| blob | 87f8111f15fece47d6cf46819ef21fb50584a108 |
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, 2010
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)
12 any later version.
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. */
41 /* The number of nested classes being processed. If we are not in the
42 scope of any class, this is zero. */
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 */
51 /* The name of the class. */
52 tree name;
54 /* The _TYPE node for the class. */
55 tree type;
57 /* The access specifier pending for new declarations in the scope of
58 this class. */
59 tree access;
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
65 push_to_top_level. */
70 {
71 /* The base for which we're building initializers. */
72 tree binfo;
73 /* The type of the most-derived type. */
74 tree derived;
75 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
76 unless ctor_vtbl_p is true. */
77 tree rtti_binfo;
78 /* The negative-index vtable initializers built up so far. These
79 are in order from least negative index to most negative index. */
80 tree inits;
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. */
85 tree vbase;
86 /* The functions in vbase for which we have already provided vcall
87 offsets. */
89 /* The vtable index of the next vcall or vbase offset. */
90 tree index;
91 /* Nonzero if we are building the initializer for the primary
92 vtable. */
94 /* Nonzero if we are building the initializer for a construction
95 vtable. */
97 /* True when adding vcall offset entries to the vtable. False when
98 merely computing the indices. */
102 /* The type of a function passed to walk_subobject_offsets. */
105 /* The stack itself. This is a dynamically resized array. The
106 number of elements allocated is CURRENT_CLASS_STACK_SIZE. */
110 /* The size of the largest empty class seen in this translation unit. */
113 /* An array of all local classes present in this translation unit, in
114 declaration order. */
183 tree);
202 splay_tree_key k2);
211 /* Variables shared between class.c and call.c. */
213 #ifdef GATHER_STATISTICS
221 #endif
223 /* Convert to or from a base subobject. EXPR is an expression of type
224 `A' or `A*', an expression of type `B' or `B*' is returned. To
225 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
226 the B base instance within A. To convert base A to derived B, CODE
227 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
228 In this latter case, A must not be a morally virtual base of B.
229 NONNULL is true if EXPR is known to be non-NULL (this is only
230 needed when EXPR is of pointer type). CV qualifiers are preserved
231 from EXPR. */
233 tree
235 tree expr,
236 tree binfo,
238 {
241 tree probe;
242 tree offset;
243 tree target_type;
245 tree ptr_target_type;
255 {
261 }
273 /* Nothing to do. */
277 {
281 }
284 /* This must happen before the call to save_expr. */
291 /* Do we need to look in the vtable for the real offset? */
294 /* Don't bother with the calculations inside sizeof; they'll ICE if the
295 source type is incomplete and the pointer value doesn't matter. */
297 {
302 }
304 /* Do we need to check for a null pointer? */
306 {
307 /* If we know the conversion will not actually change the value
308 of EXPR, then we can avoid testing the expression for NULL.
309 We have to avoid generating a COMPONENT_REF for a base class
310 field, because other parts of the compiler know that such
311 expressions are always non-NULL. */
313 {
314 tree class_type;
315 /* TARGET_TYPE has been extracted from BINFO, and, is
316 therefore always cv-unqualified. Extract the
317 cv-qualifiers from EXPR so that the expression returned
318 matches the input. */
320 target_type
324 }
326 }
328 /* Protect against multiple evaluation if necessary. */
332 /* Now that we've saved expr, build the real null test. */
334 {
338 }
340 /* If this is a simple base reference, express it as a COMPONENT_REF. */
342 /* We don't build base fields for empty bases, and they aren't very
343 interesting to the optimizers anyway. */
345 {
352 }
355 {
356 /* Going via virtual base V_BINFO. We need the static offset
357 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
358 V_BINFO. That offset is an entry in D_BINFO's vtable. */
359 tree v_offset;
362 {
363 /* In a base member initializer, we cannot rely on the
364 vtable being set up. We have to indirect via the
365 vtt_parm. */
366 tree t;
372 tf_warning_or_error);
373 }
374 else
376 tf_warning_or_error),
383 v_offset);
395 /* Negative fixed_type_p means this is a constructor or destructor;
396 virtual base layout is fixed in in-charge [cd]tors, but not in
397 base [cd]tors. */
401 v_offset,
404 else
406 }
408 target_type = cp_build_qualified_type
417 {
422 }
423 else
429 out:
433 integer_zero_node));
436 }
438 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
439 Perform a derived-to-base conversion by recursively building up a
440 sequence of COMPONENT_REFs to the appropriate base fields. */
442 static tree
444 {
447 tree field;
450 {
451 tree temp;
455 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
456 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
457 an lvalue in the front end; only _DECLs and _REFs are lvalues
458 in the back end. */
464 }
466 /* Recurse. */
471 /* Is this the base field created by build_base_field? */
475 {
476 /* We don't use build_class_member_access_expr here, as that
477 has unnecessary checks, and more importantly results in
478 recursive calls to dfs_walk_once. */
486 /* Mark the expression const or volatile, as appropriate.
487 Even though we've dealt with the type above, we still have
488 to mark the expression itself. */
495 }
497 /* Didn't find the base field?!? */
499 }
501 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
502 type is a class type or a pointer to a class type. In the former
503 case, TYPE is also a class type; in the latter it is another
504 pointer type. If CHECK_ACCESS is true, an error message is emitted
505 if TYPE is inaccessible. If OBJECT has pointer type, the value is
506 assumed to be non-NULL. */
508 tree
510 tsubst_flags_t complain)
511 {
512 tree binfo;
513 tree object_type;
514 base_access access;
517 {
520 }
521 else
528 access,
529 NULL);
534 }
536 /* EXPR is an expression with unqualified class type. BASE is a base
537 binfo of that class type. Returns EXPR, converted to the BASE
538 type. This function assumes that EXPR is the most derived class;
539 therefore virtual bases can be found at their static offsets. */
541 tree
543 {
544 tree expr_type;
548 {
549 tree pointer_type;
553 /* We use fold_build2 and fold_convert below to simplify the trees
554 provided to the optimizers. It is not safe to call these functions
555 when processing a template because they do not handle C++-specific
556 trees. */
559 tf_warning_or_error);
566 }
569 }
571 \f
572 tree
574 {
580 /* First, convert to the requested type. */
585 /* Second, the requested type may not be the owner of its own vptr.
586 If not, convert to the base class that owns it. We cannot use
587 convert_to_base here, because VCONTEXT may appear more than once
588 in the inheritance hierarchy of TYPE, and thus direct conversion
589 between the types may be ambiguous. Following the path back up
590 one step at a time via primary bases avoids the problem. */
594 {
597 }
600 }
602 /* Given an object INSTANCE, return an expression which yields the
603 vtable element corresponding to INDEX. There are many special
604 cases for INSTANCE which we take care of here, mainly to avoid
605 creating extra tree nodes when we don't have to. */
607 static tree
609 {
610 tree aref;
613 /* Try to figure out what a reference refers to, and
614 access its virtual function table directly. */
622 {
627 }
636 }
638 tree
640 {
644 }
646 /* Given a stable object pointer INSTANCE_PTR, return an expression which
647 yields a function pointer corresponding to vtable element INDEX. */
649 tree
651 {
652 tree aref;
655 tf_warning_or_error),
656 idx);
658 /* When using function descriptors, the address of the
659 vtable entry is treated as a function pointer. */
663 tf_warning_or_error));
665 /* Remember this as a method reference, for later devirtualization. */
669 }
671 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
672 for the given TYPE. */
674 static tree
676 {
678 }
680 /* DECL is an entity associated with TYPE, like a virtual table or an
681 implicitly generated constructor. Determine whether or not DECL
682 should have external or internal linkage at the object file
683 level. This routine does not deal with COMDAT linkage and other
684 similar complexities; it simply sets TREE_PUBLIC if it possible for
685 entities in other translation units to contain copies of DECL, in
686 the abstract. */
688 void
690 {
691 /* If TYPE involves a local class in a function with internal
692 linkage, then DECL should have internal linkage too. Other local
693 classes have no linkage -- but if their containing functions
694 have external linkage, it makes sense for DECL to have external
695 linkage too. That will allow template definitions to be merged,
696 for example. */
698 {
701 }
702 else
704 }
706 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
707 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
708 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
710 static tree
712 {
713 tree decl;
716 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
717 now to avoid confusion in mangle_decl. */
726 /* At one time the vtable info was grabbed 2 words at a time. This
727 fails on sparc unless you have 8-byte alignment. (tiemann) */
731 /* The vtable has not been defined -- yet. */
735 /* Mark the VAR_DECL node representing the vtable itself as a
736 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
737 is rather important that such things be ignored because any
738 effort to actually generate DWARF for them will run into
739 trouble when/if we encounter code like:
741 #pragma interface
742 struct S { virtual void member (); };
744 because the artificial declaration of the vtable itself (as
745 manufactured by the g++ front end) will say that the vtable is
746 a static member of `S' but only *after* the debug output for
747 the definition of `S' has already been output. This causes
748 grief because the DWARF entry for the definition of the vtable
749 will try to refer back to an earlier *declaration* of the
750 vtable as a static member of `S' and there won't be one. We
751 might be able to arrange to have the "vtable static member"
752 attached to the member list for `S' before the debug info for
753 `S' get written (which would solve the problem) but that would
754 require more intrusive changes to the g++ front end. */
758 }
760 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
761 or even complete. If this does not exist, create it. If COMPLETE is
762 nonzero, then complete the definition of it -- that will render it
763 impossible to actually build the vtable, but is useful to get at those
764 which are known to exist in the runtime. */
766 tree
768 {
769 tree decl;
778 {
781 }
784 }
786 /* Build the primary virtual function table for TYPE. If BINFO is
787 non-NULL, build the vtable starting with the initial approximation
788 that it is the same as the one which is the head of the association
789 list. Returns a nonzero value if a new vtable is actually
790 created. */
792 static int
794 {
795 tree decl;
796 tree virtuals;
801 {
803 /* We have already created a vtable for this base, so there's
804 no need to do it again. */
811 }
812 else
813 {
816 }
818 #ifdef GATHER_STATISTICS
821 #endif
823 /* Initialize the association list for this type, based
824 on our first approximation. */
829 }
831 /* Give BINFO a new virtual function table which is initialized
832 with a skeleton-copy of its original initialization. The only
833 entry that changes is the `delta' entry, so we can really
834 share a lot of structure.
836 FOR_TYPE is the most derived type which caused this table to
837 be needed.
839 Returns nonzero if we haven't met BINFO before.
841 The order in which vtables are built (by calling this function) for
842 an object must remain the same, otherwise a binary incompatibility
843 can result. */
845 static int
847 {
849 /* We already created a vtable for this base. There's no need to
850 do it again. */
853 /* Remember that we've created a vtable for this BINFO, so that we
854 don't try to do so again. */
857 /* Make fresh virtual list, so we can smash it later. */
860 /* Secondary vtables are laid out as part of the same structure as
861 the primary vtable. */
864 }
866 /* Create a new vtable for BINFO which is the hierarchy dominated by
867 T. Return nonzero if we actually created a new vtable. */
869 static int
871 {
873 /* In this case, it is *type*'s vtable we are modifying. We start
874 with the approximation that its vtable is that of the
875 immediate base class. */
877 else
878 /* This is our very own copy of `basetype' to play with. Later,
879 we will fill in all the virtual functions that override the
880 virtual functions in these base classes which are not defined
881 by the current type. */
883 }
885 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
886 (which is in the hierarchy dominated by T) list FNDECL as its
887 BV_FN. DELTA is the required constant adjustment from the `this'
888 pointer where the vtable entry appears to the `this' required when
889 the function is actually called. */
891 static void
893 tree binfo,
894 tree fndecl,
895 tree delta,
897 {
898 tree v;
904 {
905 /* We need a new vtable for BINFO. */
907 {
908 /* If we really did make a new vtable, we also made a copy
909 of the BINFO_VIRTUALS list. Now, we have to find the
910 corresponding entry in that list. */
915 }
920 }
921 }
923 \f
924 /* Add method METHOD to class TYPE. If USING_DECL is non-null, it is
925 the USING_DECL naming METHOD. Returns true if the method could be
926 added to the method vec. */
928 bool
930 {
932 tree overload;
938 tree current_fns;
939 tree fns;
952 {
953 /* Make a new method vector. We start with 8 entries. We must
954 allocate at least two (for constructors and destructors), and
955 we're going to end up with an assignment operator at some
956 point as well. */
958 /* Create slots for constructors and destructors. */
962 }
964 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
967 /* Constructors and destructors go in special slots. */
971 {
975 {
981 type);
982 }
983 }
984 else
985 {
986 tree m;
989 /* See if we already have an entry with this name. */
993 {
996 {
1001 }
1005 {
1008 }
1013 }
1014 }
1017 /* Check to see if we've already got this method. */
1019 {
1021 tree fn_type;
1022 tree method_type;
1023 tree parms1;
1024 tree parms2;
1029 /* [over.load] Member function declarations with the
1030 same name and the same parameter types cannot be
1031 overloaded if any of them is a static member
1032 function declaration.
1034 [namespace.udecl] When a using-declaration brings names
1035 from a base class into a derived class scope, member
1036 functions in the derived class override and/or hide member
1037 functions with the same name and parameter types in a base
1038 class (rather than conflicting). */
1044 /* Compare the quals on the 'this' parm. Don't compare
1045 the whole types, as used functions are treated as
1046 coming from the using class in overload resolution. */
1055 /* For templates, the return type and template parameters
1056 must be identical. */
1073 {
1075 {
1077 /* Defer to the local function. */
1081 else
1083 using_decl);
1084 }
1085 else
1086 {
1089 }
1091 /* We don't call duplicate_decls here to merge the
1092 declarations because that will confuse things if the
1093 methods have inline definitions. In particular, we
1094 will crash while processing the definitions. */
1096 }
1097 }
1099 /* A class should never have more than one destructor. */
1103 /* Add the new binding. */
1112 {
1115 /* We only expect to add few methods in the COMPLETE_P case, so
1116 just make room for one more method in that case. */
1119 else
1125 else
1127 }
1128 else
1129 /* Replace the current slot. */
1132 }
1134 /* Subroutines of finish_struct. */
1136 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1137 legit, otherwise return 0. */
1139 static int
1141 {
1142 tree elem;
1151 {
1153 {
1157 else
1160 }
1161 else
1162 {
1163 /* They're changing the access to the same thing they changed
1164 it to before. That's OK. */
1165 ;
1166 }
1167 }
1168 else
1169 {
1173 }
1175 }
1177 /* Process the USING_DECL, which is a member of T. */
1179 static void
1181 {
1184 tree access
1189 tree old_value;
1195 {
1201 else
1203 }
1211 ;
1213 {
1215 /* It's OK to use functions from a base when there are functions with
1217 else
1218 {
1223 }
1224 }
1226 {
1230 }
1232 /* Make type T see field decl FDECL with access ACCESS. */
1235 {
1238 }
1239 else
1241 }
1242 \f
1243 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1244 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1245 properties of the bases. */
1247 static void
1251 {
1254 tree base_binfo;
1255 tree binfo;
1267 {
1272 /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P
1273 here because the case of virtual functions but non-virtual
1274 dtor is handled in finish_struct_1. */
1279 /* If the base class doesn't have copy constructors or
1280 assignment operators that take const references, then the
1281 derived class cannot have such a member automatically
1282 generated. */
1290 /* A virtual base does not effect nearly emptiness. */
1291 ;
1293 {
1295 /* And if there is more than one nearly empty base, then the
1296 derived class is not nearly empty either. */
1298 else
1299 /* Remember we've seen one. */
1301 }
1303 /* If the base class is not empty or nearly empty, then this
1304 class cannot be nearly empty. */
1307 /* A lot of properties from the bases also apply to the derived
1308 class. */
1320 /* A standard-layout class is a class that:
1321 ...
