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 Free Software Foundation, Inc.
4 Contributed by Michael Tiemann (tiemann@cygnus.com)
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to
20 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
24 /* High-level class interface. */
28 #include "coretypes.h"
39 #include "tree-dump.h"
41 /* The number of nested classes being processed. If we are not in the
42 scope of any class, this is zero. */
44 int current_class_depth;
46 /* In order to deal with nested classes, we keep a stack of classes.
47 The topmost entry is the innermost class, and is the entry at index
48 CURRENT_CLASS_DEPTH */
50 typedef struct class_stack_node {
51 /* The name of the class. */
54 /* The _TYPE node for the class. */
57 /* The access specifier pending for new declarations in the scope of
61 /* If were defining TYPE, the names used in this class. */
62 splay_tree names_used;
64 /* Nonzero if this class is no longer open, because of a call to
67 }* class_stack_node_t;
69 typedef struct vtbl_init_data_s
71 /* The base for which we're building initializers. */
73 /* The type of the most-derived type. */
75 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
76 unless ctor_vtbl_p is true. */
78 /* The negative-index vtable initializers built up so far. These
79 are in order from least negative index to most negative index. */
81 /* The last (i.e., most negative) entry in INITS. */
83 /* The binfo for the virtual base for which we're building
84 vcall offset initializers. */
86 /* The functions in vbase for which we have already provided vcall
89 /* The vtable index of the next vcall or vbase offset. */
91 /* Nonzero if we are building the initializer for the primary
94 /* Nonzero if we are building the initializer for a construction
97 /* True when adding vcall offset entries to the vtable. False when
98 merely computing the indices. */
99 bool generate_vcall_entries;
102 /* The type of a function passed to walk_subobject_offsets. */
103 typedef int (*subobject_offset_fn) (tree, tree, splay_tree);
105 /* The stack itself. This is a dynamically resized array. The
106 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
107 static int current_class_stack_size;
108 static class_stack_node_t current_class_stack;
110 /* The size of the largest empty class seen in this translation unit. */
111 static GTY (()) tree sizeof_biggest_empty_class;
113 /* An array of all local classes present in this translation unit, in
114 declaration order. */
115 VEC(tree,gc) *local_classes;
117 static tree get_vfield_name (tree);
118 static void finish_struct_anon (tree);
119 static tree get_vtable_name (tree);
120 static tree get_basefndecls (tree, tree);
121 static int build_primary_vtable (tree, tree);
122 static int build_secondary_vtable (tree);
123 static void finish_vtbls (tree);
124 static void modify_vtable_entry (tree, tree, tree, tree, tree *);
125 static void finish_struct_bits (tree);
126 static int alter_access (tree, tree, tree);
127 static void handle_using_decl (tree, tree);
128 static tree dfs_modify_vtables (tree, void *);
129 static tree modify_all_vtables (tree, tree);
130 static void determine_primary_bases (tree);
131 static void finish_struct_methods (tree);
132 static void maybe_warn_about_overly_private_class (tree);
133 static int method_name_cmp (const void *, const void *);
134 static int resort_method_name_cmp (const void *, const void *);
135 static void add_implicitly_declared_members (tree, int, int);
136 static tree fixed_type_or_null (tree, int *, int *);
137 static tree build_simple_base_path (tree expr, tree binfo);
138 static tree build_vtbl_ref_1 (tree, tree);
139 static tree build_vtbl_initializer (tree, tree, tree, tree, int *);
140 static int count_fields (tree);
141 static int add_fields_to_record_type (tree, struct sorted_fields_type*, int);
142 static void check_bitfield_decl (tree);
143 static void check_field_decl (tree, tree, int *, int *, int *);
144 static void check_field_decls (tree, tree *, int *, int *);
145 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
146 static void build_base_fields (record_layout_info, splay_tree, tree *);
147 static void check_methods (tree);
148 static void remove_zero_width_bit_fields (tree);
149 static void check_bases (tree, int *, int *);
150 static void check_bases_and_members (tree);
151 static tree create_vtable_ptr (tree, tree *);
152 static void include_empty_classes (record_layout_info);
153 static void layout_class_type (tree, tree *);
154 static void fixup_pending_inline (tree);
155 static void fixup_inline_methods (tree);
156 static void propagate_binfo_offsets (tree, tree);
157 static void layout_virtual_bases (record_layout_info, splay_tree);
158 static void build_vbase_offset_vtbl_entries (tree, vtbl_init_data *);
159 static void add_vcall_offset_vtbl_entries_r (tree, vtbl_init_data *);
160 static void add_vcall_offset_vtbl_entries_1 (tree, vtbl_init_data *);
161 static void build_vcall_offset_vtbl_entries (tree, vtbl_init_data *);
162 static void add_vcall_offset (tree, tree, vtbl_init_data *);
163 static void layout_vtable_decl (tree, int);
164 static tree dfs_find_final_overrider_pre (tree, void *);
165 static tree dfs_find_final_overrider_post (tree, void *);
166 static tree find_final_overrider (tree, tree, tree);
167 static int make_new_vtable (tree, tree);
168 static tree get_primary_binfo (tree);
169 static int maybe_indent_hierarchy (FILE *, int, int);
170 static tree dump_class_hierarchy_r (FILE *, int, tree, tree, int);
171 static void dump_class_hierarchy (tree);
172 static void dump_class_hierarchy_1 (FILE *, int, tree);
173 static void dump_array (FILE *, tree);
174 static void dump_vtable (tree, tree, tree);
175 static void dump_vtt (tree, tree);
176 static void dump_thunk (FILE *, int, tree);
177 static tree build_vtable (tree, tree, tree);
178 static void initialize_vtable (tree, tree);
179 static void layout_nonempty_base_or_field (record_layout_info,
180 tree, tree, splay_tree);
181 static tree end_of_class (tree, int);
182 static bool layout_empty_base (tree, tree, splay_tree);
183 static void accumulate_vtbl_inits (tree, tree, tree, tree, tree);
184 static tree dfs_accumulate_vtbl_inits (tree, tree, tree, tree,
186 static void build_rtti_vtbl_entries (tree, vtbl_init_data *);
187 static void build_vcall_and_vbase_vtbl_entries (tree, vtbl_init_data *);
188 static void clone_constructors_and_destructors (tree);
189 static tree build_clone (tree, tree);
190 static void update_vtable_entry_for_fn (tree, tree, tree, tree *, unsigned);
191 static void build_ctor_vtbl_group (tree, tree);
192 static void build_vtt (tree);
193 static tree binfo_ctor_vtable (tree);
194 static tree *build_vtt_inits (tree, tree, tree *, tree *);
195 static tree dfs_build_secondary_vptr_vtt_inits (tree, void *);
196 static tree dfs_fixup_binfo_vtbls (tree, void *);
197 static int record_subobject_offset (tree, tree, splay_tree);
198 static int check_subobject_offset (tree, tree, splay_tree);
199 static int walk_subobject_offsets (tree, subobject_offset_fn,
200 tree, splay_tree, tree, int);
201 static void record_subobject_offsets (tree, tree, splay_tree, bool);
202 static int layout_conflict_p (tree, tree, splay_tree, int);
203 static int splay_tree_compare_integer_csts (splay_tree_key k1,
205 static void warn_about_ambiguous_bases (tree);
206 static bool type_requires_array_cookie (tree);
207 static bool contains_empty_class_p (tree);
208 static bool base_derived_from (tree, tree);
209 static int empty_base_at_nonzero_offset_p (tree, tree, splay_tree);
210 static tree end_of_base (tree);
211 static tree get_vcall_index (tree, tree);
213 /* Variables shared between class.c and call.c. */
215 #ifdef GATHER_STATISTICS
217 int n_vtable_entries = 0;
218 int n_vtable_searches = 0;
219 int n_vtable_elems = 0;
220 int n_convert_harshness = 0;
221 int n_compute_conversion_costs = 0;
222 int n_inner_fields_searched = 0;
225 /* Convert to or from a base subobject. EXPR is an expression of type
226 `A' or `A*', an expression of type `B' or `B*' is returned. To
227 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
228 the B base instance within A. To convert base A to derived B, CODE
229 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
230 In this latter case, A must not be a morally virtual base of B.
231 NONNULL is true if EXPR is known to be non-NULL (this is only
232 needed when EXPR is of pointer type). CV qualifiers are preserved
236 build_base_path (enum tree_code code,
241 tree v_binfo = NULL_TREE;
242 tree d_binfo = NULL_TREE;
246 tree null_test = NULL;
247 tree ptr_target_type;
249 int want_pointer = TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE;
250 bool has_empty = false;
253 if (expr == error_mark_node || binfo == error_mark_node || !binfo)
254 return error_mark_node;
256 for (probe = binfo; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
259 if (is_empty_class (BINFO_TYPE (probe)))
261 if (!v_binfo && BINFO_VIRTUAL_P (probe))
265 probe = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
267 probe = TYPE_MAIN_VARIANT (TREE_TYPE (probe));
269 gcc_assert ((code == MINUS_EXPR
270 && SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), probe))
271 || (code == PLUS_EXPR
272 && SAME_BINFO_TYPE_P (BINFO_TYPE (d_binfo), probe)));
274 if (binfo == d_binfo)
278 if (code == MINUS_EXPR && v_binfo)
280 error ("cannot convert from base %qT to derived type %qT via virtual base %qT",
281 BINFO_TYPE (binfo), BINFO_TYPE (d_binfo), BINFO_TYPE (v_binfo));
282 return error_mark_node;
286 /* This must happen before the call to save_expr. */
287 expr = build_unary_op (ADDR_EXPR, expr, 0);
289 offset = BINFO_OFFSET (binfo);
290 fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull);
291 target_type = code == PLUS_EXPR ? BINFO_TYPE (binfo) : BINFO_TYPE (d_binfo);
293 /* Do we need to look in the vtable for the real offset? */
294 virtual_access = (v_binfo && fixed_type_p <= 0);
296 /* Do we need to check for a null pointer? */
297 if (want_pointer && !nonnull)
299 /* If we know the conversion will not actually change the value
300 of EXPR, then we can avoid testing the expression for NULL.
301 We have to avoid generating a COMPONENT_REF for a base class
302 field, because other parts of the compiler know that such
303 expressions are always non-NULL. */
304 if (!virtual_access && integer_zerop (offset))
307 /* TARGET_TYPE has been extracted from BINFO, and, is
308 therefore always cv-unqualified. Extract the
309 cv-qualifiers from EXPR so that the expression returned
310 matches the input. */
311 class_type = TREE_TYPE (TREE_TYPE (expr));
313 = cp_build_qualified_type (target_type,
314 cp_type_quals (class_type));
315 return build_nop (build_pointer_type (target_type), expr);
317 null_test = error_mark_node;
320 /* Protect against multiple evaluation if necessary. */
321 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
322 expr = save_expr (expr);
324 /* Now that we've saved expr, build the real null test. */
327 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
328 null_test = fold_build2 (NE_EXPR, boolean_type_node,
332 /* If this is a simple base reference, express it as a COMPONENT_REF. */
333 if (code == PLUS_EXPR && !virtual_access
334 /* We don't build base fields for empty bases, and they aren't very
335 interesting to the optimizers anyway. */
338 expr = build_indirect_ref (expr, NULL);
339 expr = build_simple_base_path (expr, binfo);
341 expr = build_address (expr);
342 target_type = TREE_TYPE (expr);
348 /* Going via virtual base V_BINFO. We need the static offset
349 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
350 V_BINFO. That offset is an entry in D_BINFO's vtable. */
353 if (fixed_type_p < 0 && in_base_initializer)
355 /* In a base member initializer, we cannot rely on the
356 vtable being set up. We have to indirect via the
360 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
361 t = build_pointer_type (t);
362 v_offset = convert (t, current_vtt_parm);
363 v_offset = build_indirect_ref (v_offset, NULL);
366 v_offset = build_vfield_ref (build_indirect_ref (expr, NULL),
367 TREE_TYPE (TREE_TYPE (expr)));
369 v_offset = build2 (PLUS_EXPR, TREE_TYPE (v_offset),
370 v_offset, BINFO_VPTR_FIELD (v_binfo));
371 v_offset = build1 (NOP_EXPR,
372 build_pointer_type (ptrdiff_type_node),
374 v_offset = build_indirect_ref (v_offset, NULL);
375 TREE_CONSTANT (v_offset) = 1;
376 TREE_INVARIANT (v_offset) = 1;
378 offset = convert_to_integer (ptrdiff_type_node,
380 BINFO_OFFSET (v_binfo)));
382 if (!integer_zerop (offset))
383 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
385 if (fixed_type_p < 0)
386 /* Negative fixed_type_p means this is a constructor or destructor;
387 virtual base layout is fixed in in-charge [cd]tors, but not in
389 offset = build3 (COND_EXPR, ptrdiff_type_node,
390 build2 (EQ_EXPR, boolean_type_node,
391 current_in_charge_parm, integer_zero_node),
393 convert_to_integer (ptrdiff_type_node,
394 BINFO_OFFSET (binfo)));
399 target_type = cp_build_qualified_type
400 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
401 ptr_target_type = build_pointer_type (target_type);
403 target_type = ptr_target_type;
405 expr = build1 (NOP_EXPR, ptr_target_type, expr);
407 if (!integer_zerop (offset))
408 expr = build2 (code, ptr_target_type, expr, offset);
413 expr = build_indirect_ref (expr, NULL);
417 expr = fold_build3 (COND_EXPR, target_type, null_test, expr,
418 fold_build1 (NOP_EXPR, target_type,
424 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
425 Perform a derived-to-base conversion by recursively building up a
426 sequence of COMPONENT_REFs to the appropriate base fields. */
429 build_simple_base_path (tree expr, tree binfo)
431 tree type = BINFO_TYPE (binfo);
432 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
435 if (d_binfo == NULL_TREE)
439 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
441 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
442 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
443 an lvalue in the frontend; only _DECLs and _REFs are lvalues
445 temp = unary_complex_lvalue (ADDR_EXPR, expr);
447 expr = build_indirect_ref (temp, NULL);
453 expr = build_simple_base_path (expr, d_binfo);
455 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
456 field; field = TREE_CHAIN (field))
457 /* Is this the base field created by build_base_field? */
458 if (TREE_CODE (field) == FIELD_DECL
459 && DECL_FIELD_IS_BASE (field)
460 && TREE_TYPE (field) == type)
462 /* We don't use build_class_member_access_expr here, as that
463 has unnecessary checks, and more importantly results in
464 recursive calls to dfs_walk_once. */
465 int type_quals = cp_type_quals (TREE_TYPE (expr));
467 expr = build3 (COMPONENT_REF,
468 cp_build_qualified_type (type, type_quals),
469 expr, field, NULL_TREE);
470 expr = fold_if_not_in_template (expr);
472 /* Mark the expression const or volatile, as appropriate.
473 Even though we've dealt with the type above, we still have
474 to mark the expression itself. */
475 if (type_quals & TYPE_QUAL_CONST)
476 TREE_READONLY (expr) = 1;
477 if (type_quals & TYPE_QUAL_VOLATILE)
478 TREE_THIS_VOLATILE (expr) = 1;
483 /* Didn't find the base field?!? */
487 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
488 type is a class type or a pointer to a class type. In the former
489 case, TYPE is also a class type; in the latter it is another
490 pointer type. If CHECK_ACCESS is true, an error message is emitted
491 if TYPE is inaccessible. If OBJECT has pointer type, the value is
492 assumed to be non-NULL. */
495 convert_to_base (tree object, tree type, bool check_access, bool nonnull)
500 if (TYPE_PTR_P (TREE_TYPE (object)))
502 object_type = TREE_TYPE (TREE_TYPE (object));
503 type = TREE_TYPE (type);
506 object_type = TREE_TYPE (object);
508 binfo = lookup_base (object_type, type,
509 check_access ? ba_check : ba_unique,
511 if (!binfo || binfo == error_mark_node)
512 return error_mark_node;
514 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
517 /* EXPR is an expression with unqualified class type. BASE is a base
518 binfo of that class type. Returns EXPR, converted to the BASE
519 type. This function assumes that EXPR is the most derived class;
520 therefore virtual bases can be found at their static offsets. */
523 convert_to_base_statically (tree expr, tree base)
527 expr_type = TREE_TYPE (expr);
528 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
532 pointer_type = build_pointer_type (expr_type);
533 expr = build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1);
534 if (!integer_zerop (BINFO_OFFSET (base)))
535 expr = build2 (PLUS_EXPR, pointer_type, expr,
536 build_nop (pointer_type, BINFO_OFFSET (base)));
537 expr = build_nop (build_pointer_type (BINFO_TYPE (base)), expr);
538 expr = build1 (INDIRECT_REF, BINFO_TYPE (base), expr);
546 build_vfield_ref (tree datum, tree type)
548 tree vfield, vcontext;
550 if (datum == error_mark_node)
551 return error_mark_node;
553 /* First, convert to the requested type. */
554 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
555 datum = convert_to_base (datum, type, /*check_access=*/false,
558 /* Second, the requested type may not be the owner of its own vptr.
559 If not, convert to the base class that owns it. We cannot use
560 convert_to_base here, because VCONTEXT may appear more than once
561 in the inheritance hierarchy of TYPE, and thus direct conversion
562 between the types may be ambiguous. Following the path back up
563 one step at a time via primary bases avoids the problem. */
564 vfield = TYPE_VFIELD (type);
565 vcontext = DECL_CONTEXT (vfield);
566 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
568 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
569 type = TREE_TYPE (datum);
572 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
575 /* Given an object INSTANCE, return an expression which yields the
576 vtable element corresponding to INDEX. There are many special
577 cases for INSTANCE which we take care of here, mainly to avoid
578 creating extra tree nodes when we don't have to. */
581 build_vtbl_ref_1 (tree instance, tree idx)
584 tree vtbl = NULL_TREE;
586 /* Try to figure out what a reference refers to, and
587 access its virtual function table directly. */
590 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
592 tree basetype = non_reference (TREE_TYPE (instance));
594 if (fixed_type && !cdtorp)
596 tree binfo = lookup_base (fixed_type, basetype,
597 ba_unique | ba_quiet, NULL);
599 vtbl = unshare_expr (BINFO_VTABLE (binfo));
603 vtbl = build_vfield_ref (instance, basetype);
605 assemble_external (vtbl);
607 aref = build_array_ref (vtbl, idx);
608 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
609 TREE_INVARIANT (aref) = TREE_CONSTANT (aref);
615 build_vtbl_ref (tree instance, tree idx)
617 tree aref = build_vtbl_ref_1 (instance, idx);
622 /* Given a stable object pointer INSTANCE_PTR, return an expression which
623 yields a function pointer corresponding to vtable element INDEX. */
626 build_vfn_ref (tree instance_ptr, tree idx)
630 aref = build_vtbl_ref_1 (build_indirect_ref (instance_ptr, 0), idx);
632 /* When using function descriptors, the address of the
633 vtable entry is treated as a function pointer. */
634 if (TARGET_VTABLE_USES_DESCRIPTORS)
635 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
636 build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1));
638 /* Remember this as a method reference, for later devirtualization. */
639 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
644 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
645 for the given TYPE. */
648 get_vtable_name (tree type)
650 return mangle_vtbl_for_type (type);
653 /* DECL is an entity associated with TYPE, like a virtual table or an
654 implicitly generated constructor. Determine whether or not DECL
655 should have external or internal linkage at the object file
656 level. This routine does not deal with COMDAT linkage and other
657 similar complexities; it simply sets TREE_PUBLIC if it possible for
658 entities in other translation units to contain copies of DECL, in
662 set_linkage_according_to_type (tree type, tree decl)
664 /* If TYPE involves a local class in a function with internal
665 linkage, then DECL should have internal linkage too. Other local
666 classes have no linkage -- but if their containing functions
667 have external linkage, it makes sense for DECL to have external
668 linkage too. That will allow template definitions to be merged,
670 if (no_linkage_check (type, /*relaxed_p=*/true))
672 TREE_PUBLIC (decl) = 0;
673 DECL_INTERFACE_KNOWN (decl) = 1;
676 TREE_PUBLIC (decl) = 1;
679 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
680 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
681 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
684 build_vtable (tree class_type, tree name, tree vtable_type)
688 decl = build_lang_decl (VAR_DECL, name, vtable_type);
689 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
690 now to avoid confusion in mangle_decl. */
691 SET_DECL_ASSEMBLER_NAME (decl, name);
692 DECL_CONTEXT (decl) = class_type;
693 DECL_ARTIFICIAL (decl) = 1;
694 TREE_STATIC (decl) = 1;
695 TREE_READONLY (decl) = 1;
696 DECL_VIRTUAL_P (decl) = 1;
697 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
698 DECL_VTABLE_OR_VTT_P (decl) = 1;
699 /* At one time the vtable info was grabbed 2 words at a time. This
700 fails on sparc unless you have 8-byte alignment. (tiemann) */
701 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
703 set_linkage_according_to_type (class_type, decl);
704 /* The vtable has not been defined -- yet. */
705 DECL_EXTERNAL (decl) = 1;
706 DECL_NOT_REALLY_EXTERN (decl) = 1;
708 /* Mark the VAR_DECL node representing the vtable itself as a
709 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
710 is rather important that such things be ignored because any
711 effort to actually generate DWARF for them will run into
712 trouble when/if we encounter code like:
715 struct S { virtual void member (); };
717 because the artificial declaration of the vtable itself (as
718 manufactured by the g++ front end) will say that the vtable is
719 a static member of `S' but only *after* the debug output for
720 the definition of `S' has already been output. This causes
721 grief because the DWARF entry for the definition of the vtable
722 will try to refer back to an earlier *declaration* of the
723 vtable as a static member of `S' and there won't be one. We
724 might be able to arrange to have the "vtable static member"
725 attached to the member list for `S' before the debug info for
726 `S' get written (which would solve the problem) but that would
727 require more intrusive changes to the g++ front end. */
728 DECL_IGNORED_P (decl) = 1;
733 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
734 or even complete. If this does not exist, create it. If COMPLETE is
735 nonzero, then complete the definition of it -- that will render it
736 impossible to actually build the vtable, but is useful to get at those
737 which are known to exist in the runtime. */
740 get_vtable_decl (tree type, int complete)
744 if (CLASSTYPE_VTABLES (type))
745 return CLASSTYPE_VTABLES (type);
747 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
748 CLASSTYPE_VTABLES (type) = decl;
752 DECL_EXTERNAL (decl) = 1;
753 finish_decl (decl, NULL_TREE, NULL_TREE);
759 /* Build the primary virtual function table for TYPE. If BINFO is
760 non-NULL, build the vtable starting with the initial approximation
761 that it is the same as the one which is the head of the association
762 list. Returns a nonzero value if a new vtable is actually
766 build_primary_vtable (tree binfo, tree type)
771 decl = get_vtable_decl (type, /*complete=*/0);
775 if (BINFO_NEW_VTABLE_MARKED (binfo))
776 /* We have already created a vtable for this base, so there's
777 no need to do it again. */
780 virtuals = copy_list (BINFO_VIRTUALS (binfo));
781 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
782 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
783 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
787 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
788 virtuals = NULL_TREE;
791 #ifdef GATHER_STATISTICS
793 n_vtable_elems += list_length (virtuals);
796 /* Initialize the association list for this type, based
797 on our first approximation. */
798 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
799 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
800 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
804 /* Give BINFO a new virtual function table which is initialized
805 with a skeleton-copy of its original initialization. The only
806 entry that changes is the `delta' entry, so we can really
807 share a lot of structure.
