| blob | 66f42627715f891cc6b5d4ff2a5930e292a5dbbc |
1 /* Functions related to building classes and their related objects.
2 Copyright (C) 1987-2017 Free Software Foundation, Inc.
3 Contributed by Michael Tiemann (tiemann@cygnus.com)
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
10 any later version.
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
22 /* High-level class interface. */
40 /* Id for dumping the class hierarchy. */
43 /* The number of nested classes being processed. If we are not in the
44 scope of any class, this is zero. */
48 /* In order to deal with nested classes, we keep a stack of classes.
49 The topmost entry is the innermost class, and is the entry at index
50 CURRENT_CLASS_DEPTH */
53 /* The name of the class. */
54 tree name;
56 /* The _TYPE node for the class. */
57 tree type;
59 /* The access specifier pending for new declarations in the scope of
60 this class. */
61 tree access;
63 /* If were defining TYPE, the names used in this class. */
64 splay_tree names_used;
66 /* Nonzero if this class is no longer open, because of a call to
67 push_to_top_level. */
71 struct vtbl_init_data
72 {
73 /* The base for which we're building initializers. */
74 tree binfo;
75 /* The type of the most-derived type. */
76 tree derived;
77 /* The binfo for the dynamic type. This will be TYPE_BINFO (derived),
78 unless ctor_vtbl_p is true. */
79 tree rtti_binfo;
80 /* The negative-index vtable initializers built up so far. These
81 are in order from least negative index to most negative index. */
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. */
100 };
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. */
153 /* Used by find_flexarrays and related functions. */
204 tree *);
214 splay_tree_key k2);
223 /* Variables shared between class.c and call.c. */
233 /* Return a COND_EXPR that executes TRUE_STMT if this execution of the
234 'structor is in charge of 'structing virtual bases, or FALSE_STMT
235 otherwise. */
237 tree
239 {
249 }
251 /* Convert to or from a base subobject. EXPR is an expression of type
252 `A' or `A*', an expression of type `B' or `B*' is returned. To
253 convert A to a base B, CODE is PLUS_EXPR and BINFO is the binfo for
254 the B base instance within A. To convert base A to derived B, CODE
255 is MINUS_EXPR and BINFO is the binfo for the A instance within B.
256 In this latter case, A must not be a morally virtual base of B.
257 NONNULL is true if EXPR is known to be non-NULL (this is only
258 needed when EXPR is of pointer type). CV qualifiers are preserved
259 from EXPR. */
261 tree
263 tree expr,
264 tree binfo,
266 tsubst_flags_t complain)
267 {
270 tree probe;
271 tree offset;
272 tree target_type;
274 tree ptr_target_type;
285 {
291 }
299 {
300 /* This can happen when adjust_result_of_qualified_name_lookup can't
301 find a unique base binfo in a call to a member function. We
302 couldn't give the diagnostic then since we might have been calling
303 a static member function, so we do it now. In other cases, eg.
304 during error recovery (c++/71979), we may not have a base at all. */
306 {
310 }
312 }
319 /* Nothing to do. */
323 {
325 {
327 {
330 "pointer to derived class %qT because the base is "
332 else
336 }
337 else
338 {
344 else
348 }
349 }
351 }
354 {
356 /* This must happen before the call to save_expr. */
358 }
359 else
365 /* TARGET_TYPE has been extracted from BINFO, and, is therefore always
366 cv-unqualified. Extract the cv-qualifiers from EXPR so that the
367 expression returned matches the input. */
368 target_type = cp_build_qualified_type
372 /* Do we need to look in the vtable for the real offset? */
375 /* Don't bother with the calculations inside sizeof; they'll ICE if the
376 source type is incomplete and the pointer value doesn't matter. In a
377 template (even in instantiate_non_dependent_expr), we don't have vtables
378 set up properly yet, and the value doesn't matter there either; we're
379 just interested in the result of overload resolution. */
381 || processing_template_decl
383 {
386 }
388 /* If we're in an NSDMI, we don't have the full constructor context yet
389 that we need for converting to a virtual base, so just build a stub
390 CONVERT_EXPR and expand it later in bot_replace. */
393 {
397 }
399 /* Do we need to check for a null pointer? */
401 {
402 /* If we know the conversion will not actually change the value
403 of EXPR, then we can avoid testing the expression for NULL.
404 We have to avoid generating a COMPONENT_REF for a base class
405 field, because other parts of the compiler know that such
406 expressions are always non-NULL. */
410 }
412 /* Protect against multiple evaluation if necessary. */
416 /* Now that we've saved expr, build the real null test. */
418 {
422 /* This is a compiler generated comparison, don't emit
423 e.g. -Wnonnull-compare warning for it. */
425 }
427 /* If this is a simple base reference, express it as a COMPONENT_REF. */
429 /* We don't build base fields for empty bases, and they aren't very
430 interesting to the optimizers anyway. */
432 {
441 }
444 {
445 /* Going via virtual base V_BINFO. We need the static offset
446 from V_BINFO to BINFO, and the dynamic offset from D_BINFO to
447 V_BINFO. That offset is an entry in D_BINFO's vtable. */
448 tree v_offset;
451 {
452 /* In a base member initializer, we cannot rely on the
453 vtable being set up. We have to indirect via the
454 vtt_parm. */
455 tree t;
461 }
462 else
463 {
466 {
471 }
473 complain),
475 }
483 v_offset);
495 /* Negative fixed_type_p means this is a constructor or destructor;
496 virtual base layout is fixed in in-charge [cd]tors, but not in
497 base [cd]tors. */
498 offset = build_if_in_charge
500 v_offset);
501 else
503 }
511 {
516 }
517 else
520 indout:
522 {
526 }
528 out:
534 }
536 /* Subroutine of build_base_path; EXPR and BINFO are as in that function.
537 Perform a derived-to-base conversion by recursively building up a
538 sequence of COMPONENT_REFs to the appropriate base fields. */
540 static tree
542 {
545 tree field;
548 {
549 tree temp;
553 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x'
554 into `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only
555 an lvalue in the front end; only _DECLs and _REFs are lvalues
556 in the back end. */
562 }
564 /* Recurse. */
569 /* Is this the base field created by build_base_field? */
573 /* If we're looking for a field in the most-derived class,
574 also check the field offset; we can have two base fields
575 of the same type if one is an indirect virtual base and one
576 is a direct non-virtual base. */
580 {
581 /* We don't use build_class_member_access_expr here, as that
582 has unnecessary checks, and more importantly results in
583 recursive calls to dfs_walk_once. */
589 /* Mark the expression const or volatile, as appropriate.
590 Even though we've dealt with the type above, we still have
591 to mark the expression itself. */
598 }
600 /* Didn't find the base field?!? */
602 }
604 /* Convert OBJECT to the base TYPE. OBJECT is an expression whose
605 type is a class type or a pointer to a class type. In the former
606 case, TYPE is also a class type; in the latter it is another
607 pointer type. If CHECK_ACCESS is true, an error message is emitted
608 if TYPE is inaccessible. If OBJECT has pointer type, the value is
609 assumed to be non-NULL. */
611 tree
613 tsubst_flags_t complain)
614 {
615 tree binfo;
616 tree object_type;
619 {
622 }
623 else
632 }
634 /* EXPR is an expression with unqualified class type. BASE is a base
635 binfo of that class type. Returns EXPR, converted to the BASE
636 type. This function assumes that EXPR is the most derived class;
637 therefore virtual bases can be found at their static offsets. */
639 tree
641 {
642 tree expr_type;
646 {
647 /* If this is a non-empty base, use a COMPONENT_REF. */
651 /* We use fold_build2 and fold_convert below to simplify the trees
652 provided to the optimizers. It is not safe to call these functions
653 when processing a template because they do not handle C++-specific
654 trees. */
662 }
665 }
667 \f
668 tree
670 {
674 /* Can happen in case of duplicate base types (c++/59082). */
678 /* First, convert to the requested type. */
683 /* Second, the requested type may not be the owner of its own vptr.
684 If not, convert to the base class that owns it. We cannot use
685 convert_to_base here, because VCONTEXT may appear more than once
686 in the inheritance hierarchy of TYPE, and thus direct conversion
687 between the types may be ambiguous. Following the path back up
688 one step at a time via primary bases avoids the problem. */
692 {
695 }
698 }
700 /* Given an object INSTANCE, return an expression which yields the
701 vtable element corresponding to INDEX. There are many special
702 cases for INSTANCE which we take care of here, mainly to avoid
703 creating extra tree nodes when we don't have to. */
705 static tree
707 {
708 tree aref;
711 /* Try to figure out what a reference refers to, and
712 access its virtual function table directly. */
720 {
725 }
734 }
736 tree
738 {
742 }
744 /* Given a stable object pointer INSTANCE_PTR, return an expression which
745 yields a function pointer corresponding to vtable element INDEX. */
747 tree
749 {
750 tree aref;
753 tf_warning_or_error),
754 idx);
756 /* When using function descriptors, the address of the
757 vtable entry is treated as a function pointer. */
762 /* Remember this as a method reference, for later devirtualization. */
766 }
768 /* Return the name of the virtual function table (as an IDENTIFIER_NODE)
769 for the given TYPE. */
771 static tree
773 {
775 }
777 /* DECL is an entity associated with TYPE, like a virtual table or an
778 implicitly generated constructor. Determine whether or not DECL
779 should have external or internal linkage at the object file
780 level. This routine does not deal with COMDAT linkage and other
781 similar complexities; it simply sets TREE_PUBLIC if it possible for
782 entities in other translation units to contain copies of DECL, in
783 the abstract. */
785 void
787 {
790 }
792 /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE.
793 (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.)
794 Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */
796 static tree
798 {
799 tree decl;
802 /* vtable names are already mangled; give them their DECL_ASSEMBLER_NAME
803 now to avoid confusion in mangle_decl. */
814 /* The vtable has not been defined -- yet. */
818 /* Mark the VAR_DECL node representing the vtable itself as a
819 "gratuitous" one, thereby forcing dwarfout.c to ignore it. It
820 is rather important that such things be ignored because any
821 effort to actually generate DWARF for them will run into
822 trouble when/if we encounter code like:
824 #pragma interface
825 struct S { virtual void member (); };
827 because the artificial declaration of the vtable itself (as
828 manufactured by the g++ front end) will say that the vtable is
829 a static member of `S' but only *after* the debug output for
830 the definition of `S' has already been output. This causes
831 grief because the DWARF entry for the definition of the vtable
832 will try to refer back to an earlier *declaration* of the
833 vtable as a static member of `S' and there won't be one. We
834 might be able to arrange to have the "vtable static member"
835 attached to the member list for `S' before the debug info for
836 `S' get written (which would solve the problem) but that would
837 require more intrusive changes to the g++ front end. */
841 }
843 /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic,
844 or even complete. If this does not exist, create it. If COMPLETE is
845 nonzero, then complete the definition of it -- that will render it
846 impossible to actually build the vtable, but is useful to get at those
847 which are known to exist in the runtime. */
849 tree
851 {
852 tree decl;
861 {
864 }
867 }
869 /* Build the primary virtual function table for TYPE. If BINFO is
870 non-NULL, build the vtable starting with the initial approximation
871 that it is the same as the one which is the head of the association
872 list. Returns a nonzero value if a new vtable is actually
873 created. */
875 static int
877 {
878 tree decl;
879 tree virtuals;
884 {
886 /* We have already created a vtable for this base, so there's
887 no need to do it again. */
894 }
895 else
896 {
899 }
902 {
905 }
907 /* Initialize the association list for this type, based
908 on our first approximation. */
913 }
915 /* Give BINFO a new virtual function table which is initialized
916 with a skeleton-copy of its original initialization. The only
917 entry that changes is the `delta' entry, so we can really
918 share a lot of structure.
920 FOR_TYPE is the most derived type which caused this table to
921 be needed.
923 Returns nonzero if we haven't met BINFO before.
925 The order in which vtables are built (by calling this function) for
926 an object must remain the same, otherwise a binary incompatibility
927 can result. */
929 static int
931 {
933 /* We already created a vtable for this base. There's no need to
934 do it again. */
937 /* Remember that we've created a vtable for this BINFO, so that we
938 don't try to do so again. */
941 /* Make fresh virtual list, so we can smash it later. */
944 /* Secondary vtables are laid out as part of the same structure as
945 the primary vtable. */
948 }
950 /* Create a new vtable for BINFO which is the hierarchy dominated by
951 T. Return nonzero if we actually created a new vtable. */
953 static int
955 {
957 /* In this case, it is *type*'s vtable we are modifying. We start
958 with the approximation that its vtable is that of the
959 immediate base class. */
961 else
962 /* This is our very own copy of `basetype' to play with. Later,
963 we will fill in all the virtual functions that override the
964 virtual functions in these base classes which are not defined
965 by the current type. */
967 }
969 /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO
970 (which is in the hierarchy dominated by T) list FNDECL as its
971 BV_FN. DELTA is the required constant adjustment from the `this'
972 pointer where the vtable entry appears to the `this' required when
973 the function is actually called. */
975 static void
977 tree binfo,
978 tree fndecl,
979 tree delta,
981 {
982 tree v;
988 {
989 /* We need a new vtable for BINFO. */
991 {
992 /* If we really did make a new vtable, we also made a copy
993 of the BINFO_VIRTUALS list. Now, we have to find the
994 corresponding entry in that list. */
999 }
1004 }
1005 }
1007 \f
1008 /* Add method METHOD to class TYPE. If VIA_USING indicates whether
1009 METHOD is being injected via a using_decl. Returns true if the
1010 method could be added to the method vec. */
1012 bool
1014 {
1021 tree current_fns;
1034 {
1035 /* Make a new method vector. We start with 8 entries. We must
1036 allocate at least two (for constructors and destructors), and
1037 we're going to end up with an assignment operator at some
1038 point as well. */
1040 /* Create slots for constructors and destructors. */
1044 }
1046 /* Maintain TYPE_HAS_USER_CONSTRUCTOR, etc. */
1049 /* Constructors and destructors go in special slots. */
1054 else
1055 {
1056 tree m;
1059 /* See if we already have an entry with this name. */
1063 {
1066 {
1071 }
1075 {
1078 }
1083 }
1084 }
1087 /* Check to see if we've already got this method. */
1089 {
1091 tree fn_type;
1092 tree method_type;
1093 tree parms1;
1094 tree parms2;
1099 /* Two using-declarations can coexist, we'll complain about ambiguity in
1100 overload resolution. */
1102 /* Except handle inherited constructors specially. */
1106 /* [over.load] Member function declarations with the
1107 same name and the same parameter types cannot be
1108 overloaded if any of them is a static member
1109 function declaration.
1111 [over.load] Member function declarations with the same name and
1112 the same parameter-type-list as well as member function template
1113 declarations with the same name, the same parameter-type-list, and
1114 the same template parameter lists cannot be overloaded if any of
1115 them, but not all, have a ref-qualifier.
1117 [namespace.udecl] When a using-declaration brings names
1118 from a base class into a derived class scope, member
1119 functions in the derived class override and/or hide member
1120 functions with the same name and parameter types in a base
1121 class (rather than conflicting). */
1127 /* Compare the quals on the 'this' parm. Don't compare
1128 the whole types, as used functions are treated as
1129 coming from the using class in overload resolution. */
1132 /* Either both or neither need to be ref-qualified for
1133 differing quals to allow overloading. */
1140 /* For templates, the return type and template parameters
1141 must be identical. */
1154 /* Bring back parameters omitted from an inherited ctor. */
1165 {
1166 /* For function versions, their parms and types match
1167 but they are not duplicates. Record function versions
1168 as and when they are found. extern "C" functions are
1169 not treated as versions. */
1175 {
1176 /* Mark functions as versions if necessary. Modify the mangled
1177 decl name if necessary. */
1179 {
1183 }
1185 {
1189 }
1192 }
1195 {
1197 {
1201 {
1203 {
1204 /* Inheriting the same constructor along different
1205 paths, combine them. */
1206 SET_DECL_INHERITED_CTOR
1209 /* And discard the new one. */
1211 }
1212 else
1213 /* Inherited ctors can coexist until overload
1214 resolution. */
1216 }
1221 basef);
1222 }
1223 /* Otherwise defer to the other function. */
1225 }
1228 /* Defer to the local function. */
1232 {
1233 /* Remove the inherited constructor. */
1236 }
1237 else
1238 {
1242 }
1243 }
1244 }
1246 /* A class should never have more than one destructor. */
1258 {
1261 /* We only expect to add few methods in the COMPLETE_P case, so
1262 just make room for one more method in that case. */
1265 else
1271 else
1273 }
1274 else
1275 /* Replace the current slot. */
1278 }
1280 /* Subroutines of finish_struct. */
1282 /* Change the access of FDECL to ACCESS in T. Return 1 if change was
1283 legit, otherwise return 0. */
1285 static int
1287 {
1288 tree elem;
1296 {
1298 {
1302 else
1305 }
1306 else
1307 {
1308 /* They're changing the access to the same thing they changed
1309 it to before. That's OK. */
1310 ;
1311 }
1312 }
1313 else
1314 {
1316 tf_warning_or_error);
1319 }
1321 }
1323 /* Return the access node for DECL's access in its enclosing class. */
1325 tree
1327 {
1331 }
1333 /* Process the USING_DECL, which is a member of T. */
1335 static void
1337 {
1342 tree old_value;
1347 tf_warning_or_error);
1349 {
1354 else
1356 }
1364 ;
1366 {
1368 /* It's OK to use functions from a base when there are functions with
1370 else
1371 {
1374 old_value);
1376 }
1377 }
1379 {
1383 }
1385 /* Make type T see field decl FDECL with access ACCESS. */
1388 {
1391 }
1392 else
1394 }
1395 \f
1396 /* Data structure for find_abi_tags_r, below. */
1398 struct abi_tag_data
1399 {
1403 };
1405 /* Subroutine of find_abi_tags_r. Handle a single TAG found on the class TP
1406 in the context of P. TAG can be either an identifier (the DECL_NAME of
1407 a tag NAMESPACE_DECL) or a STRING_CST (a tag attribute). */
1409 static void
1411 {
1413 {
1415 {
1416 /* We're collecting tags from template arguments or from
1417 the type of a variable or function return type. */
1420 /* Don't inherit this tag multiple times. */
1424 {
1425 /* Tags inherited from type template arguments are only used
1426 to avoid warnings. */
1429 }
1430 /* For functions and variables we want to warn, too. */
1431 }
1433 /* Otherwise we're diagnosing missing tags. */
1435 {
1440 }
1442 {
1446 }
1448 {
1453 }
1454 else
1455 {
1459 {
1463 }
1464 }
1465 }
1466 }
1468 /* Find all the ABI tags in the attribute list ATTR and either call
1469 check_tag (if TP is non-null) or set IDENTIFIER_MARKED to val. */
1471 static void
1473 {
1480 {
1485 else
1487 }
1488 }
1490 /* Find all the ABI tags on T and its enclosing scopes and either call
1491 check_tag (if TP is non-null) or set IDENTIFIER_MARKED to val. */
1493 static void
1495 {
1497 {
1498 tree attr;
1500 {
1503 }
1504 else
1505 {
1508 }
1510 }
1511 }
1513 /* walk_tree callback for check_abi_tags: if the type at *TP involves any
1514 types with ABI tags, add the corresponding identifiers to the VEC in
1515 *DATA and set IDENTIFIER_MARKED. */
1517 static tree
1519 {
1523 /* walk_tree shouldn't be walking into any subtrees of a RECORD_TYPE
1524 anyway, but let's make sure of it. */
1532 }
1534 /* walk_tree callback for mark_abi_tags: if *TP is a class, set
1535 IDENTIFIER_MARKED on its ABI tags. */
1537 static tree
1539 {
1543 /* walk_tree shouldn't be walking into any subtrees of a RECORD_TYPE
1544 anyway, but let's make sure of it. */
1552 }
1554 /* Set IDENTIFIER_MARKED on all the ABI tags on T and its enclosing
1555 scopes. */
1557 static void
1559 {
1562 {
1565 {
1566 /* Template arguments are part of the signature. */
1569 {
1572 }
1573 }
1575 /* A function's parameter types are part of the signature, so
1576 we don't need to inherit any tags that are also in them. */
1581 }
1582 }
1584 /* Check that T has all the ABI tags that subobject SUBOB has, or
1585 warn if not. If T is a (variable or function) declaration, also
1586 return any missing tags, and add them to T if JUST_CHECKING is false. */
1588 static tree
1590 {
1598 /* No need to worry about things local to this TU. */
1614 {
1617 }
1618 else
1619 {
1623 else
1627 }
1632 }
1634 /* Check that DECL has all the ABI tags that are used in parts of its type
1635 that are not reflected in its mangled name. */
1637 void
1639 {
1646 }
1648 /* Return any ABI tags that are used in parts of the type of DECL
1649 that are not reflected in its mangled name. This function is only
1650 used in backward-compatible mangling for ABI <11. */
1652 tree
1654 {
1658 /* Don't check DECL_CONV_FN_P here like we do in check_abi_tags, so
1659 that we can use this function for setting need_abi_warning
1660 regardless of the current flag_abi_version. */
1663 else
1665 }
1667 void
1669 {
1679 {
1682 {
1686 }
1687 }
1689 // If we found some tags on our template arguments, add them to our
1690 // abi_tag attribute.