1322 * has no non-standard-layout base classes, */
1325 {
1326 tree basefield;
1327 /* ...has no base classes of the same type as the first non-static
1328 data member... */
1330 && (same_type_ignoring_top_level_qualifiers_p
1333 else
1334 /* ...either has no non-static data members in the most-derived
1335 class and at most one base class with non-static data
1336 members, or has no base classes with non-static data
1337 members */
1341 {
1344 else
1347 }
1348 }
1349 }
1350 }
1352 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1353 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1354 that have had a nearly-empty virtual primary base stolen by some
1355 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1356 T. */
1358 static void
1360 {
1364 tree base_binfo;
1366 /* Determine the primary bases of our bases. */
1369 {
1372 /* See if we're the non-virtual primary of our inheritance
1373 chain. */
1375 {
1382 /* We are the primary binfo. */
1384 }
1385 /* Determine if we have a virtual primary base, and mark it so.
1386 */
1388 {
1392 /* Someone already claimed this base. */
1394 else
1395 {
1396 tree delta;
1401 /* A virtual binfo might have been copied from within
1402 another hierarchy. As we're about to use it as a
1403 primary base, make sure the offsets match. */
1411 }
1412 }
1413 }
1415 /* First look for a dynamic direct non-virtual base. */
1417 {
1421 {
1424 }
1425 }
1427 /* A "nearly-empty" virtual base class can be the primary base
1428 class, if no non-virtual polymorphic base can be found. Look for
1429 a nearly-empty virtual dynamic base that is not already a primary
1430 base of something in the hierarchy. If there is no such base,
1431 just pick the first nearly-empty virtual base. */
1437 {
1439 {
1440 /* Found one that is not primary. */
1443 }
1445 /* Remember the first candidate. */
1447 }
1449 found:
1450 /* If we've got a primary base, use it. */
1452 {
1457 /* We are stealing a primary base. */
1461 {
1462 tree delta;
1465 /* A virtual binfo might have been copied from within
1466 another hierarchy. As we're about to use it as a primary
1467 base, make sure the offsets match. */
1472 }
1479 }
1480 }
1482 /* Update the variant types of T. */
1484 void
1486 {
1487 tree variants;
1493 variants;
1495 {
1496 /* These fields are in the _TYPE part of the node, not in
1497 the TYPE_LANG_SPECIFIC component, so they are not shared. */
1507 /* Copy whatever these are holding today. */
1512 /* All variants of a class have the same attributes. */
1514 }
1515 }
1517 \f
1518 /* Set memoizing fields and bits of T (and its variants) for later
1519 use. */
1521 static void
1523 {
1524 /* Fix up variants (if any). */
1528 /* For a class w/o baseclasses, 'finish_struct' has set
1529 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
1530 Similarly for a class whose base classes do not have vtables.
1531 When neither of these is true, we might have removed abstract
1532 virtuals (by providing a definition), added some (by declaring
1533 new ones), or redeclared ones from a base class. We need to
1534 recalculate what's really an abstract virtual at this point (by
1535 looking in the vtables). */
1538 /* If this type has a copy constructor or a destructor, force its
1539 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
1540 nonzero. This will cause it to be passed by invisible reference
1541 and prevent it from being returned in a register. */
1543 {
1544 tree variants;
1547 {
1550 }
1551 }
1552 }
1554 /* Issue warnings about T having private constructors, but no friends,
1555 and so forth.
1557 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
1558 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
1559 non-private static member functions. */
1561 static void
1563 {
1566 tree fn;
1569 /* If the class has friends, those entities might create and
1570 access instances, so we should not warn. */
1573 /* We will have warned when the template was declared; there's
1574 no need to warn on every instantiation. */
1576 /* There's no reason to even consider warning about this
1577 class. */
1580 /* We only issue one warning, if more than one applies, because
1581 otherwise, on code like:
1583 class A {
1584 // Oops - forgot `public:'
1585 A();
1586 A(const A&);
1587 ~A();
1588 };
1590 we warn several times about essentially the same problem. */
1592 /* Check to see if all (non-constructor, non-destructor) member
1593 functions are private. (Since there are no friends or
1594 non-private statics, we can't ever call any of the private member
1595 functions.) */
1597 /* We're not interested in compiler-generated methods; they don't
1598 provide any way to call private members. */
1600 {
1602 {
1604 /* A non-private static member function is just like a
1605 friend; it can create and invoke private member
1606 functions, and be accessed without a class
1607 instance. */
1611 /* Keep searching for a static member function. */
1612 }
1615 }
1618 {
1619 /* There are no non-private methods, and there's at least one
1620 private member function that isn't a constructor or
1621 destructor. (If all the private members are
1622 constructors/destructors we want to use the code below that
1623 issues error messages specifically referring to
1624 constructors/destructors.) */
1630 {
1633 }
1635 {
1639 }
1640 }
1642 /* Even if some of the member functions are non-private, the class
1643 won't be useful for much if all the constructors or destructors
1644 are private: such an object can never be created or destroyed. */
1647 {
1650 t);
1652 }
1654 /* Warn about classes that have private constructors and no friends. */
1656 /* Implicitly generated constructors are always public. */
1659 {
1662 /* If a non-template class does not define a copy
1663 constructor, one is defined for it, enabling it to avoid
1664 this warning. For a template class, this does not
1665 happen, and so we would normally get a warning on:
1667 template <class T> class C { private: C(); };
1669 To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All
1670 complete non-template or fully instantiated classes have this
1671 flag set. */
1674 else
1676 {
1678 /* Ideally, we wouldn't count copy constructors (or, in
1679 fact, any constructor that takes an argument of the
1680 class type as a parameter) because such things cannot
1681 be used to construct an instance of the class unless
1682 you already have one. But, for now at least, we're
1683 more generous. */
1685 {
1688 }
1689 }
1692 {
1695 t);
1697 }
1698 }
1699 }
1702 gt_pointer_operator new_value;
1706 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
1708 static int
1710 {
1723 }
1725 /* This routine compares two fields like method_name_cmp but using the
1726 pointer operator in resort_field_decl_data. */
1728 static int
1730 {
1739 {
1746 }
1748 }
1750 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
1752 void
1755 gt_pointer_operator new_value,
1757 {
1761 tree fn;
1763 /* The type conversion ops have to live at the front of the vec, so we
1764 can't sort them. */
1772 {
1776 resort_method_name_cmp);
1777 }
1778 }
1780 /* Warn about duplicate methods in fn_fields.
1782 Sort methods that are not special (i.e., constructors, destructors,
1783 and type conversion operators) so that we can find them faster in
1784 search. */
1786 static void
1788 {
1789 tree fn_fields;
1799 /* Clear DECL_IN_AGGR_P for all functions. */
1804 /* Issue warnings about private constructors and such. If there are
1805 no methods, then some public defaults are generated. */
1808 /* The type conversion ops have to live at the front of the vec, so we
1809 can't sort them. */
1818 }
1820 /* Make BINFO's vtable have N entries, including RTTI entries,
1821 vbase and vcall offsets, etc. Set its type and call the back end
1822 to lay it out. */
1824 static void
1826 {
1827 tree atype;
1828 tree vtable;
1834 /* We may have to grow the vtable. */
1837 {
1841 }
1842 }
1844 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
1845 have the same signature. */
1847 int
1849 {
1850 /* One destructor overrides another if they are the same kind of
1851 destructor. */
1855 /* But a non-destructor never overrides a destructor, nor vice
1856 versa, nor do different kinds of destructors override
1857 one-another. For example, a complete object destructor does not
1858 override a deleting destructor. */
1867 {
1875 }
1877 }
1879 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
1880 subobject. */
1882 static bool
1884 {
1885 tree probe;
1888 {
1892 /* If we meet a virtual base, we can't follow the inheritance
1893 any more. See if the complete type of DERIVED contains
1894 such a virtual base. */
1897 }
1899 }
1902 /* The function for which we are trying to find a final overrider. */
1903 tree fn;
1904 /* The base class in which the function was declared. */
1905 tree declaring_base;
1906 /* The candidate overriders. */
1907 tree candidates;
1908 /* Path to most derived. */
1912 /* Add the overrider along the current path to FFOD->CANDIDATES.
1913 Returns true if an overrider was found; false otherwise. */
1915 static bool
1919 {
1920 tree method;
1922 /* If BINFO is not the most derived type, try a more derived class.
1923 A definition there will overrider a definition here. */
1925 {
1926 depth--;
1930 }
1934 {
1937 /* Remove any candidates overridden by this new function. */
1939 {
1940 /* If *CANDIDATE overrides METHOD, then METHOD
1941 cannot override anything else on the list. */
1944 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
1947 else
1949 }
1951 /* Add the new function. */
1954 }
1957 }
1959 /* Called from find_final_overrider via dfs_walk. */
1961 static tree
1963 {
1971 }
1973 static tree
1975 {
1980 }
1982 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
1983 FN and whose TREE_VALUE is the binfo for the base where the
1984 overriding occurs. BINFO (in the hierarchy dominated by the binfo
1985 DERIVED) is the base object in which FN is declared. */
1987 static tree
1989 {
1990 find_final_overrider_data ffod;
1992 /* Getting this right is a little tricky. This is valid:
1994 struct S { virtual void f (); };
1995 struct T { virtual void f (); };
1996 struct U : public S, public T { };
1998 even though calling `f' in `U' is ambiguous. But,
2000 struct R { virtual void f(); };
2001 struct S : virtual public R { virtual void f (); };
2002 struct T : virtual public R { virtual void f (); };
2003 struct U : public S, public T { };
2005 is not -- there's no way to decide whether to put `S::f' or
2006 `T::f' in the vtable for `R'.
2008 The solution is to look at all paths to BINFO. If we find
2009 different overriders along any two, then there is a problem. */
2013 /* Determine the depth of the hierarchy. */
2024 /* If there was no winner, issue an error message. */
2029 }
2031 /* Return the index of the vcall offset for FN when TYPE is used as a
2032 virtual base. */
2034 static tree
2036 {
2038 tree_pair_p p;
2046 /* There should always be an appropriate index. */
2048 }
2050 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2051 dominated by T. FN has been overridden in BINFO; VIRTUALS points to the
2052 corresponding position in the BINFO_VIRTUALS list. */
2054 static void
2057 {
2058 tree b;
2059 tree overrider;
2060 tree delta;
2061 tree virtual_base;
2062 tree first_defn;
2068 /* Find the nearest primary base (possibly binfo itself) which defines
2069 this function; this is the class the caller will convert to when
2070 calling FN through BINFO. */
2072 {
2077 /* The nearest definition is from a lost primary. */
2080 }
2083 /* Find the final overrider. */
2086 {
2089 }
2092 /* Check for adjusting covariant return types. */
2100 /* If the overrider is invalid, don't even try. */
2102 {
2103 /* If FN is a covariant thunk, we must figure out the adjustment
2104 to the final base FN was converting to. As OVERRIDER_TARGET might
2105 also be converting to the return type of FN, we have to
2106 combine the two conversions here. */
2113 {
2117 }
2118 else
2122 /* Find the equivalent binfo within the return type of the
2123 overriding function. We will want the vbase offset from
2124 there. */
2126 over_return);
2129 {
2130 /* There was no existing virtual thunk (which takes
2131 precedence). So find the binfo of the base function's
2132 return type within the overriding function's return type.
2133 We cannot call lookup base here, because we're inside a
2134 dfs_walk, and will therefore clobber the BINFO_MARKED
2135 flags. Fortunately we know the covariancy is valid (it
2136 has already been checked), so we can just iterate along
2137 the binfos, which have been chained in inheritance graph
2138 order. Of course it is lame that we have to repeat the
2139 search here anyway -- we should really be caching pieces
2140 of the vtable and avoiding this repeated work. */
2143 /* Find the base binfo within the overriding function's
2144 return type. We will always find a thunk_binfo, except
2145 when the covariancy is invalid (which we will have
2146 already diagnosed). */
2149 thunk_binfo;
2155 /* See if virtual inheritance is involved. */
2157 virtual_offset;
2164 {
2168 {
2169 /* We convert via virtual base. Adjust the fixed
2170 offset to be from there. */
2171 offset =
2175 }
2177 /* There was an existing fixed offset, this must be
2178 from the base just converted to, and the base the
2179 FN was thunking to. */
2181 else
2183 }
2184 }
2187 /* Replace the overriding function with a covariant thunk. We
2188 will emit the overriding function in its own slot as
2189 well. */
2192 }
2193 else
2197 /* Assume that we will produce a thunk that convert all the way to
2198 the final overrider, and not to an intermediate virtual base. */
2201 /* See if we can convert to an intermediate virtual base first, and then
2202 use the vcall offset located there to finish the conversion. */
2204 {
2205 /* If we find the final overrider, then we can stop
2206 walking. */
2211 /* If we find a virtual base, and we haven't yet found the
2212 overrider, then there is a virtual base between the
2213 declaring base (first_defn) and the final overrider. */
2215 {
2218 }
2219 }
2222 {
2223 /* The ABI specifies that a covariant thunk includes a mangling
2224 for a this pointer adjustment. This-adjusting thunks that
2225 override a function from a virtual base have a vcall
2226 adjustment. When the virtual base in question is a primary
2227 virtual base, we know the adjustments are zero, (and in the
2228 non-covariant case, we would not use the thunk).
