1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
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 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
370 v_offset, fold_convert (sizetype, 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))
409 offset = fold_convert (sizetype, offset);
410 if (code == MINUS_EXPR)
411 offset = fold_build1 (NEGATE_EXPR, sizetype, offset);
412 expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
418 expr = build_indirect_ref (expr, NULL);
422 expr = fold_build3 (COND_EXPR, target_type, null_test, expr,
423 fold_build1 (NOP_EXPR, target_type,
429 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
430 Perform a derived-to-base conversion by recursively building up a
431 sequence of COMPONENT_REFs to the appropriate base fields. */
434 build_simple_base_path (tree expr, tree binfo)
436 tree type = BINFO_TYPE (binfo);
437 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
440 if (d_binfo == NULL_TREE)
444 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
446 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
447 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
448 an lvalue in the front end; only _DECLs and _REFs are lvalues
450 temp = unary_complex_lvalue (ADDR_EXPR, expr);
452 expr = build_indirect_ref (temp, NULL);
458 expr = build_simple_base_path (expr, d_binfo);
460 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
461 field; field = TREE_CHAIN (field))
462 /* Is this the base field created by build_base_field? */
463 if (TREE_CODE (field) == FIELD_DECL
464 && DECL_FIELD_IS_BASE (field)
465 && TREE_TYPE (field) == type)
467 /* We don't use build_class_member_access_expr here, as that
468 has unnecessary checks, and more importantly results in
469 recursive calls to dfs_walk_once. */
470 int type_quals = cp_type_quals (TREE_TYPE (expr));
472 expr = build3 (COMPONENT_REF,
473 cp_build_qualified_type (type, type_quals),
474 expr, field, NULL_TREE);
475 expr = fold_if_not_in_template (expr);
477 /* Mark the expression const or volatile, as appropriate.
478 Even though we've dealt with the type above, we still have
479 to mark the expression itself. */
480 if (type_quals & TYPE_QUAL_CONST)
481 TREE_READONLY (expr) = 1;
482 if (type_quals & TYPE_QUAL_VOLATILE)
483 TREE_THIS_VOLATILE (expr) = 1;
488 /* Didn't find the base field?!? */
492 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
493 type is a class type or a pointer to a class type. In the former
494 case, TYPE is also a class type; in the latter it is another
495 pointer type. If CHECK_ACCESS is true, an error message is emitted
496 if TYPE is inaccessible. If OBJECT has pointer type, the value is
497 assumed to be non-NULL. */
500 convert_to_base (tree object, tree type, bool check_access, bool nonnull)
505 if (TYPE_PTR_P (TREE_TYPE (object)))
507 object_type = TREE_TYPE (TREE_TYPE (object));
508 type = TREE_TYPE (type);
511 object_type = TREE_TYPE (object);
513 binfo = lookup_base (object_type, type,
514 check_access ? ba_check : ba_unique,
516 if (!binfo || binfo == error_mark_node)
517 return error_mark_node;
519 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
522 /* EXPR is an expression with unqualified class type. BASE is a base
523 binfo of that class type. Returns EXPR, converted to the BASE
524 type. This function assumes that EXPR is the most derived class;
525 therefore virtual bases can be found at their static offsets. */
528 convert_to_base_statically (tree expr, tree base)
532 expr_type = TREE_TYPE (expr);
533 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
537 pointer_type = build_pointer_type (expr_type);
539 /* We use fold_build2 and fold_convert below to simplify the trees
540 provided to the optimizers. It is not safe to call these functions
541 when processing a template because they do not handle C++-specific
543 gcc_assert (!processing_template_decl);
544 expr = build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1);
545 if (!integer_zerop (BINFO_OFFSET (base)))
546 expr = fold_build2 (POINTER_PLUS_EXPR, pointer_type, expr,
547 fold_convert (sizetype, BINFO_OFFSET (base)));
548 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
549 expr = build_fold_indirect_ref (expr);
557 build_vfield_ref (tree datum, tree type)
559 tree vfield, vcontext;
561 if (datum == error_mark_node)
562 return error_mark_node;
564 /* First, convert to the requested type. */
565 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
566 datum = convert_to_base (datum, type, /*check_access=*/false,
569 /* Second, the requested type may not be the owner of its own vptr.
570 If not, convert to the base class that owns it. We cannot use
571 convert_to_base here, because VCONTEXT may appear more than once
572 in the inheritance hierarchy of TYPE, and thus direct conversion
573 between the types may be ambiguous. Following the path back up
574 one step at a time via primary bases avoids the problem. */
575 vfield = TYPE_VFIELD (type);
576 vcontext = DECL_CONTEXT (vfield);
577 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
579 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
580 type = TREE_TYPE (datum);
583 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
586 /* Given an object INSTANCE, return an expression which yields the
587 vtable element corresponding to INDEX. There are many special
588 cases for INSTANCE which we take care of here, mainly to avoid
589 creating extra tree nodes when we don't have to. */
592 build_vtbl_ref_1 (tree instance, tree idx)
595 tree vtbl = NULL_TREE;
597 /* Try to figure out what a reference refers to, and
598 access its virtual function table directly. */
601 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
603 tree basetype = non_reference (TREE_TYPE (instance));
605 if (fixed_type && !cdtorp)
607 tree binfo = lookup_base (fixed_type, basetype,
608 ba_unique | ba_quiet, NULL);
610 vtbl = unshare_expr (BINFO_VTABLE (binfo));
614 vtbl = build_vfield_ref (instance, basetype);
616 assemble_external (vtbl);
618 aref = build_array_ref (vtbl, idx);
619 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
620 TREE_INVARIANT (aref) = TREE_CONSTANT (aref);
626 build_vtbl_ref (tree instance, tree idx)
628 tree aref = build_vtbl_ref_1 (instance, idx);
633 /* Given a stable object pointer INSTANCE_PTR, return an expression which
634 yields a function pointer corresponding to vtable element INDEX. */
637 build_vfn_ref (tree instance_ptr, tree idx)
641 aref = build_vtbl_ref_1 (build_indirect_ref (instance_ptr, 0), idx);
643 /* When using function descriptors, the address of the
644 vtable entry is treated as a function pointer. */
645 if (TARGET_VTABLE_USES_DESCRIPTORS)
646 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
647 build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1));
649 /* Remember this as a method reference, for later devirtualization. */
650 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
655 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
656 for the given TYPE. */
659 get_vtable_name (tree type)
661 return mangle_vtbl_for_type (type);
664 /* DECL is an entity associated with TYPE, like a virtual table or an
665 implicitly generated constructor. Determine whether or not DECL
666 should have external or internal linkage at the object file
667 level. This routine does not deal with COMDAT linkage and other
668 similar complexities; it simply sets TREE_PUBLIC if it possible for
669 entities in other translation units to contain copies of DECL, in
673 set_linkage_according_to_type (tree type, tree decl)
675 /* If TYPE involves a local class in a function with internal
676 linkage, then DECL should have internal linkage too. Other local
677 classes have no linkage -- but if their containing functions
678 have external linkage, it makes sense for DECL to have external
679 linkage too. That will allow template definitions to be merged,
681 if (no_linkage_check (type, /*relaxed_p=*/true))
683 TREE_PUBLIC (decl) = 0;
684 DECL_INTERFACE_KNOWN (decl) = 1;
687 TREE_PUBLIC (decl) = 1;
690 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
691 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
692 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
695 build_vtable (tree class_type, tree name, tree vtable_type)
699 decl = build_lang_decl (VAR_DECL, name, vtable_type);
700 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
701 now to avoid confusion in mangle_decl. */
702 SET_DECL_ASSEMBLER_NAME (decl, name);
703 DECL_CONTEXT (decl) = class_type;
704 DECL_ARTIFICIAL (decl) = 1;
705 TREE_STATIC (decl) = 1;
706 TREE_READONLY (decl) = 1;
707 DECL_VIRTUAL_P (decl) = 1;
708 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
709 DECL_VTABLE_OR_VTT_P (decl) = 1;
710 /* At one time the vtable info was grabbed 2 words at a time. This
711 fails on sparc unless you have 8-byte alignment. (tiemann) */
712 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
714 set_linkage_according_to_type (class_type, decl);
715 /* The vtable has not been defined -- yet. */
716 DECL_EXTERNAL (decl) = 1;
717 DECL_NOT_REALLY_EXTERN (decl) = 1;
719 /* Mark the VAR_DECL node representing the vtable itself as a
720 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
721 is rather important that such things be ignored because any
722 effort to actually generate DWARF for them will run into
723 trouble when/if we encounter code like:
726 struct S { virtual void member (); };
728 because the artificial declaration of the vtable itself (as
729 manufactured by the g++ front end) will say that the vtable is
730 a static member of `S' but only *after* the debug output for
731 the definition of `S' has already been output. This causes
732 grief because the DWARF entry for the definition of the vtable
733 will try to refer back to an earlier *declaration* of the
734 vtable as a static member of `S' and there won't be one. We
735 might be able to arrange to have the "vtable static member"
736 attached to the member list for `S' before the debug info for
737 `S' get written (which would solve the problem) but that would
738 require more intrusive changes to the g++ front end. */
739 DECL_IGNORED_P (decl) = 1;
744 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
745 or even complete. If this does not exist, create it. If COMPLETE is
746 nonzero, then complete the definition of it -- that will render it
747 impossible to actually build the vtable, but is useful to get at those
748 which are known to exist in the runtime. */
751 get_vtable_decl (tree type, int complete)
755 if (CLASSTYPE_VTABLES (type))
756 return CLASSTYPE_VTABLES (type);
758 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
759 CLASSTYPE_VTABLES (type) = decl;
763 DECL_EXTERNAL (decl) = 1;
764 finish_decl (decl, NULL_TREE, NULL_TREE);
770 /* Build the primary virtual function table for TYPE. If BINFO is
771 non-NULL, build the vtable starting with the initial approximation
772 that it is the same as the one which is the head of the association
773 list. Returns a nonzero value if a new vtable is actually
777 build_primary_vtable (tree binfo, tree type)
782 decl = get_vtable_decl (type, /*complete=*/0);
786 if (BINFO_NEW_VTABLE_MARKED (binfo))
787 /* We have already created a vtable for this base, so there's
788 no need to do it again. */
791 virtuals = copy_list (BINFO_VIRTUALS (binfo));
792 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
793 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
794 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
798 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
799 virtuals = NULL_TREE;
802 #ifdef GATHER_STATISTICS
804 n_vtable_elems += list_length (virtuals);
807 /* Initialize the association list for this type, based
808 on our first approximation. */
809 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
810 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
811 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
815 /* Give BINFO a new virtual function table which is initialized
816 with a skeleton-copy of its original initialization. The only
817 entry that changes is the `delta' entry, so we can really
818 share a lot of structure.
820 FOR_TYPE is the most derived type which caused this table to
823 Returns nonzero if we haven't met BINFO before.
825 The order in which vtables are built (by calling this function) for
826 an object must remain the same, otherwise a binary incompatibility
830 build_secondary_vtable (tree binfo)
832 if (BINFO_NEW_VTABLE_MARKED (binfo))
833 /* We already created a vtable for this base. There's no need to
837 /* Remember that we've created a vtable for this BINFO, so that we
838 don't try to do so again. */
839 SET_BINFO_NEW_VTABLE_MARKED (binfo);
841 /* Make fresh virtual list, so we can smash it later. */
842 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
844 /* Secondary vtables are laid out as part of the same structure as
845 the primary vtable. */
846 BINFO_VTABLE (binfo) = NULL_TREE;
850 /* Create a new vtable for BINFO which is the hierarchy dominated by
851 T. Return nonzero if we actually created a new vtable. */
854 make_new_vtable (tree t, tree binfo)
856 if (binfo == TYPE_BINFO (t))
857 /* In this case, it is *type*'s vtable we are modifying. We start
858 with the approximation that its vtable is that of the
859 immediate base class. */
860 return build_primary_vtable (binfo, t);
862 /* This is our very own copy of `basetype' to play with. Later,
863 we will fill in all the virtual functions that override the
864 virtual functions in these base classes which are not defined
865 by the current type. */
866 return build_secondary_vtable (binfo);
869 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
870 (which is in the hierarchy dominated by T) list FNDECL as its
871 BV_FN. DELTA is the required constant adjustment from the `this'
872 pointer where the vtable entry appears to the `this' required when
873 the function is actually called. */
876 modify_vtable_entry (tree t,
886 if (fndecl != BV_FN (v)
887 || !tree_int_cst_equal (delta, BV_DELTA (v)))
889 /* We need a new vtable for BINFO. */
890 if (make_new_vtable (t, binfo))
892 /* If we really did make a new vtable, we also made a copy
893 of the BINFO_VIRTUALS list. Now, we have to find the
894 corresponding entry in that list. */
895 *virtuals = BINFO_VIRTUALS (binfo);
896 while (BV_FN (*virtuals) != BV_FN (v))
897 *virtuals = TREE_CHAIN (*virtuals);
901 BV_DELTA (v) = delta;
902 BV_VCALL_INDEX (v) = NULL_TREE;
908 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
909 the USING_DECL naming METHOD. Returns true if the method could be
910 added to the method vec. */
913 add_method (tree type, tree method, tree using_decl)
917 bool template_conv_p = false;
919 VEC(tree,gc) *method_vec;
921 bool insert_p = false;
925 if (method == error_mark_node)
928 complete_p = COMPLETE_TYPE_P (type);
929 conv_p = DECL_CONV_FN_P (method);
931 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
932 && DECL_TEMPLATE_CONV_FN_P (method));
934 method_vec = CLASSTYPE_METHOD_VEC (type);
937 /* Make a new method vector. We start with 8 entries. We must
938 allocate at least two (for constructors and destructors), and
939 we're going to end up with an assignment operator at some
941 method_vec = VEC_alloc (tree, gc, 8);
942 /* Create slots for constructors and destructors. */
943 VEC_quick_push (tree, method_vec, NULL_TREE);
944 VEC_quick_push (tree, method_vec, NULL_TREE);
945 CLASSTYPE_METHOD_VEC (type) = method_vec;
948 /* Maintain TYPE_HAS_CONSTRUCTOR, etc. */
949 grok_special_member_properties (method);
951 /* Constructors and destructors go in special slots. */
952 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
953 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
954 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
956 slot = CLASSTYPE_DESTRUCTOR_SLOT;
958 if (TYPE_FOR_JAVA (type))
960 if (!DECL_ARTIFICIAL (method))
961 error ("Java class %qT cannot have a destructor", type);
962 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
963 error ("Java class %qT cannot have an implicit non-trivial "
973 /* See if we already have an entry with this name. */
974 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
975 VEC_iterate (tree, method_vec, slot, m);
981 if (TREE_CODE (m) == TEMPLATE_DECL
982 && DECL_TEMPLATE_CONV_FN_P (m))
986 if (conv_p && !DECL_CONV_FN_P (m))
988 if (DECL_NAME (m) == DECL_NAME (method))
994 && !DECL_CONV_FN_P (m)
995 && DECL_NAME (m) > DECL_NAME (method))
999 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1001 /* Check to see if we've already got this method. */
1002 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1004 tree fn = OVL_CURRENT (fns);
1010 if (TREE_CODE (fn) != TREE_CODE (method))
1013 /* [over.load] Member function declarations with the
1014 same name and the same parameter types cannot be
1015 overloaded if any of them is a static member
1016 function declaration.
