| blob | bc0db0000deb049186441aaa0d73d26a52f1849f |
1 /* Process declarations and variables for C++ compiler.
2 Copyright (C) 1988-2017 Free Software Foundation, Inc.
3 Hacked 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 /* Process declarations and symbol lookup for C++ front end.
23 Also constructs types; the standard scalar types at initialization,
24 and structure, union, array and enum types when they are declared. */
26 /* ??? not all decl nodes are given the most useful possible
27 line numbers. For example, the CONST_DECLs for enum values. */
52 /* Id for dumping the raw trees. */
57 /* This structure contains information about the initializations
58 and/or destructions required for a particular priority level. */
60 /* Nonzero if there have been any initializations at this priority
61 throughout the translation unit. */
63 /* Nonzero if there have been any destructions at this priority
64 throughout the translation unit. */
88 /* A list of static class variables. This is needed, because a
89 static class variable can be declared inside the class without
90 an initializer, and then initialized, statically, outside the class. */
93 /* A list of functions which were declared inline, but which we
94 may need to emit outline anyway. */
97 /* A list of decls that use types with no linkage, which we need to make
98 sure are defined. */
101 /* A vector of alternating decls and identifiers, where the latter
102 is to be an alias for the former if the former is defined. */
105 /* hash traits for declarations. Hashes single decls via
106 DECL_ASSEMBLER_NAME_RAW. */
109 {
114 {
116 }
118 {
121 }
127 {
129 }
131 {
133 }
134 };
136 /* A hash table of decls keyed by mangled name. Used to figure out if
137 we need compatibility aliases. */
140 /* Nonzero if we're done parsing and into end-of-file activities. */
144 /* True if note_mangling_alias should enqueue mangling aliases for
145 later generation, rather than emitting them right away. */
148 \f
150 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a
151 FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers
152 that apply to the function). */
154 tree
156 cp_ref_qualifier rqual)
157 {
158 tree raises;
159 tree attrs;
188 }
190 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its
191 return type changed to NEW_RET. */
193 tree
195 {
196 tree newtype;
209 {
214 }
215 else
216 newtype = build_method_type_directly
228 }
230 /* Build a PARM_DECL of FN with NAME and TYPE, and set DECL_ARG_TYPE
231 appropriately. */
233 tree
235 {
240 /* DECL_ARG_TYPE is only used by the back end and the back end never
241 sees templates. */
246 }
248 /* Returns a PARM_DECL of FN for a parameter of the indicated TYPE, with the
249 indicated NAME. */
251 tree
253 {
256 /* All our artificial parms are implicitly `const'; they cannot be
257 assigned to. */
260 }
262 /* Constructors for types with virtual baseclasses need an "in-charge" flag
263 saying whether this constructor is responsible for initialization of
264 virtual baseclasses or not. All destructors also need this "in-charge"
265 flag, which additionally determines whether or not the destructor should
266 free the memory for the object.
268 This function adds the "in-charge" flag to member function FN if
269 appropriate. It is called from grokclassfn and tsubst.
270 FN must be either a constructor or destructor.
272 The in-charge flag follows the 'this' parameter, and is followed by the
273 VTT parm (if any), then the user-written parms. */
275 void
277 {
280 /* If we've already add the in-charge parameter don't do it again. */
284 /* When processing templates we can't know, in general, whether or
285 not we're going to have virtual baseclasses. */
289 /* We don't need an in-charge parameter for constructors that don't
290 have virtual bases. */
301 /* If this is a subobject constructor or destructor, our caller will
302 pass us a pointer to our VTT. */
304 {
307 /* First add it to DECL_ARGUMENTS between 'this' and the real args... */
311 /* ...and then to TYPE_ARG_TYPES. */
315 }
317 /* Then add the in-charge parm (before the VTT parm). */
323 /* Insert our new parameter(s) into the list. */
326 /* And rebuild the function type. */
328 arg_types);
333 fntype = (cp_build_type_attribute_variant
337 /* Now we've got the in-charge parameter. */
339 }
341 /* Classes overload their constituent function names automatically.
342 When a function name is declared in a record structure,
343 its name is changed to it overloaded name. Since names for
344 constructors and destructors can conflict, we place a leading
345 '$' for destructors.
347 CNAME is the name of the class we are grokking for.
349 FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'.
351 FLAGS contains bits saying what's special about today's
352 arguments. DTOR_FLAG == DESTRUCTOR.
354 If FUNCTION is a destructor, then we must add the `auto-delete' field
355 as a second parameter. There is some hair associated with the fact
356 that we must "declare" this variable in the manner consistent with the
357 way the rest of the arguments were declared.