1692 {
1696 else
1700 }
1703 }
1705 /* Return true, iff class T has a non-virtual destructor that is
1706 accessible from outside the class heirarchy (i.e. is public, or
1707 there's a suitable friend. */
1709 static bool
1711 {
1714 /* An implicitly declared destructor is always public. And,
1715 if it were virtual, we would have created it by now. */
1730 }
1732 /* Run through the base classes of T, updating CANT_HAVE_CONST_CTOR_P,
1733 and NO_CONST_ASN_REF_P. Also set flag bits in T based on
1734 properties of the bases. */
1736 static void
1740 {
1744 tree base_binfo;
1745 tree binfo;
1755 {
1764 /* If any base class is non-literal, so is the derived class. */
1768 /* If the base class doesn't have copy constructors or
1769 assignment operators that take const references, then the
1770 derived class cannot have such a member automatically
1771 generated. */
1780 /* A virtual base does not effect nearly emptiness. */
1781 ;
1783 {
1785 /* And if there is more than one nearly empty base, then the
1786 derived class is not nearly empty either. */
1788 else
1789 /* Remember we've seen one. */
1791 }
1793 /* If the base class is not empty or nearly empty, then this
1794 class cannot be nearly empty. */
1797 /* A lot of properties from the bases also apply to the derived
1798 class. */
1815 SET_CLASSTYPE_READONLY_FIELDS_NEED_INIT
1818 SET_CLASSTYPE_REF_FIELDS_NEED_INIT
1824 /* A standard-layout class is a class that:
1825 ...
1826 * has no non-standard-layout base classes, */
1829 {
1830 tree basefield;
1831 /* ...has no base classes of the same type as the first non-static
1832 data member... */
1834 && (same_type_ignoring_top_level_qualifiers_p
1837 else
1838 /* ...either has no non-static data members in the most-derived
1839 class and at most one base class with non-static data
1840 members, or has no base classes with non-static data
1841 members */
1847 {
1850 else
1853 }
1854 }
1856 /* Don't bother collecting tm attributes if transactional memory
1857 support is not enabled. */
1859 {
1863 }
1866 }
1868 /* If one of the base classes had TM attributes, and the current class
1869 doesn't define its own, then the current class inherits one. */
1871 {
1874 }
1875 }
1877 /* Determine all the primary bases within T. Sets BINFO_PRIMARY_BASE_P for
1878 those that are primaries. Sets BINFO_LOST_PRIMARY_P for those
1879 that have had a nearly-empty virtual primary base stolen by some
1880 other base in the hierarchy. Determines CLASSTYPE_PRIMARY_BASE for
1881 T. */
1883 static void
1885 {
1889 tree base_binfo;
1891 /* Determine the primary bases of our bases. */
1894 {
1897 /* See if we're the non-virtual primary of our inheritance
1898 chain. */
1900 {
1907 /* We are the primary binfo. */
1909 }
1910 /* Determine if we have a virtual primary base, and mark it so.
1911 */
1913 {
1917 /* Someone already claimed this base. */
1919 else
1920 {
1921 tree delta;
1926 /* A virtual binfo might have been copied from within
1927 another hierarchy. As we're about to use it as a
1928 primary base, make sure the offsets match. */
1936 }
1937 }
1938 }
1940 /* First look for a dynamic direct non-virtual base. */
1942 {
1946 {
1949 }
1950 }
1952 /* A "nearly-empty" virtual base class can be the primary base
1953 class, if no non-virtual polymorphic base can be found. Look for
1954 a nearly-empty virtual dynamic base that is not already a primary
1955 base of something in the hierarchy. If there is no such base,
1956 just pick the first nearly-empty virtual base. */
1962 {
1964 {
1965 /* Found one that is not primary. */
1968 }
1970 /* Remember the first candidate. */
1972 }
1974 found:
1975 /* If we've got a primary base, use it. */
1977 {
1982 /* We are stealing a primary base. */
1986 {
1987 tree delta;
1990 /* A virtual binfo might have been copied from within
1991 another hierarchy. As we're about to use it as a primary
1992 base, make sure the offsets match. */
1997 }
2004 }
2005 }
2007 /* Update the variant types of T. */
2009 void
2011 {
2012 tree variants;
2018 variants;
2020 {
2021 /* These fields are in the _TYPE part of the node, not in
2022 the TYPE_LANG_SPECIFIC component, so they are not shared. */
2032 /* Copy whatever these are holding today. */
2035 }
2036 }
2038 /* KLASS is a class that we're applying may_alias to after the body is
2039 parsed. Fixup any POINTER_TO and REFERENCE_TO types. The
2040 canonical type(s) will be implicitly updated. */
2042 static void
2044 {
2053 }
2055 /* Early variant fixups: we apply attributes at the beginning of the class
2056 definition, and we need to fix up any variants that have already been
2057 made via elaborated-type-specifier so that check_qualified_type works. */
2059 void
2061 {
2062 tree variants;
2076 variants;
2078 {
2079 /* These are the two fields that check_qualified_type looks at and
2080 are affected by attributes. */
2085 else
2090 }
2091 }
2092 \f
2093 /* Set memoizing fields and bits of T (and its variants) for later
2094 use. */
2096 static void
2098 {
2099 /* Fix up variants (if any). */
2103 /* For a class w/o baseclasses, 'finish_struct' has set
2104 CLASSTYPE_PURE_VIRTUALS correctly (by definition).
2105 Similarly for a class whose base classes do not have vtables.
2106 When neither of these is true, we might have removed abstract
2107 virtuals (by providing a definition), added some (by declaring
2108 new ones), or redeclared ones from a base class. We need to
2109 recalculate what's really an abstract virtual at this point (by
2110 looking in the vtables). */
2113 /* If this type has a copy constructor or a destructor, force its
2114 mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be
2115 nonzero. This will cause it to be passed by invisible reference
2116 and prevent it from being returned in a register. */
2119 {
2120 tree variants;
2123 {
2126 }
2127 }
2128 }
2130 /* Issue warnings about T having private constructors, but no friends,
2131 and so forth.
2133 HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or
2134 static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any
2135 non-private static member functions. */
2137 static void
2139 {
2142 tree fn;
2145 /* If the class has friends, those entities might create and
2146 access instances, so we should not warn. */
2149 /* We will have warned when the template was declared; there's
2150 no need to warn on every instantiation. */
2152 /* There's no reason to even consider warning about this
2153 class. */
2156 /* We only issue one warning, if more than one applies, because
2157 otherwise, on code like:
2159 class A {
2160 // Oops - forgot `public:'
2161 A();
2162 A(const A&);
2163 ~A();
2164 };
2166 we warn several times about essentially the same problem. */
2168 /* Check to see if all (non-constructor, non-destructor) member
2169 functions are private. (Since there are no friends or
2170 non-private statics, we can't ever call any of the private member
2171 functions.) */
2173 /* We're not interested in compiler-generated methods; they don't
2174 provide any way to call private members. */
2176 {
2178 {
2180 /* A non-private static member function is just like a
2181 friend; it can create and invoke private member
2182 functions, and be accessed without a class
2183 instance. */
2187 /* Keep searching for a static member function. */
2188 }
2191 }
2194 {
2195 /* There are no non-private methods, and there's at least one
2196 private member function that isn't a constructor or
2197 destructor. (If all the private members are
2198 constructors/destructors we want to use the code below that
2199 issues error messages specifically referring to
2200 constructors/destructors.) */
2206 {
2209 }
2211 {
2215 }
2216 }
2218 /* Even if some of the member functions are non-private, the class
2219 won't be useful for much if all the constructors or destructors
2220 are private: such an object can never be created or destroyed. */
2223 {
2226 t);
2228 }
2230 /* Warn about classes that have private constructors and no friends. */
2232 /* Implicitly generated constructors are always public. */
2235 {
2238 /* If a non-template class does not define a copy
2239 constructor, one is defined for it, enabling it to avoid
2240 this warning. For a template class, this does not
2241 happen, and so we would normally get a warning on:
2243 template <class T> class C { private: C(); };
2245 To avoid this asymmetry, we check TYPE_HAS_COPY_CTOR. All
2246 complete non-template or fully instantiated classes have this
2247 flag set. */
2250 else
2253 /* Ideally, we wouldn't count copy constructors (or, in
2254 fact, any constructor that takes an argument of the class
2255 type as a parameter) because such things cannot be used
2256 to construct an instance of the class unless you already
2257 have one. But, for now at least, we're more
2258 generous. */
2263 {
2266 t);
2268 }
2269 }
2270 }
2273 gt_pointer_operator new_value;
2277 /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */
2279 static int
2281 {
2294 }
2296 /* This routine compares two fields like method_name_cmp but using the
2297 pointer operator in resort_field_decl_data. */
2299 static int
2301 {
2310 {
2317 }
2319 }
2321 /* Resort TYPE_METHOD_VEC because pointers have been reordered. */
2323 void
2326 gt_pointer_operator new_value,
2328 {
2332 tree fn;
2334 /* The type conversion ops have to live at the front of the vec, so we
2335 can't sort them. */
2343 {
2347 resort_method_name_cmp);
2348 }
2349 }
2351 /* Warn about duplicate methods in fn_fields.
2353 Sort methods that are not special (i.e., constructors, destructors,
2354 and type conversion operators) so that we can find them faster in
2355 search. */
2357 static void
2359 {
2360 tree fn_fields;
2370 /* Clear DECL_IN_AGGR_P for all functions. */
2375 /* Issue warnings about private constructors and such. If there are
2376 no methods, then some public defaults are generated. */
2379 /* The type conversion ops have to live at the front of the vec, so we
2380 can't sort them. */
2389 }
2391 /* Make BINFO's vtable have N entries, including RTTI entries,
2392 vbase and vcall offsets, etc. Set its type and call the back end
2393 to lay it out. */
2395 static void
2397 {
2398 tree atype;
2399 tree vtable;
2404 /* We may have to grow the vtable. */
2407 {
2411 }
2412 }
2414 /* True iff FNDECL and BASE_FNDECL (both non-static member functions)
2415 have the same signature. */
2417 int
2419 {
2420 /* One destructor overrides another if they are the same kind of
2421 destructor. */
2425 /* But a non-destructor never overrides a destructor, nor vice
2426 versa, nor do different kinds of destructors override
2427 one-another. For example, a complete object destructor does not
2428 override a deleting destructor. */
2437 {
2445 }
2447 }
2449 /* Returns TRUE if DERIVED is a binfo containing the binfo BASE as a
2450 subobject. */
2452 static bool
2454 {
2455 tree probe;
2458 {
2462 /* If we meet a virtual base, we can't follow the inheritance
2463 any more. See if the complete type of DERIVED contains
2464 such a virtual base. */
2467 }
2469 }
2472 /* The function for which we are trying to find a final overrider. */
2473 tree fn;
2474 /* The base class in which the function was declared. */
2475 tree declaring_base;
2476 /* The candidate overriders. */
2477 tree candidates;
2478 /* Path to most derived. */
2480 };
2482 /* Add the overrider along the current path to FFOD->CANDIDATES.
2483 Returns true if an overrider was found; false otherwise. */
2485 static bool
2489 {
2490 tree method;
2492 /* If BINFO is not the most derived type, try a more derived class.
2493 A definition there will overrider a definition here. */
2495 {
2496 depth--;
2500 }
2504 {
2507 /* Remove any candidates overridden by this new function. */
2509 {
2510 /* If *CANDIDATE overrides METHOD, then METHOD
2511 cannot override anything else on the list. */
2514 /* If METHOD overrides *CANDIDATE, remove *CANDIDATE. */
2517 else
2519 }
2521 /* Add the new function. */
2524 }
2527 }
2529 /* Called from find_final_overrider via dfs_walk. */
2531 static tree
2533 {
2541 }
2543 static tree
2545 {
2550 }
2552 /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for
2553 FN and whose TREE_VALUE is the binfo for the base where the
2554 overriding occurs. BINFO (in the hierarchy dominated by the binfo
2555 DERIVED) is the base object in which FN is declared. */
2557 static tree
2559 {
2560 find_final_overrider_data ffod;
2562 /* Getting this right is a little tricky. This is valid:
2564 struct S { virtual void f (); };
2565 struct T { virtual void f (); };
2566 struct U : public S, public T { };
2568 even though calling `f' in `U' is ambiguous. But,
2570 struct R { virtual void f(); };
2571 struct S : virtual public R { virtual void f (); };
2572 struct T : virtual public R { virtual void f (); };
2573 struct U : public S, public T { };
2575 is not -- there's no way to decide whether to put `S::f' or
2576 `T::f' in the vtable for `R'.
2578 The solution is to look at all paths to BINFO. If we find
2579 different overriders along any two, then there is a problem. */
2583 /* Determine the depth of the hierarchy. */
2594 /* If there was no winner, issue an error message. */
2599 }
2601 /* Return the index of the vcall offset for FN when TYPE is used as a
2602 virtual base. */
2604 static tree
2606 {
2608 tree_pair_p p;
2616 /* There should always be an appropriate index. */
2618 }
2620 /* Update an entry in the vtable for BINFO, which is in the hierarchy
2621 dominated by T. FN is the old function; VIRTUALS points to the
2622 corresponding position in the new BINFO_VIRTUALS list. IX is the index
2623 of that entry in the list. */
2625 static void
2628 {
2629 tree b;
2630 tree overrider;
2631 tree delta;
2632 tree virtual_base;
2633 tree first_defn;
2639 /* Find the nearest primary base (possibly binfo itself) which defines
2640 this function; this is the class the caller will convert to when
2641 calling FN through BINFO. */
2643 {
2648 /* The nearest definition is from a lost primary. */
2651 }
2654 /* Find the final overrider. */
2657 {
2660 }
2663 /* Check for adjusting covariant return types. */
2671 /* If the overrider is invalid, don't even try. */
2673 {
2674 /* If FN is a covariant thunk, we must figure out the adjustment
2675 to the final base FN was converting to. As OVERRIDER_TARGET might
2676 also be converting to the return type of FN, we have to
2677 combine the two conversions here. */
2684 {
2688 }
2689 else
2693 /* Find the equivalent binfo within the return type of the
2694 overriding function. We will want the vbase offset from
2695 there. */
2697 over_return);
2700 {
2701 /* There was no existing virtual thunk (which takes
2702 precedence). So find the binfo of the base function's
2703 return type within the overriding function's return type.
2704 Fortunately we know the covariancy is valid (it
2705 has already been checked), so we can just iterate along
2706 the binfos, which have been chained in inheritance graph
2707 order. Of course it is lame that we have to repeat the
2708 search here anyway -- we should really be caching pieces
2709 of the vtable and avoiding this repeated work. */
2712 /* Find the base binfo within the overriding function's
2713 return type. We will always find a thunk_binfo, except
2714 when the covariancy is invalid (which we will have
2715 already diagnosed). */
2718 thunk_binfo;
2724 /* See if virtual inheritance is involved. */
2726 virtual_offset;
2733 {
2737 {
2738 /* We convert via virtual base. Adjust the fixed
2739 offset to be from there. */
2740 offset =
2744 }
2746 /* There was an existing fixed offset, this must be
2747 from the base just converted to, and the base the
2748 FN was thunking to. */
2750 else
2752 }
2753 }
2756 /* Replace the overriding function with a covariant thunk. We
2757 will emit the overriding function in its own slot as
2758 well. */
2761 }
2762 else
2766 /* If we need a covariant thunk, then we may need to adjust first_defn.