2229 Unfortunately we didn't notice this could happen, when
2230 designing the ABI and so never mandated that such a covariant
2231 thunk should be emitted. Because we must use the ABI mandated
2232 name, we must continue searching from the binfo where we
2233 found the most recent definition of the function, towards the
2234 primary binfo which first introduced the function into the
2235 vtable. If that enters a virtual base, we must use a vcall
2236 this-adjusting thunk. Bleah! */
2245 /* Even if we find a virtual base, the correct delta is
2246 between the overrider and the binfo we're building a vtable
2247 for. */
2249 }
2251 /* Compute the constant adjustment to the `this' pointer. The
2252 `this' pointer, when this function is called, will point at BINFO
2253 (or one of its primary bases, which are at the same offset). */
2255 /* The `this' pointer needs to be adjusted from the declaration to
2256 the nearest virtual base. */
2261 /* If the nearest definition is in a lost primary, we don't need an
2262 entry in our vtable. Except possibly in a constructor vtable,
2263 if we happen to get our primary back. In that case, the offset
2264 will be zero, as it will be a primary base. */
2266 else
2267 /* The `this' pointer needs to be adjusted from pointing to
2268 BINFO to pointing at the base where the final overrider
2269 appears. */
2270 virtual_covariant:
2281 else
2283 }
2285 /* Called from modify_all_vtables via dfs_walk. */
2287 static tree
2289 {
2291 tree virtuals;
2292 tree old_virtuals;
2296 /* A base without a vtable needs no modification, and its bases
2297 are uninteresting. */
2302 /* Don't do the primary vtable, if it's new. */
2306 /* There's no need to modify the vtable for a non-virtual primary
2307 base; we're not going to use that vtable anyhow. We do still
2308 need to do this for virtual primary bases, as they could become
2309 non-primary in a construction vtable. */
2314 /* Now, go through each of the virtual functions in the virtual
2315 function table for BINFO. Find the final overrider, and update
2316 the BINFO_VIRTUALS list appropriately. */
2319 virtuals;
2323 binfo,
2328 }
2330 /* Update all of the primary and secondary vtables for T. Create new
2331 vtables as required, and initialize their RTTI information. Each
2332 of the functions in VIRTUALS is declared in T and may override a
2333 virtual function from a base class; find and modify the appropriate
2334 entries to point to the overriding functions. Returns a list, in
2335 declaration order, of the virtual functions that are declared in T,
2336 but do not appear in the primary base class vtable, and which
2337 should therefore be appended to the end of the vtable for T. */
2339 static tree
2341 {
2345 /* Update all of the vtables. */
2348 /* Add virtual functions not already in our primary vtable. These
2349 will be both those introduced by this class, and those overridden
2350 from secondary bases. It does not include virtuals merely
2351 inherited from secondary bases. */
2353 {
2358 {
2359 /* We don't need to adjust the `this' pointer when
2360 calling this function. */
2364 /* This is a function not already in our vtable. Keep it. */
2366 }
2367 else
2368 /* We've already got an entry for this function. Skip it. */
2370 }
2373 }
2375 /* Get the base virtual function declarations in T that have the
2376 indicated NAME. */
2378 static tree
2380 {
2381 tree methods;
2386 /* Find virtual functions in T with the indicated NAME. */
2390 methods;
2392 {
2398 }
2404 {
2407 base_fndecls);
2408 }
2411 }
2413 /* If this declaration supersedes the declaration of
2414 a method declared virtual in the base class, then
2415 mark this field as being virtual as well. */
2417 void
2419 {
2421 /* In [temp.mem] we have:
2423 A specialization of a member function template does not
2424 override a virtual function from a base class. */
2431 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
2432 the error_mark_node so that we know it is an overriding
2433 function. */
2437 {
2441 }
2442 }
2444 /* Warn about hidden virtual functions that are not overridden in t.
2445 We know that constructors and destructors don't apply. */
2447 static void
2449 {
2451 tree fns;
2454 /* We go through each separately named virtual function. */
2458 {
2459 tree fn;
2460 tree name;
2461 tree fndecl;
2462 tree base_fndecls;
2463 tree base_binfo;
2464 tree binfo;
2467 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
2468 have the same name. Figure out what name that is. */
2470 /* There are no possibly hidden functions yet. */
2472 /* Iterate through all of the base classes looking for possibly
2473 hidden functions. */
2476 {
2479 base_fndecls);
2480 }
2482 /* If there are no functions to hide, continue. */
2486 /* Remove any overridden functions. */
2488 {
2491 {
2495 /* If the method from the base class has the same
2496 signature as the method from the derived class, it
2497 has been overridden. */
2500 else
2502 }
2503 }
2505 /* Now give a warning for all base functions without overriders,
2506 as they are hidden. */
2508 {
2509 /* Here we know it is a hider, and no overrider exists. */
2513 }
2514 }
2515 }
2517 /* Check for things that are invalid. There are probably plenty of other
2518 things we should check for also. */
2520 static void
2522 {
2523 tree field;
2526 {
2534 {
2538 {
2539 /* We're generally only interested in entities the user
2540 declared, but we also find nested classes by noticing
2541 the TYPE_DECL that we create implicitly. You're
2542 allowed to put one anonymous union inside another,
2543 though, so we explicitly tolerate that. We use
2544 TYPE_ANONYMOUS_P rather than ANON_AGGR_TYPE_P so that
2545 we also allow unnamed types used for defining fields. */
2552 {
2556 else
2560 }
2563 {
2566 else
2568 }
2570 {
2573 else
2575 }
2579 }
2580 }
2581 }
2582 }
2584 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
2585 will be used later during class template instantiation.
2586 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
2587 a non-static member data (FIELD_DECL), a member function
2588 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
2589 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
2590 When FRIEND_P is nonzero, T is either a friend class
2591 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
2592 (FUNCTION_DECL, TEMPLATE_DECL). */
2594 void
2596 {
2597 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
2602 }
2604 /* Create default constructors, assignment operators, and so forth for
2605 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
2606 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
2607 the class cannot have a default constructor, copy constructor
2608 taking a const reference argument, or an assignment operator taking
2609 a const reference, respectively. */
2611 static void
2615 {
2616 /* Destructor. */
2618 {
2619 /* In general, we create destructors lazily. */
2621 /* However, if the implicit destructor is non-trivial
2622 destructor, we sometimes have to create it at this point. */
2624 {
2628 /* If this a Java class, any non-trivial destructor is
2629 invalid, even if compiler-generated. Therefore, if the
2630 destructor is non-trivial we create it now. */
2632 else
2633 {
2634 tree binfo;
2635 tree base_binfo;
2638 /* If the implicit destructor will be virtual, then we must
2639 generate it now because (unfortunately) we do not
2640 generate virtual tables lazily. */
2643 {
2644 tree base_type;
2645 tree dtor;
2650 {
2653 }
2654 }
2655 }
2657 /* If we can't get away with being lazy, generate the destructor
2658 now. */
2661 }
2662 }
2664 /* [class.ctor]
2666 If there is no user-declared constructor for a class, a default
2667 constructor is implicitly declared. */
2669 {
2672 }
2674 /* [class.ctor]
2676 If a class definition does not explicitly declare a copy
2677 constructor, one is declared implicitly. */
2679 {
2683 }
2685 /* Currently only lambdas get a lazy move ctor, but N2987 adds them for
2686 other classes. */
2690 /* If there is no assignment operator, one will be created if and
2691 when it is needed. For now, just record whether or not the type
2692 of the parameter to the assignment operator will be a const or
2693 non-const reference. */
2695 {
2699 }
2700 }
2702 /* Subroutine of finish_struct_1. Recursively count the number of fields
2703 in TYPE, including anonymous union members. */
2705 static int
2707 {
2708 tree x;
2711 {
2714 else
2716 }
2718 }
2720 /* Subroutine of finish_struct_1. Recursively add all the fields in the
2721 TREE_LIST FIELDS to the SORTED_FIELDS_TYPE elts, starting at offset IDX. */
2723 static int
2725 {
2726 tree x;
2728 {
2731 else
2733 }
2735 }
2737 /* FIELD is a bit-field. We are finishing the processing for its
2738 enclosing type. Issue any appropriate messages and set appropriate
2739 flags. Returns false if an error has been diagnosed. */
2741 static bool
2743 {
2745 tree w;
2747 /* Extract the declared width of the bitfield, which has been
2748 temporarily stashed in DECL_INITIAL. */
2751 /* Remove the bit-field width indicator so that the rest of the
2752 compiler does not treat that value as an initializer. */
2755 /* Detect invalid bit-field type. */
2757 {
2760 }
2761 else
2762 {
2763 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
2766 /* detect invalid field size. */
2770 {
2773 }
2775 {
2778 }
2780 {
2783 }
2792 }
2795 {
2799 }
2800 else
2801 {
2802 /* Non-bit-fields are aligned for their type. */
2806 }
2807 }
2809 /* FIELD is a non bit-field. We are finishing the processing for its
2810 enclosing type T. Issue any appropriate messages and set appropriate
2811 flags. */
2813 static void
2815 tree t,
2819 {
2822 /* An anonymous union cannot contain any fields which would change
2823 the settings of CANT_HAVE_CONST_CTOR and friends. */
2825 ;
2826 /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous
2827 structs. So, we recurse through their fields here. */
2829 {
2830 tree fields;
2836 }
2837 /* Check members with class type for constructors, destructors,
2838 etc. */
2840 {
2841 /* Never let anything with uninheritable virtuals
2842 make it through without complaint. */
2846 {
2849 field);
2854 field);
2855 }
2856 else
2857 {
2864 }
2871 }
2873 {
2874 /* `build_class_init_list' does not recognize
2875 non-FIELD_DECLs. */
2879 }
2880 }
2882 /* Check the data members (both static and non-static), class-scoped
2883 typedefs, etc., appearing in the declaration of T. Issue
2884 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
2885 declaration order) of access declarations; each TREE_VALUE in this
2886 list is a USING_DECL.
2888 In addition, set the following flags:
2890 EMPTY_P
2891 The class is empty, i.e., contains no non-static data members.
2893 CANT_HAVE_CONST_CTOR_P
2894 This class cannot have an implicitly generated copy constructor
2895 taking a const reference.
2897 CANT_HAVE_CONST_ASN_REF
2898 This class cannot have an implicitly generated assignment
2899 operator taking a const reference.
2901 All of these flags should be initialized before calling this
2902 function.
2904 Returns a pointer to the end of the TYPE_FIELDs chain; additional
2905 fields can be added by adding to this chain. */
2907 static void
2911 {
2919 /* Assume there are no access declarations. */
2921 /* Assume this class has no pointer members. */
2923 /* Assume none of the members of this class have default
2924 initializations. */
2928 {
2936 {
2937 /* Prune the access declaration from the list of fields. */
2940 /* Save the access declarations for our caller. */
2943 /* Since we've reset *FIELD there's no reason to skip to the
2944 next field. */
2947 }
2953 /* If we've gotten this far, it's a data member, possibly static,
2954 or an enumerator. */
2957 /* When this goes into scope, it will be a non-local reference. */
2961 {
2962 /* [class.union]
2964 If a union contains a static data member, or a member of
2965 reference type, the program is ill-formed. */
2967 {
2970 }
2972 {
2977 }
2978 }
2980 /* Perform error checking that did not get done in
2981 grokdeclarator. */
2983 {
2987 }
2989 {
2993 }
3001 /* Now it can only be a FIELD_DECL. */
3006 /* A standard-layout class is a class that:
3007 ...
3008 has the same access control (Clause 11) for all non-static data members,
3009 ... */
3016 /* If this is of reference type, check if it needs an init. */
3018 {
3024 /* ARM $12.6.2: [A member initializer list] (or, for an
3025 aggregate, initialization by a brace-enclosed list) is the
3026 only way to initialize nonstatic const and reference
3027 members. */
3029 }
3034 {
3036 {
3037 warning
3040 x);
3042 }
3046 }
3049 /* We don't treat zero-width bitfields as making a class
3050 non-empty. */
3051 ;
3052 else
3053 {
3054 /* The class is non-empty. */
3056 /* The class is not even nearly empty. */
3058 /* If one of the data members contains an empty class,
3059 so does T. */
3063 }
3065 /* This is used by -Weffc++ (see below). Warn only for pointers
3066 to members which might hold dynamic memory. So do not warn
3067 for pointers to functions or pointers to members. */
3074 {
3079 }
3085 /* DR 148 now allows pointers to members (which are POD themselves),
3086 to be allowed in POD structs. */
3095 /* If any field is const, the structure type is pseudo-const. */
3097 {
3102 /* ARM $12.6.2: [A member initializer list] (or, for an
3103 aggregate, initialization by a brace-enclosed list) is the
3104 only way to initialize nonstatic const and reference
3105 members. */
3107 }
3108 /* A field that is pseudo-const makes the structure likewise. */
3110 {
3115 }
3117 /* Core issue 80: A nonstatic data member is required to have a
3118 different name from the class iff the class has a
3119 user-declared constructor. */
3124 /* We set DECL_C_BIT_FIELD in grokbitfield.
3125 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3128 cant_have_const_ctor_p,
3129 no_const_asn_ref_p,
3131 }
3133 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3134 it should also define a copy constructor and an assignment operator to
3135 implement the correct copy semantic (deep vs shallow, etc.). As it is
3136 not feasible to check whether the constructors do allocate dynamic memory
3137 and store it within members, we approximate the warning like this:
3139 -- Warn only if there are members which are pointers
3140 -- Warn only if there is a non-trivial constructor (otherwise,
3141 there cannot be memory allocated).
3142 -- Warn only if there is a non-trivial destructor. We assume that the
3143 user at least implemented the cleanup correctly, and a destructor
3144 is needed to free dynamic memory.
3146 This seems enough for practical purposes. */
3148 && has_pointers
3152 {
3156 {
3161 }
3165 }
3167 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
3171 /* Check anonymous struct/anonymous union fields. */
3174 /* We've built up the list of access declarations in reverse order.
3175 Fix that now. */
3177 }
3179 /* If TYPE is an empty class type, records its OFFSET in the table of
3180 OFFSETS. */
3182 static int
3184 {
3185 splay_tree_node n;
3190 /* Record the location of this empty object in OFFSETS. */
3198 type,
3202 }
3204 /* Returns nonzero if TYPE is an empty class type and there is
3205 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
3207 static int
3209 {
3210 splay_tree_node n;
3211 tree t;
3216 /* Record the location of this empty object in OFFSETS. */
3226 }
3228 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
3229 F for every subobject, passing it the type, offset, and table of
3230 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
3231 be traversed.
