1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009
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 bool check_bitfield_decl (tree);
143 static void check_field_decl (tree, tree, int *, int *, int *);
144 static void check_field_decls (tree, tree *, int *, int *);
145 static tree *build_base_field (record_layout_info, tree, splay_tree, tree *);
146 static void build_base_fields (record_layout_info, splay_tree, tree *);
147 static void check_methods (tree);
148 static void remove_zero_width_bit_fields (tree);
149 static void check_bases (tree, int *, int *);
150 static void check_bases_and_members (tree);
151 static tree create_vtable_ptr (tree, tree *);
152 static void include_empty_classes (record_layout_info);
153 static void layout_class_type (tree, tree *);
154 static void 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 (record_layout_info, 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 = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
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 /* Don't bother with the calculations inside sizeof; they'll ICE if the
297 source type is incomplete and the pointer value doesn't matter. */
300 expr = build_nop (build_pointer_type (target_type), expr);
302 expr = build_indirect_ref (EXPR_LOCATION (expr), expr, NULL);
306 /* Do we need to check for a null pointer? */
307 if (want_pointer && !nonnull)
309 /* If we know the conversion will not actually change the value
310 of EXPR, then we can avoid testing the expression for NULL.
311 We have to avoid generating a COMPONENT_REF for a base class
312 field, because other parts of the compiler know that such
313 expressions are always non-NULL. */
314 if (!virtual_access && integer_zerop (offset))
317 /* TARGET_TYPE has been extracted from BINFO, and, is
318 therefore always cv-unqualified. Extract the
319 cv-qualifiers from EXPR so that the expression returned
320 matches the input. */
321 class_type = TREE_TYPE (TREE_TYPE (expr));
323 = cp_build_qualified_type (target_type,
324 cp_type_quals (class_type));
325 return build_nop (build_pointer_type (target_type), expr);
327 null_test = error_mark_node;
330 /* Protect against multiple evaluation if necessary. */
331 if (TREE_SIDE_EFFECTS (expr) && (null_test || virtual_access))
332 expr = save_expr (expr);
334 /* Now that we've saved expr, build the real null test. */
337 tree zero = cp_convert (TREE_TYPE (expr), integer_zero_node);
338 null_test = fold_build2 (NE_EXPR, boolean_type_node,
342 /* If this is a simple base reference, express it as a COMPONENT_REF. */
343 if (code == PLUS_EXPR && !virtual_access
344 /* We don't build base fields for empty bases, and they aren't very
345 interesting to the optimizers anyway. */
348 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
349 expr = build_simple_base_path (expr, binfo);
351 expr = build_address (expr);
352 target_type = TREE_TYPE (expr);
358 /* Going via virtual base V_BINFO. We need the static offset
359 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
360 V_BINFO. That offset is an entry in D_BINFO's vtable. */
363 if (fixed_type_p < 0 && in_base_initializer)
365 /* In a base member initializer, we cannot rely on the
366 vtable being set up. We have to indirect via the
370 t = TREE_TYPE (TYPE_VFIELD (current_class_type));
371 t = build_pointer_type (t);
372 v_offset = convert (t, current_vtt_parm);
373 v_offset = cp_build_indirect_ref (v_offset, NULL,
374 tf_warning_or_error);
377 v_offset = build_vfield_ref (cp_build_indirect_ref (expr, NULL,
378 tf_warning_or_error),
379 TREE_TYPE (TREE_TYPE (expr)));
381 v_offset = build2 (POINTER_PLUS_EXPR, TREE_TYPE (v_offset),
382 v_offset, fold_convert (sizetype, BINFO_VPTR_FIELD (v_binfo)));
383 v_offset = build1 (NOP_EXPR,
384 build_pointer_type (ptrdiff_type_node),
386 v_offset = cp_build_indirect_ref (v_offset, NULL, tf_warning_or_error);
387 TREE_CONSTANT (v_offset) = 1;
389 offset = convert_to_integer (ptrdiff_type_node,
391 BINFO_OFFSET (v_binfo)));
393 if (!integer_zerop (offset))
394 v_offset = build2 (code, ptrdiff_type_node, v_offset, offset);
396 if (fixed_type_p < 0)
397 /* Negative fixed_type_p means this is a constructor or destructor;
398 virtual base layout is fixed in in-charge [cd]tors, but not in
400 offset = build3 (COND_EXPR, ptrdiff_type_node,
401 build2 (EQ_EXPR, boolean_type_node,
402 current_in_charge_parm, integer_zero_node),
404 convert_to_integer (ptrdiff_type_node,
405 BINFO_OFFSET (binfo)));
410 target_type = cp_build_qualified_type
411 (target_type, cp_type_quals (TREE_TYPE (TREE_TYPE (expr))));
412 ptr_target_type = build_pointer_type (target_type);
414 target_type = ptr_target_type;
416 expr = build1 (NOP_EXPR, ptr_target_type, expr);
418 if (!integer_zerop (offset))
420 offset = fold_convert (sizetype, offset);
421 if (code == MINUS_EXPR)
422 offset = fold_build1 (NEGATE_EXPR, sizetype, offset);
423 expr = build2 (POINTER_PLUS_EXPR, ptr_target_type, expr, offset);
429 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
433 expr = fold_build3 (COND_EXPR, target_type, null_test, expr,
434 fold_build1 (NOP_EXPR, target_type,
440 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
441 Perform a derived-to-base conversion by recursively building up a
442 sequence of COMPONENT_REFs to the appropriate base fields. */
445 build_simple_base_path (tree expr, tree binfo)
447 tree type = BINFO_TYPE (binfo);
448 tree d_binfo = BINFO_INHERITANCE_CHAIN (binfo);
451 if (d_binfo == NULL_TREE)
455 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) == type);
457 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
458 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
459 an lvalue in the front end; only _DECLs and _REFs are lvalues
461 temp = unary_complex_lvalue (ADDR_EXPR, expr);
463 expr = cp_build_indirect_ref (temp, NULL, tf_warning_or_error);
469 expr = build_simple_base_path (expr, d_binfo);
471 for (field = TYPE_FIELDS (BINFO_TYPE (d_binfo));
472 field; field = TREE_CHAIN (field))
473 /* Is this the base field created by build_base_field? */
474 if (TREE_CODE (field) == FIELD_DECL
475 && DECL_FIELD_IS_BASE (field)
476 && TREE_TYPE (field) == type)
478 /* We don't use build_class_member_access_expr here, as that
479 has unnecessary checks, and more importantly results in
480 recursive calls to dfs_walk_once. */
481 int type_quals = cp_type_quals (TREE_TYPE (expr));
483 expr = build3 (COMPONENT_REF,
484 cp_build_qualified_type (type, type_quals),
485 expr, field, NULL_TREE);
486 expr = fold_if_not_in_template (expr);
488 /* Mark the expression const or volatile, as appropriate.
489 Even though we've dealt with the type above, we still have
490 to mark the expression itself. */
491 if (type_quals & TYPE_QUAL_CONST)
492 TREE_READONLY (expr) = 1;
493 if (type_quals & TYPE_QUAL_VOLATILE)
494 TREE_THIS_VOLATILE (expr) = 1;
499 /* Didn't find the base field?!? */
503 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
504 type is a class type or a pointer to a class type. In the former
505 case, TYPE is also a class type; in the latter it is another
506 pointer type. If CHECK_ACCESS is true, an error message is emitted
507 if TYPE is inaccessible. If OBJECT has pointer type, the value is
508 assumed to be non-NULL. */
511 convert_to_base (tree object, tree type, bool check_access, bool nonnull)
516 if (TYPE_PTR_P (TREE_TYPE (object)))
518 object_type = TREE_TYPE (TREE_TYPE (object));
519 type = TREE_TYPE (type);
522 object_type = TREE_TYPE (object);
524 binfo = lookup_base (object_type, type,
525 check_access ? ba_check : ba_unique,
527 if (!binfo || binfo == error_mark_node)
528 return error_mark_node;
530 return build_base_path (PLUS_EXPR, object, binfo, nonnull);
533 /* EXPR is an expression with unqualified class type. BASE is a base
534 binfo of that class type. Returns EXPR, converted to the BASE
535 type. This function assumes that EXPR is the most derived class;
536 therefore virtual bases can be found at their static offsets. */
539 convert_to_base_statically (tree expr, tree base)
543 expr_type = TREE_TYPE (expr);
544 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (base), expr_type))
548 pointer_type = build_pointer_type (expr_type);
550 /* We use fold_build2 and fold_convert below to simplify the trees
551 provided to the optimizers. It is not safe to call these functions
552 when processing a template because they do not handle C++-specific
554 gcc_assert (!processing_template_decl);
555 expr = cp_build_unary_op (ADDR_EXPR, expr, /*noconvert=*/1,
556 tf_warning_or_error);
557 if (!integer_zerop (BINFO_OFFSET (base)))
558 expr = fold_build2 (POINTER_PLUS_EXPR, pointer_type, expr,
559 fold_convert (sizetype, BINFO_OFFSET (base)));
560 expr = fold_convert (build_pointer_type (BINFO_TYPE (base)), expr);
561 expr = build_fold_indirect_ref (expr);
569 build_vfield_ref (tree datum, tree type)
571 tree vfield, vcontext;
573 if (datum == error_mark_node)
574 return error_mark_node;
576 /* First, convert to the requested type. */
577 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
578 datum = convert_to_base (datum, type, /*check_access=*/false,
581 /* Second, the requested type may not be the owner of its own vptr.
582 If not, convert to the base class that owns it. We cannot use
583 convert_to_base here, because VCONTEXT may appear more than once
584 in the inheritance hierarchy of TYPE, and thus direct conversion
585 between the types may be ambiguous. Following the path back up
586 one step at a time via primary bases avoids the problem. */
587 vfield = TYPE_VFIELD (type);
588 vcontext = DECL_CONTEXT (vfield);
589 while (!same_type_ignoring_top_level_qualifiers_p (vcontext, type))
591 datum = build_simple_base_path (datum, CLASSTYPE_PRIMARY_BINFO (type));
592 type = TREE_TYPE (datum);
595 return build3 (COMPONENT_REF, TREE_TYPE (vfield), datum, vfield, NULL_TREE);
598 /* Given an object INSTANCE, return an expression which yields the
599 vtable element corresponding to INDEX. There are many special
600 cases for INSTANCE which we take care of here, mainly to avoid
601 creating extra tree nodes when we don't have to. */
604 build_vtbl_ref_1 (tree instance, tree idx)
607 tree vtbl = NULL_TREE;
609 /* Try to figure out what a reference refers to, and
610 access its virtual function table directly. */
613 tree fixed_type = fixed_type_or_null (instance, NULL, &cdtorp);
615 tree basetype = non_reference (TREE_TYPE (instance));
617 if (fixed_type && !cdtorp)
619 tree binfo = lookup_base (fixed_type, basetype,
620 ba_unique | ba_quiet, NULL);
622 vtbl = unshare_expr (BINFO_VTABLE (binfo));
626 vtbl = build_vfield_ref (instance, basetype);
628 assemble_external (vtbl);
630 aref = build_array_ref (vtbl, idx, input_location);
631 TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
637 build_vtbl_ref (tree instance, tree idx)
639 tree aref = build_vtbl_ref_1 (instance, idx);
644 /* Given a stable object pointer INSTANCE_PTR, return an expression which
645 yields a function pointer corresponding to vtable element INDEX. */
648 build_vfn_ref (tree instance_ptr, tree idx)
652 aref = build_vtbl_ref_1 (cp_build_indirect_ref (instance_ptr, 0,
653 tf_warning_or_error),
656 /* When using function descriptors, the address of the
657 vtable entry is treated as a function pointer. */
658 if (TARGET_VTABLE_USES_DESCRIPTORS)
659 aref = build1 (NOP_EXPR, TREE_TYPE (aref),
660 cp_build_unary_op (ADDR_EXPR, aref, /*noconvert=*/1,
661 tf_warning_or_error));
663 /* Remember this as a method reference, for later devirtualization. */
664 aref = build3 (OBJ_TYPE_REF, TREE_TYPE (aref), aref, instance_ptr, idx);
669 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
670 for the given TYPE. */
673 get_vtable_name (tree type)
675 return mangle_vtbl_for_type (type);
678 /* DECL is an entity associated with TYPE, like a virtual table or an
679 implicitly generated constructor. Determine whether or not DECL
680 should have external or internal linkage at the object file
681 level. This routine does not deal with COMDAT linkage and other
682 similar complexities; it simply sets TREE_PUBLIC if it possible for
683 entities in other translation units to contain copies of DECL, in
687 set_linkage_according_to_type (tree type, tree decl)
689 /* If TYPE involves a local class in a function with internal
690 linkage, then DECL should have internal linkage too. Other local
691 classes have no linkage -- but if their containing functions
692 have external linkage, it makes sense for DECL to have external
693 linkage too. That will allow template definitions to be merged,
695 if (no_linkage_check (type, /*relaxed_p=*/true))
697 TREE_PUBLIC (decl) = 0;
698 DECL_INTERFACE_KNOWN (decl) = 1;
701 TREE_PUBLIC (decl) = 1;
704 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
705 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
706 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
709 build_vtable (tree class_type, tree name, tree vtable_type)
713 decl = build_lang_decl (VAR_DECL, name, vtable_type);
714 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
715 now to avoid confusion in mangle_decl. */
716 SET_DECL_ASSEMBLER_NAME (decl, name);
717 DECL_CONTEXT (decl) = class_type;
718 DECL_ARTIFICIAL (decl) = 1;
719 TREE_STATIC (decl) = 1;
720 TREE_READONLY (decl) = 1;
721 DECL_VIRTUAL_P (decl) = 1;
722 DECL_ALIGN (decl) = TARGET_VTABLE_ENTRY_ALIGN;
723 DECL_VTABLE_OR_VTT_P (decl) = 1;
724 /* At one time the vtable info was grabbed 2 words at a time. This
725 fails on sparc unless you have 8-byte alignment. (tiemann) */
726 DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node),
728 set_linkage_according_to_type (class_type, decl);
729 /* The vtable has not been defined -- yet. */
730 DECL_EXTERNAL (decl) = 1;
731 DECL_NOT_REALLY_EXTERN (decl) = 1;
733 /* Mark the VAR_DECL node representing the vtable itself as a
734 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
735 is rather important that such things be ignored because any
736 effort to actually generate DWARF for them will run into
737 trouble when/if we encounter code like:
740 struct S { virtual void member (); };
742 because the artificial declaration of the vtable itself (as
743 manufactured by the g++ front end) will say that the vtable is
744 a static member of `S' but only *after* the debug output for
745 the definition of `S' has already been output. This causes
746 grief because the DWARF entry for the definition of the vtable
747 will try to refer back to an earlier *declaration* of the
748 vtable as a static member of `S' and there won't be one. We
749 might be able to arrange to have the "vtable static member"
750 attached to the member list for `S' before the debug info for
751 `S' get written (which would solve the problem) but that would
752 require more intrusive changes to the g++ front end. */
753 DECL_IGNORED_P (decl) = 1;
758 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
759 or even complete. If this does not exist, create it. If COMPLETE is
760 nonzero, then complete the definition of it -- that will render it
761 impossible to actually build the vtable, but is useful to get at those
762 which are known to exist in the runtime. */
765 get_vtable_decl (tree type, int complete)
769 if (CLASSTYPE_VTABLES (type))
770 return CLASSTYPE_VTABLES (type);
772 decl = build_vtable (type, get_vtable_name (type), vtbl_type_node);
773 CLASSTYPE_VTABLES (type) = decl;
777 DECL_EXTERNAL (decl) = 1;
778 finish_decl (decl, NULL_TREE, NULL_TREE);
784 /* Build the primary virtual function table for TYPE. If BINFO is
785 non-NULL, build the vtable starting with the initial approximation
786 that it is the same as the one which is the head of the association
787 list. Returns a nonzero value if a new vtable is actually
791 build_primary_vtable (tree binfo, tree type)
796 decl = get_vtable_decl (type, /*complete=*/0);
800 if (BINFO_NEW_VTABLE_MARKED (binfo))
801 /* We have already created a vtable for this base, so there's
802 no need to do it again. */
805 virtuals = copy_list (BINFO_VIRTUALS (binfo));
806 TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo));
807 DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl));
808 DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl));
812 gcc_assert (TREE_TYPE (decl) == vtbl_type_node);
813 virtuals = NULL_TREE;
816 #ifdef GATHER_STATISTICS
818 n_vtable_elems += list_length (virtuals);
821 /* Initialize the association list for this type, based
822 on our first approximation. */
823 BINFO_VTABLE (TYPE_BINFO (type)) = decl;
824 BINFO_VIRTUALS (TYPE_BINFO (type)) = virtuals;
825 SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type));
829 /* Give BINFO a new virtual function table which is initialized
830 with a skeleton-copy of its original initialization. The only
831 entry that changes is the `delta' entry, so we can really
832 share a lot of structure.
834 FOR_TYPE is the most derived type which caused this table to
837 Returns nonzero if we haven't met BINFO before.
839 The order in which vtables are built (by calling this function) for
840 an object must remain the same, otherwise a binary incompatibility
844 build_secondary_vtable (tree binfo)
846 if (BINFO_NEW_VTABLE_MARKED (binfo))
847 /* We already created a vtable for this base. There's no need to
851 /* Remember that we've created a vtable for this BINFO, so that we
852 don't try to do so again. */
853 SET_BINFO_NEW_VTABLE_MARKED (binfo);
855 /* Make fresh virtual list, so we can smash it later. */
856 BINFO_VIRTUALS (binfo) = copy_list (BINFO_VIRTUALS (binfo));
858 /* Secondary vtables are laid out as part of the same structure as
859 the primary vtable. */
860 BINFO_VTABLE (binfo) = NULL_TREE;
864 /* Create a new vtable for BINFO which is the hierarchy dominated by
865 T. Return nonzero if we actually created a new vtable. */
868 make_new_vtable (tree t, tree binfo)
870 if (binfo == TYPE_BINFO (t))
871 /* In this case, it is *type*'s vtable we are modifying. We start
872 with the approximation that its vtable is that of the
873 immediate base class. */
874 return build_primary_vtable (binfo, t);
876 /* This is our very own copy of `basetype' to play with. Later,
877 we will fill in all the virtual functions that override the
878 virtual functions in these base classes which are not defined
879 by the current type. */
880 return build_secondary_vtable (binfo);
883 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
884 (which is in the hierarchy dominated by T) list FNDECL as its
885 BV_FN. DELTA is the required constant adjustment from the `this'
886 pointer where the vtable entry appears to the `this' required when
887 the function is actually called. */
890 modify_vtable_entry (tree t,
900 if (fndecl != BV_FN (v)
901 || !tree_int_cst_equal (delta, BV_DELTA (v)))
903 /* We need a new vtable for BINFO. */
904 if (make_new_vtable (t, binfo))
906 /* If we really did make a new vtable, we also made a copy
907 of the BINFO_VIRTUALS list. Now, we have to find the
908 corresponding entry in that list. */
909 *virtuals = BINFO_VIRTUALS (binfo);
910 while (BV_FN (*virtuals) != BV_FN (v))
911 *virtuals = TREE_CHAIN (*virtuals);
915 BV_DELTA (v) = delta;
916 BV_VCALL_INDEX (v) = NULL_TREE;
922 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
923 the USING_DECL naming METHOD. Returns true if the method could be
924 added to the method vec. */
927 add_method (tree type, tree method, tree using_decl)
931 bool template_conv_p = false;
933 VEC(tree,gc) *method_vec;
935 bool insert_p = false;
939 if (method == error_mark_node)
942 complete_p = COMPLETE_TYPE_P (type);
943 conv_p = DECL_CONV_FN_P (method);
945 template_conv_p = (TREE_CODE (method) == TEMPLATE_DECL
946 && DECL_TEMPLATE_CONV_FN_P (method));
948 method_vec = CLASSTYPE_METHOD_VEC (type);
951 /* Make a new method vector. We start with 8 entries. We must
952 allocate at least two (for constructors and destructors), and
953 we're going to end up with an assignment operator at some
955 method_vec = VEC_alloc (tree, gc, 8);
956 /* Create slots for constructors and destructors. */
957 VEC_quick_push (tree, method_vec, NULL_TREE);
958 VEC_quick_push (tree, method_vec, NULL_TREE);
959 CLASSTYPE_METHOD_VEC (type) = method_vec;
962 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
963 grok_special_member_properties (method);
965 /* Constructors and destructors go in special slots. */
966 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method))
967 slot = CLASSTYPE_CONSTRUCTOR_SLOT;
968 else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
970 slot = CLASSTYPE_DESTRUCTOR_SLOT;
972 if (TYPE_FOR_JAVA (type))
974 if (!DECL_ARTIFICIAL (method))
975 error ("Java class %qT cannot have a destructor", type);
976 else if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
977 error ("Java class %qT cannot have an implicit non-trivial "
987 /* See if we already have an entry with this name. */
988 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
989 VEC_iterate (tree, method_vec, slot, m);
995 if (TREE_CODE (m) == TEMPLATE_DECL
996 && DECL_TEMPLATE_CONV_FN_P (m))
1000 if (conv_p && !DECL_CONV_FN_P (m))
1002 if (DECL_NAME (m) == DECL_NAME (method))
1008 && !DECL_CONV_FN_P (m)
1009 && DECL_NAME (m) > DECL_NAME (method))
1013 current_fns = insert_p ? NULL_TREE : VEC_index (tree, method_vec, slot);
1015 /* Check to see if we've already got this method. */
1016 for (fns = current_fns; fns; fns = OVL_NEXT (fns))
1018 tree fn = OVL_CURRENT (fns);
1024 if (TREE_CODE (fn) != TREE_CODE (method))
1027 /* [over.load] Member function declarations with the
1028 same name and the same parameter types cannot be
1029 overloaded if any of them is a static member
1030 function declaration.
1032 [namespace.udecl] When a using-declaration brings names
1033 from a base class into a derived class scope, member
1034 functions in the derived class override and/or hide member
1035 functions with the same name and parameter types in a base
1036 class (rather than conflicting). */
1037 fn_type = TREE_TYPE (fn);
1038 method_type = TREE_TYPE (method);
1039 parms1 = TYPE_ARG_TYPES (fn_type);
1040 parms2 = TYPE_ARG_TYPES (method_type);
1042 /* Compare the quals on the 'this' parm. Don't compare
1043 the whole types, as used functions are treated as
1044 coming from the using class in overload resolution. */
1045 if (! DECL_STATIC_FUNCTION_P (fn)
1046 && ! DECL_STATIC_FUNCTION_P (method)
1047 && TREE_TYPE (TREE_VALUE (parms1)) != error_mark_node
1048 && TREE_TYPE (TREE_VALUE (parms2)) != error_mark_node
1049 && (TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms1)))
1050 != TYPE_QUALS (TREE_TYPE (TREE_VALUE (parms2)))))
1053 /* For templates, the return type and template parameters
1054 must be identical. */
1055 if (TREE_CODE (fn) == TEMPLATE_DECL
1056 && (!same_type_p (TREE_TYPE (fn_type),
1057 TREE_TYPE (method_type))
1058 || !comp_template_parms (DECL_TEMPLATE_PARMS (fn),
1059 DECL_TEMPLATE_PARMS (method))))
1062 if (! DECL_STATIC_FUNCTION_P (fn))
1063 parms1 = TREE_CHAIN (parms1);
1064 if (! DECL_STATIC_FUNCTION_P (method))
1065 parms2 = TREE_CHAIN (parms2);
1067 if (compparms (parms1, parms2)
1068 && (!DECL_CONV_FN_P (fn)
1069 || same_type_p (TREE_TYPE (fn_type),
1070 TREE_TYPE (method_type))))
1074 if (DECL_CONTEXT (fn) == type)
1075 /* Defer to the local function. */
1077 if (DECL_CONTEXT (fn) == DECL_CONTEXT (method))
1078 error ("repeated using declaration %q+D", using_decl);
1080 error ("using declaration %q+D conflicts with a previous using declaration",
1085 error ("%q+#D cannot be overloaded", method);
1086 error ("with %q+#D", fn);
1089 /* We don't call duplicate_decls here to merge the
1090 declarations because that will confuse things if the
1091 methods have inline definitions. In particular, we
1092 will crash while processing the definitions. */
1097 /* A class should never have more than one destructor. */
1098 if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
1101 /* Add the new binding. */
1102 overload = build_overload (method, current_fns);
1105 TYPE_HAS_CONVERSION (type) = 1;
1106 else if (slot >= CLASSTYPE_FIRST_CONVERSION_SLOT && !complete_p)
1107 push_class_level_binding (DECL_NAME (method), overload);
1113 /* We only expect to add few methods in the COMPLETE_P case, so
1114 just make room for one more method in that case. */
1116 reallocated = VEC_reserve_exact (tree, gc, method_vec, 1);
1118 reallocated = VEC_reserve (tree, gc, method_vec, 1);
1120 CLASSTYPE_METHOD_VEC (type) = method_vec;
1121 if (slot == VEC_length (tree, method_vec))
1122 VEC_quick_push (tree, method_vec, overload);
1124 VEC_quick_insert (tree, method_vec, slot, overload);
1127 /* Replace the current slot. */
1128 VEC_replace (tree, method_vec, slot, overload);
1132 /* Subroutines of finish_struct. */
1134 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1135 legit, otherwise return 0. */
1138 alter_access (tree t, tree fdecl, tree access)
1142 if (!DECL_LANG_SPECIFIC (fdecl))
1143 retrofit_lang_decl (fdecl);
1145 gcc_assert (!DECL_DISCRIMINATOR_P (fdecl));
1147 elem = purpose_member (t, DECL_ACCESS (fdecl));
1150 if (TREE_VALUE (elem) != access)
1152 if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL)
1153 error ("conflicting access specifications for method"
1154 " %q+D, ignored", TREE_TYPE (fdecl));
1156 error ("conflicting access specifications for field %qE, ignored",
1161 /* They're changing the access to the same thing they changed
1162 it to before. That's OK. */
1168 perform_or_defer_access_check (TYPE_BINFO (t), fdecl, fdecl);
1169 DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl));
1175 /* Process the USING_DECL, which is a member of T. */
1178 handle_using_decl (tree using_decl, tree t)
1180 tree decl = USING_DECL_DECLS (using_decl);
1181 tree name = DECL_NAME (using_decl);
1183 = TREE_PRIVATE (using_decl) ? access_private_node
1184 : TREE_PROTECTED (using_decl) ? access_protected_node
1185 : access_public_node;
1186 tree flist = NULL_TREE;
1189 gcc_assert (!processing_template_decl && decl);
1191 old_value = lookup_member (t, name, /*protect=*/0, /*want_type=*/false);
1194 if (is_overloaded_fn (old_value))
1195 old_value = OVL_CURRENT (old_value);
1197 if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t)
1200 old_value = NULL_TREE;
1203 cp_emit_debug_info_for_using (decl, USING_DECL_SCOPE (using_decl));
1205 if (is_overloaded_fn (decl))
1210 else if (is_overloaded_fn (old_value))
1213 /* It's OK to use functions from a base when there are functions with
1214 the same name already present in the current class. */;
1217 error ("%q+D invalid in %q#T", using_decl, t);
1218 error (" because of local method %q+#D with same name",
1219 OVL_CURRENT (old_value));
1223 else if (!DECL_ARTIFICIAL (old_value))
1225 error ("%q+D invalid in %q#T", using_decl, t);
1226 error (" because of local member %q+#D with same name", old_value);
1230 /* Make type T see field decl FDECL with access ACCESS. */
1232 for (; flist; flist = OVL_NEXT (flist))
1234 add_method (t, OVL_CURRENT (flist), using_decl);
1235 alter_access (t, OVL_CURRENT (flist), access);
1238 alter_access (t, decl, access);
1241 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1242 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1243 properties of the bases. */
1246 check_bases (tree t,
1247 int* cant_have_const_ctor_p,
1248 int* no_const_asn_ref_p)
1251 int seen_non_virtual_nearly_empty_base_p;
1255 seen_non_virtual_nearly_empty_base_p = 0;
1257 for (binfo = TYPE_BINFO (t), i = 0;
1258 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
1260 tree basetype = TREE_TYPE (base_binfo);
1262 gcc_assert (COMPLETE_TYPE_P (basetype));
1264 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1265 here because the case of virtual functions but non-virtual
1266 dtor is handled in finish_struct_1. */
1267 if (!TYPE_POLYMORPHIC_P (basetype))
1268 warning (OPT_Weffc__,
1269 "base class %q#T has a non-virtual destructor", basetype);
1271 /* If the base class doesn't have copy constructors or
1272 assignment operators that take const references, then the
1273 derived class cannot have such a member automatically
1275 if (! TYPE_HAS_CONST_INIT_REF (basetype))
1276 *cant_have_const_ctor_p = 1;
1277 if (TYPE_HAS_ASSIGN_REF (basetype)
1278 && !TYPE_HAS_CONST_ASSIGN_REF (basetype))
1279 *no_const_asn_ref_p = 1;
1281 if (BINFO_VIRTUAL_P (base_binfo))
1282 /* A virtual base does not effect nearly emptiness. */
1284 else if (CLASSTYPE_NEARLY_EMPTY_P (basetype))
1286 if (seen_non_virtual_nearly_empty_base_p)
1287 /* And if there is more than one nearly empty base, then the
1288 derived class is not nearly empty either. */
1289 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1291 /* Remember we've seen one. */
1292 seen_non_virtual_nearly_empty_base_p = 1;
1294 else if (!is_empty_class (basetype))
1295 /* If the base class is not empty or nearly empty, then this
1296 class cannot be nearly empty. */
1297 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
1299 /* A lot of properties from the bases also apply to the derived
1301 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype);
1302 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
1303 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype);
1304 TYPE_HAS_COMPLEX_ASSIGN_REF (t)
1305 |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype);
1306 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype);
1307 TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
1308 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t)
1309 |= CLASSTYPE_CONTAINS_EMPTY_CLASS_P (basetype);
1310 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (basetype);
1314 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1315 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1316 that have had a nearly-empty virtual primary base stolen by some
1317 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1321 determine_primary_bases (tree t)
1324 tree primary = NULL_TREE;
1325 tree type_binfo = TYPE_BINFO (t);
1328 /* Determine the primary bases of our bases. */
1329 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1330 base_binfo = TREE_CHAIN (base_binfo))
1332 tree primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (base_binfo));
1334 /* See if we're the non-virtual primary of our inheritance
1336 if (!BINFO_VIRTUAL_P (base_binfo))
1338 tree parent = BINFO_INHERITANCE_CHAIN (base_binfo);
1339 tree parent_primary = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (parent));
1342 && SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
1343 BINFO_TYPE (parent_primary)))
1344 /* We are the primary binfo. */
1345 BINFO_PRIMARY_P (base_binfo) = 1;
1347 /* Determine if we have a virtual primary base, and mark it so.