1018 [namespace.udecl] When a using-declaration brings names
1019 from a base class into a derived class scope, member
1020 functions in the derived class override and/or hide member
1021 functions with the same name and parameter types in a base
1022 class (rather than conflicting). */
1023 fn_type = TREE_TYPE (fn);
1024 method_type = TREE_TYPE (method);
1025 parms1 = TYPE_ARG_TYPES (fn_type);
1026 parms2 = TYPE_ARG_TYPES (method_type);
1028 /* Compare the quals on the 'this' parm. Don't compare
1029 the whole types, as used functions are treated as
1030 coming from the using class in overload resolution. */
1031 if (! DECL_STATIC_FUNCTION_P (fn)
1032 && ! DECL_STATIC_FUNCTION_P (method)
1033 && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
1034 != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
1037 /* For templates, the return type and template parameters
1038 must be identical. */
1039 if (TREE_CODE (fn) == TEMPLATE_DECL
1040 && (!same_type_p (TREE_TYPE (fn_type),
1041 TREE_TYPE (method_type))
1042 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1043 DECL_TEMPLATE_PARMS (method))))
1046 if (! DECL_STATIC_FUNCTION_P (fn))
1047 parms1 = TREE_CHAIN (parms1);
1048 if (! DECL_STATIC_FUNCTION_P (method))
1049 parms2 = TREE_CHAIN (parms2);
1051 if (compparms (parms1, parms2)
1052 && (!DECL_CONV_FN_P (fn)
1053 || same_type_p (TREE_TYPE (fn_type),
1054 TREE_TYPE (method_type))))
1058 if (DECL_CONTEXT (fn) == type)
1059 /* Defer to the local function. */
1061 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1062 error ("repeated using declaration %q+D", using_decl);
1064 error ("using declaration %q+D conflicts with a previous using declaration",
1069 error ("%q+#D cannot be overloaded", method);
1070 error ("with %q+#D", fn);
1073 /* We don't call duplicate_decls here to merge the
1074 declarations because that will confuse things if the
1075 methods have inline definitions. In particular, we
1076 will crash while processing the definitions. */
1081 /* A class should never have more than one destructor. */
1082 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1085 /* Add the new binding. */
1086 overload = build_overload (method, current_fns);
1089 TYPE_HAS_CONVERSION (type) = 1;
1090 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1091 push_class_level_binding (DECL_NAME (method), overload);
1097 /* We only expect to add few methods in the COMPLETE_P case, so
1098 just make room for one more method in that case. */
1100 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1102 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1104 CLASSTYPE_METHOD_VEC (type) = method_vec;
1105 if (slot == VEC_length (tree, method_vec))
1106 VEC_quick_push (tree, method_vec, overload);
1108 VEC_quick_insert (tree, method_vec, slot, overload);
1111 /* Replace the current slot. */
1112 VEC_replace (tree, method_vec, slot, overload);
1116 /* Subroutines of finish_struct. */
1118 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1119 legit, otherwise return 0. */
1122 alter_access (tree t, tree fdecl, tree access)
1126 if (!DECL_LANG_SPECIFIC (fdecl))
1127 retrofit_lang_decl (fdecl);
1129 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1131 elem = purpose_member (t, DECL_ACCESS (fdecl));
1134 if (TREE_VALUE (elem) != access)
1136 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1137 error ("conflicting access specifications for method"
1138 " %q+D, ignored", TREE_TYPE (fdecl));
1140 error ("conflicting access specifications for field %qE, ignored",
1145 /* They're changing the access to the same thing they changed
1146 it to before. That's OK. */
1152 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1153 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1159 /* Process the USING_DECL, which is a member of T. */
1162 handle_using_decl (tree using_decl, tree t)
1164 tree decl = USING_DECL_DECLS (using_decl);
1165 tree name = DECL_NAME (using_decl);
1167 = TREE_PRIVATE (using_decl) ? access_private_node
1168 : TREE_PROTECTED (using_decl) ? access_protected_node
1169 : access_public_node;
1170 tree flist = NULL_TREE;
1173 gcc_assert (!processing_template_decl && decl);
1175 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1178 if (is_overloaded_fn (old_value))
1179 old_value = OVL_CURRENT (old_value);
1181 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1184 old_value = NULL_TREE;
1187 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1189 if (is_overloaded_fn (decl))
1194 else if (is_overloaded_fn (old_value))
1197 /* It's OK to use functions from a base when there are functions with
1198 the same name already present in the current class. */;
1201 error ("%q+D invalid in %q#T", using_decl, t);
1202 error (" because of local method %q+#D with same name",
1203 OVL_CURRENT (old_value));
1207 else if (!DECL_ARTIFICIAL (old_value))
1209 error ("%q+D invalid in %q#T", using_decl, t);
1210 error (" because of local member %q+#D with same name", old_value);
1214 /* Make type T see field decl FDECL with access ACCESS. */
1216 for (; flist; flist = OVL_NEXT (flist))
1218 add_method (t, OVL_CURRENT (flist), using_decl);
1219 alter_access (t, OVL_CURRENT (flist), access);
1222 alter_access (t, decl, access);
1225 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1226 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1227 properties of the bases. */
1230 check_bases (tree t,
1231 int* cant_have_const_ctor_p,
1232 int* no_const_asn_ref_p)
1235 int seen_non_virtual_nearly_empty_base_p;
1239 seen_non_virtual_nearly_empty_base_p = 0;
1241 for (binfo = TYPE_BINFO (t), i = 0;
1242 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1244 tree basetype = TREE_TYPE (base_binfo);
1246 gcc_assert (COMPLETE_TYPE_P (basetype));
1248 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1249 here because the case of virtual functions but non-virtual
1250 dtor is handled in finish_struct_1. */
1251 if (!TYPE_POLYMORPHIC_P (basetype))
1252 warning (OPT_Weffc__,
1253 "base class %q#T has a non-virtual destructor", basetype);
1255 /* If the base class doesn't have copy constructors or
1256 assignment operators that take const references, then the
1257 derived class cannot have such a member automatically
1259 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1260 *cant_have_const_ctor_p = 1;
1261 if (TYPE_HAS_ASSIGN_REF (basetype)
1262 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1263 *no_const_asn_ref_p = 1;
1265 if (BINFO_VIRTUAL_P (base_binfo))
1266 /* A virtual base does not effect nearly emptiness. */
1268 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1270 if (seen_non_virtual_nearly_empty_base_p)
1271 /* And if there is more than one nearly empty base, then the
1272 derived class is not nearly empty either. */
1273 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1275 /* Remember we've seen one. */
1276 seen_non_virtual_nearly_empty_base_p = 1;
1278 else if (!is_empty_class (basetype))
1279 /* If the base class is not empty or nearly empty, then this
1280 class cannot be nearly empty. */
1281 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1283 /* A lot of properties from the bases also apply to the derived
1285 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1286 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1287 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1288 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1289 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1290 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1291 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1292 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1293 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1294 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (basetype);
1298 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1299 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1300 that have had a nearly-empty virtual primary base stolen by some
1301 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1305 determine_primary_bases (tree t)
1308 tree primary = NULL_TREE;
1309 tree type_binfo = TYPE_BINFO (t);
1312 /* Determine the primary bases of our bases. */
1313 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1314 base_binfo = TREE_CHAIN (base_binfo))
1316 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1318 /* See if we're the non-virtual primary of our inheritance
1320 if (!BINFO_VIRTUAL_P (base_binfo))
1322 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1323 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1326 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1327 BINFO_TYPE (parent_primary)))
1328 /* We are the primary binfo. */
1329 BINFO_PRIMARY_P (base_binfo) = 1;
1331 /* Determine if we have a virtual primary base, and mark it so.
1333 if (primary && BINFO_VIRTUAL_P (primary))
1335 tree this_primary = copied_binfo (primary, base_binfo);
1337 if (BINFO_PRIMARY_P (this_primary))
1338 /* Someone already claimed this base. */
1339 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1344 BINFO_PRIMARY_P (this_primary) = 1;
1345 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1347 /* A virtual binfo might have been copied from within
1348 another hierarchy. As we're about to use it as a
1349 primary base, make sure the offsets match. */
1350 delta = size_diffop (convert (ssizetype,
1351 BINFO_OFFSET (base_binfo)),
1353 BINFO_OFFSET (this_primary)));
1355 propagate_binfo_offsets (this_primary, delta);
1360 /* First look for a dynamic direct non-virtual base. */
1361 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1363 tree basetype = BINFO_TYPE (base_binfo);
1365 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1367 primary = base_binfo;
1372 /* A "nearly-empty" virtual base class can be the primary base
1373 class, if no non-virtual polymorphic base can be found. Look for
1374 a nearly-empty virtual dynamic base that is not already a primary
1375 base of something in the hierarchy. If there is no such base,
1376 just pick the first nearly-empty virtual base. */
1378 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1379 base_binfo = TREE_CHAIN (base_binfo))
1380 if (BINFO_VIRTUAL_P (base_binfo)
1381 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1383 if (!BINFO_PRIMARY_P (base_binfo))
1385 /* Found one that is not primary. */
1386 primary = base_binfo;
1390 /* Remember the first candidate. */
1391 primary = base_binfo;
1395 /* If we've got a primary base, use it. */
1398 tree basetype = BINFO_TYPE (primary);
1400 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1401 if (BINFO_PRIMARY_P (primary))
1402 /* We are stealing a primary base. */
1403 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1404 BINFO_PRIMARY_P (primary) = 1;
1405 if (BINFO_VIRTUAL_P (primary))
1409 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1410 /* A virtual binfo might have been copied from within
1411 another hierarchy. As we're about to use it as a primary
1412 base, make sure the offsets match. */
1413 delta = size_diffop (ssize_int (0),
1414 convert (ssizetype, BINFO_OFFSET (primary)));
1416 propagate_binfo_offsets (primary, delta);
1419 primary = TYPE_BINFO (basetype);
1421 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1422 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1423 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1427 /* Set memoizing fields and bits of T (and its variants) for later
1431 finish_struct_bits (tree t)
1435 /* Fix up variants (if any). */
1436 for (variants = TYPE_NEXT_VARIANT (t);
1438 variants = TYPE_NEXT_VARIANT (variants))
1440 /* These fields are in the _TYPE part of the node, not in
1441 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1442 TYPE_HAS_CONSTRUCTOR (variants) = TYPE_HAS_CONSTRUCTOR (t);
1443 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1444 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1445 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1447 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1449 TYPE_BINFO (variants) = TYPE_BINFO (t);
1451 /* Copy whatever these are holding today. */
1452 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1453 TYPE_METHODS (variants) = TYPE_METHODS (t);
1454 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1457 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1458 /* For a class w/o baseclasses, 'finish_struct' has set
1459 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1460 Similarly for a class whose base classes do not have vtables.
1461 When neither of these is true, we might have removed abstract
1462 virtuals (by providing a definition), added some (by declaring
1463 new ones), or redeclared ones from a base class. We need to
1464 recalculate what's really an abstract virtual at this point (by
1465 looking in the vtables). */
1466 get_pure_virtuals (t);
1468 /* If this type has a copy constructor or a destructor, force its
1469 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1470 nonzero. This will cause it to be passed by invisible reference
1471 and prevent it from being returned in a register. */
1472 if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1475 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1476 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1478 TYPE_MODE (variants) = BLKmode;
1479 TREE_ADDRESSABLE (variants) = 1;
1484 /* Issue warnings about T having private constructors, but no friends,
1487 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1488 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1489 non-private static member functions. */
1492 maybe_warn_about_overly_private_class (tree t)
1494 int has_member_fn = 0;
1495 int has_nonprivate_method = 0;
1498 if (!warn_ctor_dtor_privacy
1499 /* If the class has friends, those entities might create and
1500 access instances, so we should not warn. */
1501 || (CLASSTYPE_FRIEND_CLASSES (t)
1502 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1503 /* We will have warned when the template was declared; there's
1504 no need to warn on every instantiation. */
1505 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1506 /* There's no reason to even consider warning about this
1510 /* We only issue one warning, if more than one applies, because
1511 otherwise, on code like:
1514 // Oops - forgot `public:'
1520 we warn several times about essentially the same problem. */
1522 /* Check to see if all (non-constructor, non-destructor) member
1523 functions are private. (Since there are no friends or
1524 non-private statics, we can't ever call any of the private member
1526 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1527 /* We're not interested in compiler-generated methods; they don't
1528 provide any way to call private members. */
1529 if (!DECL_ARTIFICIAL (fn))
1531 if (!TREE_PRIVATE (fn))
1533 if (DECL_STATIC_FUNCTION_P (fn))
1534 /* A non-private static member function is just like a
1535 friend; it can create and invoke private member
1536 functions, and be accessed without a class
1540 has_nonprivate_method = 1;
1541 /* Keep searching for a static member function. */
1543 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1547 if (!has_nonprivate_method && has_member_fn)
1549 /* There are no non-private methods, and there's at least one
1550 private member function that isn't a constructor or
1551 destructor. (If all the private members are
1552 constructors/destructors we want to use the code below that
1553 issues error messages specifically referring to
1554 constructors/destructors.) */
1556 tree binfo = TYPE_BINFO (t);
1558 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1559 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1561 has_nonprivate_method = 1;
1564 if (!has_nonprivate_method)
1566 warning (OPT_Wctor_dtor_privacy,
1567 "all member functions in class %qT are private", t);
1572 /* Even if some of the member functions are non-private, the class
1573 won't be useful for much if all the constructors or destructors
1574 are private: such an object can never be created or destroyed. */
1575 fn = CLASSTYPE_DESTRUCTORS (t);
1576 if (fn && TREE_PRIVATE (fn))
1578 warning (OPT_Wctor_dtor_privacy,
1579 "%q#T only defines a private destructor and has no friends",
1584 if (TYPE_HAS_CONSTRUCTOR (t)
1585 /* Implicitly generated constructors are always public. */
1586 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1587 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1589 int nonprivate_ctor = 0;
1591 /* If a non-template class does not define a copy
1592 constructor, one is defined for it, enabling it to avoid
1593 this warning. For a template class, this does not
1594 happen, and so we would normally get a warning on:
1596 template <class T> class C { private: C(); };
1598 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1599 complete non-template or fully instantiated classes have this
1601 if (!TYPE_HAS_INIT_REF (t))
1602 nonprivate_ctor = 1;
1604 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1606 tree ctor = OVL_CURRENT (fn);
1607 /* Ideally, we wouldn't count copy constructors (or, in
1608 fact, any constructor that takes an argument of the
1609 class type as a parameter) because such things cannot
1610 be used to construct an instance of the class unless
1611 you already have one. But, for now at least, we're
1613 if (! TREE_PRIVATE (ctor))
1615 nonprivate_ctor = 1;
1620 if (nonprivate_ctor == 0)
1622 warning (OPT_Wctor_dtor_privacy,
1623 "%q#T only defines private constructors and has no friends",
1631 gt_pointer_operator new_value;
1635 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1638 method_name_cmp (const void* m1_p, const void* m2_p)
1640 const tree *const m1 = (const tree *) m1_p;
1641 const tree *const m2 = (const tree *) m2_p;
1643 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1645 if (*m1 == NULL_TREE)
1647 if (*m2 == NULL_TREE)
1649 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1654 /* This routine compares two fields like method_name_cmp but using the
1655 pointer operator in resort_field_decl_data. */
1658 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1660 const tree *const m1 = (const tree *) m1_p;
1661 const tree *const m2 = (const tree *) m2_p;
1662 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1664 if (*m1 == NULL_TREE)
1666 if (*m2 == NULL_TREE)
1669 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1670 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1671 resort_data.new_value (&d1, resort_data.cookie);
1672 resort_data.new_value (&d2, resort_data.cookie);
1679 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1682 resort_type_method_vec (void* obj,
1683 void* orig_obj ATTRIBUTE_UNUSED ,
1684 gt_pointer_operator new_value,
1687 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1688 int len = VEC_length (tree, method_vec);
1692 /* The type conversion ops have to live at the front of the vec, so we
1694 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1695 VEC_iterate (tree, method_vec, slot, fn);
1697 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1702 resort_data.new_value = new_value;
1703 resort_data.cookie = cookie;
1704 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1705 resort_method_name_cmp);
1709 /* Warn about duplicate methods in fn_fields.
1711 Sort methods that are not special (i.e., constructors, destructors,
1712 and type conversion operators) so that we can find them faster in
1716 finish_struct_methods (tree t)
1719 VEC(tree,gc) *method_vec;
1722 method_vec = CLASSTYPE_METHOD_VEC (t);
1726 len = VEC_length (tree, method_vec);
1728 /* Clear DECL_IN_AGGR_P for all functions. */
1729 for (fn_fields = TYPE_METHODS (t); fn_fields;
1730 fn_fields = TREE_CHAIN (fn_fields))
1731 DECL_IN_AGGR_P (fn_fields) = 0;
1733 /* Issue warnings about private constructors and such. If there are
1734 no methods, then some public defaults are generated. */
1735 maybe_warn_about_overly_private_class (t);
1737 /* The type conversion ops have to live at the front of the vec, so we
1739 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1740 VEC_iterate (tree, method_vec, slot, fn_fields);
1742 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1745 qsort (VEC_address (tree, method_vec) + slot,
1746 len-slot, sizeof (tree), method_name_cmp);
1749 /* Make BINFO's vtable have N entries, including RTTI entries,
1750 vbase and vcall offsets, etc. Set its type and call the back end
1754 layout_vtable_decl (tree binfo, int n)
1759 atype = build_cplus_array_type (vtable_entry_type,
1760 build_index_type (size_int (n - 1)));
1761 layout_type (atype);
1763 /* We may have to grow the vtable. */
1764 vtable = get_vtbl_decl_for_binfo (binfo);
1765 if (!same_type_p (TREE_TYPE (vtable), atype))
1767 TREE_TYPE (vtable) = atype;
1768 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1769 layout_decl (vtable, 0);
1773 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1774 have the same signature. */
1777 same_signature_p (tree fndecl, tree base_fndecl)
1779 /* One destructor overrides another if they are the same kind of
1781 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1782 && special_function_p (base_fndecl) == special_function_p (fndecl))
1784 /* But a non-destructor never overrides a destructor, nor vice
1785 versa, nor do different kinds of destructors override
1786 one-another. For example, a complete object destructor does not
1787 override a deleting destructor. */
1788 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1791 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1792 || (DECL_CONV_FN_P (fndecl)
1793 && DECL_CONV_FN_P (base_fndecl)
1794 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1795 DECL_CONV_FN_TYPE (base_fndecl))))
1797 tree types, base_types;
1798 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1799 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1800 if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1801 == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1802 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1808 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1812 base_derived_from (tree derived, tree base)
1816 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1818 if (probe == derived)
1820 else if (BINFO_VIRTUAL_P (probe))
1821 /* If we meet a virtual base, we can't follow the inheritance
1822 any more. See if the complete type of DERIVED contains
1823 such a virtual base. */
1824 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1830 typedef struct find_final_overrider_data_s {
1831 /* The function for which we are trying to find a final overrider. */
1833 /* The base class in which the function was declared. */
1834 tree declaring_base;
1835 /* The candidate overriders. */
1837 /* Path to most derived. */
1838 VEC(tree,heap) *path;
1839 } find_final_overrider_data;
1841 /* Add the overrider along the current path to FFOD->CANDIDATES.
1842 Returns true if an overrider was found; false otherwise. */
1845 dfs_find_final_overrider_1 (tree binfo,
1846 find_final_overrider_data *ffod,
1851 /* If BINFO is not the most derived type, try a more derived class.