809 FOR_TYPE is the most derived type which caused this table to
812 Returns nonzero if we haven't met BINFO before.
814 The order in which vtables are built (by calling this function) for
815 an object must remain the same, otherwise a binary incompatibility
819 build_secondary_vtable (tree binfo)
821 if (BINFO_NEW_VTABLE_MARKED (binfo))
822 /* We already created a vtable for this base. There's no need to
826 /* Remember that we've created a vtable for this BINFO, so that we
827 don't try to do so again. */
828 SET_BINFO_NEW_VTABLE_MARKED (binfo);
830 /* Make fresh virtual list, so we can smash it later. */
831 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
833 /* Secondary vtables are laid out as part of the same structure as
834 the primary vtable. */
835 BINFO_VTABLE (binfo) = NULL_TREE;
839 /* Create a new vtable for BINFO which is the hierarchy dominated by
840 T. Return nonzero if we actually created a new vtable. */
843 make_new_vtable (tree t, tree binfo)
845 if (binfo == TYPE_BINFO (t))
846 /* In this case, it is *type*'s vtable we are modifying. We start
847 with the approximation that its vtable is that of the
848 immediate base class. */
849 return build_primary_vtable (binfo, t);
851 /* This is our very own copy of `basetype' to play with. Later,
852 we will fill in all the virtual functions that override the
853 virtual functions in these base classes which are not defined
854 by the current type. */
855 return build_secondary_vtable (binfo);
858 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
859 (which is in the hierarchy dominated by T) list FNDECL as its
860 BV_FN. DELTA is the required constant adjustment from the `this'
861 pointer where the vtable entry appears to the `this' required when
862 the function is actually called. */
865 modify_vtable_entry (tree t,
875 if (fndecl != BV_FN (v)
876 || !tree_int_cst_equal (delta, BV_DELTA (v)))
878 /* We need a new vtable for BINFO. */
879 if (make_new_vtable (t, binfo))
881 /* If we really did make a new vtable, we also made a copy
882 of the BINFO_VIRTUALS list. Now, we have to find the
883 corresponding entry in that list. */
884 *virtuals = BINFO_VIRTUALS (binfo);
885 while (BV_FN (*virtuals) != BV_FN (v))
886 *virtuals = TREE_CHAIN (*virtuals);
890 BV_DELTA (v) = delta;
891 BV_VCALL_INDEX (v) = NULL_TREE;
897 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
898 the USING_DECL naming METHOD. Returns true if the method could be
899 added to the method vec. */
902 add_method (tree type, tree method, tree using_decl)
906 bool template_conv_p = false;
908 VEC(tree,gc) *method_vec;
910 bool insert_p = false;
913 if (method == error_mark_node)
916 complete_p = COMPLETE_TYPE_P (type);
917 conv_p = DECL_CONV_FN_P (method);
919 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
920 && DECL_TEMPLATE_CONV_FN_P (method));
922 method_vec = CLASSTYPE_METHOD_VEC (type);
925 /* Make a new method vector. We start with 8 entries. We must
926 allocate at least two (for constructors and destructors), and
927 we're going to end up with an assignment operator at some
929 method_vec = VEC_alloc (tree, gc, 8);
930 /* Create slots for constructors and destructors. */
931 VEC_quick_push (tree, method_vec, NULL_TREE);
932 VEC_quick_push (tree, method_vec, NULL_TREE);
933 CLASSTYPE_METHOD_VEC (type) = method_vec;
936 /* Maintain TYPE_HAS_CONSTRUCTOR, etc. */
937 grok_special_member_properties (method);
939 /* Constructors and destructors go in special slots. */
940 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
941 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
942 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
944 slot = CLASSTYPE_DESTRUCTOR_SLOT;
946 if (TYPE_FOR_JAVA (type))
948 if (!DECL_ARTIFICIAL (method))
949 error ("Java class %qT cannot have a destructor", type);
950 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
951 error ("Java class %qT cannot have an implicit non-trivial "
961 /* See if we already have an entry with this name. */
962 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
963 VEC_iterate (tree, method_vec, slot, m);
969 if (TREE_CODE (m) == TEMPLATE_DECL
970 && DECL_TEMPLATE_CONV_FN_P (m))
974 if (conv_p && !DECL_CONV_FN_P (m))
976 if (DECL_NAME (m) == DECL_NAME (method))
982 && !DECL_CONV_FN_P (m)
983 && DECL_NAME (m) > DECL_NAME (method))
987 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
989 if (processing_template_decl)
990 /* TYPE is a template class. Don't issue any errors now; wait
991 until instantiation time to complain. */
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. */
1078 /* A class should never have more than one destructor. */
1079 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1082 /* Add the new binding. */
1083 overload = build_overload (method, current_fns);
1086 TYPE_HAS_CONVERSION (type) = 1;
1087 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1088 push_class_level_binding (DECL_NAME (method), overload);
1094 /* We only expect to add few methods in the COMPLETE_P case, so
1095 just make room for one more method in that case. */
1097 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1099 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1101 CLASSTYPE_METHOD_VEC (type) = method_vec;
1102 if (slot == VEC_length (tree, method_vec))
1103 VEC_quick_push (tree, method_vec, overload);
1105 VEC_quick_insert (tree, method_vec, slot, overload);
1108 /* Replace the current slot. */
1109 VEC_replace (tree, method_vec, slot, overload);
1113 /* Subroutines of finish_struct. */
1115 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1116 legit, otherwise return 0. */
1119 alter_access (tree t, tree fdecl, tree access)
1123 if (!DECL_LANG_SPECIFIC (fdecl))
1124 retrofit_lang_decl (fdecl);
1126 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1128 elem = purpose_member (t, DECL_ACCESS (fdecl));
1131 if (TREE_VALUE (elem) != access)
1133 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1134 error ("conflicting access specifications for method"
1135 " %q+D, ignored", TREE_TYPE (fdecl));
1137 error ("conflicting access specifications for field %qE, ignored",
1142 /* They're changing the access to the same thing they changed
1143 it to before. That's OK. */
1149 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1150 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1156 /* Process the USING_DECL, which is a member of T. */
1159 handle_using_decl (tree using_decl, tree t)
1161 tree decl = USING_DECL_DECLS (using_decl);
1162 tree name = DECL_NAME (using_decl);
1164 = TREE_PRIVATE (using_decl) ? access_private_node
1165 : TREE_PROTECTED (using_decl) ? access_protected_node
1166 : access_public_node;
1167 tree flist = NULL_TREE;
1170 gcc_assert (!processing_template_decl && decl);
1172 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1175 if (is_overloaded_fn (old_value))
1176 old_value = OVL_CURRENT (old_value);
1178 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1181 old_value = NULL_TREE;
1184 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1186 if (is_overloaded_fn (decl))
1191 else if (is_overloaded_fn (old_value))
1194 /* It's OK to use functions from a base when there are functions with
1195 the same name already present in the current class. */;
1198 error ("%q+D invalid in %q#T", using_decl, t);
1199 error (" because of local method %q+#D with same name",
1200 OVL_CURRENT (old_value));
1204 else if (!DECL_ARTIFICIAL (old_value))
1206 error ("%q+D invalid in %q#T", using_decl, t);
1207 error (" because of local member %q+#D with same name", old_value);
1211 /* Make type T see field decl FDECL with access ACCESS. */
1213 for (; flist; flist = OVL_NEXT (flist))
1215 add_method (t, OVL_CURRENT (flist), using_decl);
1216 alter_access (t, OVL_CURRENT (flist), access);
1219 alter_access (t, decl, access);
1222 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1223 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1224 properties of the bases. */
1227 check_bases (tree t,
1228 int* cant_have_const_ctor_p,
1229 int* no_const_asn_ref_p)
1232 int seen_non_virtual_nearly_empty_base_p;
1236 seen_non_virtual_nearly_empty_base_p = 0;
1238 for (binfo = TYPE_BINFO (t), i = 0;
1239 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1241 tree basetype = TREE_TYPE (base_binfo);
1243 gcc_assert (COMPLETE_TYPE_P (basetype));
1245 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1246 here because the case of virtual functions but non-virtual
1247 dtor is handled in finish_struct_1. */
1248 if (!TYPE_POLYMORPHIC_P (basetype))
1249 warning (OPT_Weffc__,
1250 "base class %q#T has a non-virtual destructor", basetype);
1252 /* If the base class doesn't have copy constructors or
1253 assignment operators that take const references, then the
1254 derived class cannot have such a member automatically
1256 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1257 *cant_have_const_ctor_p = 1;
1258 if (TYPE_HAS_ASSIGN_REF (basetype)
1259 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1260 *no_const_asn_ref_p = 1;
1262 if (BINFO_VIRTUAL_P (base_binfo))
1263 /* A virtual base does not effect nearly emptiness. */
1265 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1267 if (seen_non_virtual_nearly_empty_base_p)
1268 /* And if there is more than one nearly empty base, then the
1269 derived class is not nearly empty either. */
1270 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1272 /* Remember we've seen one. */
1273 seen_non_virtual_nearly_empty_base_p = 1;
1275 else if (!is_empty_class (basetype))
1276 /* If the base class is not empty or nearly empty, then this
1277 class cannot be nearly empty. */
1278 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1280 /* A lot of properties from the bases also apply to the derived
1282 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1283 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1284 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1285 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1286 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1287 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1288 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1289 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1290 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (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 backend
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_THUNK_P (fn));
2120 /* Assume that we will produce a thunk that convert all the way to
2121 the final overrider, and not to an intermediate virtual base. */
2122 virtual_base = NULL_TREE;
2124 /* See if we can convert to an intermediate virtual base first, and then
2125 use the vcall offset located there to finish the conversion. */
2126 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2128 /* If we find the final overrider, then we can stop
2130 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2131 BINFO_TYPE (TREE_VALUE (overrider))))
2134 /* If we find a virtual base, and we haven't yet found the
2135 overrider, then there is a virtual base between the
2136 declaring base (first_defn) and the final overrider. */
2137 if (BINFO_VIRTUAL_P (b))
2144 if (overrider_fn != overrider_target && !virtual_base)
2146 /* The ABI specifies that a covariant thunk includes a mangling
2147 for a this pointer adjustment. This-adjusting thunks that
2148 override a function from a virtual base have a vcall
2149 adjustment. When the virtual base in question is a primary
2150 virtual base, we know the adjustments are zero, (and in the
2151 non-covariant case, we would not use the thunk).
2152 Unfortunately we didn't notice this could happen, when
2153 designing the ABI and so never mandated that such a covariant
2154 thunk should be emitted. Because we must use the ABI mandated
2155 name, we must continue searching from the binfo where we
2156 found the most recent definition of the function, towards the
2157 primary binfo which first introduced the function into the
2158 vtable. If that enters a virtual base, we must use a vcall
2159 this-adjusting thunk. Bleah! */
2160 tree probe = first_defn;
2162 while ((probe = get_primary_binfo (probe))
2163 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2164 if (BINFO_VIRTUAL_P (probe))
2165 virtual_base = probe;
2168 /* Even if we find a virtual base, the correct delta is
2169 between the overrider and the binfo we're building a vtable
2171 goto virtual_covariant;
2174 /* Compute the constant adjustment to the `this' pointer. The
2175 `this' pointer, when this function is called, will point at BINFO
2176 (or one of its primary bases, which are at the same offset). */
2178 /* The `this' pointer needs to be adjusted from the declaration to
2179 the nearest virtual base. */
2180 delta = size_diffop (convert (ssizetype, BINFO_OFFSET (virtual_base)),
2181 convert (ssizetype, BINFO_OFFSET (first_defn)));
2183 /* If the nearest definition is in a lost primary, we don't need an
2184 entry in our vtable. Except possibly in a constructor vtable,
2185 if we happen to get our primary back. In that case, the offset
2186 will be zero, as it will be a primary base. */
2187 delta = size_zero_node;
2189 /* The `this' pointer needs to be adjusted from pointing to
2190 BINFO to pointing at the base where the final overrider
2193 delta = size_diffop (convert (ssizetype,
2194 BINFO_OFFSET (TREE_VALUE (overrider))),
2195 convert (ssizetype, BINFO_OFFSET (binfo)));
2197 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2200 BV_VCALL_INDEX (*virtuals)
2201 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2203 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2206 /* Called from modify_all_vtables via dfs_walk. */
2209 dfs_modify_vtables (tree binfo, void* data)
2211 tree t = (tree) data;
2216 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2217 /* A base without a vtable needs no modification, and its bases
2218 are uninteresting. */
2219 return dfs_skip_bases;
2221 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2222 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2223 /* Don't do the primary vtable, if it's new. */
2226 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2227 /* There's no need to modify the vtable for a non-virtual primary
2228 base; we're not going to use that vtable anyhow. We do still
2229 need to do this for virtual primary bases, as they could become
2230 non-primary in a construction vtable. */
2233 make_new_vtable (t, binfo);
2235 /* Now, go through each of the virtual functions in the virtual
2236 function table for BINFO. Find the final overrider, and update
2237 the BINFO_VIRTUALS list appropriately. */
2238 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2239 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2241 ix++, virtuals = TREE_CHAIN (virtuals),
2242 old_virtuals = TREE_CHAIN (old_virtuals))
2243 update_vtable_entry_for_fn (t,
2245 BV_FN (old_virtuals),
2251 /* Update all of the primary and secondary vtables for T. Create new
2252 vtables as required, and initialize their RTTI information. Each
2253 of the functions in VIRTUALS is declared in T and may override a
2254 virtual function from a base class; find and modify the appropriate
2255 entries to point to the overriding functions. Returns a list, in
2256 declaration order, of the virtual functions that are declared in T,
2257 but do not appear in the primary base class vtable, and which
2258 should therefore be appended to the end of the vtable for T. */
2261 modify_all_vtables (tree t, tree virtuals)
2263 tree binfo = TYPE_BINFO (t);
2266 /* Update all of the vtables. */
2267 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2269 /* Add virtual functions not already in our primary vtable. These
2270 will be both those introduced by this class, and those overridden
2271 from secondary bases. It does not include virtuals merely
2272 inherited from secondary bases. */
2273 for (fnsp = &virtuals; *fnsp; )
2275 tree fn = TREE_VALUE (*fnsp);
2277 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2278 || DECL_VINDEX (fn) == error_mark_node)
2280 /* We don't need to adjust the `this' pointer when
2281 calling this function. */
2282 BV_DELTA (*fnsp) = integer_zero_node;
2283 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2285 /* This is a function not already in our vtable. Keep it. */
2286 fnsp = &TREE_CHAIN (*fnsp);
2289 /* We've already got an entry for this function. Skip it. */
2290 *fnsp = TREE_CHAIN (*fnsp);
2296 /* Get the base virtual function declarations in T that have the
2300 get_basefndecls (tree name, tree t)
2303 tree base_fndecls = NULL_TREE;
2304 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2307 /* Find virtual functions in T with the indicated NAME. */
2308 i = lookup_fnfields_1 (t, name);
2310 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2312 methods = OVL_NEXT (methods))
2314 tree method = OVL_CURRENT (methods);
2316 if (TREE_CODE (method) == FUNCTION_DECL
2317 && DECL_VINDEX (method))
2318 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2322 return base_fndecls;
2324 for (i = 0; i < n_baseclasses; i++)
2326 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2327 base_fndecls = chainon (get_basefndecls (name, basetype),
2331 return base_fndecls;
2334 /* If this declaration supersedes the declaration of
2335 a method declared virtual in the base class, then
2336 mark this field as being virtual as well. */
2339 check_for_override (tree decl, tree ctype)
2341 if (TREE_CODE (decl) == TEMPLATE_DECL)
2342 /* In [temp.mem] we have:
2344 A specialization of a member function template does not
2345 override a virtual function from a base class. */
2347 if ((DECL_DESTRUCTOR_P (decl)
2348 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2349 || DECL_CONV_FN_P (decl))
2350 && look_for_overrides (ctype, decl)
2351 && !DECL_STATIC_FUNCTION_P (decl))
2352 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2353 the error_mark_node so that we know it is an overriding
2355 DECL_VINDEX (decl) = decl;
2357 if (DECL_VIRTUAL_P (decl))
2359 if (!DECL_VINDEX (decl))
2360 DECL_VINDEX (decl) = error_mark_node;
2361 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2362 if (DECL_DLLIMPORT_P (decl))
2364 /* When we handled the dllimport attribute we may not have known
2365 that this function is virtual We can't use dllimport
2366 semantics for a virtual method because we need to initialize
2367 the vtable entry with a constant address. */
2368 DECL_DLLIMPORT_P (decl) = 0;
2369 DECL_ATTRIBUTES (decl)
2370 = remove_attribute ("dllimport", DECL_ATTRIBUTES (decl));
2375 /* Warn about hidden virtual functions that are not overridden in t.
2376 We know that constructors and destructors don't apply. */
2379 warn_hidden (tree t)
2381 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2385 /* We go through each separately named virtual function. */
2386 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2387 VEC_iterate (tree, method_vec, i, fns);
2398 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2399 have the same name. Figure out what name that is. */
2400 name = DECL_NAME (OVL_CURRENT (fns));
2401 /* There are no possibly hidden functions yet. */
2402 base_fndecls = NULL_TREE;
2403 /* Iterate through all of the base classes looking for possibly
2404 hidden functions. */
2405 for (binfo = TYPE_BINFO (t), j = 0;
2406 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2408 tree basetype = BINFO_TYPE (base_binfo);
2409 base_fndecls = chainon (get_basefndecls (name, basetype),
2413 /* If there are no functions to hide, continue. */
2417 /* Remove any overridden functions. */
2418 for (fn = fns; fn; fn = OVL_NEXT (fn))
2420 fndecl = OVL_CURRENT (fn);
2421 if (DECL_VINDEX (fndecl))
2423 tree *prev = &base_fndecls;
2426 /* If the method from the base class has the same
2427 signature as the method from the derived class, it
2428 has been overridden. */
2429 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2430 *prev = TREE_CHAIN (*prev);
2432 prev = &TREE_CHAIN (*prev);
2436 /* Now give a warning for all base functions without overriders,
2437 as they are hidden. */
2438 while (base_fndecls)
2440 /* Here we know it is a hider, and no overrider exists. */
2441 warning (0, "%q+D was hidden", TREE_VALUE (base_fndecls));
2442 warning (0, " by %q+D", fns);
2443 base_fndecls = TREE_CHAIN (base_fndecls);
2448 /* Check for things that are invalid. There are probably plenty of other
2449 things we should check for also. */
2452 finish_struct_anon (tree t)
2456 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2458 if (TREE_STATIC (field))
2460 if (TREE_CODE (field) != FIELD_DECL)
2463 if (DECL_NAME (field) == NULL_TREE
2464 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2466 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2467 for (; elt; elt = TREE_CHAIN (elt))
2469 /* We're generally only interested in entities the user
2470 declared, but we also find nested classes by noticing
2471 the TYPE_DECL that we create implicitly. You're
2472 allowed to put one anonymous union inside another,
2473 though, so we explicitly tolerate that. We use
2474 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2475 we also allow unnamed types used for defining fields. */
2476 if (DECL_ARTIFICIAL (elt)
2477 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2478 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2481 if (TREE_CODE (elt) != FIELD_DECL)
2483 pedwarn ("%q+#D invalid; an anonymous union can "
2484 "only have non-static data members", elt);
2488 if (TREE_PRIVATE (elt))
2489 pedwarn ("private member %q+#D in anonymous union", elt);
2490 else if (TREE_PROTECTED (elt))
2491 pedwarn ("protected member %q+#D in anonymous union", elt);
2493 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2494 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2500 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2501 will be used later during class template instantiation.