1349 if (primary && BINFO_VIRTUAL_P (primary))
1351 tree this_primary = copied_binfo (primary, base_binfo);
1353 if (BINFO_PRIMARY_P (this_primary))
1354 /* Someone already claimed this base. */
1355 BINFO_LOST_PRIMARY_P (base_binfo) = 1;
1360 BINFO_PRIMARY_P (this_primary) = 1;
1361 BINFO_INHERITANCE_CHAIN (this_primary) = base_binfo;
1363 /* A virtual binfo might have been copied from within
1364 another hierarchy. As we're about to use it as a
1365 primary base, make sure the offsets match. */
1366 delta = size_diffop (convert (ssizetype,
1367 BINFO_OFFSET (base_binfo)),
1369 BINFO_OFFSET (this_primary)));
1371 propagate_binfo_offsets (this_primary, delta);
1376 /* First look for a dynamic direct non-virtual base. */
1377 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, base_binfo); i++)
1379 tree basetype = BINFO_TYPE (base_binfo);
1381 if (TYPE_CONTAINS_VPTR_P (basetype) && !BINFO_VIRTUAL_P (base_binfo))
1383 primary = base_binfo;
1388 /* A "nearly-empty" virtual base class can be the primary base
1389 class, if no non-virtual polymorphic base can be found. Look for
1390 a nearly-empty virtual dynamic base that is not already a primary
1391 base of something in the hierarchy. If there is no such base,
1392 just pick the first nearly-empty virtual base. */
1394 for (base_binfo = TREE_CHAIN (type_binfo); base_binfo;
1395 base_binfo = TREE_CHAIN (base_binfo))
1396 if (BINFO_VIRTUAL_P (base_binfo)
1397 && CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (base_binfo)))
1399 if (!BINFO_PRIMARY_P (base_binfo))
1401 /* Found one that is not primary. */
1402 primary = base_binfo;
1406 /* Remember the first candidate. */
1407 primary = base_binfo;
1411 /* If we've got a primary base, use it. */
1414 tree basetype = BINFO_TYPE (primary);
1416 CLASSTYPE_PRIMARY_BINFO (t) = primary;
1417 if (BINFO_PRIMARY_P (primary))
1418 /* We are stealing a primary base. */
1419 BINFO_LOST_PRIMARY_P (BINFO_INHERITANCE_CHAIN (primary)) = 1;
1420 BINFO_PRIMARY_P (primary) = 1;
1421 if (BINFO_VIRTUAL_P (primary))
1425 BINFO_INHERITANCE_CHAIN (primary) = type_binfo;
1426 /* A virtual binfo might have been copied from within
1427 another hierarchy. As we're about to use it as a primary
1428 base, make sure the offsets match. */
1429 delta = size_diffop (ssize_int (0),
1430 convert (ssizetype, BINFO_OFFSET (primary)));
1432 propagate_binfo_offsets (primary, delta);
1435 primary = TYPE_BINFO (basetype);
1437 TYPE_VFIELD (t) = TYPE_VFIELD (basetype);
1438 BINFO_VTABLE (type_binfo) = BINFO_VTABLE (primary);
1439 BINFO_VIRTUALS (type_binfo) = BINFO_VIRTUALS (primary);
1443 /* Set memoizing fields and bits of T (and its variants) for later
1447 finish_struct_bits (tree t)
1451 /* Fix up variants (if any). */
1452 for (variants = TYPE_NEXT_VARIANT (t);
1454 variants = TYPE_NEXT_VARIANT (variants))
1456 /* These fields are in the _TYPE part of the node, not in
1457 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1458 TYPE_HAS_USER_CONSTRUCTOR (variants) = TYPE_HAS_USER_CONSTRUCTOR (t);
1459 TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t);
1460 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants)
1461 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
1463 TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t);
1465 TYPE_BINFO (variants) = TYPE_BINFO (t);
1467 /* Copy whatever these are holding today. */
1468 TYPE_VFIELD (variants) = TYPE_VFIELD (t);
1469 TYPE_METHODS (variants) = TYPE_METHODS (t);
1470 TYPE_FIELDS (variants) = TYPE_FIELDS (t);
1472 /* All variants of a class have the same attributes. */
1473 TYPE_ATTRIBUTES (variants) = TYPE_ATTRIBUTES (t);
1476 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) && TYPE_POLYMORPHIC_P (t))
1477 /* For a class w/o baseclasses, 'finish_struct' has set
1478 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1479 Similarly for a class whose base classes do not have vtables.
1480 When neither of these is true, we might have removed abstract
1481 virtuals (by providing a definition), added some (by declaring
1482 new ones), or redeclared ones from a base class. We need to
1483 recalculate what's really an abstract virtual at this point (by
1484 looking in the vtables). */
1485 get_pure_virtuals (t);
1487 /* If this type has a copy constructor or a destructor, force its
1488 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1489 nonzero. This will cause it to be passed by invisible reference
1490 and prevent it from being returned in a register. */
1491 if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
1494 DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode;
1495 for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants))
1497 SET_TYPE_MODE (variants, BLKmode);
1498 TREE_ADDRESSABLE (variants) = 1;
1503 /* Issue warnings about T having private constructors, but no friends,
1506 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1507 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1508 non-private static member functions. */
1511 maybe_warn_about_overly_private_class (tree t)
1513 int has_member_fn = 0;
1514 int has_nonprivate_method = 0;
1517 if (!warn_ctor_dtor_privacy
1518 /* If the class has friends, those entities might create and
1519 access instances, so we should not warn. */
1520 || (CLASSTYPE_FRIEND_CLASSES (t)
1521 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))
1522 /* We will have warned when the template was declared; there's
1523 no need to warn on every instantiation. */
1524 || CLASSTYPE_TEMPLATE_INSTANTIATION (t))
1525 /* There's no reason to even consider warning about this
1529 /* We only issue one warning, if more than one applies, because
1530 otherwise, on code like:
1533 // Oops - forgot `public:'
1539 we warn several times about essentially the same problem. */
1541 /* Check to see if all (non-constructor, non-destructor) member
1542 functions are private. (Since there are no friends or
1543 non-private statics, we can't ever call any of the private member
1545 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
1546 /* We're not interested in compiler-generated methods; they don't
1547 provide any way to call private members. */
1548 if (!DECL_ARTIFICIAL (fn))
1550 if (!TREE_PRIVATE (fn))
1552 if (DECL_STATIC_FUNCTION_P (fn))
1553 /* A non-private static member function is just like a
1554 friend; it can create and invoke private member
1555 functions, and be accessed without a class
1559 has_nonprivate_method = 1;
1560 /* Keep searching for a static member function. */
1562 else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn))
1566 if (!has_nonprivate_method && has_member_fn)
1568 /* There are no non-private methods, and there's at least one
1569 private member function that isn't a constructor or
1570 destructor. (If all the private members are
1571 constructors/destructors we want to use the code below that
1572 issues error messages specifically referring to
1573 constructors/destructors.) */
1575 tree binfo = TYPE_BINFO (t);
1577 for (i = 0; i != BINFO_N_BASE_BINFOS (binfo); i++)
1578 if (BINFO_BASE_ACCESS (binfo, i) != access_private_node)
1580 has_nonprivate_method = 1;
1583 if (!has_nonprivate_method)
1585 warning (OPT_Wctor_dtor_privacy,
1586 "all member functions in class %qT are private", t);
1591 /* Even if some of the member functions are non-private, the class
1592 won't be useful for much if all the constructors or destructors
1593 are private: such an object can never be created or destroyed. */
1594 fn = CLASSTYPE_DESTRUCTORS (t);
1595 if (fn && TREE_PRIVATE (fn))
1597 warning (OPT_Wctor_dtor_privacy,
1598 "%q#T only defines a private destructor and has no friends",
1603 /* Warn about classes that have private constructors and no friends. */
1604 if (TYPE_HAS_USER_CONSTRUCTOR (t)
1605 /* Implicitly generated constructors are always public. */
1606 && (!CLASSTYPE_LAZY_DEFAULT_CTOR (t)
1607 || !CLASSTYPE_LAZY_COPY_CTOR (t)))
1609 int nonprivate_ctor = 0;
1611 /* If a non-template class does not define a copy
1612 constructor, one is defined for it, enabling it to avoid
1613 this warning. For a template class, this does not
1614 happen, and so we would normally get a warning on:
1616 template <class T> class C { private: C(); };
1618 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1619 complete non-template or fully instantiated classes have this
1621 if (!TYPE_HAS_INIT_REF (t))
1622 nonprivate_ctor = 1;
1624 for (fn = CLASSTYPE_CONSTRUCTORS (t); fn; fn = OVL_NEXT (fn))
1626 tree ctor = OVL_CURRENT (fn);
1627 /* Ideally, we wouldn't count copy constructors (or, in
1628 fact, any constructor that takes an argument of the
1629 class type as a parameter) because such things cannot
1630 be used to construct an instance of the class unless
1631 you already have one. But, for now at least, we're
1633 if (! TREE_PRIVATE (ctor))
1635 nonprivate_ctor = 1;
1640 if (nonprivate_ctor == 0)
1642 warning (OPT_Wctor_dtor_privacy,
1643 "%q#T only defines private constructors and has no friends",
1651 gt_pointer_operator new_value;
1655 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1658 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;
1663 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1665 if (*m1 == NULL_TREE)
1667 if (*m2 == NULL_TREE)
1669 if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2)))
1674 /* This routine compares two fields like method_name_cmp but using the
1675 pointer operator in resort_field_decl_data. */
1678 resort_method_name_cmp (const void* m1_p, const void* m2_p)
1680 const tree *const m1 = (const tree *) m1_p;
1681 const tree *const m2 = (const tree *) m2_p;
1682 if (*m1 == NULL_TREE && *m2 == NULL_TREE)
1684 if (*m1 == NULL_TREE)
1686 if (*m2 == NULL_TREE)
1689 tree d1 = DECL_NAME (OVL_CURRENT (*m1));
1690 tree d2 = DECL_NAME (OVL_CURRENT (*m2));
1691 resort_data.new_value (&d1, resort_data.cookie);
1692 resort_data.new_value (&d2, resort_data.cookie);
1699 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1702 resort_type_method_vec (void* obj,
1703 void* orig_obj ATTRIBUTE_UNUSED ,
1704 gt_pointer_operator new_value,
1707 VEC(tree,gc) *method_vec = (VEC(tree,gc) *) obj;
1708 int len = VEC_length (tree, method_vec);
1712 /* The type conversion ops have to live at the front of the vec, so we
1714 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1715 VEC_iterate (tree, method_vec, slot, fn);
1717 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1722 resort_data.new_value = new_value;
1723 resort_data.cookie = cookie;
1724 qsort (VEC_address (tree, method_vec) + slot, len - slot, sizeof (tree),
1725 resort_method_name_cmp);
1729 /* Warn about duplicate methods in fn_fields.
1731 Sort methods that are not special (i.e., constructors, destructors,
1732 and type conversion operators) so that we can find them faster in
1736 finish_struct_methods (tree t)
1739 VEC(tree,gc) *method_vec;
1742 method_vec = CLASSTYPE_METHOD_VEC (t);
1746 len = VEC_length (tree, method_vec);
1748 /* Clear DECL_IN_AGGR_P for all functions. */
1749 for (fn_fields = TYPE_METHODS (t); fn_fields;
1750 fn_fields = TREE_CHAIN (fn_fields))
1751 DECL_IN_AGGR_P (fn_fields) = 0;
1753 /* Issue warnings about private constructors and such. If there are
1754 no methods, then some public defaults are generated. */
1755 maybe_warn_about_overly_private_class (t);
1757 /* The type conversion ops have to live at the front of the vec, so we
1759 for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT;
1760 VEC_iterate (tree, method_vec, slot, fn_fields);
1762 if (!DECL_CONV_FN_P (OVL_CURRENT (fn_fields)))
1765 qsort (VEC_address (tree, method_vec) + slot,
1766 len-slot, sizeof (tree), method_name_cmp);
1769 /* Make BINFO's vtable have N entries, including RTTI entries,
1770 vbase and vcall offsets, etc. Set its type and call the back end
1774 layout_vtable_decl (tree binfo, int n)
1779 atype = build_cplus_array_type (vtable_entry_type,
1780 build_index_type (size_int (n - 1)));
1781 layout_type (atype);
1783 /* We may have to grow the vtable. */
1784 vtable = get_vtbl_decl_for_binfo (binfo);
1785 if (!same_type_p (TREE_TYPE (vtable), atype))
1787 TREE_TYPE (vtable) = atype;
1788 DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE;
1789 layout_decl (vtable, 0);
1793 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1794 have the same signature. */
1797 same_signature_p (const_tree fndecl, const_tree base_fndecl)
1799 /* One destructor overrides another if they are the same kind of
1801 if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl)
1802 && special_function_p (base_fndecl) == special_function_p (fndecl))
1804 /* But a non-destructor never overrides a destructor, nor vice
1805 versa, nor do different kinds of destructors override
1806 one-another. For example, a complete object destructor does not
1807 override a deleting destructor. */
1808 if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl))
1811 if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)
1812 || (DECL_CONV_FN_P (fndecl)
1813 && DECL_CONV_FN_P (base_fndecl)
1814 && same_type_p (DECL_CONV_FN_TYPE (fndecl),
1815 DECL_CONV_FN_TYPE (base_fndecl))))
1817 tree types, base_types;
1818 types = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1819 base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl));
1820 if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types)))
1821 == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types))))
1822 && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types)))
1828 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1832 base_derived_from (tree derived, tree base)
1836 for (probe = base; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1838 if (probe == derived)
1840 else if (BINFO_VIRTUAL_P (probe))
1841 /* If we meet a virtual base, we can't follow the inheritance
1842 any more. See if the complete type of DERIVED contains
1843 such a virtual base. */
1844 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
1850 typedef struct find_final_overrider_data_s {
1851 /* The function for which we are trying to find a final overrider. */
1853 /* The base class in which the function was declared. */
1854 tree declaring_base;
1855 /* The candidate overriders. */
1857 /* Path to most derived. */
1858 VEC(tree,heap) *path;
1859 } find_final_overrider_data;
1861 /* Add the overrider along the current path to FFOD->CANDIDATES.
1862 Returns true if an overrider was found; false otherwise. */
1865 dfs_find_final_overrider_1 (tree binfo,
1866 find_final_overrider_data *ffod,
1871 /* If BINFO is not the most derived type, try a more derived class.
1872 A definition there will overrider a definition here. */
1876 if (dfs_find_final_overrider_1
1877 (VEC_index (tree, ffod->path, depth), ffod, depth))
1881 method = look_for_overrides_here (BINFO_TYPE (binfo), ffod->fn);
1884 tree *candidate = &ffod->candidates;
1886 /* Remove any candidates overridden by this new function. */
1889 /* If *CANDIDATE overrides METHOD, then METHOD
1890 cannot override anything else on the list. */
1891 if (base_derived_from (TREE_VALUE (*candidate), binfo))
1893 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1894 if (base_derived_from (binfo, TREE_VALUE (*candidate)))
1895 *candidate = TREE_CHAIN (*candidate);
1897 candidate = &TREE_CHAIN (*candidate);
1900 /* Add the new function. */
1901 ffod->candidates = tree_cons (method, binfo, ffod->candidates);
1908 /* Called from find_final_overrider via dfs_walk. */
1911 dfs_find_final_overrider_pre (tree binfo, void *data)
1913 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1915 if (binfo == ffod->declaring_base)
1916 dfs_find_final_overrider_1 (binfo, ffod, VEC_length (tree, ffod->path));
1917 VEC_safe_push (tree, heap, ffod->path, binfo);
1923 dfs_find_final_overrider_post (tree binfo ATTRIBUTE_UNUSED, void *data)
1925 find_final_overrider_data *ffod = (find_final_overrider_data *) data;
1926 VEC_pop (tree, ffod->path);
1931 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1932 FN and whose TREE_VALUE is the binfo for the base where the
1933 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1934 DERIVED) is the base object in which FN is declared. */
1937 find_final_overrider (tree derived, tree binfo, tree fn)
1939 find_final_overrider_data ffod;
1941 /* Getting this right is a little tricky. This is valid:
1943 struct S { virtual void f (); };
1944 struct T { virtual void f (); };
1945 struct U : public S, public T { };
1947 even though calling `f' in `U' is ambiguous. But,
1949 struct R { virtual void f(); };
1950 struct S : virtual public R { virtual void f (); };
1951 struct T : virtual public R { virtual void f (); };
1952 struct U : public S, public T { };
1954 is not -- there's no way to decide whether to put `S::f' or
1955 `T::f' in the vtable for `R'.
1957 The solution is to look at all paths to BINFO. If we find
1958 different overriders along any two, then there is a problem. */
1959 if (DECL_THUNK_P (fn))
1960 fn = THUNK_TARGET (fn);
1962 /* Determine the depth of the hierarchy. */
1964 ffod.declaring_base = binfo;
1965 ffod.candidates = NULL_TREE;
1966 ffod.path = VEC_alloc (tree, heap, 30);
1968 dfs_walk_all (derived, dfs_find_final_overrider_pre,
1969 dfs_find_final_overrider_post, &ffod);
1971 VEC_free (tree, heap, ffod.path);
1973 /* If there was no winner, issue an error message. */
1974 if (!ffod.candidates || TREE_CHAIN (ffod.candidates))
1975 return error_mark_node;
1977 return ffod.candidates;
1980 /* Return the index of the vcall offset for FN when TYPE is used as a
1984 get_vcall_index (tree fn, tree type)
1986 VEC(tree_pair_s,gc) *indices = CLASSTYPE_VCALL_INDICES (type);
1990 for (ix = 0; VEC_iterate (tree_pair_s, indices, ix, p); ix++)
1991 if ((DECL_DESTRUCTOR_P (fn) && DECL_DESTRUCTOR_P (p->purpose))
1992 || same_signature_p (fn, p->purpose))
1995 /* There should always be an appropriate index. */
1999 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2000 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
2001 corresponding position in the BINFO_VIRTUALS list. */
2004 update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
2012 tree overrider_fn, overrider_target;
2013 tree target_fn = DECL_THUNK_P (fn) ? THUNK_TARGET (fn) : fn;
2014 tree over_return, base_return;
2017 /* Find the nearest primary base (possibly binfo itself) which defines
2018 this function; this is the class the caller will convert to when
2019 calling FN through BINFO. */
2020 for (b = binfo; ; b = get_primary_binfo (b))
2023 if (look_for_overrides_here (BINFO_TYPE (b), target_fn))
2026 /* The nearest definition is from a lost primary. */
2027 if (BINFO_LOST_PRIMARY_P (b))
2032 /* Find the final overrider. */
2033 overrider = find_final_overrider (TYPE_BINFO (t), b, target_fn);
2034 if (overrider == error_mark_node)
2036 error ("no unique final overrider for %qD in %qT", target_fn, t);
2039 overrider_target = overrider_fn = TREE_PURPOSE (overrider);
2041 /* Check for adjusting covariant return types. */
2042 over_return = TREE_TYPE (TREE_TYPE (overrider_target));
2043 base_return = TREE_TYPE (TREE_TYPE (target_fn));
2045 if (POINTER_TYPE_P (over_return)
2046 && TREE_CODE (over_return) == TREE_CODE (base_return)
2047 && CLASS_TYPE_P (TREE_TYPE (over_return))
2048 && CLASS_TYPE_P (TREE_TYPE (base_return))
2049 /* If the overrider is invalid, don't even try. */
2050 && !DECL_INVALID_OVERRIDER_P (overrider_target))
2052 /* If FN is a covariant thunk, we must figure out the adjustment
2053 to the final base FN was converting to. As OVERRIDER_TARGET might
2054 also be converting to the return type of FN, we have to
2055 combine the two conversions here. */
2056 tree fixed_offset, virtual_offset;
2058 over_return = TREE_TYPE (over_return);
2059 base_return = TREE_TYPE (base_return);
2061 if (DECL_THUNK_P (fn))
2063 gcc_assert (DECL_RESULT_THUNK_P (fn));
2064 fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn));
2065 virtual_offset = THUNK_VIRTUAL_OFFSET (fn);
2068 fixed_offset = virtual_offset = NULL_TREE;
2071 /* Find the equivalent binfo within the return type of the
2072 overriding function. We will want the vbase offset from
2074 virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
2076 else if (!same_type_ignoring_top_level_qualifiers_p
2077 (over_return, base_return))
2079 /* There was no existing virtual thunk (which takes
2080 precedence). So find the binfo of the base function's
2081 return type within the overriding function's return type.
2082 We cannot call lookup base here, because we're inside a
2083 dfs_walk, and will therefore clobber the BINFO_MARKED
2084 flags. Fortunately we know the covariancy is valid (it
2085 has already been checked), so we can just iterate along
2086 the binfos, which have been chained in inheritance graph
2087 order. Of course it is lame that we have to repeat the
2088 search here anyway -- we should really be caching pieces
2089 of the vtable and avoiding this repeated work. */
2090 tree thunk_binfo, base_binfo;
2092 /* Find the base binfo within the overriding function's
2093 return type. We will always find a thunk_binfo, except
2094 when the covariancy is invalid (which we will have
2095 already diagnosed). */
2096 for (base_binfo = TYPE_BINFO (base_return),
2097 thunk_binfo = TYPE_BINFO (over_return);
2099 thunk_binfo = TREE_CHAIN (thunk_binfo))
2100 if (SAME_BINFO_TYPE_P (BINFO_TYPE (thunk_binfo),
2101 BINFO_TYPE (base_binfo)))
2104 /* See if virtual inheritance is involved. */
2105 for (virtual_offset = thunk_binfo;
2107 virtual_offset = BINFO_INHERITANCE_CHAIN (virtual_offset))
2108 if (BINFO_VIRTUAL_P (virtual_offset))
2112 || (thunk_binfo && !BINFO_OFFSET_ZEROP (thunk_binfo)))
2114 tree offset = convert (ssizetype, BINFO_OFFSET (thunk_binfo));
2118 /* We convert via virtual base. Adjust the fixed
2119 offset to be from there. */
2120 offset = size_diffop
2122 (ssizetype, BINFO_OFFSET (virtual_offset)));
2125 /* There was an existing fixed offset, this must be
2126 from the base just converted to, and the base the
2127 FN was thunking to. */
2128 fixed_offset = size_binop (PLUS_EXPR, fixed_offset, offset);
2130 fixed_offset = offset;
2134 if (fixed_offset || virtual_offset)
2135 /* Replace the overriding function with a covariant thunk. We
2136 will emit the overriding function in its own slot as
2138 overrider_fn = make_thunk (overrider_target, /*this_adjusting=*/0,
2139 fixed_offset, virtual_offset);
2142 gcc_assert (DECL_INVALID_OVERRIDER_P (overrider_target) ||
2143 !DECL_THUNK_P (fn));
2145 /* Assume that we will produce a thunk that convert all the way to
2146 the final overrider, and not to an intermediate virtual base. */
2147 virtual_base = NULL_TREE;
2149 /* See if we can convert to an intermediate virtual base first, and then
2150 use the vcall offset located there to finish the conversion. */
2151 for (; b; b = BINFO_INHERITANCE_CHAIN (b))
2153 /* If we find the final overrider, then we can stop
2155 if (SAME_BINFO_TYPE_P (BINFO_TYPE (b),
2156 BINFO_TYPE (TREE_VALUE (overrider))))
2159 /* If we find a virtual base, and we haven't yet found the
2160 overrider, then there is a virtual base between the
2161 declaring base (first_defn) and the final overrider. */
2162 if (BINFO_VIRTUAL_P (b))
2169 if (overrider_fn != overrider_target && !virtual_base)
2171 /* The ABI specifies that a covariant thunk includes a mangling
2172 for a this pointer adjustment. This-adjusting thunks that
2173 override a function from a virtual base have a vcall
2174 adjustment. When the virtual base in question is a primary
2175 virtual base, we know the adjustments are zero, (and in the
2176 non-covariant case, we would not use the thunk).