1852 A definition there will overrider a definition here. */
1856 if (dfs_find_final_overrider_1
1857 (VEC_index (tree, ffod->path, depth), ffod, depth))
1861 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1864 tree *candidate = &ffod->candidates;
1866 /* Remove any candidates overridden by this new function. */
1869 /* If *CANDIDATE overrides METHOD, then METHOD
1870 cannot override anything else on the list. */
1871 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1873 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1874 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1875 *candidate = TREE_CHAIN (*candidate);
1877 candidate = &TREE_CHAIN (*candidate);
1880 /* Add the new function. */
1881 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1888 /* Called from find_final_overrider via dfs_walk. */
1891 dfs_find_final_overrider_pre (tree binfo, void *data)
1893 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1895 if (binfo == ffod->declaring_base)
1896 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1897 VEC_safe_push (tree, heap, ffod->path, binfo);
1903 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1905 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1906 VEC_pop (tree, ffod->path);
1911 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1912 FN and whose TREE_VALUE is the binfo for the base where the
1913 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1914 DERIVED) is the base object in which FN is declared. */
1917 find_final_overrider (tree derived, tree binfo, tree fn)
1919 find_final_overrider_data ffod;
1921 /* Getting this right is a little tricky. This is valid:
1923 struct S { virtual void f (); };
1924 struct T { virtual void f (); };
1925 struct U : public S, public T { };
1927 even though calling `f' in `U' is ambiguous. But,
1929 struct R { virtual void f(); };
1930 struct S : virtual public R { virtual void f (); };
1931 struct T : virtual public R { virtual void f (); };
1932 struct U : public S, public T { };
1934 is not -- there's no way to decide whether to put `S::f' or
1935 `T::f' in the vtable for `R'.
1937 The solution is to look at all paths to BINFO. If we find
1938 different overriders along any two, then there is a problem. */
1939 if (DECL_THUNK_P (fn))
1940 fn = THUNK_TARGET (fn);
1942 /* Determine the depth of the hierarchy. */
1944 ffod.declaring_base = binfo;
1945 ffod.candidates = NULL_TREE;
1946 ffod.path = VEC_alloc (tree, heap, 30);
1948 dfs_walk_all (derived, dfs_find_final_overrider_pre,
1949 dfs_find_final_overrider_post, &ffod);
1951 VEC_free (tree, heap, ffod.path);
1953 /* If there was no winner, issue an error message. */
1954 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
1955 return error_mark_node;
1957 return ffod.candidates;
1960 /* Return the index of the vcall offset for FN when TYPE is used as a
1964 get_vcall_index (tree fn, tree type)
1966 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
1970 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
1971 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
1972 || same_signature_p (fn, p->purpose))
1975 /* There should always be an appropriate index. */
1979 /* Update an entry in the vtable for BINFO, which is in the hierarchy
1980 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
1981 corresponding position in the BINFO_VIRTUALS list. */
1984 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
1992 tree overrider_fn, overrider_target;
1993 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
1994 tree over_return, base_return;
1997 /* Find the nearest primary base (possibly binfo itself) which defines
1998 this function; this is the class the caller will convert to when
1999 calling FN through BINFO. */
2000 for (b = binfo; ; b = get_primary_binfo (b))
2003 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2006 /* The nearest definition is from a lost primary. */
2007 if (BINFO_LOST_PRIMARY_P (b))
2012 /* Find the final overrider. */
2013 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2014 if (overrider == error_mark_node)
2016 error ("no unique final overrider for %qD in %qT", target_fn, t);
2019 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2021 /* Check for adjusting covariant return types. */
2022 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2023 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2025 if (POINTER_TYPE_P (over_return)
2026 && TREE_CODE (over_return) == TREE_CODE (base_return)
2027 && CLASS_TYPE_P (TREE_TYPE (over_return))
2028 && CLASS_TYPE_P (TREE_TYPE (base_return))
2029 /* If the overrider is invalid, don't even try. */
2030 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2032 /* If FN is a covariant thunk, we must figure out the adjustment
2033 to the final base FN was converting to. As OVERRIDER_TARGET might
2034 also be converting to the return type of FN, we have to
2035 combine the two conversions here. */
2036 tree fixed_offset, virtual_offset;
2038 over_return = TREE_TYPE (over_return);
2039 base_return = TREE_TYPE (base_return);
2041 if (DECL_THUNK_P (fn))
2043 gcc_assert (DECL_RESULT_THUNK_P (fn));
2044 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2045 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2048 fixed_offset = virtual_offset = NULL_TREE;
2051 /* Find the equivalent binfo within the return type of the
2052 overriding function. We will want the vbase offset from
2054 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2056 else if (!same_type_ignoring_top_level_qualifiers_p
2057 (over_return, base_return))
2059 /* There was no existing virtual thunk (which takes
2060 precedence). So find the binfo of the base function's
2061 return type within the overriding function's return type.
2062 We cannot call lookup base here, because we're inside a
2063 dfs_walk, and will therefore clobber the BINFO_MARKED
2064 flags. Fortunately we know the covariancy is valid (it
2065 has already been checked), so we can just iterate along
2066 the binfos, which have been chained in inheritance graph
2067 order. Of course it is lame that we have to repeat the
2068 search here anyway -- we should really be caching pieces
2069 of the vtable and avoiding this repeated work. */
2070 tree thunk_binfo, base_binfo;
2072 /* Find the base binfo within the overriding function's
2073 return type. We will always find a thunk_binfo, except
2074 when the covariancy is invalid (which we will have
2075 already diagnosed). */
2076 for (base_binfo = TYPE_BINFO (base_return),
2077 thunk_binfo = TYPE_BINFO (over_return);
2079 thunk_binfo = TREE_CHAIN (thunk_binfo))
2080 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2081 BINFO_TYPE (base_binfo)))
2084 /* See if virtual inheritance is involved. */
2085 for (virtual_offset = thunk_binfo;
2087 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2088 if (BINFO_VIRTUAL_P (virtual_offset))
2092 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2094 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2098 /* We convert via virtual base. Adjust the fixed
2099 offset to be from there. */
2100 offset = size_diffop
2102 (ssizetype, BINFO_OFFSET (virtual_offset)));
2105 /* There was an existing fixed offset, this must be
2106 from the base just converted to, and the base the
2107 FN was thunking to. */
2108 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2110 fixed_offset = offset;
2114 if (fixed_offset || virtual_offset)
2115 /* Replace the overriding function with a covariant thunk. We
2116 will emit the overriding function in its own slot as
2118 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2119 fixed_offset, virtual_offset);
2122 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2123 !DECL_THUNK_P (fn));
2125 /* Assume that we will produce a thunk that convert all the way to
2126 the final overrider, and not to an intermediate virtual base. */
2127 virtual_base = NULL_TREE;
2129 /* See if we can convert to an intermediate virtual base first, and then
2130 use the vcall offset located there to finish the conversion. */
2131 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2133 /* If we find the final overrider, then we can stop
2135 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2136 BINFO_TYPE (TREE_VALUE (overrider))))
2139 /* If we find a virtual base, and we haven't yet found the
2140 overrider, then there is a virtual base between the
2141 declaring base (first_defn) and the final overrider. */
2142 if (BINFO_VIRTUAL_P (b))
2149 if (overrider_fn != overrider_target && !virtual_base)
2151 /* The ABI specifies that a covariant thunk includes a mangling
2152 for a this pointer adjustment. This-adjusting thunks that
2153 override a function from a virtual base have a vcall
2154 adjustment. When the virtual base in question is a primary
2155 virtual base, we know the adjustments are zero, (and in the
2156 non-covariant case, we would not use the thunk).
2157 Unfortunately we didn't notice this could happen, when
2158 designing the ABI and so never mandated that such a covariant
2159 thunk should be emitted. Because we must use the ABI mandated
2160 name, we must continue searching from the binfo where we
2161 found the most recent definition of the function, towards the
2162 primary binfo which first introduced the function into the
2163 vtable. If that enters a virtual base, we must use a vcall
2164 this-adjusting thunk. Bleah! */
2165 tree probe = first_defn;
2167 while ((probe = get_primary_binfo (probe))
2168 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2169 if (BINFO_VIRTUAL_P (probe))
2170 virtual_base = probe;
2173 /* Even if we find a virtual base, the correct delta is
2174 between the overrider and the binfo we're building a vtable
2176 goto virtual_covariant;
2179 /* Compute the constant adjustment to the `this' pointer. The
2180 `this' pointer, when this function is called, will point at BINFO
2181 (or one of its primary bases, which are at the same offset). */
2183 /* The `this' pointer needs to be adjusted from the declaration to
2184 the nearest virtual base. */
2185 delta = size_diffop (convert (ssizetype, BINFO_OFFSET (virtual_base)),
2186 convert (ssizetype, BINFO_OFFSET (first_defn)));
2188 /* If the nearest definition is in a lost primary, we don't need an
2189 entry in our vtable. Except possibly in a constructor vtable,
2190 if we happen to get our primary back. In that case, the offset
2191 will be zero, as it will be a primary base. */
2192 delta = size_zero_node;
2194 /* The `this' pointer needs to be adjusted from pointing to
2195 BINFO to pointing at the base where the final overrider
2198 delta = size_diffop (convert (ssizetype,
2199 BINFO_OFFSET (TREE_VALUE (overrider))),
2200 convert (ssizetype, BINFO_OFFSET (binfo)));
2202 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2205 BV_VCALL_INDEX (*virtuals)
2206 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2208 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2211 /* Called from modify_all_vtables via dfs_walk. */
2214 dfs_modify_vtables (tree binfo, void* data)
2216 tree t = (tree) data;
2221 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2222 /* A base without a vtable needs no modification, and its bases
2223 are uninteresting. */
2224 return dfs_skip_bases;
2226 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2227 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2228 /* Don't do the primary vtable, if it's new. */
2231 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2232 /* There's no need to modify the vtable for a non-virtual primary
2233 base; we're not going to use that vtable anyhow. We do still
2234 need to do this for virtual primary bases, as they could become
2235 non-primary in a construction vtable. */
2238 make_new_vtable (t, binfo);
2240 /* Now, go through each of the virtual functions in the virtual
2241 function table for BINFO. Find the final overrider, and update
2242 the BINFO_VIRTUALS list appropriately. */
2243 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2244 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2246 ix++, virtuals = TREE_CHAIN (virtuals),
2247 old_virtuals = TREE_CHAIN (old_virtuals))
2248 update_vtable_entry_for_fn (t,
2250 BV_FN (old_virtuals),
2256 /* Update all of the primary and secondary vtables for T. Create new
2257 vtables as required, and initialize their RTTI information. Each
2258 of the functions in VIRTUALS is declared in T and may override a
2259 virtual function from a base class; find and modify the appropriate
2260 entries to point to the overriding functions. Returns a list, in
2261 declaration order, of the virtual functions that are declared in T,
2262 but do not appear in the primary base class vtable, and which
2263 should therefore be appended to the end of the vtable for T. */
2266 modify_all_vtables (tree t, tree virtuals)
2268 tree binfo = TYPE_BINFO (t);
2271 /* Update all of the vtables. */
2272 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2274 /* Add virtual functions not already in our primary vtable. These
2275 will be both those introduced by this class, and those overridden
2276 from secondary bases. It does not include virtuals merely
2277 inherited from secondary bases. */
2278 for (fnsp = &virtuals; *fnsp; )
2280 tree fn = TREE_VALUE (*fnsp);
2282 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2283 || DECL_VINDEX (fn) == error_mark_node)
2285 /* We don't need to adjust the `this' pointer when
2286 calling this function. */
2287 BV_DELTA (*fnsp) = integer_zero_node;
2288 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2290 /* This is a function not already in our vtable. Keep it. */
2291 fnsp = &TREE_CHAIN (*fnsp);
2294 /* We've already got an entry for this function. Skip it. */
2295 *fnsp = TREE_CHAIN (*fnsp);
2301 /* Get the base virtual function declarations in T that have the
2305 get_basefndecls (tree name, tree t)
2308 tree base_fndecls = NULL_TREE;
2309 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2312 /* Find virtual functions in T with the indicated NAME. */
2313 i = lookup_fnfields_1 (t, name);
2315 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2317 methods = OVL_NEXT (methods))
2319 tree method = OVL_CURRENT (methods);
2321 if (TREE_CODE (method) == FUNCTION_DECL
2322 && DECL_VINDEX (method))
2323 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2327 return base_fndecls;
2329 for (i = 0; i < n_baseclasses; i++)
2331 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2332 base_fndecls = chainon (get_basefndecls (name, basetype),
2336 return base_fndecls;
2339 /* If this declaration supersedes the declaration of
2340 a method declared virtual in the base class, then
2341 mark this field as being virtual as well. */
2344 check_for_override (tree decl, tree ctype)
2346 if (TREE_CODE (decl) == TEMPLATE_DECL)
2347 /* In [temp.mem] we have:
2349 A specialization of a member function template does not
2350 override a virtual function from a base class. */
2352 if ((DECL_DESTRUCTOR_P (decl)
2353 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2354 || DECL_CONV_FN_P (decl))
2355 && look_for_overrides (ctype, decl)
2356 && !DECL_STATIC_FUNCTION_P (decl))
2357 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2358 the error_mark_node so that we know it is an overriding
2360 DECL_VINDEX (decl) = decl;
2362 if (DECL_VIRTUAL_P (decl))
2364 if (!DECL_VINDEX (decl))
2365 DECL_VINDEX (decl) = error_mark_node;
2366 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2370 /* Warn about hidden virtual functions that are not overridden in t.
2371 We know that constructors and destructors don't apply. */
2374 warn_hidden (tree t)
2376 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2380 /* We go through each separately named virtual function. */
2381 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2382 VEC_iterate (tree, method_vec, i, fns);
2393 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2394 have the same name. Figure out what name that is. */
2395 name = DECL_NAME (OVL_CURRENT (fns));
2396 /* There are no possibly hidden functions yet. */
2397 base_fndecls = NULL_TREE;
2398 /* Iterate through all of the base classes looking for possibly
2399 hidden functions. */
2400 for (binfo = TYPE_BINFO (t), j = 0;
2401 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2403 tree basetype = BINFO_TYPE (base_binfo);
2404 base_fndecls = chainon (get_basefndecls (name, basetype),
2408 /* If there are no functions to hide, continue. */
2412 /* Remove any overridden functions. */
2413 for (fn = fns; fn; fn = OVL_NEXT (fn))
2415 fndecl = OVL_CURRENT (fn);
2416 if (DECL_VINDEX (fndecl))
2418 tree *prev = &base_fndecls;
2421 /* If the method from the base class has the same
2422 signature as the method from the derived class, it
2423 has been overridden. */
2424 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2425 *prev = TREE_CHAIN (*prev);
2427 prev = &TREE_CHAIN (*prev);
2431 /* Now give a warning for all base functions without overriders,
2432 as they are hidden. */
2433 while (base_fndecls)
2435 /* Here we know it is a hider, and no overrider exists. */
2436 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2437 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2438 base_fndecls = TREE_CHAIN (base_fndecls);
2443 /* Check for things that are invalid. There are probably plenty of other
2444 things we should check for also. */
2447 finish_struct_anon (tree t)
2451 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2453 if (TREE_STATIC (field))
2455 if (TREE_CODE (field) != FIELD_DECL)
2458 if (DECL_NAME (field) == NULL_TREE
2459 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2461 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2462 for (; elt; elt = TREE_CHAIN (elt))
2464 /* We're generally only interested in entities the user
2465 declared, but we also find nested classes by noticing
2466 the TYPE_DECL that we create implicitly. You're
2467 allowed to put one anonymous union inside another,
2468 though, so we explicitly tolerate that. We use
2469 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2470 we also allow unnamed types used for defining fields. */
2471 if (DECL_ARTIFICIAL (elt)
2472 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2473 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2476 if (TREE_CODE (elt) != FIELD_DECL)
2478 pedwarn ("%q+#D invalid; an anonymous union can "
2479 "only have non-static data members", elt);
2483 if (TREE_PRIVATE (elt))
2484 pedwarn ("private member %q+#D in anonymous union", elt);
2485 else if (TREE_PROTECTED (elt))
2486 pedwarn ("protected member %q+#D in anonymous union", elt);
2488 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2489 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2495 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2496 will be used later during class template instantiation.