2767 The ABI specifies that the thunks emitted with a function are
2768 determined by which bases the function overrides, so we need to be
2769 sure that we're using a thunk for some overridden base; even if we
2770 know that the necessary this adjustment is zero, there may not be an
2771 appropriate zero-this-adjustment thunk for us to use since thunks for
2772 overriding virtual bases always use the vcall offset.
2774 Furthermore, just choosing any base that overrides this function isn't
2775 quite right, as this slot won't be used for calls through a type that
2776 puts a covariant thunk here. Calling the function through such a type
2777 will use a different slot, and that slot is the one that determines
2778 the thunk emitted for that base.
2780 So, keep looking until we find the base that we're really overriding
2781 in this slot: the nearest primary base that doesn't use a covariant
2782 thunk in this slot. */
2784 {
2786 /* We already know that the overrider needs a covariant thunk. */
2789 {
2796 }
2798 }
2800 /* Assume that we will produce a thunk that convert all the way to
2801 the final overrider, and not to an intermediate virtual base. */
2804 /* See if we can convert to an intermediate virtual base first, and then
2805 use the vcall offset located there to finish the conversion. */
2807 {
2808 /* If we find the final overrider, then we can stop
2809 walking. */
2814 /* If we find a virtual base, and we haven't yet found the
2815 overrider, then there is a virtual base between the
2816 declaring base (first_defn) and the final overrider. */
2818 {
2821 }
2822 }
2824 /* Compute the constant adjustment to the `this' pointer. The
2825 `this' pointer, when this function is called, will point at BINFO
2826 (or one of its primary bases, which are at the same offset). */
2828 /* The `this' pointer needs to be adjusted from the declaration to
2829 the nearest virtual base. */
2834 /* If the nearest definition is in a lost primary, we don't need an
2835 entry in our vtable. Except possibly in a constructor vtable,
2836 if we happen to get our primary back. In that case, the offset
2837 will be zero, as it will be a primary base. */
2839 else
2840 /* The `this' pointer needs to be adjusted from pointing to
2841 BINFO to pointing at the base where the final overrider
2842 appears. */
2853 else
2857 }
2859 /* Called from modify_all_vtables via dfs_walk. */
2861 static tree
2863 {
2865 tree virtuals;
2866 tree old_virtuals;
2870 /* A base without a vtable needs no modification, and its bases
2871 are uninteresting. */
2876 /* Don't do the primary vtable, if it's new. */
2880 /* There's no need to modify the vtable for a non-virtual primary
2881 base; we're not going to use that vtable anyhow. We do still
2882 need to do this for virtual primary bases, as they could become
2883 non-primary in a construction vtable. */
2888 /* Now, go through each of the virtual functions in the virtual
2889 function table for BINFO. Find the final overrider, and update
2890 the BINFO_VIRTUALS list appropriately. */
2893 virtuals;
2897 binfo,
2902 }
2904 /* Update all of the primary and secondary vtables for T. Create new
2905 vtables as required, and initialize their RTTI information. Each
2906 of the functions in VIRTUALS is declared in T and may override a
2907 virtual function from a base class; find and modify the appropriate
2908 entries to point to the overriding functions. Returns a list, in
2909 declaration order, of the virtual functions that are declared in T,
2910 but do not appear in the primary base class vtable, and which
2911 should therefore be appended to the end of the vtable for T. */
2913 static tree
2915 {
2919 /* Mangle the vtable name before entering dfs_walk (c++/51884). */
2923 /* Update all of the vtables. */
2926 /* Add virtual functions not already in our primary vtable. These
2927 will be both those introduced by this class, and those overridden
2928 from secondary bases. It does not include virtuals merely
2929 inherited from secondary bases. */
2931 {
2936 {
2937 /* We don't need to adjust the `this' pointer when
2938 calling this function. */
2942 /* This is a function not already in our vtable. Keep it. */
2944 }
2945 else
2946 /* We've already got an entry for this function. Skip it. */
2948 }
2951 }
2953 /* Get the base virtual function declarations in T that have the
2954 indicated NAME. */
2956 static void
2958 {
2962 /* Find virtual functions in T with the indicated NAME. */
2967 {
2972 {
2975 }
2976 }
2982 {
2985 }
2986 }
2988 /* If this declaration supersedes the declaration of
2989 a method declared virtual in the base class, then
2990 mark this field as being virtual as well. */
2992 void
2994 {
2997 /* In [temp.mem] we have:
2999 A specialization of a member function template does not
3000 override a virtual function from a base class. */
3007 /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor
3008 the error_mark_node so that we know it is an overriding
3009 function. */
3010 {
3017 }
3020 {
3026 }
3031 }
3033 /* Warn about hidden virtual functions that are not overridden in t.
3034 We know that constructors and destructors don't apply. */
3036 static void
3038 {
3040 tree fns;
3043 /* We go through each separately named virtual function. */
3047 {
3048 tree fndecl;
3049 tree base_binfo;
3050 tree binfo;
3053 /* All functions in this slot in the CLASSTYPE_METHOD_VEC will
3054 have the same name. Figure out what name that is. */
3056 /* There are no possibly hidden functions yet. */
3058 /* Iterate through all of the base classes looking for possibly
3059 hidden functions. */
3062 {
3065 }
3067 /* If there are no functions to hide, continue. */
3071 /* Remove any overridden functions. */
3073 {
3077 {
3078 /* If the method from the base class has the same
3079 signature as the method from the derived class, it
3080 has been overridden. */
3085 }
3086 }
3088 /* Now give a warning for all base functions without overriders,
3089 as they are hidden. */
3091 tree base_fndecl;
3094 {
3095 /* Here we know it is a hider, and no overrider exists. */
3097 OPT_Woverloaded_virtual,
3101 }
3102 }
3103 }
3105 /* Recursive helper for finish_struct_anon. */
3107 static void
3109 {
3113 {
3114 /* We're generally only interested in entities the user
3115 declared, but we also find nested classes by noticing
3116 the TYPE_DECL that we create implicitly. You're
3117 allowed to put one anonymous union inside another,
3118 though, so we explicitly tolerate that. We use
3119 TYPE_UNNAMED_P rather than ANON_AGGR_TYPE_P so that
3120 we also allow unnamed types used for defining fields. */
3127 {
3128 /* We already complained about static data members in
3129 finish_static_data_member_decl. */
3131 {
3134 "%q#D invalid; an anonymous union can "
3136 else
3138 "%q#D invalid; an anonymous struct can "
3140 }
3142 }
3145 {
3147 {
3151 else
3154 }
3156 {
3160 else
3163 }
3164 }
3169 /* Recurse into the anonymous aggregates to handle correctly
3170 access control (c++/24926):
3172 class A {
3173 union {
3174 union {
3175 int i;
3176 };
3177 };
3178 };
3180 int j=A().i; */
3184 }
3185 }
3187 /* Check for things that are invalid. There are probably plenty of other
3188 things we should check for also. */
3190 static void
3192 {
3194 {
3203 }
3204 }
3206 /* Add T to CLASSTYPE_DECL_LIST of current_class_type which
3207 will be used later during class template instantiation.
3208 When FRIEND_P is zero, T can be a static member data (VAR_DECL),
3209 a non-static member data (FIELD_DECL), a member function
3210 (FUNCTION_DECL), a nested type (RECORD_TYPE, ENUM_TYPE),
3211 a typedef (TYPE_DECL) or a member class template (TEMPLATE_DECL)
3212 When FRIEND_P is nonzero, T is either a friend class
3213 (RECORD_TYPE, TEMPLATE_DECL) or a friend function
3214 (FUNCTION_DECL, TEMPLATE_DECL). */
3216 void
3218 {
3219 /* Save some memory by not creating TREE_LIST if TYPE is not template. */
3224 }
3226 /* This function is called from declare_virt_assop_and_dtor via
3227 dfs_walk_all.
3229 DATA is a type that direcly or indirectly inherits the base
3230 represented by BINFO. If BINFO contains a virtual assignment [copy
3231 assignment or move assigment] operator or a virtual constructor,
3232 declare that function in DATA if it hasn't been already declared. */
3234 static tree
3236 {
3244 /* A base without a vtable needs no modification, and its bases
3245 are uninteresting. */
3249 /* If this is a primary base, then we have already looked at the
3250 virtual functions of its vtable. */
3254 {
3258 {
3263 }
3267 }
3270 }
3272 /* If the class type T has a direct or indirect base that contains a
3273 virtual assignment operator or a virtual destructor, declare that
3274 function in T if it hasn't been already declared. */
3276 static void
3278 {
3286 dfs_declare_virt_assop_and_dtor,
3288 }
3290 /* Declare the inheriting constructor for class T inherited from base
3291 constructor CTOR with the parameter array PARMS of size NPARMS. */
3293 static void
3295 {
3296 /* We don't declare an inheriting ctor that would be a default,
3297 copy or move ctor for derived or base. */
3302 {
3306 }
3315 {
3318 }
3319 }
3321 /* Declare all the inheriting constructors for class T inherited from base
3322 constructor CTOR. */
3324 static void
3326 {
3330 {
3336 }
3341 {
3345 }
3348 {
3352 }
3353 }
3355 /* Create default constructors, assignment operators, and so forth for
3356 the type indicated by T, if they are needed. CANT_HAVE_CONST_CTOR,
3357 and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason,
3358 the class cannot have a default constructor, copy constructor
3359 taking a const reference argument, or an assignment operator taking
3360 a const reference, respectively. */
3362 static void
3366 {
3374 /* Destructor. */
3376 /* In general, we create destructors lazily. */
3379 /* [class.ctor]
3381 If there is no user-declared constructor for a class, a default
3382 constructor is implicitly declared. */
3384 {
3389 /* Don't force the declaration to get a hard answer; if the
3390 definition would have made the class non-literal, it will still be
3391 non-literal because of the base or member in question, and that
3392 gives a better diagnostic. */
3394 }
3396 /* [class.ctor]
3398 If a class definition does not explicitly declare a copy
3399 constructor, one is declared implicitly. */
3401 {
3407 }
3409 /* If there is no assignment operator, one will be created if and
3410 when it is needed. For now, just record whether or not the type
3411 of the parameter to the assignment operator will be a const or
3412 non-const reference. */
3414 {
3420 }
3422 /* We can't be lazy about declaring functions that might override
3423 a virtual function from a base class. */
3427 {
3431 {
3432 /* declare, then remove the decl */
3440 }
3441 else
3443 }
3444 }
3446 /* Subroutine of insert_into_classtype_sorted_fields. Recursively
3447 count the number of fields in TYPE, including anonymous union
3448 members. */
3450 static int
3452 {
3453 tree x;
3456 {
3459 else
3461 }
3463 }
3465 /* Subroutine of insert_into_classtype_sorted_fields. Recursively add
3466 all the fields in the TREE_LIST FIELDS to the SORTED_FIELDS_TYPE
3467 elts, starting at offset IDX. */
3469 static int
3471 {
3472 tree x;
3474 {
3477 else
3479 }
3481 }
3483 /* Add all of the enum values of ENUMTYPE, to the FIELD_VEC elts,
3484 starting at offset IDX. */
3486 static int
3490 {
3491 tree values;
3495 }
3497 /* FIELD is a bit-field. We are finishing the processing for its
3498 enclosing type. Issue any appropriate messages and set appropriate
3499 flags. Returns false if an error has been diagnosed. */
3501 static bool
3503 {
3505 tree w;
3507 /* Extract the declared width of the bitfield, which has been
3508 temporarily stashed in DECL_INITIAL. */
3511 /* Remove the bit-field width indicator so that the rest of the
3512 compiler does not treat that value as an initializer. */
3515 /* Detect invalid bit-field type. */
3517 {
3520 }
3521 else
3522 {
3524 /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */
3527 /* detect invalid field size. */
3533 {
3536 }
3538 {
3541 }
3543 {
3546 }
3561 }
3564 {
3568 }
3569 else
3570 {
3571 /* Non-bit-fields are aligned for their type. */
3575 }
3576 }
3578 /* FIELD is a non bit-field. We are finishing the processing for its
3579 enclosing type T. Issue any appropriate messages and set appropriate
3580 flags. */
3582 static bool
3584 tree t,
3587 {
3591 /* In C++98 an anonymous union cannot contain any fields which would change
3592 the settings of CANT_HAVE_CONST_CTOR and friends. */
3594 ;
3595 /* And, we don't set TYPE_HAS_CONST_COPY_CTOR, etc., for anonymous
3596 structs. So, we recurse through their fields here. */
3598 {
3603 cant_have_const_ctor,
3604 no_const_asn_ref);
3605 }
3606 /* Check members with class type for constructors, destructors,
3607 etc. */
3609 {
3610 /* Never let anything with uninheritable virtuals
3611 make it through without complaint. */
3615 {
3620 field);
3625 field);
3627 {
3631 }
3632 }
3633 else
3634 {
3647 }
3656 }
3661 /* `build_class_init_list' does not recognize
3662 non-FIELD_DECLs. */
3666 }
3668 /* Check the data members (both static and non-static), class-scoped
3669 typedefs, etc., appearing in the declaration of T. Issue
3670 appropriate diagnostics. Sets ACCESS_DECLS to a list (in
3671 declaration order) of access declarations; each TREE_VALUE in this
3672 list is a USING_DECL.
3674 In addition, set the following flags:
3676 EMPTY_P
3677 The class is empty, i.e., contains no non-static data members.
3679 CANT_HAVE_CONST_CTOR_P
3680 This class cannot have an implicitly generated copy constructor
3681 taking a const reference.
3683 CANT_HAVE_CONST_ASN_REF
3684 This class cannot have an implicitly generated assignment
3685 operator taking a const reference.
3687 All of these flags should be initialized before calling this
3688 function.
3690 Returns a pointer to the end of the TYPE_FIELDs chain; additional
3691 fields can be added by adding to this chain. */
3693 static void
3697 {
3705 /* Assume there are no access declarations. */
3707 /* Assume this class has no pointer members. */
3709 /* Assume none of the members of this class have default
3710 initializations. */
3714 {
3722 {
3723 /* Save the access declarations for our caller. */
3726 }
3732 /* If we've gotten this far, it's a data member, possibly static,
3733 or an enumerator. */
3737 /* When this goes into scope, it will be a non-local reference. */
3741 {
3742 /* [class.union] (C++98)
3744 If a union contains a static data member, or a member of
3745 reference type, the program is ill-formed.
3747 In C++11 [class.union] says:
3748 If a union contains a non-static data member of reference type
3749 the program is ill-formed. */
3751 {
3755 }
3758 {
3762 }
3763 }
3765 /* Perform error checking that did not get done in
3766 grokdeclarator. */
3768 {
3772 }
3774 {
3778 }
3786 /* Now it can only be a FIELD_DECL. */
3791 /* If at least one non-static data member is non-literal, the whole
3792 class becomes non-literal. Per Core/1453, volatile non-static
3793 data members and base classes are also not allowed.
3794 Note: if the type is incomplete we will complain later on. */
3799 /* A standard-layout class is a class that:
3800 ...
3801 has the same access control (Clause 11) for all non-static data members,
3802 ... */
3809 /* If this is of reference type, check if it needs an init. */
3811 {
3817 {
3818 /* ARM $12.6.2: [A member initializer list] (or, for an
3819 aggregate, initialization by a brace-enclosed list) is the
3820 only way to initialize nonstatic const and reference
3821 members. */
3824 }
3825 }
3830 {
3832 {
3833 warning_at
3836 x);
3838 }
3842 }
3845 /* We don't treat zero-width bitfields as making a class
3846 non-empty. */
3847 ;
3848 else
3849 {
3850 /* The class is non-empty. */
3852 /* The class is not even nearly empty. */
3854 /* If one of the data members contains an empty class,
3855 so does T. */
3859 }
3861 /* This is used by -Weffc++ (see below). Warn only for pointers
3862 to members which might hold dynamic memory. So do not warn
3863 for pointers to functions or pointers to members. */
3869 {
3874 }
3880 {
3882 {
3886 }
3888 {
3892 }
3893 }
3896 /* DR 148 now allows pointers to members (which are POD themselves),
3897 to be allowed in POD structs. */
3906 /* We set DECL_C_BIT_FIELD in grokbitfield.
3907 If the type and width are valid, we'll also set DECL_BIT_FIELD. */
3910 cant_have_const_ctor_p,
3911 no_const_asn_ref_p))
3912 {
3917 }
3919 /* Now that we've removed bit-field widths from DECL_INITIAL,
3920 anything left in DECL_INITIAL is an NSDMI that makes the class
3921 non-aggregate in C++11. */
3925 /* If any field is const, the structure type is pseudo-const. */
3927 {
3932 {
3933 /* ARM $12.6.2: [A member initializer list] (or, for an
3934 aggregate, initialization by a brace-enclosed list) is the
3935 only way to initialize nonstatic const and reference
3936 members. */
3939 }
3940 }
3941 /* A field that is pseudo-const makes the structure likewise. */
3943 {
3948 }
3950 /* Core issue 80: A nonstatic data member is required to have a
3951 different name from the class iff the class has a
3952 user-declared constructor. */
3957 }
3959 /* Effective C++ rule 11: if a class has dynamic memory held by pointers,
3960 it should also define a copy constructor and an assignment operator to
3961 implement the correct copy semantic (deep vs shallow, etc.). As it is
3962 not feasible to check whether the constructors do allocate dynamic memory
3963 and store it within members, we approximate the warning like this:
3965 -- Warn only if there are members which are pointers
3966 -- Warn only if there is a non-trivial constructor (otherwise,
3967 there cannot be memory allocated).
3968 -- Warn only if there is a non-trivial destructor. We assume that the
3969 user at least implemented the cleanup correctly, and a destructor
3970 is needed to free dynamic memory.
3972 This seems enough for practical purposes. */
3974 && has_pointers
3978 {
3982 {
3987 }
3991 }
3993 /* Non-static data member initializers make the default constructor
3994 non-trivial. */
3996 {
3999 }
4001 /* If any of the fields couldn't be packed, unset TYPE_PACKED. */
4005 /* Check anonymous struct/anonymous union fields. */
4008 /* We've built up the list of access declarations in reverse order.