2177 Unfortunately we didn't notice this could happen, when
2178 designing the ABI and so never mandated that such a covariant
2179 thunk should be emitted. Because we must use the ABI mandated
2180 name, we must continue searching from the binfo where we
2181 found the most recent definition of the function, towards the
2182 primary binfo which first introduced the function into the
2183 vtable. If that enters a virtual base, we must use a vcall
2184 this-adjusting thunk. Bleah! */
2185 tree probe = first_defn;
2187 while ((probe = get_primary_binfo (probe))
2188 && (unsigned) list_length (BINFO_VIRTUALS (probe)) > ix)
2189 if (BINFO_VIRTUAL_P (probe))
2190 virtual_base = probe;
2193 /* Even if we find a virtual base, the correct delta is
2194 between the overrider and the binfo we're building a vtable
2196 goto virtual_covariant;
2199 /* Compute the constant adjustment to the `this' pointer. The
2200 `this' pointer, when this function is called, will point at BINFO
2201 (or one of its primary bases, which are at the same offset). */
2203 /* The `this' pointer needs to be adjusted from the declaration to
2204 the nearest virtual base. */
2205 delta = size_diffop (convert (ssizetype, BINFO_OFFSET (virtual_base)),
2206 convert (ssizetype, BINFO_OFFSET (first_defn)));
2208 /* If the nearest definition is in a lost primary, we don't need an
2209 entry in our vtable. Except possibly in a constructor vtable,
2210 if we happen to get our primary back. In that case, the offset
2211 will be zero, as it will be a primary base. */
2212 delta = size_zero_node;
2214 /* The `this' pointer needs to be adjusted from pointing to
2215 BINFO to pointing at the base where the final overrider
2218 delta = size_diffop (convert (ssizetype,
2219 BINFO_OFFSET (TREE_VALUE (overrider))),
2220 convert (ssizetype, BINFO_OFFSET (binfo)));
2222 modify_vtable_entry (t, binfo, overrider_fn, delta, virtuals);
2225 BV_VCALL_INDEX (*virtuals)
2226 = get_vcall_index (overrider_target, BINFO_TYPE (virtual_base));
2228 BV_VCALL_INDEX (*virtuals) = NULL_TREE;
2231 /* Called from modify_all_vtables via dfs_walk. */
2234 dfs_modify_vtables (tree binfo, void* data)
2236 tree t = (tree) data;
2241 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
2242 /* A base without a vtable needs no modification, and its bases
2243 are uninteresting. */
2244 return dfs_skip_bases;
2246 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t)
2247 && !CLASSTYPE_HAS_PRIMARY_BASE_P (t))
2248 /* Don't do the primary vtable, if it's new. */
2251 if (BINFO_PRIMARY_P (binfo) && !BINFO_VIRTUAL_P (binfo))
2252 /* There's no need to modify the vtable for a non-virtual primary
2253 base; we're not going to use that vtable anyhow. We do still
2254 need to do this for virtual primary bases, as they could become
2255 non-primary in a construction vtable. */
2258 make_new_vtable (t, binfo);
2260 /* Now, go through each of the virtual functions in the virtual
2261 function table for BINFO. Find the final overrider, and update
2262 the BINFO_VIRTUALS list appropriately. */
2263 for (ix = 0, virtuals = BINFO_VIRTUALS (binfo),
2264 old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
2266 ix++, virtuals = TREE_CHAIN (virtuals),
2267 old_virtuals = TREE_CHAIN (old_virtuals))
2268 update_vtable_entry_for_fn (t,
2270 BV_FN (old_virtuals),
2276 /* Update all of the primary and secondary vtables for T. Create new
2277 vtables as required, and initialize their RTTI information. Each
2278 of the functions in VIRTUALS is declared in T and may override a
2279 virtual function from a base class; find and modify the appropriate
2280 entries to point to the overriding functions. Returns a list, in
2281 declaration order, of the virtual functions that are declared in T,
2282 but do not appear in the primary base class vtable, and which
2283 should therefore be appended to the end of the vtable for T. */
2286 modify_all_vtables (tree t, tree virtuals)
2288 tree binfo = TYPE_BINFO (t);
2291 /* Update all of the vtables. */
2292 dfs_walk_once (binfo, dfs_modify_vtables, NULL, t);
2294 /* Add virtual functions not already in our primary vtable. These
2295 will be both those introduced by this class, and those overridden
2296 from secondary bases. It does not include virtuals merely
2297 inherited from secondary bases. */
2298 for (fnsp = &virtuals; *fnsp; )
2300 tree fn = TREE_VALUE (*fnsp);
2302 if (!value_member (fn, BINFO_VIRTUALS (binfo))
2303 || DECL_VINDEX (fn) == error_mark_node)
2305 /* We don't need to adjust the `this' pointer when
2306 calling this function. */
2307 BV_DELTA (*fnsp) = integer_zero_node;
2308 BV_VCALL_INDEX (*fnsp) = NULL_TREE;
2310 /* This is a function not already in our vtable. Keep it. */
2311 fnsp = &TREE_CHAIN (*fnsp);
2314 /* We've already got an entry for this function. Skip it. */
2315 *fnsp = TREE_CHAIN (*fnsp);
2321 /* Get the base virtual function declarations in T that have the
2325 get_basefndecls (tree name, tree t)
2328 tree base_fndecls = NULL_TREE;
2329 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
2332 /* Find virtual functions in T with the indicated NAME. */
2333 i = lookup_fnfields_1 (t, name);
2335 for (methods = VEC_index (tree, CLASSTYPE_METHOD_VEC (t), i);
2337 methods = OVL_NEXT (methods))
2339 tree method = OVL_CURRENT (methods);
2341 if (TREE_CODE (method) == FUNCTION_DECL
2342 && DECL_VINDEX (method))
2343 base_fndecls = tree_cons (NULL_TREE, method, base_fndecls);
2347 return base_fndecls;
2349 for (i = 0; i < n_baseclasses; i++)
2351 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (t), i));
2352 base_fndecls = chainon (get_basefndecls (name, basetype),
2356 return base_fndecls;
2359 /* If this declaration supersedes the declaration of
2360 a method declared virtual in the base class, then
2361 mark this field as being virtual as well. */
2364 check_for_override (tree decl, tree ctype)
2366 if (TREE_CODE (decl) == TEMPLATE_DECL)
2367 /* In [temp.mem] we have:
2369 A specialization of a member function template does not
2370 override a virtual function from a base class. */
2372 if ((DECL_DESTRUCTOR_P (decl)
2373 || IDENTIFIER_VIRTUAL_P (DECL_NAME (decl))
2374 || DECL_CONV_FN_P (decl))
2375 && look_for_overrides (ctype, decl)
2376 && !DECL_STATIC_FUNCTION_P (decl))
2377 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2378 the error_mark_node so that we know it is an overriding
2380 DECL_VINDEX (decl) = decl;
2382 if (DECL_VIRTUAL_P (decl))
2384 if (!DECL_VINDEX (decl))
2385 DECL_VINDEX (decl) = error_mark_node;
2386 IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1;
2390 /* Warn about hidden virtual functions that are not overridden in t.
2391 We know that constructors and destructors don't apply. */
2394 warn_hidden (tree t)
2396 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (t);
2400 /* We go through each separately named virtual function. */
2401 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2402 VEC_iterate (tree, method_vec, i, fns);
2413 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2414 have the same name. Figure out what name that is. */
2415 name = DECL_NAME (OVL_CURRENT (fns));
2416 /* There are no possibly hidden functions yet. */
2417 base_fndecls = NULL_TREE;
2418 /* Iterate through all of the base classes looking for possibly
2419 hidden functions. */
2420 for (binfo = TYPE_BINFO (t), j = 0;
2421 BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
2423 tree basetype = BINFO_TYPE (base_binfo);
2424 base_fndecls = chainon (get_basefndecls (name, basetype),
2428 /* If there are no functions to hide, continue. */
2432 /* Remove any overridden functions. */
2433 for (fn = fns; fn; fn = OVL_NEXT (fn))
2435 fndecl = OVL_CURRENT (fn);
2436 if (DECL_VINDEX (fndecl))
2438 tree *prev = &base_fndecls;
2441 /* If the method from the base class has the same
2442 signature as the method from the derived class, it
2443 has been overridden. */
2444 if (same_signature_p (fndecl, TREE_VALUE (*prev)))
2445 *prev = TREE_CHAIN (*prev);
2447 prev = &TREE_CHAIN (*prev);
2451 /* Now give a warning for all base functions without overriders,
2452 as they are hidden. */
2453 while (base_fndecls)
2455 /* Here we know it is a hider, and no overrider exists. */
2456 warning (OPT_Woverloaded_virtual, "%q+D was hidden", TREE_VALUE (base_fndecls));
2457 warning (OPT_Woverloaded_virtual, " by %q+D", fns);
2458 base_fndecls = TREE_CHAIN (base_fndecls);
2463 /* Check for things that are invalid. There are probably plenty of other
2464 things we should check for also. */
2467 finish_struct_anon (tree t)
2471 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2473 if (TREE_STATIC (field))
2475 if (TREE_CODE (field) != FIELD_DECL)
2478 if (DECL_NAME (field) == NULL_TREE
2479 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2481 bool is_union = TREE_CODE (TREE_TYPE (field)) == UNION_TYPE;
2482 tree elt = TYPE_FIELDS (TREE_TYPE (field));
2483 for (; elt; elt = TREE_CHAIN (elt))
2485 /* We're generally only interested in entities the user
2486 declared, but we also find nested classes by noticing
2487 the TYPE_DECL that we create implicitly. You're
2488 allowed to put one anonymous union inside another,
2489 though, so we explicitly tolerate that. We use
2490 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2491 we also allow unnamed types used for defining fields. */
2492 if (DECL_ARTIFICIAL (elt)
2493 && (!DECL_IMPLICIT_TYPEDEF_P (elt)
2494 || TYPE_ANONYMOUS_P (TREE_TYPE (elt))))
2497 if (TREE_CODE (elt) != FIELD_DECL)
2500 permerror (input_location, "%q+#D invalid; an anonymous union can "
2501 "only have non-static data members", elt);
2503 permerror (input_location, "%q+#D invalid; an anonymous struct can "
2504 "only have non-static data members", elt);
2508 if (TREE_PRIVATE (elt))
2511 permerror (input_location, "private member %q+#D in anonymous union", elt);
2513 permerror (input_location, "private member %q+#D in anonymous struct", elt);
2515 else if (TREE_PROTECTED (elt))
2518 permerror (input_location, "protected member %q+#D in anonymous union", elt);
2520 permerror (input_location, "protected member %q+#D in anonymous struct", elt);
2523 TREE_PRIVATE (elt) = TREE_PRIVATE (field);
2524 TREE_PROTECTED (elt) = TREE_PROTECTED (field);
2530 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2531 will be used later during class template instantiation.
2532 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2533 a non-static member data (FIELD_DECL), a member function
2534 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2535 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2536 When FRIEND_P is nonzero, T is either a friend class
2537 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2538 (FUNCTION_DECL, TEMPLATE_DECL). */
2541 maybe_add_class_template_decl_list (tree type, tree t, int friend_p)
2543 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2544 if (CLASSTYPE_TEMPLATE_INFO (type))
2545 CLASSTYPE_DECL_LIST (type)
2546 = tree_cons (friend_p ? NULL_TREE : type,
2547 t, CLASSTYPE_DECL_LIST (type));
2550 /* Create default constructors, assignment operators, and so forth for
2551 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2552 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2553 the class cannot have a default constructor, copy constructor
2554 taking a const reference argument, or an assignment operator taking
2555 a const reference, respectively. */
2558 add_implicitly_declared_members (tree t,
2559 int cant_have_const_cctor,
2560 int cant_have_const_assignment)
2563 if (!CLASSTYPE_DESTRUCTORS (t))
2565 /* In general, we create destructors lazily. */
2566 CLASSTYPE_LAZY_DESTRUCTOR (t) = 1;
2567 /* However, if the implicit destructor is non-trivial
2568 destructor, we sometimes have to create it at this point. */
2569 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t))
2573 if (TYPE_FOR_JAVA (t))
2574 /* If this a Java class, any non-trivial destructor is
2575 invalid, even if compiler-generated. Therefore, if the
2576 destructor is non-trivial we create it now. */
2584 /* If the implicit destructor will be virtual, then we must
2585 generate it now because (unfortunately) we do not
2586 generate virtual tables lazily. */
2587 binfo = TYPE_BINFO (t);
2588 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
2593 base_type = BINFO_TYPE (base_binfo);
2594 dtor = CLASSTYPE_DESTRUCTORS (base_type);
2595 if (dtor && DECL_VIRTUAL_P (dtor))
2603 /* If we can't get away with being lazy, generate the destructor
2606 lazily_declare_fn (sfk_destructor, t);
2612 If there is no user-declared constructor for a class, a default
2613 constructor is implicitly declared. */
2614 if (! TYPE_HAS_USER_CONSTRUCTOR (t))
2616 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 1;
2617 CLASSTYPE_LAZY_DEFAULT_CTOR (t) = 1;
2622 If a class definition does not explicitly declare a copy
2623 constructor, one is declared implicitly. */
2624 if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t))
2626 TYPE_HAS_INIT_REF (t) = 1;
2627 TYPE_HAS_CONST_INIT_REF (t) = !cant_have_const_cctor;
2628 CLASSTYPE_LAZY_COPY_CTOR (t) = 1;
2631 /* If there is no assignment operator, one will be created if and
2632 when it is needed. For now, just record whether or not the type
2633 of the parameter to the assignment operator will be a const or
2634 non-const reference. */
2635 if (!TYPE_HAS_ASSIGN_REF (t) && !TYPE_FOR_JAVA (t))
2637 TYPE_HAS_ASSIGN_REF (t) = 1;
2638 TYPE_HAS_CONST_ASSIGN_REF (t) = !cant_have_const_assignment;
2639 CLASSTYPE_LAZY_ASSIGNMENT_OP (t) = 1;
2643 /* Subroutine of finish_struct_1. Recursively count the number of fields
2644 in TYPE, including anonymous union members. */
2647 count_fields (tree fields)
2651 for (x = fields; x; x = TREE_CHAIN (x))
2653 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2654 n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x)));
2661 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2662 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2665 add_fields_to_record_type (tree fields, struct sorted_fields_type *field_vec, int idx)
2668 for (x = fields; x; x = TREE_CHAIN (x))
2670 if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x)))
2671 idx = add_fields_to_record_type (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx);
2673 field_vec->elts[idx++] = x;
2678 /* FIELD is a bit-field. We are finishing the processing for its
2679 enclosing type. Issue any appropriate messages and set appropriate
2680 flags. Returns false if an error has been diagnosed. */
2683 check_bitfield_decl (tree field)
2685 tree type = TREE_TYPE (field);
2688 /* Extract the declared width of the bitfield, which has been
2689 temporarily stashed in DECL_INITIAL. */
2690 w = DECL_INITIAL (field);
2691 gcc_assert (w != NULL_TREE);
2692 /* Remove the bit-field width indicator so that the rest of the
2693 compiler does not treat that value as an initializer. */
2694 DECL_INITIAL (field) = NULL_TREE;
2696 /* Detect invalid bit-field type. */
2697 if (!INTEGRAL_TYPE_P (type))
2699 error ("bit-field %q+#D with non-integral type", field);
2700 w = error_mark_node;
2704 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2707 /* detect invalid field size. */
2708 w = integral_constant_value (w);
2710 if (TREE_CODE (w) != INTEGER_CST)
2712 error ("bit-field %q+D width not an integer constant", field);
2713 w = error_mark_node;
2715 else if (tree_int_cst_sgn (w) < 0)
2717 error ("negative width in bit-field %q+D", field);
2718 w = error_mark_node;
2720 else if (integer_zerop (w) && DECL_NAME (field) != 0)
2722 error ("zero width for bit-field %q+D", field);
2723 w = error_mark_node;
2725 else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0
2726 && TREE_CODE (type) != ENUMERAL_TYPE
2727 && TREE_CODE (type) != BOOLEAN_TYPE)
2728 warning (0, "width of %q+D exceeds its type", field);
2729 else if (TREE_CODE (type) == ENUMERAL_TYPE
2730 && (0 > compare_tree_int (w,
2731 tree_int_cst_min_precision
2732 (TYPE_MIN_VALUE (type),
2733 TYPE_UNSIGNED (type)))
2734 || 0 > compare_tree_int (w,
2735 tree_int_cst_min_precision
2736 (TYPE_MAX_VALUE (type),
2737 TYPE_UNSIGNED (type)))))
2738 warning (0, "%q+D is too small to hold all values of %q#T", field, type);
2741 if (w != error_mark_node)
2743 DECL_SIZE (field) = convert (bitsizetype, w);
2744 DECL_BIT_FIELD (field) = 1;
2749 /* Non-bit-fields are aligned for their type. */
2750 DECL_BIT_FIELD (field) = 0;
2751 CLEAR_DECL_C_BIT_FIELD (field);
2756 /* FIELD is a non bit-field. We are finishing the processing for its
2757 enclosing type T. Issue any appropriate messages and set appropriate
2761 check_field_decl (tree field,
2763 int* cant_have_const_ctor,
2764 int* no_const_asn_ref,
2765 int* any_default_members)
2767 tree type = strip_array_types (TREE_TYPE (field));
2769 /* An anonymous union cannot contain any fields which would change
2770 the settings of CANT_HAVE_CONST_CTOR and friends. */
2771 if (ANON_UNION_TYPE_P (type))
2773 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2774 structs. So, we recurse through their fields here. */
2775 else if (ANON_AGGR_TYPE_P (type))
2779 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2780 if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field))
2781 check_field_decl (fields, t, cant_have_const_ctor,
2782 no_const_asn_ref, any_default_members);
2784 /* Check members with class type for constructors, destructors,
2786 else if (CLASS_TYPE_P (type))
2788 /* Never let anything with uninheritable virtuals
2789 make it through without complaint. */
2790 abstract_virtuals_error (field, type);
2792 if (TREE_CODE (t) == UNION_TYPE)
2794 if (TYPE_NEEDS_CONSTRUCTING (type))
2795 error ("member %q+#D with constructor not allowed in union",
2797 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
2798 error ("member %q+#D with destructor not allowed in union", field);
2799 if (TYPE_HAS_COMPLEX_ASSIGN_REF (type))
2800 error ("member %q+#D with copy assignment operator not allowed in union",
2805 TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type);
2806 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
2807 |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type);
2808 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type);
2809 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type);
2810 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_HAS_COMPLEX_DFLT (type);
2813 if (!TYPE_HAS_CONST_INIT_REF (type))
2814 *cant_have_const_ctor = 1;
2816 if (!TYPE_HAS_CONST_ASSIGN_REF (type))
2817 *no_const_asn_ref = 1;
2819 if (DECL_INITIAL (field) != NULL_TREE)
2821 /* `build_class_init_list' does not recognize
2823 if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0)
2824 error ("multiple fields in union %qT initialized", t);
2825 *any_default_members = 1;
2829 /* Check the data members (both static and non-static), class-scoped
2830 typedefs, etc., appearing in the declaration of T. Issue
2831 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2832 declaration order) of access declarations; each TREE_VALUE in this
2833 list is a USING_DECL.
2835 In addition, set the following flags:
2838 The class is empty, i.e., contains no non-static data members.
2840 CANT_HAVE_CONST_CTOR_P
2841 This class cannot have an implicitly generated copy constructor
2842 taking a const reference.
2844 CANT_HAVE_CONST_ASN_REF
2845 This class cannot have an implicitly generated assignment
2846 operator taking a const reference.
2848 All of these flags should be initialized before calling this
2851 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2852 fields can be added by adding to this chain. */
2855 check_field_decls (tree t, tree *access_decls,
2856 int *cant_have_const_ctor_p,
2857 int *no_const_asn_ref_p)
2862 int any_default_members;
2865 /* Assume there are no access declarations. */
2866 *access_decls = NULL_TREE;
2867 /* Assume this class has no pointer members. */
2868 has_pointers = false;
2869 /* Assume none of the members of this class have default
2871 any_default_members = 0;
2873 for (field = &TYPE_FIELDS (t); *field; field = next)
2876 tree type = TREE_TYPE (x);
2878 next = &TREE_CHAIN (x);
2880 if (TREE_CODE (x) == USING_DECL)
2882 /* Prune the access declaration from the list of fields. */
2883 *field = TREE_CHAIN (x);
2885 /* Save the access declarations for our caller. */
2886 *access_decls = tree_cons (NULL_TREE, x, *access_decls);
2888 /* Since we've reset *FIELD there's no reason to skip to the
2894 if (TREE_CODE (x) == TYPE_DECL
2895 || TREE_CODE (x) == TEMPLATE_DECL)
2898 /* If we've gotten this far, it's a data member, possibly static,
2899 or an enumerator. */
2900 DECL_CONTEXT (x) = t;
2902 /* When this goes into scope, it will be a non-local reference. */
2903 DECL_NONLOCAL (x) = 1;
2905 if (TREE_CODE (t) == UNION_TYPE)
2909 If a union contains a static data member, or a member of
2910 reference type, the program is ill-formed. */
2911 if (TREE_CODE (x) == VAR_DECL)
2913 error ("%q+D may not be static because it is a member of a union", x);
2916 if (TREE_CODE (type) == REFERENCE_TYPE)
2918 error ("%q+D may not have reference type %qT because"
2919 " it is a member of a union",
2925 /* Perform error checking that did not get done in
2927 if (TREE_CODE (type) == FUNCTION_TYPE)
2929 error ("field %q+D invalidly declared function type", x);
2930 type = build_pointer_type (type);
2931 TREE_TYPE (x) = type;
2933 else if (TREE_CODE (type) == METHOD_TYPE)
2935 error ("field %q+D invalidly declared method type", x);
2936 type = build_pointer_type (type);
2937 TREE_TYPE (x) = type;
2940 if (type == error_mark_node)
2943 if (TREE_CODE (x) == CONST_DECL || TREE_CODE (x) == VAR_DECL)
2946 /* Now it can only be a FIELD_DECL. */
2948 if (TREE_PRIVATE (x) || TREE_PROTECTED (x))
2949 CLASSTYPE_NON_AGGREGATE (t) = 1;
2951 /* If this is of reference type, check if it needs an init. */
2952 if (TREE_CODE (type) == REFERENCE_TYPE)
2954 CLASSTYPE_NON_POD_P (t) = 1;
2955 if (DECL_INITIAL (x) == NULL_TREE)
2956 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
2958 /* ARM $12.6.2: [A member initializer list] (or, for an
2959 aggregate, initialization by a brace-enclosed list) is the
2960 only way to initialize nonstatic const and reference
2962 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
2965 type = strip_array_types (type);
2967 if (TYPE_PACKED (t))
2969 if (!pod_type_p (type) && !TYPE_PACKED (type))
2973 "ignoring packed attribute because of unpacked non-POD field %q+#D",
2977 else if (DECL_C_BIT_FIELD (x)
2978 || TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
2979 DECL_PACKED (x) = 1;
2982 if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x)))
2983 /* We don't treat zero-width bitfields as making a class
2988 /* The class is non-empty. */
2989 CLASSTYPE_EMPTY_P (t) = 0;
2990 /* The class is not even nearly empty. */
2991 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
2992 /* If one of the data members contains an empty class,
2994 if (CLASS_TYPE_P (type)
2995 && CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
2996 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
2999 /* This is used by -Weffc++ (see below). Warn only for pointers
3000 to members which might hold dynamic memory. So do not warn
3001 for pointers to functions or pointers to members. */
3002 if (TYPE_PTR_P (type)
3003 && !TYPE_PTRFN_P (type)
3004 && !TYPE_PTR_TO_MEMBER_P (type))
3005 has_pointers = true;
3007 if (CLASS_TYPE_P (type))
3009 if (CLASSTYPE_REF_FIELDS_NEED_INIT (type))
3010 SET_CLASSTYPE_REF_FIELDS_NEED_INIT (t, 1);
3011 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (type))
3012 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3015 if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type))
3016 CLASSTYPE_HAS_MUTABLE (t) = 1;
3018 if (! pod_type_p (type))
3019 /* DR 148 now allows pointers to members (which are POD themselves),
3020 to be allowed in POD structs. */
3021 CLASSTYPE_NON_POD_P (t) = 1;
3023 if (! zero_init_p (type))
3024 CLASSTYPE_NON_ZERO_INIT_P (t) = 1;
3026 /* If any field is const, the structure type is pseudo-const. */
3027 if (CP_TYPE_CONST_P (type))
3029 C_TYPE_FIELDS_READONLY (t) = 1;
3030 if (DECL_INITIAL (x) == NULL_TREE)
3031 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t, 1);
3033 /* ARM $12.6.2: [A member initializer list] (or, for an
3034 aggregate, initialization by a brace-enclosed list) is the
3035 only way to initialize nonstatic const and reference
3037 TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1;
3039 /* A field that is pseudo-const makes the structure likewise. */
3040 else if (CLASS_TYPE_P (type))
3042 C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type);
3043 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT (t,
3044 CLASSTYPE_READONLY_FIELDS_NEED_INIT (t)
3045 | CLASSTYPE_READONLY_FIELDS_NEED_INIT (type));
3048 /* Core issue 80: A nonstatic data member is required to have a
3049 different name from the class iff the class has a
3050 user-declared constructor. */
3051 if (constructor_name_p (DECL_NAME (x), t)
3052 && TYPE_HAS_USER_CONSTRUCTOR (t))
3053 permerror (input_location, "field %q+#D with same name as class", x);
3055 /* We set DECL_C_BIT_FIELD in grokbitfield.
3056 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3057 if (! DECL_C_BIT_FIELD (x) || ! check_bitfield_decl (x))
3058 check_field_decl (x, t,
3059 cant_have_const_ctor_p,
3061 &any_default_members);
3064 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3065 it should also define a copy constructor and an assignment operator to
3066 implement the correct copy semantic (deep vs shallow, etc.). As it is
3067 not feasible to check whether the constructors do allocate dynamic memory
3068 and store it within members, we approximate the warning like this:
3070 -- Warn only if there are members which are pointers
3071 -- Warn only if there is a non-trivial constructor (otherwise,
3072 there cannot be memory allocated).
3073 -- Warn only if there is a non-trivial destructor. We assume that the
3074 user at least implemented the cleanup correctly, and a destructor
3075 is needed to free dynamic memory.
3077 This seems enough for practical purposes. */
3080 && TYPE_HAS_USER_CONSTRUCTOR (t)
3081 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t)
3082 && !(TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t)))
3084 warning (OPT_Weffc__, "%q#T has pointer data members", t);
3086 if (! TYPE_HAS_INIT_REF (t))
3088 warning (OPT_Weffc__,
3089 " but does not override %<%T(const %T&)%>", t, t);
3090 if (!TYPE_HAS_ASSIGN_REF (t))
3091 warning (OPT_Weffc__, " or %<operator=(const %T&)%>", t);
3093 else if (! TYPE_HAS_ASSIGN_REF (t))
3094 warning (OPT_Weffc__,
3095 " but does not override %<operator=(const %T&)%>", t);
3098 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3100 TYPE_PACKED (t) = 0;
3102 /* Check anonymous struct/anonymous union fields. */
3103 finish_struct_anon (t);
3105 /* We've built up the list of access declarations in reverse order.
3107 *access_decls = nreverse (*access_decls);
3110 /* If TYPE is an empty class type, records its OFFSET in the table of
3114 record_subobject_offset (tree type, tree offset, splay_tree offsets)
3118 if (!is_empty_class (type))
3121 /* Record the location of this empty object in OFFSETS. */
3122 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3124 n = splay_tree_insert (offsets,
3125 (splay_tree_key) offset,
3126 (splay_tree_value) NULL_TREE);
3127 n->value = ((splay_tree_value)
3128 tree_cons (NULL_TREE,
3135 /* Returns nonzero if TYPE is an empty class type and there is
3136 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3139 check_subobject_offset (tree type, tree offset, splay_tree offsets)
3144 if (!is_empty_class (type))
3147 /* Record the location of this empty object in OFFSETS. */
3148 n = splay_tree_lookup (offsets, (splay_tree_key) offset);
3152 for (t = (tree) n->value; t; t = TREE_CHAIN (t))
3153 if (same_type_p (TREE_VALUE (t), type))
3159 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3160 F for every subobject, passing it the type, offset, and table of
3161 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3164 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3165 than MAX_OFFSET will not be walked.