2497 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2498 a non-static member data (FIELD_DECL), a member function
2499 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2500 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2501 When FRIEND_P is nonzero, T is either a friend class
2502 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2503 (FUNCTION_DECL, TEMPLATE_DECL). */
2506 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2508 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2509 if (CLASSTYPE_TEMPLATE_INFO (type))
2510 CLASSTYPE_DECL_LIST (type)
2511 = tree_cons (friend_p ? NULL_TREE : type,
2512 t, CLASSTYPE_DECL_LIST (type));
2515 /* Create default constructors, assignment operators, and so forth for
2516 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2517 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2518 the class cannot have a default constructor, copy constructor
2519 taking a const reference argument, or an assignment operator taking
2520 a const reference, respectively. */
2523 add_implicitly_declared_members (tree t,
2524 int cant_have_const_cctor,
2525 int cant_have_const_assignment)
2528 if (!CLASSTYPE_DESTRUCTORS (t))
2530 /* In general, we create destructors lazily. */
2531 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2532 /* However, if the implicit destructor is non-trivial
2533 destructor, we sometimes have to create it at this point. */
2534 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2538 if (TYPE_FOR_JAVA (t))
2539 /* If this a Java class, any non-trivial destructor is
2540 invalid, even if compiler-generated. Therefore, if the
2541 destructor is non-trivial we create it now. */
2549 /* If the implicit destructor will be virtual, then we must
2550 generate it now because (unfortunately) we do not
2551 generate virtual tables lazily. */
2552 binfo = TYPE_BINFO (t);
2553 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2558 base_type = BINFO_TYPE (base_binfo);
2559 dtor = CLASSTYPE_DESTRUCTORS (base_type);
2560 if (dtor && DECL_VIRTUAL_P (dtor))
2568 /* If we can't get away with being lazy, generate the destructor
2571 lazily_declare_fn (sfk_destructor, t);
2575 /* Default constructor. */
2576 if (! TYPE_HAS_CONSTRUCTOR (t))
2578 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2579 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2582 /* Copy constructor. */
2583 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2585 TYPE_HAS_INIT_REF (t) = 1;
2586 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2587 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2588 TYPE_HAS_CONSTRUCTOR (t) = 1;
2591 /* If there is no assignment operator, one will be created if and
2592 when it is needed. For now, just record whether or not the type
2593 of the parameter to the assignment operator will be a const or
2594 non-const reference. */
2595 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2597 TYPE_HAS_ASSIGN_REF (t) = 1;
2598 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2599 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2603 /* Subroutine of finish_struct_1. Recursively count the number of fields
2604 in TYPE, including anonymous union members. */
2607 count_fields (tree fields)
2611 for (x = fields; x; x = TREE_CHAIN (x))
2613 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2614 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2621 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2622 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2625 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2628 for (x = fields; x; x = TREE_CHAIN (x))
2630 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2631 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2633 field_vec->elts[idx++] = x;
2638 /* FIELD is a bit-field. We are finishing the processing for its
2639 enclosing type. Issue any appropriate messages and set appropriate
2643 check_bitfield_decl (tree field)
2645 tree type = TREE_TYPE (field);
2648 /* Extract the declared width of the bitfield, which has been
2649 temporarily stashed in DECL_INITIAL. */
2650 w = DECL_INITIAL (field);
2651 gcc_assert (w != NULL_TREE);
2652 /* Remove the bit-field width indicator so that the rest of the
2653 compiler does not treat that value as an initializer. */
2654 DECL_INITIAL (field) = NULL_TREE;
2656 /* Detect invalid bit-field type. */
2657 if (!INTEGRAL_TYPE_P (type))
2659 error ("bit-field %q+#D with non-integral type", field);
2660 TREE_TYPE (field) = error_mark_node;
2661 w = error_mark_node;
2665 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2668 /* detect invalid field size. */
2669 w = integral_constant_value (w);
2671 if (TREE_CODE (w) != INTEGER_CST)
2673 error ("bit-field %q+D width not an integer constant", field);
2674 w = error_mark_node;
2676 else if (tree_int_cst_sgn (w) < 0)
2678 error ("negative width in bit-field %q+D", field);
2679 w = error_mark_node;
2681 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2683 error ("zero width for bit-field %q+D", field);
2684 w = error_mark_node;
2686 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2687 && TREE_CODE (type) != ENUMERAL_TYPE
2688 && TREE_CODE (type) != BOOLEAN_TYPE)
2689 warning (0, "width of %q+D exceeds its type", field);
2690 else if (TREE_CODE (type) == ENUMERAL_TYPE
2691 && (0 > compare_tree_int (w,
2692 min_precision (TYPE_MIN_VALUE (type),
2693 TYPE_UNSIGNED (type)))
2694 || 0 > compare_tree_int (w,
2696 (TYPE_MAX_VALUE (type),
2697 TYPE_UNSIGNED (type)))))
2698 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2701 if (w != error_mark_node)
2703 DECL_SIZE (field) = convert (bitsizetype, w);
2704 DECL_BIT_FIELD (field) = 1;
2708 /* Non-bit-fields are aligned for their type. */
2709 DECL_BIT_FIELD (field) = 0;
2710 CLEAR_DECL_C_BIT_FIELD (field);
2714 /* FIELD is a non bit-field. We are finishing the processing for its
2715 enclosing type T. Issue any appropriate messages and set appropriate
2719 check_field_decl (tree field,
2721 int* cant_have_const_ctor,
2722 int* no_const_asn_ref,
2723 int* any_default_members)
2725 tree type = strip_array_types (TREE_TYPE (field));
2727 /* An anonymous union cannot contain any fields which would change
2728 the settings of CANT_HAVE_CONST_CTOR and friends. */
2729 if (ANON_UNION_TYPE_P (type))
2731 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2732 structs. So, we recurse through their fields here. */
2733 else if (ANON_AGGR_TYPE_P (type))
2737 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2738 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2739 check_field_decl (fields, t, cant_have_const_ctor,
2740 no_const_asn_ref, any_default_members);
2742 /* Check members with class type for constructors, destructors,
2744 else if (CLASS_TYPE_P (type))
2746 /* Never let anything with uninheritable virtuals
2747 make it through without complaint. */
2748 abstract_virtuals_error (field, type);
2750 if (TREE_CODE (t) == UNION_TYPE)
2752 if (TYPE_NEEDS_CONSTRUCTING (type))
2753 error ("member %q+#D with constructor not allowed in union",
2755 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2756 error ("member %q+#D with destructor not allowed in union", field);
2757 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2758 error ("member %q+#D with copy assignment operator not allowed in union",
2763 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2764 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2765 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2766 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2767 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2768 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (type);
2771 if (!TYPE_HAS_CONST_INIT_REF (type))
2772 *cant_have_const_ctor = 1;
2774 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2775 *no_const_asn_ref = 1;
2777 if (DECL_INITIAL (field) != NULL_TREE)
2779 /* `build_class_init_list' does not recognize
2781 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2782 error ("multiple fields in union %qT initialized", t);
2783 *any_default_members = 1;
2787 /* Check the data members (both static and non-static), class-scoped
2788 typedefs, etc., appearing in the declaration of T. Issue
2789 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2790 declaration order) of access declarations; each TREE_VALUE in this
2791 list is a USING_DECL.
2793 In addition, set the following flags:
2796 The class is empty, i.e., contains no non-static data members.
2798 CANT_HAVE_CONST_CTOR_P
2799 This class cannot have an implicitly generated copy constructor
2800 taking a const reference.
2802 CANT_HAVE_CONST_ASN_REF
2803 This class cannot have an implicitly generated assignment
2804 operator taking a const reference.
2806 All of these flags should be initialized before calling this
2809 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2810 fields can be added by adding to this chain. */
2813 check_field_decls (tree t, tree *access_decls,
2814 int *cant_have_const_ctor_p,
2815 int *no_const_asn_ref_p)
2820 int any_default_members;
2823 /* Assume there are no access declarations. */
2824 *access_decls = NULL_TREE;
2825 /* Assume this class has no pointer members. */
2826 has_pointers = false;
2827 /* Assume none of the members of this class have default
2829 any_default_members = 0;
2831 for (field = &TYPE_FIELDS (t); *field; field = next)
2834 tree type = TREE_TYPE (x);
2836 next = &TREE_CHAIN (x);
2838 if (TREE_CODE (x) == USING_DECL)
2840 /* Prune the access declaration from the list of fields. */
2841 *field = TREE_CHAIN (x);
2843 /* Save the access declarations for our caller. */
2844 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2846 /* Since we've reset *FIELD there's no reason to skip to the
2852 if (TREE_CODE (x) == TYPE_DECL
2853 || TREE_CODE (x) == TEMPLATE_DECL)
2856 /* If we've gotten this far, it's a data member, possibly static,
2857 or an enumerator. */
2858 DECL_CONTEXT (x) = t;
2860 /* When this goes into scope, it will be a non-local reference. */
2861 DECL_NONLOCAL (x) = 1;
2863 if (TREE_CODE (t) == UNION_TYPE)
2867 If a union contains a static data member, or a member of
2868 reference type, the program is ill-formed. */
2869 if (TREE_CODE (x) == VAR_DECL)
2871 error ("%q+D may not be static because it is a member of a union", x);
2874 if (TREE_CODE (type) == REFERENCE_TYPE)
2876 error ("%q+D may not have reference type %qT because"
2877 " it is a member of a union",
2883 /* Perform error checking that did not get done in
2885 if (TREE_CODE (type) == FUNCTION_TYPE)
2887 error ("field %q+D invalidly declared function type", x);
2888 type = build_pointer_type (type);
2889 TREE_TYPE (x) = type;
2891 else if (TREE_CODE (type) == METHOD_TYPE)
2893 error ("field %q+D invalidly declared method type", x);
2894 type = build_pointer_type (type);
2895 TREE_TYPE (x) = type;
2898 if (type == error_mark_node)
2901 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
2904 /* Now it can only be a FIELD_DECL. */
2906 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
2907 CLASSTYPE_NON_AGGREGATE (t) = 1;
2909 /* If this is of reference type, check if it needs an init.
2910 Also do a little ANSI jig if necessary. */
2911 if (TREE_CODE (type) == REFERENCE_TYPE)
2913 CLASSTYPE_NON_POD_P (t) = 1;
2914 if (DECL_INITIAL (x) == NULL_TREE)
2915 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2917 /* ARM $12.6.2: [A member initializer list] (or, for an
2918 aggregate, initialization by a brace-enclosed list) is the
2919 only way to initialize nonstatic const and reference
2921 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2923 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
2925 warning (OPT_Wextra, "non-static reference %q+#D in class without a constructor", x);
2928 type = strip_array_types (type);
2930 if (TYPE_PACKED (t))
2932 if (!pod_type_p (type) && !TYPE_PACKED (type))
2936 "ignoring packed attribute because of unpacked non-POD field %q+#D",
2940 else if (TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
2941 DECL_PACKED (x) = 1;
2944 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
2945 /* We don't treat zero-width bitfields as making a class
2950 /* The class is non-empty. */
2951 CLASSTYPE_EMPTY_P (t) = 0;
2952 /* The class is not even nearly empty. */
2953 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
2954 /* If one of the data members contains an empty class,
2956 if (CLASS_TYPE_P (type)
2957 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
2958 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
2961 /* This is used by -Weffc++ (see below). Warn only for pointers
2962 to members which might hold dynamic memory. So do not warn
2963 for pointers to functions or pointers to members. */
2964 if (TYPE_PTR_P (type)
2965 && !TYPE_PTRFN_P (type)
2966 && !TYPE_PTR_TO_MEMBER_P (type))
2967 has_pointers = true;
2969 if (CLASS_TYPE_P (type))
2971 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
2972 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2973 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
2974 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
2977 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
2978 CLASSTYPE_HAS_MUTABLE (t) = 1;
2980 if (! pod_type_p (type))
2981 /* DR 148 now allows pointers to members (which are POD themselves),
2982 to be allowed in POD structs. */
2983 CLASSTYPE_NON_POD_P (t) = 1;
2985 if (! zero_init_p (type))
2986 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
2988 /* If any field is const, the structure type is pseudo-const. */
2989 if (CP_TYPE_CONST_P (type))
2991 C_TYPE_FIELDS_READONLY (t) = 1;
2992 if (DECL_INITIAL (x) == NULL_TREE)
2993 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
2995 /* ARM $12.6.2: [A member initializer list] (or, for an
2996 aggregate, initialization by a brace-enclosed list) is the
2997 only way to initialize nonstatic const and reference
2999 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3001 if (! TYPE_HAS_CONSTRUCTOR (t) && CLASSTYPE_NON_AGGREGATE (t)
3003 warning (OPT_Wextra, "non-static const member %q+#D in class without a constructor", x);
3005 /* A field that is pseudo-const makes the structure likewise. */
3006 else if (CLASS_TYPE_P (type))
3008 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3009 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3010 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3011 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3014 /* Core issue 80: A nonstatic data member is required to have a
3015 different name from the class iff the class has a
3016 user-defined constructor. */
3017 if (constructor_name_p (DECL_NAME (x), t) && TYPE_HAS_CONSTRUCTOR (t))
3018 pedwarn ("field %q+#D with same name as class", x);
3020 /* We set DECL_C_BIT_FIELD in grokbitfield.
3021 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3022 if (DECL_C_BIT_FIELD (x))
3023 check_bitfield_decl (x);
3025 check_field_decl (x, t,
3026 cant_have_const_ctor_p,
3028 &any_default_members);
3031 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3032 it should also define a copy constructor and an assignment operator to
3033 implement the correct copy semantic (deep vs shallow, etc.). As it is
3034 not feasible to check whether the constructors do allocate dynamic memory
3035 and store it within members, we approximate the warning like this:
3037 -- Warn only if there are members which are pointers
3038 -- Warn only if there is a non-trivial constructor (otherwise,
3039 there cannot be memory allocated).
3040 -- Warn only if there is a non-trivial destructor. We assume that the
3041 user at least implemented the cleanup correctly, and a destructor
3042 is needed to free dynamic memory.
3044 This seems enough for practical purposes. */
3047 && TYPE_HAS_CONSTRUCTOR (t)
3048 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3049 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3051 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3053 if (! TYPE_HAS_INIT_REF (t))
3055 warning (OPT_Weffc__,
3056 " but does not override %<%T(const %T&)%>", t, t);
3057 if (!TYPE_HAS_ASSIGN_REF (t))
3058 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3060 else if (! TYPE_HAS_ASSIGN_REF (t))
3061 warning (OPT_Weffc__,
3062 " but does not override %<operator=(const %T&)%>", t);
3065 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3067 TYPE_PACKED (t) = 0;
3069 /* Check anonymous struct/anonymous union fields. */
3070 finish_struct_anon (t);
3072 /* We've built up the list of access declarations in reverse order.
3074 *access_decls = nreverse (*access_decls);
3077 /* If TYPE is an empty class type, records its OFFSET in the table of
3081 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3085 if (!is_empty_class (type))
3088 /* Record the location of this empty object in OFFSETS. */
3089 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3091 n = splay_tree_insert (offsets,
3092 (splay_tree_key) offset,
3093 (splay_tree_value) NULL_TREE);
3094 n->value = ((splay_tree_value)
3095 tree_cons (NULL_TREE,
3102 /* Returns nonzero if TYPE is an empty class type and there is
3103 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3106 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3111 if (!is_empty_class (type))
3114 /* Record the location of this empty object in OFFSETS. */
3115 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3119 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3120 if (same_type_p (TREE_VALUE (t), type))
3126 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3127 F for every subobject, passing it the type, offset, and table of
3128 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3131 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3132 than MAX_OFFSET will not be walked.
3134 If F returns a nonzero value, the traversal ceases, and that value
3135 is returned. Otherwise, returns zero. */
3138 walk_subobject_offsets (tree type,
3139 subobject_offset_fn f,
3146 tree type_binfo = NULL_TREE;
3148 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3150 if (max_offset && INT_CST_LT (max_offset, offset))
3153 if (type == error_mark_node)
3158 if (abi_version_at_least (2))
3160 type = BINFO_TYPE (type);
3163 if (CLASS_TYPE_P (type))
3169 /* Avoid recursing into objects that are not interesting. */
3170 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3173 /* Record the location of TYPE. */
3174 r = (*f) (type, offset, offsets);
3178 /* Iterate through the direct base classes of TYPE. */
3180 type_binfo = TYPE_BINFO (type);
3181 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3185 if (abi_version_at_least (2)
3186 && BINFO_VIRTUAL_P (binfo))
3190 && BINFO_VIRTUAL_P (binfo)
3191 && !BINFO_PRIMARY_P (binfo))
3194 if (!abi_version_at_least (2))
3195 binfo_offset = size_binop (PLUS_EXPR,
3197 BINFO_OFFSET (binfo));
3201 /* We cannot rely on BINFO_OFFSET being set for the base
3202 class yet, but the offsets for direct non-virtual
3203 bases can be calculated by going back to the TYPE. */
3204 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3205 binfo_offset = size_binop (PLUS_EXPR,
3207 BINFO_OFFSET (orig_binfo));
3210 r = walk_subobject_offsets (binfo,
3215 (abi_version_at_least (2)
3216 ? /*vbases_p=*/0 : vbases_p));
3221 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3224 VEC(tree,gc) *vbases;
3226 /* Iterate through the virtual base classes of TYPE. In G++
3227 3.2, we included virtual bases in the direct base class
3228 loop above, which results in incorrect results; the
3229 correct offsets for virtual bases are only known when
3230 working with the most derived type. */
3232 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3233 VEC_iterate (tree, vbases, ix, binfo); ix++)
3235 r = walk_subobject_offsets (binfo,
3237 size_binop (PLUS_EXPR,
3239 BINFO_OFFSET (binfo)),
3248 /* We still have to walk the primary base, if it is
3249 virtual. (If it is non-virtual, then it was walked
3251 tree vbase = get_primary_binfo (type_binfo);
3253 if (vbase && BINFO_VIRTUAL_P (vbase)
3254 && BINFO_PRIMARY_P (vbase)
3255 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3257 r = (walk_subobject_offsets
3259 offsets, max_offset, /*vbases_p=*/0));
3266 /* Iterate through the fields of TYPE. */
3267 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3268 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3272 if (abi_version_at_least (2))
3273 field_offset = byte_position (field);
3275 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3276 field_offset = DECL_FIELD_OFFSET (field);
3278 r = walk_subobject_offsets (TREE_TYPE (field),
3280 size_binop (PLUS_EXPR,
3290 else if (TREE_CODE (type) == ARRAY_TYPE)
3292 tree element_type = strip_array_types (type);
3293 tree domain = TYPE_DOMAIN (type);
3296 /* Avoid recursing into objects that are not interesting. */
3297 if (!CLASS_TYPE_P (element_type)
3298 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3301 /* Step through each of the elements in the array. */
3302 for (index = size_zero_node;
3303 /* G++ 3.2 had an off-by-one error here. */
3304 (abi_version_at_least (2)
3305 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3306 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3307 index = size_binop (PLUS_EXPR, index, size_one_node))
3309 r = walk_subobject_offsets (TREE_TYPE (type),
3317 offset = size_binop (PLUS_EXPR, offset,
3318 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3319 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3320 there's no point in iterating through the remaining
3321 elements of the array. */
3322 if (max_offset && INT_CST_LT (max_offset, offset))
3330 /* Record all of the empty subobjects of TYPE (either a type or a
3331 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3332 is being placed at OFFSET; otherwise, it is a base class that is
3333 being placed at OFFSET. */
3336 record_subobject_offsets (tree type,
3339 bool is_data_member)
3342 /* If recording subobjects for a non-static data member or a
3343 non-empty base class , we do not need to record offsets beyond
3344 the size of the biggest empty class. Additional data members
3345 will go at the end of the class. Additional base classes will go
3346 either at offset zero (if empty, in which case they cannot
3347 overlap with offsets past the size of the biggest empty class) or
3348 at the end of the class.