2502 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2503 a non-static member data (FIELD_DECL), a member function
2504 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2505 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2506 When FRIEND_P is nonzero, T is either a friend class
2507 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2508 (FUNCTION_DECL, TEMPLATE_DECL). */
2511 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2513 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2514 if (CLASSTYPE_TEMPLATE_INFO (type))
2515 CLASSTYPE_DECL_LIST (type)
2516 = tree_cons (friend_p ? NULL_TREE : type,
2517 t, CLASSTYPE_DECL_LIST (type));
2520 /* Create default constructors, assignment operators, and so forth for
2521 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2522 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2523 the class cannot have a default constructor, copy constructor
2524 taking a const reference argument, or an assignment operator taking
2525 a const reference, respectively. */
2528 add_implicitly_declared_members (tree t,
2529 int cant_have_const_cctor,
2530 int cant_have_const_assignment)
2533 if (!CLASSTYPE_DESTRUCTORS (t))
2535 /* In general, we create destructors lazily. */
2536 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2537 /* However, if the implicit destructor is non-trivial
2538 destructor, we sometimes have to create it at this point. */
2539 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2543 if (TYPE_FOR_JAVA (t))
2544 /* If this a Java class, any non-trivial destructor is
2545 invalid, even if compiler-generated. Therefore, if the
2546 destructor is non-trivial we create it now. */
2554 /* If the implicit destructor will be virtual, then we must
2555 generate it now because (unfortunately) we do not
2556 generate virtual tables lazily. */
2557 binfo = TYPE_BINFO (t);
2558 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2563 base_type = BINFO_TYPE (base_binfo);
2564 dtor = CLASSTYPE_DESTRUCTORS (base_type);
2565 if (dtor && DECL_VIRTUAL_P (dtor))
2573 /* If we can't get away with being lazy, generate the destructor
2576 lazily_declare_fn (sfk_destructor, t);
2580 /* Default constructor. */
2581 if (! TYPE_HAS_CONSTRUCTOR (t))
2583 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2584 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2587 /* Copy constructor. */
2588 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2590 TYPE_HAS_INIT_REF (t) = 1;
2591 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2592 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2593 TYPE_HAS_CONSTRUCTOR (t) = 1;
2596 /* If there is no assignment operator, one will be created if and
2597 when it is needed. For now, just record whether or not the type
2598 of the parameter to the assignment operator will be a const or
2599 non-const reference. */
2600 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2602 TYPE_HAS_ASSIGN_REF (t) = 1;
2603 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2604 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2608 /* Subroutine of finish_struct_1. Recursively count the number of fields
2609 in TYPE, including anonymous union members. */
2612 count_fields (tree fields)
2616 for (x = fields; x; x = TREE_CHAIN (x))
2618 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2619 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2626 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2627 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2630 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2633 for (x = fields; x; x = TREE_CHAIN (x))
2635 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2636 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2638 field_vec->elts[idx++] = x;
2643 /* FIELD is a bit-field. We are finishing the processing for its
2644 enclosing type. Issue any appropriate messages and set appropriate
2648 check_bitfield_decl (tree field)
2650 tree type = TREE_TYPE (field);
2653 /* Extract the declared width of the bitfield, which has been
2654 temporarily stashed in DECL_INITIAL. */
2655 w = DECL_INITIAL (field);
2656 gcc_assert (w != NULL_TREE);
2657 /* Remove the bit-field width indicator so that the rest of the
2658 compiler does not treat that value as an initializer. */
2659 DECL_INITIAL (field) = NULL_TREE;
2661 /* Detect invalid bit-field type. */
2662 if (!INTEGRAL_TYPE_P (type))
2664 error ("bit-field %q+#D with non-integral type", field);
2665 TREE_TYPE (field) = error_mark_node;
2666 w = error_mark_node;
2670 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2673 /* detect invalid field size. */
2674 w = integral_constant_value (w);
2676 if (TREE_CODE (w) != INTEGER_CST)
2678 error ("bit-field %q+D width not an integer constant", field);
2679 w = error_mark_node;
2681 else if (tree_int_cst_sgn (w) < 0)
2683 error ("negative width in bit-field %q+D", field);
2684 w = error_mark_node;
2686 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2688 error ("zero width for bit-field %q+D", field);
2689 w = error_mark_node;
2691 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2692 && TREE_CODE (type) != ENUMERAL_TYPE
2693 && TREE_CODE (type) != BOOLEAN_TYPE)
2694 warning (0, "width of %q+D exceeds its type", field);
2695 else if (TREE_CODE (type) == ENUMERAL_TYPE
2696 && (0 > compare_tree_int (w,
2697 min_precision (TYPE_MIN_VALUE (type),
2698 TYPE_UNSIGNED (type)))
2699 || 0 > compare_tree_int (w,
2701 (TYPE_MAX_VALUE (type),
2702 TYPE_UNSIGNED (type)))))
2703 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2706 if (w != error_mark_node)
2708 DECL_SIZE (field) = convert (bitsizetype, w);
2709 DECL_BIT_FIELD (field) = 1;
2713 /* Non-bit-fields are aligned for their type. */
2714 DECL_BIT_FIELD (field) = 0;
2715 CLEAR_DECL_C_BIT_FIELD (field);
2719 /* FIELD is a non bit-field. We are finishing the processing for its
2720 enclosing type T. Issue any appropriate messages and set appropriate
2724 check_field_decl (tree field,
2726 int* cant_have_const_ctor,
2727 int* no_const_asn_ref,
2728 int* any_default_members)
2730 tree type = strip_array_types (TREE_TYPE (field));
2732 /* An anonymous union cannot contain any fields which would change
2733 the settings of CANT_HAVE_CONST_CTOR and friends. */
2734 if (ANON_UNION_TYPE_P (type))
2736 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2737 structs. So, we recurse through their fields here. */
2738 else if (ANON_AGGR_TYPE_P (type))
2742 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2743 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2744 check_field_decl (fields, t, cant_have_const_ctor,
2745 no_const_asn_ref, any_default_members);
2747 /* Check members with class type for constructors, destructors,
2749 else if (CLASS_TYPE_P (type))
2751 /* Never let anything with uninheritable virtuals
2752 make it through without complaint. */
2753 abstract_virtuals_error (field, type);
2755 if (TREE_CODE (t) == UNION_TYPE)
2757 if (TYPE_NEEDS_CONSTRUCTING (type))
2758 error ("member %q+#D with constructor not allowed in union",
2760 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2761 error ("member %q+#D with destructor not allowed in union", field);
2762 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2763 error ("member %q+#D with copy assignment operator not allowed in union",
2768 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2769 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2770 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2771 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2772 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2775 if (!TYPE_HAS_CONST_INIT_REF (type))
2776 *cant_have_const_ctor = 1;
2778 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2779 *no_const_asn_ref = 1;
2781 if (DECL_INITIAL (field) != NULL_TREE)
2783 /* `build_class_init_list' does not recognize
2785 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2786 error ("multiple fields in union %qT initialized", t);
2787 *any_default_members = 1;
2791 /* Check the data members (both static and non-static), class-scoped
2792 typedefs, etc., appearing in the declaration of T. Issue
2793 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2794 declaration order) of access declarations; each TREE_VALUE in this
2795 list is a USING_DECL.
2797 In addition, set the following flags:
2800 The class is empty, i.e., contains no non-static data members.
2802 CANT_HAVE_CONST_CTOR_P
2803 This class cannot have an implicitly generated copy constructor
2804 taking a const reference.
2806 CANT_HAVE_CONST_ASN_REF
2807 This class cannot have an implicitly generated assignment
2808 operator taking a const reference.
2810 All of these flags should be initialized before calling this
2813 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2814 fields can be added by adding to this chain. */
2817 check_field_decls (tree t, tree *access_decls,
2818 int *cant_have_const_ctor_p,
2819 int *no_const_asn_ref_p)
2824 int any_default_members;
2827 /* Assume there are no access declarations. */
2828 *access_decls = NULL_TREE;
2829 /* Assume this class has no pointer members. */
2830 has_pointers = false;
2831 /* Assume none of the members of this class have default
2833 any_default_members = 0;
2835 for (field = &TYPE_FIELDS (t); *field; field = next)
2838 tree type = TREE_TYPE (x);
2840 next = &TREE_CHAIN (x);
2842 if (TREE_CODE (x) == USING_DECL)
2844 /* Prune the access declaration from the list of fields. */
2845 *field = TREE_CHAIN (x);
2847 /* Save the access declarations for our caller. */
2848 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2850 /* Since we've reset *FIELD there's no reason to skip to the
2856 if (TREE_CODE (x) == TYPE_DECL
2857 || TREE_CODE (x) == TEMPLATE_DECL)
2860 /* If we've gotten this far, it's a data member, possibly static,
2861 or an enumerator. */
2862 DECL_CONTEXT (x) = t;
2864 /* When this goes into scope, it will be a non-local reference. */
2865 DECL_NONLOCAL (x) = 1;
2867 if (TREE_CODE (t) == UNION_TYPE)
2871 If a union contains a static data member, or a member of
2872 reference type, the program is ill-formed. */
2873 if (TREE_CODE (x) == VAR_DECL)
2875 error ("%q+D may not be static because it is a member of a union", x);
2878 if (TREE_CODE (type) == REFERENCE_TYPE)
2880 error ("%q+D may not have reference type %qT because"
2881 " it is a member of a union",
2887 /* Perform error checking that did not get done in
2889 if (TREE_CODE (type) == FUNCTION_TYPE)
2891 error ("field %q+D invalidly declared function type", x);
2892 type = build_pointer_type (type);
2893 TREE_TYPE (x) = type;
2895 else if (TREE_CODE (type) == METHOD_TYPE)
2897 error ("field %q+D invalidly declared method type", x);
2898 type = build_pointer_type (type);
2899 TREE_TYPE (x) = type;
2902 if (type == error_mark_node)
2905 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
2908 /* Now it can only be a FIELD_DECL. */
2910 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
2911 CLASSTYPE_NON_AGGREGATE (t) = 1;
2913 /* If this is of reference type, check if it needs an init.
2914 Also do a little ANSI jig if necessary. */
2915 if (TREE_CODE (type) == REFERENCE_TYPE)
2917 CLASSTYPE_NON_POD_P (t) = 1;
2918 if (DECL_INITIAL (x) == NULL_TREE)
2919 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2921 /* ARM $12.6.2: [A member initializer list] (or, for an
2922 aggregate, initialization by a brace-enclosed list) is the
2923 only way to initialize nonstatic const and reference
2925 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2927 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
2929 warning (OPT_Wextra, "non-static reference %q+#D in class without a constructor", x);
2932 type = strip_array_types (type);
2934 if (TYPE_PACKED (t))
2936 if (!pod_type_p (type) && !TYPE_PACKED (type))
2940 "ignoring packed attribute because of unpacked non-POD field %q+#D",
2944 else if (TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
2945 DECL_PACKED (x) = 1;
2948 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
2949 /* We don't treat zero-width bitfields as making a class
2954 /* The class is non-empty. */
2955 CLASSTYPE_EMPTY_P (t) = 0;
2956 /* The class is not even nearly empty. */
2957 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
2958 /* If one of the data members contains an empty class,
2960 if (CLASS_TYPE_P (type)
2961 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
2962 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
2965 /* This is used by -Weffc++ (see below). Warn only for pointers
2966 to members which might hold dynamic memory. So do not warn
2967 for pointers to functions or pointers to members. */
2968 if (TYPE_PTR_P (type)
2969 && !TYPE_PTRFN_P (type)
2970 && !TYPE_PTR_TO_MEMBER_P (type))
2971 has_pointers = true;
2973 if (CLASS_TYPE_P (type))
2975 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
2976 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2977 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
2978 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
2981 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
2982 CLASSTYPE_HAS_MUTABLE (t) = 1;
2984 if (! pod_type_p (type))
2985 /* DR 148 now allows pointers to members (which are POD themselves),
2986 to be allowed in POD structs. */
2987 CLASSTYPE_NON_POD_P (t) = 1;
2989 if (! zero_init_p (type))
2990 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
2992 /* If any field is const, the structure type is pseudo-const. */
2993 if (CP_TYPE_CONST_P (type))
2995 C_TYPE_FIELDS_READONLY (t) = 1;
2996 if (DECL_INITIAL (x) == NULL_TREE)
2997 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
2999 /* ARM $12.6.2: [A member initializer list] (or, for an
3000 aggregate, initialization by a brace-enclosed list) is the
3001 only way to initialize nonstatic const and reference
3003 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3005 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
3007 warning (OPT_Wextra, "non-static const member %q+#D in class without a constructor", x);
3009 /* A field that is pseudo-const makes the structure likewise. */
3010 else if (CLASS_TYPE_P (type))
3012 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3013 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3014 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3015 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3018 /* Core issue 80: A nonstatic data member is required to have a
3019 different name from the class iff the class has a
3020 user-defined constructor. */
3021 if (constructor_name_p (DECL_NAME (x), t) && TYPE_HAS_CONSTRUCTOR (t))
3022 pedwarn ("field %q+#D with same name as class", x);
3024 /* We set DECL_C_BIT_FIELD in grokbitfield.
3025 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3026 if (DECL_C_BIT_FIELD (x))
3027 check_bitfield_decl (x);
3029 check_field_decl (x, t,
3030 cant_have_const_ctor_p,
3032 &any_default_members);
3035 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3036 it should also define a copy constructor and an assignment operator to
3037 implement the correct copy semantic (deep vs shallow, etc.). As it is
3038 not feasible to check whether the constructors do allocate dynamic memory
3039 and store it within members, we approximate the warning like this:
3041 -- Warn only if there are members which are pointers
3042 -- Warn only if there is a non-trivial constructor (otherwise,
3043 there cannot be memory allocated).
3044 -- Warn only if there is a non-trivial destructor. We assume that the
3045 user at least implemented the cleanup correctly, and a destructor
3046 is needed to free dynamic memory.
3048 This seems enough for practical purposes. */
3051 && TYPE_HAS_CONSTRUCTOR (t)
3052 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3053 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3055 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3057 if (! TYPE_HAS_INIT_REF (t))
3059 warning (OPT_Weffc__,
3060 " but does not override %<%T(const %T&)%>", t, t);
3061 if (!TYPE_HAS_ASSIGN_REF (t))
3062 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3064 else if (! TYPE_HAS_ASSIGN_REF (t))
3065 warning (OPT_Weffc__,
3066 " but does not override %<operator=(const %T&)%>", t);
3069 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3071 TYPE_PACKED (t) = 0;
3073 /* Check anonymous struct/anonymous union fields. */
3074 finish_struct_anon (t);
3076 /* We've built up the list of access declarations in reverse order.
3078 *access_decls = nreverse (*access_decls);
3081 /* If TYPE is an empty class type, records its OFFSET in the table of
3085 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3089 if (!is_empty_class (type))
3092 /* Record the location of this empty object in OFFSETS. */
3093 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3095 n = splay_tree_insert (offsets,
3096 (splay_tree_key) offset,
3097 (splay_tree_value) NULL_TREE);
3098 n->value = ((splay_tree_value)
3099 tree_cons (NULL_TREE,
3106 /* Returns nonzero if TYPE is an empty class type and there is
3107 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3110 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3115 if (!is_empty_class (type))
3118 /* Record the location of this empty object in OFFSETS. */
3119 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3123 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3124 if (same_type_p (TREE_VALUE (t), type))
3130 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3131 F for every subobject, passing it the type, offset, and table of
3132 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3135 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3136 than MAX_OFFSET will not be walked.
3138 If F returns a nonzero value, the traversal ceases, and that value
3139 is returned. Otherwise, returns zero. */
3142 walk_subobject_offsets (tree type,
3143 subobject_offset_fn f,
3150 tree type_binfo = NULL_TREE;
3152 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3154 if (max_offset && INT_CST_LT (max_offset, offset))
3157 if (type == error_mark_node)
3162 if (abi_version_at_least (2))
3164 type = BINFO_TYPE (type);
3167 if (CLASS_TYPE_P (type))
3173 /* Avoid recursing into objects that are not interesting. */
3174 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3177 /* Record the location of TYPE. */
3178 r = (*f) (type, offset, offsets);
3182 /* Iterate through the direct base classes of TYPE. */
3184 type_binfo = TYPE_BINFO (type);
3185 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3189 if (abi_version_at_least (2)
3190 && BINFO_VIRTUAL_P (binfo))
3194 && BINFO_VIRTUAL_P (binfo)
3195 && !BINFO_PRIMARY_P (binfo))
3198 if (!abi_version_at_least (2))
3199 binfo_offset = size_binop (PLUS_EXPR,
3201 BINFO_OFFSET (binfo));
3205 /* We cannot rely on BINFO_OFFSET being set for the base
3206 class yet, but the offsets for direct non-virtual
3207 bases can be calculated by going back to the TYPE. */
3208 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3209 binfo_offset = size_binop (PLUS_EXPR,
3211 BINFO_OFFSET (orig_binfo));
3214 r = walk_subobject_offsets (binfo,
3219 (abi_version_at_least (2)
3220 ? /*vbases_p=*/0 : vbases_p));
3225 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3228 VEC(tree,gc) *vbases;
3230 /* Iterate through the virtual base classes of TYPE. In G++
3231 3.2, we included virtual bases in the direct base class
3232 loop above, which results in incorrect results; the
3233 correct offsets for virtual bases are only known when
3234 working with the most derived type. */
3236 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3237 VEC_iterate (tree, vbases, ix, binfo); ix++)
3239 r = walk_subobject_offsets (binfo,
3241 size_binop (PLUS_EXPR,
3243 BINFO_OFFSET (binfo)),
3252 /* We still have to walk the primary base, if it is
3253 virtual. (If it is non-virtual, then it was walked
3255 tree vbase = get_primary_binfo (type_binfo);
3257 if (vbase && BINFO_VIRTUAL_P (vbase)
3258 && BINFO_PRIMARY_P (vbase)
3259 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3261 r = (walk_subobject_offsets
3263 offsets, max_offset, /*vbases_p=*/0));
3270 /* Iterate through the fields of TYPE. */
3271 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3272 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3276 if (abi_version_at_least (2))
3277 field_offset = byte_position (field);
3279 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3280 field_offset = DECL_FIELD_OFFSET (field);
3282 r = walk_subobject_offsets (TREE_TYPE (field),
3284 size_binop (PLUS_EXPR,
3294 else if (TREE_CODE (type) == ARRAY_TYPE)
3296 tree element_type = strip_array_types (type);
3297 tree domain = TYPE_DOMAIN (type);
3300 /* Avoid recursing into objects that are not interesting. */
3301 if (!CLASS_TYPE_P (element_type)
3302 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3305 /* Step through each of the elements in the array. */
3306 for (index = size_zero_node;
3307 /* G++ 3.2 had an off-by-one error here. */
3308 (abi_version_at_least (2)
3309 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3310 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3311 index = size_binop (PLUS_EXPR, index, size_one_node))
3313 r = walk_subobject_offsets (TREE_TYPE (type),
3321 offset = size_binop (PLUS_EXPR, offset,
3322 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3323 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3324 there's no point in iterating through the remaining
3325 elements of the array. */
3326 if (max_offset && INT_CST_LT (max_offset, offset))
3334 /* Record all of the empty subobjects of TYPE (either a type or a
3335 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3336 is being placed at OFFSET; otherwise, it is a base class that is
3337 being placed at OFFSET. */
3340 record_subobject_offsets (tree type,
3343 bool is_data_member)
3346 /* If recording subobjects for a non-static data member or a
3347 non-empty base class , we do not need to record offsets beyond
3348 the size of the biggest empty class. Additional data members
3349 will go at the end of the class. Additional base classes will go
3350 either at offset zero (if empty, in which case they cannot
3351 overlap with offsets past the size of the biggest empty class) or
3352 at the end of the class.
3354 However, if we are placing an empty base class, then we must record
3355 all offsets, as either the empty class is at offset zero (where
3356 other empty classes might later be placed) or at the end of the
3357 class (where other objects might then be placed, so other empty
3358 subobjects might later overlap). */
3360 || !is_empty_class (BINFO_TYPE (type)))
3361 max_offset = sizeof_biggest_empty_class;
3363 max_offset = NULL_TREE;
3364 walk_subobject_offsets (type, record_subobject_offset, offset,
3365 offsets, max_offset, is_data_member);
3368 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3369 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3370 virtual bases of TYPE are examined. */
3373 layout_conflict_p (tree type,
3378 splay_tree_node max_node;
3380 /* Get the node in OFFSETS that indicates the maximum offset where
3381 an empty subobject is located. */
3382 max_node = splay_tree_max (offsets);
3383 /* If there aren't any empty subobjects, then there's no point in
3384 performing this check. */
3388 return walk_subobject_offsets (type, check_subobject_offset, offset,
3389 offsets, (tree) (max_node->key),
3393 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3394 non-static data member of the type indicated by RLI. BINFO is the
3395 binfo corresponding to the base subobject, OFFSETS maps offsets to
3396 types already located at those offsets. This function determines
3397 the position of the DECL. */
3400 layout_nonempty_base_or_field (record_layout_info rli,
3405 tree offset = NULL_TREE;
3411 /* For the purposes of determining layout conflicts, we want to
3412 use the class type of BINFO; TREE_TYPE (DECL) will be the
3413 CLASSTYPE_AS_BASE version, which does not contain entries for
3414 zero-sized bases. */
3415 type = TREE_TYPE (binfo);
3420 type = TREE_TYPE (decl);
3424 /* Try to place the field. It may take more than one try if we have
3425 a hard time placing the field without putting two objects of the
3426 same type at the same address. */
3429 struct record_layout_info_s old_rli = *rli;
3431 /* Place this field. */
3432 place_field (rli, decl);
3433 offset = byte_position (decl);
3435 /* We have to check to see whether or not there is already
3436 something of the same type at the offset we're about to use.
3437 For example, consider:
3440 struct T : public S { int i; };
3441 struct U : public S, public T {};
3443 Here, we put S at offset zero in U. Then, we can't put T at
3444 offset zero -- its S component would be at the same address
3445 as the S we already allocated. So, we have to skip ahead.