3167 If F returns a nonzero value, the traversal ceases, and that value
3168 is returned. Otherwise, returns zero. */
3171 walk_subobject_offsets (tree type,
3172 subobject_offset_fn f,
3179 tree type_binfo = NULL_TREE;
3181 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3183 if (max_offset && INT_CST_LT (max_offset, offset))
3186 if (type == error_mark_node)
3191 if (abi_version_at_least (2))
3193 type = BINFO_TYPE (type);
3196 if (CLASS_TYPE_P (type))
3202 /* Avoid recursing into objects that are not interesting. */
3203 if (!CLASSTYPE_CONTAINS_EMPTY_CLASS_P (type))
3206 /* Record the location of TYPE. */
3207 r = (*f) (type, offset, offsets);
3211 /* Iterate through the direct base classes of TYPE. */
3213 type_binfo = TYPE_BINFO (type);
3214 for (i = 0; BINFO_BASE_ITERATE (type_binfo, i, binfo); i++)
3218 if (abi_version_at_least (2)
3219 && BINFO_VIRTUAL_P (binfo))
3223 && BINFO_VIRTUAL_P (binfo)
3224 && !BINFO_PRIMARY_P (binfo))
3227 if (!abi_version_at_least (2))
3228 binfo_offset = size_binop (PLUS_EXPR,
3230 BINFO_OFFSET (binfo));
3234 /* We cannot rely on BINFO_OFFSET being set for the base
3235 class yet, but the offsets for direct non-virtual
3236 bases can be calculated by going back to the TYPE. */
3237 orig_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), i);
3238 binfo_offset = size_binop (PLUS_EXPR,
3240 BINFO_OFFSET (orig_binfo));
3243 r = walk_subobject_offsets (binfo,
3248 (abi_version_at_least (2)
3249 ? /*vbases_p=*/0 : vbases_p));
3254 if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
3257 VEC(tree,gc) *vbases;
3259 /* Iterate through the virtual base classes of TYPE. In G++
3260 3.2, we included virtual bases in the direct base class
3261 loop above, which results in incorrect results; the
3262 correct offsets for virtual bases are only known when
3263 working with the most derived type. */
3265 for (vbases = CLASSTYPE_VBASECLASSES (type), ix = 0;
3266 VEC_iterate (tree, vbases, ix, binfo); ix++)
3268 r = walk_subobject_offsets (binfo,
3270 size_binop (PLUS_EXPR,
3272 BINFO_OFFSET (binfo)),
3281 /* We still have to walk the primary base, if it is
3282 virtual. (If it is non-virtual, then it was walked
3284 tree vbase = get_primary_binfo (type_binfo);
3286 if (vbase && BINFO_VIRTUAL_P (vbase)
3287 && BINFO_PRIMARY_P (vbase)
3288 && BINFO_INHERITANCE_CHAIN (vbase) == type_binfo)
3290 r = (walk_subobject_offsets
3292 offsets, max_offset, /*vbases_p=*/0));
3299 /* Iterate through the fields of TYPE. */
3300 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3301 if (TREE_CODE (field) == FIELD_DECL && !DECL_ARTIFICIAL (field))
3305 if (abi_version_at_least (2))
3306 field_offset = byte_position (field);
3308 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3309 field_offset = DECL_FIELD_OFFSET (field);
3311 r = walk_subobject_offsets (TREE_TYPE (field),
3313 size_binop (PLUS_EXPR,
3323 else if (TREE_CODE (type) == ARRAY_TYPE)
3325 tree element_type = strip_array_types (type);
3326 tree domain = TYPE_DOMAIN (type);
3329 /* Avoid recursing into objects that are not interesting. */
3330 if (!CLASS_TYPE_P (element_type)
3331 || !CLASSTYPE_CONTAINS_EMPTY_CLASS_P (element_type))
3334 /* Step through each of the elements in the array. */
3335 for (index = size_zero_node;
3336 /* G++ 3.2 had an off-by-one error here. */
3337 (abi_version_at_least (2)
3338 ? !INT_CST_LT (TYPE_MAX_VALUE (domain), index)
3339 : INT_CST_LT (index, TYPE_MAX_VALUE (domain)));
3340 index = size_binop (PLUS_EXPR, index, size_one_node))
3342 r = walk_subobject_offsets (TREE_TYPE (type),
3350 offset = size_binop (PLUS_EXPR, offset,
3351 TYPE_SIZE_UNIT (TREE_TYPE (type)));
3352 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3353 there's no point in iterating through the remaining
3354 elements of the array. */
3355 if (max_offset && INT_CST_LT (max_offset, offset))
3363 /* Record all of the empty subobjects of TYPE (either a type or a
3364 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3365 is being placed at OFFSET; otherwise, it is a base class that is
3366 being placed at OFFSET. */
3369 record_subobject_offsets (tree type,
3372 bool is_data_member)
3375 /* If recording subobjects for a non-static data member or a
3376 non-empty base class , we do not need to record offsets beyond
3377 the size of the biggest empty class. Additional data members
3378 will go at the end of the class. Additional base classes will go
3379 either at offset zero (if empty, in which case they cannot
3380 overlap with offsets past the size of the biggest empty class) or
3381 at the end of the class.
3383 However, if we are placing an empty base class, then we must record
3384 all offsets, as either the empty class is at offset zero (where
3385 other empty classes might later be placed) or at the end of the
3386 class (where other objects might then be placed, so other empty
3387 subobjects might later overlap). */
3389 || !is_empty_class (BINFO_TYPE (type)))
3390 max_offset = sizeof_biggest_empty_class;
3392 max_offset = NULL_TREE;
3393 walk_subobject_offsets (type, record_subobject_offset, offset,
3394 offsets, max_offset, is_data_member);
3397 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3398 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3399 virtual bases of TYPE are examined. */
3402 layout_conflict_p (tree type,
3407 splay_tree_node max_node;
3409 /* Get the node in OFFSETS that indicates the maximum offset where
3410 an empty subobject is located. */
3411 max_node = splay_tree_max (offsets);
3412 /* If there aren't any empty subobjects, then there's no point in
3413 performing this check. */
3417 return walk_subobject_offsets (type, check_subobject_offset, offset,
3418 offsets, (tree) (max_node->key),
3422 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3423 non-static data member of the type indicated by RLI. BINFO is the
3424 binfo corresponding to the base subobject, OFFSETS maps offsets to
3425 types already located at those offsets. This function determines
3426 the position of the DECL. */
3429 layout_nonempty_base_or_field (record_layout_info rli,
3434 tree offset = NULL_TREE;
3440 /* For the purposes of determining layout conflicts, we want to
3441 use the class type of BINFO; TREE_TYPE (DECL) will be the
3442 CLASSTYPE_AS_BASE version, which does not contain entries for
3443 zero-sized bases. */
3444 type = TREE_TYPE (binfo);
3449 type = TREE_TYPE (decl);
3453 /* Try to place the field. It may take more than one try if we have
3454 a hard time placing the field without putting two objects of the
3455 same type at the same address. */
3458 struct record_layout_info_s old_rli = *rli;
3460 /* Place this field. */
3461 place_field (rli, decl);
3462 offset = byte_position (decl);
3464 /* We have to check to see whether or not there is already
3465 something of the same type at the offset we're about to use.
3466 For example, consider:
3469 struct T : public S { int i; };
3470 struct U : public S, public T {};
3472 Here, we put S at offset zero in U. Then, we can't put T at
3473 offset zero -- its S component would be at the same address
3474 as the S we already allocated. So, we have to skip ahead.
3475 Since all data members, including those whose type is an
3476 empty class, have nonzero size, any overlap can happen only
3477 with a direct or indirect base-class -- it can't happen with
3479 /* In a union, overlap is permitted; all members are placed at
3481 if (TREE_CODE (rli->t) == UNION_TYPE)
3483 /* G++ 3.2 did not check for overlaps when placing a non-empty
3485 if (!abi_version_at_least (2) && binfo && BINFO_VIRTUAL_P (binfo))
3487 if (layout_conflict_p (field_p ? type : binfo, offset,
3490 /* Strip off the size allocated to this field. That puts us
3491 at the first place we could have put the field with
3492 proper alignment. */
3495 /* Bump up by the alignment required for the type. */
3497 = size_binop (PLUS_EXPR, rli->bitpos,
3499 ? CLASSTYPE_ALIGN (type)
3500 : TYPE_ALIGN (type)));
3501 normalize_rli (rli);
3504 /* There was no conflict. We're done laying out this field. */
3508 /* Now that we know where it will be placed, update its
3510 if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo)))
3511 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3512 this point because their BINFO_OFFSET is copied from another
3513 hierarchy. Therefore, we may not need to add the entire
3515 propagate_binfo_offsets (binfo,
3516 size_diffop (convert (ssizetype, offset),
3518 BINFO_OFFSET (binfo))));
3521 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3524 empty_base_at_nonzero_offset_p (tree type,
3526 splay_tree offsets ATTRIBUTE_UNUSED)
3528 return is_empty_class (type) && !integer_zerop (offset);
3531 /* Layout the empty base BINFO. EOC indicates the byte currently just
3532 past the end of the class, and should be correctly aligned for a
3533 class of the type indicated by BINFO; OFFSETS gives the offsets of
3534 the empty bases allocated so far. T is the most derived
3535 type. Return nonzero iff we added it at the end. */
3538 layout_empty_base (record_layout_info rli, tree binfo,
3539 tree eoc, splay_tree offsets)
3542 tree basetype = BINFO_TYPE (binfo);
3545 /* This routine should only be used for empty classes. */
3546 gcc_assert (is_empty_class (basetype));
3547 alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype));
3549 if (!integer_zerop (BINFO_OFFSET (binfo)))
3551 if (abi_version_at_least (2))
3552 propagate_binfo_offsets
3553 (binfo, size_diffop (size_zero_node, BINFO_OFFSET (binfo)));
3556 "offset of empty base %qT may not be ABI-compliant and may"
3557 "change in a future version of GCC",
3558 BINFO_TYPE (binfo));
3561 /* This is an empty base class. We first try to put it at offset
3563 if (layout_conflict_p (binfo,
3564 BINFO_OFFSET (binfo),
3568 /* That didn't work. Now, we move forward from the next
3569 available spot in the class. */
3571 propagate_binfo_offsets (binfo, convert (ssizetype, eoc));
3574 if (!layout_conflict_p (binfo,
3575 BINFO_OFFSET (binfo),
3578 /* We finally found a spot where there's no overlap. */
3581 /* There's overlap here, too. Bump along to the next spot. */
3582 propagate_binfo_offsets (binfo, alignment);
3586 if (CLASSTYPE_USER_ALIGN (basetype))
3588 rli->record_align = MAX (rli->record_align, CLASSTYPE_ALIGN (basetype));
3590 rli->unpacked_align = MAX (rli->unpacked_align, CLASSTYPE_ALIGN (basetype));
3591 TYPE_USER_ALIGN (rli->t) = 1;
3597 /* Layout the base given by BINFO in the class indicated by RLI.
3598 *BASE_ALIGN is a running maximum of the alignments of
3599 any base class. OFFSETS gives the location of empty base
3600 subobjects. T is the most derived type. Return nonzero if the new
3601 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3602 *NEXT_FIELD, unless BINFO is for an empty base class.
3604 Returns the location at which the next field should be inserted. */
3607 build_base_field (record_layout_info rli, tree binfo,
3608 splay_tree offsets, tree *next_field)
3611 tree basetype = BINFO_TYPE (binfo);
3613 if (!COMPLETE_TYPE_P (basetype))
3614 /* This error is now reported in xref_tag, thus giving better
3615 location information. */
3618 /* Place the base class. */
3619 if (!is_empty_class (basetype))
3623 /* The containing class is non-empty because it has a non-empty
3625 CLASSTYPE_EMPTY_P (t) = 0;
3627 /* Create the FIELD_DECL. */
3628 decl = build_decl (FIELD_DECL, NULL_TREE, CLASSTYPE_AS_BASE (basetype));
3629 DECL_ARTIFICIAL (decl) = 1;
3630 DECL_IGNORED_P (decl) = 1;
3631 DECL_FIELD_CONTEXT (decl) = t;
3632 if (CLASSTYPE_AS_BASE (basetype))
3634 DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype);
3635 DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype);
3636 DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype);
3637 DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype);
3638 DECL_MODE (decl) = TYPE_MODE (basetype);
3639 DECL_FIELD_IS_BASE (decl) = 1;
3641 /* Try to place the field. It may take more than one try if we
3642 have a hard time placing the field without putting two
3643 objects of the same type at the same address. */
3644 layout_nonempty_base_or_field (rli, decl, binfo, offsets);
3645 /* Add the new FIELD_DECL to the list of fields for T. */
3646 TREE_CHAIN (decl) = *next_field;
3648 next_field = &TREE_CHAIN (decl);
3656 /* On some platforms (ARM), even empty classes will not be
3658 eoc = round_up (rli_size_unit_so_far (rli),
3659 CLASSTYPE_ALIGN_UNIT (basetype));
3660 atend = layout_empty_base (rli, binfo, eoc, offsets);
3661 /* A nearly-empty class "has no proper base class that is empty,
3662 not morally virtual, and at an offset other than zero." */
3663 if (!BINFO_VIRTUAL_P (binfo) && CLASSTYPE_NEARLY_EMPTY_P (t))
3666 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3667 /* The check above (used in G++ 3.2) is insufficient because
3668 an empty class placed at offset zero might itself have an
3669 empty base at a nonzero offset. */
3670 else if (walk_subobject_offsets (basetype,
3671 empty_base_at_nonzero_offset_p,
3674 /*max_offset=*/NULL_TREE,
3677 if (abi_version_at_least (2))
3678 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
3681 "class %qT will be considered nearly empty in a "
3682 "future version of GCC", t);
3686 /* We do not create a FIELD_DECL for empty base classes because
3687 it might overlap some other field. We want to be able to
3688 create CONSTRUCTORs for the class by iterating over the
3689 FIELD_DECLs, and the back end does not handle overlapping
3692 /* An empty virtual base causes a class to be non-empty
3693 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3694 here because that was already done when the virtual table
3695 pointer was created. */
3698 /* Record the offsets of BINFO and its base subobjects. */
3699 record_subobject_offsets (binfo,
3700 BINFO_OFFSET (binfo),
3702 /*is_data_member=*/false);
3707 /* Layout all of the non-virtual base classes. Record empty
3708 subobjects in OFFSETS. T is the most derived type. Return nonzero
3709 if the type cannot be nearly empty. The fields created
3710 corresponding to the base classes will be inserted at
3714 build_base_fields (record_layout_info rli,
3715 splay_tree offsets, tree *next_field)
3717 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3720 int n_baseclasses = BINFO_N_BASE_BINFOS (TYPE_BINFO (t));
3723 /* The primary base class is always allocated first. */
3724 if (CLASSTYPE_HAS_PRIMARY_BASE_P (t))
3725 next_field = build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (t),
3726 offsets, next_field);
3728 /* Now allocate the rest of the bases. */
3729 for (i = 0; i < n_baseclasses; ++i)
3733 base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (t), i);
3735 /* The primary base was already allocated above, so we don't
3736 need to allocate it again here. */
3737 if (base_binfo == CLASSTYPE_PRIMARY_BINFO (t))
3740 /* Virtual bases are added at the end (a primary virtual base
3741 will have already been added). */
3742 if (BINFO_VIRTUAL_P (base_binfo))
3745 next_field = build_base_field (rli, base_binfo,
3746 offsets, next_field);
3750 /* Go through the TYPE_METHODS of T issuing any appropriate
3751 diagnostics, figuring out which methods override which other
3752 methods, and so forth. */
3755 check_methods (tree t)
3759 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
3761 check_for_override (x, t);
3762 if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x))
3763 error ("initializer specified for non-virtual method %q+D", x);
3764 /* The name of the field is the original field name
3765 Save this in auxiliary field for later overloading. */
3766 if (DECL_VINDEX (x))
3768 TYPE_POLYMORPHIC_P (t) = 1;
3769 if (DECL_PURE_VIRTUAL_P (x))
3770 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
3772 /* All user-provided destructors are non-trivial. */
3773 if (DECL_DESTRUCTOR_P (x) && !DECL_DEFAULTED_FN (x))
3774 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 1;
3778 /* FN is a constructor or destructor. Clone the declaration to create
3779 a specialized in-charge or not-in-charge version, as indicated by
3783 build_clone (tree fn, tree name)
3788 /* Copy the function. */
3789 clone = copy_decl (fn);
3790 /* Remember where this function came from. */
3791 DECL_CLONED_FUNCTION (clone) = fn;
3792 DECL_ABSTRACT_ORIGIN (clone) = fn;
3793 /* Reset the function name. */
3794 DECL_NAME (clone) = name;
3795 SET_DECL_ASSEMBLER_NAME (clone, NULL_TREE);
3796 /* There's no pending inline data for this function. */
3797 DECL_PENDING_INLINE_INFO (clone) = NULL;
3798 DECL_PENDING_INLINE_P (clone) = 0;
3799 /* And it hasn't yet been deferred. */
3800 DECL_DEFERRED_FN (clone) = 0;
3802 /* The base-class destructor is not virtual. */
3803 if (name == base_dtor_identifier)
3805 DECL_VIRTUAL_P (clone) = 0;
3806 if (TREE_CODE (clone) != TEMPLATE_DECL)
3807 DECL_VINDEX (clone) = NULL_TREE;
3810 /* If there was an in-charge parameter, drop it from the function
3812 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3818 exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
3819 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
3820 parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone));
3821 /* Skip the `this' parameter. */
3822 parmtypes = TREE_CHAIN (parmtypes);
3823 /* Skip the in-charge parameter. */
3824 parmtypes = TREE_CHAIN (parmtypes);
3825 /* And the VTT parm, in a complete [cd]tor. */
3826 if (DECL_HAS_VTT_PARM_P (fn)
3827 && ! DECL_NEEDS_VTT_PARM_P (clone))
3828 parmtypes = TREE_CHAIN (parmtypes);
3829 /* If this is subobject constructor or destructor, add the vtt
3832 = build_method_type_directly (basetype,
3833 TREE_TYPE (TREE_TYPE (clone)),
3836 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone),
3839 = cp_build_type_attribute_variant (TREE_TYPE (clone),
3840 TYPE_ATTRIBUTES (TREE_TYPE (fn)));
3843 /* Copy the function parameters. But, DECL_ARGUMENTS on a TEMPLATE_DECL
3844 aren't function parameters; those are the template parameters. */
3845 if (TREE_CODE (clone) != TEMPLATE_DECL)
3847 DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone));
3848 /* Remove the in-charge parameter. */
3849 if (DECL_HAS_IN_CHARGE_PARM_P (clone))
3851 TREE_CHAIN (DECL_ARGUMENTS (clone))
3852 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3853 DECL_HAS_IN_CHARGE_PARM_P (clone) = 0;
3855 /* And the VTT parm, in a complete [cd]tor. */
3856 if (DECL_HAS_VTT_PARM_P (fn))
3858 if (DECL_NEEDS_VTT_PARM_P (clone))
3859 DECL_HAS_VTT_PARM_P (clone) = 1;
3862 TREE_CHAIN (DECL_ARGUMENTS (clone))
3863 = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone)));
3864 DECL_HAS_VTT_PARM_P (clone) = 0;
3868 for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms))
3870 DECL_CONTEXT (parms) = clone;
3871 cxx_dup_lang_specific_decl (parms);
3875 /* Create the RTL for this function. */
3876 SET_DECL_RTL (clone, NULL_RTX);
3877 rest_of_decl_compilation (clone, /*top_level=*/1, at_eof);
3879 /* Make it easy to find the CLONE given the FN. */
3880 TREE_CHAIN (clone) = TREE_CHAIN (fn);
3881 TREE_CHAIN (fn) = clone;
3883 /* If this is a template, handle the DECL_TEMPLATE_RESULT as well. */
3884 if (TREE_CODE (clone) == TEMPLATE_DECL)
3888 DECL_TEMPLATE_RESULT (clone)
3889 = build_clone (DECL_TEMPLATE_RESULT (clone), name);
3890 result = DECL_TEMPLATE_RESULT (clone);
3891 DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result));
3892 DECL_TI_TEMPLATE (result) = clone;
3895 note_decl_for_pch (clone);
3900 /* Produce declarations for all appropriate clones of FN. If
3901 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
3902 CLASTYPE_METHOD_VEC as well. */
3905 clone_function_decl (tree fn, int update_method_vec_p)
3909 /* Avoid inappropriate cloning. */
3911 && DECL_CLONED_FUNCTION (TREE_CHAIN (fn)))
3914 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
3916 /* For each constructor, we need two variants: an in-charge version
3917 and a not-in-charge version. */
3918 clone = build_clone (fn, complete_ctor_identifier);
3919 if (update_method_vec_p)
3920 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3921 clone = build_clone (fn, base_ctor_identifier);
3922 if (update_method_vec_p)
3923 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3927 gcc_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn));
3929 /* For each destructor, we need three variants: an in-charge
3930 version, a not-in-charge version, and an in-charge deleting
3931 version. We clone the deleting version first because that
3932 means it will go second on the TYPE_METHODS list -- and that
3933 corresponds to the correct layout order in the virtual
3936 For a non-virtual destructor, we do not build a deleting
3938 if (DECL_VIRTUAL_P (fn))
3940 clone = build_clone (fn, deleting_dtor_identifier);
3941 if (update_method_vec_p)
3942 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3944 clone = build_clone (fn, complete_dtor_identifier);
3945 if (update_method_vec_p)
3946 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3947 clone = build_clone (fn, base_dtor_identifier);
3948 if (update_method_vec_p)
3949 add_method (DECL_CONTEXT (clone), clone, NULL_TREE);
3952 /* Note that this is an abstract function that is never emitted. */
3953 DECL_ABSTRACT (fn) = 1;
3956 /* DECL is an in charge constructor, which is being defined. This will
3957 have had an in class declaration, from whence clones were
3958 declared. An out-of-class definition can specify additional default
3959 arguments. As it is the clones that are involved in overload
3960 resolution, we must propagate the information from the DECL to its
3964 adjust_clone_args (tree decl)
3968 for (clone = TREE_CHAIN (decl); clone && DECL_CLONED_FUNCTION (clone);
3969 clone = TREE_CHAIN (clone))
3971 tree orig_clone_parms = TYPE_ARG_TYPES (TREE_TYPE (clone));
3972 tree orig_decl_parms = TYPE_ARG_TYPES (TREE_TYPE (decl));
3973 tree decl_parms, clone_parms;
3975 clone_parms = orig_clone_parms;
3977 /* Skip the 'this' parameter. */
3978 orig_clone_parms = TREE_CHAIN (orig_clone_parms);
3979 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3981 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
3982 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3983 if (DECL_HAS_VTT_PARM_P (decl))
3984 orig_decl_parms = TREE_CHAIN (orig_decl_parms);
3986 clone_parms = orig_clone_parms;
3987 if (DECL_HAS_VTT_PARM_P (clone))
3988 clone_parms = TREE_CHAIN (clone_parms);
3990 for (decl_parms = orig_decl_parms; decl_parms;
3991 decl_parms = TREE_CHAIN (decl_parms),
3992 clone_parms = TREE_CHAIN (clone_parms))
3994 gcc_assert (same_type_p (TREE_TYPE (decl_parms),
3995 TREE_TYPE (clone_parms)));
3997 if (TREE_PURPOSE (decl_parms) && !TREE_PURPOSE (clone_parms))
3999 /* A default parameter has been added. Adjust the
4000 clone's parameters. */
4001 tree exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone));
4002 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone));
4005 clone_parms = orig_decl_parms;
4007 if (DECL_HAS_VTT_PARM_P (clone))
4009 clone_parms = tree_cons (TREE_PURPOSE (orig_clone_parms),
4010 TREE_VALUE (orig_clone_parms),
4012 TREE_TYPE (clone_parms) = TREE_TYPE (orig_clone_parms);
4014 type = build_method_type_directly (basetype,
4015 TREE_TYPE (TREE_TYPE (clone)),
4018 type = build_exception_variant (type, exceptions);
4019 TREE_TYPE (clone) = type;
4021 clone_parms = NULL_TREE;
4025 gcc_assert (!clone_parms);
4029 /* For each of the constructors and destructors in T, create an
4030 in-charge and not-in-charge variant. */
4033 clone_constructors_and_destructors (tree t)
4037 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4039 if (!CLASSTYPE_METHOD_VEC (t))
4042 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4043 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4044 for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4045 clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1);
4048 /* Returns true iff class T has a user-defined constructor other than
4049 the default constructor. */
4052 type_has_user_nondefault_constructor (tree t)
4056 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4059 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4061 tree fn = OVL_CURRENT (fns);
4062 if (!DECL_ARTIFICIAL (fn)
4063 && (TREE_CODE (fn) == TEMPLATE_DECL
4064 || (skip_artificial_parms_for (fn, DECL_ARGUMENTS (fn))
4072 /* Returns true iff FN is a user-provided function, i.e. user-declared
4073 and not defaulted at its first declaration. */
4076 user_provided_p (tree fn)
4078 if (TREE_CODE (fn) == TEMPLATE_DECL)
4081 return (!DECL_ARTIFICIAL (fn)
4082 && !(DECL_DEFAULTED_FN (fn)
4083 && DECL_INITIALIZED_IN_CLASS_P (fn)));
4086 /* Returns true iff class T has a user-provided constructor. */
4089 type_has_user_provided_constructor (tree t)
4093 if (!CLASS_TYPE_P (t))
4096 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4099 /* This can happen in error cases; avoid crashing. */
4100 if (!CLASSTYPE_METHOD_VEC (t))
4103 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4104 if (user_provided_p (OVL_CURRENT (fns)))
4110 /* Returns true iff class T has a user-provided default constructor. */
4113 type_has_user_provided_default_constructor (tree t)
4117 if (!TYPE_HAS_USER_CONSTRUCTOR (t))
4120 for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns))
4122 tree fn = OVL_CURRENT (fns);
4123 if (TREE_CODE (fn) == FUNCTION_DECL
4124 && user_provided_p (fn))
4126 args = FUNCTION_FIRST_USER_PARMTYPE (fn);
4127 while (args && TREE_PURPOSE (args))
4128 args = TREE_CHAIN (args);
4129 if (!args || args == void_list_node)
4137 /* Returns true if FN can be explicitly defaulted. */
4140 defaultable_fn_p (tree fn)
4142 if (DECL_CONSTRUCTOR_P (fn))
4144 if (FUNCTION_FIRST_USER_PARMTYPE (fn) == void_list_node)
4146 else if (copy_fn_p (fn) > 0
4147 && (TREE_CHAIN (FUNCTION_FIRST_USER_PARMTYPE (fn))
4153 else if (DECL_DESTRUCTOR_P (fn))
4155 else if (DECL_ASSIGNMENT_OPERATOR_P (fn)
4156 && DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR)
4157 return copy_fn_p (fn);
4162 /* Remove all zero-width bit-fields from T. */
4165 remove_zero_width_bit_fields (tree t)
4169 fieldsp = &TYPE_FIELDS (t);
4172 if (TREE_CODE (*fieldsp) == FIELD_DECL
4173 && DECL_C_BIT_FIELD (*fieldsp)
4174 && DECL_INITIAL (*fieldsp))
4175 *fieldsp = TREE_CHAIN (*fieldsp);
4177 fieldsp = &TREE_CHAIN (*fieldsp);
4181 /* Returns TRUE iff we need a cookie when dynamically allocating an
4182 array whose elements have the indicated class TYPE. */
4185 type_requires_array_cookie (tree type)
4188 bool has_two_argument_delete_p = false;
4190 gcc_assert (CLASS_TYPE_P (type));
4192 /* If there's a non-trivial destructor, we need a cookie. In order
4193 to iterate through the array calling the destructor for each
4194 element, we'll have to know how many elements there are. */
4195 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4198 /* If the usual deallocation function is a two-argument whose second
4199 argument is of type `size_t', then we have to pass the size of
4200 the array to the deallocation function, so we will need to store
4202 fns = lookup_fnfields (TYPE_BINFO (type),
4203 ansi_opname (VEC_DELETE_EXPR),
4205 /* If there are no `operator []' members, or the lookup is
4206 ambiguous, then we don't need a cookie. */
4207 if (!fns || fns == error_mark_node)
4209 /* Loop through all of the functions. */
4210 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
4215 /* Select the current function. */
4216 fn = OVL_CURRENT (fns);
4217 /* See if this function is a one-argument delete function. If
4218 it is, then it will be the usual deallocation function. */
4219 second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn)));
4220 if (second_parm == void_list_node)
4222 /* Do not consider this function if its second argument is an
4226 /* Otherwise, if we have a two-argument function and the second
4227 argument is `size_t', it will be the usual deallocation
4228 function -- unless there is one-argument function, too. */
4229 if (TREE_CHAIN (second_parm) == void_list_node
4230 && same_type_p (TREE_VALUE (second_parm), size_type_node))
4231 has_two_argument_delete_p = true;
4234 return has_two_argument_delete_p;
4237 /* Check the validity of the bases and members declared in T. Add any
4238 implicitly-generated functions (like copy-constructors and
4239 assignment operators). Compute various flag bits (like
4240 CLASSTYPE_NON_POD_T) for T. This routine works purely at the C++
4241 level: i.e., independently of the ABI in use. */
4244 check_bases_and_members (tree t)
4246 /* Nonzero if the implicitly generated copy constructor should take
4247 a non-const reference argument. */
4248 int cant_have_const_ctor;
4249 /* Nonzero if the implicitly generated assignment operator
4250 should take a non-const reference argument. */
4251 int no_const_asn_ref;
4253 bool saved_complex_asn_ref;
4254 bool saved_nontrivial_dtor;
4256 /* By default, we use const reference arguments and generate default
4258 cant_have_const_ctor = 0;
4259 no_const_asn_ref = 0;
4261 /* Check all the base-classes. */
4262 check_bases (t, &cant_have_const_ctor,
4265 /* Check all the method declarations. */
4268 /* Save the initial values of these flags which only indicate whether
4269 or not the class has user-provided functions. As we analyze the
4270 bases and members we can set these flags for other reasons. */
4271 saved_complex_asn_ref = TYPE_HAS_COMPLEX_ASSIGN_REF (t);
4272 saved_nontrivial_dtor = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t);
4274 /* Check all the data member declarations. We cannot call
4275 check_field_decls until we have called check_bases check_methods,
4276 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4277 being set appropriately. */
4278 check_field_decls (t, &access_decls,
4279 &cant_have_const_ctor,
4282 /* A nearly-empty class has to be vptr-containing; a nearly empty
4283 class contains just a vptr. */
4284 if (!TYPE_CONTAINS_VPTR_P (t))
4285 CLASSTYPE_NEARLY_EMPTY_P (t) = 0;
4287 /* Do some bookkeeping that will guide the generation of implicitly
4288 declared member functions. */
4289 TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4290 /* We need to call a constructor for this class if it has a
4291 user-provided constructor, or if the default constructor is going
4292 to initialize the vptr. (This is not an if-and-only-if;
4293 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4294 themselves need constructing.) */
4295 TYPE_NEEDS_CONSTRUCTING (t)
4296 |= (type_has_user_provided_constructor (t) || TYPE_CONTAINS_VPTR_P (t));
4299 An aggregate is an array or a class with no user-provided
4300 constructors ... and no virtual functions.