3350 However, if we are placing an empty base class, then we must record
3351 all offsets, as either the empty class is at offset zero (where
3352 other empty classes might later be placed) or at the end of the
3353 class (where other objects might then be placed, so other empty
3354 subobjects might later overlap). */
3356 || !is_empty_class (BINFO_TYPE (type)))
3357 max_offset = sizeof_biggest_empty_class;
3359 max_offset = NULL_TREE;
3360 walk_subobject_offsets (type, record_subobject_offset, offset,
3361 offsets, max_offset, is_data_member);
3364 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3365 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3366 virtual bases of TYPE are examined. */
3369 layout_conflict_p (tree type,
3374 splay_tree_node max_node;
3376 /* Get the node in OFFSETS that indicates the maximum offset where
3377 an empty subobject is located. */
3378 max_node = splay_tree_max (offsets);
3379 /* If there aren't any empty subobjects, then there's no point in
3380 performing this check. */
3384 return walk_subobject_offsets (type, check_subobject_offset, offset,
3385 offsets, (tree) (max_node->key),
3389 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3390 non-static data member of the type indicated by RLI. BINFO is the
3391 binfo corresponding to the base subobject, OFFSETS maps offsets to
3392 types already located at those offsets. This function determines
3393 the position of the DECL. */
3396 layout_nonempty_base_or_field (record_layout_info rli,
3401 tree offset = NULL_TREE;
3407 /* For the purposes of determining layout conflicts, we want to
3408 use the class type of BINFO; TREE_TYPE (DECL) will be the
3409 CLASSTYPE_AS_BASE version, which does not contain entries for
3410 zero-sized bases. */
3411 type = TREE_TYPE (binfo);
3416 type = TREE_TYPE (decl);
3420 /* Try to place the field. It may take more than one try if we have
3421 a hard time placing the field without putting two objects of the
3422 same type at the same address. */
3425 struct record_layout_info_s old_rli = *rli;
3427 /* Place this field. */
3428 place_field (rli, decl);
3429 offset = byte_position (decl);
3431 /* We have to check to see whether or not there is already
3432 something of the same type at the offset we're about to use.
3433 For example, consider:
3436 struct T : public S { int i; };
3437 struct U : public S, public T {};
3439 Here, we put S at offset zero in U. Then, we can't put T at
3440 offset zero -- its S component would be at the same address
3441 as the S we already allocated. So, we have to skip ahead.
3442 Since all data members, including those whose type is an
3443 empty class, have nonzero size, any overlap can happen only
3444 with a direct or indirect base-class -- it can't happen with
3446 /* In a union, overlap is permitted; all members are placed at
3448 if (TREE_CODE (rli->t) == UNION_TYPE)
3450 /* G++ 3.2 did not check for overlaps when placing a non-empty
3452 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3454 if (layout_conflict_p (field_p ? type : binfo, offset,
3457 /* Strip off the size allocated to this field. That puts us
3458 at the first place we could have put the field with
3459 proper alignment. */
3462 /* Bump up by the alignment required for the type. */
3464 = size_binop (PLUS_EXPR, rli->bitpos,
3466 ? CLASSTYPE_ALIGN (type)
3467 : TYPE_ALIGN (type)));
3468 normalize_rli (rli);
3471 /* There was no conflict. We're done laying out this field. */
3475 /* Now that we know where it will be placed, update its
3477 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3478 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3479 this point because their BINFO_OFFSET is copied from another
3480 hierarchy. Therefore, we may not need to add the entire
3482 propagate_binfo_offsets (binfo,
3483 size_diffop (convert (ssizetype, offset),
3485 BINFO_OFFSET (binfo))));
3488 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3491 empty_base_at_nonzero_offset_p (tree type,
3493 splay_tree offsets ATTRIBUTE_UNUSED)
3495 return is_empty_class (type) && !integer_zerop (offset);
3498 /* Layout the empty base BINFO. EOC indicates the byte currently just
3499 past the end of the class, and should be correctly aligned for a
3500 class of the type indicated by BINFO; OFFSETS gives the offsets of
3501 the empty bases allocated so far. T is the most derived
3502 type. Return nonzero iff we added it at the end. */
3505 layout_empty_base (tree binfo, tree eoc, splay_tree offsets)
3508 tree basetype = BINFO_TYPE (binfo);
3511 /* This routine should only be used for empty classes. */
3512 gcc_assert (is_empty_class (basetype));
3513 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3515 if (!integer_zerop (BINFO_OFFSET (binfo)))
3517 if (abi_version_at_least (2))
3518 propagate_binfo_offsets
3519 (binfo, size_diffop (size_zero_node, BINFO_OFFSET (binfo)));
3522 "offset of empty base %qT may not be ABI-compliant and may"
3523 "change in a future version of GCC",
3524 BINFO_TYPE (binfo));
3527 /* This is an empty base class. We first try to put it at offset
3529 if (layout_conflict_p (binfo,
3530 BINFO_OFFSET (binfo),
3534 /* That didn't work. Now, we move forward from the next
3535 available spot in the class. */
3537 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3540 if (!layout_conflict_p (binfo,
3541 BINFO_OFFSET (binfo),
3544 /* We finally found a spot where there's no overlap. */
3547 /* There's overlap here, too. Bump along to the next spot. */
3548 propagate_binfo_offsets (binfo, alignment);
3554 /* Layout the base given by BINFO in the class indicated by RLI.
3555 *BASE_ALIGN is a running maximum of the alignments of
3556 any base class. OFFSETS gives the location of empty base
3557 subobjects. T is the most derived type. Return nonzero if the new
3558 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3559 *NEXT_FIELD, unless BINFO is for an empty base class.
3561 Returns the location at which the next field should be inserted. */
3564 build_base_field (record_layout_info rli, tree binfo,
3565 splay_tree offsets, tree *next_field)
3568 tree basetype = BINFO_TYPE (binfo);
3570 if (!COMPLETE_TYPE_P (basetype))
3571 /* This error is now reported in xref_tag, thus giving better
3572 location information. */
3575 /* Place the base class. */
3576 if (!is_empty_class (basetype))
3580 /* The containing class is non-empty because it has a non-empty
3582 CLASSTYPE_EMPTY_P (t) = 0;
3584 /* Create the FIELD_DECL. */
3585 decl = build_decl (FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3586 DECL_ARTIFICIAL (decl) = 1;
3587 DECL_IGNORED_P (decl) = 1;
3588 DECL_FIELD_CONTEXT (decl) = t;
3589 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3590 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3591 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3592 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3593 DECL_MODE (decl) = TYPE_MODE (basetype);
3594 DECL_FIELD_IS_BASE (decl) = 1;
3596 /* Try to place the field. It may take more than one try if we
3597 have a hard time placing the field without putting two
3598 objects of the same type at the same address. */
3599 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3600 /* Add the new FIELD_DECL to the list of fields for T. */
3601 TREE_CHAIN (decl) = *next_field;
3603 next_field = &TREE_CHAIN (decl);
3610 /* On some platforms (ARM), even empty classes will not be
3612 eoc = round_up (rli_size_unit_so_far (rli),
3613 CLASSTYPE_ALIGN_UNIT (basetype));
3614 atend = layout_empty_base (binfo, eoc, offsets);
3615 /* A nearly-empty class "has no proper base class that is empty,
3616 not morally virtual, and at an offset other than zero." */
3617 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3620 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3621 /* The check above (used in G++ 3.2) is insufficient because
3622 an empty class placed at offset zero might itself have an
3623 empty base at a nonzero offset. */
3624 else if (walk_subobject_offsets (basetype,
3625 empty_base_at_nonzero_offset_p,
3628 /*max_offset=*/NULL_TREE,
3631 if (abi_version_at_least (2))
3632 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3635 "class %qT will be considered nearly empty in a "
3636 "future version of GCC", t);
3640 /* We do not create a FIELD_DECL for empty base classes because
3641 it might overlap some other field. We want to be able to
3642 create CONSTRUCTORs for the class by iterating over the
3643 FIELD_DECLs, and the back end does not handle overlapping
3646 /* An empty virtual base causes a class to be non-empty
3647 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3648 here because that was already done when the virtual table
3649 pointer was created. */
3652 /* Record the offsets of BINFO and its base subobjects. */
3653 record_subobject_offsets (binfo,
3654 BINFO_OFFSET (binfo),
3656 /*is_data_member=*/false);
3661 /* Layout all of the non-virtual base classes. Record empty
3662 subobjects in OFFSETS. T is the most derived type. Return nonzero
3663 if the type cannot be nearly empty. The fields created
3664 corresponding to the base classes will be inserted at
3668 build_base_fields (record_layout_info rli,
3669 splay_tree offsets, tree *next_field)
3671 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3674 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3677 /* The primary base class is always allocated first. */
3678 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3679 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3680 offsets, next_field);
3682 /* Now allocate the rest of the bases. */
3683 for (i = 0; i < n_baseclasses; ++i)
3687 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3689 /* The primary base was already allocated above, so we don't
3690 need to allocate it again here. */
3691 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3694 /* Virtual bases are added at the end (a primary virtual base
3695 will have already been added). */
3696 if (BINFO_VIRTUAL_P (base_binfo))
3699 next_field = build_base_field (rli, base_binfo,
3700 offsets, next_field);
3704 /* Go through the TYPE_METHODS of T issuing any appropriate
3705 diagnostics, figuring out which methods override which other
3706 methods, and so forth. */
3709 check_methods (tree t)
3713 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3715 check_for_override (x, t);
3716 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3717 error ("initializer specified for non-virtual method %q+D", x);
3718 /* The name of the field is the original field name
3719 Save this in auxiliary field for later overloading. */
3720 if (DECL_VINDEX (x))
3722 TYPE_POLYMORPHIC_P (t) = 1;
3723 if (DECL_PURE_VIRTUAL_P (x))
3724 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3726 /* All user-declared destructors are non-trivial. */
3727 if (DECL_DESTRUCTOR_P (x))
3728 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3732 /* FN is a constructor or destructor. Clone the declaration to create
3733 a specialized in-charge or not-in-charge version, as indicated by
3737 build_clone (tree fn, tree name)
3742 /* Copy the function. */
3743 clone = copy_decl (fn);
3744 /* Remember where this function came from. */
3745 DECL_CLONED_FUNCTION (clone) = fn;
3746 DECL_ABSTRACT_ORIGIN (clone) = fn;
3747 /* Reset the function name. */
3748 DECL_NAME (clone) = name;
3749 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3750 /* There's no pending inline data for this function. */
3751 DECL_PENDING_INLINE_INFO (clone) = NULL;
3752 DECL_PENDING_INLINE_P (clone) = 0;
3753 /* And it hasn't yet been deferred. */
3754 DECL_DEFERRED_FN (clone) = 0;
3756 /* The base-class destructor is not virtual. */
3757 if (name == base_dtor_identifier)
3759 DECL_VIRTUAL_P (clone) = 0;
3760 if (TREE_CODE (clone) != TEMPLATE_DECL)
3761 DECL_VINDEX (clone) = NULL_TREE;
3764 /* If there was an in-charge parameter, drop it from the function
3766 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3772 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3773 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3774 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3775 /* Skip the `this' parameter. */
3776 parmtypes = TREE_CHAIN (parmtypes);
3777 /* Skip the in-charge parameter. */
3778 parmtypes = TREE_CHAIN (parmtypes);
3779 /* And the VTT parm, in a complete [cd]tor. */
3780 if (DECL_HAS_VTT_PARM_P (fn)
3781 && ! DECL_NEEDS_VTT_PARM_P (clone))
3782 parmtypes = TREE_CHAIN (parmtypes);
3783 /* If this is subobject constructor or destructor, add the vtt
3786 = build_method_type_directly (basetype,
3787 TREE_TYPE (TREE_TYPE (clone)),
3790 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3793 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3794 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3797 /* Copy the function parameters. But, DECL_ARGUMENTS on a TEMPLATE_DECL
3798 aren't function parameters; those are the template parameters. */
3799 if (TREE_CODE (clone) != TEMPLATE_DECL)
3801 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3802 /* Remove the in-charge parameter. */
3803 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3805 TREE_CHAIN (DECL_ARGUMENTS (clone))
3806 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3807 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3809 /* And the VTT parm, in a complete [cd]tor. */
3810 if (DECL_HAS_VTT_PARM_P (fn))
3812 if (DECL_NEEDS_VTT_PARM_P (clone))
3813 DECL_HAS_VTT_PARM_P (clone) = 1;
3816 TREE_CHAIN (DECL_ARGUMENTS (clone))
3817 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3818 DECL_HAS_VTT_PARM_P (clone) = 0;
3822 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3824 DECL_CONTEXT (parms) = clone;
3825 cxx_dup_lang_specific_decl (parms);
3829 /* Create the RTL for this function. */
3830 SET_DECL_RTL (clone, NULL_RTX);
3831 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3833 /* Make it easy to find the CLONE given the FN. */
3834 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3835 TREE_CHAIN (fn) = clone;
3837 /* If this is a template, handle the DECL_TEMPLATE_RESULT as well. */
3838 if (TREE_CODE (clone) == TEMPLATE_DECL)
3842 DECL_TEMPLATE_RESULT (clone)
3843 = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3844 result = DECL_TEMPLATE_RESULT (clone);
3845 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3846 DECL_TI_TEMPLATE (result) = clone;
3849 note_decl_for_pch (clone);
3854 /* Produce declarations for all appropriate clones of FN. If
3855 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
3856 CLASTYPE_METHOD_VEC as well. */
3859 clone_function_decl (tree fn, int update_method_vec_p)
3863 /* Avoid inappropriate cloning. */
3865 && DECL_CLONED_FUNCTION (TREE_CHAIN (fn)))
3868 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
3870 /* For each constructor, we need two variants: an in-charge version
3871 and a not-in-charge version. */
3872 clone = build_clone (fn, complete_ctor_identifier);
3873 if (update_method_vec_p)
3874 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3875 clone = build_clone (fn, base_ctor_identifier);
3876 if (update_method_vec_p)
3877 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3881 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
3883 /* For each destructor, we need three variants: an in-charge
3884 version, a not-in-charge version, and an in-charge deleting
3885 version. We clone the deleting version first because that
3886 means it will go second on the TYPE_METHODS list -- and that
3887 corresponds to the correct layout order in the virtual
3890 For a non-virtual destructor, we do not build a deleting
3892 if (DECL_VIRTUAL_P (fn))
3894 clone = build_clone (fn, deleting_dtor_identifier);
3895 if (update_method_vec_p)
3896 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3898 clone = build_clone (fn, complete_dtor_identifier);
3899 if (update_method_vec_p)
3900 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3901 clone = build_clone (fn, base_dtor_identifier);
3902 if (update_method_vec_p)
3903 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3906 /* Note that this is an abstract function that is never emitted. */
3907 DECL_ABSTRACT (fn) = 1;
3910 /* DECL is an in charge constructor, which is being defined. This will
3911 have had an in class declaration, from whence clones were
3912 declared. An out-of-class definition can specify additional default
3913 arguments. As it is the clones that are involved in overload
3914 resolution, we must propagate the information from the DECL to its
3918 adjust_clone_args (tree decl)
3922 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION (clone);
3923 clone = TREE_CHAIN (clone))
3925 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
3926 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
3927 tree decl_parms, clone_parms;
3929 clone_parms = orig_clone_parms;
3931 /* Skip the 'this' parameter. */
3932 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
3933 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3935 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
3936 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3937 if (DECL_HAS_VTT_PARM_P (decl))
3938 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3940 clone_parms = orig_clone_parms;
3941 if (DECL_HAS_VTT_PARM_P (clone))
3942 clone_parms = TREE_CHAIN (clone_parms);
3944 for (decl_parms = orig_decl_parms; decl_parms;
3945 decl_parms = TREE_CHAIN (decl_parms),
3946 clone_parms = TREE_CHAIN (clone_parms))
3948 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
3949 TREE_TYPE (clone_parms)));
3951 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
3953 /* A default parameter has been added. Adjust the
3954 clone's parameters. */
3955 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3956 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3959 clone_parms = orig_decl_parms;
3961 if (DECL_HAS_VTT_PARM_P (clone))
3963 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
3964 TREE_VALUE (orig_clone_parms),
3966 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
3968 type = build_method_type_directly (basetype,
3969 TREE_TYPE (TREE_TYPE (clone)),
3972 type = build_exception_variant (type, exceptions);
3973 TREE_TYPE (clone) = type;
3975 clone_parms = NULL_TREE;
3979 gcc_assert (!clone_parms);
3983 /* For each of the constructors and destructors in T, create an
3984 in-charge and not-in-charge variant. */
3987 clone_constructors_and_destructors (tree t)
3991 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
3993 if (!CLASSTYPE_METHOD_VEC (t))
3996 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
3997 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
3998 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
3999 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4002 /* Remove all zero-width bit-fields from T. */
4005 remove_zero_width_bit_fields (tree t)
4009 fieldsp = &TYPE_FIELDS (t);
4012 if (TREE_CODE (*fieldsp) == FIELD_DECL
4013 && DECL_C_BIT_FIELD (*fieldsp)
4014 && DECL_INITIAL (*fieldsp))
4015 *fieldsp = TREE_CHAIN (*fieldsp);
4017 fieldsp = &TREE_CHAIN (*fieldsp);
4021 /* Returns TRUE iff we need a cookie when dynamically allocating an
4022 array whose elements have the indicated class TYPE. */
4025 type_requires_array_cookie (tree type)
4028 bool has_two_argument_delete_p = false;
4030 gcc_assert (CLASS_TYPE_P (type));
4032 /* If there's a non-trivial destructor, we need a cookie. In order
4033 to iterate through the array calling the destructor for each
4034 element, we'll have to know how many elements there are. */
4035 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4038 /* If the usual deallocation function is a two-argument whose second
4039 argument is of type `size_t', then we have to pass the size of
4040 the array to the deallocation function, so we will need to store
4042 fns = lookup_fnfields (TYPE_BINFO (type),
4043 ansi_opname (VEC_DELETE_EXPR),
4045 /* If there are no `operator []' members, or the lookup is
4046 ambiguous, then we don't need a cookie. */
4047 if (!fns || fns == error_mark_node)
4049 /* Loop through all of the functions. */
4050 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4055 /* Select the current function. */
4056 fn = OVL_CURRENT (fns);
4057 /* See if this function is a one-argument delete function. If
4058 it is, then it will be the usual deallocation function. */
4059 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4060 if (second_parm == void_list_node)
4062 /* Otherwise, if we have a two-argument function and the second
4063 argument is `size_t', it will be the usual deallocation
4064 function -- unless there is one-argument function, too. */
4065 if (TREE_CHAIN (second_parm) == void_list_node
4066 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4067 has_two_argument_delete_p = true;
4070 return has_two_argument_delete_p;
4073 /* Check the validity of the bases and members declared in T. Add any
4074 implicitly-generated functions (like copy-constructors and
4075 assignment operators). Compute various flag bits (like
4076 CLASSTYPE_NON_POD_T) for T. This routine works purely at the C++
4077 level: i.e., independently of the ABI in use. */
4080 check_bases_and_members (tree t)
4082 /* Nonzero if the implicitly generated copy constructor should take
4083 a non-const reference argument. */
4084 int cant_have_const_ctor;
4085 /* Nonzero if the implicitly generated assignment operator
4086 should take a non-const reference argument. */
4087 int no_const_asn_ref;
4090 /* By default, we use const reference arguments and generate default
4092 cant_have_const_ctor = 0;
4093 no_const_asn_ref = 0;
4095 /* Check all the base-classes. */
4096 check_bases (t, &cant_have_const_ctor,
4099 /* Check all the method declarations. */
4102 /* Check all the data member declarations. We cannot call
4103 check_field_decls until we have called check_bases check_methods,
4104 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4105 being set appropriately. */
4106 check_field_decls (t, &access_decls,
4107 &cant_have_const_ctor,
4110 /* A nearly-empty class has to be vptr-containing; a nearly empty
4111 class contains just a vptr. */
4112 if (!TYPE_CONTAINS_VPTR_P (t))
4113 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4115 /* Do some bookkeeping that will guide the generation of implicitly
4116 declared member functions. */
4117 TYPE_HAS_COMPLEX_INIT_REF (t)
4118 |= (TYPE_HAS_INIT_REF (t) || TYPE_CONTAINS_VPTR_P (t));
4119 TYPE_NEEDS_CONSTRUCTING (t)
4120 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_CONTAINS_VPTR_P (t));
4121 CLASSTYPE_NON_AGGREGATE (t)
4122 |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_POLYMORPHIC_P (t));
4123 CLASSTYPE_NON_POD_P (t)
4124 |= (CLASSTYPE_NON_AGGREGATE (t)
4125 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
4126 || TYPE_HAS_ASSIGN_REF (t));
4127 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
4128 |= TYPE_HAS_ASSIGN_REF (t) || TYPE_CONTAINS_VPTR_P (t);
4129 TYPE_HAS_COMPLEX_DFLT (t)
4130 |= (TYPE_HAS_DEFAULT_CONSTRUCTOR (t) || TYPE_CONTAINS_VPTR_P (t));
4132 /* Synthesize any needed methods. */
4133 add_implicitly_declared_members (t,
4134 cant_have_const_ctor,
4137 /* Create the in-charge and not-in-charge variants of constructors
4139 clone_constructors_and_destructors (t);
4141 /* Process the using-declarations. */
4142 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4143 handle_using_decl (TREE_VALUE (access_decls), t);
4145 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4146 finish_struct_methods (t);
4148 /* Figure out whether or not we will need a cookie when dynamically
4149 allocating an array of this type. */
4150 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4151 = type_requires_array_cookie (t);
4154 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4155 accordingly. If a new vfield was created (because T doesn't have a
4156 primary base class), then the newly created field is returned. It
4157 is not added to the TYPE_FIELDS list; it is the caller's
4158 responsibility to do that. Accumulate declared virtual functions
4162 create_vtable_ptr (tree t, tree* virtuals_p)
4166 /* Collect the virtual functions declared in T. */
4167 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4168 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4169 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4171 tree new_virtual = make_node (TREE_LIST);
4173 BV_FN (new_virtual) = fn;
4174 BV_DELTA (new_virtual) = integer_zero_node;
4175 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4177 TREE_CHAIN (new_virtual) = *virtuals_p;
4178 *virtuals_p = new_virtual;
4181 /* If we couldn't find an appropriate base class, create a new field
4182 here. Even if there weren't any new virtual functions, we might need a
4183 new virtual function table if we're supposed to include vptrs in
4184 all classes that need them. */
4185 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4187 /* We build this decl with vtbl_ptr_type_node, which is a
4188 `vtable_entry_type*'. It might seem more precise to use
4189 `vtable_entry_type (*)[N]' where N is the number of virtual
4190 functions. However, that would require the vtable pointer in
4191 base classes to have a different type than the vtable pointer
4192 in derived classes. We could make that happen, but that
4193 still wouldn't solve all the problems. In particular, the
4194 type-based alias analysis code would decide that assignments
4195 to the base class vtable pointer can't alias assignments to
4196 the derived class vtable pointer, since they have different
4197 types. Thus, in a derived class destructor, where the base
4198 class constructor was inlined, we could generate bad code for
4199 setting up the vtable pointer.