4009 Fix that now. */
4011 }
4013 /* If TYPE is an empty class type, records its OFFSET in the table of
4014 OFFSETS. */
4016 static int
4018 {
4019 splay_tree_node n;
4024 /* Record the location of this empty object in OFFSETS. */
4032 type,
4036 }
4038 /* Returns nonzero if TYPE is an empty class type and there is
4039 already an entry in OFFSETS for the same TYPE as the same OFFSET. */
4041 static int
4043 {
4044 splay_tree_node n;
4045 tree t;
4050 /* Record the location of this empty object in OFFSETS. */
4060 }
4062 /* Walk through all the subobjects of TYPE (located at OFFSET). Call
4063 F for every subobject, passing it the type, offset, and table of
4064 OFFSETS. If VBASES_P is one, then virtual non-primary bases should
4065 be traversed.
4067 If MAX_OFFSET is non-NULL, then subobjects with an offset greater
4068 than MAX_OFFSET will not be walked.
4070 If F returns a nonzero value, the traversal ceases, and that value
4071 is returned. Otherwise, returns zero. */
4073 static int
4075 subobject_offset_fn f,
4076 tree offset,
4077 splay_tree offsets,
4078 tree max_offset,
4080 {
4084 /* If this OFFSET is bigger than the MAX_OFFSET, then we should
4085 stop. */
4093 {
4096 }
4099 {
4100 tree field;
4101 tree binfo;
4104 /* Avoid recursing into objects that are not interesting. */
4108 /* Record the location of TYPE. */
4113 /* Iterate through the direct base classes of TYPE. */
4117 {
4118 tree binfo_offset;
4123 tree orig_binfo;
4124 /* We cannot rely on BINFO_OFFSET being set for the base
4125 class yet, but the offsets for direct non-virtual
4126 bases can be calculated by going back to the TYPE. */
4129 offset,
4133 f,
4134 binfo_offset,
4135 offsets,
4136 max_offset,
4140 }
4143 {
4147 /* Iterate through the virtual base classes of TYPE. In G++
4148 3.2, we included virtual bases in the direct base class
4149 loop above, which results in incorrect results; the
4150 correct offsets for virtual bases are only known when
4151 working with the most derived type. */
4155 {
4157 f,
4159 offset,
4161 offsets,
4162 max_offset,
4166 }
4167 else
4168 {
4169 /* We still have to walk the primary base, if it is
4170 virtual. (If it is non-virtual, then it was walked
4171 above.) */
4177 {
4178 r = (walk_subobject_offsets
4183 }
4184 }
4185 }
4187 /* Iterate through the fields of TYPE. */
4192 {
4193 tree field_offset;
4198 f,
4200 offset,
4201 field_offset),
4202 offsets,
4203 max_offset,
4207 }
4208 }
4210 {
4213 tree index;
4215 /* Avoid recursing into objects that are not interesting. */
4218 || !domain
4222 /* Step through each of the elements in the array. */
4226 {
4228 f,
4229 offset,
4230 offsets,
4231 max_offset,
4237 /* If this new OFFSET is bigger than the MAX_OFFSET, then
4238 there's no point in iterating through the remaining
4239 elements of the array. */
4242 }
4243 }
4246 }
4248 /* Record all of the empty subobjects of TYPE (either a type or a
4249 binfo). If IS_DATA_MEMBER is true, then a non-static data member
4250 is being placed at OFFSET; otherwise, it is a base class that is
4251 being placed at OFFSET. */
4253 static void
4255 tree offset,
4256 splay_tree offsets,
4258 {
4259 tree max_offset;
4260 /* If recording subobjects for a non-static data member or a
4261 non-empty base class , we do not need to record offsets beyond
4262 the size of the biggest empty class. Additional data members
4263 will go at the end of the class. Additional base classes will go
4264 either at offset zero (if empty, in which case they cannot
4265 overlap with offsets past the size of the biggest empty class) or
4266 at the end of the class.
4268 However, if we are placing an empty base class, then we must record
4269 all offsets, as either the empty class is at offset zero (where
4270 other empty classes might later be placed) or at the end of the
4271 class (where other objects might then be placed, so other empty
4272 subobjects might later overlap). */
4276 else
4280 }
4282 /* Returns nonzero if any of the empty subobjects of TYPE (located at
4283 OFFSET) conflict with entries in OFFSETS. If VBASES_P is nonzero,
4284 virtual bases of TYPE are examined. */
4286 static int
4288 tree offset,
4289 splay_tree offsets,
4291 {
4292 splay_tree_node max_node;
4294 /* Get the node in OFFSETS that indicates the maximum offset where
4295 an empty subobject is located. */
4297 /* If there aren't any empty subobjects, then there's no point in
4298 performing this check. */
4304 vbases_p);
4305 }
4307 /* DECL is a FIELD_DECL corresponding either to a base subobject of a
4308 non-static data member of the type indicated by RLI. BINFO is the
4309 binfo corresponding to the base subobject, OFFSETS maps offsets to
4310 types already located at those offsets. This function determines
4311 the position of the DECL. */
4313 static void
4315 tree decl,
4316 tree binfo,
4317 splay_tree offsets)
4318 {
4321 tree type;
4324 {
4325 /* For the purposes of determining layout conflicts, we want to
4326 use the class type of BINFO; TREE_TYPE (DECL) will be the
4327 CLASSTYPE_AS_BASE version, which does not contain entries for
4328 zero-sized bases. */
4331 }
4332 else
4333 {
4336 }
4338 /* Try to place the field. It may take more than one try if we have
4339 a hard time placing the field without putting two objects of the
4340 same type at the same address. */
4342 {
4345 /* Place this field. */
4349 /* We have to check to see whether or not there is already
4350 something of the same type at the offset we're about to use.
4351 For example, consider:
4353 struct S {};
4354 struct T : public S { int i; };
4355 struct U : public S, public T {};
4357 Here, we put S at offset zero in U. Then, we can't put T at
4358 offset zero -- its S component would be at the same address
4359 as the S we already allocated. So, we have to skip ahead.
4360 Since all data members, including those whose type is an
4361 empty class, have nonzero size, any overlap can happen only
4362 with a direct or indirect base-class -- it can't happen with
4363 a data member. */
4364 /* In a union, overlap is permitted; all members are placed at
4365 offset zero. */
4370 {
4371 /* Strip off the size allocated to this field. That puts us
4372 at the first place we could have put the field with
4373 proper alignment. */
4376 /* Bump up by the alignment required for the type. */
4377 rli->bitpos
4383 }
4386 {
4387 /* Before ABI v9, we were giving nullptr_t alignment of 1; if
4388 the offset wasn't aligned like a pointer when we started to
4389 layout this field, that affects its position. */
4392 {
4395 "alignment of %qD increased in -fabi-version=9 "
4397 else
4400 }
4402 }
4403 else
4404 /* There was no conflict. We're done laying out this field. */
4406 }
4408 /* Now that we know where it will be placed, update its
4409 BINFO_OFFSET. */
4411 /* Indirect virtual bases may have a nonzero BINFO_OFFSET at
4412 this point because their BINFO_OFFSET is copied from another
4413 hierarchy. Therefore, we may not need to add the entire
4414 OFFSET. */
4420 }
4422 /* Returns true if TYPE is empty and OFFSET is nonzero. */
4424 static int
4426 tree offset,
4428 {
4430 }
4432 /* Layout the empty base BINFO. EOC indicates the byte currently just
4433 past the end of the class, and should be correctly aligned for a
4434 class of the type indicated by BINFO; OFFSETS gives the offsets of
4435 the empty bases allocated so far. T is the most derived
4436 type. Return nonzero iff we added it at the end. */
4438 static bool
4441 {
4442 tree alignment;
4446 /* This routine should only be used for empty classes. */
4451 propagate_binfo_offsets
4455 /* This is an empty base class. We first try to put it at offset
4456 zero. */
4459 offsets,
4461 {
4462 /* That didn't work. Now, we move forward from the next
4463 available spot in the class. */
4467 {
4470 offsets,
4472 /* We finally found a spot where there's no overlap. */
4475 /* There's overlap here, too. Bump along to the next spot. */
4477 }
4478 }
4481 {
4486 }
4489 }
4491 /* Build the FIELD_DECL for BASETYPE as a base of T, add it to the chain of
4492 fields at NEXT_FIELD, and return it. */
4494 static tree
4496 {
4497 /* Create the FIELD_DECL. */
4511 /* Add the new FIELD_DECL to the list of fields for T. */
4517 }
4519 /* Layout the base given by BINFO in the class indicated by RLI.
4520 *BASE_ALIGN is a running maximum of the alignments of
4521 any base class. OFFSETS gives the location of empty base
4522 subobjects. T is the most derived type. Return nonzero if the new
4523 object cannot be nearly-empty. A new FIELD_DECL is inserted at
4524 *NEXT_FIELD, unless BINFO is for an empty base class.
4526 Returns the location at which the next field should be inserted. */
4531 {
4536 /* This error is now reported in xref_tag, thus giving better
4537 location information. */
4540 /* Place the base class. */
4542 {
4543 tree decl;
4545 /* The containing class is non-empty because it has a non-empty
4546 base class. */
4549 /* Create the FIELD_DECL. */
4552 /* Try to place the field. It may take more than one try if we
4553 have a hard time placing the field without putting two
4554 objects of the same type at the same address. */
4556 }
4557 else
4558 {
4559 tree eoc;
4562 /* On some platforms (ARM), even empty classes will not be
4563 byte-aligned. */
4568 /* A nearly-empty class "has no proper base class that is empty,
4569 not morally virtual, and at an offset other than zero." */
4571 {
4574 /* The check above (used in G++ 3.2) is insufficient because
4575 an empty class placed at offset zero might itself have an
4576 empty base at a nonzero offset. */
4578 empty_base_at_nonzero_offset_p,
4579 size_zero_node,
4584 }
4586 /* We used to not create a FIELD_DECL for empty base classes because of
4587 back end issues with overlapping FIELD_DECLs, but that doesn't seem to
4588 be a problem anymore. We need them to handle initialization of C++17
4589 aggregate bases. */
4591 {
4596 }
4598 /* An empty virtual base causes a class to be non-empty
4599 -- but in that case we do not need to clear CLASSTYPE_EMPTY_P
4600 here because that was already done when the virtual table
4601 pointer was created. */
4602 }
4604 /* Record the offsets of BINFO and its base subobjects. */
4607 offsets,
4611 }
4613 /* Layout all of the non-virtual base classes. Record empty
4614 subobjects in OFFSETS. T is the most derived type. Return nonzero
4615 if the type cannot be nearly empty. The fields created
4616 corresponding to the base classes will be inserted at
4617 *NEXT_FIELD. */
4619 static void
4622 {
4623 /* Chain to hold all the new FIELD_DECLs which stand in for base class
4624 subobjects. */
4629 /* The primary base class is always allocated first. */
4634 /* Now allocate the rest of the bases. */
4636 {
4637 tree base_binfo;
4641 /* The primary base was already allocated above, so we don't
4642 need to allocate it again here. */
4646 /* Virtual bases are added at the end (a primary virtual base
4647 will have already been added). */
4653 }
4654 }
4656 /* Go through the TYPE_METHODS of T issuing any appropriate
4657 diagnostics, figuring out which methods override which other
4658 methods, and so forth. */
4660 static void
4662 {
4663 tree x;
4666 {
4670 /* The name of the field is the original field name
4671 Save this in auxiliary field for later overloading. */
4673 {
4677 }
4678 /* All user-provided destructors are non-trivial.
4679 Constructors and assignment ops are handled in
4680 grok_special_member_properties. */
4686 "%<transaction_safe_dynamic%> may only be specified for "
4688 }
4689 }
4691 /* FN is a constructor or destructor. Clone the declaration to create
4692 a specialized in-charge or not-in-charge version, as indicated by
4693 NAME. */
4695 static tree
4697 {
4698 tree parms;
4699 tree clone;
4701 /* Copy the function. */
4703 /* Reset the function name. */
4705 /* Remember where this function came from. */
4707 /* Make it easy to find the CLONE given the FN. */
4711 /* If this is a template, do the rest on the DECL_TEMPLATE_RESULT. */
4713 {
4720 }
4721 else
4722 {
4723 // Clone constraints.
4727 }
4732 /* There's no pending inline data for this function. */
4736 /* The base-class destructor is not virtual. */
4738 {
4742 }
4748 /* If there was an in-charge parameter, drop it from the function
4749 type. */
4751 {
4752 tree basetype;
4753 tree parmtypes;
4754 tree exceptions;
4759 /* Skip the `this' parameter. */
4761 /* Skip the in-charge parameter. */
4763 /* And the VTT parm, in a complete [cd]tor. */
4768 {
4769 /* If we're omitting inherited parms, that just leaves the VTT. */
4772 }
4776 parmtypes);
4779 exceptions);
4783 }
4785 /* Copy the function parameters. */
4787 /* Remove the in-charge parameter. */
4789 {
4793 }
4794 /* And the VTT parm, in a complete [cd]tor. */
4796 {
4799 else
4800 {
4804 }
4805 }
4807 /* A base constructor inheriting from a virtual base doesn't get the
4808 arguments. */
4813 {
4816 }
4818 /* Create the RTL for this function. */
4823 }
4825 /* Implementation of DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P, do
4826 not invoke this function directly.
4828 For a non-thunk function, returns the address of the slot for storing
4829 the function it is a clone of. Otherwise returns NULL_TREE.
4831 If JUST_TESTING, looks through TEMPLATE_DECL and returns NULL if
4832 cloned_function is unset. This is to support the separate
4833 DECL_CLONED_FUNCTION and DECL_CLONED_FUNCTION_P modes; using the latter
4834 on a template makes sense, but not the former. */
4836 tree *
4838 {
4846 {
4847 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
4850 else
4851 #endif
4853 }
4858 else
4860 }
4862 /* Produce declarations for all appropriate clones of FN. If
4863 UPDATE_METHODS is true, the clones are added to the
4864 CLASSTYPE_METHOD_VEC. */
4866 void
4868 {
4869 tree clone;
4871 /* Avoid inappropriate cloning. */
4877 {
4878 /* For each constructor, we need two variants: an in-charge version
4879 and a not-in-charge version. */
4886 }
4887 else
4888 {
4891 /* For each destructor, we need three variants: an in-charge
4892 version, a not-in-charge version, and an in-charge deleting
4893 version. We clone the deleting version first because that
4894 means it will go second on the TYPE_METHODS list -- and that
4895 corresponds to the correct layout order in the virtual
4896 function table.