4302 Again, other conditions for being an aggregate are checked
4304 CLASSTYPE_NON_AGGREGATE (t)
4305 |= (type_has_user_provided_constructor (t) || TYPE_POLYMORPHIC_P (t));
4306 CLASSTYPE_NON_POD_P (t)
4307 |= (CLASSTYPE_NON_AGGREGATE (t)
4308 || saved_nontrivial_dtor || saved_complex_asn_ref);
4309 TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_CONTAINS_VPTR_P (t);
4310 TYPE_HAS_COMPLEX_DFLT (t) |= TYPE_CONTAINS_VPTR_P (t);
4312 /* If the class has no user-declared constructor, but does have
4313 non-static const or reference data members that can never be
4314 initialized, issue a warning. */
4315 if (warn_uninitialized
4316 /* Classes with user-declared constructors are presumed to
4317 initialize these members. */
4318 && !TYPE_HAS_USER_CONSTRUCTOR (t)
4319 /* Aggregates can be initialized with brace-enclosed
4321 && CLASSTYPE_NON_AGGREGATE (t))
4325 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
4329 if (TREE_CODE (field) != FIELD_DECL)
4332 type = TREE_TYPE (field);
4333 if (TREE_CODE (type) == REFERENCE_TYPE)
4334 warning (OPT_Wuninitialized, "non-static reference %q+#D "
4335 "in class without a constructor", field);
4336 else if (CP_TYPE_CONST_P (type)
4337 && (!CLASS_TYPE_P (type)
4338 || !TYPE_HAS_DEFAULT_CONSTRUCTOR (type)))
4339 warning (OPT_Wuninitialized, "non-static const member %q+#D "
4340 "in class without a constructor", field);
4344 /* Synthesize any needed methods. */
4345 add_implicitly_declared_members (t,
4346 cant_have_const_ctor,
4349 /* Create the in-charge and not-in-charge variants of constructors
4351 clone_constructors_and_destructors (t);
4353 /* Process the using-declarations. */
4354 for (; access_decls; access_decls = TREE_CHAIN (access_decls))
4355 handle_using_decl (TREE_VALUE (access_decls), t);
4357 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4358 finish_struct_methods (t);
4360 /* Figure out whether or not we will need a cookie when dynamically
4361 allocating an array of this type. */
4362 TYPE_LANG_SPECIFIC (t)->u.c.vec_new_uses_cookie
4363 = type_requires_array_cookie (t);
4366 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4367 accordingly. If a new vfield was created (because T doesn't have a
4368 primary base class), then the newly created field is returned. It
4369 is not added to the TYPE_FIELDS list; it is the caller's
4370 responsibility to do that. Accumulate declared virtual functions
4374 create_vtable_ptr (tree t, tree* virtuals_p)
4378 /* Collect the virtual functions declared in T. */
4379 for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn))
4380 if (DECL_VINDEX (fn) && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn)
4381 && TREE_CODE (DECL_VINDEX (fn)) != INTEGER_CST)
4383 tree new_virtual = make_node (TREE_LIST);
4385 BV_FN (new_virtual) = fn;
4386 BV_DELTA (new_virtual) = integer_zero_node;
4387 BV_VCALL_INDEX (new_virtual) = NULL_TREE;
4389 TREE_CHAIN (new_virtual) = *virtuals_p;
4390 *virtuals_p = new_virtual;
4393 /* If we couldn't find an appropriate base class, create a new field
4394 here. Even if there weren't any new virtual functions, we might need a
4395 new virtual function table if we're supposed to include vptrs in
4396 all classes that need them. */
4397 if (!TYPE_VFIELD (t) && (*virtuals_p || TYPE_CONTAINS_VPTR_P (t)))
4399 /* We build this decl with vtbl_ptr_type_node, which is a
4400 `vtable_entry_type*'. It might seem more precise to use
4401 `vtable_entry_type (*)[N]' where N is the number of virtual
4402 functions. However, that would require the vtable pointer in
4403 base classes to have a different type than the vtable pointer
4404 in derived classes. We could make that happen, but that
4405 still wouldn't solve all the problems. In particular, the
4406 type-based alias analysis code would decide that assignments
4407 to the base class vtable pointer can't alias assignments to
4408 the derived class vtable pointer, since they have different
4409 types. Thus, in a derived class destructor, where the base
4410 class constructor was inlined, we could generate bad code for
4411 setting up the vtable pointer.
4413 Therefore, we use one type for all vtable pointers. We still
4414 use a type-correct type; it's just doesn't indicate the array
4415 bounds. That's better than using `void*' or some such; it's
4416 cleaner, and it let's the alias analysis code know that these
4417 stores cannot alias stores to void*! */
4420 field = build_decl (FIELD_DECL, get_vfield_name (t), vtbl_ptr_type_node);
4421 DECL_VIRTUAL_P (field) = 1;
4422 DECL_ARTIFICIAL (field) = 1;
4423 DECL_FIELD_CONTEXT (field) = t;
4424 DECL_FCONTEXT (field) = t;
4426 TYPE_VFIELD (t) = field;
4428 /* This class is non-empty. */
4429 CLASSTYPE_EMPTY_P (t) = 0;
4437 /* Fixup the inline function given by INFO now that the class is
4441 fixup_pending_inline (tree fn)
4443 if (DECL_PENDING_INLINE_INFO (fn))
4445 tree args = DECL_ARGUMENTS (fn);
4448 DECL_CONTEXT (args) = fn;
4449 args = TREE_CHAIN (args);
4454 /* Fixup the inline methods and friends in TYPE now that TYPE is
4458 fixup_inline_methods (tree type)
4460 tree method = TYPE_METHODS (type);
4461 VEC(tree,gc) *friends;
4464 if (method && TREE_CODE (method) == TREE_VEC)
4466 if (TREE_VEC_ELT (method, 1))
4467 method = TREE_VEC_ELT (method, 1);
4468 else if (TREE_VEC_ELT (method, 0))
4469 method = TREE_VEC_ELT (method, 0);
4471 method = TREE_VEC_ELT (method, 2);
4474 /* Do inline member functions. */
4475 for (; method; method = TREE_CHAIN (method))
4476 fixup_pending_inline (method);
4479 for (friends = CLASSTYPE_INLINE_FRIENDS (type), ix = 0;
4480 VEC_iterate (tree, friends, ix, method); ix++)
4481 fixup_pending_inline (method);
4482 CLASSTYPE_INLINE_FRIENDS (type) = NULL;
4485 /* Add OFFSET to all base types of BINFO which is a base in the
4486 hierarchy dominated by T.
4488 OFFSET, which is a type offset, is number of bytes. */
4491 propagate_binfo_offsets (tree binfo, tree offset)
4497 /* Update BINFO's offset. */
4498 BINFO_OFFSET (binfo)
4499 = convert (sizetype,
4500 size_binop (PLUS_EXPR,
4501 convert (ssizetype, BINFO_OFFSET (binfo)),
4504 /* Find the primary base class. */
4505 primary_binfo = get_primary_binfo (binfo);
4507 if (primary_binfo && BINFO_INHERITANCE_CHAIN (primary_binfo) == binfo)
4508 propagate_binfo_offsets (primary_binfo, offset);
4510 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4512 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4514 /* Don't do the primary base twice. */
4515 if (base_binfo == primary_binfo)
4518 if (BINFO_VIRTUAL_P (base_binfo))
4521 propagate_binfo_offsets (base_binfo, offset);
4525 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4526 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4527 empty subobjects of T. */
4530 layout_virtual_bases (record_layout_info rli, splay_tree offsets)
4534 bool first_vbase = true;
4537 if (BINFO_N_BASE_BINFOS (TYPE_BINFO (t)) == 0)
4540 if (!abi_version_at_least(2))
4542 /* In G++ 3.2, we incorrectly rounded the size before laying out
4543 the virtual bases. */
4544 finish_record_layout (rli, /*free_p=*/false);
4545 #ifdef STRUCTURE_SIZE_BOUNDARY
4546 /* Packed structures don't need to have minimum size. */
4547 if (! TYPE_PACKED (t))
4548 TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), (unsigned) STRUCTURE_SIZE_BOUNDARY);
4550 rli->offset = TYPE_SIZE_UNIT (t);
4551 rli->bitpos = bitsize_zero_node;
4552 rli->record_align = TYPE_ALIGN (t);
4555 /* Find the last field. The artificial fields created for virtual
4556 bases will go after the last extant field to date. */
4557 next_field = &TYPE_FIELDS (t);
4559 next_field = &TREE_CHAIN (*next_field);
4561 /* Go through the virtual bases, allocating space for each virtual
4562 base that is not already a primary base class. These are
4563 allocated in inheritance graph order. */
4564 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
4566 if (!BINFO_VIRTUAL_P (vbase))
4569 if (!BINFO_PRIMARY_P (vbase))
4571 tree basetype = TREE_TYPE (vbase);
4573 /* This virtual base is not a primary base of any class in the
4574 hierarchy, so we have to add space for it. */
4575 next_field = build_base_field (rli, vbase,
4576 offsets, next_field);
4578 /* If the first virtual base might have been placed at a
4579 lower address, had we started from CLASSTYPE_SIZE, rather
4580 than TYPE_SIZE, issue a warning. There can be both false
4581 positives and false negatives from this warning in rare
4582 cases; to deal with all the possibilities would probably
4583 require performing both layout algorithms and comparing
4584 the results which is not particularly tractable. */
4588 (size_binop (CEIL_DIV_EXPR,
4589 round_up (CLASSTYPE_SIZE (t),
4590 CLASSTYPE_ALIGN (basetype)),
4592 BINFO_OFFSET (vbase))))
4594 "offset of virtual base %qT is not ABI-compliant and "
4595 "may change in a future version of GCC",
4598 first_vbase = false;
4603 /* Returns the offset of the byte just past the end of the base class
4607 end_of_base (tree binfo)
4611 if (!CLASSTYPE_AS_BASE (BINFO_TYPE (binfo)))
4612 size = TYPE_SIZE_UNIT (char_type_node);
4613 else if (is_empty_class (BINFO_TYPE (binfo)))
4614 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4615 allocate some space for it. It cannot have virtual bases, so
4616 TYPE_SIZE_UNIT is fine. */
4617 size = TYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4619 size = CLASSTYPE_SIZE_UNIT (BINFO_TYPE (binfo));
4621 return size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), size);
4624 /* Returns the offset of the byte just past the end of the base class
4625 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4626 only non-virtual bases are included. */
4629 end_of_class (tree t, int include_virtuals_p)
4631 tree result = size_zero_node;
4632 VEC(tree,gc) *vbases;
4638 for (binfo = TYPE_BINFO (t), i = 0;
4639 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4641 if (!include_virtuals_p
4642 && BINFO_VIRTUAL_P (base_binfo)
4643 && (!BINFO_PRIMARY_P (base_binfo)
4644 || BINFO_INHERITANCE_CHAIN (base_binfo) != TYPE_BINFO (t)))
4647 offset = end_of_base (base_binfo);
4648 if (INT_CST_LT_UNSIGNED (result, offset))
4652 /* G++ 3.2 did not check indirect virtual bases. */
4653 if (abi_version_at_least (2) && include_virtuals_p)
4654 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4655 VEC_iterate (tree, vbases, i, base_binfo); i++)
4657 offset = end_of_base (base_binfo);
4658 if (INT_CST_LT_UNSIGNED (result, offset))
4665 /* Warn about bases of T that are inaccessible because they are
4666 ambiguous. For example:
4669 struct T : public S {};
4670 struct U : public S, public T {};
4672 Here, `(S*) new U' is not allowed because there are two `S'
4676 warn_about_ambiguous_bases (tree t)
4679 VEC(tree,gc) *vbases;
4684 /* If there are no repeated bases, nothing can be ambiguous. */
4685 if (!CLASSTYPE_REPEATED_BASE_P (t))
4688 /* Check direct bases. */
4689 for (binfo = TYPE_BINFO (t), i = 0;
4690 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
4692 basetype = BINFO_TYPE (base_binfo);
4694 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4695 warning (0, "direct base %qT inaccessible in %qT due to ambiguity",
4699 /* Check for ambiguous virtual bases. */
4701 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
4702 VEC_iterate (tree, vbases, i, binfo); i++)
4704 basetype = BINFO_TYPE (binfo);
4706 if (!lookup_base (t, basetype, ba_unique | ba_quiet, NULL))
4707 warning (OPT_Wextra, "virtual base %qT inaccessible in %qT due to ambiguity",
4712 /* Compare two INTEGER_CSTs K1 and K2. */
4715 splay_tree_compare_integer_csts (splay_tree_key k1, splay_tree_key k2)
4717 return tree_int_cst_compare ((tree) k1, (tree) k2);
4720 /* Increase the size indicated in RLI to account for empty classes
4721 that are "off the end" of the class. */
4724 include_empty_classes (record_layout_info rli)
4729 /* It might be the case that we grew the class to allocate a
4730 zero-sized base class. That won't be reflected in RLI, yet,
4731 because we are willing to overlay multiple bases at the same
4732 offset. However, now we need to make sure that RLI is big enough
4733 to reflect the entire class. */
4734 eoc = end_of_class (rli->t,
4735 CLASSTYPE_AS_BASE (rli->t) != NULL_TREE);
4736 rli_size = rli_size_unit_so_far (rli);
4737 if (TREE_CODE (rli_size) == INTEGER_CST
4738 && INT_CST_LT_UNSIGNED (rli_size, eoc))
4740 if (!abi_version_at_least (2))
4741 /* In version 1 of the ABI, the size of a class that ends with
4742 a bitfield was not rounded up to a whole multiple of a
4743 byte. Because rli_size_unit_so_far returns only the number
4744 of fully allocated bytes, any extra bits were not included
4746 rli->bitpos = round_down (rli->bitpos, BITS_PER_UNIT);
4748 /* The size should have been rounded to a whole byte. */
4749 gcc_assert (tree_int_cst_equal
4750 (rli->bitpos, round_down (rli->bitpos, BITS_PER_UNIT)));
4752 = size_binop (PLUS_EXPR,
4754 size_binop (MULT_EXPR,
4755 convert (bitsizetype,
4756 size_binop (MINUS_EXPR,
4758 bitsize_int (BITS_PER_UNIT)));
4759 normalize_rli (rli);
4763 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4764 BINFO_OFFSETs for all of the base-classes. Position the vtable
4765 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4768 layout_class_type (tree t, tree *virtuals_p)
4770 tree non_static_data_members;
4773 record_layout_info rli;
4774 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4775 types that appear at that offset. */
4776 splay_tree empty_base_offsets;
4777 /* True if the last field layed out was a bit-field. */
4778 bool last_field_was_bitfield = false;
4779 /* The location at which the next field should be inserted. */
4781 /* T, as a base class. */
4784 /* Keep track of the first non-static data member. */
4785 non_static_data_members = TYPE_FIELDS (t);
4787 /* Start laying out the record. */
4788 rli = start_record_layout (t);
4790 /* Mark all the primary bases in the hierarchy. */
4791 determine_primary_bases (t);
4793 /* Create a pointer to our virtual function table. */
4794 vptr = create_vtable_ptr (t, virtuals_p);
4796 /* The vptr is always the first thing in the class. */
4799 TREE_CHAIN (vptr) = TYPE_FIELDS (t);
4800 TYPE_FIELDS (t) = vptr;
4801 next_field = &TREE_CHAIN (vptr);
4802 place_field (rli, vptr);
4805 next_field = &TYPE_FIELDS (t);
4807 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4808 empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts,
4810 build_base_fields (rli, empty_base_offsets, next_field);
4812 /* Layout the non-static data members. */
4813 for (field = non_static_data_members; field; field = TREE_CHAIN (field))
4818 /* We still pass things that aren't non-static data members to
4819 the back end, in case it wants to do something with them. */
4820 if (TREE_CODE (field) != FIELD_DECL)
4822 place_field (rli, field);
4823 /* If the static data member has incomplete type, keep track
4824 of it so that it can be completed later. (The handling
4825 of pending statics in finish_record_layout is
4826 insufficient; consider:
4829 struct S2 { static S1 s1; };
4831 At this point, finish_record_layout will be called, but
4832 S1 is still incomplete.) */
4833 if (TREE_CODE (field) == VAR_DECL)
4835 maybe_register_incomplete_var (field);
4836 /* The visibility of static data members is determined
4837 at their point of declaration, not their point of
4839 determine_visibility (field);
4844 type = TREE_TYPE (field);
4845 if (type == error_mark_node)
4848 padding = NULL_TREE;
4850 /* If this field is a bit-field whose width is greater than its
4851 type, then there are some special rules for allocating
4853 if (DECL_C_BIT_FIELD (field)
4854 && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field)))
4856 integer_type_kind itk;
4858 bool was_unnamed_p = false;
4859 /* We must allocate the bits as if suitably aligned for the
4860 longest integer type that fits in this many bits. type
4861 of the field. Then, we are supposed to use the left over
4862 bits as additional padding. */
4863 for (itk = itk_char; itk != itk_none; ++itk)
4864 if (INT_CST_LT (DECL_SIZE (field),
4865 TYPE_SIZE (integer_types[itk])))
4868 /* ITK now indicates a type that is too large for the
4869 field. We have to back up by one to find the largest
4871 integer_type = integer_types[itk - 1];
4873 /* Figure out how much additional padding is required. GCC
4874 3.2 always created a padding field, even if it had zero
4876 if (!abi_version_at_least (2)
4877 || INT_CST_LT (TYPE_SIZE (integer_type), DECL_SIZE (field)))
4879 if (abi_version_at_least (2) && TREE_CODE (t) == UNION_TYPE)
4880 /* In a union, the padding field must have the full width
4881 of the bit-field; all fields start at offset zero. */
4882 padding = DECL_SIZE (field);
4885 if (TREE_CODE (t) == UNION_TYPE)
4886 warning (OPT_Wabi, "size assigned to %qT may not be "
4887 "ABI-compliant and may change in a future "
4890 padding = size_binop (MINUS_EXPR, DECL_SIZE (field),
4891 TYPE_SIZE (integer_type));
4894 #ifdef PCC_BITFIELD_TYPE_MATTERS
4895 /* An unnamed bitfield does not normally affect the
4896 alignment of the containing class on a target where
4897 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
4898 make any exceptions for unnamed bitfields when the
4899 bitfields are longer than their types. Therefore, we
4900 temporarily give the field a name. */
4901 if (PCC_BITFIELD_TYPE_MATTERS && !DECL_NAME (field))
4903 was_unnamed_p = true;
4904 DECL_NAME (field) = make_anon_name ();
4907 DECL_SIZE (field) = TYPE_SIZE (integer_type);
4908 DECL_ALIGN (field) = TYPE_ALIGN (integer_type);
4909 DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type);
4910 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4911 empty_base_offsets);
4913 DECL_NAME (field) = NULL_TREE;
4914 /* Now that layout has been performed, set the size of the
4915 field to the size of its declared type; the rest of the
4916 field is effectively invisible. */
4917 DECL_SIZE (field) = TYPE_SIZE (type);
4918 /* We must also reset the DECL_MODE of the field. */
4919 if (abi_version_at_least (2))
4920 DECL_MODE (field) = TYPE_MODE (type);
4922 && DECL_MODE (field) != TYPE_MODE (type))
4923 /* Versions of G++ before G++ 3.4 did not reset the
4926 "the offset of %qD may not be ABI-compliant and may "
4927 "change in a future version of GCC", field);
4930 layout_nonempty_base_or_field (rli, field, NULL_TREE,
4931 empty_base_offsets);
4933 /* Remember the location of any empty classes in FIELD. */
4934 if (abi_version_at_least (2))
4935 record_subobject_offsets (TREE_TYPE (field),
4936 byte_position(field),
4938 /*is_data_member=*/true);
4940 /* If a bit-field does not immediately follow another bit-field,
4941 and yet it starts in the middle of a byte, we have failed to
4942 comply with the ABI. */
4944 && DECL_C_BIT_FIELD (field)
4945 /* The TREE_NO_WARNING flag gets set by Objective-C when
4946 laying out an Objective-C class. The ObjC ABI differs
4947 from the C++ ABI, and so we do not want a warning
4949 && !TREE_NO_WARNING (field)
4950 && !last_field_was_bitfield
4951 && !integer_zerop (size_binop (TRUNC_MOD_EXPR,
4952 DECL_FIELD_BIT_OFFSET (field),
4953 bitsize_unit_node)))
4954 warning (OPT_Wabi, "offset of %q+D is not ABI-compliant and may "
4955 "change in a future version of GCC", field);
4957 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
4958 offset of the field. */
4960 && !tree_int_cst_equal (DECL_FIELD_OFFSET (field),
4961 byte_position (field))
4962 && contains_empty_class_p (TREE_TYPE (field)))
4963 warning (OPT_Wabi, "%q+D contains empty classes which may cause base "
4964 "classes to be placed at different locations in a "
4965 "future version of GCC", field);
4967 /* The middle end uses the type of expressions to determine the
4968 possible range of expression values. In order to optimize
4969 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
4970 must be made aware of the width of "i", via its type.
4972 Because C++ does not have integer types of arbitrary width,
4973 we must (for the purposes of the front end) convert from the
4974 type assigned here to the declared type of the bitfield
4975 whenever a bitfield expression is used as an rvalue.