3446 Since all data members, including those whose type is an
3447 empty class, have nonzero size, any overlap can happen only
3448 with a direct or indirect base-class -- it can't happen with
3450 /* In a union, overlap is permitted; all members are placed at
3452 if (TREE_CODE (rli->t) == UNION_TYPE)
3454 /* G++ 3.2 did not check for overlaps when placing a non-empty
3456 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3458 if (layout_conflict_p (field_p ? type : binfo, offset,
3461 /* Strip off the size allocated to this field. That puts us
3462 at the first place we could have put the field with
3463 proper alignment. */
3466 /* Bump up by the alignment required for the type. */
3468 = size_binop (PLUS_EXPR, rli->bitpos,
3470 ? CLASSTYPE_ALIGN (type)
3471 : TYPE_ALIGN (type)));
3472 normalize_rli (rli);
3475 /* There was no conflict. We're done laying out this field. */
3479 /* Now that we know where it will be placed, update its
3481 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3482 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3483 this point because their BINFO_OFFSET is copied from another
3484 hierarchy. Therefore, we may not need to add the entire
3486 propagate_binfo_offsets (binfo,
3487 size_diffop (convert (ssizetype, offset),
3489 BINFO_OFFSET (binfo))));
3492 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3495 empty_base_at_nonzero_offset_p (tree type,
3497 splay_tree offsets ATTRIBUTE_UNUSED)
3499 return is_empty_class (type) && !integer_zerop (offset);
3502 /* Layout the empty base BINFO. EOC indicates the byte currently just
3503 past the end of the class, and should be correctly aligned for a
3504 class of the type indicated by BINFO; OFFSETS gives the offsets of
3505 the empty bases allocated so far. T is the most derived
3506 type. Return nonzero iff we added it at the end. */
3509 layout_empty_base (tree binfo, tree eoc, splay_tree offsets)
3512 tree basetype = BINFO_TYPE (binfo);
3515 /* This routine should only be used for empty classes. */
3516 gcc_assert (is_empty_class (basetype));
3517 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3519 if (!integer_zerop (BINFO_OFFSET (binfo)))
3521 if (abi_version_at_least (2))
3522 propagate_binfo_offsets
3523 (binfo, size_diffop (size_zero_node, BINFO_OFFSET (binfo)));
3526 "offset of empty base %qT may not be ABI-compliant and may"
3527 "change in a future version of GCC",
3528 BINFO_TYPE (binfo));
3531 /* This is an empty base class. We first try to put it at offset
3533 if (layout_conflict_p (binfo,
3534 BINFO_OFFSET (binfo),
3538 /* That didn't work. Now, we move forward from the next
3539 available spot in the class. */
3541 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3544 if (!layout_conflict_p (binfo,
3545 BINFO_OFFSET (binfo),
3548 /* We finally found a spot where there's no overlap. */
3551 /* There's overlap here, too. Bump along to the next spot. */
3552 propagate_binfo_offsets (binfo, alignment);
3558 /* Layout the base given by BINFO in the class indicated by RLI.
3559 *BASE_ALIGN is a running maximum of the alignments of
3560 any base class. OFFSETS gives the location of empty base
3561 subobjects. T is the most derived type. Return nonzero if the new
3562 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3563 *NEXT_FIELD, unless BINFO is for an empty base class.
3565 Returns the location at which the next field should be inserted. */
3568 build_base_field (record_layout_info rli, tree binfo,
3569 splay_tree offsets, tree *next_field)
3572 tree basetype = BINFO_TYPE (binfo);
3574 if (!COMPLETE_TYPE_P (basetype))
3575 /* This error is now reported in xref_tag, thus giving better
3576 location information. */
3579 /* Place the base class. */
3580 if (!is_empty_class (basetype))
3584 /* The containing class is non-empty because it has a non-empty
3586 CLASSTYPE_EMPTY_P (t) = 0;
3588 /* Create the FIELD_DECL. */
3589 decl = build_decl (FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3590 DECL_ARTIFICIAL (decl) = 1;
3591 DECL_IGNORED_P (decl) = 1;
3592 DECL_FIELD_CONTEXT (decl) = t;
3593 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3594 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3595 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3596 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3597 DECL_MODE (decl) = TYPE_MODE (basetype);
3598 DECL_FIELD_IS_BASE (decl) = 1;
3600 /* Try to place the field. It may take more than one try if we
3601 have a hard time placing the field without putting two
3602 objects of the same type at the same address. */
3603 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3604 /* Add the new FIELD_DECL to the list of fields for T. */
3605 TREE_CHAIN (decl) = *next_field;
3607 next_field = &TREE_CHAIN (decl);
3614 /* On some platforms (ARM), even empty classes will not be
3616 eoc = round_up (rli_size_unit_so_far (rli),
3617 CLASSTYPE_ALIGN_UNIT (basetype));
3618 atend = layout_empty_base (binfo, eoc, offsets);
3619 /* A nearly-empty class "has no proper base class that is empty,
3620 not morally virtual, and at an offset other than zero." */
3621 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3624 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3625 /* The check above (used in G++ 3.2) is insufficient because
3626 an empty class placed at offset zero might itself have an
3627 empty base at a nonzero offset. */
3628 else if (walk_subobject_offsets (basetype,
3629 empty_base_at_nonzero_offset_p,
3632 /*max_offset=*/NULL_TREE,
3635 if (abi_version_at_least (2))
3636 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3639 "class %qT will be considered nearly empty in a "
3640 "future version of GCC", t);
3644 /* We do not create a FIELD_DECL for empty base classes because
3645 it might overlap some other field. We want to be able to
3646 create CONSTRUCTORs for the class by iterating over the
3647 FIELD_DECLs, and the back end does not handle overlapping
3650 /* An empty virtual base causes a class to be non-empty
3651 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3652 here because that was already done when the virtual table
3653 pointer was created. */
3656 /* Record the offsets of BINFO and its base subobjects. */
3657 record_subobject_offsets (binfo,
3658 BINFO_OFFSET (binfo),
3660 /*is_data_member=*/false);
3665 /* Layout all of the non-virtual base classes. Record empty
3666 subobjects in OFFSETS. T is the most derived type. Return nonzero
3667 if the type cannot be nearly empty. The fields created
3668 corresponding to the base classes will be inserted at
3672 build_base_fields (record_layout_info rli,
3673 splay_tree offsets, tree *next_field)
3675 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3678 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3681 /* The primary base class is always allocated first. */
3682 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3683 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3684 offsets, next_field);
3686 /* Now allocate the rest of the bases. */
3687 for (i = 0; i < n_baseclasses; ++i)
3691 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3693 /* The primary base was already allocated above, so we don't
3694 need to allocate it again here. */
3695 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3698 /* Virtual bases are added at the end (a primary virtual base
3699 will have already been added). */
3700 if (BINFO_VIRTUAL_P (base_binfo))
3703 next_field = build_base_field (rli, base_binfo,
3704 offsets, next_field);
3708 /* Go through the TYPE_METHODS of T issuing any appropriate
3709 diagnostics, figuring out which methods override which other
3710 methods, and so forth. */
3713 check_methods (tree t)
3717 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3719 check_for_override (x, t);
3720 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3721 error ("initializer specified for non-virtual method %q+D", x);
3722 /* The name of the field is the original field name
3723 Save this in auxiliary field for later overloading. */
3724 if (DECL_VINDEX (x))
3726 TYPE_POLYMORPHIC_P (t) = 1;
3727 if (DECL_PURE_VIRTUAL_P (x))
3728 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3730 /* All user-declared destructors are non-trivial. */
3731 if (DECL_DESTRUCTOR_P (x))
3732 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3736 /* FN is a constructor or destructor. Clone the declaration to create
3737 a specialized in-charge or not-in-charge version, as indicated by
3741 build_clone (tree fn, tree name)
3746 /* Copy the function. */
3747 clone = copy_decl (fn);
3748 /* Remember where this function came from. */
3749 DECL_CLONED_FUNCTION (clone) = fn;
3750 DECL_ABSTRACT_ORIGIN (clone) = fn;
3751 /* Reset the function name. */
3752 DECL_NAME (clone) = name;
3753 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3754 /* There's no pending inline data for this function. */
3755 DECL_PENDING_INLINE_INFO (clone) = NULL;
3756 DECL_PENDING_INLINE_P (clone) = 0;
3757 /* And it hasn't yet been deferred. */
3758 DECL_DEFERRED_FN (clone) = 0;
3760 /* The base-class destructor is not virtual. */
3761 if (name == base_dtor_identifier)
3763 DECL_VIRTUAL_P (clone) = 0;
3764 if (TREE_CODE (clone) != TEMPLATE_DECL)
3765 DECL_VINDEX (clone) = NULL_TREE;
3768 /* If there was an in-charge parameter, drop it from the function
3770 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3776 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3777 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3778 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3779 /* Skip the `this' parameter. */
3780 parmtypes = TREE_CHAIN (parmtypes);
3781 /* Skip the in-charge parameter. */
3782 parmtypes = TREE_CHAIN (parmtypes);
3783 /* And the VTT parm, in a complete [cd]tor. */
3784 if (DECL_HAS_VTT_PARM_P (fn)
3785 && ! DECL_NEEDS_VTT_PARM_P (clone))
3786 parmtypes = TREE_CHAIN (parmtypes);
3787 /* If this is subobject constructor or destructor, add the vtt
3790 = build_method_type_directly (basetype,
3791 TREE_TYPE (TREE_TYPE (clone)),
3794 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3797 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3798 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3801 /* Copy the function parameters. But, DECL_ARGUMENTS on a TEMPLATE_DECL
3802 aren't function parameters; those are the template parameters. */
3803 if (TREE_CODE (clone) != TEMPLATE_DECL)
3805 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3806 /* Remove the in-charge parameter. */
3807 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3809 TREE_CHAIN (DECL_ARGUMENTS (clone))
3810 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3811 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3813 /* And the VTT parm, in a complete [cd]tor. */
3814 if (DECL_HAS_VTT_PARM_P (fn))
3816 if (DECL_NEEDS_VTT_PARM_P (clone))
3817 DECL_HAS_VTT_PARM_P (clone) = 1;
3820 TREE_CHAIN (DECL_ARGUMENTS (clone))
3821 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3822 DECL_HAS_VTT_PARM_P (clone) = 0;
3826 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3828 DECL_CONTEXT (parms) = clone;
3829 cxx_dup_lang_specific_decl (parms);
3833 /* Create the RTL for this function. */
3834 SET_DECL_RTL (clone, NULL_RTX);
3835 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3837 /* Make it easy to find the CLONE given the FN. */
3838 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3839 TREE_CHAIN (fn) = clone;
3841 /* If this is a template, handle the DECL_TEMPLATE_RESULT as well. */
3842 if (TREE_CODE (clone) == TEMPLATE_DECL)
3846 DECL_TEMPLATE_RESULT (clone)
3847 = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3848 result = DECL_TEMPLATE_RESULT (clone);
3849 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3850 DECL_TI_TEMPLATE (result) = clone;
3853 note_decl_for_pch (clone);
3858 /* Produce declarations for all appropriate clones of FN. If
3859 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
3860 CLASTYPE_METHOD_VEC as well. */
3863 clone_function_decl (tree fn, int update_method_vec_p)
3867 /* Avoid inappropriate cloning. */
3869 && DECL_CLONED_FUNCTION (TREE_CHAIN (fn)))
3872 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
3874 /* For each constructor, we need two variants: an in-charge version
3875 and a not-in-charge version. */
3876 clone = build_clone (fn, complete_ctor_identifier);
3877 if (update_method_vec_p)
3878 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3879 clone = build_clone (fn, base_ctor_identifier);
3880 if (update_method_vec_p)
3881 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3885 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
3887 /* For each destructor, we need three variants: an in-charge
3888 version, a not-in-charge version, and an in-charge deleting
3889 version. We clone the deleting version first because that
3890 means it will go second on the TYPE_METHODS list -- and that
3891 corresponds to the correct layout order in the virtual
3894 For a non-virtual destructor, we do not build a deleting
3896 if (DECL_VIRTUAL_P (fn))
3898 clone = build_clone (fn, deleting_dtor_identifier);
3899 if (update_method_vec_p)
3900 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3902 clone = build_clone (fn, complete_dtor_identifier);
3903 if (update_method_vec_p)
3904 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3905 clone = build_clone (fn, base_dtor_identifier);
3906 if (update_method_vec_p)
3907 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3910 /* Note that this is an abstract function that is never emitted. */
3911 DECL_ABSTRACT (fn) = 1;
3914 /* DECL is an in charge constructor, which is being defined. This will
3915 have had an in class declaration, from whence clones were
3916 declared. An out-of-class definition can specify additional default
3917 arguments. As it is the clones that are involved in overload
3918 resolution, we must propagate the information from the DECL to its
3922 adjust_clone_args (tree decl)
3926 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION (clone);
3927 clone = TREE_CHAIN (clone))
3929 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
3930 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
3931 tree decl_parms, clone_parms;
3933 clone_parms = orig_clone_parms;
3935 /* Skip the 'this' parameter. */
3936 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
3937 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3939 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
3940 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3941 if (DECL_HAS_VTT_PARM_P (decl))
3942 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3944 clone_parms = orig_clone_parms;
3945 if (DECL_HAS_VTT_PARM_P (clone))
3946 clone_parms = TREE_CHAIN (clone_parms);
3948 for (decl_parms = orig_decl_parms; decl_parms;
3949 decl_parms = TREE_CHAIN (decl_parms),
3950 clone_parms = TREE_CHAIN (clone_parms))
3952 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
3953 TREE_TYPE (clone_parms)));
3955 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
3957 /* A default parameter has been added. Adjust the
3958 clone's parameters. */
3959 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3960 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3963 clone_parms = orig_decl_parms;
3965 if (DECL_HAS_VTT_PARM_P (clone))
3967 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
3968 TREE_VALUE (orig_clone_parms),
3970 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
3972 type = build_method_type_directly (basetype,
3973 TREE_TYPE (TREE_TYPE (clone)),
3976 type = build_exception_variant (type, exceptions);
3977 TREE_TYPE (clone) = type;
3979 clone_parms = NULL_TREE;
3983 gcc_assert (!clone_parms);
3987 /* For each of the constructors and destructors in T, create an
3988 in-charge and not-in-charge variant. */
3991 clone_constructors_and_destructors (tree t)
3995 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
3997 if (!CLASSTYPE_METHOD_VEC (t))
4000 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4001 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4002 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4003 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4006 /* Remove all zero-width bit-fields from T. */
4009 remove_zero_width_bit_fields (tree t)
4013 fieldsp = &TYPE_FIELDS (t);
4016 if (TREE_CODE (*fieldsp) == FIELD_DECL
4017 && DECL_C_BIT_FIELD (*fieldsp)
4018 && DECL_INITIAL (*fieldsp))
4019 *fieldsp = TREE_CHAIN (*fieldsp);
4021 fieldsp = &TREE_CHAIN (*fieldsp);
4025 /* Returns TRUE iff we need a cookie when dynamically allocating an
4026 array whose elements have the indicated class TYPE. */
4029 type_requires_array_cookie (tree type)
4032 bool has_two_argument_delete_p = false;
4034 gcc_assert (CLASS_TYPE_P (type));
4036 /* If there's a non-trivial destructor, we need a cookie. In order
4037 to iterate through the array calling the destructor for each
4038 element, we'll have to know how many elements there are. */
4039 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4042 /* If the usual deallocation function is a two-argument whose second
4043 argument is of type `size_t', then we have to pass the size of
4044 the array to the deallocation function, so we will need to store
4046 fns = lookup_fnfields (TYPE_BINFO (type),
4047 ansi_opname (VEC_DELETE_EXPR),
4049 /* If there are no `operator []' members, or the lookup is
4050 ambiguous, then we don't need a cookie. */
4051 if (!fns || fns == error_mark_node)
4053 /* Loop through all of the functions. */
4054 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4059 /* Select the current function. */
4060 fn = OVL_CURRENT (fns);
4061 /* See if this function is a one-argument delete function. If
4062 it is, then it will be the usual deallocation function. */
4063 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4064 if (second_parm == void_list_node)
4066 /* Otherwise, if we have a two-argument function and the second
4067 argument is `size_t', it will be the usual deallocation
4068 function -- unless there is one-argument function, too. */
4069 if (TREE_CHAIN (second_parm) == void_list_node
4070 && same_type_p (TREE_VALUE (second_parm), sizetype))
4071 has_two_argument_delete_p = true;
4074 return has_two_argument_delete_p;
4077 /* Check the validity of the bases and members declared in T. Add any
4078 implicitly-generated functions (like copy-constructors and
4079 assignment operators). Compute various flag bits (like
4080 CLASSTYPE_NON_POD_T) for T. This routine works purely at the C++
4081 level: i.e., independently of the ABI in use. */
4084 check_bases_and_members (tree t)
4086 /* Nonzero if the implicitly generated copy constructor should take
4087 a non-const reference argument. */
4088 int cant_have_const_ctor;
4089 /* Nonzero if the implicitly generated assignment operator
4090 should take a non-const reference argument. */
4091 int no_const_asn_ref;
4094 /* By default, we use const reference arguments and generate default
4096 cant_have_const_ctor = 0;
4097 no_const_asn_ref = 0;
4099 /* Check all the base-classes. */
4100 check_bases (t, &cant_have_const_ctor,
4103 /* Check all the method declarations. */
4106 /* Check all the data member declarations. We cannot call
4107 check_field_decls until we have called check_bases check_methods,
4108 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4109 being set appropriately. */
4110 check_field_decls (t, &access_decls,
4111 &cant_have_const_ctor,
4114 /* A nearly-empty class has to be vptr-containing; a nearly empty
4115 class contains just a vptr. */
4116 if (!TYPE_CONTAINS_VPTR_P (t))
4117 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4119 /* Do some bookkeeping that will guide the generation of implicitly
4120 declared member functions. */
4121 TYPE_HAS_COMPLEX_INIT_REF (t)
4122 |= (TYPE_HAS_INIT_REF (t) || TYPE_CONTAINS_VPTR_P (t));
4123 TYPE_NEEDS_CONSTRUCTING (t)
4124 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_CONTAINS_VPTR_P (t));
4125 CLASSTYPE_NON_AGGREGATE (t)
4126 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_POLYMORPHIC_P (t));
4127 CLASSTYPE_NON_POD_P (t)
4128 |= (CLASSTYPE_NON_AGGREGATE (t)
4129 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
4130 || TYPE_HAS_ASSIGN_REF (t));
4131 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
4132 |= TYPE_HAS_ASSIGN_REF (t) || TYPE_CONTAINS_VPTR_P (t);
4134 /* Synthesize any needed methods. */
4135 add_implicitly_declared_members (t,
4136 cant_have_const_ctor,
4139 /* Create the in-charge and not-in-charge variants of constructors
4141 clone_constructors_and_destructors (t);
4143 /* Process the using-declarations. */
4144 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4145 handle_using_decl (TREE_VALUE (access_decls), t);
4147 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4148 finish_struct_methods (t);
4150 /* Figure out whether or not we will need a cookie when dynamically
4151 allocating an array of this type. */
4152 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4153 = type_requires_array_cookie (t);
4156 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4157 accordingly. If a new vfield was created (because T doesn't have a
4158 primary base class), then the newly created field is returned. It
4159 is not added to the TYPE_FIELDS list; it is the caller's
4160 responsibility to do that. Accumulate declared virtual functions
4164 create_vtable_ptr (tree t, tree* virtuals_p)
4168 /* Collect the virtual functions declared in T. */
4169 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4170 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4171 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4173 tree new_virtual = make_node (TREE_LIST);
4175 BV_FN (new_virtual) = fn;
4176 BV_DELTA (new_virtual) = integer_zero_node;
4177 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4179 TREE_CHAIN (new_virtual) = *virtuals_p;
4180 *virtuals_p = new_virtual;
4183 /* If we couldn't find an appropriate base class, create a new field
4184 here. Even if there weren't any new virtual functions, we might need a
4185 new virtual function table if we're supposed to include vptrs in
4186 all classes that need them. */
4187 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4189 /* We build this decl with vtbl_ptr_type_node, which is a
4190 `vtable_entry_type*'. It might seem more precise to use
4191 `vtable_entry_type (*)[N]' where N is the number of virtual
4192 functions. However, that would require the vtable pointer in
4193 base classes to have a different type than the vtable pointer
4194 in derived classes. We could make that happen, but that
4195 still wouldn't solve all the problems. In particular, the
4196 type-based alias analysis code would decide that assignments
4197 to the base class vtable pointer can't alias assignments to
4198 the derived class vtable pointer, since they have different
4199 types. Thus, in a derived class destructor, where the base
4200 class constructor was inlined, we could generate bad code for
4201 setting up the vtable pointer.
4203 Therefore, we use one type for all vtable pointers. We still
4204 use a type-correct type; it's just doesn't indicate the array
4205 bounds. That's better than using `void*' or some such; it's
4206 cleaner, and it let's the alias analysis code know that these
4207 stores cannot alias stores to void*! */
4210 field = build_decl (FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4211 DECL_VIRTUAL_P (field) = 1;
4212 DECL_ARTIFICIAL (field) = 1;
4213 DECL_FIELD_CONTEXT (field) = t;
4214 DECL_FCONTEXT (field) = t;
4216 TYPE_VFIELD (t) = field;
4218 /* This class is non-empty. */
4219 CLASSTYPE_EMPTY_P (t) = 0;
4227 /* Fixup the inline function given by INFO now that the class is
4231 fixup_pending_inline (tree fn)
4233 if (DECL_PENDING_INLINE_INFO (fn))
4235 tree args = DECL_ARGUMENTS (fn);
4238 DECL_CONTEXT (args) = fn;
4239 args = TREE_CHAIN (args);
4244 /* Fixup the inline methods and friends in TYPE now that TYPE is
4248 fixup_inline_methods (tree type)
4250 tree method = TYPE_METHODS (type);
4251 VEC(tree,gc) *friends;
4254 if (method && TREE_CODE (method) == TREE_VEC)
4256 if (TREE_VEC_ELT (method, 1))
4257 method = TREE_VEC_ELT (method, 1);
4258 else if (TREE_VEC_ELT (method, 0))
4259 method = TREE_VEC_ELT (method, 0);
4261 method = TREE_VEC_ELT (method, 2);
4264 /* Do inline member functions. */
4265 for (; method; method = TREE_CHAIN (method))
4266 fixup_pending_inline (method);
4269 for (friends = CLASSTYPE_INLINE_FRIENDS (type), ix = 0;
4270 VEC_iterate (tree, friends, ix, method); ix++)
4271 fixup_pending_inline (method);
4272 CLASSTYPE_INLINE_FRIENDS (type) = NULL;
4275 /* Add OFFSET to all base types of BINFO which is a base in the
4276 hierarchy dominated by T.