4201 Therefore, we use one type for all vtable pointers. We still
4202 use a type-correct type; it's just doesn't indicate the array
4203 bounds. That's better than using `void*' or some such; it's
4204 cleaner, and it let's the alias analysis code know that these
4205 stores cannot alias stores to void*! */
4208 field = build_decl (FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4209 DECL_VIRTUAL_P (field) = 1;
4210 DECL_ARTIFICIAL (field) = 1;
4211 DECL_FIELD_CONTEXT (field) = t;
4212 DECL_FCONTEXT (field) = t;
4214 TYPE_VFIELD (t) = field;
4216 /* This class is non-empty. */
4217 CLASSTYPE_EMPTY_P (t) = 0;
4225 /* Fixup the inline function given by INFO now that the class is
4229 fixup_pending_inline (tree fn)
4231 if (DECL_PENDING_INLINE_INFO (fn))
4233 tree args = DECL_ARGUMENTS (fn);
4236 DECL_CONTEXT (args) = fn;
4237 args = TREE_CHAIN (args);
4242 /* Fixup the inline methods and friends in TYPE now that TYPE is
4246 fixup_inline_methods (tree type)
4248 tree method = TYPE_METHODS (type);
4249 VEC(tree,gc) *friends;
4252 if (method && TREE_CODE (method) == TREE_VEC)
4254 if (TREE_VEC_ELT (method, 1))
4255 method = TREE_VEC_ELT (method, 1);
4256 else if (TREE_VEC_ELT (method, 0))
4257 method = TREE_VEC_ELT (method, 0);
4259 method = TREE_VEC_ELT (method, 2);
4262 /* Do inline member functions. */
4263 for (; method; method = TREE_CHAIN (method))
4264 fixup_pending_inline (method);
4267 for (friends = CLASSTYPE_INLINE_FRIENDS (type), ix = 0;
4268 VEC_iterate (tree, friends, ix, method); ix++)
4269 fixup_pending_inline (method);
4270 CLASSTYPE_INLINE_FRIENDS (type) = NULL;
4273 /* Add OFFSET to all base types of BINFO which is a base in the
4274 hierarchy dominated by T.
4276 OFFSET, which is a type offset, is number of bytes. */
4279 propagate_binfo_offsets (tree binfo, tree offset)
4285 /* Update BINFO's offset. */
4286 BINFO_OFFSET (binfo)
4287 = convert (sizetype,
4288 size_binop (PLUS_EXPR,
4289 convert (ssizetype, BINFO_OFFSET (binfo)),
4292 /* Find the primary base class. */
4293 primary_binfo = get_primary_binfo (binfo);
4295 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4296 propagate_binfo_offsets (primary_binfo, offset);
4298 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4300 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4302 /* Don't do the primary base twice. */
4303 if (base_binfo == primary_binfo)
4306 if (BINFO_VIRTUAL_P (base_binfo))
4309 propagate_binfo_offsets (base_binfo, offset);
4313 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4314 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4315 empty subobjects of T. */
4318 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4322 bool first_vbase = true;
4325 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4328 if (!abi_version_at_least(2))
4330 /* In G++ 3.2, we incorrectly rounded the size before laying out
4331 the virtual bases. */
4332 finish_record_layout (rli, /*free_p=*/false);
4333 #ifdef STRUCTURE_SIZE_BOUNDARY
4334 /* Packed structures don't need to have minimum size. */
4335 if (! TYPE_PACKED (t))
4336 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4338 rli->offset = TYPE_SIZE_UNIT (t);
4339 rli->bitpos = bitsize_zero_node;
4340 rli->record_align = TYPE_ALIGN (t);
4343 /* Find the last field. The artificial fields created for virtual
4344 bases will go after the last extant field to date. */
4345 next_field = &TYPE_FIELDS (t);
4347 next_field = &TREE_CHAIN (*next_field);
4349 /* Go through the virtual bases, allocating space for each virtual
4350 base that is not already a primary base class. These are
4351 allocated in inheritance graph order. */
4352 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4354 if (!BINFO_VIRTUAL_P (vbase))
4357 if (!BINFO_PRIMARY_P (vbase))
4359 tree basetype = TREE_TYPE (vbase);
4361 /* This virtual base is not a primary base of any class in the
4362 hierarchy, so we have to add space for it. */
4363 next_field = build_base_field (rli, vbase,
4364 offsets, next_field);
4366 /* If the first virtual base might have been placed at a
4367 lower address, had we started from CLASSTYPE_SIZE, rather
4368 than TYPE_SIZE, issue a warning. There can be both false
4369 positives and false negatives from this warning in rare
4370 cases; to deal with all the possibilities would probably
4371 require performing both layout algorithms and comparing
4372 the results which is not particularly tractable. */
4376 (size_binop (CEIL_DIV_EXPR,
4377 round_up (CLASSTYPE_SIZE (t),
4378 CLASSTYPE_ALIGN (basetype)),
4380 BINFO_OFFSET (vbase))))
4382 "offset of virtual base %qT is not ABI-compliant and "
4383 "may change in a future version of GCC",
4386 first_vbase = false;
4391 /* Returns the offset of the byte just past the end of the base class
4395 end_of_base (tree binfo)
4399 if (is_empty_class (BINFO_TYPE (binfo)))
4400 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4401 allocate some space for it. It cannot have virtual bases, so
4402 TYPE_SIZE_UNIT is fine. */
4403 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4405 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4407 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4410 /* Returns the offset of the byte just past the end of the base class
4411 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4412 only non-virtual bases are included. */
4415 end_of_class (tree t, int include_virtuals_p)
4417 tree result = size_zero_node;
4418 VEC(tree,gc) *vbases;
4424 for (binfo = TYPE_BINFO (t), i = 0;
4425 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4427 if (!include_virtuals_p
4428 && BINFO_VIRTUAL_P (base_binfo)
4429 && (!BINFO_PRIMARY_P (base_binfo)
4430 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4433 offset = end_of_base (base_binfo);
4434 if (INT_CST_LT_UNSIGNED (result, offset))
4438 /* G++ 3.2 did not check indirect virtual bases. */
4439 if (abi_version_at_least (2) && include_virtuals_p)
4440 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4441 VEC_iterate (tree, vbases, i, base_binfo); i++)
4443 offset = end_of_base (base_binfo);
4444 if (INT_CST_LT_UNSIGNED (result, offset))
4451 /* Warn about bases of T that are inaccessible because they are
4452 ambiguous. For example:
4455 struct T : public S {};
4456 struct U : public S, public T {};
4458 Here, `(S*) new U' is not allowed because there are two `S'
4462 warn_about_ambiguous_bases (tree t)
4465 VEC(tree,gc) *vbases;
4470 /* If there are no repeated bases, nothing can be ambiguous. */
4471 if (!CLASSTYPE_REPEATED_BASE_P (t))
4474 /* Check direct bases. */
4475 for (binfo = TYPE_BINFO (t), i = 0;
4476 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4478 basetype = BINFO_TYPE (base_binfo);
4480 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4481 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4485 /* Check for ambiguous virtual bases. */
4487 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4488 VEC_iterate (tree, vbases, i, binfo); i++)
4490 basetype = BINFO_TYPE (binfo);
4492 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4493 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4498 /* Compare two INTEGER_CSTs K1 and K2. */
4501 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4503 return tree_int_cst_compare ((tree) k1, (tree) k2);
4506 /* Increase the size indicated in RLI to account for empty classes
4507 that are "off the end" of the class. */
4510 include_empty_classes (record_layout_info rli)
4515 /* It might be the case that we grew the class to allocate a
4516 zero-sized base class. That won't be reflected in RLI, yet,
4517 because we are willing to overlay multiple bases at the same
4518 offset. However, now we need to make sure that RLI is big enough
4519 to reflect the entire class. */
4520 eoc = end_of_class (rli->t,
4521 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4522 rli_size = rli_size_unit_so_far (rli);
4523 if (TREE_CODE (rli_size) == INTEGER_CST
4524 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4526 if (!abi_version_at_least (2))
4527 /* In version 1 of the ABI, the size of a class that ends with
4528 a bitfield was not rounded up to a whole multiple of a
4529 byte. Because rli_size_unit_so_far returns only the number
4530 of fully allocated bytes, any extra bits were not included
4532 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4534 /* The size should have been rounded to a whole byte. */
4535 gcc_assert (tree_int_cst_equal
4536 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4538 = size_binop (PLUS_EXPR,
4540 size_binop (MULT_EXPR,
4541 convert (bitsizetype,
4542 size_binop (MINUS_EXPR,
4544 bitsize_int (BITS_PER_UNIT)));
4545 normalize_rli (rli);
4549 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4550 BINFO_OFFSETs for all of the base-classes. Position the vtable
4551 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4554 layout_class_type (tree t, tree *virtuals_p)
4556 tree non_static_data_members;
4559 record_layout_info rli;
4560 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4561 types that appear at that offset. */
4562 splay_tree empty_base_offsets;
4563 /* True if the last field layed out was a bit-field. */
4564 bool last_field_was_bitfield = false;
4565 /* The location at which the next field should be inserted. */
4567 /* T, as a base class. */
4570 /* Keep track of the first non-static data member. */
4571 non_static_data_members = TYPE_FIELDS (t);
4573 /* Start laying out the record. */
4574 rli = start_record_layout (t);
4576 /* Mark all the primary bases in the hierarchy. */
4577 determine_primary_bases (t);
4579 /* Create a pointer to our virtual function table. */
4580 vptr = create_vtable_ptr (t, virtuals_p);
4582 /* The vptr is always the first thing in the class. */
4585 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4586 TYPE_FIELDS (t) = vptr;
4587 next_field = &TREE_CHAIN (vptr);
4588 place_field (rli, vptr);
4591 next_field = &TYPE_FIELDS (t);
4593 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4594 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4596 build_base_fields (rli, empty_base_offsets, next_field);
4598 /* Layout the non-static data members. */
4599 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4604 /* We still pass things that aren't non-static data members to
4605 the back end, in case it wants to do something with them. */
4606 if (TREE_CODE (field) != FIELD_DECL)
4608 place_field (rli, field);
4609 /* If the static data member has incomplete type, keep track
4610 of it so that it can be completed later. (The handling
4611 of pending statics in finish_record_layout is
4612 insufficient; consider:
4615 struct S2 { static S1 s1; };
4617 At this point, finish_record_layout will be called, but
4618 S1 is still incomplete.) */
4619 if (TREE_CODE (field) == VAR_DECL)
4621 maybe_register_incomplete_var (field);
4622 /* The visibility of static data members is determined
4623 at their point of declaration, not their point of
4625 determine_visibility (field);
4630 type = TREE_TYPE (field);
4631 if (type == error_mark_node)
4634 padding = NULL_TREE;
4636 /* If this field is a bit-field whose width is greater than its
4637 type, then there are some special rules for allocating
4639 if (DECL_C_BIT_FIELD (field)
4640 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4642 integer_type_kind itk;
4644 bool was_unnamed_p = false;
4645 /* We must allocate the bits as if suitably aligned for the
4646 longest integer type that fits in this many bits. type
4647 of the field. Then, we are supposed to use the left over
4648 bits as additional padding. */
4649 for (itk = itk_char; itk != itk_none; ++itk)
4650 if (INT_CST_LT (DECL_SIZE (field),
4651 TYPE_SIZE (integer_types[itk])))
4654 /* ITK now indicates a type that is too large for the
4655 field. We have to back up by one to find the largest
4657 integer_type = integer_types[itk - 1];
4659 /* Figure out how much additional padding is required. GCC
4660 3.2 always created a padding field, even if it had zero
4662 if (!abi_version_at_least (2)
4663 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4665 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4666 /* In a union, the padding field must have the full width
4667 of the bit-field; all fields start at offset zero. */
4668 padding = DECL_SIZE (field);
4671 if (TREE_CODE (t) == UNION_TYPE)
4672 warning (OPT_Wabi, "size assigned to %qT may not be "
4673 "ABI-compliant and may change in a future "
4676 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4677 TYPE_SIZE (integer_type));
4680 #ifdef PCC_BITFIELD_TYPE_MATTERS
4681 /* An unnamed bitfield does not normally affect the
4682 alignment of the containing class on a target where
4683 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4684 make any exceptions for unnamed bitfields when the
4685 bitfields are longer than their types. Therefore, we
4686 temporarily give the field a name. */
4687 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4689 was_unnamed_p = true;
4690 DECL_NAME (field) = make_anon_name ();
4693 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4694 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4695 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4696 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4697 empty_base_offsets);
4699 DECL_NAME (field) = NULL_TREE;
4700 /* Now that layout has been performed, set the size of the
4701 field to the size of its declared type; the rest of the
4702 field is effectively invisible. */
4703 DECL_SIZE (field) = TYPE_SIZE (type);
4704 /* We must also reset the DECL_MODE of the field. */
4705 if (abi_version_at_least (2))
4706 DECL_MODE (field) = TYPE_MODE (type);
4708 && DECL_MODE (field) != TYPE_MODE (type))
4709 /* Versions of G++ before G++ 3.4 did not reset the
4712 "the offset of %qD may not be ABI-compliant and may "
4713 "change in a future version of GCC", field);
4716 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4717 empty_base_offsets);
4719 /* Remember the location of any empty classes in FIELD. */
4720 if (abi_version_at_least (2))
4721 record_subobject_offsets (TREE_TYPE (field),
4722 byte_position(field),
4724 /*is_data_member=*/true);
4726 /* If a bit-field does not immediately follow another bit-field,
4727 and yet it starts in the middle of a byte, we have failed to
4728 comply with the ABI. */
4730 && DECL_C_BIT_FIELD (field)
4731 /* The TREE_NO_WARNING flag gets set by Objective-C when
4732 laying out an Objective-C class. The ObjC ABI differs
4733 from the C++ ABI, and so we do not want a warning
4735 && !TREE_NO_WARNING (field)
4736 && !last_field_was_bitfield
4737 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
4738 DECL_FIELD_BIT_OFFSET (field),
4739 bitsize_unit_node)))
4740 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
4741 "change in a future version of GCC", field);
4743 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
4744 offset of the field. */
4746 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
4747 byte_position (field))
4748 && contains_empty_class_p (TREE_TYPE (field)))
4749 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
4750 "classes to be placed at different locations in a "
4751 "future version of GCC", field);
4753 /* The middle end uses the type of expressions to determine the
4754 possible range of expression values. In order to optimize
4755 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
4756 must be made aware of the width of "i", via its type.