4898 For a non-virtual destructor, we do not build a deleting
4899 destructor. */
4901 {
4905 }
4912 }
4914 /* Note that this is an abstract function that is never emitted. */
4916 }
4918 /* DECL is an in charge constructor, which is being defined. This will
4919 have had an in class declaration, from whence clones were
4920 declared. An out-of-class definition can specify additional default
4921 arguments. As it is the clones that are involved in overload
4922 resolution, we must propagate the information from the DECL to its
4923 clones. */
4925 void
4927 {
4928 tree clone;
4932 {
4939 /* Skip the 'this' parameter. */
4955 {
4957 {
4961 }
4967 {
4968 /* A default parameter has been added. Adjust the
4969 clone's parameters. */
4973 tree type;
4978 {
4981 clone_parms);
4983 }
4986 clone_parms);
4995 }
4996 }
4998 }
4999 }
5001 /* For each of the constructors and destructors in T, create an
5002 in-charge and not-in-charge variant. */
5004 static void
5006 {
5007 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
5008 out now. */
5012 /* While constructors can be via a using declaration, at this point
5013 we no longer need to know that. */
5018 }
5020 /* Deduce noexcept for a destructor DTOR. */
5022 void
5024 {
5026 {
5029 }
5030 }
5032 /* For each destructor in T, deduce noexcept:
5034 12.4/3: A declaration of a destructor that does not have an
5035 exception-specification is implicitly considered to have the
5036 same exception-specification as an implicit declaration (15.4). */
5038 static void
5040 {
5041 /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail
5042 out now. */
5048 }
5050 /* Subroutine of set_one_vmethod_tm_attributes. Search base classes
5051 of TYPE for virtual functions which FNDECL overrides. Return a
5052 mask of the tm attributes found therein. */
5054 static int
5056 {
5058 tree base_binfo;
5062 {
5070 {
5074 else
5077 }
5078 else
5080 }
5083 }
5085 /* Subroutine of set_method_tm_attributes. Handle the checks and
5086 inheritance for one virtual method FNDECL. */
5088 static void
5090 {
5091 tree tm_attr;
5096 /* If FNDECL doesn't actually override anything (i.e. T is the
5097 class that first declares FNDECL virtual), then we're done. */
5104 /* Intel STM Language Extension 3.0, Section 4.2 table 4:
5105 tm_pure must match exactly, otherwise no weakening of
5106 tm_safe > tm_callable > nothing. */
5107 /* ??? The tm_pure attribute didn't make the transition to the
5108 multivendor language spec. */
5110 {
5112 {
5115 }
5116 }
5117 /* If the overridden function is tm_pure, then FNDECL must be. */
5120 /* Look for base class combinations that cannot be satisfied. */
5122 {
5128 }
5129 /* If FNDECL did not declare an attribute, then inherit the most
5130 restrictive one. */
5132 {
5134 }
5135 /* Otherwise validate that we're not weaker than a function
5136 that is being overridden. */
5137 else
5138 {
5142 }
5145 err_override:
5149 }
5151 /* For each of the methods in T, propagate a class-level tm attribute. */
5153 static void
5155 {
5158 /* Don't bother collecting tm attributes if transactional memory
5159 support is not enabled. */
5163 /* Process virtual methods first, as they inherit directly from the
5164 base virtual function and also require validation of new attributes. */
5166 {
5167 tree vchain;
5170 {
5175 }
5176 }
5178 /* If the class doesn't have an attribute, nothing more to do. */
5183 /* Any method that does not yet have a tm attribute inherits
5184 the one from the class. */
5186 {
5189 }
5190 }
5192 /* Returns true if FN is a default constructor. */
5194 bool
5196 {
5199 }
5201 /* Returns true iff class T has a user-defined constructor that can be called
5202 with more than zero arguments. */
5204 bool
5206 {
5211 {
5218 }
5221 }
5223 /* Returns the defaulted constructor if T has one. Otherwise, returns
5224 NULL_TREE. */
5226 tree
5228 {
5233 {
5239 }
5242 }
5244 /* Returns true iff FN is a user-provided function, i.e. user-declared
5245 and not defaulted at its first declaration. */
5247 bool
5249 {
5252 else
5256 }
5258 /* Returns true iff class T has a user-provided constructor. */
5260 bool
5262 {
5269 /* This can happen in error cases; avoid crashing. */
5278 }
5280 /* Returns true iff class T has a user-provided or explicit constructor. */
5282 bool
5284 {
5291 /* This can happen in error cases; avoid crashing. */
5296 {
5300 }
5303 }
5305 /* Returns true iff class T has a non-user-provided (i.e. implicitly
5306 declared or explicitly defaulted in the class body) default
5307 constructor. */
5309 bool
5311 {
5318 {
5324 }
5327 }
5329 /* TYPE is being used as a virtual base, and has a non-trivial move
5330 assignment. Return true if this is due to there being a user-provided
5331 move assignment in TYPE or one of its subobjects; if there isn't, then
5332 multiple move assignment can't cause any harm. */
5334 bool
5336 {
5337 /* Does the type itself have a user-provided move assignment operator? */
5341 {
5345 }
5347 /* Do any of its bases? */
5349 tree base_binfo;
5354 /* Or non-static data members? */
5356 {
5361 }
5363 /* Seems not. */
5365 }
5367 /* If default-initialization leaves part of TYPE uninitialized, returns
5368 a DECL for the field or TYPE itself (DR 253). */
5370 tree
5372 {
5383 {
5387 }
5392 {
5396 }
5399 }
5401 /* Returns true iff for class T, a trivial synthesized default constructor
5402 would be constexpr. */
5404 bool
5406 {
5407 /* A defaulted trivial default constructor is constexpr
5408 if there is nothing to initialize. */
5411 }
5413 /* Returns true iff class T has a constexpr default constructor. */
5415 bool
5417 {
5418 tree fns;
5421 {
5422 /* The caller should have stripped an enclosing array. */
5425 }
5427 {
5430 /* Non-trivial, we need to check subobject constructors. */
5432 }
5435 }
5437 /* Returns true iff class T has a constexpr default constructor or has an
5438 implicitly declared default constructor that we can't tell if it's constexpr
5439 without forcing a lazy declaration (which might cause undesired
5440 instantiations). */
5442 bool
5444 {
5447 /* Assume it's constexpr. */
5450 }
5452 /* Returns true iff class TYPE has a virtual destructor. */
5454 bool
5456 {
5457 tree dtor;
5465 }
5467 /* Returns true iff class T has a move constructor. */
5469 bool
5471 {
5473 {
5476 }
5486 }
5488 /* Returns true iff class T has a move assignment operator. */
5490 bool
5492 {
5494 {
5497 }
5506 }
5508 /* Returns true iff class T has a move constructor that was explicitly
5509 declared in the class body. Note that this is different from
5510 "user-provided", which doesn't include functions that are defaulted in
5511 the class. */
5513 bool
5515 {
5523 {
5527 }
5530 }
5532 /* Returns true iff class T has a move assignment operator that was
5533 explicitly declared in the class body. */
5535 bool
5537 {
5544 {
5548 }
5551 }
5553 /* Nonzero if we need to build up a constructor call when initializing an
5554 object of this class, either because it has a user-declared constructor
5555 or because it doesn't have a default constructor (so we need to give an
5556 error if no initializer is provided). Use TYPE_NEEDS_CONSTRUCTING when
5557 what you care about is whether or not an object can be produced by a
5558 constructor (e.g. so we don't set TREE_READONLY on const variables of
5559 such type); use this function when what you care about is whether or not
5560 to try to call a constructor to create an object. The latter case is
5561 the former plus some cases of constructors that cannot be called. */
5563 bool
5565 {
5566 tree inner;
5576 /* A user-declared constructor might be private, and a constructor might
5577 be trivial but deleted. */
5581 {
5586 }
5588 }
5590 /* Like type_build_ctor_call, but for destructors. */
5592 bool
5594 {
5595 tree inner;
5604 /* A user-declared destructor might be private, and a destructor might
5605 be trivial but deleted. */
5609 {
5614 }
5616 }
5618 /* Remove all zero-width bit-fields from T. */
5620 static void
5622 {
5627 {
5630 /* We should not be confused by the fact that grokbitfield
5631 temporarily sets the width of the bit field into
5632 DECL_INITIAL (*fieldsp).
5633 check_bitfield_decl eventually sets DECL_SIZE (*fieldsp)
5634 to that width. */
5638 else
5640 }
5641 }
5643 /* Returns TRUE iff we need a cookie when dynamically allocating an
5644 array whose elements have the indicated class TYPE. */
5646 static bool
5648 {
5649 tree fns;
5654 /* If there's a non-trivial destructor, we need a cookie. In order
5655 to iterate through the array calling the destructor for each
5656 element, we'll have to know how many elements there are. */
5660 /* If the usual deallocation function is a two-argument whose second
5661 argument is of type `size_t', then we have to pass the size of
5662 the array to the deallocation function, so we will need to store
5663 a cookie. */
5667 /* If there are no `operator []' members, or the lookup is
5668 ambiguous, then we don't need a cookie. */
5671 /* Loop through all of the functions. */
5673 {
5676 /* See if this function is a one-argument delete function. If
5677 it is, then it will be the usual deallocation function. */
5681 /* Do not consider this function if its second argument is an
5682 ellipsis. */
5685 /* Otherwise, if we have a two-argument function and the second
5686 argument is `size_t', it will be the usual deallocation
5687 function -- unless there is one-argument function, too. */
5691 }
5694 }
5696 /* Finish computing the `literal type' property of class type T.
5698 At this point, we have already processed base classes and
5699 non-static data members. We need to check whether the copy
5700 constructor is trivial, the destructor is trivial, and there
5701 is a trivial default constructor or at least one constexpr
5702 constructor other than the copy constructor. */
5704 static void
5706 {
5707 tree fn;
5719 /* C++14 DR 1684 removed this restriction. */
5727 {
5731 "enclosing class of constexpr non-static member "
5734 }
5735 }
5737 /* T is a non-literal type used in a context which requires a constant
5738 expression. Explain why it isn't literal. */
5740 void
5742 {
5752 /* Already explained. */
5765 {
5767 "default constructor, and has no constexpr constructor that "
5770 /* Note that we can't simply call locate_ctor because when the
5771 constructor is deleted it just returns NULL_TREE. */
5773 {
5780 {
5783 else
5786 }
5787 }
5788 }
5789 else
5790 {
5794 {
5797 {
5802 }
5803 }
5805 {
5806 tree ftype;
5811 {
5814 field);
5817 }
5821 }
5822 }
5823 }
5825 /* Check the validity of the bases and members declared in T. Add any
5826 implicitly-generated functions (like copy-constructors and
5827 assignment operators). Compute various flag bits (like
5828 CLASSTYPE_NON_LAYOUT_POD_T) for T. This routine works purely at the C++
5829 level: i.e., independently of the ABI in use. */
5831 static void
5833 {
5834 /* Nonzero if the implicitly generated copy constructor should take
5835 a non-const reference argument. */
5837 /* Nonzero if the implicitly generated assignment operator
5838 should take a non-const reference argument. */
5840 tree access_decls;
5843 tree fn;
5845 /* By default, we use const reference arguments and generate default
5846 constructors. */
5850 /* Check all the base-classes and set FMEM members to point to arrays
5851 of potential interest. */
5854 /* Deduce noexcept on destructors. This needs to happen after we've set
5855 triviality flags appropriately for our bases. */
5859 /* Check all the method declarations. */
5862 /* Save the initial values of these flags which only indicate whether
5863 or not the class has user-provided functions. As we analyze the
5864 bases and members we can set these flags for other reasons. */
5868 /* Check all the data member declarations. We cannot call
5869 check_field_decls until we have called check_bases check_methods,
5870 as check_field_decls depends on TYPE_HAS_NONTRIVIAL_DESTRUCTOR
5871 being set appropriately. */
5876 /* A nearly-empty class has to be vptr-containing; a nearly empty
5877 class contains just a vptr. */
5881 /* Do some bookkeeping that will guide the generation of implicitly
5882 declared member functions. */
5885 /* We need to call a constructor for this class if it has a
5886 user-provided constructor, or if the default constructor is going
5887 to initialize the vptr. (This is not an if-and-only-if;
5888 TYPE_NEEDS_CONSTRUCTING is set elsewhere if bases or members
5889 themselves need constructing.) */
5892 /* [dcl.init.aggr]
5894 An aggregate is an array or a class with no user-provided
5895 constructors ... and no virtual functions.
5897 Again, other conditions for being an aggregate are checked
5898 elsewhere. */
5902 /* This is the C++98/03 definition of POD; it changed in C++0x, but we
5903 retain the old definition internally for ABI reasons. */
5912 /* If the only explicitly declared default constructor is user-provided,
5913 set TYPE_HAS_COMPLEX_DFLT. */
5919 /* Warn if a public base of a polymorphic type has an accessible
5920 non-virtual destructor. It is only now that we know the class is
5921 polymorphic. Although a polymorphic base will have a already
5922 been diagnosed during its definition, we warn on use too. */
5924 {
5927 tree base_binfo;
5931 {
5939 basetype);
5940 }
5941 }
5943 /* If the class has no user-declared constructor, but does have
5944 non-static const or reference data members that can never be
5945 initialized, issue a warning. */
5947 /* Classes with user-declared constructors are presumed to
5948 initialize these members. */
5950 /* Aggregates can be initialized with brace-enclosed
5951 initializers. */
5953 {
5954 tree field;
5957 {
5958 tree type;
5975 }
5976 }
5978 /* Synthesize any needed methods. */
5980 cant_have_const_ctor,
5981 no_const_asn_ref);
5983 /* Check defaulted declarations here so we have cant_have_const_ctor
5984 and don't need to worry about clones. */
5987 {
5990 {
5991 bool imp_const_p
5997 /* If the function is defaulted outside the class, we just
5998 give the synthesis error. */
6001 }
6003 }
6006 {
6007 /* "This class type is not an aggregate." */
6009 }
6011 /* Compute the 'literal type' property before we
6012 do anything with non-static member functions. */
6015 /* Create the in-charge and not-in-charge variants of constructors
6016 and destructors. */
6019 /* Process the using-declarations. */
6023 /* Build and sort the CLASSTYPE_METHOD_VEC. */
6026 /* Figure out whether or not we will need a cookie when dynamically
6027 allocating an array of this type. */
6030 }
6032 /* If T needs a pointer to its virtual function table, set TYPE_VFIELD
6033 accordingly. If a new vfield was created (because T doesn't have a
6034 primary base class), then the newly created field is returned. It
6035 is not added to the TYPE_FIELDS list; it is the caller's
6036 responsibility to do that. Accumulate declared virtual functions
6037 on VIRTUALS_P. */
6039 static tree
6041 {
6042 tree fn;
6044 /* Collect the virtual functions declared in T. */
6049 {
6058 }
6060 /* If we couldn't find an appropriate base class, create a new field
6061 here. Even if there weren't any new virtual functions, we might need a
6062 new virtual function table if we're supposed to include vptrs in
6063 all classes that need them. */
6065 {
6066 /* We build this decl with vtbl_ptr_type_node, which is a
6067 `vtable_entry_type*'. It might seem more precise to use
6068 `vtable_entry_type (*)[N]' where N is the number of virtual
6069 functions. However, that would require the vtable pointer in
6070 base classes to have a different type than the vtable pointer
6071 in derived classes. We could make that happen, but that
6072 still wouldn't solve all the problems. In particular, the
6073 type-based alias analysis code would decide that assignments
6074 to the base class vtable pointer can't alias assignments to
6075 the derived class vtable pointer, since they have different
6076 types. Thus, in a derived class destructor, where the base
6077 class constructor was inlined, we could generate bad code for
6078 setting up the vtable pointer.
6080 Therefore, we use one type for all vtable pointers. We still
6081 use a type-correct type; it's just doesn't indicate the array
6082 bounds. That's better than using `void*' or some such; it's
6083 cleaner, and it let's the alias analysis code know that these
6084 stores cannot alias stores to void*! */
6085 tree field;
6098 /* This class is non-empty. */
6102 }
6105 }
6107 /* Add OFFSET to all base types of BINFO which is a base in the
6108 hierarchy dominated by T.
6110 OFFSET, which is a type offset, is number of bytes. */
6112 static void
6114 {
6116 tree primary_binfo;
6117 tree base_binfo;
6119 /* Update BINFO's offset. */
6124 offset));
6126 /* Find the primary base class. */
6132 /* Scan all of the bases, pushing the BINFO_OFFSET adjust
6133 downwards. */
6135 {
6136 /* Don't do the primary base twice. */
6144 }
6145 }
6147 /* Set BINFO_OFFSET for all of the virtual bases for RLI->T. Update
6148 TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of
6149 empty subobjects of T. */
6151 static void
6153 {
6154 tree vbase;
6161 /* Find the last field. The artificial fields created for virtual
6162 bases will go after the last extant field to date. */
6167 /* Go through the virtual bases, allocating space for each virtual
6168 base that is not already a primary base class. These are
6169 allocated in inheritance graph order. */
6171 {
6176 {
6177 /* This virtual base is not a primary base of any class in the
6178 hierarchy, so we have to add space for it. */
6181 }
6182 }
6183 }
6185 /* Returns the offset of the byte just past the end of the base class
6186 BINFO. */
6188 static tree
6190 {
6191 tree size;
6196 /* An empty class has zero CLASSTYPE_SIZE_UNIT, but we need to
6197 allocate some space for it. It cannot have virtual bases, so
6198 TYPE_SIZE_UNIT is fine. */
6200 else
6204 }
6206 /* Returns the offset of the byte just past the end of the base class
6207 with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then
6208 only non-virtual bases are included. */
6210 static tree
6212 {
6215 tree binfo;
6216 tree base_binfo;
6217 tree offset;
6222 {
6232 }
6237 {
6241 }
6244 }
6246 /* Warn about bases of T that are inaccessible because they are
6247 ambiguous. For example:
6249 struct S {};
6250 struct T : public S {};
6251 struct U : public S, public T {};
6253 Here, `(S*) new U' is not allowed because there are two `S'
6254 subobjects of U. */
6256 static void
6258 {
6261 tree basetype;
6262 tree binfo;
6263 tree base_binfo;
6265 /* If there are no repeated bases, nothing can be ambiguous. */
6269 /* Check direct bases. */
6272 {
6278 }
6280 /* Check for ambiguous virtual bases. */
6284 {
6290 }
6291 }
6293 /* Compare two INTEGER_CSTs K1 and K2. */
6295 static int
6297 {
6299 }
6301 /* Increase the size indicated in RLI to account for empty classes
6302 that are "off the end" of the class. */
6304 static void
6306 {
6307 tree eoc;
6308 tree rli_size;
6310 /* It might be the case that we grew the class to allocate a
6311 zero-sized base class. That won't be reflected in RLI, yet,
6312 because we are willing to overlay multiple bases at the same
6313 offset. However, now we need to make sure that RLI is big enough
6314 to reflect the entire class. */
6320 {
6321 /* The size should have been rounded to a whole byte. */
6324 rli->bitpos
6333 }
6334 }
6336 /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate
6337 BINFO_OFFSETs for all of the base-classes. Position the vtable
6338 pointer. Accumulate declared virtual functions on VIRTUALS_P. */
6340 static void
6342 {
6343 tree non_static_data_members;
6344 tree field;
6345 tree vptr;
6346 record_layout_info rli;
6347 /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of
6348 types that appear at that offset. */
6349 splay_tree empty_base_offsets;
6350 /* True if the last field laid out was a bit-field. */
6352 /* The location at which the next field should be inserted. */
6354 /* T, as a base class. */
6355 tree base_t;
6357 /* Keep track of the first non-static data member. */
6360 /* Start laying out the record. */
6363 /* Mark all the primary bases in the hierarchy. */
6366 /* Create a pointer to our virtual function table. */
6369 /* The vptr is always the first thing in the class. */
6371 {
6376 }
6377 else
6380 /* Build FIELD_DECLs for all of the non-virtual base-types. */
6385 /* Layout the non-static data members. */
6387 {
6388 tree type;
6389 tree padding;
6391 /* We still pass things that aren't non-static data members to
6392 the back end, in case it wants to do something with them. */
6394 {
6396 /* If the static data member has incomplete type, keep track
6397 of it so that it can be completed later. (The handling
6398 of pending statics in finish_record_layout is
6399 insufficient; consider:
6401 struct S1;
6402 struct S2 { static S1 s1; };
6404 At this point, finish_record_layout will be called, but
6405 S1 is still incomplete.) */
6407 {
6409 /* The visibility of static data members is determined
6410 at their point of declaration, not their point of
6411 definition. */
6413 }
6415 }
6423 /* If this field is a bit-field whose width is greater than its
6424 type, then there are some special rules for allocating
6425 it. */
6428 {
6430 /* We must allocate the bits as if suitably aligned for the
6431 longest integer type that fits in this many bits. Then,
6432 we are supposed to use the left over bits as additional
6433 padding. */
6435 /* Do not pick a type bigger than MAX_FIXED_MODE_SIZE. */
6443 {
6445 /* Too big, so our current guess is what we want. */
6447 /* Not bigger than limit, ok */
6449 }
6451 /* Figure out how much additional padding is required. */
6453 /* In a union, the padding field must have the full width
6454 of the bit-field; all fields start at offset zero. */
6456 else
6463 /* An unnamed bitfield does not normally affect the
6464 alignment of the containing class on a target where
6465 PCC_BITFIELD_TYPE_MATTERS. But, the C++ ABI does not
6466 make any exceptions for unnamed bitfields when the
6467 bitfields are longer than their types. Therefore, we
6468 temporarily give the field a name. */
6470 {
6473 }
6479 empty_base_offsets);
6482 /* Now that layout has been performed, set the size of the
6483 field to the size of its declared type; the rest of the
6484 field is effectively invisible. */
6486 /* We must also reset the DECL_MODE of the field. */
6488 }
6489 else
6491 empty_base_offsets);
6493 /* Remember the location of any empty classes in FIELD. */
6496 empty_base_offsets,
6499 /* If a bit-field does not immediately follow another bit-field,
6500 and yet it starts in the middle of a byte, we have failed to
6501 comply with the ABI. */
6504 /* The TREE_NO_WARNING flag gets set by Objective-C when
6505 laying out an Objective-C class. The ObjC ABI differs
6506 from the C++ ABI, and so we do not want a warning
6507 here. */
6509 && !last_field_was_bitfield
6512 bitsize_unit_node)))
6514 "offset of %qD is not ABI-compliant and may "
6517 /* The middle end uses the type of expressions to determine the
6518 possible range of expression values. In order to optimize
6519 "x.i > 7" to "false" for a 2-bit bitfield "i", the middle end
6520 must be made aware of the width of "i", via its type.