4278 OFFSET, which is a type offset, is number of bytes. */
4281 propagate_binfo_offsets (tree binfo, tree offset)
4287 /* Update BINFO's offset. */
4288 BINFO_OFFSET (binfo)
4289 = convert (sizetype,
4290 size_binop (PLUS_EXPR,
4291 convert (ssizetype, BINFO_OFFSET (binfo)),
4294 /* Find the primary base class. */
4295 primary_binfo = get_primary_binfo (binfo);
4297 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4298 propagate_binfo_offsets (primary_binfo, offset);
4300 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4302 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4304 /* Don't do the primary base twice. */
4305 if (base_binfo == primary_binfo)
4308 if (BINFO_VIRTUAL_P (base_binfo))
4311 propagate_binfo_offsets (base_binfo, offset);
4315 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4316 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4317 empty subobjects of T. */
4320 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4324 bool first_vbase = true;
4327 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4330 if (!abi_version_at_least(2))
4332 /* In G++ 3.2, we incorrectly rounded the size before laying out
4333 the virtual bases. */
4334 finish_record_layout (rli, /*free_p=*/false);
4335 #ifdef STRUCTURE_SIZE_BOUNDARY
4336 /* Packed structures don't need to have minimum size. */
4337 if (! TYPE_PACKED (t))
4338 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4340 rli->offset = TYPE_SIZE_UNIT (t);
4341 rli->bitpos = bitsize_zero_node;
4342 rli->record_align = TYPE_ALIGN (t);
4345 /* Find the last field. The artificial fields created for virtual
4346 bases will go after the last extant field to date. */
4347 next_field = &TYPE_FIELDS (t);
4349 next_field = &TREE_CHAIN (*next_field);
4351 /* Go through the virtual bases, allocating space for each virtual
4352 base that is not already a primary base class. These are
4353 allocated in inheritance graph order. */
4354 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4356 if (!BINFO_VIRTUAL_P (vbase))
4359 if (!BINFO_PRIMARY_P (vbase))
4361 tree basetype = TREE_TYPE (vbase);
4363 /* This virtual base is not a primary base of any class in the
4364 hierarchy, so we have to add space for it. */
4365 next_field = build_base_field (rli, vbase,
4366 offsets, next_field);
4368 /* If the first virtual base might have been placed at a
4369 lower address, had we started from CLASSTYPE_SIZE, rather
4370 than TYPE_SIZE, issue a warning. There can be both false
4371 positives and false negatives from this warning in rare
4372 cases; to deal with all the possibilities would probably
4373 require performing both layout algorithms and comparing
4374 the results which is not particularly tractable. */
4378 (size_binop (CEIL_DIV_EXPR,
4379 round_up (CLASSTYPE_SIZE (t),
4380 CLASSTYPE_ALIGN (basetype)),
4382 BINFO_OFFSET (vbase))))
4384 "offset of virtual base %qT is not ABI-compliant and "
4385 "may change in a future version of GCC",
4388 first_vbase = false;
4393 /* Returns the offset of the byte just past the end of the base class
4397 end_of_base (tree binfo)
4401 if (is_empty_class (BINFO_TYPE (binfo)))
4402 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4403 allocate some space for it. It cannot have virtual bases, so
4404 TYPE_SIZE_UNIT is fine. */
4405 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4407 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4409 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4412 /* Returns the offset of the byte just past the end of the base class
4413 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4414 only non-virtual bases are included. */
4417 end_of_class (tree t, int include_virtuals_p)
4419 tree result = size_zero_node;
4420 VEC(tree,gc) *vbases;
4426 for (binfo = TYPE_BINFO (t), i = 0;
4427 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4429 if (!include_virtuals_p
4430 && BINFO_VIRTUAL_P (base_binfo)
4431 && (!BINFO_PRIMARY_P (base_binfo)
4432 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4435 offset = end_of_base (base_binfo);
4436 if (INT_CST_LT_UNSIGNED (result, offset))
4440 /* G++ 3.2 did not check indirect virtual bases. */
4441 if (abi_version_at_least (2) && include_virtuals_p)
4442 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4443 VEC_iterate (tree, vbases, i, base_binfo); i++)
4445 offset = end_of_base (base_binfo);
4446 if (INT_CST_LT_UNSIGNED (result, offset))
4453 /* Warn about bases of T that are inaccessible because they are
4454 ambiguous. For example:
4457 struct T : public S {};
4458 struct U : public S, public T {};
4460 Here, `(S*) new U' is not allowed because there are two `S'
4464 warn_about_ambiguous_bases (tree t)
4467 VEC(tree,gc) *vbases;
4472 /* If there are no repeated bases, nothing can be ambiguous. */
4473 if (!CLASSTYPE_REPEATED_BASE_P (t))
4476 /* Check direct bases. */
4477 for (binfo = TYPE_BINFO (t), i = 0;
4478 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4480 basetype = BINFO_TYPE (base_binfo);
4482 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4483 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4487 /* Check for ambiguous virtual bases. */
4489 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4490 VEC_iterate (tree, vbases, i, binfo); i++)
4492 basetype = BINFO_TYPE (binfo);
4494 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4495 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4500 /* Compare two INTEGER_CSTs K1 and K2. */
4503 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4505 return tree_int_cst_compare ((tree) k1, (tree) k2);
4508 /* Increase the size indicated in RLI to account for empty classes
4509 that are "off the end" of the class. */
4512 include_empty_classes (record_layout_info rli)
4517 /* It might be the case that we grew the class to allocate a
4518 zero-sized base class. That won't be reflected in RLI, yet,
4519 because we are willing to overlay multiple bases at the same
4520 offset. However, now we need to make sure that RLI is big enough
4521 to reflect the entire class. */
4522 eoc = end_of_class (rli->t,
4523 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4524 rli_size = rli_size_unit_so_far (rli);
4525 if (TREE_CODE (rli_size) == INTEGER_CST
4526 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4528 if (!abi_version_at_least (2))
4529 /* In version 1 of the ABI, the size of a class that ends with
4530 a bitfield was not rounded up to a whole multiple of a
4531 byte. Because rli_size_unit_so_far returns only the number
4532 of fully allocated bytes, any extra bits were not included
4534 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4536 /* The size should have been rounded to a whole byte. */
4537 gcc_assert (tree_int_cst_equal
4538 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4540 = size_binop (PLUS_EXPR,
4542 size_binop (MULT_EXPR,
4543 convert (bitsizetype,
4544 size_binop (MINUS_EXPR,
4546 bitsize_int (BITS_PER_UNIT)));
4547 normalize_rli (rli);
4551 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4552 BINFO_OFFSETs for all of the base-classes. Position the vtable
4553 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4556 layout_class_type (tree t, tree *virtuals_p)
4558 tree non_static_data_members;
4561 record_layout_info rli;
4562 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4563 types that appear at that offset. */
4564 splay_tree empty_base_offsets;
4565 /* True if the last field layed out was a bit-field. */
4566 bool last_field_was_bitfield = false;
4567 /* The location at which the next field should be inserted. */
4569 /* T, as a base class. */
4572 /* Keep track of the first non-static data member. */
4573 non_static_data_members = TYPE_FIELDS (t);
4575 /* Start laying out the record. */
4576 rli = start_record_layout (t);
4578 /* Mark all the primary bases in the hierarchy. */
4579 determine_primary_bases (t);
4581 /* Create a pointer to our virtual function table. */
4582 vptr = create_vtable_ptr (t, virtuals_p);
4584 /* The vptr is always the first thing in the class. */
4587 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4588 TYPE_FIELDS (t) = vptr;
4589 next_field = &TREE_CHAIN (vptr);
4590 place_field (rli, vptr);
4593 next_field = &TYPE_FIELDS (t);
4595 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4596 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4598 build_base_fields (rli, empty_base_offsets, next_field);
4600 /* Layout the non-static data members. */
4601 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4606 /* We still pass things that aren't non-static data members to
4607 the back-end, in case it wants to do something with them. */
4608 if (TREE_CODE (field) != FIELD_DECL)
4610 place_field (rli, field);
4611 /* If the static data member has incomplete type, keep track
4612 of it so that it can be completed later. (The handling
4613 of pending statics in finish_record_layout is
4614 insufficient; consider:
4617 struct S2 { static S1 s1; };
4619 At this point, finish_record_layout will be called, but
4620 S1 is still incomplete.) */
4621 if (TREE_CODE (field) == VAR_DECL)
4623 maybe_register_incomplete_var (field);
4624 /* The visibility of static data members is determined
4625 at their point of declaration, not their point of
4627 determine_visibility (field);
4632 type = TREE_TYPE (field);
4633 if (type == error_mark_node)
4636 padding = NULL_TREE;
4638 /* If this field is a bit-field whose width is greater than its
4639 type, then there are some special rules for allocating
4641 if (DECL_C_BIT_FIELD (field)
4642 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4644 integer_type_kind itk;
4646 bool was_unnamed_p = false;
4647 /* We must allocate the bits as if suitably aligned for the
4648 longest integer type that fits in this many bits. type
4649 of the field. Then, we are supposed to use the left over
4650 bits as additional padding. */
4651 for (itk = itk_char; itk != itk_none; ++itk)
4652 if (INT_CST_LT (DECL_SIZE (field),
4653 TYPE_SIZE (integer_types[itk])))
4656 /* ITK now indicates a type that is too large for the
4657 field. We have to back up by one to find the largest
4659 integer_type = integer_types[itk - 1];
4661 /* Figure out how much additional padding is required. GCC
4662 3.2 always created a padding field, even if it had zero
4664 if (!abi_version_at_least (2)
4665 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4667 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4668 /* In a union, the padding field must have the full width
4669 of the bit-field; all fields start at offset zero. */
4670 padding = DECL_SIZE (field);
4673 if (TREE_CODE (t) == UNION_TYPE)
4674 warning (OPT_Wabi, "size assigned to %qT may not be "
4675 "ABI-compliant and may change in a future "
4678 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4679 TYPE_SIZE (integer_type));
4682 #ifdef PCC_BITFIELD_TYPE_MATTERS
4683 /* An unnamed bitfield does not normally affect the
4684 alignment of the containing class on a target where
4685 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4686 make any exceptions for unnamed bitfields when the
4687 bitfields are longer than their types. Therefore, we
4688 temporarily give the field a name. */
4689 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4691 was_unnamed_p = true;
4692 DECL_NAME (field) = make_anon_name ();
4695 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4696 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4697 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4698 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4699 empty_base_offsets);
4701 DECL_NAME (field) = NULL_TREE;
4702 /* Now that layout has been performed, set the size of the
4703 field to the size of its declared type; the rest of the
4704 field is effectively invisible. */
4705 DECL_SIZE (field) = TYPE_SIZE (type);
4706 /* We must also reset the DECL_MODE of the field. */
4707 if (abi_version_at_least (2))
4708 DECL_MODE (field) = TYPE_MODE (type);
4710 && DECL_MODE (field) != TYPE_MODE (type))
4711 /* Versions of G++ before G++ 3.4 did not reset the
4714 "the offset of %qD may not be ABI-compliant and may "
4715 "change in a future version of GCC", field);
4718 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4719 empty_base_offsets);
4721 /* Remember the location of any empty classes in FIELD. */
4722 if (abi_version_at_least (2))
4723 record_subobject_offsets (TREE_TYPE (field),
4724 byte_position(field),
4726 /*is_data_member=*/true);
4728 /* If a bit-field does not immediately follow another bit-field,
4729 and yet it starts in the middle of a byte, we have failed to
4730 comply with the ABI. */
4732 && DECL_C_BIT_FIELD (field)
4733 /* The TREE_NO_WARNING flag gets set by Objective-C when
4734 laying out an Objective-C class. The ObjC ABI differs
4735 from the C++ ABI, and so we do not want a warning
4737 && !TREE_NO_WARNING (field)
4738 && !last_field_was_bitfield
4739 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
4740 DECL_FIELD_BIT_OFFSET (field),
4741 bitsize_unit_node)))
4742 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
4743 "change in a future version of GCC", field);
4745 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
4746 offset of the field. */
4748 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
4749 byte_position (field))
4750 && contains_empty_class_p (TREE_TYPE (field)))
4751 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
4752 "classes to be placed at different locations in a "
4753 "future version of GCC", field);
4755 /* The middle end uses the type of expressions to determine the
4756 possible range of expression values. In order to optimize
4757 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
4758 must be made aware of the width of "i", via its type.
4760 Because C++ does not have integer types of arbitrary width,
4761 we must (for the purposes of the front end) convert from the
4762 type assigned here to the declared type of the bitfield
4763 whenever a bitfield expression is used as an rvalue.
4764 Similarly, when assigning a value to a bitfield, the value
4765 must be converted to the type given the bitfield here. */
4766 if (DECL_C_BIT_FIELD (field))
4769 unsigned HOST_WIDE_INT width;
4770 ftype = TREE_TYPE (field);
4771 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
4772 if (width != TYPE_PRECISION (ftype))
4774 = c_build_bitfield_integer_type (width,
4775 TYPE_UNSIGNED (ftype));
4778 /* If we needed additional padding after this field, add it
4784 padding_field = build_decl (FIELD_DECL,
4787 DECL_BIT_FIELD (padding_field) = 1;
4788 DECL_SIZE (padding_field) = padding;
4789 DECL_CONTEXT (padding_field) = t;
4790 DECL_ARTIFICIAL (padding_field) = 1;
4791 DECL_IGNORED_P (padding_field) = 1;
4792 layout_nonempty_base_or_field (rli, padding_field,
4794 empty_base_offsets);
4797 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
4800 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
4802 /* Make sure that we are on a byte boundary so that the size of
4803 the class without virtual bases will always be a round number
4805 rli->bitpos = round_up (rli->bitpos, BITS_PER_UNIT);
4806 normalize_rli (rli);
4809 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
4811 if (!abi_version_at_least (2))
4812 include_empty_classes(rli);
4814 /* Delete all zero-width bit-fields from the list of fields. Now
4815 that the type is laid out they are no longer important. */
4816 remove_zero_width_bit_fields (t);
4818 /* Create the version of T used for virtual bases. We do not use
4819 make_aggr_type for this version; this is an artificial type. For
4820 a POD type, we just reuse T. */
4821 if (CLASSTYPE_NON_POD_P (t) || CLASSTYPE_EMPTY_P (t))
4823 base_t = make_node (TREE_CODE (t));
4825 /* Set the size and alignment for the new type. In G++ 3.2, all
4826 empty classes were considered to have size zero when used as
4828 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
4830 TYPE_SIZE (base_t) = bitsize_zero_node;
4831 TYPE_SIZE_UNIT (base_t) = size_zero_node;
4832 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
4834 "layout of classes derived from empty class %qT "
4835 "may change in a future version of GCC",
4842 /* If the ABI version is not at least two, and the last
4843 field was a bit-field, RLI may not be on a byte
4844 boundary. In particular, rli_size_unit_so_far might
4845 indicate the last complete byte, while rli_size_so_far
4846 indicates the total number of bits used. Therefore,
4847 rli_size_so_far, rather than rli_size_unit_so_far, is
4848 used to compute TYPE_SIZE_UNIT. */
4849 eoc = end_of_class (t, /*include_virtuals_p=*/0);
4850 TYPE_SIZE_UNIT (base_t)
4851 = size_binop (MAX_EXPR,
4853 size_binop (CEIL_DIV_EXPR,
4854 rli_size_so_far (rli),
4855 bitsize_int (BITS_PER_UNIT))),
4858 = size_binop (MAX_EXPR,
4859 rli_size_so_far (rli),
4860 size_binop (MULT_EXPR,
4861 convert (bitsizetype, eoc),
4862 bitsize_int (BITS_PER_UNIT)));
4864 TYPE_ALIGN (base_t) = rli->record_align;
4865 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
4867 /* Copy the fields from T. */
4868 next_field = &TYPE_FIELDS (base_t);
4869 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4870 if (TREE_CODE (field) == FIELD_DECL)
4872 *next_field = build_decl (FIELD_DECL,
4875 DECL_CONTEXT (*next_field) = base_t;
4876 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
4877 DECL_FIELD_BIT_OFFSET (*next_field)
4878 = DECL_FIELD_BIT_OFFSET (field);
4879 DECL_SIZE (*next_field) = DECL_SIZE (field);
4880 DECL_MODE (*next_field) = DECL_MODE (field);
4881 next_field = &TREE_CHAIN (*next_field);
4884 /* Record the base version of the type. */
4885 CLASSTYPE_AS_BASE (t) = base_t;
4886 TYPE_CONTEXT (base_t) = t;
4889 CLASSTYPE_AS_BASE (t) = t;
4891 /* Every empty class contains an empty class. */
4892 if (CLASSTYPE_EMPTY_P (t))
4893 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
4895 /* Set the TYPE_DECL for this type to contain the right
4896 value for DECL_OFFSET, so that we can use it as part
4897 of a COMPONENT_REF for multiple inheritance. */
4898 layout_decl (TYPE_MAIN_DECL (t), 0);
4900 /* Now fix up any virtual base class types that we left lying
4901 around. We must get these done before we try to lay out the
4902 virtual function table. As a side-effect, this will remove the
4903 base subobject fields. */
4904 layout_virtual_bases (rli, empty_base_offsets);
4906 /* Make sure that empty classes are reflected in RLI at this
4908 include_empty_classes(rli);
4910 /* Make sure not to create any structures with zero size. */
4911 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
4913 build_decl (FIELD_DECL, NULL_TREE, char_type_node));
4915 /* Let the back-end lay out the type. */
4916 finish_record_layout (rli, /*free_p=*/true);
4918 /* Warn about bases that can't be talked about due to ambiguity. */
4919 warn_about_ambiguous_bases (t);
4921 /* Now that we're done with layout, give the base fields the real types. */
4922 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4923 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
4924 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
4927 splay_tree_delete (empty_base_offsets);
4929 if (CLASSTYPE_EMPTY_P (t)
4930 && tree_int_cst_lt (sizeof_biggest_empty_class,
4931 TYPE_SIZE_UNIT (t)))
4932 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
4935 /* Determine the "key method" for the class type indicated by TYPE,
4936 and set CLASSTYPE_KEY_METHOD accordingly. */
4939 determine_key_method (tree type)
4943 if (TYPE_FOR_JAVA (type)
4944 || processing_template_decl
4945 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
4946 || CLASSTYPE_INTERFACE_KNOWN (type))
4949 /* The key method is the first non-pure virtual function that is not
4950 inline at the point of class definition. On some targets the
4951 key function may not be inline; those targets should not call
4952 this function until the end of the translation unit. */
4953 for (method = TYPE_METHODS (type); method != NULL_TREE;
4954 method = TREE_CHAIN (method))
4955 if (DECL_VINDEX (method) != NULL_TREE
4956 && ! DECL_DECLARED_INLINE_P (method)
4957 && ! DECL_PURE_VIRTUAL_P (method))
4959 CLASSTYPE_KEY_METHOD (type) = method;
4966 /* Perform processing required when the definition of T (a class type)
4970 finish_struct_1 (tree t)
4973 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
4974 tree virtuals = NULL_TREE;
4977 if (COMPLETE_TYPE_P (t))
4979 gcc_assert (IS_AGGR_TYPE (t));
4980 error ("redefinition of %q#T", t);
4985 /* If this type was previously laid out as a forward reference,
4986 make sure we lay it out again. */
4987 TYPE_SIZE (t) = NULL_TREE;
4988 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
4990 fixup_inline_methods (t);
4992 /* Make assumptions about the class; we'll reset the flags if
4994 CLASSTYPE_EMPTY_P (t) = 1;
4995 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
4996 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
4998 /* Do end-of-class semantic processing: checking the validity of the
4999 bases and members and add implicitly generated methods. */
5000 check_bases_and_members (t);
5002 /* Find the key method. */
5003 if (TYPE_CONTAINS_VPTR_P (t))
5005 /* The Itanium C++ ABI permits the key method to be chosen when
5006 the class is defined -- even though the key method so
5007 selected may later turn out to be an inline function. On
5008 some systems (such as ARM Symbian OS) the key method cannot
5009 be determined until the end of the translation unit. On such
5010 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5011 will cause the class to be added to KEYED_CLASSES. Then, in
5012 finish_file we will determine the key method. */
5013 if (targetm.cxx.key_method_may_be_inline ())
5014 determine_key_method (t);
5016 /* If a polymorphic class has no key method, we may emit the vtable
5017 in every translation unit where the class definition appears. */
5018 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5019 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5022 /* Layout the class itself. */
5023 layout_class_type (t, &virtuals);
5024 if (CLASSTYPE_AS_BASE (t) != t)
5025 /* We use the base type for trivial assignments, and hence it
5027 compute_record_mode (CLASSTYPE_AS_BASE (t));
5029 virtuals = modify_all_vtables (t, nreverse (virtuals));
5031 /* If necessary, create the primary vtable for this class. */
5032 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5034 /* We must enter these virtuals into the table. */
5035 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5036 build_primary_vtable (NULL_TREE, t);
5037 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5038 /* Here we know enough to change the type of our virtual
5039 function table, but we will wait until later this function. */
5040 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5043 if (TYPE_CONTAINS_VPTR_P (t))
5048 if (BINFO_VTABLE (TYPE_BINFO (t)))
5049 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5050 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5051 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5053 /* Add entries for virtual functions introduced by this class. */
5054 BINFO_VIRTUALS (TYPE_BINFO (t))
5055 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5057 /* Set DECL_VINDEX for all functions declared in this class. */
5058 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5060 fn = TREE_CHAIN (fn),
5061 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5062 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5064 tree fndecl = BV_FN (fn);
5066 if (DECL_THUNK_P (fndecl))
5067 /* A thunk. We should never be calling this entry directly
5068 from this vtable -- we'd use the entry for the non
5069 thunk base function. */
5070 DECL_VINDEX (fndecl) = NULL_TREE;
5071 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5072 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5076 finish_struct_bits (t);
5078 /* Complete the rtl for any static member objects of the type we're
5080 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5081 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5082 && TREE_TYPE (x) != error_mark_node
5083 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5084 DECL_MODE (x) = TYPE_MODE (t);
5086 /* Done with FIELDS...now decide whether to sort these for
5087 faster lookups later.