3233 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
3234 than MAX_OFFSET will not be walked.
3236 If F returns a nonzero value, the traversal ceases, and that value
3237 is returned. Otherwise, returns zero. */
3239 static int
3241 subobject_offset_fn f,
3242 tree offset,
3243 splay_tree offsets,
3244 tree max_offset,
3246 {
3250 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
3251 stop. */
3259 {
3263 }
3266 {
3267 tree field;
3268 tree binfo;
3271 /* Avoid recursing into objects that are not interesting. */
3275 /* Record the location of TYPE. */
3280 /* Iterate through the direct base classes of TYPE. */
3284 {
3285 tree binfo_offset;
3298 offset,
3300 else
3301 {
3302 tree orig_binfo;
3303 /* We cannot rely on BINFO_OFFSET being set for the base
3304 class yet, but the offsets for direct non-virtual
3305 bases can be calculated by going back to the TYPE. */
3308 offset,
3310 }
3313 f,
3314 binfo_offset,
3315 offsets,
3316 max_offset,
3321 }
3324 {
3328 /* Iterate through the virtual base classes of TYPE. In G++
3329 3.2, we included virtual bases in the direct base class
3330 loop above, which results in incorrect results; the
3331 correct offsets for virtual bases are only known when
3332 working with the most derived type. */
3336 {
3338 f,
3340 offset,
3342 offsets,
3343 max_offset,
3347 }
3348 else
3349 {
3350 /* We still have to walk the primary base, if it is
3351 virtual. (If it is non-virtual, then it was walked
3352 above.) */
3358 {
3359 r = (walk_subobject_offsets
3364 }
3365 }
3366 }
3368 /* Iterate through the fields of TYPE. */
3371 {
3372 tree field_offset;
3376 else
3377 /* In G++ 3.2, DECL_FIELD_OFFSET was used. */
3381 f,
3383 offset,
3384 field_offset),
3385 offsets,
3386 max_offset,
3390 }
3391 }
3393 {
3396 tree index;
3398 /* Avoid recursing into objects that are not interesting. */
3403 /* Step through each of the elements in the array. */
3405 /* G++ 3.2 had an off-by-one error here. */
3410 {
3412 f,
3413 offset,
3414 offsets,
3415 max_offset,
3421 /* If this new OFFSET is bigger than the MAX_OFFSET, then
3422 there's no point in iterating through the remaining
3423 elements of the array. */
3426 }
3427 }
3430 }
3432 /* Record all of the empty subobjects of TYPE (either a type or a
3433 binfo). If IS_DATA_MEMBER is true, then a non-static data member
3434 is being placed at OFFSET; otherwise, it is a base class that is
3435 being placed at OFFSET. */
3437 static void
3439 tree offset,
3440 splay_tree offsets,
3442 {
3443 tree max_offset;
3444 /* If recording subobjects for a non-static data member or a
3445 non-empty base class , we do not need to record offsets beyond
3446 the size of the biggest empty class. Additional data members
3447 will go at the end of the class. Additional base classes will go
3448 either at offset zero (if empty, in which case they cannot
3449 overlap with offsets past the size of the biggest empty class) or
3450 at the end of the class.
3452 However, if we are placing an empty base class, then we must record
3453 all offsets, as either the empty class is at offset zero (where
3454 other empty classes might later be placed) or at the end of the
3455 class (where other objects might then be placed, so other empty
3456 subobjects might later overlap). */
3460 else
3464 }
3466 /* Returns nonzero if any of the empty subobjects of TYPE (located at
3467 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
3468 virtual bases of TYPE are examined. */
3470 static int
3472 tree offset,
3473 splay_tree offsets,
3475 {
3476 splay_tree_node max_node;
3478 /* Get the node in OFFSETS that indicates the maximum offset where
3479 an empty subobject is located. */
3481 /* If there aren't any empty subobjects, then there's no point in
3482 performing this check. */
3488 vbases_p);
3489 }
3491 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
3492 non-static data member of the type indicated by RLI. BINFO is the
3493 binfo corresponding to the base subobject, OFFSETS maps offsets to
3494 types already located at those offsets. This function determines
3495 the position of the DECL. */
3497 static void
3499 tree decl,
3500 tree binfo,
3501 splay_tree offsets)
3502 {
3505 tree type;
3508 {
3509 /* For the purposes of determining layout conflicts, we want to
3510 use the class type of BINFO; TREE_TYPE (DECL) will be the
3511 CLASSTYPE_AS_BASE version, which does not contain entries for
3512 zero-sized bases. */
3515 }
3516 else
3517 {
3520 }
3522 /* Try to place the field. It may take more than one try if we have
3523 a hard time placing the field without putting two objects of the
3524 same type at the same address. */
3526 {
3529 /* Place this field. */
3533 /* We have to check to see whether or not there is already
3534 something of the same type at the offset we're about to use.
3535 For example, consider:
3537 struct S {};
3538 struct T : public S { int i; };
3539 struct U : public S, public T {};
3541 Here, we put S at offset zero in U. Then, we can't put T at
3542 offset zero -- its S component would be at the same address
3543 as the S we already allocated. So, we have to skip ahead.
3544 Since all data members, including those whose type is an
3545 empty class, have nonzero size, any overlap can happen only
3546 with a direct or indirect base-class -- it can't happen with
3547 a data member. */
3548 /* In a union, overlap is permitted; all members are placed at
3549 offset zero. */
3552 /* G++ 3.2 did not check for overlaps when placing a non-empty
3553 virtual base. */
3558 {
3559 /* Strip off the size allocated to this field. That puts us
3560 at the first place we could have put the field with
3561 proper alignment. */
3564 /* Bump up by the alignment required for the type. */
3565 rli->bitpos
3571 }
3572 else
3573 /* There was no conflict. We're done laying out this field. */
3575 }
3577 /* Now that we know where it will be placed, update its
3578 BINFO_OFFSET. */
3580 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
3581 this point because their BINFO_OFFSET is copied from another
3582 hierarchy. Therefore, we may not need to add the entire
3583 OFFSET. */
3589 }
3591 /* Returns true if TYPE is empty and OFFSET is nonzero. */
3593 static int
3595 tree offset,
3596 splay_tree offsets ATTRIBUTE_UNUSED)
3597 {
3599 }
3601 /* Layout the empty base BINFO. EOC indicates the byte currently just
3602 past the end of the class, and should be correctly aligned for a
3603 class of the type indicated by BINFO; OFFSETS gives the offsets of
3604 the empty bases allocated so far. T is the most derived
3605 type. Return nonzero iff we added it at the end. */
3607 static bool
3610 {
3611 tree alignment;
3615 /* This routine should only be used for empty classes. */
3620 {
3622 propagate_binfo_offsets
3625 else
3627 "offset of empty base %qT may not be ABI-compliant and may"
3630 }
3632 /* This is an empty base class. We first try to put it at offset
3633 zero. */
3636 offsets,
3638 {
3639 /* That didn't work. Now, we move forward from the next
3640 available spot in the class. */
3644 {
3647 offsets,
3649 /* We finally found a spot where there's no overlap. */
3652 /* There's overlap here, too. Bump along to the next spot. */
3654 }
3655 }
3658 {
3663 }
3666 }
3668 /* Layout the base given by BINFO in the class indicated by RLI.
3669 *BASE_ALIGN is a running maximum of the alignments of
3670 any base class. OFFSETS gives the location of empty base
3671 subobjects. T is the most derived type. Return nonzero if the new
3672 object cannot be nearly-empty. A new FIELD_DECL is inserted at
3673 *NEXT_FIELD, unless BINFO is for an empty base class.
3675 Returns the location at which the next field should be inserted. */
3680 {
3685 /* This error is now reported in xref_tag, thus giving better
3686 location information. */
3689 /* Place the base class. */
3691 {
3692 tree decl;
3694 /* The containing class is non-empty because it has a non-empty
3695 base class. */
3698 /* Create the FIELD_DECL. */
3705 {
3713 /* Try to place the field. It may take more than one try if we
3714 have a hard time placing the field without putting two
3715 objects of the same type at the same address. */
3717 /* Add the new FIELD_DECL to the list of fields for T. */
3721 }
3722 }
3723 else
3724 {
3725 tree eoc;
3728 /* On some platforms (ARM), even empty classes will not be
3729 byte-aligned. */
3734 /* A nearly-empty class "has no proper base class that is empty,
3735 not morally virtual, and at an offset other than zero." */
3737 {
3740 /* The check above (used in G++ 3.2) is insufficient because
3741 an empty class placed at offset zero might itself have an
3742 empty base at a nonzero offset. */
3744 empty_base_at_nonzero_offset_p,
3745 size_zero_node,
3749 {
3752 else
3754 "class %qT will be considered nearly empty in a "
3756 }
3757 }
3759 /* We do not create a FIELD_DECL for empty base classes because
3760 it might overlap some other field. We want to be able to
3761 create CONSTRUCTORs for the class by iterating over the
3762 FIELD_DECLs, and the back end does not handle overlapping
3763 FIELD_DECLs. */
3765 /* An empty virtual base causes a class to be non-empty
3766 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
3767 here because that was already done when the virtual table
3768 pointer was created. */
3769 }
3771 /* Record the offsets of BINFO and its base subobjects. */
3774 offsets,
3778 }
3780 /* Layout all of the non-virtual base classes. Record empty
3781 subobjects in OFFSETS. T is the most derived type. Return nonzero
3782 if the type cannot be nearly empty. The fields created
3783 corresponding to the base classes will be inserted at
3784 *NEXT_FIELD. */
3786 static void
3789 {
3790 /* Chain to hold all the new FIELD_DECLs which stand in for base class
3791 subobjects. */
3796 /* The primary base class is always allocated first. */
3801 /* Now allocate the rest of the bases. */
3803 {
3804 tree base_binfo;
3808 /* The primary base was already allocated above, so we don't
3809 need to allocate it again here. */
3813 /* Virtual bases are added at the end (a primary virtual base
3814 will have already been added). */
3820 }
3821 }
3823 /* Go through the TYPE_METHODS of T issuing any appropriate
3824 diagnostics, figuring out which methods override which other
3825 methods, and so forth. */
3827 static void
3829 {
3830 tree x;
3833 {
3837 /* The name of the field is the original field name
3838 Save this in auxiliary field for later overloading. */
3840 {
3844 }
3845 /* All user-provided destructors are non-trivial. */
3848 }
3849 }
3851 /* FN is a constructor or destructor. Clone the declaration to create
3852 a specialized in-charge or not-in-charge version, as indicated by
3853 NAME. */
3855 static tree
3857 {
3858 tree parms;
3859 tree clone;
3861 /* Copy the function. */
3863 /* Reset the function name. */
3866 /* Remember where this function came from. */
3868 /* Make it easy to find the CLONE given the FN. */
3872 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
3874 {
3881 }
3884 /* There's no pending inline data for this function. */
3888 /* The base-class destructor is not virtual. */
3890 {
3894 }
3896 /* If there was an in-charge parameter, drop it from the function
3897 type. */
3899 {
3900 tree basetype;
3901 tree parmtypes;
3902 tree exceptions;
3907 /* Skip the `this' parameter. */
3909 /* Skip the in-charge parameter. */
3911 /* And the VTT parm, in a complete [cd]tor. */
3915 /* If this is subobject constructor or destructor, add the vtt
3916 parameter. */
3920 parmtypes);
3923 exceptions);
3927 }
3929 /* Copy the function parameters. */
3931 /* Remove the in-charge parameter. */
3933 {
3937 }
3938 /* And the VTT parm, in a complete [cd]tor. */
3940 {
3943 else
3944 {
3948 }
3949 }
3952 {
3955 }
3957 /* Create the RTL for this function. */
3965 }
3967 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
3968 not invoke this function directly.
3970 For a non-thunk function, returns the address of the slot for storing
3971 the function it is a clone of. Otherwise returns NULL_TREE.
3973 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
3974 cloned_function is unset. This is to support the separate
3975 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
3976 on a template makes sense, but not the former. */
3978 tree *
3980 {
3988 {
3989 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
3992 else
3993 #endif
3995 }
4000 else
4002 }
4004 /* Produce declarations for all appropriate clones of FN. If
4005 UPDATE_METHOD_VEC_P is nonzero, the clones are added to the
4006 CLASTYPE_METHOD_VEC as well. */
4008 void
4010 {
4011 tree clone;
4013 /* Avoid inappropriate cloning. */
4019 {
4020 /* For each constructor, we need two variants: an in-charge version
4021 and a not-in-charge version. */
4028 }
4029 else
4030 {
4033 /* For each destructor, we need three variants: an in-charge
4034 version, a not-in-charge version, and an in-charge deleting
4035 version. We clone the deleting version first because that
4036 means it will go second on the TYPE_METHODS list -- and that
4037 corresponds to the correct layout order in the virtual
4038 function table.