6522 Because C++ does not have integer types of arbitrary width,
6523 we must (for the purposes of the front end) convert from the
6524 type assigned here to the declared type of the bitfield
6525 whenever a bitfield expression is used as an rvalue.
6526 Similarly, when assigning a value to a bitfield, the value
6527 must be converted to the type given the bitfield here. */
6529 {
6534 {
6541 }
6542 }
6544 /* If we needed additional padding after this field, add it
6545 now. */
6547 {
6548 tree padding_field;
6551 FIELD_DECL,
6552 NULL_TREE,
6553 char_type_node);
6560 NULL_TREE,
6561 empty_base_offsets);
6562 }
6565 }
6568 {
6569 /* Make sure that we are on a byte boundary so that the size of
6570 the class without virtual bases will always be a round number
6571 of bytes. */
6574 }
6576 /* Delete all zero-width bit-fields from the list of fields. Now
6577 that the type is laid out they are no longer important. */
6580 /* Create the version of T used for virtual bases. We do not use
6581 make_class_type for this version; this is an artificial type. For
6582 a POD type, we just reuse T. */
6584 {
6587 /* Set the size and alignment for the new type. */
6588 tree eoc;
6590 /* If the ABI version is not at least two, and the last
6591 field was a bit-field, RLI may not be on a byte
6592 boundary. In particular, rli_size_unit_so_far might
6593 indicate the last complete byte, while rli_size_so_far
6594 indicates the total number of bits used. Therefore,
6595 rli_size_so_far, rather than rli_size_unit_so_far, is
6596 used to compute TYPE_SIZE_UNIT. */
6604 eoc);
6614 /* Copy the fields from T. */
6618 {
6622 }
6625 /* Record the base version of the type. */
6628 }
6629 else
6632 /* Every empty class contains an empty class. */
6636 /* Set the TYPE_DECL for this type to contain the right
6637 value for DECL_OFFSET, so that we can use it as part
6638 of a COMPONENT_REF for multiple inheritance. */
6641 /* Now fix up any virtual base class types that we left lying
6642 around. We must get these done before we try to lay out the
6643 virtual function table. As a side-effect, this will remove the
6644 base subobject fields. */
6647 /* Make sure that empty classes are reflected in RLI at this
6648 point. */
6651 /* Make sure not to create any structures with zero size. */
6657 /* If this is a non-POD, declaring it packed makes a difference to how it
6658 can be used as a field; don't let finalize_record_size undo it. */
6662 /* Let the back end lay out the type. */
6671 /* Warn about bases that can't be talked about due to ambiguity. */
6674 /* Now that we're done with layout, give the base fields the real types. */
6679 /* Clean up. */
6686 }
6688 /* Determine the "key method" for the class type indicated by TYPE,
6689 and set CLASSTYPE_KEY_METHOD accordingly. */
6691 void
6693 {
6694 tree method;
6701 /* The key method is the first non-pure virtual function that is not
6702 inline at the point of class definition. On some targets the
6703 key function may not be inline; those targets should not call
6704 this function until the end of the translation unit. */
6711 {
6714 }
6717 }
6720 /* Allocate and return an instance of struct sorted_fields_type with
6721 N fields. */
6725 {
6732 }
6734 /* Helper of find_flexarrays. Return true when FLD refers to a non-static
6735 class data member of non-zero size, otherwise false. */
6739 {
6747 {
6751 }
6754 }
6756 /* Used by find_flexarrays and related functions. */
6758 struct flexmems_t
6759 {
6760 /* The first flexible array member or non-zero array member found
6761 in the order of layout. */
6762 tree array;
6763 /* First non-static non-empty data member in the class or its bases. */
6764 tree first;
6765 /* The first non-static non-empty data member following either
6766 the flexible array member, if found, or the zero-length array member
6767 otherwise. AFTER[1] refers to the first such data member of a union
6768 of which the struct containing the flexible array member or zero-length
6769 array is a member, or NULL when no such union exists. This element is
6770 only used during searching, not for diagnosing problems. AFTER[0]
6771 refers to the first such data member that is not a member of such
6772 a union. */
6775 /* Refers to a struct (not union) in which the struct of which the flexible
6776 array is member is defined. Used to diagnose strictly (according to C)
6777 invalid uses of the latter structs. */
6778 tree enclosing;
6779 };
6781 /* Find either the first flexible array member or the first zero-length
6782 array, in that order of preference, among members of class T (but not
6783 its base classes), and set members of FMEM accordingly.
6784 BASE_P is true if T is a base class of another class.
6785 PUN is set to the outermost union in which the flexible array member
6786 (or zero-length array) is defined if one such union exists, otherwise
6787 to NULL.
6788 Similarly, PSTR is set to a data member of the outermost struct of
6789 which the flexible array is a member if one such struct exists,
6790 otherwise to NULL. */
6792 static void
6796 {
6797 /* Set the "pointer" to the outermost enclosing union if not set
6798 yet and maintain it for the remainder of the recursion. */
6803 {
6807 /* Is FLD a typedef for an anonymous struct? */
6809 /* FIXME: Note that typedefs (as well as arrays) need to be fully
6810 handled elsewhere so that errors like the following are detected
6811 as well:
6812 typedef struct { int i, a[], j; } S; // bug c++/72753
6813 S s [2]; // bug c++/68489
6814 */
6819 {
6820 /* Check the nested unnamed type referenced via a typedef
6821 independently of FMEM (since it's not a data member of
6822 the enclosing class). */
6825 }
6827 /* Skip anything that's GCC-generated or not a (non-static) data
6828 member. */
6832 /* Type of the member. */
6837 /* Determine the type of the array element or object referenced
6838 by the member so that it can be checked for flexible array
6839 members if it hasn't been yet. */
6847 {
6849 {
6850 /* Once the member after the flexible array has been found
6851 we're done. */
6854 }
6857 {
6858 /* Descend into the non-static member struct or union and try
6859 to find a flexible array member or zero-length array among
6860 its members. This is only necessary for anonymous types
6861 and types in whose context the current type T has not been
6862 defined (the latter must not be checked again because they
6863 are already in the process of being checked by one of the
6864 recursive calls). */
6869 /* If this member isn't anonymous and a prior non-flexible array
6870 member has been seen in one of the enclosing structs, clear
6871 the FIRST member since it doesn't contribute to the flexible
6872 array struct's members. */
6883 {
6884 /* Restore the FIRST member reset above if no flexible
6885 array member has been found in this member's struct. */
6887 }
6889 /* If the member struct contains the first flexible array
6890 member, or if this member is a base class, continue to
6891 the next member and avoid setting the FMEM->NEXT pointer
6892 to point to it. */
6895 }
6896 }
6899 {
6900 /* Remember the first non-static data member. */
6904 /* Remember the first non-static data member after the flexible
6905 array member, if one has been found, or the zero-length array
6906 if it has been found. */
6909 }
6911 /* Skip non-arrays. */
6915 /* Determine the upper bound of the array if it has one. */
6917 {
6919 {
6920 /* Make a record of the zero-length array if either one
6921 such field or a flexible array member has been seen to
6922 handle the pathological and unlikely case of multiple
6923 such members. */
6926 }
6928 {
6929 /* Remember the first zero-length array unless a flexible array
6930 member has already been seen. */
6933 }
6934 }
6935 else
6936 {
6937 /* Flexible array members have no upper bound. */
6939 {
6940 /* Replace the zero-length array if it's been stored and
6941 reset the after pointer. */
6943 {
6947 }
6948 }
6949 else
6950 {
6953 }
6954 }
6955 }
6956 }
6958 /* Diagnose a strictly (by the C standard) invalid use of a struct with
6959 a flexible array member (or the zero-length array extension). */
6961 static void
6963 {
6975 }
6977 /* Issue diagnostics for invalid flexible array members or zero-length
6978 arrays that are not the last elements of the containing class or its
6979 base classes or that are its sole members. */
6981 static void
6983 {
6988 {
6991 }
6993 /* Has a diagnostic been issued? */
6999 {
7006 {
7010 {
7013 }
7014 }
7015 }
7016 else
7017 {
7024 {
7030 /* In the unlikely event that the member following the flexible
7031 array member is declared in a different class, or the member
7032 overlaps another member of a common union, point to it.
7033 Otherwise it should be obvious. */
7037 {
7042 }
7043 }
7044 }
7048 }
7051 /* Recursively check to make sure that any flexible array or zero-length
7052 array members of class T or its bases are valid (i.e., not the sole
7053 non-static data member of T and, if one exists, that it is the last
7054 non-static data member of T and its base classes. FMEM is expected
7055 to be initially null and is used internally by recursive calls to
7056 the function. Issue the appropriate diagnostics for the array member
7057 that fails the checks. */
7059 static void
7062 {
7063 /* Initialize the result of a search for flexible array and zero-length
7064 array members. Avoid doing any work if the most interesting FMEM data
7065 have already been populated. */
7074 /* Recursively check the primary base class first. */
7076 {
7079 }
7081 /* Recursively check the base classes. */
7084 {
7087 /* The primary base class was already checked above. */
7091 /* Virtual base classes are at the end. */
7095 /* Check the base class. */
7097 }
7100 {
7101 /* Check virtual base classes only once per derived class.
7102 I.e., this check is not performed recursively for base
7103 classes. */
7105 tree base_binfo;
7109 {
7110 /* Check the virtual base class. */
7114 }
7115 }
7117 /* Is the type unnamed (and therefore a member of it potentially
7118 an anonymous struct or union)? */
7121 /* Search the members of the current (possibly derived) class, skipping
7122 unnamed structs and unions since those could be anonymous. */
7127 {
7128 /* Issue diagnostics for invalid flexible and zero-length array
7129 members found in base classes or among the members of the current
7130 class. Ignore anonymous structs and unions whose members are
7131 considered to be members of the enclosing class and thus will
7132 be diagnosed when checking it. */
7134 }
7135 }
7137 /* Perform processing required when the definition of T (a class type)
7138 is complete. Diagnose invalid definitions of flexible array members
7139 and zero-size arrays. */
7141 void
7143 {
7144 tree x;
7145 /* A TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. */
7149 {
7154 }
7156 /* If this type was previously laid out as a forward reference,
7157 make sure we lay it out again. */
7161 /* Make assumptions about the class; we'll reset the flags if
7162 necessary. */
7168 /* Do end-of-class semantic processing: checking the validity of the
7169 bases and members and add implicitly generated methods. */
7172 /* Find the key method. */
7174 {
7175 /* The Itanium C++ ABI permits the key method to be chosen when
7176 the class is defined -- even though the key method so
7177 selected may later turn out to be an inline function. On
7178 some systems (such as ARM Symbian OS) the key method cannot
7179 be determined until the end of the translation unit. On such
7180 systems, we leave CLASSTYPE_KEY_METHOD set to NULL, which
7181 will cause the class to be added to KEYED_CLASSES. Then, in
7182 finish_file we will determine the key method. */
7186 /* If a polymorphic class has no key method, we may emit the vtable
7187 in every translation unit where the class definition appears. If
7188 we're devirtualizing, we can look into the vtable even if we
7189 aren't emitting it. */
7192 }
7194 /* Layout the class itself. */
7197 /* We use the base type for trivial assignments, and hence it
7198 needs a mode. */
7201 /* With the layout complete, check for flexible array members and
7202 zero-length arrays that might overlap other members in the final
7203 layout. */
7208 /* If necessary, create the primary vtable for this class. */
7210 {
7211 /* We must enter these virtuals into the table. */
7215 /* Here we know enough to change the type of our virtual
7216 function table, but we will wait until later this function. */
7219 /* If we're warning about ABI tags, check the types of the new
7220 virtual functions. */
7224 }
7227 {
7229 tree fn;
7236 /* Add entries for virtual functions introduced by this class. */
7240 /* Set DECL_VINDEX for all functions declared in this class. */
7242 fn;
7244 vindex += (TARGET_VTABLE_USES_DESCRIPTORS
7246 {
7250 /* A thunk. We should never be calling this entry directly
7251 from this vtable -- we'd use the entry for the non
7252 thunk base function. */
7256 }
7257 }
7264 /* Complete the rtl for any static member objects of the type we're
7265 working on. */
7272 /* Done with FIELDS...now decide whether to sort these for
7273 faster lookups later.
7275 We use a small number because most searches fail (succeeding
7276 ultimately as the search bores through the inheritance
7277 hierarchy), and we want this failure to occur quickly. */
7281 /* Complain if one of the field types requires lower visibility. */
7284 /* Make the rtl for any new vtables we have created, and unmark
7285 the base types we marked. */
7288 /* Build the VTT for T. */
7295 "%q#T has virtual functions and accessible"
7303 /* Class layout, assignment of virtual table slots, etc., is now
7304 complete. Give the back end a chance to tweak the visibility of
7305 the class or perform any other required target modifications. */
7315 /* Finish debugging output for this type. */
7319 {
7322 {
7325 }
7327 {
7330 else
7331 {
7334 }
7336 }
7338 {
7340 "the type of the first field has a different ABI from the "
7343 }
7344 }
7345 }
7347 /* Insert FIELDS into T for the sorted case if the FIELDS count is
7348 equal to THRESHOLD or greater than THRESHOLD. */
7350 static void
7352 {
7355 {
7360 }
7361 }
7363 /* Insert lately defined enum ENUMTYPE into T for the sorted case. */
7365 void
7367 {
7370 {
7372 int n_fields
7383 }
7384 }
7386 /* When T was built up, the member declarations were added in reverse
7387 order. Rearrange them to declaration order. */
7389 void
7391 {
7392 tree next;
7393 tree prev;
7394 tree x;
7396 /* The following lists are all in reverse order. Put them in
7397 declaration order now. */
7401 /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in
7402 reverse order, so we can't just use nreverse. */
7407 {
7411 }
7413 {
7417 }
7418 }
7420 tree
7422 {
7425 /* Now that we've got all the field declarations, reverse everything
7426 as necessary. */
7432 /* Nadger the current location so that diagnostics point to the start of
7433 the struct, not the end. */
7437 {
7438 tree x;
7444 /* We need to emit an error message if this type was used as a parameter
7445 and it is an abstract type, even if it is a template. We construct
7446 a simple CLASSTYPE_PURE_VIRTUALS list without taking bases into
7447 account and we call complete_vars with this type, which will check
7448 the PARM_DECLS. Note that while the type is being defined,
7449 CLASSTYPE_PURE_VIRTUALS contains the list of the inline friends
7450 (see CLASSTYPE_INLINE_FRIENDS) so we need to clear it. */
7456 /* We need to add the target functions to the CLASSTYPE_METHOD_VEC if
7457 an enclosing scope is a template class, so that this function be
7458 found by lookup_fnfields_1 when the using declaration is not
7459 instantiated yet. */
7462 {
7467 }
7469 /* Remember current #pragma pack value. */
7472 /* Fix up any variants we've already built. */
7474 {
7479 }
7480 }
7481 else
7485 {
7486 /* People keep complaining that the compiler crashes on an invalid
7487 definition of initializer_list, so I guess we should explicitly
7488 reject it. What the compiler internals care about is that it's a
7489 template and has a pointer field followed by an integer field. */
7492 {
7495 {
7499 }
7500 }
7503 "definition of std::initializer_list does not match "
7505 }
7513 else
7517 /* Lambdas are defined by the LAMBDA_EXPR. */
7522 }
7523 \f
7524 /* Hash table to avoid endless recursion when handling references. */
7527 /* Return the dynamic type of INSTANCE, if known.
7528 Used to determine whether the virtual function table is needed
7529 or not.
7531 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
7532 of our knowledge of its type. *NONNULL should be initialized
7533 before this function is called. */
7535 static tree
7537 {
7538 #define RECUR(T) fixed_type_or_null((T), nonnull, cdtorp)
7541 {
7545 else
7549 /* This is a call to a constructor, hence it's never zero. */
7551 {
7555 }
7559 /* This is a call to a constructor, hence it's never zero. */
7561 {
7565 }
7574 /* Propagate nonnull. */
7579 CASE_CONVERT:
7585 {
7586 /* Just because we see an ADDR_EXPR doesn't mean we're dealing
7587 with a real object -- given &p->f, p can still be null. */
7589 /* ??? Probably should check DECL_WEAK here. */
7592 }
7596 /* If this component is really a base class reference, then the field
7597 itself isn't definitive. */
7606 {
7610 }
7611 /* fall through. */
7616 {
7620 }
7622 {
7626 /* if we're in a ctor or dtor, we know our type. If
7627 current_class_ptr is set but we aren't in a function, we're in
7628 an NSDMI (and therefore a constructor). */
7633 {
7637 }
7638 }
7640 {
7641 /* We only need one hash table because it is always left empty. */
7643 fixed_type_or_null_ref_ht
7646 /* Reference variables should be references to objects. */
7650 /* Enter the INSTANCE in a table to prevent recursion; a
7651 variable's initializer may refer to the variable
7652 itself. */
7657 {
7658 tree type;
7667 }
7668 }
7673 }
7674 #undef RECUR
7675 }
7677 /* Return nonzero if the dynamic type of INSTANCE is known, and
7678 equivalent to the static type. We also handle the case where
7679 INSTANCE is really a pointer. Return negative if this is a
7680 ctor/dtor. There the dynamic type is known, but this might not be
7681 the most derived base of the original object, and hence virtual
7682 bases may not be laid out according to this type.
7684 Used to determine whether the virtual function table is needed
7685 or not.