5089 We use a small number because most searches fail (succeeding
5090 ultimately as the search bores through the inheritance
5091 hierarchy), and we want this failure to occur quickly. */
5093 n_fields = count_fields (TYPE_FIELDS (t));
5096 struct sorted_fields_type *field_vec = GGC_NEWVAR
5097 (struct sorted_fields_type,
5098 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5099 field_vec->len = n_fields;
5100 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5101 qsort (field_vec->elts, n_fields, sizeof (tree),
5103 if (! DECL_LANG_SPECIFIC (TYPE_MAIN_DECL (t)))
5104 retrofit_lang_decl (TYPE_MAIN_DECL (t));
5105 DECL_SORTED_FIELDS (TYPE_MAIN_DECL (t)) = field_vec;
5108 /* Complain if one of the field types requires lower visibility. */
5109 constrain_class_visibility (t);
5111 /* Make the rtl for any new vtables we have created, and unmark
5112 the base types we marked. */
5115 /* Build the VTT for T. */
5118 /* This warning does not make sense for Java classes, since they
5119 cannot have destructors. */
5120 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5124 dtor = CLASSTYPE_DESTRUCTORS (t);
5125 /* Warn only if the dtor is non-private or the class has
5127 if (/* An implicitly declared destructor is always public. And,
5128 if it were virtual, we would have created it by now. */
5130 || (!DECL_VINDEX (dtor)
5131 && (!TREE_PRIVATE (dtor)
5132 || CLASSTYPE_FRIEND_CLASSES (t)
5133 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))
5134 warning (0, "%q#T has virtual functions but non-virtual destructor",
5140 if (warn_overloaded_virtual)
5143 /* Class layout, assignment of virtual table slots, etc., is now
5144 complete. Give the back end a chance to tweak the visibility of
5145 the class or perform any other required target modifications. */
5146 targetm.cxx.adjust_class_at_definition (t);
5148 maybe_suppress_debug_info (t);
5150 dump_class_hierarchy (t);
5152 /* Finish debugging output for this type. */
5153 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5156 /* When T was built up, the member declarations were added in reverse
5157 order. Rearrange them to declaration order. */
5160 unreverse_member_declarations (tree t)
5166 /* The following lists are all in reverse order. Put them in
5167 declaration order now. */
5168 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5169 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5171 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5172 reverse order, so we can't just use nreverse. */
5174 for (x = TYPE_FIELDS (t);
5175 x && TREE_CODE (x) != TYPE_DECL;
5178 next = TREE_CHAIN (x);
5179 TREE_CHAIN (x) = prev;
5184 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5186 TYPE_FIELDS (t) = prev;
5191 finish_struct (tree t, tree attributes)
5193 location_t saved_loc = input_location;
5195 /* Now that we've got all the field declarations, reverse everything
5197 unreverse_member_declarations (t);
5199 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5201 /* Nadger the current location so that diagnostics point to the start of
5202 the struct, not the end. */
5203 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5205 if (processing_template_decl)
5209 finish_struct_methods (t);
5210 TYPE_SIZE (t) = bitsize_zero_node;
5211 TYPE_SIZE_UNIT (t) = size_zero_node;
5213 /* We need to emit an error message if this type was used as a parameter
5214 and it is an abstract type, even if it is a template. We construct
5215 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5216 account and we call complete_vars with this type, which will check
5217 the PARM_DECLS. Note that while the type is being defined,
5218 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5219 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5220 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5221 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5222 if (DECL_PURE_VIRTUAL_P (x))
5223 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5227 finish_struct_1 (t);
5229 input_location = saved_loc;
5231 TYPE_BEING_DEFINED (t) = 0;
5233 if (current_class_type)
5236 error ("trying to finish struct, but kicked out due to previous parse errors");
5238 if (processing_template_decl && at_function_scope_p ())
5239 add_stmt (build_min (TAG_DEFN, t));
5244 /* Return the dynamic type of INSTANCE, if known.
5245 Used to determine whether the virtual function table is needed
5248 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5249 of our knowledge of its type. *NONNULL should be initialized
5250 before this function is called. */
5253 fixed_type_or_null (tree instance, int* nonnull, int* cdtorp)
5255 switch (TREE_CODE (instance))
5258 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5261 return fixed_type_or_null (TREE_OPERAND (instance, 0),
5265 /* This is a call to a constructor, hence it's never zero. */
5266 if (TREE_HAS_CONSTRUCTOR (instance))
5270 return TREE_TYPE (instance);
5275 /* This is a call to a constructor, hence it's never zero. */
5276 if (TREE_HAS_CONSTRUCTOR (instance))
5280 return TREE_TYPE (instance);
5282 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5286 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5287 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5288 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5289 /* Propagate nonnull. */
5290 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5295 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5298 instance = TREE_OPERAND (instance, 0);
5301 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5302 with a real object -- given &p->f, p can still be null. */
5303 tree t = get_base_address (instance);
5304 /* ??? Probably should check DECL_WEAK here. */
5305 if (t && DECL_P (t))
5308 return fixed_type_or_null (instance, nonnull, cdtorp);
5311 /* If this component is really a base class reference, then the field
5312 itself isn't definitive. */
5313 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5314 return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
5315 return fixed_type_or_null (TREE_OPERAND (instance, 1), nonnull, cdtorp);
5319 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5320 && IS_AGGR_TYPE (TREE_TYPE (TREE_TYPE (instance))))
5324 return TREE_TYPE (TREE_TYPE (instance));
5326 /* fall through... */
5330 if (IS_AGGR_TYPE (TREE_TYPE (instance)))
5334 return TREE_TYPE (instance);
5336 else if (instance == current_class_ptr)
5341 /* if we're in a ctor or dtor, we know our type. */
5342 if (DECL_LANG_SPECIFIC (current_function_decl)
5343 && (DECL_CONSTRUCTOR_P (current_function_decl)
5344 || DECL_DESTRUCTOR_P (current_function_decl)))
5348 return TREE_TYPE (TREE_TYPE (instance));
5351 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5353 /* We only need one hash table because it is always left empty. */
5356 ht = htab_create (37,
5361 /* Reference variables should be references to objects. */
5365 /* Enter the INSTANCE in a table to prevent recursion; a
5366 variable's initializer may refer to the variable
5368 if (TREE_CODE (instance) == VAR_DECL
5369 && DECL_INITIAL (instance)
5370 && !htab_find (ht, instance))
5375 slot = htab_find_slot (ht, instance, INSERT);
5377 type = fixed_type_or_null (DECL_INITIAL (instance),
5379 htab_remove_elt (ht, instance);
5391 /* Return nonzero if the dynamic type of INSTANCE is known, and
5392 equivalent to the static type. We also handle the case where
5393 INSTANCE is really a pointer. Return negative if this is a
5394 ctor/dtor. There the dynamic type is known, but this might not be
5395 the most derived base of the original object, and hence virtual
5396 bases may not be layed out according to this type.
5398 Used to determine whether the virtual function table is needed
5401 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5402 of our knowledge of its type. *NONNULL should be initialized
5403 before this function is called. */
5406 resolves_to_fixed_type_p (tree instance, int* nonnull)
5408 tree t = TREE_TYPE (instance);
5411 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5412 if (fixed == NULL_TREE)
5414 if (POINTER_TYPE_P (t))
5416 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5418 return cdtorp ? -1 : 1;
5423 init_class_processing (void)
5425 current_class_depth = 0;
5426 current_class_stack_size = 10;
5428 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5429 local_classes = VEC_alloc (tree, gc, 8);
5430 sizeof_biggest_empty_class = size_zero_node;
5432 ridpointers[(int) RID_PUBLIC] = access_public_node;
5433 ridpointers[(int) RID_PRIVATE] = access_private_node;
5434 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5437 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5440 restore_class_cache (void)
5444 /* We are re-entering the same class we just left, so we don't
5445 have to search the whole inheritance matrix to find all the
5446 decls to bind again. Instead, we install the cached
5447 class_shadowed list and walk through it binding names. */
5448 push_binding_level (previous_class_level);
5449 class_binding_level = previous_class_level;
5450 /* Restore IDENTIFIER_TYPE_VALUE. */
5451 for (type = class_binding_level->type_shadowed;
5453 type = TREE_CHAIN (type))
5454 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5457 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5458 appropriate for TYPE.
5460 So that we may avoid calls to lookup_name, we cache the _TYPE
5461 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5463 For multiple inheritance, we perform a two-pass depth-first search
5464 of the type lattice. */
5467 pushclass (tree type)
5469 class_stack_node_t csn;
5471 type = TYPE_MAIN_VARIANT (type);
5473 /* Make sure there is enough room for the new entry on the stack. */
5474 if (current_class_depth + 1 >= current_class_stack_size)
5476 current_class_stack_size *= 2;
5478 = XRESIZEVEC (struct class_stack_node, current_class_stack,
5479 current_class_stack_size);
5482 /* Insert a new entry on the class stack. */
5483 csn = current_class_stack + current_class_depth;
5484 csn->name = current_class_name;
5485 csn->type = current_class_type;
5486 csn->access = current_access_specifier;
5487 csn->names_used = 0;
5489 current_class_depth++;
5491 /* Now set up the new type. */
5492 current_class_name = TYPE_NAME (type);
5493 if (TREE_CODE (current_class_name) == TYPE_DECL)
5494 current_class_name = DECL_NAME (current_class_name);
5495 current_class_type = type;
5497 /* By default, things in classes are private, while things in
5498 structures or unions are public. */
5499 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5500 ? access_private_node
5501 : access_public_node);
5503 if (previous_class_level
5504 && type != previous_class_level->this_entity
5505 && current_class_depth == 1)
5507 /* Forcibly remove any old class remnants. */
5508 invalidate_class_lookup_cache ();
5511 if (!previous_class_level
5512 || type != previous_class_level->this_entity
5513 || current_class_depth > 1)
5516 restore_class_cache ();
5519 /* When we exit a toplevel class scope, we save its binding level so
5520 that we can restore it quickly. Here, we've entered some other
5521 class, so we must invalidate our cache. */
5524 invalidate_class_lookup_cache (void)
5526 previous_class_level = NULL;
5529 /* Get out of the current class scope. If we were in a class scope
5530 previously, that is the one popped to. */
5537 current_class_depth--;
5538 current_class_name = current_class_stack[current_class_depth].name;
5539 current_class_type = current_class_stack[current_class_depth].type;
5540 current_access_specifier = current_class_stack[current_class_depth].access;
5541 if (current_class_stack[current_class_depth].names_used)
5542 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5545 /* Mark the top of the class stack as hidden. */
5548 push_class_stack (void)
5550 if (current_class_depth)
5551 ++current_class_stack[current_class_depth - 1].hidden;
5554 /* Mark the top of the class stack as un-hidden. */
5557 pop_class_stack (void)
5559 if (current_class_depth)
5560 --current_class_stack[current_class_depth - 1].hidden;
5563 /* Returns 1 if the class type currently being defined is either T or
5564 a nested type of T. */
5567 currently_open_class (tree t)
5571 /* We start looking from 1 because entry 0 is from global scope,
5573 for (i = current_class_depth; i > 0; --i)
5576 if (i == current_class_depth)
5577 c = current_class_type;
5580 if (current_class_stack[i].hidden)
5582 c = current_class_stack[i].type;
5586 if (same_type_p (c, t))
5592 /* If either current_class_type or one of its enclosing classes are derived
5593 from T, return the appropriate type. Used to determine how we found
5594 something via unqualified lookup. */
5597 currently_open_derived_class (tree t)
5601 /* The bases of a dependent type are unknown. */
5602 if (dependent_type_p (t))
5605 if (!current_class_type)
5608 if (DERIVED_FROM_P (t, current_class_type))
5609 return current_class_type;
5611 for (i = current_class_depth - 1; i > 0; --i)
5613 if (current_class_stack[i].hidden)
5615 if (DERIVED_FROM_P (t, current_class_stack[i].type))
5616 return current_class_stack[i].type;
5622 /* When entering a class scope, all enclosing class scopes' names with
5623 static meaning (static variables, static functions, types and
5624 enumerators) have to be visible. This recursive function calls
5625 pushclass for all enclosing class contexts until global or a local
5626 scope is reached. TYPE is the enclosed class. */
5629 push_nested_class (tree type)
5633 /* A namespace might be passed in error cases, like A::B:C. */
5634 if (type == NULL_TREE
5635 || type == error_mark_node
5636 || TREE_CODE (type) == NAMESPACE_DECL
5637 || ! IS_AGGR_TYPE (type)
5638 || TREE_CODE (type) == TEMPLATE_TYPE_PARM
5639 || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
5642 context = DECL_CONTEXT (TYPE_MAIN_DECL (type));
5644 if (context && CLASS_TYPE_P (context))
5645 push_nested_class (context);
5649 /* Undoes a push_nested_class call. */
5652 pop_nested_class (void)
5654 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5657 if (context && CLASS_TYPE_P (context))
5658 pop_nested_class ();
5661 /* Returns the number of extern "LANG" blocks we are nested within. */
5664 current_lang_depth (void)
5666 return VEC_length (tree, current_lang_base);
5669 /* Set global variables CURRENT_LANG_NAME to appropriate value
5670 so that behavior of name-mangling machinery is correct. */
5673 push_lang_context (tree name)
5675 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
5677 if (name == lang_name_cplusplus)
5679 current_lang_name = name;
5681 else if (name == lang_name_java)
5683 current_lang_name = name;
5684 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5685 (See record_builtin_java_type in decl.c.) However, that causes
5686 incorrect debug entries if these types are actually used.
5687 So we re-enable debug output after extern "Java". */
5688 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
5689 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
5690 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
5691 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
5692 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
5693 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
5694 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
5695 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
5697 else if (name == lang_name_c)
5699 current_lang_name = name;
5702 error ("language string %<\"%E\"%> not recognized", name);
5705 /* Get out of the current language scope. */
5708 pop_lang_context (void)
5710 current_lang_name = VEC_pop (tree, current_lang_base);
5713 /* Type instantiation routines. */
5715 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
5716 matches the TARGET_TYPE. If there is no satisfactory match, return
5717 error_mark_node, and issue an error & warning messages under
5718 control of FLAGS. Permit pointers to member function if FLAGS
5719 permits. If TEMPLATE_ONLY, the name of the overloaded function was
5720 a template-id, and EXPLICIT_TARGS are the explicitly provided
5721 template arguments. If OVERLOAD is for one or more member
5722 functions, then ACCESS_PATH is the base path used to reference
5723 those member functions. */
5726 resolve_address_of_overloaded_function (tree target_type,
5728 tsubst_flags_t flags,
5730 tree explicit_targs,
5733 /* Here's what the standard says:
5737 If the name is a function template, template argument deduction
5738 is done, and if the argument deduction succeeds, the deduced
5739 arguments are used to generate a single template function, which
5740 is added to the set of overloaded functions considered.
5742 Non-member functions and static member functions match targets of
5743 type "pointer-to-function" or "reference-to-function." Nonstatic
5744 member functions match targets of type "pointer-to-member
5745 function;" the function type of the pointer to member is used to
5746 select the member function from the set of overloaded member
5747 functions. If a nonstatic member function is selected, the
5748 reference to the overloaded function name is required to have the
5749 form of a pointer to member as described in 5.3.1.
5751 If more than one function is selected, any template functions in
5752 the set are eliminated if the set also contains a non-template
5753 function, and any given template function is eliminated if the
5754 set contains a second template function that is more specialized
5755 than the first according to the partial ordering rules 14.5.5.2.
5756 After such eliminations, if any, there shall remain exactly one
5757 selected function. */
5760 int is_reference = 0;
5761 /* We store the matches in a TREE_LIST rooted here. The functions
5762 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
5763 interoperability with most_specialized_instantiation. */
5764 tree matches = NULL_TREE;
5767 /* By the time we get here, we should be seeing only real
5768 pointer-to-member types, not the internal POINTER_TYPE to
5769 METHOD_TYPE representation. */
5770 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
5771 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
5773 gcc_assert (is_overloaded_fn (overload));
5775 /* Check that the TARGET_TYPE is reasonable. */
5776 if (TYPE_PTRFN_P (target_type))
5778 else if (TYPE_PTRMEMFUNC_P (target_type))
5779 /* This is OK, too. */
5781 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
5783 /* This is OK, too. This comes from a conversion to reference
5785 target_type = build_reference_type (target_type);
5790 if (flags & tf_error)
5791 error ("cannot resolve overloaded function %qD based on"
5792 " conversion to type %qT",
5793 DECL_NAME (OVL_FUNCTION (overload)), target_type);
5794 return error_mark_node;
5797 /* If we can find a non-template function that matches, we can just
5798 use it. There's no point in generating template instantiations
5799 if we're just going to throw them out anyhow. But, of course, we
5800 can only do this when we don't *need* a template function. */
5805 for (fns = overload; fns; fns = OVL_NEXT (fns))
5807 tree fn = OVL_CURRENT (fns);
5810 if (TREE_CODE (fn) == TEMPLATE_DECL)
5811 /* We're not looking for templates just yet. */
5814 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5816 /* We're looking for a non-static member, and this isn't
5817 one, or vice versa. */
5820 /* Ignore functions which haven't been explicitly
5822 if (DECL_ANTICIPATED (fn))
5825 /* See if there's a match. */
5826 fntype = TREE_TYPE (fn);
5828 fntype = build_ptrmemfunc_type (build_pointer_type (fntype));
5829 else if (!is_reference)
5830 fntype = build_pointer_type (fntype);
5832 if (can_convert_arg (target_type, fntype, fn, LOOKUP_NORMAL))
5833 matches = tree_cons (fn, NULL_TREE, matches);
5837 /* Now, if we've already got a match (or matches), there's no need
5838 to proceed to the template functions. But, if we don't have a
5839 match we need to look at them, too. */
5842 tree target_fn_type;
5843 tree target_arg_types;
5844 tree target_ret_type;
5849 = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (target_type));
5851 target_fn_type = TREE_TYPE (target_type);
5852 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
5853 target_ret_type = TREE_TYPE (target_fn_type);
5855 /* Never do unification on the 'this' parameter. */
5856 if (TREE_CODE (target_fn_type) == METHOD_TYPE)
5857 target_arg_types = TREE_CHAIN (target_arg_types);
5859 for (fns = overload; fns; fns = OVL_NEXT (fns))
5861 tree fn = OVL_CURRENT (fns);
5863 tree instantiation_type;
5866 if (TREE_CODE (fn) != TEMPLATE_DECL)
5867 /* We're only looking for templates. */
5870 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5872 /* We're not looking for a non-static member, and this is
5873 one, or vice versa. */
5876 /* Try to do argument deduction. */
5877 targs = make_tree_vec (DECL_NTPARMS (fn));
5878 if (fn_type_unification (fn, explicit_targs, targs,
5879 target_arg_types, target_ret_type,
5880 DEDUCE_EXACT, LOOKUP_NORMAL))
5881 /* Argument deduction failed. */
5884 /* Instantiate the template. */
5885 instantiation = instantiate_template (fn, targs, flags);
5886 if (instantiation == error_mark_node)
5887 /* Instantiation failed. */
5890 /* See if there's a match. */
5891 instantiation_type = TREE_TYPE (instantiation);
5893 instantiation_type =
5894 build_ptrmemfunc_type (build_pointer_type (instantiation_type));
5895 else if (!is_reference)
5896 instantiation_type = build_pointer_type (instantiation_type);
5897 if (can_convert_arg (target_type, instantiation_type, instantiation,
5899 matches = tree_cons (instantiation, fn, matches);
5902 /* Now, remove all but the most specialized of the matches. */
5905 tree match = most_specialized_instantiation (matches);
5907 if (match != error_mark_node)
5908 matches = tree_cons (TREE_PURPOSE (match),
5914 /* Now we should have exactly one function in MATCHES. */
5915 if (matches == NULL_TREE)
5917 /* There were *no* matches. */
5918 if (flags & tf_error)
5920 error ("no matches converting function %qD to type %q#T",
5921 DECL_NAME (OVL_FUNCTION (overload)),
5924 /* print_candidates expects a chain with the functions in
5925 TREE_VALUE slots, so we cons one up here (we're losing anyway,
5926 so why be clever?). */
5927 for (; overload; overload = OVL_NEXT (overload))
5928 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
5931 print_candidates (matches);
5933 return error_mark_node;
5935 else if (TREE_CHAIN (matches))
5937 /* There were too many matches. */
5939 if (flags & tf_error)
5943 error ("converting overloaded function %qD to type %q#T is ambiguous",
5944 DECL_NAME (OVL_FUNCTION (overload)),
5947 /* Since print_candidates expects the functions in the
5948 TREE_VALUE slot, we flip them here. */
5949 for (match = matches; match; match = TREE_CHAIN (match))
5950 TREE_VALUE (match) = TREE_PURPOSE (match);
5952 print_candidates (matches);
5955 return error_mark_node;
5958 /* Good, exactly one match. Now, convert it to the correct type. */
5959 fn = TREE_PURPOSE (matches);
5961 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
5962 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
5964 static int explained;
5966 if (!(flags & tf_error))
5967 return error_mark_node;
5969 pedwarn ("assuming pointer to member %qD", fn);
5972 pedwarn ("(a pointer to member can only be formed with %<&%E%>)", fn);
5977 /* If we're doing overload resolution purely for the purpose of
5978 determining conversion sequences, we should not consider the
5979 function used. If this conversion sequence is selected, the
5980 function will be marked as used at this point. */
5981 if (!(flags & tf_conv))
5984 /* We could not check access when this expression was originally
5985 created since we did not know at that time to which function
5986 the expression referred. */
5987 if (DECL_FUNCTION_MEMBER_P (fn))
5989 gcc_assert (access_path);
5990 perform_or_defer_access_check (access_path, fn, fn);
5994 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
5995 return build_unary_op (ADDR_EXPR, fn, 0);
5998 /* The target must be a REFERENCE_TYPE. Above, build_unary_op
5999 will mark the function as addressed, but here we must do it
6001 cxx_mark_addressable (fn);
6007 /* This function will instantiate the type of the expression given in
6008 RHS to match the type of LHSTYPE. If errors exist, then return
6009 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6010 we complain on errors. If we are not complaining, never modify rhs,
6011 as overload resolution wants to try many possible instantiations, in
6012 the hope that at least one will work.