4040 For a non-virtual destructor, we do not build a deleting
4041 destructor. */
4043 {
4047 }
4054 }
4056 /* Note that this is an abstract function that is never emitted. */
4058 }
4060 /* DECL is an in charge constructor, which is being defined. This will
4061 have had an in class declaration, from whence clones were
4062 declared. An out-of-class definition can specify additional default
4063 arguments. As it is the clones that are involved in overload
4064 resolution, we must propagate the information from the DECL to its
4065 clones. */
4067 void
4069 {
4070 tree clone;
4074 {
4081 /* Skip the 'this' parameter. */
4097 {
4102 {
4103 /* A default parameter has been added. Adjust the
4104 clone's parameters. */
4108 tree type;
4113 {
4116 clone_parms);
4118 }
4121 clone_parms);
4130 }
4131 }
4133 }
4134 }
4136 /* For each of the constructors and destructors in T, create an
4137 in-charge and not-in-charge variant. */
4139 static void
4141 {
4142 tree fns;
4144 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
4145 out now. */
4153 }
4155 /* Returns true iff class T has a user-defined constructor other than
4156 the default constructor. */
4158 bool
4160 {
4161 tree fns;
4167 {
4174 }
4177 }
4179 /* Returns the defaulted constructor if T has one. Otherwise, returns
4180 NULL_TREE. */
4182 tree
4184 {
4191 {
4195 {
4201 }
4202 }
4205 }
4207 /* Returns true iff FN is a user-provided function, i.e. user-declared
4208 and not defaulted at its first declaration; or explicit, private,
4209 protected, or non-const. */
4211 bool
4213 {
4216 else
4219 }
4221 /* Returns true iff class T has a user-provided constructor. */
4223 bool
4225 {
4226 tree fns;
4234 /* This can happen in error cases; avoid crashing. */
4243 }
4245 /* Returns true iff class T has a user-provided default constructor. */
4247 bool
4249 {
4256 {
4260 {
4266 }
4267 }
4270 }
4272 /* Remove all zero-width bit-fields from T. */
4274 static void
4276 {
4281 {
4284 /* We should not be confused by the fact that grokbitfield
4285 temporarily sets the width of the bit field into
4286 DECL_INITIAL (*fieldsp).
4287 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
4288 to that width. */
4291 else
4293 }
4294 }
4296 /* Returns TRUE iff we need a cookie when dynamically allocating an
4297 array whose elements have the indicated class TYPE. */
4299 static bool
4301 {
4302 tree fns;
4307 /* If there's a non-trivial destructor, we need a cookie. In order
4308 to iterate through the array calling the destructor for each
4309 element, we'll have to know how many elements there are. */
4313 /* If the usual deallocation function is a two-argument whose second
4314 argument is of type `size_t', then we have to pass the size of
4315 the array to the deallocation function, so we will need to store
4316 a cookie. */
4320 /* If there are no `operator []' members, or the lookup is
4321 ambiguous, then we don't need a cookie. */
4324 /* Loop through all of the functions. */
4326 {
4327 tree fn;
4328 tree second_parm;
4330 /* Select the current function. */
4332 /* See if this function is a one-argument delete function. If
4333 it is, then it will be the usual deallocation function. */
4337 /* Do not consider this function if its second argument is an
4338 ellipsis. */
4341 /* Otherwise, if we have a two-argument function and the second
4342 argument is `size_t', it will be the usual deallocation
4343 function -- unless there is one-argument function, too. */
4347 }
4350 }
4352 /* Check the validity of the bases and members declared in T. Add any
4353 implicitly-generated functions (like copy-constructors and
4354 assignment operators). Compute various flag bits (like
4355 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
4356 level: i.e., independently of the ABI in use. */
4358 static void
4360 {
4361 /* Nonzero if the implicitly generated copy constructor should take
4362 a non-const reference argument. */
4364 /* Nonzero if the implicitly generated assignment operator
4365 should take a non-const reference argument. */
4367 tree access_decls;
4370 tree fn;
4372 /* By default, we use const reference arguments and generate default
4373 constructors. */
4377 /* Check all the base-classes. */
4381 /* Check all the method declarations. */
4384 /* Save the initial values of these flags which only indicate whether
4385 or not the class has user-provided functions. As we analyze the
4386 bases and members we can set these flags for other reasons. */
4390 /* Check all the data member declarations. We cannot call
4391 check_field_decls until we have called check_bases check_methods,
4392 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
4393 being set appropriately. */
4398 /* A nearly-empty class has to be vptr-containing; a nearly empty
4399 class contains just a vptr. */
4403 /* Do some bookkeeping that will guide the generation of implicitly
4404 declared member functions. */
4406 /* We need to call a constructor for this class if it has a
4407 user-provided constructor, or if the default constructor is going
4408 to initialize the vptr. (This is not an if-and-only-if;
4409 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
4410 themselves need constructing.) */
4413 /* [dcl.init.aggr]
4415 An aggregate is an array or a class with no user-provided
4416 constructors ... and no virtual functions.
4418 Again, other conditions for being an aggregate are checked
4419 elsewhere. */
4422 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
4423 retain the old definition internally for ABI reasons. */
4431 /* If the class has no user-declared constructor, but does have
4432 non-static const or reference data members that can never be
4433 initialized, issue a warning. */
4435 /* Classes with user-declared constructors are presumed to
4436 initialize these members. */
4438 /* Aggregates can be initialized with brace-enclosed
4439 initializers. */
4441 {
4442 tree field;
4445 {
4446 tree type;
4460 }
4461 }
4463 /* Synthesize any needed methods. */
4465 cant_have_const_ctor,
4466 no_const_asn_ref);
4468 /* Check defaulted declarations here so we have cant_have_const_ctor
4469 and don't need to worry about clones. */
4472 {
4475 {
4476 bool imp_const_p
4482 /* If the function is defaulted outside the class, we just
4483 give the synthesis error. */
4489 }
4491 }
4494 {
4495 /* "The closure type associated with a lambda-expression has a deleted
4496 default constructor and a deleted copy assignment operator." */
4503 /* "This class type is not an aggregate." */
4505 }
4507 /* Create the in-charge and not-in-charge variants of constructors
4508 and destructors. */
4511 /* Process the using-declarations. */
4515 /* Build and sort the CLASSTYPE_METHOD_VEC. */
4518 /* Figure out whether or not we will need a cookie when dynamically
4519 allocating an array of this type. */
4522 }
4524 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
4525 accordingly. If a new vfield was created (because T doesn't have a
4526 primary base class), then the newly created field is returned. It
4527 is not added to the TYPE_FIELDS list; it is the caller's
4528 responsibility to do that. Accumulate declared virtual functions
4529 on VIRTUALS_P. */
4531 static tree
4533 {
4534 tree fn;
4536 /* Collect the virtual functions declared in T. */
4540 {
4549 }
4551 /* If we couldn't find an appropriate base class, create a new field
4552 here. Even if there weren't any new virtual functions, we might need a
4553 new virtual function table if we're supposed to include vptrs in
4554 all classes that need them. */
4556 {
4557 /* We build this decl with vtbl_ptr_type_node, which is a
4558 `vtable_entry_type*'. It might seem more precise to use
4559 `vtable_entry_type (*)[N]' where N is the number of virtual
4560 functions. However, that would require the vtable pointer in
4561 base classes to have a different type than the vtable pointer
4562 in derived classes. We could make that happen, but that
4563 still wouldn't solve all the problems. In particular, the
4564 type-based alias analysis code would decide that assignments
4565 to the base class vtable pointer can't alias assignments to
4566 the derived class vtable pointer, since they have different
4567 types. Thus, in a derived class destructor, where the base
4568 class constructor was inlined, we could generate bad code for
4569 setting up the vtable pointer.
4571 Therefore, we use one type for all vtable pointers. We still
4572 use a type-correct type; it's just doesn't indicate the array
4573 bounds. That's better than using `void*' or some such; it's
4574 cleaner, and it let's the alias analysis code know that these
4575 stores cannot alias stores to void*! */
4576 tree field;
4589 /* This class is non-empty. */
4593 }
4596 }
4598 /* Add OFFSET to all base types of BINFO which is a base in the
4599 hierarchy dominated by T.
4601 OFFSET, which is a type offset, is number of bytes. */
4603 static void
4605 {
4607 tree primary_binfo;
4608 tree base_binfo;
4610 /* Update BINFO's offset. */
4615 offset));
4617 /* Find the primary base class. */
4623 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
4624 downwards. */
4626 {
4627 /* Don't do the primary base twice. */
4635 }
4636 }
4638 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
4639 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
4640 empty subobjects of T. */
4642 static void
4644 {
4645 tree vbase;
4654 {
4655 /* In G++ 3.2, we incorrectly rounded the size before laying out
4656 the virtual bases. */
4658 #ifdef STRUCTURE_SIZE_BOUNDARY
4659 /* Packed structures don't need to have minimum size. */
4662 #endif
4666 }
4668 /* Find the last field. The artificial fields created for virtual
4669 bases will go after the last extant field to date. */
4674 /* Go through the virtual bases, allocating space for each virtual
4675 base that is not already a primary base class. These are
4676 allocated in inheritance graph order. */
4678 {
4683 {
4686 /* This virtual base is not a primary base of any class in the
4687 hierarchy, so we have to add space for it. */
4691 /* If the first virtual base might have been placed at a
4692 lower address, had we started from CLASSTYPE_SIZE, rather
4693 than TYPE_SIZE, issue a warning. There can be both false
4694 positives and false negatives from this warning in rare
4695 cases; to deal with all the possibilities would probably
4696 require performing both layout algorithms and comparing
4697 the results which is not particularly tractable. */
4699 && first_vbase
4700 && (tree_int_cst_lt
4705 bitsize_unit_node),
4708 "offset of virtual base %qT is not ABI-compliant and "
4710 basetype);
4713 }
4714 }
4715 }
4717 /* Returns the offset of the byte just past the end of the base class
4718 BINFO. */
4720 static tree
4722 {
4723 tree size;
4728 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
4729 allocate some space for it. It cannot have virtual bases, so
4730 TYPE_SIZE_UNIT is fine. */
4732 else
4736 }
4738 /* Returns the offset of the byte just past the end of the base class
4739 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
4740 only non-virtual bases are included. */
4742 static tree
4744 {
4747 tree binfo;
4748 tree base_binfo;
4749 tree offset;
4754 {
4764 }
4766 /* G++ 3.2 did not check indirect virtual bases. */
4770 {
4774 }
4777 }
4779 /* Warn about bases of T that are inaccessible because they are
4780 ambiguous. For example:
4782 struct S {};
4783 struct T : public S {};
4784 struct U : public S, public T {};
4786 Here, `(S*) new U' is not allowed because there are two `S'
4787 subobjects of U. */
4789 static void
4791 {
4794 tree basetype;
4795 tree binfo;
4796 tree base_binfo;
4798 /* If there are no repeated bases, nothing can be ambiguous. */
4802 /* Check direct bases. */
4805 {
4811 }
4813 /* Check for ambiguous virtual bases. */
4817 {
4823 }
4824 }
4826 /* Compare two INTEGER_CSTs K1 and K2. */
4828 static int
4830 {
4832 }
4834 /* Increase the size indicated in RLI to account for empty classes
4835 that are "off the end" of the class. */
4837 static void
4839 {
4840 tree eoc;
4841 tree rli_size;
4843 /* It might be the case that we grew the class to allocate a
4844 zero-sized base class. That won't be reflected in RLI, yet,
4845 because we are willing to overlay multiple bases at the same
4846 offset. However, now we need to make sure that RLI is big enough
4847 to reflect the entire class. */
4853 {
4855 /* In version 1 of the ABI, the size of a class that ends with
4856 a bitfield was not rounded up to a whole multiple of a
4857 byte. Because rli_size_unit_so_far returns only the number
4858 of fully allocated bytes, any extra bits were not included
4859 in the size. */
4861 else
4862 /* The size should have been rounded to a whole byte. */
4865 rli->bitpos
4874 }
4875 }
4877 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
4878 BINFO_OFFSETs for all of the base-classes. Position the vtable
4879 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
4881 static void
4883 {
4884 tree non_static_data_members;
4885 tree field;
4886 tree vptr;
4887 record_layout_info rli;
4888 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
4889 types that appear at that offset. */
4890 splay_tree empty_base_offsets;
4891 /* True if the last field layed out was a bit-field. */
4893 /* The location at which the next field should be inserted. */
4895 /* T, as a base class. */
4896 tree base_t;
4898 /* Keep track of the first non-static data member. */
4901 /* Start laying out the record. */
4904 /* Mark all the primary bases in the hierarchy. */
4907 /* Create a pointer to our virtual function table. */
4910 /* The vptr is always the first thing in the class. */
4912 {
4917 }
4918 else
4921 /* Build FIELD_DECLs for all of the non-virtual base-types. */
4926 /* Layout the non-static data members. */
4928 {
4929 tree type;
4930 tree padding;
4932 /* We still pass things that aren't non-static data members to
4933 the back end, in case it wants to do something with them. */
4935 {
4937 /* If the static data member has incomplete type, keep track
4938 of it so that it can be completed later. (The handling
4939 of pending statics in finish_record_layout is
4940 insufficient; consider:
4942 struct S1;
4943 struct S2 { static S1 s1; };
4945 At this point, finish_record_layout will be called, but
4946 S1 is still incomplete.) */
4948 {
4950 /* The visibility of static data members is determined
4951 at their point of declaration, not their point of
4952 definition. */
4954 }
4956 }
4964 /* If this field is a bit-field whose width is greater than its
4965 type, then there are some special rules for allocating
4966 it. */
4969 {
4971 tree integer_type;
4973 /* We must allocate the bits as if suitably aligned for the
4974 longest integer type that fits in this many bits. type
4975 of the field. Then, we are supposed to use the left over
4976 bits as additional padding. */
4982 /* ITK now indicates a type that is too large for the
4983 field. We have to back up by one to find the largest
4984 type that fits. */
4987 /* Figure out how much additional padding is required. GCC
4988 3.2 always created a padding field, even if it had zero
4989 width. */
4992 {
4994 /* In a union, the padding field must have the full width
4995 of the bit-field; all fields start at offset zero. */
4997 else
4998 {
5001 "ABI-compliant and may change in a future "
5003 t);
5006 }
5007 }
5008 #ifdef PCC_BITFIELD_TYPE_MATTERS
5009 /* An unnamed bitfield does not normally affect the
5010 alignment of the containing class on a target where
5011 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
5012 make any exceptions for unnamed bitfields when the
5013 bitfields are longer than their types. Therefore, we
5014 temporarily give the field a name. */
5016 {
5019 }
5020 #endif
5025 empty_base_offsets);
5028 /* Now that layout has been performed, set the size of the
5029 field to the size of its declared type; the rest of the
5030 field is effectively invisible. */
5032 /* We must also reset the DECL_MODE of the field. */
5037 /* Versions of G++ before G++ 3.4 did not reset the
5038 DECL_MODE. */
5040 "the offset of %qD may not be ABI-compliant and may "
5042 }
5043 else
5045 empty_base_offsets);
5047 /* Remember the location of any empty classes in FIELD. */
5051 empty_base_offsets,
5054 /* If a bit-field does not immediately follow another bit-field,
5055 and yet it starts in the middle of a byte, we have failed to
5056 comply with the ABI. */
5059 /* The TREE_NO_WARNING flag gets set by Objective-C when
5060 laying out an Objective-C class. The ObjC ABI differs
5061 from the C++ ABI, and so we do not want a warning
5062 here. */
5064 && !last_field_was_bitfield
5067 bitsize_unit_node)))
5071 /* G++ used to use DECL_FIELD_OFFSET as if it were the byte
5072 offset of the field. */
5079 "classes to be placed at different locations in a "
5082 /* The middle end uses the type of expressions to determine the
5083 possible range of expression values. In order to optimize
5084 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
5085 must be made aware of the width of "i", via its type.
5087 Because C++ does not have integer types of arbitrary width,
5088 we must (for the purposes of the front end) convert from the
5089 type assigned here to the declared type of the bitfield
5090 whenever a bitfield expression is used as an rvalue.