7687 *NONNULL is set iff INSTANCE can be known to be nonnull, regardless
7688 of our knowledge of its type. *NONNULL should be initialized
7689 before this function is called. */
7691 int
7693 {
7696 tree fixed;
7698 /* processing_template_decl can be false in a template if we're in
7699 instantiate_non_dependent_expr, but we still want to suppress
7700 this check. */
7702 {
7703 /* In a template we only care about the type of the result. */
7707 }
7717 }
7719 \f
7720 void
7722 {
7725 current_class_stack
7733 }
7735 /* Restore the cached PREVIOUS_CLASS_LEVEL. */
7737 static void
7739 {
7740 tree type;
7742 /* We are re-entering the same class we just left, so we don't
7743 have to search the whole inheritance matrix to find all the
7744 decls to bind again. Instead, we install the cached
7745 class_shadowed list and walk through it binding names. */
7748 /* Restore IDENTIFIER_TYPE_VALUE. */
7750 type;
7753 }
7755 /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE as
7756 appropriate for TYPE.
7758 So that we may avoid calls to lookup_name, we cache the _TYPE
7759 nodes of local TYPE_DECLs in the TREE_TYPE field of the name.
7761 For multiple inheritance, we perform a two-pass depth-first search
7762 of the type lattice. */
7764 void
7766 {
7767 class_stack_node_t csn;
7771 /* Make sure there is enough room for the new entry on the stack. */
7773 {
7775 current_class_stack
7777 current_class_stack_size);
7778 }
7780 /* Insert a new entry on the class stack. */
7787 current_class_depth++;
7789 /* Now set up the new type. */
7795 /* By default, things in classes are private, while things in
7796 structures or unions are public. */
7798 ? access_private_node
7804 {
7805 /* Forcibly remove any old class remnants. */
7807 }
7813 else
7815 }
7817 /* When we exit a toplevel class scope, we save its binding level so
7818 that we can restore it quickly. Here, we've entered some other
7819 class, so we must invalidate our cache. */
7821 void
7823 {
7825 }
7827 /* Get out of the current class scope. If we were in a class scope
7828 previously, that is the one popped to. */
7830 void
7832 {
7835 current_class_depth--;
7841 }
7843 /* Mark the top of the class stack as hidden. */
7845 void
7847 {
7850 }
7852 /* Mark the top of the class stack as un-hidden. */
7854 void
7856 {
7859 }
7861 /* Returns 1 if the class type currently being defined is either T or
7862 a nested type of T. Returns the type from the current_class_stack,
7863 which might be equivalent to but not equal to T in case of
7864 constrained partial specializations. */
7866 tree
7868 {
7876 /* We start looking from 1 because entry 0 is from global scope,
7877 and has no type. */
7879 {
7880 tree c;
7883 else
7884 {
7888 }
7893 }
7895 }
7897 /* If either current_class_type or one of its enclosing classes are derived
7898 from T, return the appropriate type. Used to determine how we found
7899 something via unqualified lookup. */
7901 tree
7903 {
7906 /* The bases of a dependent type are unknown. */
7917 {
7922 }
7925 }
7927 /* Return the outermost enclosing class type that is still open, or
7928 NULL_TREE. */
7930 tree
7932 {
7939 {
7946 }
7948 }
7950 /* Returns the innermost class type which is not a lambda closure type. */
7952 tree
7954 {
7957 /* We start looking from 1 because entry 0 is from global scope,
7958 and has no type. */
7960 {
7961 tree c;
7964 else
7965 {
7969 }
7974 }
7976 }
7978 /* When entering a class scope, all enclosing class scopes' names with
7979 static meaning (static variables, static functions, types and
7980 enumerators) have to be visible. This recursive function calls
7981 pushclass for all enclosing class contexts until global or a local
7982 scope is reached. TYPE is the enclosed class. */
7984 void
7986 {
7987 /* A namespace might be passed in error cases, like A::B:C. */
7995 }
7997 /* Undoes a push_nested_class call. */
7999 void
8001 {
8007 }
8009 /* Returns the number of extern "LANG" blocks we are nested within. */
8011 int
8013 {
8015 }
8017 /* Set global variables CURRENT_LANG_NAME to appropriate value
8018 so that behavior of name-mangling machinery is correct. */
8020 void
8022 {
8029 else
8031 }
8033 /* Get out of the current language scope. */
8035 void
8037 {
8039 }
8040 \f
8041 /* Type instantiation routines. */
8043 /* Given an OVERLOAD and a TARGET_TYPE, return the function that
8044 matches the TARGET_TYPE. If there is no satisfactory match, return
8045 error_mark_node, and issue an error & warning messages under
8046 control of FLAGS. Permit pointers to member function if FLAGS
8047 permits. If TEMPLATE_ONLY, the name of the overloaded function was
8048 a template-id, and EXPLICIT_TARGS are the explicitly provided
8049 template arguments.
8051 If OVERLOAD is for one or more member functions, then ACCESS_PATH
8052 is the base path used to reference those member functions. If
8053 the address is resolved to a member function, access checks will be
8054 performed and errors issued if appropriate. */
8056 static tree
8058 tree overload,
8059 tsubst_flags_t complain,
8061 tree explicit_targs,
8062 tree access_path)
8063 {
8064 /* Here's what the standard says:
8066 [over.over]
8068 If the name is a function template, template argument deduction
8069 is done, and if the argument deduction succeeds, the deduced
8070 arguments are used to generate a single template function, which
8071 is added to the set of overloaded functions considered.
8073 Non-member functions and static member functions match targets of
8074 type "pointer-to-function" or "reference-to-function." Nonstatic
8075 member functions match targets of type "pointer-to-member
8076 function;" the function type of the pointer to member is used to
8077 select the member function from the set of overloaded member
8078 functions. If a nonstatic member function is selected, the
8079 reference to the overloaded function name is required to have the
8080 form of a pointer to member as described in 5.3.1.
8082 If more than one function is selected, any template functions in
8083 the set are eliminated if the set also contains a non-template
8084 function, and any given template function is eliminated if the
8085 set contains a second template function that is more specialized
8086 than the first according to the partial ordering rules 14.5.5.2.
8087 After such eliminations, if any, there shall remain exactly one
8088 selected function. */
8091 /* We store the matches in a TREE_LIST rooted here. The functions
8092 are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy
8093 interoperability with most_specialized_instantiation. */
8095 tree fn;
8096 tree target_fn_type;
8098 /* By the time we get here, we should be seeing only real
8099 pointer-to-member types, not the internal POINTER_TYPE to
8100 METHOD_TYPE representation. */
8106 /* Check that the TARGET_TYPE is reasonable. */
8111 /* This is OK, too. */
8114 /* This is OK, too. This comes from a conversion to reference
8115 type. */
8117 else
8118 {
8124 }
8126 /* Non-member functions and static member functions match targets of type
8127 "pointer-to-function" or "reference-to-function." Nonstatic member
8128 functions match targets of type "pointer-to-member-function;" the
8129 function type of the pointer to member is used to select the member
8130 function from the set of overloaded member functions.
8132 So figure out the FUNCTION_TYPE that we want to match against. */
8135 /* If we can find a non-template function that matches, we can just
8136 use it. There's no point in generating template instantiations
8137 if we're just going to throw them out anyhow. But, of course, we
8138 can only do this when we don't *need* a template function. */
8141 {
8145 /* We're not looking for templates just yet. */
8149 /* We're looking for a non-static member, and this isn't
8150 one, or vice versa. */
8153 /* In C++17 we need the noexcept-qualifier to compare types. */
8157 /* See if there's a match. */
8162 }
8164 /* Now, if we've already got a match (or matches), there's no need
8165 to proceed to the template functions. But, if we don't have a
8166 match we need to look at them, too. */
8168 {
8169 tree target_arg_types;
8170 tree target_ret_type;
8173 tree arg;
8187 {
8189 tree instantiation;
8190 tree targs;
8193 /* We're only looking for templates. */
8198 /* We're not looking for a non-static member, and this is
8199 one, or vice versa. */
8204 /* If the template has a deduced return type, don't expose it to
8205 template argument deduction. */
8209 /* Try to do argument deduction. */
8216 /* Instantiation failed. */
8219 /* Constraints must be satisfied. This is done before
8220 return type deduction since that instantiates the
8221 function. */
8225 /* And now force instantiation to do return type deduction. */
8227 {
8233 }
8235 /* In C++17 we need the noexcept-qualifier to compare types. */
8239 /* See if there's a match. */
8244 }
8246 /* Now, remove all but the most specialized of the matches. */
8248 {
8253 NULL_TREE,
8254 NULL_TREE);
8255 }
8256 }
8258 /* Now we should have exactly one function in MATCHES. */
8260 {
8261 /* There were *no* matches. */
8263 {
8268 }
8270 }
8272 {
8273 /* There were too many matches. First check if they're all
8274 the same function. */
8279 /* For multi-versioned functions, more than one match is just fine and
8280 decls_match will return false as they are different. */
8288 {
8290 {
8294 /* Since print_candidates expects the functions in the
8295 TREE_VALUE slot, we flip them here. */
8300 }
8303 }
8304 }
8306 /* Good, exactly one match. Now, convert it to the correct type. */
8311 {
8319 {
8322 }
8323 }
8325 /* If a pointer to a function that is multi-versioned is requested, the
8326 pointer to the dispatcher function is returned instead. This works
8327 well because indirectly calling the function will dispatch the right
8328 function version at run-time. */
8330 {
8334 /* Mark all the versions corresponding to the dispatcher as used. */
8337 }
8339 /* If we're doing overload resolution purely for the purpose of
8340 determining conversion sequences, we should not consider the
8341 function used. If this conversion sequence is selected, the
8342 function will be marked as used at this point. */
8344 {
8345 /* Make =delete work with SFINAE. */
8350 }
8352 /* We could not check access to member functions when this
8353 expression was originally created since we did not know at that
8354 time to which function the expression referred. */
8356 {
8359 }
8363 else
8364 {
8365 /* The target must be a REFERENCE_TYPE. Above, cp_build_unary_op
8366 will mark the function as addressed, but here we must do it
8367 explicitly. */
8371 }
8372 }
8374 /* This function will instantiate the type of the expression given in
8375 RHS to match the type of LHSTYPE. If errors exist, then return
8376 error_mark_node. COMPLAIN is a bit mask. If TF_ERROR is set, then
8377 we complain on errors. If we are not complaining, never modify rhs,
8378 as overload resolution wants to try many possible instantiations, in
8379 the hope that at least one will work.
8381 For non-recursive calls, LHSTYPE should be a function, pointer to
8382 function, or a pointer to member function. */
8384 tree
8386 {
8393 {
8397 }
8400 {
8409 /* Microsoft allows `A::f' to be resolved to a
8410 pointer-to-member. */
8411 ;
8412 else
8413 {
8418 }
8419 }
8422 {
8425 }
8427 /* If we are in a template, and have a NON_DEPENDENT_EXPR, we cannot
8428 deduce any type information. */
8430 {
8434 }
8436 /* If we instantiate a template, and it is a A ?: C expression
8437 with omitted B, look through the SAVE_EXPR. */
8441 /* There are only a few kinds of expressions that may have a type
8442 dependent on overload resolution. */
8448 /* This should really only be used when attempting to distinguish
8449 what sort of a pointer to function we have. For now, any
8450 arithmetic operation which is not supported on pointers
8451 is rejected as an error. */
8454 {
8456 {
8462 /* Do not lose object's side effects. */
8466 }
8473 /* This can happen if we are forming a pointer-to-member for a
8474 member template. */
8477 /* Fall through. */
8480 {
8484 return
8488 }
8492 return
8496 access_path);
8499 {
8504 }
8511 }
8513 }
8514 \f
8515 /* Return the name of the virtual function pointer field
8516 (as an IDENTIFIER_NODE) for the given TYPE. Note that
8517 this may have to look back through base types to find the
8518 ultimate field name. (For single inheritance, these could
8519 all be the same name. Who knows for multiple inheritance). */
8521 static tree
8523 {
8530 {
8536 }
8544 }
8546 void
8548 {
8555 {
8560 }
8561 }
8563 /* Build a dummy reference to ourselves so Derived::Base (and A::A) works,
8564 according to [class]:
8565 The class-name is also inserted
8566 into the scope of the class itself. For purposes of access checking,
8567 the inserted class name is treated as if it were a public member name. */
8569 void
8571 {
8574 tree saved_cas;
8589 }
8591 /* Returns 1 if TYPE contains only padding bytes. */
8593 int
8595 {
8603 }
8605 /* Returns true if TYPE contains no actual data, just various
8606 possible combinations of empty classes and possibly a vptr. */
8608 bool
8610 {
8612 {
8613 tree field;
8614 tree binfo;
8615 tree base_binfo;
8618 /* CLASSTYPE_EMPTY_P isn't set properly until the class is actually laid
8619 out, but we'd like to be able to check this before then. */
8630 /* An unnamed bit-field is not a data member. */
8635 }
8640 }
8642 /* Note that NAME was looked up while the current class was being
8643 defined and that the result of that lookup was DECL. */
8645 void
8647 {
8648 splay_tree names_used;
8650 /* If we're not defining a class, there's nothing to do. */
8656 /* If there's already a binding for this NAME, then we don't have
8657 anything to worry about. */
8670 }
8672 /* Note that NAME was declared (as DECL) in the current class. Check
8673 to see that the declaration is valid. */
8675 void
8677 {
8678 splay_tree names_used;
8679 splay_tree_node n;
8681 /* Look to see if we ever used this name. */
8682 names_used
8686 /* The C language allows members to be declared with a type of the same
8687 name, and the C++ standard says this diagnostic is not required. So
8688 allow it in extern "C" blocks unless predantic is specified.
8689 Allow it in all cases if -ms-extensions is specified. */
8695 {
8696 /* [basic.scope.class]
8698 A name N used in a class S shall refer to the same declaration
8699 in its context and when re-evaluated in the completed scope of
8700 S. */
8705 }
8706 }
8708 /* Returns the VAR_DECL for the complete vtable associated with BINFO.
8709 Secondary vtables are merged with primary vtables; this function
8710 will return the VAR_DECL for the primary vtable. */
8712 tree
8714 {
8715 tree decl;
8719 {
8722 }
8726 }
8729 /* Returns the binfo for the primary base of BINFO. If the resulting
8730 BINFO is a virtual base, and it is inherited elsewhere in the
8731 hierarchy, then the returned binfo might not be the primary base of
8732 BINFO in the complete object. Check BINFO_PRIMARY_P or
8733 BINFO_LOST_PRIMARY_P to be sure. */
8735 static tree
8737 {
8738 tree primary_base;
8745 }
8747 /* As above, but iterate until we reach the binfo that actually provides the
8748 vptr for BINFO. */
8750 static tree
8752 {
8756 {
8761 }
8763 }
8765 /* Returns true if BINFO gets its vptr from a virtual base of the most derived
8766 type. Note that the virtual inheritance might be above or below BINFO in
8767 the hierarchy. */
8769 bool
8771 {
8775 /* Don't limit binfo_via_virtual, we want to return true when BINFO itself is
8776 a morally virtual base. */
8779 }
8781 /* If INDENTED_P is zero, indent to INDENT. Return nonzero. */
8783 static int
8785 {
8789 }
8791 /* Dump the offsets of all the bases rooted at BINFO to STREAM.
8792 INDENT should be zero when called from the top level; it is
8793 incremented recursively. IGO indicates the next expected BINFO in
8794 inheritance graph ordering. */
8796 static tree
8798 dump_flags_t flags,
8799 tree binfo,
8800 tree igo,
8802 {
8804 tree base_binfo;
8812 {
8815 }
8830 {
8834 TFF_PLAIN_IDENTIFIER),
8836 }
8838 {
8841 }
8846 {
8850 {
8854 TFF_PLAIN_IDENTIFIER));
8855 }
8857 {
8861 TFF_PLAIN_IDENTIFIER));
8862 }
8864 {
8868 TFF_PLAIN_IDENTIFIER));
8869 }
8871 {
8875 TFF_PLAIN_IDENTIFIER));
8876 }
8880 }
8886 }
8888 /* Dump the BINFO hierarchy for T. */
8890 static void
8892 {
8904 }
8906 /* Debug interface to hierarchy dumping. */
8908 void
8910 {
8912 }
8914 static void
8916 {
8917 dump_flags_t flags;
8919 {
8922 }
8923 }
8925 static void
8927 {
8928 tree value;
8930 HOST_WIDE_INT elt;
8938 TFF_PLAIN_IDENTIFIER));
8945 }
8947 static void
8949 {
8950 dump_flags_t flags;
8957 {
8964 {
8969 }
8973 }
8976 }
8978 static void
8980 {
8981 dump_flags_t flags;
8988 {
8993 }
8996 }
8998 /* Dump a function or thunk and its thunkees. */
9000 static void
9002 {
9005 tree thunks;
9013 {
9023 else
9029 }
9033 }
9035 /* Dump the thunks for FN. */
9037 void
9039 {
9041 }
9043 /* Virtual function table initialization. */
9045 /* Create all the necessary vtables for T and its base classes. */
9047 static void
9049 {
9050 tree vbase;
9054 /* We lay out the primary and secondary vtables in one contiguous
9055 vtable. The primary vtable is first, followed by the non-virtual
9056 secondary vtables in inheritance graph order. */
9060 /* Then come the virtual bases, also in inheritance graph order. */
9062 {
9066 }
9070 }
9072 /* Initialize the vtable for BINFO with the INITS. */
9074 static void
9076 {
9077 tree decl;
9083 }
9085 /* Build the VTT (virtual table table) for T.
9086 A class requires a VTT if it has virtual bases.
9088 This holds
9089 1 - primary virtual pointer for complete object T
9090 2 - secondary VTTs for each direct non-virtual base of T which requires a
9091 VTT
9092 3 - secondary virtual pointers for each direct or indirect base of T which
9093 has virtual bases or is reachable via a virtual path from T.
9094 4 - secondary VTTs for each direct or indirect virtual base of T.
9096 Secondary VTTs look like complete object VTTs without part 4. */
9098 static void
9100 {
9101 tree type;
9102 tree vtt;
9103 tree index;
9106 /* Build up the initializers for the VTT. */
9111 /* If we didn't need a VTT, we're done. */
9115 /* Figure out the type of the VTT. */
9119 /* Now, build the VTT object itself. */
9122 /* Add the VTT to the vtables list. */
9127 }
9129 /* When building a secondary VTT, BINFO_VTABLE is set to a TREE_LIST with
9130 PURPOSE the RTTI_BINFO, VALUE the real vtable pointer for this binfo,
9131 and CHAIN the vtable pointer for this binfo after construction is
9132 complete. VALUE can also be another BINFO, in which case we recurse. */
9134 static tree
9136 {
9137 tree vt;
9140 {
9146 else
9148 }
9151 }
9153 /* Data for secondary VTT initialization. */
9154 struct secondary_vptr_vtt_init_data
9155 {
9156 /* Is this the primary VTT? */
9159 /* Current index into the VTT. */
9160 tree index;
9162 /* Vector of initializers built up. */
9165 /* The type being constructed by this secondary VTT. */
9166 tree type_being_constructed;
9167 };
9169 /* Recursively build the VTT-initializer for BINFO (which is in the
9170 hierarchy dominated by T). INITS points to the end of the initializer
9171 list to date. INDEX is the VTT index where the next element will be
9172 replaced. Iff BINFO is the binfo for T, this is the top level VTT (i.e.