6014 For non-recursive calls, LHSTYPE should be a function, pointer to
6015 function, or a pointer to member function. */
6018 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6020 tsubst_flags_t flags_in = flags;
6021 tree access_path = NULL_TREE;
6023 flags &= ~tf_ptrmem_ok;
6025 if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
6027 if (flags & tf_error)
6028 error ("not enough type information");
6029 return error_mark_node;
6032 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6034 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6036 if (flag_ms_extensions
6037 && TYPE_PTRMEMFUNC_P (lhstype)
6038 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6039 /* Microsoft allows `A::f' to be resolved to a
6040 pointer-to-member. */
6044 if (flags & tf_error)
6045 error ("argument of type %qT does not match %qT",
6046 TREE_TYPE (rhs), lhstype);
6047 return error_mark_node;
6051 if (TREE_CODE (rhs) == BASELINK)
6053 access_path = BASELINK_ACCESS_BINFO (rhs);
6054 rhs = BASELINK_FUNCTIONS (rhs);
6057 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6058 deduce any type information. */
6059 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6061 if (flags & tf_error)
6062 error ("not enough type information");
6063 return error_mark_node;
6066 /* There only a few kinds of expressions that may have a type
6067 dependent on overload resolution. */
6068 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6069 || TREE_CODE (rhs) == COMPONENT_REF
6070 || TREE_CODE (rhs) == COMPOUND_EXPR
6071 || really_overloaded_fn (rhs));
6073 /* We don't overwrite rhs if it is an overloaded function.
6074 Copying it would destroy the tree link. */
6075 if (TREE_CODE (rhs) != OVERLOAD)
6076 rhs = copy_node (rhs);
6078 /* This should really only be used when attempting to distinguish
6079 what sort of a pointer to function we have. For now, any
6080 arithmetic operation which is not supported on pointers
6081 is rejected as an error. */
6083 switch (TREE_CODE (rhs))
6087 tree member = TREE_OPERAND (rhs, 1);
6089 member = instantiate_type (lhstype, member, flags);
6090 if (member != error_mark_node
6091 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6092 /* Do not lose object's side effects. */
6093 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6094 TREE_OPERAND (rhs, 0), member);
6099 rhs = TREE_OPERAND (rhs, 1);
6100 if (BASELINK_P (rhs))
6101 return instantiate_type (lhstype, rhs, flags_in);
6103 /* This can happen if we are forming a pointer-to-member for a
6105 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6109 case TEMPLATE_ID_EXPR:
6111 tree fns = TREE_OPERAND (rhs, 0);
6112 tree args = TREE_OPERAND (rhs, 1);
6115 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6116 /*template_only=*/true,
6123 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6124 /*template_only=*/false,
6125 /*explicit_targs=*/NULL_TREE,
6129 TREE_OPERAND (rhs, 0)
6130 = instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6131 if (TREE_OPERAND (rhs, 0) == error_mark_node)
6132 return error_mark_node;
6133 TREE_OPERAND (rhs, 1)
6134 = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags);
6135 if (TREE_OPERAND (rhs, 1) == error_mark_node)
6136 return error_mark_node;
6138 TREE_TYPE (rhs) = lhstype;
6143 if (PTRMEM_OK_P (rhs))
6144 flags |= tf_ptrmem_ok;
6146 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6150 return error_mark_node;
6155 return error_mark_node;
6158 /* Return the name of the virtual function pointer field
6159 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6160 this may have to look back through base types to find the
6161 ultimate field name. (For single inheritance, these could
6162 all be the same name. Who knows for multiple inheritance). */
6165 get_vfield_name (tree type)
6167 tree binfo, base_binfo;
6170 for (binfo = TYPE_BINFO (type);
6171 BINFO_N_BASE_BINFOS (binfo);
6174 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6176 if (BINFO_VIRTUAL_P (base_binfo)
6177 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6181 type = BINFO_TYPE (binfo);
6182 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6183 + TYPE_NAME_LENGTH (type) + 2);
6184 sprintf (buf, VFIELD_NAME_FORMAT,
6185 IDENTIFIER_POINTER (constructor_name (type)));
6186 return get_identifier (buf);
6190 print_class_statistics (void)
6192 #ifdef GATHER_STATISTICS
6193 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6194 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6197 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6198 n_vtables, n_vtable_searches);
6199 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6200 n_vtable_entries, n_vtable_elems);
6205 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6206 according to [class]:
6207 The class-name is also inserted
6208 into the scope of the class itself. For purposes of access checking,
6209 the inserted class name is treated as if it were a public member name. */
6212 build_self_reference (void)
6214 tree name = constructor_name (current_class_type);
6215 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6218 DECL_NONLOCAL (value) = 1;
6219 DECL_CONTEXT (value) = current_class_type;
6220 DECL_ARTIFICIAL (value) = 1;
6221 SET_DECL_SELF_REFERENCE_P (value);
6223 if (processing_template_decl)
6224 value = push_template_decl (value);
6226 saved_cas = current_access_specifier;
6227 current_access_specifier = access_public_node;
6228 finish_member_declaration (value);
6229 current_access_specifier = saved_cas;
6232 /* Returns 1 if TYPE contains only padding bytes. */
6235 is_empty_class (tree type)
6237 if (type == error_mark_node)
6240 if (! IS_AGGR_TYPE (type))
6243 /* In G++ 3.2, whether or not a class was empty was determined by
6244 looking at its size. */
6245 if (abi_version_at_least (2))
6246 return CLASSTYPE_EMPTY_P (type);
6248 return integer_zerop (CLASSTYPE_SIZE (type));
6251 /* Returns true if TYPE contains an empty class. */
6254 contains_empty_class_p (tree type)
6256 if (is_empty_class (type))
6258 if (CLASS_TYPE_P (type))
6265 for (binfo = TYPE_BINFO (type), i = 0;
6266 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6267 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6269 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6270 if (TREE_CODE (field) == FIELD_DECL
6271 && !DECL_ARTIFICIAL (field)
6272 && is_empty_class (TREE_TYPE (field)))
6275 else if (TREE_CODE (type) == ARRAY_TYPE)
6276 return contains_empty_class_p (TREE_TYPE (type));
6280 /* Note that NAME was looked up while the current class was being
6281 defined and that the result of that lookup was DECL. */
6284 maybe_note_name_used_in_class (tree name, tree decl)
6286 splay_tree names_used;
6288 /* If we're not defining a class, there's nothing to do. */
6289 if (!(innermost_scope_kind() == sk_class
6290 && TYPE_BEING_DEFINED (current_class_type)))
6293 /* If there's already a binding for this NAME, then we don't have
6294 anything to worry about. */
6295 if (lookup_member (current_class_type, name,
6296 /*protect=*/0, /*want_type=*/false))
6299 if (!current_class_stack[current_class_depth - 1].names_used)
6300 current_class_stack[current_class_depth - 1].names_used
6301 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6302 names_used = current_class_stack[current_class_depth - 1].names_used;
6304 splay_tree_insert (names_used,
6305 (splay_tree_key) name,
6306 (splay_tree_value) decl);
6309 /* Note that NAME was declared (as DECL) in the current class. Check
6310 to see that the declaration is valid. */
6313 note_name_declared_in_class (tree name, tree decl)
6315 splay_tree names_used;
6318 /* Look to see if we ever used this name. */
6320 = current_class_stack[current_class_depth - 1].names_used;
6324 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6327 /* [basic.scope.class]
6329 A name N used in a class S shall refer to the same declaration
6330 in its context and when re-evaluated in the completed scope of
6332 error ("declaration of %q#D", decl);
6333 error ("changes meaning of %qD from %q+#D",
6334 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6338 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6339 Secondary vtables are merged with primary vtables; this function
6340 will return the VAR_DECL for the primary vtable. */
6343 get_vtbl_decl_for_binfo (tree binfo)
6347 decl = BINFO_VTABLE (binfo);
6348 if (decl && TREE_CODE (decl) == PLUS_EXPR)
6350 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6351 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6354 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6359 /* Returns the binfo for the primary base of BINFO. If the resulting
6360 BINFO is a virtual base, and it is inherited elsewhere in the
6361 hierarchy, then the returned binfo might not be the primary base of
6362 BINFO in the complete object. Check BINFO_PRIMARY_P or
6363 BINFO_LOST_PRIMARY_P to be sure. */
6366 get_primary_binfo (tree binfo)
6370 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6374 return copied_binfo (primary_base, binfo);
6377 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6380 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6383 fprintf (stream, "%*s", indent, "");
6387 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6388 INDENT should be zero when called from the top level; it is
6389 incremented recursively. IGO indicates the next expected BINFO in
6390 inheritance graph ordering. */
6393 dump_class_hierarchy_r (FILE *stream,
6403 indented = maybe_indent_hierarchy (stream, indent, 0);
6404 fprintf (stream, "%s (0x%lx) ",
6405 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6406 (unsigned long) binfo);
6409 fprintf (stream, "alternative-path\n");
6412 igo = TREE_CHAIN (binfo);
6414 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6415 tree_low_cst (BINFO_OFFSET (binfo), 0));
6416 if (is_empty_class (BINFO_TYPE (binfo)))
6417 fprintf (stream, " empty");
6418 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6419 fprintf (stream, " nearly-empty");
6420 if (BINFO_VIRTUAL_P (binfo))
6421 fprintf (stream, " virtual");
6422 fprintf (stream, "\n");
6425 if (BINFO_PRIMARY_P (binfo))
6427 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6428 fprintf (stream, " primary-for %s (0x%lx)",
6429 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6430 TFF_PLAIN_IDENTIFIER),
6431 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6433 if (BINFO_LOST_PRIMARY_P (binfo))
6435 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6436 fprintf (stream, " lost-primary");
6439 fprintf (stream, "\n");
6441 if (!(flags & TDF_SLIM))
6445 if (BINFO_SUBVTT_INDEX (binfo))
6447 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6448 fprintf (stream, " subvttidx=%s",
6449 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6450 TFF_PLAIN_IDENTIFIER));
6452 if (BINFO_VPTR_INDEX (binfo))
6454 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6455 fprintf (stream, " vptridx=%s",
6456 expr_as_string (BINFO_VPTR_INDEX (binfo),
6457 TFF_PLAIN_IDENTIFIER));
6459 if (BINFO_VPTR_FIELD (binfo))
6461 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6462 fprintf (stream, " vbaseoffset=%s",
6463 expr_as_string (BINFO_VPTR_FIELD (binfo),
6464 TFF_PLAIN_IDENTIFIER));
6466 if (BINFO_VTABLE (binfo))
6468 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6469 fprintf (stream, " vptr=%s",
6470 expr_as_string (BINFO_VTABLE (binfo),
6471 TFF_PLAIN_IDENTIFIER));
6475 fprintf (stream, "\n");
6478 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6479 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6484 /* Dump the BINFO hierarchy for T. */
6487 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6489 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6490 fprintf (stream, " size=%lu align=%lu\n",
6491 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6492 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6493 fprintf (stream, " base size=%lu base align=%lu\n",
6494 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6496 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6498 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6499 fprintf (stream, "\n");
6502 /* Debug interface to hierarchy dumping. */
6505 debug_class (tree t)
6507 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6511 dump_class_hierarchy (tree t)
6514 FILE *stream = dump_begin (TDI_class, &flags);
6518 dump_class_hierarchy_1 (stream, flags, t);
6519 dump_end (TDI_class, stream);
6524 dump_array (FILE * stream, tree decl)
6527 unsigned HOST_WIDE_INT ix;
6529 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6531 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6533 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6534 fprintf (stream, " %s entries",
6535 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6536 TFF_PLAIN_IDENTIFIER));
6537 fprintf (stream, "\n");
6539 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
6541 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
6542 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
6546 dump_vtable (tree t, tree binfo, tree vtable)
6549 FILE *stream = dump_begin (TDI_class, &flags);
6554 if (!(flags & TDF_SLIM))
6556 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6558 fprintf (stream, "%s for %s",
6559 ctor_vtbl_p ? "Construction vtable" : "Vtable",
6560 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6563 if (!BINFO_VIRTUAL_P (binfo))
6564 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6565 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6567 fprintf (stream, "\n");
6568 dump_array (stream, vtable);
6569 fprintf (stream, "\n");
6572 dump_end (TDI_class, stream);
6576 dump_vtt (tree t, tree vtt)
6579 FILE *stream = dump_begin (TDI_class, &flags);
6584 if (!(flags & TDF_SLIM))
6586 fprintf (stream, "VTT for %s\n",
6587 type_as_string (t, TFF_PLAIN_IDENTIFIER));
6588 dump_array (stream, vtt);
6589 fprintf (stream, "\n");
6592 dump_end (TDI_class, stream);
6595 /* Dump a function or thunk and its thunkees. */
6598 dump_thunk (FILE *stream, int indent, tree thunk)
6600 static const char spaces[] = " ";
6601 tree name = DECL_NAME (thunk);
6604 fprintf (stream, "%.*s%p %s %s", indent, spaces,
6606 !DECL_THUNK_P (thunk) ? "function"
6607 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6608 name ? IDENTIFIER_POINTER (name) : "<unset>");
6609 if (DECL_THUNK_P (thunk))
6611 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6612 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6614 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6615 if (!virtual_adjust)
6617 else if (DECL_THIS_THUNK_P (thunk))
6618 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
6619 tree_low_cst (virtual_adjust, 0));
6621 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6622 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6623 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6624 if (THUNK_ALIAS (thunk))
6625 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6627 fprintf (stream, "\n");
6628 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6629 dump_thunk (stream, indent + 2, thunks);
6632 /* Dump the thunks for FN. */
6635 debug_thunks (tree fn)
6637 dump_thunk (stderr, 0, fn);
6640 /* Virtual function table initialization. */
6642 /* Create all the necessary vtables for T and its base classes. */
6645 finish_vtbls (tree t)
6650 /* We lay out the primary and secondary vtables in one contiguous
6651 vtable. The primary vtable is first, followed by the non-virtual
6652 secondary vtables in inheritance graph order. */
6653 list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6654 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6655 TYPE_BINFO (t), t, list);
6657 /* Then come the virtual bases, also in inheritance graph order. */
6658 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6660 if (!BINFO_VIRTUAL_P (vbase))
6662 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6665 if (BINFO_VTABLE (TYPE_BINFO (t)))
6666 initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
6669 /* Initialize the vtable for BINFO with the INITS. */
6672 initialize_vtable (tree binfo, tree inits)
6676 layout_vtable_decl (binfo, list_length (inits));
6677 decl = get_vtbl_decl_for_binfo (binfo);
6678 initialize_artificial_var (decl, inits);
6679 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
6682 /* Build the VTT (virtual table table) for T.
6683 A class requires a VTT if it has virtual bases.
6686 1 - primary virtual pointer for complete object T
6687 2 - secondary VTTs for each direct non-virtual base of T which requires a
6689 3 - secondary virtual pointers for each direct or indirect base of T which
6690 has virtual bases or is reachable via a virtual path from T.
6691 4 - secondary VTTs for each direct or indirect virtual base of T.
6693 Secondary VTTs look like complete object VTTs without part 4. */
6703 /* Build up the initializers for the VTT. */
6705 index = size_zero_node;
6706 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
6708 /* If we didn't need a VTT, we're done. */
6712 /* Figure out the type of the VTT. */
6713 type = build_index_type (size_int (list_length (inits) - 1));
6714 type = build_cplus_array_type (const_ptr_type_node, type);
6716 /* Now, build the VTT object itself. */
6717 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
6718 initialize_artificial_var (vtt, inits);
6719 /* Add the VTT to the vtables list. */
6720 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
6721 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
6726 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
6727 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
6728 and CHAIN the vtable pointer for this binfo after construction is
6729 complete. VALUE can also be another BINFO, in which case we recurse. */
6732 binfo_ctor_vtable (tree binfo)
6738 vt = BINFO_VTABLE (binfo);
6739 if (TREE_CODE (vt) == TREE_LIST)
6740 vt = TREE_VALUE (vt);
6741 if (TREE_CODE (vt) == TREE_BINFO)
6750 /* Data for secondary VTT initialization. */
6751 typedef struct secondary_vptr_vtt_init_data_s
6753 /* Is this the primary VTT? */
6756 /* Current index into the VTT. */
6759 /* TREE_LIST of initializers built up. */
6762 /* The type being constructed by this secondary VTT. */
6763 tree type_being_constructed;
6764 } secondary_vptr_vtt_init_data;
6766 /* Recursively build the VTT-initializer for BINFO (which is in the
6767 hierarchy dominated by T). INITS points to the end of the initializer
6768 list to date. INDEX is the VTT index where the next element will be
6769 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
6770 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
6771 for virtual bases of T. When it is not so, we build the constructor
6772 vtables for the BINFO-in-T variant. */
6775 build_vtt_inits (tree binfo, tree t, tree *inits, tree *index)
6780 tree secondary_vptrs;
6781 secondary_vptr_vtt_init_data data;
6782 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
6784 /* We only need VTTs for subobjects with virtual bases. */
6785 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
6788 /* We need to use a construction vtable if this is not the primary
6792 build_ctor_vtbl_group (binfo, t);
6794 /* Record the offset in the VTT where this sub-VTT can be found. */
6795 BINFO_SUBVTT_INDEX (binfo) = *index;
6798 /* Add the address of the primary vtable for the complete object. */
6799 init = binfo_ctor_vtable (binfo);
6800 *inits = build_tree_list (NULL_TREE, init);
6801 inits = &TREE_CHAIN (*inits);
6804 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6805 BINFO_VPTR_INDEX (binfo) = *index;
6807 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
6809 /* Recursively add the secondary VTTs for non-virtual bases. */
6810 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
6811 if (!BINFO_VIRTUAL_P (b))
6812 inits = build_vtt_inits (b, t, inits, index);
6814 /* Add secondary virtual pointers for all subobjects of BINFO with
6815 either virtual bases or reachable along a virtual path, except
6816 subobjects that are non-virtual primary bases. */
6817 data.top_level_p = top_level_p;
6818 data.index = *index;
6820 data.type_being_constructed = BINFO_TYPE (binfo);
6822 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
6824 *index = data.index;
6826 /* The secondary vptrs come back in reverse order. After we reverse
6827 them, and add the INITS, the last init will be the first element
6829 secondary_vptrs = data.inits;
6830 if (secondary_vptrs)
6832 *inits = nreverse (secondary_vptrs);
6833 inits = &TREE_CHAIN (secondary_vptrs);
6834 gcc_assert (*inits == NULL_TREE);
6838 /* Add the secondary VTTs for virtual bases in inheritance graph
6840 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
6842 if (!BINFO_VIRTUAL_P (b))
6845 inits = build_vtt_inits (b, t, inits, index);
6848 /* Remove the ctor vtables we created. */
6849 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
6854 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
6855 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
6858 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
6860 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
6862 /* We don't care about bases that don't have vtables. */
6863 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
6864 return dfs_skip_bases;
6866 /* We're only interested in proper subobjects of the type being
6868 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
6871 /* We're only interested in bases with virtual bases or reachable
6872 via a virtual path from the type being constructed. */
6873 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
6874 || binfo_via_virtual (binfo, data->type_being_constructed)))
6875 return dfs_skip_bases;
6877 /* We're not interested in non-virtual primary bases. */
6878 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
6881 /* Record the index where this secondary vptr can be found. */
6882 if (data->top_level_p)
6884 gcc_assert (!BINFO_VPTR_INDEX (binfo));
6885 BINFO_VPTR_INDEX (binfo) = data->index;
6887 if (BINFO_VIRTUAL_P (binfo))
6889 /* It's a primary virtual base, and this is not a
6890 construction vtable. Find the base this is primary of in
6891 the inheritance graph, and use that base's vtable
6893 while (BINFO_PRIMARY_P (binfo))
6894 binfo = BINFO_INHERITANCE_CHAIN (binfo);
6898 /* Add the initializer for the secondary vptr itself. */
6899 data->inits = tree_cons (NULL_TREE, binfo_ctor_vtable (binfo), data->inits);
6901 /* Advance the vtt index. */
6902 data->index = size_binop (PLUS_EXPR, data->index,
6903 TYPE_SIZE_UNIT (ptr_type_node));
6908 /* Called from build_vtt_inits via dfs_walk. After building
6909 constructor vtables and generating the sub-vtt from them, we need
6910 to restore the BINFO_VTABLES that were scribbled on. DATA is the
6911 binfo of the base whose sub vtt was generated. */
6914 dfs_fixup_binfo_vtbls (tree binfo, void* data)
6916 tree vtable = BINFO_VTABLE (binfo);
6918 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
6919 /* If this class has no vtable, none of its bases do. */
6920 return dfs_skip_bases;
6923 /* This might be a primary base, so have no vtable in this
6927 /* If we scribbled the construction vtable vptr into BINFO, clear it
6929 if (TREE_CODE (vtable) == TREE_LIST
6930 && (TREE_PURPOSE (vtable) == (tree) data))
6931 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
6936 /* Build the construction vtable group for BINFO which is in the
6937 hierarchy dominated by T. */
6940 build_ctor_vtbl_group (tree binfo, tree t)
6949 /* See if we've already created this construction vtable group. */
6950 id = mangle_ctor_vtbl_for_type (t, binfo);
6951 if (IDENTIFIER_GLOBAL_VALUE (id))
6954 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
6955 /* Build a version of VTBL (with the wrong type) for use in
6956 constructing the addresses of secondary vtables in the
6957 construction vtable group. */
6958 vtbl = build_vtable (t, id, ptr_type_node);
6959 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
6960 list = build_tree_list (vtbl, NULL_TREE);
6961 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
6964 /* Add the vtables for each of our virtual bases using the vbase in T
6966 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
6968 vbase = TREE_CHAIN (vbase))
6972 if (!BINFO_VIRTUAL_P (vbase))
6974 b = copied_binfo (vbase, binfo);
6976 accumulate_vtbl_inits (b, vbase, binfo, t, list);
6978 inits = TREE_VALUE (list);
6980 /* Figure out the type of the construction vtable. */
6981 type = build_index_type (size_int (list_length (inits) - 1));
6982 type = build_cplus_array_type (vtable_entry_type, type);
6983 TREE_TYPE (vtbl) = type;
6985 /* Initialize the construction vtable. */
6986 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
6987 initialize_artificial_var (vtbl, inits);
6988 dump_vtable (t, binfo, vtbl);
6991 /* Add the vtbl initializers for BINFO (and its bases other than
6992 non-virtual primaries) to the list of INITS. BINFO is in the
6993 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
6994 the constructor the vtbl inits should be accumulated for. (If this
6995 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
6996 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
6997 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
6998 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
6999 but are not necessarily the same in terms of layout. */
7002 accumulate_vtbl_inits (tree binfo,
7010 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7012 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7014 /* If it doesn't have a vptr, we don't do anything. */
7015 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7018 /* If we're building a construction vtable, we're not interested in
7019 subobjects that don't require construction vtables. */
7021 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7022 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7025 /* Build the initializers for the BINFO-in-T vtable. */
7027 = chainon (TREE_VALUE (inits),
7028 dfs_accumulate_vtbl_inits (binfo, orig_binfo,
7029 rtti_binfo, t, inits));
7031 /* Walk the BINFO and its bases. We walk in preorder so that as we
7032 initialize each vtable we can figure out at what offset the
7033 secondary vtable lies from the primary vtable. We can't use
7034 dfs_walk here because we need to iterate through bases of BINFO
7035 and RTTI_BINFO simultaneously. */
7036 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7038 /* Skip virtual bases. */
7039 if (BINFO_VIRTUAL_P (base_binfo))
7041 accumulate_vtbl_inits (base_binfo,
7042 BINFO_BASE_BINFO (orig_binfo, i),
7048 /* Called from accumulate_vtbl_inits. Returns the initializers for
7049 the BINFO vtable. */
7052 dfs_accumulate_vtbl_inits (tree binfo,
7058 tree inits = NULL_TREE;
7059 tree vtbl = NULL_TREE;
7060 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7063 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7065 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7066 primary virtual base. If it is not the same primary in
7067 the hierarchy of T, we'll need to generate a ctor vtable
7068 for it, to place at its location in T. If it is the same
7069 primary, we still need a VTT entry for the vtable, but it
7070 should point to the ctor vtable for the base it is a
7071 primary for within the sub-hierarchy of RTTI_BINFO.