5091 Similarly, when assigning a value to a bitfield, the value
5092 must be converted to the type given the bitfield here. */
5094 {
5099 {
5106 }
5107 }
5109 /* If we needed additional padding after this field, add it
5110 now. */
5112 {
5113 tree padding_field;
5116 FIELD_DECL,
5117 NULL_TREE,
5118 char_type_node);
5125 NULL_TREE,
5126 empty_base_offsets);
5127 }
5130 }
5133 {
5134 /* Make sure that we are on a byte boundary so that the size of
5135 the class without virtual bases will always be a round number
5136 of bytes. */
5139 }
5141 /* G++ 3.2 does not allow virtual bases to be overlaid with tail
5142 padding. */
5146 /* Delete all zero-width bit-fields from the list of fields. Now
5147 that the type is laid out they are no longer important. */
5150 /* Create the version of T used for virtual bases. We do not use
5151 make_class_type for this version; this is an artificial type. For
5152 a POD type, we just reuse T. */
5154 {
5157 /* Set the size and alignment for the new type. In G++ 3.2, all
5158 empty classes were considered to have size zero when used as
5159 base classes. */
5161 {
5166 "layout of classes derived from empty class %qT "
5168 t);
5169 }
5170 else
5171 {
5172 tree eoc;
5174 /* If the ABI version is not at least two, and the last
5175 field was a bit-field, RLI may not be on a byte
5176 boundary. In particular, rli_size_unit_so_far might
5177 indicate the last complete byte, while rli_size_so_far
5178 indicates the total number of bits used. Therefore,
5179 rli_size_so_far, rather than rli_size_unit_so_far, is
5180 used to compute TYPE_SIZE_UNIT. */
5188 eoc);
5195 }
5199 /* Copy the fields from T. */
5203 {
5205 FIELD_DECL,
5215 }
5217 /* Record the base version of the type. */
5220 }
5221 else
5224 /* Every empty class contains an empty class. */
5228 /* Set the TYPE_DECL for this type to contain the right
5229 value for DECL_OFFSET, so that we can use it as part
5230 of a COMPONENT_REF for multiple inheritance. */
5233 /* Now fix up any virtual base class types that we left lying
5234 around. We must get these done before we try to lay out the
5235 virtual function table. As a side-effect, this will remove the
5236 base subobject fields. */
5239 /* Make sure that empty classes are reflected in RLI at this
5240 point. */
5243 /* Make sure not to create any structures with zero size. */
5249 /* If this is a non-POD, declaring it packed makes a difference to how it
5250 can be used as a field; don't let finalize_record_size undo it. */
5254 /* Let the back end lay out the type. */
5257 /* Warn about bases that can't be talked about due to ambiguity. */
5260 /* Now that we're done with layout, give the base fields the real types. */
5265 /* Clean up. */
5272 }
5274 /* Determine the "key method" for the class type indicated by TYPE,
5275 and set CLASSTYPE_KEY_METHOD accordingly. */
5277 void
5279 {
5280 tree method;
5283 || processing_template_decl
5288 /* The key method is the first non-pure virtual function that is not
5289 inline at the point of class definition. On some targets the
5290 key function may not be inline; those targets should not call
5291 this function until the end of the translation unit. */
5297 {
5300 }
5303 }
5305 /* Perform processing required when the definition of T (a class type)
5306 is complete. */
5308 void
5310 {
5311 tree x;
5312 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
5317 {
5322 }
5324 /* If this type was previously laid out as a forward reference,
5325 make sure we lay it out again. */
5329 /* Make assumptions about the class; we'll reset the flags if
5330 necessary. */
5335 /* Do end-of-class semantic processing: checking the validity of the
5336 bases and members and add implicitly generated methods. */
5339 /* Find the key method. */
5341 {
5342 /* The Itanium C++ ABI permits the key method to be chosen when
5343 the class is defined -- even though the key method so
5344 selected may later turn out to be an inline function. On
5345 some systems (such as ARM Symbian OS) the key method cannot
5346 be determined until the end of the translation unit. On such
5347 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
5348 will cause the class to be added to KEYED_CLASSES. Then, in
5349 finish_file we will determine the key method. */
5353 /* If a polymorphic class has no key method, we may emit the vtable
5354 in every translation unit where the class definition appears. */
5357 }
5359 /* Layout the class itself. */
5362 /* We use the base type for trivial assignments, and hence it
5363 needs a mode. */
5368 /* If necessary, create the primary vtable for this class. */
5370 {
5371 /* We must enter these virtuals into the table. */
5375 /* Here we know enough to change the type of our virtual
5376 function table, but we will wait until later this function. */
5378 }
5381 {
5383 tree fn;
5390 /* Add entries for virtual functions introduced by this class. */
5394 /* Set DECL_VINDEX for all functions declared in this class. */
5396 fn;
5398 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
5400 {
5404 /* A thunk. We should never be calling this entry directly
5405 from this vtable -- we'd use the entry for the non
5406 thunk base function. */
5410 }
5411 }
5415 /* Complete the rtl for any static member objects of the type we're
5416 working on. */
5423 /* Done with FIELDS...now decide whether to sort these for
5424 faster lookups later.
5426 We use a small number because most searches fail (succeeding
5427 ultimately as the search bores through the inheritance
5428 hierarchy), and we want this failure to occur quickly. */
5432 {
5439 field_decl_cmp);
5441 }
5443 /* Complain if one of the field types requires lower visibility. */
5446 /* Make the rtl for any new vtables we have created, and unmark
5447 the base types we marked. */
5450 /* Build the VTT for T. */
5453 /* This warning does not make sense for Java classes, since they
5454 cannot have destructors. */
5456 {
5457 tree dtor;
5461 if it were virtual, we would have created it by now. */
5462 !dtor
5471 "%q#T has virtual functions and accessible"
5473 }
5480 /* Class layout, assignment of virtual table slots, etc., is now
5481 complete. Give the back end a chance to tweak the visibility of
5482 the class or perform any other required target modifications. */
5489 /* Finish debugging output for this type. */
5491 }
5493 /* When T was built up, the member declarations were added in reverse
5494 order. Rearrange them to declaration order. */
5496 void
5498 {
5499 tree next;
5500 tree prev;
5501 tree x;
5503 /* The following lists are all in reverse order. Put them in
5504 declaration order now. */
5508 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
5509 reverse order, so we can't just use nreverse. */
5514 {
5518 }
5520 {
5524 }
5525 }
5527 tree
5529 {
5532 /* Now that we've got all the field declarations, reverse everything
5533 as necessary. */
5538 /* Nadger the current location so that diagnostics point to the start of
5539 the struct, not the end. */
5543 {
5544 tree x;
5550 /* We need to emit an error message if this type was used as a parameter
5551 and it is an abstract type, even if it is a template. We construct
5552 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
5553 account and we call complete_vars with this type, which will check
5554 the PARM_DECLS. Note that while the type is being defined,
5555 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
5556 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
5563 /* Remember current #pragma pack value. */
5565 }
5566 else
5575 else
5582 }
5583 \f
5584 /* Return the dynamic type of INSTANCE, if known.
5585 Used to determine whether the virtual function table is needed
5586 or not.
5588 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5589 of our knowledge of its type. *NONNULL should be initialized
5590 before this function is called. */
5592 static tree
5594 {
5595 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
5598 {
5602 else
5606 /* This is a call to a constructor, hence it's never zero. */
5608 {
5612 }
5616 /* This is a call to a constructor, hence it's never zero. */
5618 {
5622 }
5631 /* Propagate nonnull. */
5636 CASE_CONVERT:
5642 {
5643 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
5644 with a real object -- given &p->f, p can still be null. */
5646 /* ??? Probably should check DECL_WEAK here. */
5649 }
5653 /* If this component is really a base class reference, then the field
5654 itself isn't definitive. */
5663 {
5667 }
5668 /* fall through... */
5673 {
5677 }
5679 {
5683 /* if we're in a ctor or dtor, we know our type. */
5687 {
5691 }
5692 }
5694 {
5695 /* We only need one hash table because it is always left empty. */
5699 htab_hash_pointer,
5700 htab_eq_pointer,
5703 /* Reference variables should be references to objects. */
5707 /* Enter the INSTANCE in a table to prevent recursion; a
5708 variable's initializer may refer to the variable
5709 itself. */
5713 {
5714 tree type;
5723 }
5724 }
5729 }
5730 #undef RECUR
5731 }
5733 /* Return nonzero if the dynamic type of INSTANCE is known, and
5734 equivalent to the static type. We also handle the case where
5735 INSTANCE is really a pointer. Return negative if this is a
5736 ctor/dtor. There the dynamic type is known, but this might not be
5737 the most derived base of the original object, and hence virtual
5738 bases may not be layed out according to this type.
5740 Used to determine whether the virtual function table is needed
5741 or not.
5743 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
5744 of our knowledge of its type. *NONNULL should be initialized
5745 before this function is called. */
5747 int
5749 {
5760 }
5762 \f
5763 void
5765 {
5768 current_class_stack
5776 }
5778 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
5780 static void
5782 {
5783 tree type;
5785 /* We are re-entering the same class we just left, so we don't
5786 have to search the whole inheritance matrix to find all the
5787 decls to bind again. Instead, we install the cached
5788 class_shadowed list and walk through it binding names. */
5791 /* Restore IDENTIFIER_TYPE_VALUE. */
5793 type;
5796 }
5798 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
5799 appropriate for TYPE.
5801 So that we may avoid calls to lookup_name, we cache the _TYPE
5802 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
5804 For multiple inheritance, we perform a two-pass depth-first search
5805 of the type lattice. */
5807 void
5809 {
5810 class_stack_node_t csn;
5814 /* Make sure there is enough room for the new entry on the stack. */
5816 {
5818 current_class_stack
5820 current_class_stack_size);
5821 }
5823 /* Insert a new entry on the class stack. */
5830 current_class_depth++;
5832 /* Now set up the new type. */
5838 /* By default, things in classes are private, while things in
5839 structures or unions are public. */
5841 ? access_private_node
5847 {
5848 /* Forcibly remove any old class remnants. */
5850 }
5856 else
5858 }
5860 /* When we exit a toplevel class scope, we save its binding level so
5861 that we can restore it quickly. Here, we've entered some other
5862 class, so we must invalidate our cache. */
5864 void
5866 {
5868 }
5870 /* Get out of the current class scope. If we were in a class scope
5871 previously, that is the one popped to. */
5873 void
5875 {
5878 current_class_depth--;
5884 }
5886 /* Mark the top of the class stack as hidden. */
5888 void
5890 {
5893 }
5895 /* Mark the top of the class stack as un-hidden. */
5897 void
5899 {
5902 }
5904 /* Returns 1 if the class type currently being defined is either T or
5905 a nested type of T. */
5907 bool
5909 {
5917 /* We start looking from 1 because entry 0 is from global scope,
5918 and has no type. */
5920 {
5921 tree c;
5924 else
5925 {
5929 }
5934 }
5936 }
5938 /* If either current_class_type or one of its enclosing classes are derived
5939 from T, return the appropriate type. Used to determine how we found
5940 something via unqualified lookup. */
5942 tree
5944 {
5947 /* The bases of a dependent type are unknown. */
5958 {
5963 }
5966 }
5968 /* Returns the innermost class type which is not a lambda closure type. */
5970 tree
5972 {
5975 /* We start looking from 1 because entry 0 is from global scope,
5976 and has no type. */
5978 {
5979 tree c;
5982 else
5983 {
5987 }
5992 }
5994 }
5996 /* When entering a class scope, all enclosing class scopes' names with
5997 static meaning (static variables, static functions, types and
5998 enumerators) have to be visible. This recursive function calls
5999 pushclass for all enclosing class contexts until global or a local
6000 scope is reached. TYPE is the enclosed class. */
6002 void
6004 {
6005 /* A namespace might be passed in error cases, like A::B:C. */
6013 }
6015 /* Undoes a push_nested_class call. */
6017 void
6019 {
6025 }
6027 /* Returns the number of extern "LANG" blocks we are nested within. */
6029 int
6031 {
6033 }
6035 /* Set global variables CURRENT_LANG_NAME to appropriate value
6036 so that behavior of name-mangling machinery is correct. */
6038 void
6040 {
6044 {
6046 }
6048 {
6050 /* DECL_IGNORED_P is initially set for these types, to avoid clutter.
6051 (See record_builtin_java_type in decl.c.) However, that causes
6052 incorrect debug entries if these types are actually used.
6053 So we re-enable debug output after extern "Java". */
6062 }
6064 {
6066 }
6067 else
6069 }
6071 /* Get out of the current language scope. */
6073 void
6075 {
6077 }
6078 \f
6079 /* Type instantiation routines. */
6081 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
6082 matches the TARGET_TYPE. If there is no satisfactory match, return
6083 error_mark_node, and issue an error & warning messages under
6084 control of FLAGS. Permit pointers to member function if FLAGS
6085 permits. If TEMPLATE_ONLY, the name of the overloaded function was
6086 a template-id, and EXPLICIT_TARGS are the explicitly provided
6087 template arguments.
6089 If OVERLOAD is for one or more member functions, then ACCESS_PATH
6090 is the base path used to reference those member functions. If
6091 TF_NO_ACCESS_CONTROL is not set in FLAGS, and the address is
6092 resolved to a member function, access checks will be performed and
6093 errors issued if appropriate. */
6095 static tree
6097 tree overload,
6098 tsubst_flags_t flags,
6100 tree explicit_targs,
6101 tree access_path)
6102 {
6103 /* Here's what the standard says:
6105 [over.over]
6107 If the name is a function template, template argument deduction
6108 is done, and if the argument deduction succeeds, the deduced
6109 arguments are used to generate a single template function, which
6110 is added to the set of overloaded functions considered.
6112 Non-member functions and static member functions match targets of
6113 type "pointer-to-function" or "reference-to-function." Nonstatic
6114 member functions match targets of type "pointer-to-member
6115 function;" the function type of the pointer to member is used to
6116 select the member function from the set of overloaded member
6117 functions. If a nonstatic member function is selected, the
6118 reference to the overloaded function name is required to have the
6119 form of a pointer to member as described in 5.3.1.
6121 If more than one function is selected, any template functions in
6122 the set are eliminated if the set also contains a non-template
6123 function, and any given template function is eliminated if the
6124 set contains a second template function that is more specialized
6125 than the first according to the partial ordering rules 14.5.5.2.
