary_base)
7714 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
7717 offset = size_diffop (BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
7719 /* The second entry is the address of the typeinfo object. */
7721 decl = build_address (get_tinfo_decl (t));
7723 decl = integer_zero_node;
7725 /* Convert the declaration to a type that can be stored in the
7727 init = build_nop (vfunc_ptr_type_node, decl);
7728 *vid->last_init = build_tree_list (NULL_TREE, init);
7729 vid->last_init = &TREE_CHAIN (*vid->last_init);
7731 /* Add the offset-to-top entry. It comes earlier in the vtable than
7732 the typeinfo entry. Convert the offset to look like a
7733 function pointer, so that we can put it in the vtable. */
7734 init = build_nop (vfunc_ptr_type_node, offset);
7735 *vid->last_init = build_tree_list (NULL_TREE, init);
7736 vid->last_init = &TREE_CHAIN (*vid->last_init);
7739 /* Fold a OBJ_TYPE_REF expression to the address of a function.
7740 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
7743 cp_fold_obj_type_ref (tree ref, tree known_type)
7745 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
7746 HOST_WIDE_INT i = 0;
7747 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
7752 i += (TARGET_VTABLE_USES_DESCRIPTORS
7753 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
7759 #ifdef ENABLE_CHECKING
7760 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
7761 DECL_VINDEX (fndecl)));
7764 cgraph_node (fndecl)->local.vtable_method = true;
7766 return build_address (fndecl);
7769 #include "gt-cp-class.h"