7073 There are three possible cases:
7075 1) We are in the same place.
7076 2) We are a primary base within a lost primary virtual base of
7078 3) We are primary to something not a base of RTTI_BINFO. */
7081 tree last = NULL_TREE;
7083 /* First, look through the bases we are primary to for RTTI_BINFO
7084 or a virtual base. */
7086 while (BINFO_PRIMARY_P (b))
7088 b = BINFO_INHERITANCE_CHAIN (b);
7090 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7093 /* If we run out of primary links, keep looking down our
7094 inheritance chain; we might be an indirect primary. */
7095 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7096 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7100 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7101 base B and it is a base of RTTI_BINFO, this is case 2. In
7102 either case, we share our vtable with LAST, i.e. the
7103 derived-most base within B of which we are a primary. */
7105 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7106 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7107 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7108 binfo_ctor_vtable after everything's been set up. */
7111 /* Otherwise, this is case 3 and we get our own. */
7113 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7121 /* Compute the initializer for this vtable. */
7122 inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7125 /* Figure out the position to which the VPTR should point. */
7126 vtbl = TREE_PURPOSE (l);
7127 vtbl = build_address (vtbl);
7128 /* ??? We should call fold_convert to convert the address to
7129 vtbl_ptr_type_node, which is the type of elements in the
7130 vtable. However, the resulting NOP_EXPRs confuse other parts
7131 of the C++ front end. */
7132 gcc_assert (TREE_CODE (vtbl) == ADDR_EXPR);
7133 TREE_TYPE (vtbl) = vtbl_ptr_type_node;
7134 index = size_binop (PLUS_EXPR,
7135 size_int (non_fn_entries),
7136 size_int (list_length (TREE_VALUE (l))));
7137 index = size_binop (MULT_EXPR,
7138 TYPE_SIZE_UNIT (vtable_entry_type),
7140 vtbl = build2 (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7144 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7145 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7146 straighten this out. */
7147 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7148 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7151 /* For an ordinary vtable, set BINFO_VTABLE. */
7152 BINFO_VTABLE (binfo) = vtbl;
7157 static GTY(()) tree abort_fndecl_addr;
7159 /* Construct the initializer for BINFO's virtual function table. BINFO
7160 is part of the hierarchy dominated by T. If we're building a
7161 construction vtable, the ORIG_BINFO is the binfo we should use to
7162 find the actual function pointers to put in the vtable - but they
7163 can be overridden on the path to most-derived in the graph that
7164 ORIG_BINFO belongs. Otherwise,
7165 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7166 BINFO that should be indicated by the RTTI information in the
7167 vtable; it will be a base class of T, rather than T itself, if we
7168 are building a construction vtable.
7170 The value returned is a TREE_LIST suitable for wrapping in a
7171 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7172 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7173 number of non-function entries in the vtable.
7175 It might seem that this function should never be called with a
7176 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7177 base is always subsumed by a derived class vtable. However, when
7178 we are building construction vtables, we do build vtables for
7179 primary bases; we need these while the primary base is being
7183 build_vtbl_initializer (tree binfo,
7187 int* non_fn_entries_p)
7194 VEC(tree,gc) *vbases;
7196 /* Initialize VID. */
7197 memset (&vid, 0, sizeof (vid));
7200 vid.rtti_binfo = rtti_binfo;
7201 vid.last_init = &vid.inits;
7202 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7203 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7204 vid.generate_vcall_entries = true;
7205 /* The first vbase or vcall offset is at index -3 in the vtable. */
7206 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7208 /* Add entries to the vtable for RTTI. */
7209 build_rtti_vtbl_entries (binfo, &vid);
7211 /* Create an array for keeping track of the functions we've
7212 processed. When we see multiple functions with the same
7213 signature, we share the vcall offsets. */
7214 vid.fns = VEC_alloc (tree, gc, 32);
7215 /* Add the vcall and vbase offset entries. */
7216 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7218 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7219 build_vbase_offset_vtbl_entries. */
7220 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7221 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7222 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7224 /* If the target requires padding between data entries, add that now. */
7225 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7229 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7234 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7235 add = tree_cons (NULL_TREE,
7236 build1 (NOP_EXPR, vtable_entry_type,
7243 if (non_fn_entries_p)
7244 *non_fn_entries_p = list_length (vid.inits);
7246 /* Go through all the ordinary virtual functions, building up
7248 vfun_inits = NULL_TREE;
7249 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7253 tree fn, fn_original;
7254 tree init = NULL_TREE;
7258 if (DECL_THUNK_P (fn))
7260 if (!DECL_NAME (fn))
7262 if (THUNK_ALIAS (fn))
7264 fn = THUNK_ALIAS (fn);
7267 fn_original = THUNK_TARGET (fn);
7270 /* If the only definition of this function signature along our
7271 primary base chain is from a lost primary, this vtable slot will
7272 never be used, so just zero it out. This is important to avoid
7273 requiring extra thunks which cannot be generated with the function.
7275 We first check this in update_vtable_entry_for_fn, so we handle
7276 restored primary bases properly; we also need to do it here so we
7277 zero out unused slots in ctor vtables, rather than filling themff
7278 with erroneous values (though harmless, apart from relocation
7280 for (b = binfo; ; b = get_primary_binfo (b))
7282 /* We found a defn before a lost primary; go ahead as normal. */
7283 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7286 /* The nearest definition is from a lost primary; clear the
7288 if (BINFO_LOST_PRIMARY_P (b))
7290 init = size_zero_node;
7297 /* Pull the offset for `this', and the function to call, out of
7299 delta = BV_DELTA (v);
7300 vcall_index = BV_VCALL_INDEX (v);
7302 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7303 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7305 /* You can't call an abstract virtual function; it's abstract.
7306 So, we replace these functions with __pure_virtual. */
7307 if (DECL_PURE_VIRTUAL_P (fn_original))
7310 if (abort_fndecl_addr == NULL)
7311 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7312 init = abort_fndecl_addr;
7316 if (!integer_zerop (delta) || vcall_index)
7318 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7319 if (!DECL_NAME (fn))
7322 /* Take the address of the function, considering it to be of an
7323 appropriate generic type. */
7324 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7328 /* And add it to the chain of initializers. */
7329 if (TARGET_VTABLE_USES_DESCRIPTORS)
7332 if (init == size_zero_node)
7333 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7334 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7336 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7338 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7339 TREE_OPERAND (init, 0),
7340 build_int_cst (NULL_TREE, i));
7341 TREE_CONSTANT (fdesc) = 1;
7342 TREE_INVARIANT (fdesc) = 1;
7344 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7348 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7351 /* The initializers for virtual functions were built up in reverse
7352 order; straighten them out now. */
7353 vfun_inits = nreverse (vfun_inits);
7355 /* The negative offset initializers are also in reverse order. */
7356 vid.inits = nreverse (vid.inits);
7358 /* Chain the two together. */
7359 return chainon (vid.inits, vfun_inits);
7362 /* Adds to vid->inits the initializers for the vbase and vcall
7363 offsets in BINFO, which is in the hierarchy dominated by T. */
7366 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7370 /* If this is a derived class, we must first create entries
7371 corresponding to the primary base class. */
7372 b = get_primary_binfo (binfo);
7374 build_vcall_and_vbase_vtbl_entries (b, vid);
7376 /* Add the vbase entries for this base. */
7377 build_vbase_offset_vtbl_entries (binfo, vid);
7378 /* Add the vcall entries for this base. */
7379 build_vcall_offset_vtbl_entries (binfo, vid);
7382 /* Returns the initializers for the vbase offset entries in the vtable
7383 for BINFO (which is part of the class hierarchy dominated by T), in
7384 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7385 where the next vbase offset will go. */
7388 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7392 tree non_primary_binfo;
7394 /* If there are no virtual baseclasses, then there is nothing to
7396 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7401 /* We might be a primary base class. Go up the inheritance hierarchy
7402 until we find the most derived class of which we are a primary base:
7403 it is the offset of that which we need to use. */
7404 non_primary_binfo = binfo;
7405 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7409 /* If we have reached a virtual base, then it must be a primary
7410 base (possibly multi-level) of vid->binfo, or we wouldn't
7411 have called build_vcall_and_vbase_vtbl_entries for it. But it
7412 might be a lost primary, so just skip down to vid->binfo. */
7413 if (BINFO_VIRTUAL_P (non_primary_binfo))
7415 non_primary_binfo = vid->binfo;
7419 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7420 if (get_primary_binfo (b) != non_primary_binfo)
7422 non_primary_binfo = b;
7425 /* Go through the virtual bases, adding the offsets. */
7426 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7428 vbase = TREE_CHAIN (vbase))
7433 if (!BINFO_VIRTUAL_P (vbase))
7436 /* Find the instance of this virtual base in the complete
7438 b = copied_binfo (vbase, binfo);
7440 /* If we've already got an offset for this virtual base, we
7441 don't need another one. */
7442 if (BINFO_VTABLE_PATH_MARKED (b))
7444 BINFO_VTABLE_PATH_MARKED (b) = 1;
7446 /* Figure out where we can find this vbase offset. */
7447 delta = size_binop (MULT_EXPR,
7450 TYPE_SIZE_UNIT (vtable_entry_type)));
7451 if (vid->primary_vtbl_p)
7452 BINFO_VPTR_FIELD (b) = delta;
7454 if (binfo != TYPE_BINFO (t))
7455 /* The vbase offset had better be the same. */
7456 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7458 /* The next vbase will come at a more negative offset. */
7459 vid->index = size_binop (MINUS_EXPR, vid->index,
7460 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7462 /* The initializer is the delta from BINFO to this virtual base.
7463 The vbase offsets go in reverse inheritance-graph order, and
7464 we are walking in inheritance graph order so these end up in
7466 delta = size_diffop (BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7469 = build_tree_list (NULL_TREE,
7470 fold_build1 (NOP_EXPR,
7473 vid->last_init = &TREE_CHAIN (*vid->last_init);
7477 /* Adds the initializers for the vcall offset entries in the vtable
7478 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7482 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7484 /* We only need these entries if this base is a virtual base. We
7485 compute the indices -- but do not add to the vtable -- when
7486 building the main vtable for a class. */
7487 if (BINFO_VIRTUAL_P (binfo) || binfo == TYPE_BINFO (vid->derived))
7489 /* We need a vcall offset for each of the virtual functions in this
7490 vtable. For example:
7492 class A { virtual void f (); };
7493 class B1 : virtual public A { virtual void f (); };
7494 class B2 : virtual public A { virtual void f (); };
7495 class C: public B1, public B2 { virtual void f (); };
7497 A C object has a primary base of B1, which has a primary base of A. A
7498 C also has a secondary base of B2, which no longer has a primary base
7499 of A. So the B2-in-C construction vtable needs a secondary vtable for
7500 A, which will adjust the A* to a B2* to call f. We have no way of
7501 knowing what (or even whether) this offset will be when we define B2,
7502 so we store this "vcall offset" in the A sub-vtable and look it up in
7503 a "virtual thunk" for B2::f.
7505 We need entries for all the functions in our primary vtable and
7506 in our non-virtual bases' secondary vtables. */
7508 /* If we are just computing the vcall indices -- but do not need
7509 the actual entries -- not that. */
7510 if (!BINFO_VIRTUAL_P (binfo))
7511 vid->generate_vcall_entries = false;
7512 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7513 add_vcall_offset_vtbl_entries_r (binfo, vid);
7517 /* Build vcall offsets, starting with those for BINFO. */
7520 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7526 /* Don't walk into virtual bases -- except, of course, for the
7527 virtual base for which we are building vcall offsets. Any
7528 primary virtual base will have already had its offsets generated
7529 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7530 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7533 /* If BINFO has a primary base, process it first. */
7534 primary_binfo = get_primary_binfo (binfo);
7536 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7538 /* Add BINFO itself to the list. */
7539 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7541 /* Scan the non-primary bases of BINFO. */
7542 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7543 if (base_binfo != primary_binfo)
7544 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7547 /* Called from build_vcall_offset_vtbl_entries_r. */
7550 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7552 /* Make entries for the rest of the virtuals. */
7553 if (abi_version_at_least (2))
7557 /* The ABI requires that the methods be processed in declaration
7558 order. G++ 3.2 used the order in the vtable. */
7559 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7561 orig_fn = TREE_CHAIN (orig_fn))
7562 if (DECL_VINDEX (orig_fn))
7563 add_vcall_offset (orig_fn, binfo, vid);
7567 tree derived_virtuals;
7570 /* If BINFO is a primary base, the most derived class which has
7571 BINFO as a primary base; otherwise, just BINFO. */
7572 tree non_primary_binfo;
7574 /* We might be a primary base class. Go up the inheritance hierarchy
7575 until we find the most derived class of which we are a primary base:
7576 it is the BINFO_VIRTUALS there that we need to consider. */
7577 non_primary_binfo = binfo;
7578 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7582 /* If we have reached a virtual base, then it must be vid->vbase,
7583 because we ignore other virtual bases in
7584 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7585 base (possibly multi-level) of vid->binfo, or we wouldn't
7586 have called build_vcall_and_vbase_vtbl_entries for it. But it
7587 might be a lost primary, so just skip down to vid->binfo. */
7588 if (BINFO_VIRTUAL_P (non_primary_binfo))
7590 gcc_assert (non_primary_binfo == vid->vbase);
7591 non_primary_binfo = vid->binfo;
7595 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7596 if (get_primary_binfo (b) != non_primary_binfo)
7598 non_primary_binfo = b;
7601 if (vid->ctor_vtbl_p)
7602 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7603 where rtti_binfo is the most derived type. */
7605 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7607 for (base_virtuals = BINFO_VIRTUALS (binfo),
7608 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7609 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7611 base_virtuals = TREE_CHAIN (base_virtuals),
7612 derived_virtuals = TREE_CHAIN (derived_virtuals),
7613 orig_virtuals = TREE_CHAIN (orig_virtuals))
7617 /* Find the declaration that originally caused this function to
7618 be present in BINFO_TYPE (binfo). */
7619 orig_fn = BV_FN (orig_virtuals);
7621 /* When processing BINFO, we only want to generate vcall slots for
7622 function slots introduced in BINFO. So don't try to generate
7623 one if the function isn't even defined in BINFO. */
7624 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7627 add_vcall_offset (orig_fn, binfo, vid);
7632 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7635 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7641 /* If there is already an entry for a function with the same
7642 signature as FN, then we do not need a second vcall offset.
7643 Check the list of functions already present in the derived
7645 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7647 if (same_signature_p (derived_entry, orig_fn)
7648 /* We only use one vcall offset for virtual destructors,
7649 even though there are two virtual table entries. */
7650 || (DECL_DESTRUCTOR_P (derived_entry)
7651 && DECL_DESTRUCTOR_P (orig_fn)))
7655 /* If we are building these vcall offsets as part of building
7656 the vtable for the most derived class, remember the vcall
7658 if (vid->binfo == TYPE_BINFO (vid->derived))
7660 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
7661 CLASSTYPE_VCALL_INDICES (vid->derived),
7663 elt->purpose = orig_fn;
7664 elt->value = vid->index;
7667 /* The next vcall offset will be found at a more negative
7669 vid->index = size_binop (MINUS_EXPR, vid->index,
7670 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7672 /* Keep track of this function. */
7673 VEC_safe_push (tree, gc, vid->fns, orig_fn);
7675 if (vid->generate_vcall_entries)
7680 /* Find the overriding function. */
7681 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
7682 if (fn == error_mark_node)
7683 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
7687 base = TREE_VALUE (fn);
7689 /* The vbase we're working on is a primary base of
7690 vid->binfo. But it might be a lost primary, so its
7691 BINFO_OFFSET might be wrong, so we just use the
7692 BINFO_OFFSET from vid->binfo. */
7693 vcall_offset = size_diffop (BINFO_OFFSET (base),
7694 BINFO_OFFSET (vid->binfo));
7695 vcall_offset = fold_build1 (NOP_EXPR, vtable_entry_type,
7698 /* Add the initializer to the vtable. */
7699 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
7700 vid->last_init = &TREE_CHAIN (*vid->last_init);
7704 /* Return vtbl initializers for the RTTI entries corresponding to the
7705 BINFO's vtable. The RTTI entries should indicate the object given
7706 by VID->rtti_binfo. */
7709 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
7718 basetype = BINFO_TYPE (binfo);
7719 t = BINFO_TYPE (vid->rtti_binfo);
7721 /* To find the complete object, we will first convert to our most
7722 primary base, and then add the offset in the vtbl to that value. */
7724 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
7725 && !BINFO_LOST_PRIMARY_P (b))
7729 primary_base = get_primary_binfo (b);
7730 gcc_assert (BINFO_PRIMARY_P (primary_base)
7731 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
7734 offset = size_diffop (BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
7736 /* The second entry is the address of the typeinfo object. */
7738 decl = build_address (get_tinfo_decl (t));
7740 decl = integer_zero_node;
7742 /* Convert the declaration to a type that can be stored in the
7744 init = build_nop (vfunc_ptr_type_node, decl);
7745 *vid->last_init = build_tree_list (NULL_TREE, init);
7746 vid->last_init = &TREE_CHAIN (*vid->last_init);
7748 /* Add the offset-to-top entry. It comes earlier in the vtable than
7749 the typeinfo entry. Convert the offset to look like a
7750 function pointer, so that we can put it in the vtable. */
7751 init = build_nop (vfunc_ptr_type_node, offset);
7752 *vid->last_init = build_tree_list (NULL_TREE, init);
7753 vid->last_init = &TREE_CHAIN (*vid->last_init);
7756 /* Fold a OBJ_TYPE_REF expression to the address of a function.
7757 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
7760 cp_fold_obj_type_ref (tree ref, tree known_type)
7762 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
7763 HOST_WIDE_INT i = 0;
7764 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
7769 i += (TARGET_VTABLE_USES_DESCRIPTORS
7770 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
7776 #ifdef ENABLE_CHECKING
7777 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
7778 DECL_VINDEX (fndecl)));
7781 cgraph_node (fndecl)->local.vtable_method = true;
7783 return build_address (fndecl);
7786 #include "gt-cp-class.h"