4976 Similarly, when assigning a value to a bitfield, the value
4977 must be converted to the type given the bitfield here. */
4978 if (DECL_C_BIT_FIELD (field))
4980 unsigned HOST_WIDE_INT width;
4981 tree ftype = TREE_TYPE (field);
4982 width = tree_low_cst (DECL_SIZE (field), /*unsignedp=*/1);
4983 if (width != TYPE_PRECISION (ftype))
4986 = c_build_bitfield_integer_type (width,
4987 TYPE_UNSIGNED (ftype));
4989 = cp_build_qualified_type (TREE_TYPE (field),
4990 TYPE_QUALS (ftype));
4994 /* If we needed additional padding after this field, add it
5000 padding_field = build_decl (FIELD_DECL,
5003 DECL_BIT_FIELD (padding_field) = 1;
5004 DECL_SIZE (padding_field) = padding;
5005 DECL_CONTEXT (padding_field) = t;
5006 DECL_ARTIFICIAL (padding_field) = 1;
5007 DECL_IGNORED_P (padding_field) = 1;
5008 layout_nonempty_base_or_field (rli, padding_field,
5010 empty_base_offsets);
5013 last_field_was_bitfield = DECL_C_BIT_FIELD (field);
5016 if (abi_version_at_least (2) && !integer_zerop (rli->bitpos))
5018 /* Make sure that we are on a byte boundary so that the size of
5019 the class without virtual bases will always be a round number
5021 rli->bitpos = round_up (rli->bitpos, BITS_PER_UNIT);
5022 normalize_rli (rli);
5025 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5027 if (!abi_version_at_least (2))
5028 include_empty_classes(rli);
5030 /* Delete all zero-width bit-fields from the list of fields. Now
5031 that the type is laid out they are no longer important. */
5032 remove_zero_width_bit_fields (t);
5034 /* Create the version of T used for virtual bases. We do not use
5035 make_class_type for this version; this is an artificial type. For
5036 a POD type, we just reuse T. */
5037 if (CLASSTYPE_NON_POD_P (t) || CLASSTYPE_EMPTY_P (t))
5039 base_t = make_node (TREE_CODE (t));
5041 /* Set the size and alignment for the new type. In G++ 3.2, all
5042 empty classes were considered to have size zero when used as
5044 if (!abi_version_at_least (2) && CLASSTYPE_EMPTY_P (t))
5046 TYPE_SIZE (base_t) = bitsize_zero_node;
5047 TYPE_SIZE_UNIT (base_t) = size_zero_node;
5048 if (warn_abi && !integer_zerop (rli_size_unit_so_far (rli)))
5050 "layout of classes derived from empty class %qT "
5051 "may change in a future version of GCC",
5058 /* If the ABI version is not at least two, and the last
5059 field was a bit-field, RLI may not be on a byte
5060 boundary. In particular, rli_size_unit_so_far might
5061 indicate the last complete byte, while rli_size_so_far
5062 indicates the total number of bits used. Therefore,
5063 rli_size_so_far, rather than rli_size_unit_so_far, is
5064 used to compute TYPE_SIZE_UNIT. */
5065 eoc = end_of_class (t, /*include_virtuals_p=*/0);
5066 TYPE_SIZE_UNIT (base_t)
5067 = size_binop (MAX_EXPR,
5069 size_binop (CEIL_DIV_EXPR,
5070 rli_size_so_far (rli),
5071 bitsize_int (BITS_PER_UNIT))),
5074 = size_binop (MAX_EXPR,
5075 rli_size_so_far (rli),
5076 size_binop (MULT_EXPR,
5077 convert (bitsizetype, eoc),
5078 bitsize_int (BITS_PER_UNIT)));
5080 TYPE_ALIGN (base_t) = rli->record_align;
5081 TYPE_USER_ALIGN (base_t) = TYPE_USER_ALIGN (t);
5083 /* Copy the fields from T. */
5084 next_field = &TYPE_FIELDS (base_t);
5085 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5086 if (TREE_CODE (field) == FIELD_DECL)
5088 *next_field = build_decl (FIELD_DECL,
5091 DECL_CONTEXT (*next_field) = base_t;
5092 DECL_FIELD_OFFSET (*next_field) = DECL_FIELD_OFFSET (field);
5093 DECL_FIELD_BIT_OFFSET (*next_field)
5094 = DECL_FIELD_BIT_OFFSET (field);
5095 DECL_SIZE (*next_field) = DECL_SIZE (field);
5096 DECL_MODE (*next_field) = DECL_MODE (field);
5097 next_field = &TREE_CHAIN (*next_field);
5100 /* Record the base version of the type. */
5101 CLASSTYPE_AS_BASE (t) = base_t;
5102 TYPE_CONTEXT (base_t) = t;
5105 CLASSTYPE_AS_BASE (t) = t;
5107 /* Every empty class contains an empty class. */
5108 if (CLASSTYPE_EMPTY_P (t))
5109 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 1;
5111 /* Set the TYPE_DECL for this type to contain the right
5112 value for DECL_OFFSET, so that we can use it as part
5113 of a COMPONENT_REF for multiple inheritance. */
5114 layout_decl (TYPE_MAIN_DECL (t), 0);
5116 /* Now fix up any virtual base class types that we left lying
5117 around. We must get these done before we try to lay out the
5118 virtual function table. As a side-effect, this will remove the
5119 base subobject fields. */
5120 layout_virtual_bases (rli, empty_base_offsets);
5122 /* Make sure that empty classes are reflected in RLI at this
5124 include_empty_classes(rli);
5126 /* Make sure not to create any structures with zero size. */
5127 if (integer_zerop (rli_size_unit_so_far (rli)) && CLASSTYPE_EMPTY_P (t))
5129 build_decl (FIELD_DECL, NULL_TREE, char_type_node));
5131 /* Let the back end lay out the type. */
5132 finish_record_layout (rli, /*free_p=*/true);
5134 /* Warn about bases that can't be talked about due to ambiguity. */
5135 warn_about_ambiguous_bases (t);
5137 /* Now that we're done with layout, give the base fields the real types. */
5138 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
5139 if (DECL_ARTIFICIAL (field) && IS_FAKE_BASE_TYPE (TREE_TYPE (field)))
5140 TREE_TYPE (field) = TYPE_CONTEXT (TREE_TYPE (field));
5143 splay_tree_delete (empty_base_offsets);
5145 if (CLASSTYPE_EMPTY_P (t)
5146 && tree_int_cst_lt (sizeof_biggest_empty_class,
5147 TYPE_SIZE_UNIT (t)))
5148 sizeof_biggest_empty_class = TYPE_SIZE_UNIT (t);
5151 /* Determine the "key method" for the class type indicated by TYPE,
5152 and set CLASSTYPE_KEY_METHOD accordingly. */
5155 determine_key_method (tree type)
5159 if (TYPE_FOR_JAVA (type)
5160 || processing_template_decl
5161 || CLASSTYPE_TEMPLATE_INSTANTIATION (type)
5162 || CLASSTYPE_INTERFACE_KNOWN (type))
5165 /* The key method is the first non-pure virtual function that is not
5166 inline at the point of class definition. On some targets the
5167 key function may not be inline; those targets should not call
5168 this function until the end of the translation unit. */
5169 for (method = TYPE_METHODS (type); method != NULL_TREE;
5170 method = TREE_CHAIN (method))
5171 if (DECL_VINDEX (method) != NULL_TREE
5172 && ! DECL_DECLARED_INLINE_P (method)
5173 && ! DECL_PURE_VIRTUAL_P (method))
5175 CLASSTYPE_KEY_METHOD (type) = method;
5182 /* Perform processing required when the definition of T (a class type)
5186 finish_struct_1 (tree t)
5189 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5190 tree virtuals = NULL_TREE;
5193 if (COMPLETE_TYPE_P (t))
5195 gcc_assert (MAYBE_CLASS_TYPE_P (t));
5196 error ("redefinition of %q#T", t);
5201 /* If this type was previously laid out as a forward reference,
5202 make sure we lay it out again. */
5203 TYPE_SIZE (t) = NULL_TREE;
5204 CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE;
5206 fixup_inline_methods (t);
5208 /* Make assumptions about the class; we'll reset the flags if
5210 CLASSTYPE_EMPTY_P (t) = 1;
5211 CLASSTYPE_NEARLY_EMPTY_P (t) = 1;
5212 CLASSTYPE_CONTAINS_EMPTY_CLASS_P (t) = 0;
5214 /* Do end-of-class semantic processing: checking the validity of the
5215 bases and members and add implicitly generated methods. */
5216 check_bases_and_members (t);
5218 /* Find the key method. */
5219 if (TYPE_CONTAINS_VPTR_P (t))
5221 /* The Itanium C++ ABI permits the key method to be chosen when
5222 the class is defined -- even though the key method so
5223 selected may later turn out to be an inline function. On
5224 some systems (such as ARM Symbian OS) the key method cannot
5225 be determined until the end of the translation unit. On such
5226 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5227 will cause the class to be added to KEYED_CLASSES. Then, in
5228 finish_file we will determine the key method. */
5229 if (targetm.cxx.key_method_may_be_inline ())
5230 determine_key_method (t);
5232 /* If a polymorphic class has no key method, we may emit the vtable
5233 in every translation unit where the class definition appears. */
5234 if (CLASSTYPE_KEY_METHOD (t) == NULL_TREE)
5235 keyed_classes = tree_cons (NULL_TREE, t, keyed_classes);
5238 /* Layout the class itself. */
5239 layout_class_type (t, &virtuals);
5240 if (CLASSTYPE_AS_BASE (t) != t)
5241 /* We use the base type for trivial assignments, and hence it
5243 compute_record_mode (CLASSTYPE_AS_BASE (t));
5245 virtuals = modify_all_vtables (t, nreverse (virtuals));
5247 /* If necessary, create the primary vtable for this class. */
5248 if (virtuals || TYPE_CONTAINS_VPTR_P (t))
5250 /* We must enter these virtuals into the table. */
5251 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5252 build_primary_vtable (NULL_TREE, t);
5253 else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t)))
5254 /* Here we know enough to change the type of our virtual
5255 function table, but we will wait until later this function. */
5256 build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t);
5259 if (TYPE_CONTAINS_VPTR_P (t))
5264 if (BINFO_VTABLE (TYPE_BINFO (t)))
5265 gcc_assert (DECL_VIRTUAL_P (BINFO_VTABLE (TYPE_BINFO (t))));
5266 if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t))
5267 gcc_assert (BINFO_VIRTUALS (TYPE_BINFO (t)) == NULL_TREE);
5269 /* Add entries for virtual functions introduced by this class. */
5270 BINFO_VIRTUALS (TYPE_BINFO (t))
5271 = chainon (BINFO_VIRTUALS (TYPE_BINFO (t)), virtuals);
5273 /* Set DECL_VINDEX for all functions declared in this class. */
5274 for (vindex = 0, fn = BINFO_VIRTUALS (TYPE_BINFO (t));
5276 fn = TREE_CHAIN (fn),
5277 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5278 ? TARGET_VTABLE_USES_DESCRIPTORS : 1))
5280 tree fndecl = BV_FN (fn);
5282 if (DECL_THUNK_P (fndecl))
5283 /* A thunk. We should never be calling this entry directly
5284 from this vtable -- we'd use the entry for the non
5285 thunk base function. */
5286 DECL_VINDEX (fndecl) = NULL_TREE;
5287 else if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST)
5288 DECL_VINDEX (fndecl) = build_int_cst (NULL_TREE, vindex);
5292 finish_struct_bits (t);
5294 /* Complete the rtl for any static member objects of the type we're
5296 for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x))
5297 if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x)
5298 && TREE_TYPE (x) != error_mark_node
5299 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (x)), t))
5300 DECL_MODE (x) = TYPE_MODE (t);
5302 /* Done with FIELDS...now decide whether to sort these for
5303 faster lookups later.
5305 We use a small number because most searches fail (succeeding
5306 ultimately as the search bores through the inheritance
5307 hierarchy), and we want this failure to occur quickly. */
5309 n_fields = count_fields (TYPE_FIELDS (t));
5312 struct sorted_fields_type *field_vec = GGC_NEWVAR
5313 (struct sorted_fields_type,
5314 sizeof (struct sorted_fields_type) + n_fields * sizeof (tree));
5315 field_vec->len = n_fields;
5316 add_fields_to_record_type (TYPE_FIELDS (t), field_vec, 0);
5317 qsort (field_vec->elts, n_fields, sizeof (tree),
5319 if (! DECL_LANG_SPECIFIC (TYPE_MAIN_DECL (t)))
5320 retrofit_lang_decl (TYPE_MAIN_DECL (t));
5321 DECL_SORTED_FIELDS (TYPE_MAIN_DECL (t)) = field_vec;
5324 /* Complain if one of the field types requires lower visibility. */
5325 constrain_class_visibility (t);
5327 /* Make the rtl for any new vtables we have created, and unmark
5328 the base types we marked. */
5331 /* Build the VTT for T. */
5334 /* This warning does not make sense for Java classes, since they
5335 cannot have destructors. */
5336 if (!TYPE_FOR_JAVA (t) && warn_nonvdtor && TYPE_POLYMORPHIC_P (t))
5340 dtor = CLASSTYPE_DESTRUCTORS (t);
5341 if (/* An implicitly declared destructor is always public. And,
5342 if it were virtual, we would have created it by now. */
5344 || (!DECL_VINDEX (dtor)
5345 && (/* public non-virtual */
5346 (!TREE_PRIVATE (dtor) && !TREE_PROTECTED (dtor))
5347 || (/* non-public non-virtual with friends */
5348 (TREE_PRIVATE (dtor) || TREE_PROTECTED (dtor))
5349 && (CLASSTYPE_FRIEND_CLASSES (t)
5350 || DECL_FRIENDLIST (TYPE_MAIN_DECL (t)))))))
5351 warning (OPT_Wnon_virtual_dtor,
5352 "%q#T has virtual functions and accessible"
5353 " non-virtual destructor", t);
5358 if (warn_overloaded_virtual)
5361 /* Class layout, assignment of virtual table slots, etc., is now
5362 complete. Give the back end a chance to tweak the visibility of
5363 the class or perform any other required target modifications. */
5364 targetm.cxx.adjust_class_at_definition (t);
5366 maybe_suppress_debug_info (t);
5368 dump_class_hierarchy (t);
5370 /* Finish debugging output for this type. */
5371 rest_of_type_compilation (t, ! LOCAL_CLASS_P (t));
5374 /* When T was built up, the member declarations were added in reverse
5375 order. Rearrange them to declaration order. */
5378 unreverse_member_declarations (tree t)
5384 /* The following lists are all in reverse order. Put them in
5385 declaration order now. */
5386 TYPE_METHODS (t) = nreverse (TYPE_METHODS (t));
5387 CLASSTYPE_DECL_LIST (t) = nreverse (CLASSTYPE_DECL_LIST (t));
5389 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5390 reverse order, so we can't just use nreverse. */
5392 for (x = TYPE_FIELDS (t);
5393 x && TREE_CODE (x) != TYPE_DECL;
5396 next = TREE_CHAIN (x);
5397 TREE_CHAIN (x) = prev;
5402 TREE_CHAIN (TYPE_FIELDS (t)) = x;
5404 TYPE_FIELDS (t) = prev;
5409 finish_struct (tree t, tree attributes)
5411 location_t saved_loc = input_location;
5413 /* Now that we've got all the field declarations, reverse everything
5415 unreverse_member_declarations (t);
5417 cplus_decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5419 /* Nadger the current location so that diagnostics point to the start of
5420 the struct, not the end. */
5421 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (t));
5423 if (processing_template_decl)
5427 finish_struct_methods (t);
5428 TYPE_SIZE (t) = bitsize_zero_node;
5429 TYPE_SIZE_UNIT (t) = size_zero_node;
5431 /* We need to emit an error message if this type was used as a parameter
5432 and it is an abstract type, even if it is a template. We construct
5433 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5434 account and we call complete_vars with this type, which will check
5435 the PARM_DECLS. Note that while the type is being defined,
5436 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5437 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5438 CLASSTYPE_PURE_VIRTUALS (t) = NULL;
5439 for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x))
5440 if (DECL_PURE_VIRTUAL_P (x))
5441 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (t), x);
5445 finish_struct_1 (t);
5447 input_location = saved_loc;
5449 TYPE_BEING_DEFINED (t) = 0;
5451 if (current_class_type)
5454 error ("trying to finish struct, but kicked out due to previous parse errors");
5456 if (processing_template_decl && at_function_scope_p ())
5457 add_stmt (build_min (TAG_DEFN, t));
5462 /* Return the dynamic type of INSTANCE, if known.
5463 Used to determine whether the virtual function table is needed
5466 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5467 of our knowledge of its type. *NONNULL should be initialized
5468 before this function is called. */
5471 fixed_type_or_null (tree instance, int *nonnull, int *cdtorp)
5473 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5475 switch (TREE_CODE (instance))
5478 if (POINTER_TYPE_P (TREE_TYPE (instance)))
5481 return RECUR (TREE_OPERAND (instance, 0));
5484 /* This is a call to a constructor, hence it's never zero. */
5485 if (TREE_HAS_CONSTRUCTOR (instance))
5489 return TREE_TYPE (instance);
5494 /* This is a call to a constructor, hence it's never zero. */
5495 if (TREE_HAS_CONSTRUCTOR (instance))
5499 return TREE_TYPE (instance);
5501 return RECUR (TREE_OPERAND (instance, 0));
5503 case POINTER_PLUS_EXPR:
5506 if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR)
5507 return RECUR (TREE_OPERAND (instance, 0));
5508 if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST)
5509 /* Propagate nonnull. */
5510 return RECUR (TREE_OPERAND (instance, 0));
5515 return RECUR (TREE_OPERAND (instance, 0));
5518 instance = TREE_OPERAND (instance, 0);
5521 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5522 with a real object -- given &p->f, p can still be null. */
5523 tree t = get_base_address (instance);
5524 /* ??? Probably should check DECL_WEAK here. */
5525 if (t && DECL_P (t))
5528 return RECUR (instance);
5531 /* If this component is really a base class reference, then the field
5532 itself isn't definitive. */
5533 if (DECL_FIELD_IS_BASE (TREE_OPERAND (instance, 1)))
5534 return RECUR (TREE_OPERAND (instance, 0));
5535 return RECUR (TREE_OPERAND (instance, 1));
5539 if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE
5540 && MAYBE_CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (instance))))
5544 return TREE_TYPE (TREE_TYPE (instance));
5546 /* fall through... */
5550 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (instance)))
5554 return TREE_TYPE (instance);
5556 else if (instance == current_class_ptr)
5561 /* if we're in a ctor or dtor, we know our type. */
5562 if (DECL_LANG_SPECIFIC (current_function_decl)
5563 && (DECL_CONSTRUCTOR_P (current_function_decl)
5564 || DECL_DESTRUCTOR_P (current_function_decl)))
5568 return TREE_TYPE (TREE_TYPE (instance));
5571 else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5573 /* We only need one hash table because it is always left empty. */
5576 ht = htab_create (37,
5581 /* Reference variables should be references to objects. */
5585 /* Enter the INSTANCE in a table to prevent recursion; a
5586 variable's initializer may refer to the variable
5588 if (TREE_CODE (instance) == VAR_DECL
5589 && DECL_INITIAL (instance)
5590 && !htab_find (ht, instance))
5595 slot = htab_find_slot (ht, instance, INSERT);
5597 type = RECUR (DECL_INITIAL (instance));
5598 htab_remove_elt (ht, instance);
5611 /* Return nonzero if the dynamic type of INSTANCE is known, and
5612 equivalent to the static type. We also handle the case where
5613 INSTANCE is really a pointer. Return negative if this is a
5614 ctor/dtor. There the dynamic type is known, but this might not be
5615 the most derived base of the original object, and hence virtual
5616 bases may not be layed out according to this type.
5618 Used to determine whether the virtual function table is needed
5621 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5622 of our knowledge of its type. *NONNULL should be initialized
5623 before this function is called. */
5626 resolves_to_fixed_type_p (tree instance, int* nonnull)
5628 tree t = TREE_TYPE (instance);
5630 tree fixed = fixed_type_or_null (instance, nonnull, &cdtorp);
5631 if (fixed == NULL_TREE)
5633 if (POINTER_TYPE_P (t))
5635 if (!same_type_ignoring_top_level_qualifiers_p (t, fixed))
5637 return cdtorp ? -1 : 1;
5642 init_class_processing (void)
5644 current_class_depth = 0;
5645 current_class_stack_size = 10;
5647 = XNEWVEC (struct class_stack_node, current_class_stack_size);
5648 local_classes = VEC_alloc (tree, gc, 8);
5649 sizeof_biggest_empty_class = size_zero_node;
5651 ridpointers[(int) RID_PUBLIC] = access_public_node;
5652 ridpointers[(int) RID_PRIVATE] = access_private_node;
5653 ridpointers[(int) RID_PROTECTED] = access_protected_node;
5656 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5659 restore_class_cache (void)
5663 /* We are re-entering the same class we just left, so we don't
5664 have to search the whole inheritance matrix to find all the
5665 decls to bind again. Instead, we install the cached
5666 class_shadowed list and walk through it binding names. */
5667 push_binding_level (previous_class_level);
5668 class_binding_level = previous_class_level;
5669 /* Restore IDENTIFIER_TYPE_VALUE. */
5670 for (type = class_binding_level->type_shadowed;
5672 type = TREE_CHAIN (type))
5673 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (type), TREE_TYPE (type));
5676 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5677 appropriate for TYPE.
5679 So that we may avoid calls to lookup_name, we cache the _TYPE
5680 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5682 For multiple inheritance, we perform a two-pass depth-first search
5683 of the type lattice. */
5686 pushclass (tree type)
5688 class_stack_node_t csn;
5690 type = TYPE_MAIN_VARIANT (type);
5692 /* Make sure there is enough room for the new entry on the stack. */
5693 if (current_class_depth + 1 >= current_class_stack_size)
5695 current_class_stack_size *= 2;
5697 = XRESIZEVEC (struct class_stack_node, current_class_stack,
5698 current_class_stack_size);
5701 /* Insert a new entry on the class stack. */
5702 csn = current_class_stack + current_class_depth;
5703 csn->name = current_class_name;
5704 csn->type = current_class_type;
5705 csn->access = current_access_specifier;
5706 csn->names_used = 0;
5708 current_class_depth++;
5710 /* Now set up the new type. */
5711 current_class_name = TYPE_NAME (type);
5712 if (TREE_CODE (current_class_name) == TYPE_DECL)
5713 current_class_name = DECL_NAME (current_class_name);
5714 current_class_type = type;
5716 /* By default, things in classes are private, while things in
5717 structures or unions are public. */
5718 current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type)
5719 ? access_private_node
5720 : access_public_node);
5722 if (previous_class_level
5723 && type != previous_class_level->this_entity
5724 && current_class_depth == 1)
5726 /* Forcibly remove any old class remnants. */
5727 invalidate_class_lookup_cache ();
5730 if (!previous_class_level
5731 || type != previous_class_level->this_entity
5732 || current_class_depth > 1)
5735 restore_class_cache ();
5738 /* When we exit a toplevel class scope, we save its binding level so
5739 that we can restore it quickly. Here, we've entered some other
5740 class, so we must invalidate our cache. */
5743 invalidate_class_lookup_cache (void)
5745 previous_class_level = NULL;
5748 /* Get out of the current class scope. If we were in a class scope
5749 previously, that is the one popped to. */
5756 current_class_depth--;
5757 current_class_name = current_class_stack[current_class_depth].name;
5758 current_class_type = current_class_stack[current_class_depth].type;
5759 current_access_specifier = current_class_stack[current_class_depth].access;
5760 if (current_class_stack[current_class_depth].names_used)
5761 splay_tree_delete (current_class_stack[current_class_depth].names_used);
5764 /* Mark the top of the class stack as hidden. */
5767 push_class_stack (void)
5769 if (current_class_depth)
5770 ++current_class_stack[current_class_depth - 1].hidden;
5773 /* Mark the top of the class stack as un-hidden. */
5776 pop_class_stack (void)
5778 if (current_class_depth)
5779 --current_class_stack[current_class_depth - 1].hidden;
5782 /* Returns 1 if the class type currently being defined is either T or
5783 a nested type of T. */
5786 currently_open_class (tree t)
5790 if (!CLASS_TYPE_P (t))
5793 /* We start looking from 1 because entry 0 is from global scope,
5795 for (i = current_class_depth; i > 0; --i)
5798 if (i == current_class_depth)
5799 c = current_class_type;
5802 if (current_class_stack[i].hidden)
5804 c = current_class_stack[i].type;
5808 if (same_type_p (c, t))
5814 /* If either current_class_type or one of its enclosing classes are derived
5815 from T, return the appropriate type. Used to determine how we found
5816 something via unqualified lookup. */
5819 currently_open_derived_class (tree t)
5823 /* The bases of a dependent type are unknown. */
5824 if (dependent_type_p (t))
5827 if (!current_class_type)
5830 if (DERIVED_FROM_P (t, current_class_type))
5831 return current_class_type;
5833 for (i = current_class_depth - 1; i > 0; --i)
5835 if (current_class_stack[i].hidden)
5837 if (DERIVED_FROM_P (t, current_class_stack[i].type))
5838 return current_class_stack[i].type;
5844 /* When entering a class scope, all enclosing class scopes' names with
5845 static meaning (static variables, static functions, types and
5846 enumerators) have to be visible. This recursive function calls
5847 pushclass for all enclosing class contexts until global or a local
5848 scope is reached. TYPE is the enclosed class. */
5851 push_nested_class (tree type)
5853 /* A namespace might be passed in error cases, like A::B:C. */
5854 if (type == NULL_TREE
5855 || !CLASS_TYPE_P (type))
5858 push_nested_class (DECL_CONTEXT (TYPE_MAIN_DECL (type)));
5863 /* Undoes a push_nested_class call. */
5866 pop_nested_class (void)
5868 tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type));
5871 if (context && CLASS_TYPE_P (context))
5872 pop_nested_class ();
5875 /* Returns the number of extern "LANG" blocks we are nested within. */
5878 current_lang_depth (void)
5880 return VEC_length (tree, current_lang_base);
5883 /* Set global variables CURRENT_LANG_NAME to appropriate value
5884 so that behavior of name-mangling machinery is correct. */
5887 push_lang_context (tree name)
5889 VEC_safe_push (tree, gc, current_lang_base, current_lang_name);
5891 if (name == lang_name_cplusplus)
5893 current_lang_name = name;
5895 else if (name == lang_name_java)
5897 current_lang_name = name;
5898 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
5899 (See record_builtin_java_type in decl.c.) However, that causes
5900 incorrect debug entries if these types are actually used.
5901 So we re-enable debug output after extern "Java". */
5902 DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0;
5903 DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0;
5904 DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0;
5905 DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0;
5906 DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0;
5907 DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0;
5908 DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0;
5909 DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0;
5911 else if (name == lang_name_c)
5913 current_lang_name = name;
5916 error ("language string %<\"%E\"%> not recognized", name);
5919 /* Get out of the current language scope. */
5922 pop_lang_context (void)
5924 current_lang_name = VEC_pop (tree, current_lang_base);
5927 /* Type instantiation routines. */
5929 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
5930 matches the TARGET_TYPE. If there is no satisfactory match, return
5931 error_mark_node, and issue an error & warning messages under
5932 control of FLAGS. Permit pointers to member function if FLAGS
5933 permits. If TEMPLATE_ONLY, the name of the overloaded function was
5934 a template-id, and EXPLICIT_TARGS are the explicitly provided
5937 If OVERLOAD is for one or more member functions, then ACCESS_PATH
5938 is the base path used to reference those member functions. If
5939 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
5940 resolved to a member function, access checks will be performed and
5941 errors issued if appropriate. */
5944 resolve_address_of_overloaded_function (tree target_type,
5946 tsubst_flags_t flags,
5948 tree explicit_targs,
5951 /* Here's what the standard says:
5955 If the name is a function template, template argument deduction
5956 is done, and if the argument deduction succeeds, the deduced
5957 arguments are used to generate a single template function, which
5958 is added to the set of overloaded functions considered.
5960 Non-member functions and static member functions match targets of
5961 type "pointer-to-function" or "reference-to-function." Nonstatic
5962 member functions match targets of type "pointer-to-member
5963 function;" the function type of the pointer to member is used to
5964 select the member function from the set of overloaded member
5965 functions. If a nonstatic member function is selected, the
5966 reference to the overloaded function name is required to have the
5967 form of a pointer to member as described in 5.3.1.
5969 If more than one function is selected, any template functions in
5970 the set are eliminated if the set also contains a non-template
5971 function, and any given template function is eliminated if the
5972 set contains a second template function that is more specialized
5973 than the first according to the partial ordering rules 14.5.5.2.
5974 After such eliminations, if any, there shall remain exactly one
5975 selected function. */
5978 int is_reference = 0;
5979 /* We store the matches in a TREE_LIST rooted here. The functions
5980 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
5981 interoperability with most_specialized_instantiation. */
5982 tree matches = NULL_TREE;
5985 /* By the time we get here, we should be seeing only real
5986 pointer-to-member types, not the internal POINTER_TYPE to
5987 METHOD_TYPE representation. */
5988 gcc_assert (TREE_CODE (target_type) != POINTER_TYPE
5989 || TREE_CODE (TREE_TYPE (target_type)) != METHOD_TYPE);
5991 gcc_assert (is_overloaded_fn (overload));
5993 /* Check that the TARGET_TYPE is reasonable. */
5994 if (TYPE_PTRFN_P (target_type))
5996 else if (TYPE_PTRMEMFUNC_P (target_type))
5997 /* This is OK, too. */
5999 else if (TREE_CODE (target_type) == FUNCTION_TYPE)
6001 /* This is OK, too. This comes from a conversion to reference
6003 target_type = build_reference_type (target_type);
6008 if (flags & tf_error)
6009 error ("cannot resolve overloaded function %qD based on"
6010 " conversion to type %qT",
6011 DECL_NAME (OVL_FUNCTION (overload)), target_type);
6012 return error_mark_node;
6015 /* If we can find a non-template function that matches, we can just
6016 use it. There's no point in generating template instantiations
6017 if we're just going to throw them out anyhow. But, of course, we
6018 can only do this when we don't *need* a template function. */
6023 for (fns = overload; fns; fns = OVL_NEXT (fns))
6025 tree fn = OVL_CURRENT (fns);
6028 if (TREE_CODE (fn) == TEMPLATE_DECL)
6029 /* We're not looking for templates just yet. */
6032 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6034 /* We're looking for a non-static member, and this isn't
6035 one, or vice versa. */
6038 /* Ignore functions which haven't been explicitly
6040 if (DECL_ANTICIPATED (fn))
6043 /* See if there's a match. */
6044 fntype = TREE_TYPE (fn);
6046 fntype = build_ptrmemfunc_type (build_pointer_type (fntype));
6047 else if (!is_reference)
6048 fntype = build_pointer_type (fntype);
6050 if (can_convert_arg (target_type, fntype, fn, LOOKUP_NORMAL))
6051 matches = tree_cons (fn, NULL_TREE, matches);
6055 /* Now, if we've already got a match (or matches), there's no need
6056 to proceed to the template functions. But, if we don't have a
6057 match we need to look at them, too. */
6060 tree target_fn_type;
6061 tree target_arg_types;
6062 tree target_ret_type;
6067 = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (target_type));
6069 target_fn_type = TREE_TYPE (target_type);
6070 target_arg_types = TYPE_ARG_TYPES (target_fn_type);
6071 target_ret_type = TREE_TYPE (target_fn_type);
6073 /* Never do unification on the 'this' parameter. */
6074 if (TREE_CODE (target_fn_type) == METHOD_TYPE)
6075 target_arg_types = TREE_CHAIN (target_arg_types);
6077 for (fns = overload; fns; fns = OVL_NEXT (fns))
6079 tree fn = OVL_CURRENT (fns);
6081 tree instantiation_type;
6084 if (TREE_CODE (fn) != TEMPLATE_DECL)
6085 /* We're only looking for templates. */
6088 if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6090 /* We're not looking for a non-static member, and this is
6091 one, or vice versa. */
6094 /* Try to do argument deduction. */
6095 targs = make_tree_vec (DECL_NTPARMS (fn));
6096 if (fn_type_unification (fn, explicit_targs, targs,
6097 target_arg_types, target_ret_type,
6098 DEDUCE_EXACT, LOOKUP_NORMAL))
6099 /* Argument deduction failed. */
6102 /* Instantiate the template. */
6103 instantiation = instantiate_template (fn, targs, flags);
6104 if (instantiation == error_mark_node)
6105 /* Instantiation failed. */
6108 /* See if there's a match. */
6109 instantiation_type = TREE_TYPE (instantiation);
6111 instantiation_type =
6112 build_ptrmemfunc_type (build_pointer_type (instantiation_type));
6113 else if (!is_reference)
6114 instantiation_type = build_pointer_type (instantiation_type);
6115 if (can_convert_arg (target_type, instantiation_type, instantiation,
6117 matches = tree_cons (instantiation, fn, matches);
6120 /* Now, remove all but the most specialized of the matches. */
6123 tree match = most_specialized_instantiation (matches);
6125 if (match != error_mark_node)
6126 matches = tree_cons (TREE_PURPOSE (match),
6132 /* Now we should have exactly one function in MATCHES. */
6133 if (matches == NULL_TREE)
6135 /* There were *no* matches. */
6136 if (flags & tf_error)
6138 error ("no matches converting function %qD to type %q#T",
6139 DECL_NAME (OVL_FUNCTION (overload)),
6142 /* print_candidates expects a chain with the functions in
6143 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6144 so why be clever?). */
6145 for (; overload; overload = OVL_NEXT (overload))
6146 matches = tree_cons (NULL_TREE, OVL_CURRENT (overload),
6149 print_candidates (matches);
6151 return error_mark_node;
6153 else if (TREE_CHAIN (matches))
6155 /* There were too many matches. First check if they're all
6156 the same function. */
6159 fn = TREE_PURPOSE (matches);
6160 for (match = TREE_CHAIN (matches); match; match = TREE_CHAIN (match))
6161 if (!decls_match (fn, TREE_PURPOSE (match)))
6166 if (flags & tf_error)
6168 error ("converting overloaded function %qD to type %q#T is ambiguous",
6169 DECL_NAME (OVL_FUNCTION (overload)),
6172 /* Since print_candidates expects the functions in the
6173 TREE_VALUE slot, we flip them here. */
6174 for (match = matches; match; match = TREE_CHAIN (match))
6175 TREE_VALUE (match) = TREE_PURPOSE (match);
6177 print_candidates (matches);
6180 return error_mark_node;
6184 /* Good, exactly one match. Now, convert it to the correct type. */
6185 fn = TREE_PURPOSE (matches);
6187 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
6188 && !(flags & tf_ptrmem_ok) && !flag_ms_extensions)
6190 static int explained;
6192 if (!(flags & tf_error))
6193 return error_mark_node;
6195 permerror (input_location, "assuming pointer to member %qD", fn);
6198 inform (input_location, "(a pointer to member can only be formed with %<&%E%>)", fn);
6203 /* If we're doing overload resolution purely for the purpose of
6204 determining conversion sequences, we should not consider the
6205 function used. If this conversion sequence is selected, the
6206 function will be marked as used at this point. */
6207 if (!(flags & tf_conv))
6209 /* Make =delete work with SFINAE. */
6210 if (DECL_DELETED_FN (fn) && !(flags & tf_error))
6211 return error_mark_node;
6216 /* We could not check access to member functions when this
6217 expression was originally created since we did not know at that
6218 time to which function the expression referred. */
6219 if (!(flags & tf_no_access_control)
6220 && DECL_FUNCTION_MEMBER_P (fn))
6222 gcc_assert (access_path);
6223 perform_or_defer_access_check (access_path, fn, fn);
6226 if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type))
6227 return cp_build_unary_op (ADDR_EXPR, fn, 0, flags);
6230 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6231 will mark the function as addressed, but here we must do it
6233 cxx_mark_addressable (fn);
6239 /* This function will instantiate the type of the expression given in
6240 RHS to match the type of LHSTYPE. If errors exist, then return
6241 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6242 we complain on errors. If we are not complaining, never modify rhs,
6243 as overload resolution wants to try many possible instantiations, in
6244 the hope that at least one will work.