9173 not a subvtt for some base of T). When that is so, we emit the sub-VTTs
9174 for virtual bases of T. When it is not so, we build the constructor
9175 vtables for the BINFO-in-T variant. */
9177 static void
9180 {
9182 tree b;
9183 tree init;
9184 secondary_vptr_vtt_init_data data;
9187 /* We only need VTTs for subobjects with virtual bases. */
9191 /* We need to use a construction vtable if this is not the primary
9192 VTT. */
9194 {
9197 /* Record the offset in the VTT where this sub-VTT can be found. */
9199 }
9201 /* Add the address of the primary vtable for the complete object. */
9205 {
9208 }
9211 /* Recursively add the secondary VTTs for non-virtual bases. */
9216 /* Add secondary virtual pointers for all subobjects of BINFO with
9217 either virtual bases or reachable along a virtual path, except
9218 subobjects that are non-virtual primary bases. */
9228 /* data.inits might have grown as we added secondary virtual pointers.
9229 Make sure our caller knows about the new vector. */
9233 /* Add the secondary VTTs for virtual bases in inheritance graph
9234 order. */
9236 {
9241 }
9242 else
9243 /* Remove the ctor vtables we created. */
9245 }
9247 /* Called from build_vtt_inits via dfs_walk. BINFO is the binfo for the base
9248 in most derived. DATA is a SECONDARY_VPTR_VTT_INIT_DATA structure. */
9250 static tree
9252 {
9255 /* We don't care about bases that don't have vtables. */
9259 /* We're only interested in proper subobjects of the type being
9260 constructed. */
9264 /* We're only interested in bases with virtual bases or reachable
9265 via a virtual path from the type being constructed. */
9270 /* We're not interested in non-virtual primary bases. */
9274 /* Record the index where this secondary vptr can be found. */
9276 {
9281 {
9282 /* It's a primary virtual base, and this is not a
9283 construction vtable. Find the base this is primary of in
9284 the inheritance graph, and use that base's vtable
9285 now. */
9288 }
9289 }
9291 /* Add the initializer for the secondary vptr itself. */
9294 /* Advance the vtt index. */
9299 }
9301 /* Called from build_vtt_inits via dfs_walk. After building
9302 constructor vtables and generating the sub-vtt from them, we need
9303 to restore the BINFO_VTABLES that were scribbled on. DATA is the
9304 binfo of the base whose sub vtt was generated. */
9306 static tree
9308 {
9312 /* If this class has no vtable, none of its bases do. */
9316 /* This might be a primary base, so have no vtable in this
9317 hierarchy. */
9320 /* If we scribbled the construction vtable vptr into BINFO, clear it
9321 out now. */
9327 }
9329 /* Build the construction vtable group for BINFO which is in the
9330 hierarchy dominated by T. */
9332 static void
9334 {
9335 tree type;
9336 tree vtbl;
9337 tree id;
9338 tree vbase;
9341 /* See if we've already created this construction vtable group. */
9347 /* Build a version of VTBL (with the wrong type) for use in
9348 constructing the addresses of secondary vtables in the
9349 construction vtable group. */
9352 /* Don't export construction vtables from shared libraries. Even on
9353 targets that don't support hidden visibility, this tells
9354 can_refer_decl_in_current_unit_p not to assume that it's safe to
9355 access from a different compilation unit (bz 54314). */
9363 /* Add the vtables for each of our virtual bases using the vbase in T
9364 binfo. */
9366 vbase;
9368 {
9369 tree b;
9376 }
9378 /* Figure out the type of the construction vtable. */
9385 /* Initialize the construction vtable. */
9389 }
9391 /* Add the vtbl initializers for BINFO (and its bases other than
9392 non-virtual primaries) to the list of INITS. BINFO is in the
9393 hierarchy dominated by T. RTTI_BINFO is the binfo within T of
9394 the constructor the vtbl inits should be accumulated for. (If this
9395 is the complete object vtbl then RTTI_BINFO will be TYPE_BINFO (T).)
9396 ORIG_BINFO is the binfo for this object within BINFO_TYPE (RTTI_BINFO).
9397 BINFO is the active base equivalent of ORIG_BINFO in the inheritance
9398 graph of T. Both BINFO and ORIG_BINFO will have the same BINFO_TYPE,
9399 but are not necessarily the same in terms of layout. */
9401 static void
9403 tree orig_binfo,
9404 tree rtti_binfo,
9405 tree vtbl,
9406 tree t,
9408 {
9410 tree base_binfo;
9415 /* If it doesn't have a vptr, we don't do anything. */
9419 /* If we're building a construction vtable, we're not interested in
9420 subobjects that don't require construction vtables. */
9426 /* Build the initializers for the BINFO-in-T vtable. */
9429 /* Walk the BINFO and its bases. We walk in preorder so that as we
9430 initialize each vtable we can figure out at what offset the
9431 secondary vtable lies from the primary vtable. We can't use
9432 dfs_walk here because we need to iterate through bases of BINFO
9433 and RTTI_BINFO simultaneously. */
9435 {
9436 /* Skip virtual bases. */
9442 inits);
9443 }
9444 }
9446 /* Called from accumulate_vtbl_inits. Adds the initializers for the
9447 BINFO vtable to L. */
9449 static void
9451 tree orig_binfo,
9452 tree rtti_binfo,
9453 tree orig_vtbl,
9454 tree t,
9456 {
9463 {
9464 /* In the hierarchy of BINFO_TYPE (RTTI_BINFO), this is a
9465 primary virtual base. If it is not the same primary in
9466 the hierarchy of T, we'll need to generate a ctor vtable
9467 for it, to place at its location in T. If it is the same
9468 primary, we still need a VTT entry for the vtable, but it
9469 should point to the ctor vtable for the base it is a
9470 primary for within the sub-hierarchy of RTTI_BINFO.
9472 There are three possible cases:
9474 1) We are in the same place.
9475 2) We are a primary base within a lost primary virtual base of
9476 RTTI_BINFO.
9477 3) We are primary to something not a base of RTTI_BINFO. */
9479 tree b;
9482 /* First, look through the bases we are primary to for RTTI_BINFO
9483 or a virtual base. */
9486 {
9491 }
9492 /* If we run out of primary links, keep looking down our
9493 inheritance chain; we might be an indirect primary. */
9497 found:
9499 /* If we found RTTI_BINFO, this is case 1. If we found a virtual
9500 base B and it is a base of RTTI_BINFO, this is case 2. In
9501 either case, we share our vtable with LAST, i.e. the
9502 derived-most base within B of which we are a primary. */
9505 /* Just set our BINFO_VTABLE to point to LAST, as we may not have
9506 set LAST's BINFO_VTABLE yet. We'll extract the actual vptr in
9507 binfo_ctor_vtable after everything's been set up. */
9510 /* Otherwise, this is case 3 and we get our own. */
9511 }
9518 {
9519 tree index;
9522 /* Add the initializer for this vtable. */
9526 /* Figure out the position to which the VPTR should point. */
9532 }
9535 /* For a construction vtable, we can't overwrite BINFO_VTABLE.
9536 So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will
9537 straighten this out. */
9540 /* Throw away any unneeded intializers. */
9542 else
9543 /* For an ordinary vtable, set BINFO_VTABLE. */
9545 }
9550 /* Construct the initializer for BINFO's virtual function table. BINFO
9551 is part of the hierarchy dominated by T. If we're building a
9552 construction vtable, the ORIG_BINFO is the binfo we should use to
9553 find the actual function pointers to put in the vtable - but they
9554 can be overridden on the path to most-derived in the graph that
9555 ORIG_BINFO belongs. Otherwise,
9556 ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the
9557 BINFO that should be indicated by the RTTI information in the
9558 vtable; it will be a base class of T, rather than T itself, if we
9559 are building a construction vtable.
9561 The value returned is a TREE_LIST suitable for wrapping in a
9562 CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If
9563 NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the
9564 number of non-function entries in the vtable.
9566 It might seem that this function should never be called with a
9567 BINFO for which BINFO_PRIMARY_P holds, the vtable for such a
9568 base is always subsumed by a derived class vtable. However, when
9569 we are building construction vtables, we do build vtables for
9570 primary bases; we need these while the primary base is being
9571 constructed. */
9573 static void
9575 tree orig_binfo,
9576 tree t,
9577 tree rtti_binfo,
9580 {
9581 tree v;
9582 vtbl_init_data vid;
9584 tree vbinfo;
9588 /* Initialize VID. */
9596 /* The first vbase or vcall offset is at index -3 in the vtable. */
9599 /* Add entries to the vtable for RTTI. */
9602 /* Create an array for keeping track of the functions we've
9603 processed. When we see multiple functions with the same
9604 signature, we share the vcall offsets. */
9606 /* Add the vcall and vbase offset entries. */
9609 /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
9610 build_vbase_offset_vtbl_entries. */
9615 /* If the target requires padding between data entries, add that now. */
9617 {
9622 /* Move data entries into their new positions and add padding
9623 after the new positions. Iterate backwards so we don't
9624 overwrite entries that we would need to process later. */
9627 ix--)
9628 {
9636 {
9640 null_pointer_node);
9641 }
9642 }
9643 }
9648 /* The initializers for virtual functions were built up in reverse
9649 order. Straighten them out and add them to the running list in one
9650 step. */
9659 /* Go through all the ordinary virtual functions, building up
9660 initializers. */
9662 {
9663 tree delta;
9664 tree vcall_index;
9671 {
9675 {
9678 }
9680 }
9682 /* If the only definition of this function signature along our
9683 primary base chain is from a lost primary, this vtable slot will
9684 never be used, so just zero it out. This is important to avoid
9685 requiring extra thunks which cannot be generated with the function.
9687 We first check this in update_vtable_entry_for_fn, so we handle
9688 restored primary bases properly; we also need to do it here so we
9689 zero out unused slots in ctor vtables, rather than filling them
9690 with erroneous values (though harmless, apart from relocation
9691 costs). */
9696 {
9697 /* Pull the offset for `this', and the function to call, out of
9698 the list. */
9705 /* You can't call an abstract virtual function; it's abstract.
9706 So, we replace these functions with __pure_virtual. */
9708 {
9711 {
9713 abort_fndecl_addr
9717 }
9718 }
9719 /* Likewise for deleted virtuals. */
9721 {
9723 {
9727 dvirt_fn = push_library_fn
9731 }
9736 }
9737 else
9738 {
9740 {
9745 }
9746 /* Take the address of the function, considering it to be of an
9747 appropriate generic type. */
9751 /* Don't refer to a virtual destructor from a constructor
9752 vtable or a vtable for an abstract class, since destroying
9753 an object under construction is undefined behavior and we
9754 don't want it to be considered a candidate for speculative
9755 devirtualization. But do create the thunk for ABI
9756 compliance. */
9761 }
9762 }
9764 /* And add it to the chain of initializers. */
9766 {
9771 else
9773 {
9779 }
9780 }
9781 else
9783 }
9784 }
9786 /* Adds to vid->inits the initializers for the vbase and vcall
9787 offsets in BINFO, which is in the hierarchy dominated by T. */
9789 static void
9791 {
9792 tree b;
9794 /* If this is a derived class, we must first create entries
9795 corresponding to the primary base class. */
9800 /* Add the vbase entries for this base. */
9802 /* Add the vcall entries for this base. */
9804 }
9806 /* Returns the initializers for the vbase offset entries in the vtable
9807 for BINFO (which is part of the class hierarchy dominated by T), in
9808 reverse order. VBASE_OFFSET_INDEX gives the vtable index
9809 where the next vbase offset will go. */
9811 static void
9813 {
9814 tree vbase;
9815 tree t;
9816 tree non_primary_binfo;
9818 /* If there are no virtual baseclasses, then there is nothing to
9819 do. */
9825 /* We might be a primary base class. Go up the inheritance hierarchy
9826 until we find the most derived class of which we are a primary base:
9827 it is the offset of that which we need to use. */
9830 {
9831 tree b;
9833 /* If we have reached a virtual base, then it must be a primary
9834 base (possibly multi-level) of vid->binfo, or we wouldn't
9835 have called build_vcall_and_vbase_vtbl_entries for it. But it
9836 might be a lost primary, so just skip down to vid->binfo. */
9838 {
9841 }
9847 }
9849 /* Go through the virtual bases, adding the offsets. */
9851 vbase;
9853 {
9854 tree b;
9855 tree delta;
9860 /* Find the instance of this virtual base in the complete
9861 object. */
9864 /* If we've already got an offset for this virtual base, we
9865 don't need another one. */
9870 /* Figure out where we can find this vbase offset. */
9879 /* The vbase offset had better be the same. */
9882 /* The next vbase will come at a more negative offset. */
9886 /* The initializer is the delta from BINFO to this virtual base.
9887 The vbase offsets go in reverse inheritance-graph order, and
9888 we are walking in inheritance graph order so these end up in
9889 the right order. */
9896 }
9897 }
9899 /* Adds the initializers for the vcall offset entries in the vtable
9900 for BINFO (which is part of the class hierarchy dominated by VID->DERIVED)
9901 to VID->INITS. */
9903 static void
9905 {
9906 /* We only need these entries if this base is a virtual base. We
9907 compute the indices -- but do not add to the vtable -- when
9908 building the main vtable for a class. */
9911 /* If BINFO is RTTI_BINFO, then (since BINFO does not
9912 correspond to VID->DERIVED), we are building a primary
9913 construction virtual table. Since this is a primary
9914 virtual table, we do not need the vcall offsets for
9915 BINFO. */
9917 {
9918 /* We need a vcall offset for each of the virtual functions in this
9919 vtable. For example:
9921 class A { virtual void f (); };
9922 class B1 : virtual public A { virtual void f (); };
9923 class B2 : virtual public A { virtual void f (); };
9924 class C: public B1, public B2 { virtual void f (); };
9926 A C object has a primary base of B1, which has a primary base of A. A
9927 C also has a secondary base of B2, which no longer has a primary base
9928 of A. So the B2-in-C construction vtable needs a secondary vtable for
9929 A, which will adjust the A* to a B2* to call f. We have no way of
9930 knowing what (or even whether) this offset will be when we define B2,
9931 so we store this "vcall offset" in the A sub-vtable and look it up in
9932 a "virtual thunk" for B2::f.
9934 We need entries for all the functions in our primary vtable and
9935 in our non-virtual bases' secondary vtables. */
9937 /* If we are just computing the vcall indices -- but do not need
9938 the actual entries -- not that. */
9941 /* Now, walk through the non-virtual bases, adding vcall offsets. */
9943 }
9944 }
9946 /* Build vcall offsets, starting with those for BINFO. */
9948 static void
9950 {
9952 tree primary_binfo;
9953 tree base_binfo;
9955 /* Don't walk into virtual bases -- except, of course, for the
9956 virtual base for which we are building vcall offsets. Any
9957 primary virtual base will have already had its offsets generated
9958 through the recursion in build_vcall_and_vbase_vtbl_entries. */
9962 /* If BINFO has a primary base, process it first. */
9967 /* Add BINFO itself to the list. */
9970 /* Scan the non-primary bases of BINFO. */
9974 }
9976 /* Called from build_vcall_offset_vtbl_entries_r. */
9978 static void
9980 {
9981 /* Make entries for the rest of the virtuals. */
9982 tree orig_fn;
9984 /* The ABI requires that the methods be processed in declaration
9985 order. */
9987 orig_fn;
9991 }
9993 /* Add a vcall offset entry for ORIG_FN to the vtable. */
9995 static void
9997 {
9999 tree vcall_offset;
10000 tree derived_entry;
10002 /* If there is already an entry for a function with the same
10003 signature as FN, then we do not need a second vcall offset.
10004 Check the list of functions already present in the derived
10005 class vtable. */
10007 {
10009 /* We only use one vcall offset for virtual destructors,
10010 even though there are two virtual table entries. */
10014 }
10016 /* If we are building these vcall offsets as part of building
10017 the vtable for the most derived class, remember the vcall
10018 offset. */
10020 {
10023 }
10025 /* The next vcall offset will be found at a more negative
10026 offset. */
10030 /* Keep track of this function. */
10034 {
10035 tree base;
10036 tree fn;
10038 /* Find the overriding function. */
10042 else
10043 {
10046 /* The vbase we're working on is a primary base of
10047 vid->binfo. But it might be a lost primary, so its
10048 BINFO_OFFSET might be wrong, so we just use the
10049 BINFO_OFFSET from vid->binfo. */
10055 vcall_offset);
10056 }
10057 /* Add the initializer to the vtable. */
10059 }
10060 }
10062 /* Return vtbl initializers for the RTTI entries corresponding to the
10063 BINFO's vtable. The RTTI entries should indicate the object given
10064 by VID->rtti_binfo. */
10066 static void
10068 {
10069 tree b;
10070 tree t;
10071 tree offset;
10072 tree decl;
10073 tree init;
10077 /* To find the complete object, we will first convert to our most
10078 primary base, and then add the offset in the vtbl to that value. */
10083 /* The second entry is the address of the typeinfo object. */
10086 else
10089 /* Convert the declaration to a type that can be stored in the
10090 vtable. */
10094 /* Add the offset-to-top entry. It comes earlier in the vtable than
10095 the typeinfo entry. Convert the offset to look like a
10096 function pointer, so that we can put it in the vtable. */
10099 }
10101 /* TRUE iff TYPE is uniquely derived from PARENT. Ignores
10102 accessibility. */
10104 bool
10106 {
10109 }
10111 /* TRUE iff TYPE is publicly & uniquely derived from PARENT. */
10113 bool
10115 {
10119 }
10121 /* CTX1 and CTX2 are declaration contexts. Return the innermost common
10122 class between them, if any. */
10124 tree
10126 {
10138 {
10141 }
10145 }