4758 Because C++ does not have integer types of arbitrary width,
4759 we must (for the purposes of the front end) convert from the
4760 type assigned here to the declared type of the bitfield
4761 whenever a bitfield expression is used as an rvalue.
4762 Similarly, when assigning a value to a bitfield, the value
4763 must be converted to the type given the bitfield here. */
4764 if (DECL_C_BIT_FIELD (field))
4767 unsigned HOST_WIDE_INT width;
4768 ftype = TREE_TYPE (field);
4769 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
4770 if (width != TYPE_PRECISION (ftype))
4772 = c_build_bitfield_integer_type (width,
4773 TYPE_UNSIGNED (ftype));
4776 /* If we needed additional padding after this field, add it
4782 padding_field = build_decl (FIELD_DECL,
4785 DECL_BIT_FIELD (padding_field) = 1;
4786 DECL_SIZE (padding_field) = padding;
4787 DECL_CONTEXT (padding_field) = t;
4788 DECL_ARTIFICIAL (padding_field) = 1;
4789 DECL_IGNORED_P (padding_field) = 1;
4790 layout_nonempty_base_or_field (rli, padding_field,
4792 empty_base_offsets);
4795 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
4798 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
4800 /* Make sure that we are on a byte boundary so that the size of
4801 the class without virtual bases will always be a round number
4803 rli->bitpos = round_up (rli->bitpos, BITS_PER_UNIT);
4804 normalize_rli (rli);
4807 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
4809 if (!abi_version_at_least (2))
4810 include_empty_classes(rli);
4812 /* Delete all zero-width bit-fields from the list of fields. Now
4813 that the type is laid out they are no longer important. */
4814 remove_zero_width_bit_fields (t);
4816 /* Create the version of T used for virtual bases. We do not use
4817 make_aggr_type for this version; this is an artificial type. For
4818 a POD type, we just reuse T. */
4819 if (CLASSTYPE_NON_POD_P (t) || CLASSTYPE_EMPTY_P (t))
4821 base_t = make_node (TREE_CODE (t));
4823 /* Set the size and alignment for the new type. In G++ 3.2, all
4824 empty classes were considered to have size zero when used as
4826 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
4828 TYPE_SIZE (base_t) = bitsize_zero_node;
4829 TYPE_SIZE_UNIT (base_t) = size_zero_node;
4830 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
4832 "layout of classes derived from empty class %qT "
4833 "may change in a future version of GCC",
4840 /* If the ABI version is not at least two, and the last
4841 field was a bit-field, RLI may not be on a byte
4842 boundary. In particular, rli_size_unit_so_far might
4843 indicate the last complete byte, while rli_size_so_far
4844 indicates the total number of bits used. Therefore,
4845 rli_size_so_far, rather than rli_size_unit_so_far, is
4846 used to compute TYPE_SIZE_UNIT. */
4847 eoc = end_of_class (t, /*include_virtuals_p=*/0);
4848 TYPE_SIZE_UNIT (base_t)
4849 = size_binop (MAX_EXPR,
4851 size_binop (CEIL_DIV_EXPR,
4852 rli_size_so_far (rli),
4853 bitsize_int (BITS_PER_UNIT))),
4856 = size_binop (MAX_EXPR,
4857 rli_size_so_far (rli),
4858 size_binop (MULT_EXPR,
4859 convert (bitsizetype, eoc),
4860 bitsize_int (BITS_PER_UNIT)));
4862 TYPE_ALIGN (base_t) = rli->record_align;
4863 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
4865 /* Copy the fields from T. */
4866 next_field = &TYPE_FIELDS (base_t);
4867 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4868 if (TREE_CODE (field) == FIELD_DECL)
4870 *next_field = build_decl (FIELD_DECL,
4873 DECL_CONTEXT (*next_field) = base_t;
4874 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
4875 DECL_FIELD_BIT_OFFSET (*next_field)
4876 = DECL_FIELD_BIT_OFFSET (field);
4877 DECL_SIZE (*next_field) = DECL_SIZE (field);
4878 DECL_MODE (*next_field) = DECL_MODE (field);
4879 next_field = &TREE_CHAIN (*next_field);
4882 /* Record the base version of the type. */
4883 CLASSTYPE_AS_BASE (t) = base_t;
4884 TYPE_CONTEXT (base_t) = t;
4887 CLASSTYPE_AS_BASE (t) = t;
4889 /* Every empty class contains an empty class. */
4890 if (CLASSTYPE_EMPTY_P (t))
4891 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
4893 /* Set the TYPE_DECL for this type to contain the right
4894 value for DECL_OFFSET, so that we can use it as part
4895 of a COMPONENT_REF for multiple inheritance. */
4896 layout_decl (TYPE_MAIN_DECL (t), 0);
4898 /* Now fix up any virtual base class types that we left lying
4899 around. We must get these done before we try to lay out the
4900 virtual function table. As a side-effect, this will remove the
4901 base subobject fields. */
4902 layout_virtual_bases (rli, empty_base_offsets);
4904 /* Make sure that empty classes are reflected in RLI at this
4906 include_empty_classes(rli);
4908 /* Make sure not to create any structures with zero size. */
4909 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
4911 build_decl (FIELD_DECL, NULL_TREE, char_type_node));
4913 /* Let the back end lay out the type. */
4914 finish_record_layout (rli, /*free_p=*/true);
4916 /* Warn about bases that can't be talked about due to ambiguity. */
4917 warn_about_ambiguous_bases (t);
4919 /* Now that we're done with layout, give the base fields the real types. */
4920 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4921 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
4922 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
4925 splay_tree_delete (empty_base_offsets);
4927 if (CLASSTYPE_EMPTY_P (t)
4928 && tree_int_cst_lt (sizeof_biggest_empty_class,
4929 TYPE_SIZE_UNIT (t)))
4930 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
4933 /* Determine the "key method" for the class type indicated by TYPE,
4934 and set CLASSTYPE_KEY_METHOD accordingly. */
4937 determine_key_method (tree type)
4941 if (TYPE_FOR_JAVA (type)
4942 || processing_template_decl
4943 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
4944 || CLASSTYPE_INTERFACE_KNOWN (type))
4947 /* The key method is the first non-pure virtual function that is not
4948 inline at the point of class definition. On some targets the
4949 key function may not be inline; those targets should not call
4950 this function until the end of the translation unit. */
4951 for (method = TYPE_METHODS (type); method != NULL_TREE;
4952 method = TREE_CHAIN (method))
4953 if (DECL_VINDEX (method) != NULL_TREE
4954 && ! DECL_DECLARED_INLINE_P (method)
4955 && ! DECL_PURE_VIRTUAL_P (method))
4957 CLASSTYPE_KEY_METHOD (type) = method;
4964 /* Perform processing required when the definition of T (a class type)
4968 finish_struct_1 (tree t)
4971 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
4972 tree virtuals = NULL_TREE;
4975 if (COMPLETE_TYPE_P (t))
4977 gcc_assert (IS_AGGR_TYPE (t));
4978 error ("redefinition of %q#T", t);
4983 /* If this type was previously laid out as a forward reference,
4984 make sure we lay it out again. */
4985 TYPE_SIZE (t) = NULL_TREE;
4986 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
4988 fixup_inline_methods (t);
4990 /* Make assumptions about the class; we'll reset the flags if
4992 CLASSTYPE_EMPTY_P (t) = 1;
4993 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
4994 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
4996 /* Do end-of-class semantic processing: checking the validity of the
4997 bases and members and add implicitly generated methods. */
4998 check_bases_and_members (t);
5000 /* Find the key method. */
5001 if (TYPE_CONTAINS_VPTR_P (t))
5003 /* The Itanium C++ ABI permits the key method to be chosen when
5004 the class is defined -- even though the key method so
5005 selected may later turn out to be an inline function. On
5006 some systems (such as ARM Symbian OS) the key method cannot
5007 be determined until the end of the translation unit. On such
5008 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5009 will cause the class to be added to KEYED_CLASSES. Then, in
5010 finish_file we will determine the key method. */
5011 if (targetm.cxx.key_method_may_be_inline ())
5012 determine_key_method (t);
5014 /* If a polymorphic class has no key method, we may emit the vtable
5015 in every translation unit where the class definition appears. */
5016 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5017 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5020 /* Layout the class itself. */
5021 layout_class_type (t, &virtuals);
5022 if (CLASSTYPE_AS_BASE (t) != t)
5023 /* We use the base type for trivial assignments, and hence it
5025 compute_record_mode (CLASSTYPE_AS_BASE (t));
5027 virtuals = modify_all_vtables (t, nreverse (virtuals));
5029 /* If necessary, create the primary vtable for this class. */
5030 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5032 /* We must enter these virtuals into the table. */
5033 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5034 build_primary_vtable (NULL_TREE, t);
5035 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5036 /* Here we know enough to change the type of our virtual
5037 function table, but we will wait until later this function. */
5038 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5041 if (TYPE_CONTAINS_VPTR_P (t))
5046 if (BINFO_VTABLE (TYPE_BINFO (t)))
5047 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5048 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5049 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5051 /* Add entries for virtual functions introduced by this class. */
5052 BINFO_VIRTUALS (TYPE_BINFO (t))
5053 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5055 /* Set DECL_VINDEX for all functions declared in this class. */
5056 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5058 fn = TREE_CHAIN (fn),
5059 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5060 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5062 tree fndecl = BV_FN (fn);
5064 if (DECL_THUNK_P (fndecl))
5065 /* A thunk. We should never be calling this entry directly
5066 from this vtable -- we'd use the entry for the non
5067 thunk base function. */
5068 DECL_VINDEX (fndecl) = NULL_TREE;
5069 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5070 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5074 finish_struct_bits (t);
5076 /* Complete the rtl for any static member objects of the type we're
5078 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5079 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5080 && TREE_TYPE (x) != error_mark_node
5081 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5082 DECL_MODE (x) = TYPE_MODE (t);
5084 /* Done with FIELDS...now decide whether to sort these for
5085 faster lookups later.
5087 We use a small number because most searches fail (succeeding
5088 ultimately as the search bores through the inheritance
5089 hierarchy), and we want this failure to occur quickly. */
5091 n_fields = count_fields (TYPE_FIELDS (t));
5094 struct sorted_fields_type *field_vec = GGC_NEWVAR
5095 (struct sorted_fields_type,
5096 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5097 field_vec->len = n_fields;
5098 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5099 qsort (field_vec->elts, n_fields, sizeof (tree),
5101 if (! DECL_LANG_SPECIFIC (TYPE_MAIN_DECL (t)))
5102 retrofit_lang_decl (TYPE_MAIN_DECL (t));
5103 DECL_SORTED_FIELDS (TYPE_MAIN_DECL (t)) = field_vec;
5106 /* Complain if one of the field types requires lower visibility. */
5107 constrain_class_visibility (t);
5109 /* Make the rtl for any new vtables we have created, and unmark
5110 the base types we marked. */
5113 /* Build the VTT for T. */
5116 /* This warning does not make sense for Java classes, since they
5117 cannot have destructors. */
5118 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5122 dtor = CLASSTYPE_DESTRUCTORS (t);
5123 /* Warn only if the dtor is non-private or the class has
5125 if (/* An implicitly declared destructor is always public. And,
5126 if it were virtual, we would have created it by now. */
5128 || (!DECL_VINDEX (dtor)
5129 && (!TREE_PRIVATE (dtor)
5130 || CLASSTYPE_FRIEND_CLASSES (t)
5131 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))
5132 warning (0, "%q#T has virtual functions but non-virtual destructor",
5138 if (warn_overloaded_virtual)
5141 /* Class layout, assignment of virtual table slots, etc., is now
5142 complete. Give the back end a chance to tweak the visibility of
5143 the class or perform any other required target modifications. */
5144 targetm.cxx.adjust_class_at_definition (t);
5146 maybe_suppress_debug_info (t);
5148 dump_class_hierarchy (t);
5150 /* Finish debugging output for this type. */
5151 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5154 /* When T was built up, the member declarations were added in reverse
5155 order. Rearrange them to declaration order. */
5158 unreverse_member_declarations (tree t)
5164 /* The following lists are all in reverse order. Put them in
5165 declaration order now. */
5166 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5167 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5169 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5170 reverse order, so we can't just use nreverse. */
5172 for (x = TYPE_FIELDS (t);
5173 x && TREE_CODE (x) != TYPE_DECL;
5176 next = TREE_CHAIN (x);
5177 TREE_CHAIN (x) = prev;
5182 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5184 TYPE_FIELDS (t) = prev;
5189 finish_struct (tree t, tree attributes)
5191 location_t saved_loc = input_location;
5193 /* Now that we've got all the field declarations, reverse everything
5195 unreverse_member_declarations (t);
5197 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5199 /* Nadger the current location so that diagnostics point to the start of
5200 the struct, not the end. */
5201 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5203 if (processing_template_decl)
5207 finish_struct_methods (t);
5208 TYPE_SIZE (t) = bitsize_zero_node;
5209 TYPE_SIZE_UNIT (t) = size_zero_node;
5211 /* We need to emit an error message if this type was used as a parameter
5212 and it is an abstract type, even if it is a template. We construct
5213 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5214 account and we call complete_vars with this type, which will check
5215 the PARM_DECLS. Note that while the type is being defined,
5216 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5217 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5218 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5219 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5220 if (DECL_PURE_VIRTUAL_P (x))
5221 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5225 finish_struct_1 (t);
5227 input_location = saved_loc;
5229 TYPE_BEING_DEFINED (t) = 0;
5231 if (current_class_type)
5234 error ("trying to finish struct, but kicked out due to previous parse errors");
5236 if (processing_template_decl && at_function_scope_p ())
5237 add_stmt (build_min (TAG_DEFN, t));
5242 /* Return the dynamic type of INSTANCE, if known.
5243 Used to determine whether the virtual function table is needed
5246 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5247 of our knowledge of its type. *NONNULL should be initialized
5248 before this function is called. */
5251 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5253 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5255 switch (TREE_CODE (instance))
5258 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5261 return RECUR (TREE_OPERAND (instance, 0));
5264 /* This is a call to a constructor, hence it's never zero. */
5265 if (TREE_HAS_CONSTRUCTOR (instance))
5269 return TREE_TYPE (instance);
5274 /* This is a call to a constructor, hence it's never zero. */
5275 if (TREE_HAS_CONSTRUCTOR (instance))
5279 return TREE_TYPE (instance);
5281 return RECUR (TREE_OPERAND (instance, 0));
5283 case POINTER_PLUS_EXPR:
5286 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5287 return RECUR (TREE_OPERAND (instance, 0));
5288 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5289 /* Propagate nonnull. */
5290 return RECUR (TREE_OPERAND (instance, 0));
5296 return RECUR (TREE_OPERAND (instance, 0));
5299 instance = TREE_OPERAND (instance, 0);
5302 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5303 with a real object -- given &p->f, p can still be null. */
5304 tree t = get_base_address (instance);
5305 /* ??? Probably should check DECL_WEAK here. */
5306 if (t && DECL_P (t))
5309 return RECUR (instance);
5312 /* If this component is really a base class reference, then the field
5313 itself isn't definitive. */
5314 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5315 return RECUR (TREE_OPERAND (instance, 0));
5316 return RECUR (TREE_OPERAND (instance, 1));
5320 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5321 && IS_AGGR_TYPE (TREE_TYPE (TREE_TYPE (instance))))
5325 return TREE_TYPE (TREE_TYPE (instance));
5327 /* fall through... */
5331 if (IS_AGGR_TYPE (TREE_TYPE (instance)))
5335 return TREE_TYPE (instance);
5337 else if (instance == current_class_ptr)
5342 /* if we're in a ctor or dtor, we know our type. */
5343 if (DECL_LANG_SPECIFIC (current_function_decl)
5344 && (DECL_CONSTRUCTOR_P (current_function_decl)
5345 || DECL_DESTRUCTOR_P (current_function_decl)))
5349 return TREE_TYPE (TREE_TYPE (instance));
5352 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5354 /* We only need one hash table because it is always left empty. */
5357 ht = htab_create (37,
5362 /* Reference variables should be references to objects. */
5366 /* Enter the INSTANCE in a table to prevent recursion; a
5367 variable's initializer may refer to the variable
5369 if (TREE_CODE (instance) == VAR_DECL
5370 && DECL_INITIAL (instance)
5371 && !htab_find (ht, instance))
5376 slot = htab_find_slot (ht, instance, INSERT);
5378 type = RECUR (DECL_INITIAL (instance));
5379 htab_remove_elt (ht, instance);
5392 /* Return nonzero if the dynamic type of INSTANCE is known, and
5393 equivalent to the static type. We also handle the case where
5394 INSTANCE is really a pointer. Return negative if this is a
5395 ctor/dtor. There the dynamic type is known, but this might not be
5396 the most derived base of the original object, and hence virtual
5397 bases may not be layed out according to this type.