6126 After such eliminations, if any, there shall remain exactly one
6127 selected function. */
6130 /* We store the matches in a TREE_LIST rooted here. The functions
6131 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
6132 interoperability with most_specialized_instantiation. */
6134 tree fn;
6135 tree target_fn_type;
6137 /* By the time we get here, we should be seeing only real
6138 pointer-to-member types, not the internal POINTER_TYPE to
6139 METHOD_TYPE representation. */
6145 /* Check that the TARGET_TYPE is reasonable. */
6149 /* This is OK, too. */
6152 /* This is OK, too. This comes from a conversion to reference
6153 type. */
6155 else
6156 {
6162 }
6164 /* Non-member functions and static member functions match targets of type
6165 "pointer-to-function" or "reference-to-function." Nonstatic member
6166 functions match targets of type "pointer-to-member-function;" the
6167 function type of the pointer to member is used to select the member
6168 function from the set of overloaded member functions.
6170 So figure out the FUNCTION_TYPE that we want to match against. */
6173 /* If we can find a non-template function that matches, we can just
6174 use it. There's no point in generating template instantiations
6175 if we're just going to throw them out anyhow. But, of course, we
6176 can only do this when we don't *need* a template function. */
6178 {
6179 tree fns;
6182 {
6186 /* We're not looking for templates just yet. */
6191 /* We're looking for a non-static member, and this isn't
6192 one, or vice versa. */
6195 /* Ignore functions which haven't been explicitly
6196 declared. */
6200 /* See if there's a match. */
6203 }
6204 }
6206 /* Now, if we've already got a match (or matches), there's no need
6207 to proceed to the template functions. But, if we don't have a
6208 match we need to look at them, too. */
6210 {
6211 tree target_arg_types;
6212 tree target_ret_type;
6213 tree fns;
6216 tree arg;
6230 {
6232 tree instantiation;
6233 tree targs;
6236 /* We're only looking for templates. */
6241 /* We're not looking for a non-static member, and this is
6242 one, or vice versa. */
6245 /* Try to do argument deduction. */
6249 LOOKUP_NORMAL))
6250 /* Argument deduction failed. */
6253 /* Instantiate the template. */
6256 /* Instantiation failed. */
6259 /* See if there's a match. */
6262 }
6264 /* Now, remove all but the most specialized of the matches. */
6266 {
6271 NULL_TREE,
6272 NULL_TREE);
6273 }
6274 }
6276 /* Now we should have exactly one function in MATCHES. */
6278 {
6279 /* There were *no* matches. */
6281 {
6284 target_type);
6286 /* print_candidates expects a chain with the functions in
6287 TREE_VALUE slots, so we cons one up here (we're losing anyway,
6288 so why be clever?). */
6291 matches);
6294 }
6296 }
6298 {
6299 /* There were too many matches. First check if they're all
6300 the same function. */
6301 tree match;
6309 {
6311 {
6314 target_type);
6316 /* Since print_candidates expects the functions in the
6317 TREE_VALUE slot, we flip them here. */
6322 }
6325 }
6326 }
6328 /* Good, exactly one match. Now, convert it to the correct type. */
6333 {
6341 {
6344 }
6345 }
6347 /* If we're doing overload resolution purely for the purpose of
6348 determining conversion sequences, we should not consider the
6349 function used. If this conversion sequence is selected, the
6350 function will be marked as used at this point. */
6352 {
6353 /* Make =delete work with SFINAE. */
6358 }
6360 /* We could not check access to member functions when this
6361 expression was originally created since we did not know at that
6362 time to which function the expression referred. */
6365 {
6368 }
6372 else
6373 {
6374 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
6375 will mark the function as addressed, but here we must do it
6376 explicitly. */
6380 }
6381 }
6383 /* This function will instantiate the type of the expression given in
6384 RHS to match the type of LHSTYPE. If errors exist, then return
6385 error_mark_node. FLAGS is a bit mask. If TF_ERROR is set, then
6386 we complain on errors. If we are not complaining, never modify rhs,
6387 as overload resolution wants to try many possible instantiations, in
6388 the hope that at least one will work.
6390 For non-recursive calls, LHSTYPE should be a function, pointer to
6391 function, or a pointer to member function. */
6393 tree
6395 {
6402 {
6406 }
6409 {
6415 /* Microsoft allows `A::f' to be resolved to a
6416 pointer-to-member. */
6417 ;
6418 else
6419 {
6424 }
6425 }
6428 {
6431 }
6433 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
6434 deduce any type information. */
6436 {
6440 }
6442 /* There only a few kinds of expressions that may have a type
6443 dependent on overload resolution. */
6449 /* This should really only be used when attempting to distinguish
6450 what sort of a pointer to function we have. For now, any
6451 arithmetic operation which is not supported on pointers
6452 is rejected as an error. */
6455 {
6457 {
6463 /* Do not lose object's side effects. */
6467 }
6474 /* This can happen if we are forming a pointer-to-member for a
6475 member template. */
6478 /* Fall through. */
6481 {
6485 return
6489 }
6493 return
6497 access_path);
6500 {
6505 }
6512 }
6514 }
6515 \f
6516 /* Return the name of the virtual function pointer field
6517 (as an IDENTIFIER_NODE) for the given TYPE. Note that
6518 this may have to look back through base types to find the
6519 ultimate field name. (For single inheritance, these could
6520 all be the same name. Who knows for multiple inheritance). */
6522 static tree
6524 {
6531 {
6537 }
6545 }
6547 void
6549 {
6550 #ifdef GATHER_STATISTICS
6554 {
6559 }
6560 #endif
6561 }
6563 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
6564 according to [class]:
6565 The class-name is also inserted
6566 into the scope of the class itself. For purposes of access checking,
6567 the inserted class name is treated as if it were a public member name. */
6569 void
6571 {
6574 tree saved_cas;
6589 }
6591 /* Returns 1 if TYPE contains only padding bytes. */
6593 int
6595 {
6602 /* In G++ 3.2, whether or not a class was empty was determined by
6603 looking at its size. */
6606 else
6608 }
6610 /* Returns true if TYPE contains an empty class. */
6612 static bool
6614 {
6618 {
6619 tree field;
6620 tree binfo;
6621 tree base_binfo;
6633 }
6637 }
6639 /* Returns true if TYPE contains no actual data, just various
6640 possible combinations of empty classes. */
6642 bool
6644 {
6648 {
6649 tree field;
6650 tree binfo;
6651 tree base_binfo;
6664 }
6668 }
6670 /* Note that NAME was looked up while the current class was being
6671 defined and that the result of that lookup was DECL. */
6673 void
6675 {
6676 splay_tree names_used;
6678 /* If we're not defining a class, there's nothing to do. */
6684 /* If there's already a binding for this NAME, then we don't have
6685 anything to worry about. */
6698 }
6700 /* Note that NAME was declared (as DECL) in the current class. Check
6701 to see that the declaration is valid. */
6703 void
6705 {
6706 splay_tree names_used;
6707 splay_tree_node n;
6709 /* Look to see if we ever used this name. */
6710 names_used
6717 {
6718 /* [basic.scope.class]
6720 A name N used in a class S shall refer to the same declaration
6721 in its context and when re-evaluated in the completed scope of
6722 S. */
6726 }
6727 }
6729 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
6730 Secondary vtables are merged with primary vtables; this function
6731 will return the VAR_DECL for the primary vtable. */
6733 tree
6735 {
6736 tree decl;
6740 {
6743 }
6747 }
6750 /* Returns the binfo for the primary base of BINFO. If the resulting
6751 BINFO is a virtual base, and it is inherited elsewhere in the
6752 hierarchy, then the returned binfo might not be the primary base of
6753 BINFO in the complete object. Check BINFO_PRIMARY_P or
6754 BINFO_LOST_PRIMARY_P to be sure. */
6756 static tree
6758 {
6759 tree primary_base;
6766 }
6768 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
6770 static int
6772 {
6776 }
6778 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
6779 INDENT should be zero when called from the top level; it is
6780 incremented recursively. IGO indicates the next expected BINFO in
6781 inheritance graph ordering. */
6783 static tree
6786 tree binfo,
6787 tree igo,
6789 {
6791 tree base_binfo;
6799 {
6802 }
6817 {
6821 TFF_PLAIN_IDENTIFIER),
6823 }
6825 {
6828 }
6833 {
6837 {
6841 TFF_PLAIN_IDENTIFIER));
6842 }
6844 {
6848 TFF_PLAIN_IDENTIFIER));
6849 }
6851 {
6855 TFF_PLAIN_IDENTIFIER));
6856 }
6858 {
6862 TFF_PLAIN_IDENTIFIER));
6863 }
6867 }
6873 }
6875 /* Dump the BINFO hierarchy for T. */
6877 static void
6879 {
6891 }
6893 /* Debug interface to hierarchy dumping. */
6895 void
6897 {
6899 }
6901 static void
6903 {
6908 {
6911 }
6912 }
6914 static void
6916 {
6917 tree value;
6919 HOST_WIDE_INT elt;
6927 TFF_PLAIN_IDENTIFIER));
6934 }
6936 static void
6938 {
6946 {
6953 {
6957 }
6961 }
6964 }
6966 static void
6968 {
6976 {
6981 }
6984 }
6986 /* Dump a function or thunk and its thunkees. */
6988 static void
6990 {
6993 tree thunks;
7001 {
7011 else
7017 }
7021 }
7023 /* Dump the thunks for FN. */
7025 void
7027 {
7029 }
7031 /* Virtual function table initialization. */
7033 /* Create all the necessary vtables for T and its base classes. */
7035 static void
7037 {
7038 tree list;
7039 tree vbase;
7041 /* We lay out the primary and secondary vtables in one contiguous
7042 vtable. The primary vtable is first, followed by the non-virtual
7043 secondary vtables in inheritance graph order. */
7048 /* Then come the virtual bases, also in inheritance graph order. */
7050 {
7054 }
7058 }
7060 /* Initialize the vtable for BINFO with the INITS. */
7062 static void
7064 {
7065 tree decl;
7071 }
7073 /* Build the VTT (virtual table table) for T.
7074 A class requires a VTT if it has virtual bases.
7076 This holds
7077 1 - primary virtual pointer for complete object T
7078 2 - secondary VTTs for each direct non-virtual base of T which requires a
7079 VTT
7080 3 - secondary virtual pointers for each direct or indirect base of T which
7081 has virtual bases or is reachable via a virtual path from T.
7082 4 - secondary VTTs for each direct or indirect virtual base of T.
7084 Secondary VTTs look like complete object VTTs without part 4. */
7086 static void
7088 {
7089 tree inits;
7090 tree type;
7091 tree vtt;
7092 tree index;
7094 /* Build up the initializers for the VTT. */
7099 /* If we didn't need a VTT, we're done. */
7103 /* Figure out the type of the VTT. */
7107 /* Now, build the VTT object itself. */
7110 /* Add the VTT to the vtables list. */
7115 }
7117 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
7118 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
7119 and CHAIN the vtable pointer for this binfo after construction is
7120 complete. VALUE can also be another BINFO, in which case we recurse. */
7122 static tree
7124 {
7125 tree vt;
7128 {
7134 else
7136 }
7139 }
7141 /* Data for secondary VTT initialization. */
7143 {
7144 /* Is this the primary VTT? */
7147 /* Current index into the VTT. */
7148 tree index;
7150 /* TREE_LIST of initializers built up. */
7151 tree inits;
7153 /* The type being constructed by this secondary VTT. */
7154 tree type_being_constructed;
7157 /* Recursively build the VTT-initializer for BINFO (which is in the
7158 hierarchy dominated by T). INITS points to the end of the initializer
7159 list to date. INDEX is the VTT index where the next element will be
7160 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
7161 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
7162 for virtual bases of T. When it is not so, we build the constructor
7163 vtables for the BINFO-in-T variant. */
7167 {
7169 tree b;
7170 tree init;
7171 tree secondary_vptrs;
7172 secondary_vptr_vtt_init_data data;
7175 /* We only need VTTs for subobjects with virtual bases. */
7179 /* We need to use a construction vtable if this is not the primary
7180 VTT. */
7182 {
7185 /* Record the offset in the VTT where this sub-VTT can be found. */
7187 }
7189 /* Add the address of the primary vtable for the complete object. */
7194 {
7197 }
7200 /* Recursively add the secondary VTTs for non-virtual bases. */
7205 /* Add secondary virtual pointers for all subobjects of BINFO with
7206 either virtual bases or reachable along a virtual path, except
7207 subobjects that are non-virtual primary bases. */
7217 /* The secondary vptrs come back in reverse order. After we reverse
7218 them, and add the INITS, the last init will be the first element
7219 of the chain. */
7222 {
7226 }
7229 /* Add the secondary VTTs for virtual bases in inheritance graph
7230 order. */
7232 {
7237 }
7238 else
7239 /* Remove the ctor vtables we created. */
7243 }
7245 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
7246 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
7248 static tree
7250 {
7253 /* We don't care about bases that don't have vtables. */
7257 /* We're only interested in proper subobjects of the type being
7258 constructed. */
7262 /* We're only interested in bases with virtual bases or reachable
7263 via a virtual path from the type being constructed. */
7268 /* We're not interested in non-virtual primary bases. */
7272 /* Record the index where this secondary vptr can be found. */
7274 {
7279 {
7280 /* It's a primary virtual base, and this is not a
7281 construction vtable. Find the base this is primary of in
7282 the inheritance graph, and use that base's vtable
7283 now. */
7286 }
7287 }
7289 /* Add the initializer for the secondary vptr itself. */
7292 /* Advance the vtt index. */
7297 }
7299 /* Called from build_vtt_inits via dfs_walk. After building
7300 constructor vtables and generating the sub-vtt from them, we need
7301 to restore the BINFO_VTABLES that were scribbled on. DATA is the
7302 binfo of the base whose sub vtt was generated. */
7304 static tree
7306 {
7310 /* If this class has no vtable, none of its bases do. */
7314 /* This might be a primary base, so have no vtable in this
7315 hierarchy. */
7318 /* If we scribbled the construction vtable vptr into BINFO, clear it
7319 out now. */
7325 }
7327 /* Build the construction vtable group for BINFO which is in the
7328 hierarchy dominated by T. */
7330 static void
7332 {
7333 tree list;
7334 tree type;
7335 tree vtbl;
7336 tree inits;
7337 tree id;
7338 tree vbase;
7340 /* See if we've already created this construction vtable group. */
7346 /* Build a version of VTBL (with the wrong type) for use in
7347 constructing the addresses of secondary vtables in the
7348 construction vtable group. */
7355 /* Add the vtables for each of our virtual bases using the vbase in T
7356 binfo. */
7358 vbase;
7360 {
7361 tree b;
7368 }
7371 /* Figure out the type of the construction vtable. */
7379 /* Initialize the construction vtable. */
7383 }
7385 /* Add the vtbl initializers for BINFO (and its bases other than
7386 non-virtual primaries) to the list of INITS. BINFO is in the
7387 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
7388 the constructor the vtbl inits should be accumulated for. (If this
7389 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
7390 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
7391 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
7392 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
7393 but are not necessarily the same in terms of layout. */
7395 static void
7397 tree orig_binfo,
7398 tree rtti_binfo,
7399 tree t,
7400 tree inits)
7401 {
7403 tree base_binfo;
7408 /* If it doesn't have a vptr, we don't do anything. */
7412 /* If we're building a construction vtable, we're not interested in
7413 subobjects that don't require construction vtables. */
7419 /* Build the initializers for the BINFO-in-T vtable. */
7425 /* Walk the BINFO and its bases. We walk in preorder so that as we
7426 initialize each vtable we can figure out at what offset the
7427 secondary vtable lies from the primary vtable. We can't use
7428 dfs_walk here because we need to iterate through bases of BINFO
7429 and RTTI_BINFO simultaneously. */
7431 {
7432 /* Skip virtual bases. */
7438 inits);
7439 }
7440 }
7442 /* Called from accumulate_vtbl_inits. Returns the initializers for
7443 the BINFO vtable. */
7445 static tree
7447 tree orig_binfo,
7448 tree rtti_binfo,
7449 tree t,
7450 tree l)
7451 {
7458 {
7459 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
7460 primary virtual base. If it is not the same primary in
7461 the hierarchy of T, we'll need to generate a ctor vtable
7462 for it, to place at its location in T. If it is the same
7463 primary, we still need a VTT entry for the vtable, but it
7464 should point to the ctor vtable for the base it is a
7465 primary for within the sub-hierarchy of RTTI_BINFO.