6246 For non-recursive calls, LHSTYPE should be a function, pointer to
6247 function, or a pointer to member function. */
6250 instantiate_type (tree lhstype, tree rhs, tsubst_flags_t flags)
6252 tsubst_flags_t flags_in = flags;
6253 tree access_path = NULL_TREE;
6255 flags &= ~tf_ptrmem_ok;
6257 if (TREE_CODE (lhstype) == UNKNOWN_TYPE)
6259 if (flags & tf_error)
6260 error ("not enough type information");
6261 return error_mark_node;
6264 if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs)))
6266 if (same_type_p (lhstype, TREE_TYPE (rhs)))
6268 if (flag_ms_extensions
6269 && TYPE_PTRMEMFUNC_P (lhstype)
6270 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (rhs)))
6271 /* Microsoft allows `A::f' to be resolved to a
6272 pointer-to-member. */
6276 if (flags & tf_error)
6277 error ("argument of type %qT does not match %qT",
6278 TREE_TYPE (rhs), lhstype);
6279 return error_mark_node;
6283 if (TREE_CODE (rhs) == BASELINK)
6285 access_path = BASELINK_ACCESS_BINFO (rhs);
6286 rhs = BASELINK_FUNCTIONS (rhs);
6289 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6290 deduce any type information. */
6291 if (TREE_CODE (rhs) == NON_DEPENDENT_EXPR)
6293 if (flags & tf_error)
6294 error ("not enough type information");
6295 return error_mark_node;
6298 /* There only a few kinds of expressions that may have a type
6299 dependent on overload resolution. */
6300 gcc_assert (TREE_CODE (rhs) == ADDR_EXPR
6301 || TREE_CODE (rhs) == COMPONENT_REF
6302 || TREE_CODE (rhs) == COMPOUND_EXPR
6303 || really_overloaded_fn (rhs));
6305 /* We don't overwrite rhs if it is an overloaded function.
6306 Copying it would destroy the tree link. */
6307 if (TREE_CODE (rhs) != OVERLOAD)
6308 rhs = copy_node (rhs);
6310 /* This should really only be used when attempting to distinguish
6311 what sort of a pointer to function we have. For now, any
6312 arithmetic operation which is not supported on pointers
6313 is rejected as an error. */
6315 switch (TREE_CODE (rhs))
6319 tree member = TREE_OPERAND (rhs, 1);
6321 member = instantiate_type (lhstype, member, flags);
6322 if (member != error_mark_node
6323 && TREE_SIDE_EFFECTS (TREE_OPERAND (rhs, 0)))
6324 /* Do not lose object's side effects. */
6325 return build2 (COMPOUND_EXPR, TREE_TYPE (member),
6326 TREE_OPERAND (rhs, 0), member);
6331 rhs = TREE_OPERAND (rhs, 1);
6332 if (BASELINK_P (rhs))
6333 return instantiate_type (lhstype, rhs, flags_in);
6335 /* This can happen if we are forming a pointer-to-member for a
6337 gcc_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR);
6341 case TEMPLATE_ID_EXPR:
6343 tree fns = TREE_OPERAND (rhs, 0);
6344 tree args = TREE_OPERAND (rhs, 1);
6347 resolve_address_of_overloaded_function (lhstype, fns, flags_in,
6348 /*template_only=*/true,
6355 resolve_address_of_overloaded_function (lhstype, rhs, flags_in,
6356 /*template_only=*/false,
6357 /*explicit_targs=*/NULL_TREE,
6361 TREE_OPERAND (rhs, 0)
6362 = instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6363 if (TREE_OPERAND (rhs, 0) == error_mark_node)
6364 return error_mark_node;
6365 TREE_OPERAND (rhs, 1)
6366 = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags);
6367 if (TREE_OPERAND (rhs, 1) == error_mark_node)
6368 return error_mark_node;
6370 TREE_TYPE (rhs) = lhstype;
6375 if (PTRMEM_OK_P (rhs))
6376 flags |= tf_ptrmem_ok;
6378 return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags);
6382 return error_mark_node;
6387 return error_mark_node;
6390 /* Return the name of the virtual function pointer field
6391 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6392 this may have to look back through base types to find the
6393 ultimate field name. (For single inheritance, these could
6394 all be the same name. Who knows for multiple inheritance). */
6397 get_vfield_name (tree type)
6399 tree binfo, base_binfo;
6402 for (binfo = TYPE_BINFO (type);
6403 BINFO_N_BASE_BINFOS (binfo);
6406 base_binfo = BINFO_BASE_BINFO (binfo, 0);
6408 if (BINFO_VIRTUAL_P (base_binfo)
6409 || !TYPE_CONTAINS_VPTR_P (BINFO_TYPE (base_binfo)))
6413 type = BINFO_TYPE (binfo);
6414 buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT)
6415 + TYPE_NAME_LENGTH (type) + 2);
6416 sprintf (buf, VFIELD_NAME_FORMAT,
6417 IDENTIFIER_POINTER (constructor_name (type)));
6418 return get_identifier (buf);
6422 print_class_statistics (void)
6424 #ifdef GATHER_STATISTICS
6425 fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness);
6426 fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs);
6429 fprintf (stderr, "vtables = %d; vtable searches = %d\n",
6430 n_vtables, n_vtable_searches);
6431 fprintf (stderr, "vtable entries = %d; vtable elems = %d\n",
6432 n_vtable_entries, n_vtable_elems);
6437 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6438 according to [class]:
6439 The class-name is also inserted
6440 into the scope of the class itself. For purposes of access checking,
6441 the inserted class name is treated as if it were a public member name. */
6444 build_self_reference (void)
6446 tree name = constructor_name (current_class_type);
6447 tree value = build_lang_decl (TYPE_DECL, name, current_class_type);
6450 DECL_NONLOCAL (value) = 1;
6451 DECL_CONTEXT (value) = current_class_type;
6452 DECL_ARTIFICIAL (value) = 1;
6453 SET_DECL_SELF_REFERENCE_P (value);
6455 if (processing_template_decl)
6456 value = push_template_decl (value);
6458 saved_cas = current_access_specifier;
6459 current_access_specifier = access_public_node;
6460 finish_member_declaration (value);
6461 current_access_specifier = saved_cas;
6464 /* Returns 1 if TYPE contains only padding bytes. */
6467 is_empty_class (tree type)
6469 if (type == error_mark_node)
6472 if (! CLASS_TYPE_P (type))
6475 /* In G++ 3.2, whether or not a class was empty was determined by
6476 looking at its size. */
6477 if (abi_version_at_least (2))
6478 return CLASSTYPE_EMPTY_P (type);
6480 return integer_zerop (CLASSTYPE_SIZE (type));
6483 /* Returns true if TYPE contains an empty class. */
6486 contains_empty_class_p (tree type)
6488 if (is_empty_class (type))
6490 if (CLASS_TYPE_P (type))
6497 for (binfo = TYPE_BINFO (type), i = 0;
6498 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6499 if (contains_empty_class_p (BINFO_TYPE (base_binfo)))
6501 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6502 if (TREE_CODE (field) == FIELD_DECL
6503 && !DECL_ARTIFICIAL (field)
6504 && is_empty_class (TREE_TYPE (field)))
6507 else if (TREE_CODE (type) == ARRAY_TYPE)
6508 return contains_empty_class_p (TREE_TYPE (type));
6512 /* Returns true if TYPE contains no actual data, just various
6513 possible combinations of empty classes. */
6516 is_really_empty_class (tree type)
6518 if (is_empty_class (type))
6520 if (CLASS_TYPE_P (type))
6527 for (binfo = TYPE_BINFO (type), i = 0;
6528 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
6529 if (!is_really_empty_class (BINFO_TYPE (base_binfo)))
6531 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6532 if (TREE_CODE (field) == FIELD_DECL
6533 && !DECL_ARTIFICIAL (field)
6534 && !is_really_empty_class (TREE_TYPE (field)))
6538 else if (TREE_CODE (type) == ARRAY_TYPE)
6539 return is_really_empty_class (TREE_TYPE (type));
6543 /* Note that NAME was looked up while the current class was being
6544 defined and that the result of that lookup was DECL. */
6547 maybe_note_name_used_in_class (tree name, tree decl)
6549 splay_tree names_used;
6551 /* If we're not defining a class, there's nothing to do. */
6552 if (!(innermost_scope_kind() == sk_class
6553 && TYPE_BEING_DEFINED (current_class_type)))
6556 /* If there's already a binding for this NAME, then we don't have
6557 anything to worry about. */
6558 if (lookup_member (current_class_type, name,
6559 /*protect=*/0, /*want_type=*/false))
6562 if (!current_class_stack[current_class_depth - 1].names_used)
6563 current_class_stack[current_class_depth - 1].names_used
6564 = splay_tree_new (splay_tree_compare_pointers, 0, 0);
6565 names_used = current_class_stack[current_class_depth - 1].names_used;
6567 splay_tree_insert (names_used,
6568 (splay_tree_key) name,
6569 (splay_tree_value) decl);
6572 /* Note that NAME was declared (as DECL) in the current class. Check
6573 to see that the declaration is valid. */
6576 note_name_declared_in_class (tree name, tree decl)
6578 splay_tree names_used;
6581 /* Look to see if we ever used this name. */
6583 = current_class_stack[current_class_depth - 1].names_used;
6587 n = splay_tree_lookup (names_used, (splay_tree_key) name);
6590 /* [basic.scope.class]
6592 A name N used in a class S shall refer to the same declaration
6593 in its context and when re-evaluated in the completed scope of
6595 permerror (input_location, "declaration of %q#D", decl);
6596 permerror (input_location, "changes meaning of %qD from %q+#D",
6597 DECL_NAME (OVL_CURRENT (decl)), (tree) n->value);
6601 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6602 Secondary vtables are merged with primary vtables; this function
6603 will return the VAR_DECL for the primary vtable. */
6606 get_vtbl_decl_for_binfo (tree binfo)
6610 decl = BINFO_VTABLE (binfo);
6611 if (decl && TREE_CODE (decl) == POINTER_PLUS_EXPR)
6613 gcc_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR);
6614 decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0);
6617 gcc_assert (TREE_CODE (decl) == VAR_DECL);
6622 /* Returns the binfo for the primary base of BINFO. If the resulting
6623 BINFO is a virtual base, and it is inherited elsewhere in the
6624 hierarchy, then the returned binfo might not be the primary base of
6625 BINFO in the complete object. Check BINFO_PRIMARY_P or
6626 BINFO_LOST_PRIMARY_P to be sure. */
6629 get_primary_binfo (tree binfo)
6633 primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo));
6637 return copied_binfo (primary_base, binfo);
6640 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6643 maybe_indent_hierarchy (FILE * stream, int indent, int indented_p)
6646 fprintf (stream, "%*s", indent, "");
6650 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6651 INDENT should be zero when called from the top level; it is
6652 incremented recursively. IGO indicates the next expected BINFO in
6653 inheritance graph ordering. */
6656 dump_class_hierarchy_r (FILE *stream,
6666 indented = maybe_indent_hierarchy (stream, indent, 0);
6667 fprintf (stream, "%s (0x%lx) ",
6668 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER),
6669 (unsigned long) binfo);
6672 fprintf (stream, "alternative-path\n");
6675 igo = TREE_CHAIN (binfo);
6677 fprintf (stream, HOST_WIDE_INT_PRINT_DEC,
6678 tree_low_cst (BINFO_OFFSET (binfo), 0));
6679 if (is_empty_class (BINFO_TYPE (binfo)))
6680 fprintf (stream, " empty");
6681 else if (CLASSTYPE_NEARLY_EMPTY_P (BINFO_TYPE (binfo)))
6682 fprintf (stream, " nearly-empty");
6683 if (BINFO_VIRTUAL_P (binfo))
6684 fprintf (stream, " virtual");
6685 fprintf (stream, "\n");
6688 if (BINFO_PRIMARY_P (binfo))
6690 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6691 fprintf (stream, " primary-for %s (0x%lx)",
6692 type_as_string (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)),
6693 TFF_PLAIN_IDENTIFIER),
6694 (unsigned long)BINFO_INHERITANCE_CHAIN (binfo));
6696 if (BINFO_LOST_PRIMARY_P (binfo))
6698 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6699 fprintf (stream, " lost-primary");
6702 fprintf (stream, "\n");
6704 if (!(flags & TDF_SLIM))
6708 if (BINFO_SUBVTT_INDEX (binfo))
6710 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6711 fprintf (stream, " subvttidx=%s",
6712 expr_as_string (BINFO_SUBVTT_INDEX (binfo),
6713 TFF_PLAIN_IDENTIFIER));
6715 if (BINFO_VPTR_INDEX (binfo))
6717 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6718 fprintf (stream, " vptridx=%s",
6719 expr_as_string (BINFO_VPTR_INDEX (binfo),
6720 TFF_PLAIN_IDENTIFIER));
6722 if (BINFO_VPTR_FIELD (binfo))
6724 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6725 fprintf (stream, " vbaseoffset=%s",
6726 expr_as_string (BINFO_VPTR_FIELD (binfo),
6727 TFF_PLAIN_IDENTIFIER));
6729 if (BINFO_VTABLE (binfo))
6731 indented = maybe_indent_hierarchy (stream, indent + 3, indented);
6732 fprintf (stream, " vptr=%s",
6733 expr_as_string (BINFO_VTABLE (binfo),
6734 TFF_PLAIN_IDENTIFIER));
6738 fprintf (stream, "\n");
6741 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
6742 igo = dump_class_hierarchy_r (stream, flags, base_binfo, igo, indent + 2);
6747 /* Dump the BINFO hierarchy for T. */
6750 dump_class_hierarchy_1 (FILE *stream, int flags, tree t)
6752 fprintf (stream, "Class %s\n", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6753 fprintf (stream, " size=%lu align=%lu\n",
6754 (unsigned long)(tree_low_cst (TYPE_SIZE (t), 0) / BITS_PER_UNIT),
6755 (unsigned long)(TYPE_ALIGN (t) / BITS_PER_UNIT));
6756 fprintf (stream, " base size=%lu base align=%lu\n",
6757 (unsigned long)(tree_low_cst (TYPE_SIZE (CLASSTYPE_AS_BASE (t)), 0)
6759 (unsigned long)(TYPE_ALIGN (CLASSTYPE_AS_BASE (t))
6761 dump_class_hierarchy_r (stream, flags, TYPE_BINFO (t), TYPE_BINFO (t), 0);
6762 fprintf (stream, "\n");
6765 /* Debug interface to hierarchy dumping. */
6768 debug_class (tree t)
6770 dump_class_hierarchy_1 (stderr, TDF_SLIM, t);
6774 dump_class_hierarchy (tree t)
6777 FILE *stream = dump_begin (TDI_class, &flags);
6781 dump_class_hierarchy_1 (stream, flags, t);
6782 dump_end (TDI_class, stream);
6787 dump_array (FILE * stream, tree decl)
6790 unsigned HOST_WIDE_INT ix;
6792 tree size = TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (decl)));
6794 elt = (tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl))), 0)
6796 fprintf (stream, "%s:", decl_as_string (decl, TFF_PLAIN_IDENTIFIER));
6797 fprintf (stream, " %s entries",
6798 expr_as_string (size_binop (PLUS_EXPR, size, size_one_node),
6799 TFF_PLAIN_IDENTIFIER));
6800 fprintf (stream, "\n");
6802 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
6804 fprintf (stream, "%-4ld %s\n", (long)(ix * elt),
6805 expr_as_string (value, TFF_PLAIN_IDENTIFIER));
6809 dump_vtable (tree t, tree binfo, tree vtable)
6812 FILE *stream = dump_begin (TDI_class, &flags);
6817 if (!(flags & TDF_SLIM))
6819 int ctor_vtbl_p = TYPE_BINFO (t) != binfo;
6821 fprintf (stream, "%s for %s",
6822 ctor_vtbl_p ? "Construction vtable" : "Vtable",
6823 type_as_string (BINFO_TYPE (binfo), TFF_PLAIN_IDENTIFIER));
6826 if (!BINFO_VIRTUAL_P (binfo))
6827 fprintf (stream, " (0x%lx instance)", (unsigned long)binfo);
6828 fprintf (stream, " in %s", type_as_string (t, TFF_PLAIN_IDENTIFIER));
6830 fprintf (stream, "\n");
6831 dump_array (stream, vtable);
6832 fprintf (stream, "\n");
6835 dump_end (TDI_class, stream);
6839 dump_vtt (tree t, tree vtt)
6842 FILE *stream = dump_begin (TDI_class, &flags);
6847 if (!(flags & TDF_SLIM))
6849 fprintf (stream, "VTT for %s\n",
6850 type_as_string (t, TFF_PLAIN_IDENTIFIER));
6851 dump_array (stream, vtt);
6852 fprintf (stream, "\n");
6855 dump_end (TDI_class, stream);
6858 /* Dump a function or thunk and its thunkees. */
6861 dump_thunk (FILE *stream, int indent, tree thunk)
6863 static const char spaces[] = " ";
6864 tree name = DECL_NAME (thunk);
6867 fprintf (stream, "%.*s%p %s %s", indent, spaces,
6869 !DECL_THUNK_P (thunk) ? "function"
6870 : DECL_THIS_THUNK_P (thunk) ? "this-thunk" : "covariant-thunk",
6871 name ? IDENTIFIER_POINTER (name) : "<unset>");
6872 if (DECL_THUNK_P (thunk))
6874 HOST_WIDE_INT fixed_adjust = THUNK_FIXED_OFFSET (thunk);
6875 tree virtual_adjust = THUNK_VIRTUAL_OFFSET (thunk);
6877 fprintf (stream, " fixed=" HOST_WIDE_INT_PRINT_DEC, fixed_adjust);
6878 if (!virtual_adjust)
6880 else if (DECL_THIS_THUNK_P (thunk))
6881 fprintf (stream, " vcall=" HOST_WIDE_INT_PRINT_DEC,
6882 tree_low_cst (virtual_adjust, 0));
6884 fprintf (stream, " vbase=" HOST_WIDE_INT_PRINT_DEC "(%s)",
6885 tree_low_cst (BINFO_VPTR_FIELD (virtual_adjust), 0),
6886 type_as_string (BINFO_TYPE (virtual_adjust), TFF_SCOPE));
6887 if (THUNK_ALIAS (thunk))
6888 fprintf (stream, " alias to %p", (void *)THUNK_ALIAS (thunk));
6890 fprintf (stream, "\n");
6891 for (thunks = DECL_THUNKS (thunk); thunks; thunks = TREE_CHAIN (thunks))
6892 dump_thunk (stream, indent + 2, thunks);
6895 /* Dump the thunks for FN. */
6898 debug_thunks (tree fn)
6900 dump_thunk (stderr, 0, fn);
6903 /* Virtual function table initialization. */
6905 /* Create all the necessary vtables for T and its base classes. */
6908 finish_vtbls (tree t)
6913 /* We lay out the primary and secondary vtables in one contiguous
6914 vtable. The primary vtable is first, followed by the non-virtual
6915 secondary vtables in inheritance graph order. */
6916 list = build_tree_list (BINFO_VTABLE (TYPE_BINFO (t)), NULL_TREE);
6917 accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t),
6918 TYPE_BINFO (t), t, list);
6920 /* Then come the virtual bases, also in inheritance graph order. */
6921 for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase))
6923 if (!BINFO_VIRTUAL_P (vbase))
6925 accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list);
6928 if (BINFO_VTABLE (TYPE_BINFO (t)))
6929 initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list));
6932 /* Initialize the vtable for BINFO with the INITS. */
6935 initialize_vtable (tree binfo, tree inits)
6939 layout_vtable_decl (binfo, list_length (inits));
6940 decl = get_vtbl_decl_for_binfo (binfo);
6941 initialize_artificial_var (decl, inits);
6942 dump_vtable (BINFO_TYPE (binfo), binfo, decl);
6945 /* Build the VTT (virtual table table) for T.
6946 A class requires a VTT if it has virtual bases.
6949 1 - primary virtual pointer for complete object T
6950 2 - secondary VTTs for each direct non-virtual base of T which requires a
6952 3 - secondary virtual pointers for each direct or indirect base of T which
6953 has virtual bases or is reachable via a virtual path from T.
6954 4 - secondary VTTs for each direct or indirect virtual base of T.