5399 Used to determine whether the virtual function table is needed
5402 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5403 of our knowledge of its type. *NONNULL should be initialized
5404 before this function is called. */
5407 resolves_to_fixed_type_p (tree instance, int* nonnull)
5409 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 pedwarn ("declaration of %q#D", decl);
6333 pedwarn ("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) == POINTER_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 = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7128 index = size_binop (PLUS_EXPR,
7129 size_int (non_fn_entries),
7130 size_int (list_length (TREE_VALUE (l))));
7131 index = size_binop (MULT_EXPR,
7132 TYPE_SIZE_UNIT (vtable_entry_type),
7134 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7138 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7139 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7140 straighten this out. */
7141 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7142 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7145 /* For an ordinary vtable, set BINFO_VTABLE. */
7146 BINFO_VTABLE (binfo) = vtbl;
7151 static GTY(()) tree abort_fndecl_addr;
7153 /* Construct the initializer for BINFO's virtual function table. BINFO
7154 is part of the hierarchy dominated by T. If we're building a
7155 construction vtable, the ORIG_BINFO is the binfo we should use to
7156 find the actual function pointers to put in the vtable - but they
7157 can be overridden on the path to most-derived in the graph that
7158 ORIG_BINFO belongs. Otherwise,
7159 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7160 BINFO that should be indicated by the RTTI information in the
7161 vtable; it will be a base class of T, rather than T itself, if we
7162 are building a construction vtable.
7164 The value returned is a TREE_LIST suitable for wrapping in a
7165 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7166 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7167 number of non-function entries in the vtable.
7169 It might seem that this function should never be called with a
7170 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7171 base is always subsumed by a derived class vtable. However, when
7172 we are building construction vtables, we do build vtables for
7173 primary bases; we need these while the primary base is being
7177 build_vtbl_initializer (tree binfo,
7181 int* non_fn_entries_p)
7188 VEC(tree,gc) *vbases;
7190 /* Initialize VID. */
7191 memset (&vid, 0, sizeof (vid));
7194 vid.rtti_binfo = rtti_binfo;
7195 vid.last_init = &vid.inits;
7196 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7197 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7198 vid.generate_vcall_entries = true;
7199 /* The first vbase or vcall offset is at index -3 in the vtable. */
7200 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7202 /* Add entries to the vtable for RTTI. */
7203 build_rtti_vtbl_entries (binfo, &vid);
7205 /* Create an array for keeping track of the functions we've
7206 processed. When we see multiple functions with the same
7207 signature, we share the vcall offsets. */
7208 vid.fns = VEC_alloc (tree, gc, 32);
7209 /* Add the vcall and vbase offset entries. */
7210 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7212 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7213 build_vbase_offset_vtbl_entries. */
7214 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7215 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7216 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7218 /* If the target requires padding between data entries, add that now. */
7219 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7223 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7228 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7229 add = tree_cons (NULL_TREE,
7230 build1 (NOP_EXPR, vtable_entry_type,
7237 if (non_fn_entries_p)
7238 *non_fn_entries_p = list_length (vid.inits);
7240 /* Go through all the ordinary virtual functions, building up
7242 vfun_inits = NULL_TREE;
7243 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7247 tree fn, fn_original;
7248 tree init = NULL_TREE;
7252 if (DECL_THUNK_P (fn))
7254 if (!DECL_NAME (fn))
7256 if (THUNK_ALIAS (fn))
7258 fn = THUNK_ALIAS (fn);
7261 fn_original = THUNK_TARGET (fn);
7264 /* If the only definition of this function signature along our
7265 primary base chain is from a lost primary, this vtable slot will
7266 never be used, so just zero it out. This is important to avoid
7267 requiring extra thunks which cannot be generated with the function.
7269 We first check this in update_vtable_entry_for_fn, so we handle
7270 restored primary bases properly; we also need to do it here so we
7271 zero out unused slots in ctor vtables, rather than filling themff
7272 with erroneous values (though harmless, apart from relocation
7274 for (b = binfo; ; b = get_primary_binfo (b))
7276 /* We found a defn before a lost primary; go ahead as normal. */
7277 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7280 /* The nearest definition is from a lost primary; clear the
7282 if (BINFO_LOST_PRIMARY_P (b))
7284 init = size_zero_node;
7291 /* Pull the offset for `this', and the function to call, out of
7293 delta = BV_DELTA (v);
7294 vcall_index = BV_VCALL_INDEX (v);
7296 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7297 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7299 /* You can't call an abstract virtual function; it's abstract.
7300 So, we replace these functions with __pure_virtual. */
7301 if (DECL_PURE_VIRTUAL_P (fn_original))
7304 if (abort_fndecl_addr == NULL)
7305 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7306 init = abort_fndecl_addr;
7310 if (!integer_zerop (delta) || vcall_index)
7312 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7313 if (!DECL_NAME (fn))
7316 /* Take the address of the function, considering it to be of an
7317 appropriate generic type. */
7318 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7322 /* And add it to the chain of initializers. */
7323 if (TARGET_VTABLE_USES_DESCRIPTORS)
7326 if (init == size_zero_node)
7327 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7328 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7330 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7332 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7333 TREE_OPERAND (init, 0),
7334 build_int_cst (NULL_TREE, i));
7335 TREE_CONSTANT (fdesc) = 1;
7336 TREE_INVARIANT (fdesc) = 1;
7338 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7342 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7345 /* The initializers for virtual functions were built up in reverse
7346 order; straighten them out now. */
7347 vfun_inits = nreverse (vfun_inits);
7349 /* The negative offset initializers are also in reverse order. */
7350 vid.inits = nreverse (vid.inits);
7352 /* Chain the two together. */
7353 return chainon (vid.inits, vfun_inits);
7356 /* Adds to vid->inits the initializers for the vbase and vcall
7357 offsets in BINFO, which is in the hierarchy dominated by T. */
7360 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7364 /* If this is a derived class, we must first create entries
7365 corresponding to the primary base class. */
7366 b = get_primary_binfo (binfo);
7368 build_vcall_and_vbase_vtbl_entries (b, vid);
7370 /* Add the vbase entries for this base. */
7371 build_vbase_offset_vtbl_entries (binfo, vid);
7372 /* Add the vcall entries for this base. */
7373 build_vcall_offset_vtbl_entries (binfo, vid);
7376 /* Returns the initializers for the vbase offset entries in the vtable
7377 for BINFO (which is part of the class hierarchy dominated by T), in
7378 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7379 where the next vbase offset will go. */
7382 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7386 tree non_primary_binfo;
7388 /* If there are no virtual baseclasses, then there is nothing to
7390 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7395 /* We might be a primary base class. Go up the inheritance hierarchy
7396 until we find the most derived class of which we are a primary base:
7397 it is the offset of that which we need to use. */
7398 non_primary_binfo = binfo;
7399 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7403 /* If we have reached a virtual base, then it must be a primary
7404 base (possibly multi-level) of vid->binfo, or we wouldn't
7405 have called build_vcall_and_vbase_vtbl_entries for it. But it
7406 might be a lost primary, so just skip down to vid->binfo. */
7407 if (BINFO_VIRTUAL_P (non_primary_binfo))
7409 non_primary_binfo = vid->binfo;
7413 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7414 if (get_primary_binfo (b) != non_primary_binfo)
7416 non_primary_binfo = b;
7419 /* Go through the virtual bases, adding the offsets. */
7420 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7422 vbase = TREE_CHAIN (vbase))
7427 if (!BINFO_VIRTUAL_P (vbase))
7430 /* Find the instance of this virtual base in the complete
7432 b = copied_binfo (vbase, binfo);
7434 /* If we've already got an offset for this virtual base, we
7435 don't need another one. */
7436 if (BINFO_VTABLE_PATH_MARKED (b))
7438 BINFO_VTABLE_PATH_MARKED (b) = 1;
7440 /* Figure out where we can find this vbase offset. */
7441 delta = size_binop (MULT_EXPR,
7444 TYPE_SIZE_UNIT (vtable_entry_type)));
7445 if (vid->primary_vtbl_p)
7446 BINFO_VPTR_FIELD (b) = delta;
7448 if (binfo != TYPE_BINFO (t))
7449 /* The vbase offset had better be the same. */
7450 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7452 /* The next vbase will come at a more negative offset. */
7453 vid->index = size_binop (MINUS_EXPR, vid->index,
7454 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7456 /* The initializer is the delta from BINFO to this virtual base.
7457 The vbase offsets go in reverse inheritance-graph order, and
7458 we are walking in inheritance graph order so these end up in
7460 delta = size_diffop (BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7463 = build_tree_list (NULL_TREE,
7464 fold_build1 (NOP_EXPR,
7467 vid->last_init = &TREE_CHAIN (*vid->last_init);
7471 /* Adds the initializers for the vcall offset entries in the vtable
7472 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7476 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7478 /* We only need these entries if this base is a virtual base. We
7479 compute the indices -- but do not add to the vtable -- when
7480 building the main vtable for a class. */
7481 if (binfo == TYPE_BINFO (vid->derived)
7482 || (BINFO_VIRTUAL_P (binfo)
7483 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7484 correspond to VID->DERIVED), we are building a primary
7485 construction virtual table. Since this is a primary
7486 virtual table, we do not need the vcall offsets for
7488 && binfo != vid->rtti_binfo))
7490 /* We need a vcall offset for each of the virtual functions in this
7491 vtable. For example:
7493 class A { virtual void f (); };
7494 class B1 : virtual public A { virtual void f (); };
7495 class B2 : virtual public A { virtual void f (); };
7496 class C: public B1, public B2 { virtual void f (); };
7498 A C object has a primary base of B1, which has a primary base of A. A
7499 C also has a secondary base of B2, which no longer has a primary base
7500 of A. So the B2-in-C construction vtable needs a secondary vtable for
7501 A, which will adjust the A* to a B2* to call f. We have no way of
7502 knowing what (or even whether) this offset will be when we define B2,
7503 so we store this "vcall offset" in the A sub-vtable and look it up in
7504 a "virtual thunk" for B2::f.
7506 We need entries for all the functions in our primary vtable and
7507 in our non-virtual bases' secondary vtables. */
7509 /* If we are just computing the vcall indices -- but do not need
7510 the actual entries -- not that. */
7511 if (!BINFO_VIRTUAL_P (binfo))
7512 vid->generate_vcall_entries = false;
7513 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7514 add_vcall_offset_vtbl_entries_r (binfo, vid);
7518 /* Build vcall offsets, starting with those for BINFO. */
7521 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7527 /* Don't walk into virtual bases -- except, of course, for the
7528 virtual base for which we are building vcall offsets. Any
7529 primary virtual base will have already had its offsets generated
7530 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7531 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7534 /* If BINFO has a primary base, process it first. */
7535 primary_binfo = get_primary_binfo (binfo);
7537 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7539 /* Add BINFO itself to the list. */
7540 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7542 /* Scan the non-primary bases of BINFO. */
7543 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7544 if (base_binfo != primary_binfo)
7545 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7548 /* Called from build_vcall_offset_vtbl_entries_r. */
7551 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7553 /* Make entries for the rest of the virtuals. */
7554 if (abi_version_at_least (2))
7558 /* The ABI requires that the methods be processed in declaration
7559 order. G++ 3.2 used the order in the vtable. */
7560 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7562 orig_fn = TREE_CHAIN (orig_fn))
7563 if (DECL_VINDEX (orig_fn))
7564 add_vcall_offset (orig_fn, binfo, vid);
7568 tree derived_virtuals;
7571 /* If BINFO is a primary base, the most derived class which has
7572 BINFO as a primary base; otherwise, just BINFO. */
7573 tree non_primary_binfo;
7575 /* We might be a primary base class. Go up the inheritance hierarchy
7576 until we find the most derived class of which we are a primary base:
7577 it is the BINFO_VIRTUALS there that we need to consider. */
7578 non_primary_binfo = binfo;
7579 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7583 /* If we have reached a virtual base, then it must be vid->vbase,
7584 because we ignore other virtual bases in
7585 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7586 base (possibly multi-level) of vid->binfo, or we wouldn't
7587 have called build_vcall_and_vbase_vtbl_entries for it. But it
7588 might be a lost primary, so just skip down to vid->binfo. */
7589 if (BINFO_VIRTUAL_P (non_primary_binfo))
7591 gcc_assert (non_primary_binfo == vid->vbase);
7592 non_primary_binfo = vid->binfo;
7596 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7597 if (get_primary_binfo (b) != non_primary_binfo)
7599 non_primary_binfo = b;
7602 if (vid->ctor_vtbl_p)
7603 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7604 where rtti_binfo is the most derived type. */
7606 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7608 for (base_virtuals = BINFO_VIRTUALS (binfo),
7609 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7610 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7612 base_virtuals = TREE_CHAIN (base_virtuals),
7613 derived_virtuals = TREE_CHAIN (derived_virtuals),
7614 orig_virtuals = TREE_CHAIN (orig_virtuals))
7618 /* Find the declaration that originally caused this function to
7619 be present in BINFO_TYPE (binfo). */
7620 orig_fn = BV_FN (orig_virtuals);
7622 /* When processing BINFO, we only want to generate vcall slots for
7623 function slots introduced in BINFO. So don't try to generate
7624 one if the function isn't even defined in BINFO. */
7625 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7628 add_vcall_offset (orig_fn, binfo, vid);
7633 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7636 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7642 /* If there is already an entry for a function with the same
7643 signature as FN, then we do not need a second vcall offset.
7644 Check the list of functions already present in the derived
7646 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7648 if (same_signature_p (derived_entry, orig_fn)
7649 /* We only use one vcall offset for virtual destructors,
7650 even though there are two virtual table entries. */
7651 || (DECL_DESTRUCTOR_P (derived_entry)
7652 && DECL_DESTRUCTOR_P (orig_fn)))
7656 /* If we are building these vcall offsets as part of building
7657 the vtable for the most derived class, remember the vcall
7659 if (vid->binfo == TYPE_BINFO (vid->derived))
7661 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
7662 CLASSTYPE_VCALL_INDICES (vid->derived),
7664 elt->purpose = orig_fn;
7665 elt->value = vid->index;
7668 /* The next vcall offset will be found at a more negative
7670 vid->index = size_binop (MINUS_EXPR, vid->index,
7671 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7673 /* Keep track of this function. */
7674 VEC_safe_push (tree, gc, vid->fns, orig_fn);
7676 if (vid->generate_vcall_entries)
7681 /* Find the overriding function. */
7682 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
7683 if (fn == error_mark_node)
7684 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
7688 base = TREE_VALUE (fn);
7690 /* The vbase we're working on is a primary base of
7691 vid->binfo. But it might be a lost primary, so its
7692 BINFO_OFFSET might be wrong, so we just use the
7693 BINFO_OFFSET from vid->binfo. */
7694 vcall_offset = size_diffop (BINFO_OFFSET (base),
7695 BINFO_OFFSET (vid->binfo));
7696 vcall_offset = fold_build1 (NOP_EXPR, vtable_entry_type,
7699 /* Add the initializer to the vtable. */
7700 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
7701 vid->last_init = &TREE_CHAIN (*vid->last_init);
7705 /* Return vtbl initializers for the RTTI entries corresponding to the
7706 BINFO's vtable. The RTTI entries should indicate the object given
7707 by VID->rtti_binfo. */
7710 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
7719 basetype = BINFO_TYPE (binfo);
7720 t = BINFO_TYPE (vid->rtti_binfo);
7722 /* To find the complete object, we will first convert to our most
7723 primary base, and then add the offset in the vtbl to that value. */
7725 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
7726 && !BINFO_LOST_PRIMARY_P (b))
7730 primary_base = get_primary_binfo (b);
7731 gcc_assert (BINFO_PRIMARY_P (primary_base)
7732 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
7735 offset = size_diffop (BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
7737 /* The second entry is the address of the typeinfo object. */
7739 decl = build_address (get_tinfo_decl (t));
7741 decl = integer_zero_node;
7743 /* Convert the declaration to a type that can be stored in the
7745 init = build_nop (vfunc_ptr_type_node, decl);
7746 *vid->last_init = build_tree_list (NULL_TREE, init);
7747 vid->last_init = &TREE_CHAIN (*vid->last_init);
7749 /* Add the offset-to-top entry. It comes earlier in the vtable than
7750 the typeinfo entry. Convert the offset to look like a
7751 function pointer, so that we can put it in the vtable. */
7752 init = build_nop (vfunc_ptr_type_node, offset);
7753 *vid->last_init = build_tree_list (NULL_TREE, init);
7754 vid->last_init = &TREE_CHAIN (*vid->last_init);
7757 /* Fold a OBJ_TYPE_REF expression to the address of a function.
7758 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
7761 cp_fold_obj_type_ref (tree ref, tree known_type)
7763 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
7764 HOST_WIDE_INT i = 0;
7765 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
7770 i += (TARGET_VTABLE_USES_DESCRIPTORS
7771 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
7777 #ifdef ENABLE_CHECKING
7778 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
7779 DECL_VINDEX (fndecl)));
7782 cgraph_node (fndecl)->local.vtable_method = true;
7784 return build_address (fndecl);
7787 #include "gt-cp-class.h"