7467 There are three possible cases:
7469 1) We are in the same place.
7470 2) We are a primary base within a lost primary virtual base of
7471 RTTI_BINFO.
7472 3) We are primary to something not a base of RTTI_BINFO. */
7474 tree b;
7477 /* First, look through the bases we are primary to for RTTI_BINFO
7478 or a virtual base. */
7481 {
7486 }
7487 /* If we run out of primary links, keep looking down our
7488 inheritance chain; we might be an indirect primary. */
7492 found:
7494 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
7495 base B and it is a base of RTTI_BINFO, this is case 2. In
7496 either case, we share our vtable with LAST, i.e. the
7497 derived-most base within B of which we are a primary. */
7500 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
7501 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
7502 binfo_ctor_vtable after everything's been set up. */
7505 /* Otherwise, this is case 3 and we get our own. */
7506 }
7511 {
7512 tree index;
7515 /* Compute the initializer for this vtable. */
7519 /* Figure out the position to which the VPTR should point. */
7527 index);
7529 }
7532 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
7533 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
7534 straighten this out. */
7538 else
7539 /* For an ordinary vtable, set BINFO_VTABLE. */
7543 }
7547 /* Construct the initializer for BINFO's virtual function table. BINFO
7548 is part of the hierarchy dominated by T. If we're building a
7549 construction vtable, the ORIG_BINFO is the binfo we should use to
7550 find the actual function pointers to put in the vtable - but they
7551 can be overridden on the path to most-derived in the graph that
7552 ORIG_BINFO belongs. Otherwise,
7553 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
7554 BINFO that should be indicated by the RTTI information in the
7555 vtable; it will be a base class of T, rather than T itself, if we
7556 are building a construction vtable.
7558 The value returned is a TREE_LIST suitable for wrapping in a
7559 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
7560 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
7561 number of non-function entries in the vtable.
7563 It might seem that this function should never be called with a
7564 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
7565 base is always subsumed by a derived class vtable. However, when
7566 we are building construction vtables, we do build vtables for
7567 primary bases; we need these while the primary base is being
7568 constructed. */
7570 static tree
7572 tree orig_binfo,
7573 tree t,
7574 tree rtti_binfo,
7576 {
7578 tree vfun_inits;
7579 vtbl_init_data vid;
7581 tree vbinfo;
7584 /* Initialize VID. */
7593 /* The first vbase or vcall offset is at index -3 in the vtable. */
7596 /* Add entries to the vtable for RTTI. */
7599 /* Create an array for keeping track of the functions we've
7600 processed. When we see multiple functions with the same
7601 signature, we share the vcall offsets. */
7603 /* Add the vcall and vbase offset entries. */
7606 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
7607 build_vbase_offset_vtbl_entries. */
7612 /* If the target requires padding between data entries, add that now. */
7614 {
7618 {
7625 null_pointer_node),
7626 add);
7628 }
7629 }
7634 /* Go through all the ordinary virtual functions, building up
7635 initializers. */
7638 {
7639 tree delta;
7640 tree vcall_index;
7647 {
7651 {
7654 }
7656 }
7658 /* If the only definition of this function signature along our
7659 primary base chain is from a lost primary, this vtable slot will
7660 never be used, so just zero it out. This is important to avoid
7661 requiring extra thunks which cannot be generated with the function.
7663 We first check this in update_vtable_entry_for_fn, so we handle
7664 restored primary bases properly; we also need to do it here so we
7665 zero out unused slots in ctor vtables, rather than filling them
7666 with erroneous values (though harmless, apart from relocation
7667 costs). */
7669 {
7670 /* We found a defn before a lost primary; go ahead as normal. */
7674 /* The nearest definition is from a lost primary; clear the
7675 slot. */
7677 {
7680 }
7681 }
7684 {
7685 /* Pull the offset for `this', and the function to call, out of
7686 the list. */
7693 /* You can't call an abstract virtual function; it's abstract.
7694 So, we replace these functions with __pure_virtual. */
7696 {
7701 }
7702 else
7703 {
7705 {
7709 }
7710 /* Take the address of the function, considering it to be of an
7711 appropriate generic type. */
7713 }
7714 }
7716 /* And add it to the chain of initializers. */
7718 {
7723 else
7725 {
7732 }
7733 }
7734 else
7736 }
7738 /* The initializers for virtual functions were built up in reverse
7739 order; straighten them out now. */
7742 /* The negative offset initializers are also in reverse order. */
7745 /* Chain the two together. */
7747 }
7749 /* Adds to vid->inits the initializers for the vbase and vcall
7750 offsets in BINFO, which is in the hierarchy dominated by T. */
7752 static void
7754 {
7755 tree b;
7757 /* If this is a derived class, we must first create entries
7758 corresponding to the primary base class. */
7763 /* Add the vbase entries for this base. */
7765 /* Add the vcall entries for this base. */
7767 }
7769 /* Returns the initializers for the vbase offset entries in the vtable
7770 for BINFO (which is part of the class hierarchy dominated by T), in
7771 reverse order. VBASE_OFFSET_INDEX gives the vtable index
7772 where the next vbase offset will go. */
7774 static void
7776 {
7777 tree vbase;
7778 tree t;
7779 tree non_primary_binfo;
7781 /* If there are no virtual baseclasses, then there is nothing to
7782 do. */
7788 /* We might be a primary base class. Go up the inheritance hierarchy
7789 until we find the most derived class of which we are a primary base:
7790 it is the offset of that which we need to use. */
7793 {
7794 tree b;
7796 /* If we have reached a virtual base, then it must be a primary
7797 base (possibly multi-level) of vid->binfo, or we wouldn't
7798 have called build_vcall_and_vbase_vtbl_entries for it. But it
7799 might be a lost primary, so just skip down to vid->binfo. */
7801 {
7804 }
7810 }
7812 /* Go through the virtual bases, adding the offsets. */
7814 vbase;
7816 {
7817 tree b;
7818 tree delta;
7823 /* Find the instance of this virtual base in the complete
7824 object. */
7827 /* If we've already got an offset for this virtual base, we
7828 don't need another one. */
7833 /* Figure out where we can find this vbase offset. */
7842 /* The vbase offset had better be the same. */
7845 /* The next vbase will come at a more negative offset. */
7849 /* The initializer is the delta from BINFO to this virtual base.
7850 The vbase offsets go in reverse inheritance-graph order, and
7851 we are walking in inheritance graph order so these end up in
7852 the right order. */
7859 vtable_entry_type,
7860 delta));
7862 }
7863 }
7865 /* Adds the initializers for the vcall offset entries in the vtable
7866 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
7867 to VID->INITS. */
7869 static void
7871 {
7872 /* We only need these entries if this base is a virtual base. We
7873 compute the indices -- but do not add to the vtable -- when
7874 building the main vtable for a class. */
7877 /* If BINFO is RTTI_BINFO, then (since BINFO does not
7878 correspond to VID->DERIVED), we are building a primary
7879 construction virtual table. Since this is a primary
7880 virtual table, we do not need the vcall offsets for
7881 BINFO. */
7883 {
7884 /* We need a vcall offset for each of the virtual functions in this
7885 vtable. For example:
7887 class A { virtual void f (); };
7888 class B1 : virtual public A { virtual void f (); };
7889 class B2 : virtual public A { virtual void f (); };
7890 class C: public B1, public B2 { virtual void f (); };
7892 A C object has a primary base of B1, which has a primary base of A. A
7893 C also has a secondary base of B2, which no longer has a primary base
7894 of A. So the B2-in-C construction vtable needs a secondary vtable for
7895 A, which will adjust the A* to a B2* to call f. We have no way of
7896 knowing what (or even whether) this offset will be when we define B2,
7897 so we store this "vcall offset" in the A sub-vtable and look it up in
7898 a "virtual thunk" for B2::f.
7900 We need entries for all the functions in our primary vtable and
7901 in our non-virtual bases' secondary vtables. */
7903 /* If we are just computing the vcall indices -- but do not need
7904 the actual entries -- not that. */
7907 /* Now, walk through the non-virtual bases, adding vcall offsets. */
7909 }
7910 }
7912 /* Build vcall offsets, starting with those for BINFO. */
7914 static void
7916 {
7918 tree primary_binfo;
7919 tree base_binfo;
7921 /* Don't walk into virtual bases -- except, of course, for the
7922 virtual base for which we are building vcall offsets. Any
7923 primary virtual base will have already had its offsets generated
7924 through the recursion in build_vcall_and_vbase_vtbl_entries. */
7928 /* If BINFO has a primary base, process it first. */
7933 /* Add BINFO itself to the list. */
7936 /* Scan the non-primary bases of BINFO. */
7940 }
7942 /* Called from build_vcall_offset_vtbl_entries_r. */
7944 static void
7946 {
7947 /* Make entries for the rest of the virtuals. */
7949 {
7950 tree orig_fn;
7952 /* The ABI requires that the methods be processed in declaration
7953 order. G++ 3.2 used the order in the vtable. */
7955 orig_fn;
7959 }
7960 else
7961 {
7962 tree derived_virtuals;
7963 tree base_virtuals;
7964 tree orig_virtuals;
7965 /* If BINFO is a primary base, the most derived class which has
7966 BINFO as a primary base; otherwise, just BINFO. */
7967 tree non_primary_binfo;
7969 /* We might be a primary base class. Go up the inheritance hierarchy
7970 until we find the most derived class of which we are a primary base:
7971 it is the BINFO_VIRTUALS there that we need to consider. */
7974 {
7975 tree b;
7977 /* If we have reached a virtual base, then it must be vid->vbase,
7978 because we ignore other virtual bases in
7979 add_vcall_offset_vtbl_entries_r. In turn, it must be a primary
7980 base (possibly multi-level) of vid->binfo, or we wouldn't
7981 have called build_vcall_and_vbase_vtbl_entries for it. But it
7982 might be a lost primary, so just skip down to vid->binfo. */
7984 {
7988 }
7994 }
7997 /* For a ctor vtable we need the equivalent binfo within the hierarchy
7998 where rtti_binfo is the most derived type. */
7999 non_primary_binfo
8005 base_virtuals;
8009 {
8010 tree orig_fn;
8012 /* Find the declaration that originally caused this function to
8013 be present in BINFO_TYPE (binfo). */
8016 /* When processing BINFO, we only want to generate vcall slots for
8017 function slots introduced in BINFO. So don't try to generate
8018 one if the function isn't even defined in BINFO. */
8023 }
8024 }
8025 }
8027 /* Add a vcall offset entry for ORIG_FN to the vtable. */
8029 static void
8031 {
8033 tree vcall_offset;
8034 tree derived_entry;
8036 /* If there is already an entry for a function with the same
8037 signature as FN, then we do not need a second vcall offset.
8038 Check the list of functions already present in the derived
8039 class vtable. */
8041 {
8043 /* We only use one vcall offset for virtual destructors,
8044 even though there are two virtual table entries. */
8048 }
8050 /* If we are building these vcall offsets as part of building
8051 the vtable for the most derived class, remember the vcall
8052 offset. */
8054 {
8057 NULL);
8060 }
8062 /* The next vcall offset will be found at a more negative
8063 offset. */
8067 /* Keep track of this function. */
8071 {
8072 tree base;
8073 tree fn;
8075 /* Find the overriding function. */
8079 integer_zero_node);
8080 else
8081 {
8084 /* The vbase we're working on is a primary base of
8085 vid->binfo. But it might be a lost primary, so its
8086 BINFO_OFFSET might be wrong, so we just use the
8087 BINFO_OFFSET from vid->binfo. */
8093 vcall_offset);
8094 }
8095 /* Add the initializer to the vtable. */
8098 }
8099 }
8101 /* Return vtbl initializers for the RTTI entries corresponding to the
8102 BINFO's vtable. The RTTI entries should indicate the object given
8103 by VID->rtti_binfo. */
8105 static void
8107 {
8108 tree b;
8109 tree t;
8110 tree offset;
8111 tree decl;
8112 tree init;
8116 /* To find the complete object, we will first convert to our most
8117 primary base, and then add the offset in the vtbl to that value. */
8121 {
8122 tree primary_base;
8128 }
8132 /* The second entry is the address of the typeinfo object. */
8135 else
8138 /* Convert the declaration to a type that can be stored in the
8139 vtable. */
8144 /* Add the offset-to-top entry. It comes earlier in the vtable than
8145 the typeinfo entry. Convert the offset to look like a
8146 function pointer, so that we can put it in the vtable. */
8150 }
8152 /* Fold a OBJ_TYPE_REF expression to the address of a function.
8153 KNOWN_TYPE carries the true type of OBJ_TYPE_REF_OBJECT(REF). */
8155 tree
8157 {
8161 tree fndecl;
8164 {
8165 i += (TARGET_VTABLE_USES_DESCRIPTORS
8168 }
8172 #ifdef ENABLE_CHECKING
8175 #endif
8180 }