6956 Secondary VTTs look like complete object VTTs without part 4. */
6966 /* Build up the initializers for the VTT. */
6968 index = size_zero_node;
6969 build_vtt_inits (TYPE_BINFO (t), t, &inits, &index);
6971 /* If we didn't need a VTT, we're done. */
6975 /* Figure out the type of the VTT. */
6976 type = build_index_type (size_int (list_length (inits) - 1));
6977 type = build_cplus_array_type (const_ptr_type_node, type);
6979 /* Now, build the VTT object itself. */
6980 vtt = build_vtable (t, mangle_vtt_for_type (t), type);
6981 initialize_artificial_var (vtt, inits);
6982 /* Add the VTT to the vtables list. */
6983 TREE_CHAIN (vtt) = TREE_CHAIN (CLASSTYPE_VTABLES (t));
6984 TREE_CHAIN (CLASSTYPE_VTABLES (t)) = vtt;
6989 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
6990 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
6991 and CHAIN the vtable pointer for this binfo after construction is
6992 complete. VALUE can also be another BINFO, in which case we recurse. */
6995 binfo_ctor_vtable (tree binfo)
7001 vt = BINFO_VTABLE (binfo);
7002 if (TREE_CODE (vt) == TREE_LIST)
7003 vt = TREE_VALUE (vt);
7004 if (TREE_CODE (vt) == TREE_BINFO)
7013 /* Data for secondary VTT initialization. */
7014 typedef struct secondary_vptr_vtt_init_data_s
7016 /* Is this the primary VTT? */
7019 /* Current index into the VTT. */
7022 /* TREE_LIST of initializers built up. */
7025 /* The type being constructed by this secondary VTT. */
7026 tree type_being_constructed;
7027 } secondary_vptr_vtt_init_data;
7029 /* Recursively build the VTT-initializer for BINFO (which is in the
7030 hierarchy dominated by T). INITS points to the end of the initializer
7031 list to date. INDEX is the VTT index where the next element will be
7032 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7033 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7034 for virtual bases of T. When it is not so, we build the constructor
7035 vtables for the BINFO-in-T variant. */
7038 build_vtt_inits (tree binfo, tree t, tree *inits, tree *index)
7043 tree secondary_vptrs;
7044 secondary_vptr_vtt_init_data data;
7045 int top_level_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7047 /* We only need VTTs for subobjects with virtual bases. */
7048 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7051 /* We need to use a construction vtable if this is not the primary
7055 build_ctor_vtbl_group (binfo, t);
7057 /* Record the offset in the VTT where this sub-VTT can be found. */
7058 BINFO_SUBVTT_INDEX (binfo) = *index;
7061 /* Add the address of the primary vtable for the complete object. */
7062 init = binfo_ctor_vtable (binfo);
7063 *inits = build_tree_list (NULL_TREE, init);
7064 inits = &TREE_CHAIN (*inits);
7067 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7068 BINFO_VPTR_INDEX (binfo) = *index;
7070 *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node));
7072 /* Recursively add the secondary VTTs for non-virtual bases. */
7073 for (i = 0; BINFO_BASE_ITERATE (binfo, i, b); ++i)
7074 if (!BINFO_VIRTUAL_P (b))
7075 inits = build_vtt_inits (b, t, inits, index);
7077 /* Add secondary virtual pointers for all subobjects of BINFO with
7078 either virtual bases or reachable along a virtual path, except
7079 subobjects that are non-virtual primary bases. */
7080 data.top_level_p = top_level_p;
7081 data.index = *index;
7083 data.type_being_constructed = BINFO_TYPE (binfo);
7085 dfs_walk_once (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, &data);
7087 *index = data.index;
7089 /* The secondary vptrs come back in reverse order. After we reverse
7090 them, and add the INITS, the last init will be the first element
7092 secondary_vptrs = data.inits;
7093 if (secondary_vptrs)
7095 *inits = nreverse (secondary_vptrs);
7096 inits = &TREE_CHAIN (secondary_vptrs);
7097 gcc_assert (*inits == NULL_TREE);
7101 /* Add the secondary VTTs for virtual bases in inheritance graph
7103 for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b))
7105 if (!BINFO_VIRTUAL_P (b))
7108 inits = build_vtt_inits (b, t, inits, index);
7111 /* Remove the ctor vtables we created. */
7112 dfs_walk_all (binfo, dfs_fixup_binfo_vtbls, NULL, binfo);
7117 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7118 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7121 dfs_build_secondary_vptr_vtt_inits (tree binfo, void *data_)
7123 secondary_vptr_vtt_init_data *data = (secondary_vptr_vtt_init_data *)data_;
7125 /* We don't care about bases that don't have vtables. */
7126 if (!TYPE_VFIELD (BINFO_TYPE (binfo)))
7127 return dfs_skip_bases;
7129 /* We're only interested in proper subobjects of the type being
7131 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->type_being_constructed))
7134 /* We're only interested in bases with virtual bases or reachable
7135 via a virtual path from the type being constructed. */
7136 if (!(CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7137 || binfo_via_virtual (binfo, data->type_being_constructed)))
7138 return dfs_skip_bases;
7140 /* We're not interested in non-virtual primary bases. */
7141 if (!BINFO_VIRTUAL_P (binfo) && BINFO_PRIMARY_P (binfo))
7144 /* Record the index where this secondary vptr can be found. */
7145 if (data->top_level_p)
7147 gcc_assert (!BINFO_VPTR_INDEX (binfo));
7148 BINFO_VPTR_INDEX (binfo) = data->index;
7150 if (BINFO_VIRTUAL_P (binfo))
7152 /* It's a primary virtual base, and this is not a
7153 construction vtable. Find the base this is primary of in
7154 the inheritance graph, and use that base's vtable
7156 while (BINFO_PRIMARY_P (binfo))
7157 binfo = BINFO_INHERITANCE_CHAIN (binfo);
7161 /* Add the initializer for the secondary vptr itself. */
7162 data->inits = tree_cons (NULL_TREE, binfo_ctor_vtable (binfo), data->inits);
7164 /* Advance the vtt index. */
7165 data->index = size_binop (PLUS_EXPR, data->index,
7166 TYPE_SIZE_UNIT (ptr_type_node));
7171 /* Called from build_vtt_inits via dfs_walk. After building
7172 constructor vtables and generating the sub-vtt from them, we need
7173 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7174 binfo of the base whose sub vtt was generated. */
7177 dfs_fixup_binfo_vtbls (tree binfo, void* data)
7179 tree vtable = BINFO_VTABLE (binfo);
7181 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7182 /* If this class has no vtable, none of its bases do. */
7183 return dfs_skip_bases;
7186 /* This might be a primary base, so have no vtable in this
7190 /* If we scribbled the construction vtable vptr into BINFO, clear it
7192 if (TREE_CODE (vtable) == TREE_LIST
7193 && (TREE_PURPOSE (vtable) == (tree) data))
7194 BINFO_VTABLE (binfo) = TREE_CHAIN (vtable);
7199 /* Build the construction vtable group for BINFO which is in the
7200 hierarchy dominated by T. */
7203 build_ctor_vtbl_group (tree binfo, tree t)
7212 /* See if we've already created this construction vtable group. */
7213 id = mangle_ctor_vtbl_for_type (t, binfo);
7214 if (IDENTIFIER_GLOBAL_VALUE (id))
7217 gcc_assert (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t));
7218 /* Build a version of VTBL (with the wrong type) for use in
7219 constructing the addresses of secondary vtables in the
7220 construction vtable group. */
7221 vtbl = build_vtable (t, id, ptr_type_node);
7222 DECL_CONSTRUCTION_VTABLE_P (vtbl) = 1;
7223 list = build_tree_list (vtbl, NULL_TREE);
7224 accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)),
7227 /* Add the vtables for each of our virtual bases using the vbase in T
7229 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7231 vbase = TREE_CHAIN (vbase))
7235 if (!BINFO_VIRTUAL_P (vbase))
7237 b = copied_binfo (vbase, binfo);
7239 accumulate_vtbl_inits (b, vbase, binfo, t, list);
7241 inits = TREE_VALUE (list);
7243 /* Figure out the type of the construction vtable. */
7244 type = build_index_type (size_int (list_length (inits) - 1));
7245 type = build_cplus_array_type (vtable_entry_type, type);
7247 TREE_TYPE (vtbl) = type;
7248 DECL_SIZE (vtbl) = DECL_SIZE_UNIT (vtbl) = NULL_TREE;
7249 layout_decl (vtbl, 0);
7251 /* Initialize the construction vtable. */
7252 CLASSTYPE_VTABLES (t) = chainon (CLASSTYPE_VTABLES (t), vtbl);
7253 initialize_artificial_var (vtbl, inits);
7254 dump_vtable (t, binfo, vtbl);
7257 /* Add the vtbl initializers for BINFO (and its bases other than
7258 non-virtual primaries) to the list of INITS. BINFO is in the
7259 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7260 the constructor the vtbl inits should be accumulated for. (If this
7261 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7262 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7263 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7264 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7265 but are not necessarily the same in terms of layout. */
7268 accumulate_vtbl_inits (tree binfo,
7276 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7278 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)));
7280 /* If it doesn't have a vptr, we don't do anything. */
7281 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
7284 /* If we're building a construction vtable, we're not interested in
7285 subobjects that don't require construction vtables. */
7287 && !CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo))
7288 && !binfo_via_virtual (orig_binfo, BINFO_TYPE (rtti_binfo)))
7291 /* Build the initializers for the BINFO-in-T vtable. */
7293 = chainon (TREE_VALUE (inits),
7294 dfs_accumulate_vtbl_inits (binfo, orig_binfo,
7295 rtti_binfo, t, inits));
7297 /* Walk the BINFO and its bases. We walk in preorder so that as we
7298 initialize each vtable we can figure out at what offset the
7299 secondary vtable lies from the primary vtable. We can't use
7300 dfs_walk here because we need to iterate through bases of BINFO
7301 and RTTI_BINFO simultaneously. */
7302 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7304 /* Skip virtual bases. */
7305 if (BINFO_VIRTUAL_P (base_binfo))
7307 accumulate_vtbl_inits (base_binfo,
7308 BINFO_BASE_BINFO (orig_binfo, i),
7314 /* Called from accumulate_vtbl_inits. Returns the initializers for
7315 the BINFO vtable. */
7318 dfs_accumulate_vtbl_inits (tree binfo,
7324 tree inits = NULL_TREE;
7325 tree vtbl = NULL_TREE;
7326 int ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7329 && BINFO_VIRTUAL_P (orig_binfo) && BINFO_PRIMARY_P (orig_binfo))
7331 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7332 primary virtual base. If it is not the same primary in
7333 the hierarchy of T, we'll need to generate a ctor vtable
7334 for it, to place at its location in T. If it is the same
7335 primary, we still need a VTT entry for the vtable, but it
7336 should point to the ctor vtable for the base it is a
7337 primary for within the sub-hierarchy of RTTI_BINFO.
7339 There are three possible cases:
7341 1) We are in the same place.
7342 2) We are a primary base within a lost primary virtual base of
7344 3) We are primary to something not a base of RTTI_BINFO. */
7347 tree last = NULL_TREE;
7349 /* First, look through the bases we are primary to for RTTI_BINFO
7350 or a virtual base. */
7352 while (BINFO_PRIMARY_P (b))
7354 b = BINFO_INHERITANCE_CHAIN (b);
7356 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7359 /* If we run out of primary links, keep looking down our
7360 inheritance chain; we might be an indirect primary. */
7361 for (b = last; b; b = BINFO_INHERITANCE_CHAIN (b))
7362 if (BINFO_VIRTUAL_P (b) || b == rtti_binfo)
7366 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7367 base B and it is a base of RTTI_BINFO, this is case 2. In
7368 either case, we share our vtable with LAST, i.e. the
7369 derived-most base within B of which we are a primary. */
7371 || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
7372 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7373 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7374 binfo_ctor_vtable after everything's been set up. */
7377 /* Otherwise, this is case 3 and we get our own. */
7379 else if (!BINFO_NEW_VTABLE_MARKED (orig_binfo))
7387 /* Compute the initializer for this vtable. */
7388 inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo,
7391 /* Figure out the position to which the VPTR should point. */
7392 vtbl = TREE_PURPOSE (l);
7393 vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl);
7394 index = size_binop (PLUS_EXPR,
7395 size_int (non_fn_entries),
7396 size_int (list_length (TREE_VALUE (l))));
7397 index = size_binop (MULT_EXPR,
7398 TYPE_SIZE_UNIT (vtable_entry_type),
7400 vtbl = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index);
7404 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7405 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7406 straighten this out. */
7407 BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo));
7408 else if (BINFO_PRIMARY_P (binfo) && BINFO_VIRTUAL_P (binfo))
7411 /* For an ordinary vtable, set BINFO_VTABLE. */
7412 BINFO_VTABLE (binfo) = vtbl;
7417 static GTY(()) tree abort_fndecl_addr;
7419 /* Construct the initializer for BINFO's virtual function table. BINFO
7420 is part of the hierarchy dominated by T. If we're building a
7421 construction vtable, the ORIG_BINFO is the binfo we should use to
7422 find the actual function pointers to put in the vtable - but they
7423 can be overridden on the path to most-derived in the graph that
7424 ORIG_BINFO belongs. Otherwise,
7425 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7426 BINFO that should be indicated by the RTTI information in the
7427 vtable; it will be a base class of T, rather than T itself, if we
7428 are building a construction vtable.
7430 The value returned is a TREE_LIST suitable for wrapping in a
7431 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7432 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7433 number of non-function entries in the vtable.
7435 It might seem that this function should never be called with a
7436 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7437 base is always subsumed by a derived class vtable. However, when
7438 we are building construction vtables, we do build vtables for
7439 primary bases; we need these while the primary base is being
7443 build_vtbl_initializer (tree binfo,
7447 int* non_fn_entries_p)
7454 VEC(tree,gc) *vbases;
7456 /* Initialize VID. */
7457 memset (&vid, 0, sizeof (vid));
7460 vid.rtti_binfo = rtti_binfo;
7461 vid.last_init = &vid.inits;
7462 vid.primary_vtbl_p = SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), t);
7463 vid.ctor_vtbl_p = !SAME_BINFO_TYPE_P (BINFO_TYPE (rtti_binfo), t);
7464 vid.generate_vcall_entries = true;
7465 /* The first vbase or vcall offset is at index -3 in the vtable. */
7466 vid.index = ssize_int(-3 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
7468 /* Add entries to the vtable for RTTI. */
7469 build_rtti_vtbl_entries (binfo, &vid);
7471 /* Create an array for keeping track of the functions we've
7472 processed. When we see multiple functions with the same
7473 signature, we share the vcall offsets. */
7474 vid.fns = VEC_alloc (tree, gc, 32);
7475 /* Add the vcall and vbase offset entries. */
7476 build_vcall_and_vbase_vtbl_entries (binfo, &vid);
7478 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7479 build_vbase_offset_vtbl_entries. */
7480 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
7481 VEC_iterate (tree, vbases, ix, vbinfo); ix++)
7482 BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
7484 /* If the target requires padding between data entries, add that now. */
7485 if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)
7489 for (prev = &vid.inits; (cur = *prev); prev = &TREE_CHAIN (cur))
7494 for (i = 1; i < TARGET_VTABLE_DATA_ENTRY_DISTANCE; ++i)
7495 add = tree_cons (NULL_TREE,
7496 build1 (NOP_EXPR, vtable_entry_type,
7503 if (non_fn_entries_p)
7504 *non_fn_entries_p = list_length (vid.inits);
7506 /* Go through all the ordinary virtual functions, building up
7508 vfun_inits = NULL_TREE;
7509 for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v))
7513 tree fn, fn_original;
7514 tree init = NULL_TREE;
7518 if (DECL_THUNK_P (fn))
7520 if (!DECL_NAME (fn))
7522 if (THUNK_ALIAS (fn))
7524 fn = THUNK_ALIAS (fn);
7527 fn_original = THUNK_TARGET (fn);
7530 /* If the only definition of this function signature along our
7531 primary base chain is from a lost primary, this vtable slot will
7532 never be used, so just zero it out. This is important to avoid
7533 requiring extra thunks which cannot be generated with the function.
7535 We first check this in update_vtable_entry_for_fn, so we handle
7536 restored primary bases properly; we also need to do it here so we
7537 zero out unused slots in ctor vtables, rather than filling them
7538 with erroneous values (though harmless, apart from relocation
7540 for (b = binfo; ; b = get_primary_binfo (b))
7542 /* We found a defn before a lost primary; go ahead as normal. */
7543 if (look_for_overrides_here (BINFO_TYPE (b), fn_original))
7546 /* The nearest definition is from a lost primary; clear the
7548 if (BINFO_LOST_PRIMARY_P (b))
7550 init = size_zero_node;
7557 /* Pull the offset for `this', and the function to call, out of
7559 delta = BV_DELTA (v);
7560 vcall_index = BV_VCALL_INDEX (v);
7562 gcc_assert (TREE_CODE (delta) == INTEGER_CST);
7563 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7565 /* You can't call an abstract virtual function; it's abstract.
7566 So, we replace these functions with __pure_virtual. */
7567 if (DECL_PURE_VIRTUAL_P (fn_original))
7570 if (abort_fndecl_addr == NULL)
7571 abort_fndecl_addr = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7572 init = abort_fndecl_addr;
7576 if (!integer_zerop (delta) || vcall_index)
7578 fn = make_thunk (fn, /*this_adjusting=*/1, delta, vcall_index);
7579 if (!DECL_NAME (fn))
7582 /* Take the address of the function, considering it to be of an
7583 appropriate generic type. */
7584 init = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn);
7588 /* And add it to the chain of initializers. */
7589 if (TARGET_VTABLE_USES_DESCRIPTORS)
7592 if (init == size_zero_node)
7593 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7594 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7596 for (i = 0; i < TARGET_VTABLE_USES_DESCRIPTORS; ++i)
7598 tree fdesc = build2 (FDESC_EXPR, vfunc_ptr_type_node,
7599 TREE_OPERAND (init, 0),
7600 build_int_cst (NULL_TREE, i));
7601 TREE_CONSTANT (fdesc) = 1;
7603 vfun_inits = tree_cons (NULL_TREE, fdesc, vfun_inits);
7607 vfun_inits = tree_cons (NULL_TREE, init, vfun_inits);
7610 /* The initializers for virtual functions were built up in reverse
7611 order; straighten them out now. */
7612 vfun_inits = nreverse (vfun_inits);
7614 /* The negative offset initializers are also in reverse order. */
7615 vid.inits = nreverse (vid.inits);
7617 /* Chain the two together. */
7618 return chainon (vid.inits, vfun_inits);
7621 /* Adds to vid->inits the initializers for the vbase and vcall
7622 offsets in BINFO, which is in the hierarchy dominated by T. */
7625 build_vcall_and_vbase_vtbl_entries (tree binfo, vtbl_init_data* vid)
7629 /* If this is a derived class, we must first create entries
7630 corresponding to the primary base class. */
7631 b = get_primary_binfo (binfo);
7633 build_vcall_and_vbase_vtbl_entries (b, vid);
7635 /* Add the vbase entries for this base. */
7636 build_vbase_offset_vtbl_entries (binfo, vid);
7637 /* Add the vcall entries for this base. */
7638 build_vcall_offset_vtbl_entries (binfo, vid);
7641 /* Returns the initializers for the vbase offset entries in the vtable
7642 for BINFO (which is part of the class hierarchy dominated by T), in
7643 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7644 where the next vbase offset will go. */
7647 build_vbase_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7651 tree non_primary_binfo;
7653 /* If there are no virtual baseclasses, then there is nothing to
7655 if (!CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)))
7660 /* We might be a primary base class. Go up the inheritance hierarchy
7661 until we find the most derived class of which we are a primary base:
7662 it is the offset of that which we need to use. */
7663 non_primary_binfo = binfo;
7664 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7668 /* If we have reached a virtual base, then it must be a primary
7669 base (possibly multi-level) of vid->binfo, or we wouldn't
7670 have called build_vcall_and_vbase_vtbl_entries for it. But it
7671 might be a lost primary, so just skip down to vid->binfo. */
7672 if (BINFO_VIRTUAL_P (non_primary_binfo))
7674 non_primary_binfo = vid->binfo;
7678 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7679 if (get_primary_binfo (b) != non_primary_binfo)
7681 non_primary_binfo = b;
7684 /* Go through the virtual bases, adding the offsets. */
7685 for (vbase = TYPE_BINFO (BINFO_TYPE (binfo));
7687 vbase = TREE_CHAIN (vbase))
7692 if (!BINFO_VIRTUAL_P (vbase))
7695 /* Find the instance of this virtual base in the complete
7697 b = copied_binfo (vbase, binfo);
7699 /* If we've already got an offset for this virtual base, we
7700 don't need another one. */
7701 if (BINFO_VTABLE_PATH_MARKED (b))
7703 BINFO_VTABLE_PATH_MARKED (b) = 1;
7705 /* Figure out where we can find this vbase offset. */
7706 delta = size_binop (MULT_EXPR,
7709 TYPE_SIZE_UNIT (vtable_entry_type)));
7710 if (vid->primary_vtbl_p)
7711 BINFO_VPTR_FIELD (b) = delta;
7713 if (binfo != TYPE_BINFO (t))
7714 /* The vbase offset had better be the same. */
7715 gcc_assert (tree_int_cst_equal (delta, BINFO_VPTR_FIELD (vbase)));
7717 /* The next vbase will come at a more negative offset. */
7718 vid->index = size_binop (MINUS_EXPR, vid->index,
7719 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7721 /* The initializer is the delta from BINFO to this virtual base.
7722 The vbase offsets go in reverse inheritance-graph order, and
7723 we are walking in inheritance graph order so these end up in
7725 delta = size_diffop (BINFO_OFFSET (b), BINFO_OFFSET (non_primary_binfo));
7728 = build_tree_list (NULL_TREE,
7729 fold_build1 (NOP_EXPR,
7732 vid->last_init = &TREE_CHAIN (*vid->last_init);
7736 /* Adds the initializers for the vcall offset entries in the vtable
7737 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7741 build_vcall_offset_vtbl_entries (tree binfo, vtbl_init_data* vid)
7743 /* We only need these entries if this base is a virtual base. We
7744 compute the indices -- but do not add to the vtable -- when
7745 building the main vtable for a class. */
7746 if (binfo == TYPE_BINFO (vid->derived)
7747 || (BINFO_VIRTUAL_P (binfo)
7748 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7749 correspond to VID->DERIVED), we are building a primary
7750 construction virtual table. Since this is a primary
7751 virtual table, we do not need the vcall offsets for
7753 && binfo != vid->rtti_binfo))
7755 /* We need a vcall offset for each of the virtual functions in this
7756 vtable. For example:
7758 class A { virtual void f (); };
7759 class B1 : virtual public A { virtual void f (); };
7760 class B2 : virtual public A { virtual void f (); };
7761 class C: public B1, public B2 { virtual void f (); };
7763 A C object has a primary base of B1, which has a primary base of A. A
7764 C also has a secondary base of B2, which no longer has a primary base
7765 of A. So the B2-in-C construction vtable needs a secondary vtable for
7766 A, which will adjust the A* to a B2* to call f. We have no way of
7767 knowing what (or even whether) this offset will be when we define B2,
7768 so we store this "vcall offset" in the A sub-vtable and look it up in
7769 a "virtual thunk" for B2::f.
7771 We need entries for all the functions in our primary vtable and
7772 in our non-virtual bases' secondary vtables. */
7774 /* If we are just computing the vcall indices -- but do not need
7775 the actual entries -- not that. */
7776 if (!BINFO_VIRTUAL_P (binfo))
7777 vid->generate_vcall_entries = false;
7778 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7779 add_vcall_offset_vtbl_entries_r (binfo, vid);
7783 /* Build vcall offsets, starting with those for BINFO. */
7786 add_vcall_offset_vtbl_entries_r (tree binfo, vtbl_init_data* vid)
7792 /* Don't walk into virtual bases -- except, of course, for the
7793 virtual base for which we are building vcall offsets. Any
7794 primary virtual base will have already had its offsets generated
7795 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7796 if (BINFO_VIRTUAL_P (binfo) && vid->vbase != binfo)
7799 /* If BINFO has a primary base, process it first. */
7800 primary_binfo = get_primary_binfo (binfo);
7802 add_vcall_offset_vtbl_entries_r (primary_binfo, vid);
7804 /* Add BINFO itself to the list. */
7805 add_vcall_offset_vtbl_entries_1 (binfo, vid);
7807 /* Scan the non-primary bases of BINFO. */
7808 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
7809 if (base_binfo != primary_binfo)
7810 add_vcall_offset_vtbl_entries_r (base_binfo, vid);
7813 /* Called from build_vcall_offset_vtbl_entries_r. */
7816 add_vcall_offset_vtbl_entries_1 (tree binfo, vtbl_init_data* vid)
7818 /* Make entries for the rest of the virtuals. */
7819 if (abi_version_at_least (2))
7823 /* The ABI requires that the methods be processed in declaration
7824 order. G++ 3.2 used the order in the vtable. */
7825 for (orig_fn = TYPE_METHODS (BINFO_TYPE (binfo));
7827 orig_fn = TREE_CHAIN (orig_fn))
7828 if (DECL_VINDEX (orig_fn))
7829 add_vcall_offset (orig_fn, binfo, vid);
7833 tree derived_virtuals;
7836 /* If BINFO is a primary base, the most derived class which has
7837 BINFO as a primary base; otherwise, just BINFO. */
7838 tree non_primary_binfo;
7840 /* We might be a primary base class. Go up the inheritance hierarchy
7841 until we find the most derived class of which we are a primary base:
7842 it is the BINFO_VIRTUALS there that we need to consider. */
7843 non_primary_binfo = binfo;
7844 while (BINFO_INHERITANCE_CHAIN (non_primary_binfo))
7848 /* If we have reached a virtual base, then it must be vid->vbase,
7849 because we ignore other virtual bases in
7850 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7851 base (possibly multi-level) of vid->binfo, or we wouldn't
7852 have called build_vcall_and_vbase_vtbl_entries for it. But it
7853 might be a lost primary, so just skip down to vid->binfo. */
7854 if (BINFO_VIRTUAL_P (non_primary_binfo))
7856 gcc_assert (non_primary_binfo == vid->vbase);
7857 non_primary_binfo = vid->binfo;
7861 b = BINFO_INHERITANCE_CHAIN (non_primary_binfo);
7862 if (get_primary_binfo (b) != non_primary_binfo)
7864 non_primary_binfo = b;
7867 if (vid->ctor_vtbl_p)
7868 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7869 where rtti_binfo is the most derived type. */
7871 = original_binfo (non_primary_binfo, vid->rtti_binfo);
7873 for (base_virtuals = BINFO_VIRTUALS (binfo),
7874 derived_virtuals = BINFO_VIRTUALS (non_primary_binfo),
7875 orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo)));
7877 base_virtuals = TREE_CHAIN (base_virtuals),
7878 derived_virtuals = TREE_CHAIN (derived_virtuals),
7879 orig_virtuals = TREE_CHAIN (orig_virtuals))
7883 /* Find the declaration that originally caused this function to
7884 be present in BINFO_TYPE (binfo). */
7885 orig_fn = BV_FN (orig_virtuals);
7887 /* When processing BINFO, we only want to generate vcall slots for
7888 function slots introduced in BINFO. So don't try to generate
7889 one if the function isn't even defined in BINFO. */
7890 if (!SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), DECL_CONTEXT (orig_fn)))
7893 add_vcall_offset (orig_fn, binfo, vid);
7898 /* Add a vcall offset entry for ORIG_FN to the vtable. */
7901 add_vcall_offset (tree orig_fn, tree binfo, vtbl_init_data *vid)
7907 /* If there is already an entry for a function with the same
7908 signature as FN, then we do not need a second vcall offset.
7909 Check the list of functions already present in the derived
7911 for (i = 0; VEC_iterate (tree, vid->fns, i, derived_entry); ++i)
7913 if (same_signature_p (derived_entry, orig_fn)
7914 /* We only use one vcall offset for virtual destructors,
7915 even though there are two virtual table entries. */
7916 || (DECL_DESTRUCTOR_P (derived_entry)
7917 && DECL_DESTRUCTOR_P (orig_fn)))
7921 /* If we are building these vcall offsets as part of building
7922 the vtable for the most derived class, remember the vcall
7924 if (vid->binfo == TYPE_BINFO (vid->derived))
7926 tree_pair_p elt = VEC_safe_push (tree_pair_s, gc,
7927 CLASSTYPE_VCALL_INDICES (vid->derived),
7929 elt->purpose = orig_fn;
7930 elt->value = vid->index;
7933 /* The next vcall offset will be found at a more negative
7935 vid->index = size_binop (MINUS_EXPR, vid->index,
7936 ssize_int (TARGET_VTABLE_DATA_ENTRY_DISTANCE));
7938 /* Keep track of this function. */
7939 VEC_safe_push (tree, gc, vid->fns, orig_fn);
7941 if (vid->generate_vcall_entries)
7946 /* Find the overriding function. */
7947 fn = find_final_overrider (vid->rtti_binfo, binfo, orig_fn);
7948 if (fn == error_mark_node)
7949 vcall_offset = build1 (NOP_EXPR, vtable_entry_type,
7953 base = TREE_VALUE (fn);
7955 /* The vbase we're working on is a primary base of
7956 vid->binfo. But it might be a lost primary, so its
7957 BINFO_OFFSET might be wrong, so we just use the
7958 BINFO_OFFSET from vid->binfo. */
7959 vcall_offset = size_diffop (BINFO_OFFSET (base),
7960 BINFO_OFFSET (vid->binfo));
7961 vcall_offset = fold_build1 (NOP_EXPR, vtable_entry_type,
7964 /* Add the initializer to the vtable. */
7965 *vid->last_init = build_tree_list (NULL_TREE, vcall_offset);
7966 vid->last_init = &TREE_CHAIN (*vid->last_init);
7970 /* Return vtbl initializers for the RTTI entries corresponding to the
7971 BINFO's vtable. The RTTI entries should indicate the object given
7972 by VID->rtti_binfo. */
7975 build_rtti_vtbl_entries (tree binfo, vtbl_init_data* vid)
7984 basetype = BINFO_TYPE (binfo);
7985 t = BINFO_TYPE (vid->rtti_binfo);
7987 /* To find the complete object, we will first convert to our most
7988 primary base, and then add the offset in the vtbl to that value. */
7990 while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))
7991 && !BINFO_LOST_PRIMARY_P (b))
7995 primary_base = get_primary_binfo (b);
7996 gcc_assert (BINFO_PRIMARY_P (primary_base)
7997 && BINFO_INHERITANCE_CHAIN (primary_base) == b);
8000 offset = size_diffop (BINFO_OFFSET (vid->rtti_binfo), BINFO_OFFSET (b));
8002 /* The second entry is the address of the typeinfo object. */
8004 decl = build_address (get_tinfo_decl (t));
8006 decl = integer_zero_node;
8008 /* Convert the declaration to a type that can be stored in the
8010 init = build_nop (vfunc_ptr_type_node, decl);
8011 *vid->last_init = build_tree_list (NULL_TREE, init);
8012 vid->last_init = &TREE_CHAIN (*vid->last_init);
8014 /* Add the offset-to-top entry. It comes earlier in the vtable than
8015 the typeinfo entry. Convert the offset to look like a
8016 function pointer, so that we can put it in the vtable. */
8017 init = build_nop (vfunc_ptr_type_node, offset);
8018 *vid->last_init = build_tree_list (NULL_TREE, init);
8019 vid->last_init = &TREE_CHAIN (*vid->last_init);
8022 /* Fold a OBJ_TYPE_REF expression to the address of a function.
8023 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
8026 cp_fold_obj_type_ref (tree ref, tree known_type)
8028 HOST_WIDE_INT index = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
8029 HOST_WIDE_INT i = 0;
8030 tree v = BINFO_VIRTUALS (TYPE_BINFO (known_type));
8035 i += (TARGET_VTABLE_USES_DESCRIPTORS
8036 ? TARGET_VTABLE_USES_DESCRIPTORS : 1);
8042 #ifdef ENABLE_CHECKING
8043 gcc_assert (tree_int_cst_equal (OBJ_TYPE_REF_TOKEN (ref),
8044 DECL_VINDEX (fndecl)));
8047 cgraph_node (fndecl)->local.vtable_method = true;
8049 return build_address (fndecl);
8052 #include "gt-cp-class.h"