359 QUALS are the qualifiers for the this pointer. */
361 void
363 {
366 /* Even within an `extern "C"' block, members get C++ linkage. See
367 [dcl.link] for details. */
371 {
375 }
384 }
386 /* Create an ARRAY_REF, checking for the user doing things backwards
387 along the way. DECLTYPE_P is for N3276, as in the parser. */
389 tree
392 {
393 tree type;
394 tree expr;
403 {
410 }
416 /* If they have an `operator[]', use that. */
418 {
424 }
425 else
426 {
429 /* Otherwise, create an ARRAY_REF for a pointer or array type.
430 It is a little-known fact that, if `a' is an array and `i' is
431 an int, you can write `i[a]', which means the same thing as
432 `a[i]'. */
435 else
440 else
455 else
456 {
460 }
467 else
471 }
473 {
480 }
482 }
484 /* Given the cast expression EXP, checking out its validity. Either return
485 an error_mark_node if there was an unavoidable error, return a cast to
486 void for trying to delete a pointer w/ the value 0, or return the
487 call to delete. If DOING_VEC is true, we handle things differently
488 for doing an array delete.
489 Implements ARM $5.3.4. This is called from the parser. */
491 tree
493 tsubst_flags_t complain)
494 {
501 {
507 }
509 /* An array can't have been allocated by new, so complain. */
516 {
520 }
524 /* As of Valley Forge, you can delete a pointer to const. */
526 /* You can't delete functions. */
528 {
532 }
534 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */
536 {
539 }
541 /* Deleting a pointer with the value zero is valid and has no effect. */
547 sfk_deleting_destructor,
549 else
552 complain);
553 }
555 /* Report an error if the indicated template declaration is not the
556 sort of thing that should be a member template. */
558 void
560 {
561 tree decl;
570 {
571 /* The parser rejects template declarations in local classes
572 (with the exception of generic lambdas). */
574 /* The parser rejects any use of virtual in a function template. */
578 /* The debug-information generating code doesn't know what to do
579 with member templates. */
581 }
584 else
586 }
588 /* Sanity check: report error if this function FUNCTION is not
589 really a member of the class (CTYPE) it is supposed to belong to.
590 TEMPLATE_PARMS is used to specify the template parameters of a member
591 template passed as FUNCTION_DECL. If the member template is passed as a
592 TEMPLATE_DECL, it can be NULL since the parameters can be extracted
593 from the declaration. If the function is not a function template, it
594 must be NULL.
595 It returns the original declaration for the function, NULL_TREE if
596 no declaration was found, error_mark_node if an error was emitted. */
598 tree
600 {
605 /* Since this is a specialization of a member template,
606 we're not going to find the declaration in the class.
607 For example, in:
609 struct S { template <typename T> void f(T); };
610 template <> void S::f(int);
612 we're not going to find `S::f(int)', but there's no
613 reason we should, either. We let our callers know we didn't
614 find the method, but we don't complain. */
617 /* Basic sanity check: for a template function, the template parameters
618 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */
620 {
624 {
628 }
630 }
632 /* OK, is this a definition of a member template? */
635 /* [temp.mem]
637 A destructor shall not be a member template. */
639 {
642 }
644 /* We must enter the scope here, because conversion operators are
645 named by target type, and type equivalence relies on typenames
646 resolving within the scope of CTYPE. */
652 {
655 /* A member template definition only matches a member template
656 declaration. */
666 /* We cannot simply call decls_match because this doesn't work
667 for static member functions that are pretending to be
668 methods, and because the name may have been changed by
669 asm("new_name"). */
671 /* Get rid of the this parameter on functions that become
672 static. */
677 /* ref-qualifier or absence of same must match. */
682 // Include constraints in the match.
686 /* While finding a match, same types and params are not enough
687 if the function is versioned. Also check version ("target")
688 attributes. */
693 && (!is_template
702 }
705 {
708 else
709 {
720 else
725 }
727 }
733 }
735 /* DECL is a function with vague linkage. Remember it so that at the
736 end of the translation unit we can decide whether or not to emit
737 it. */
739 void
741 {
744 }
746 /* As above, but for variable template instantiations. */
748 void
750 {
752 }
754 /* We have just processed the DECL, which is a static data member.
755 The other parameters are as for cp_finish_decl. */
757 void
760 tree asmspec_tree,
762 {
765 /* We cannot call pushdecl here, because that would fill in the
766 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do
767 the right thing, namely, to put this decl out straight away. */
773 /* We already complained about the template definition. */
777 else
781 {
787 }
796 {
797 /* Similarly to start_decl_1, we want to complete the type in order
798 to do the right thing in cp_apply_type_quals_to_decl, possibly
799 clear TYPE_QUAL_CONST (c++/65579). */
802 }
805 }
807 /* DECLARATOR and DECLSPECS correspond to a class member. The other
808 parameters are as for cp_finish_decl. Return the DECL for the
809 class member declared. */
811 tree
815 tree asmspec_tree,
816 tree attrlist)
817 {
818 tree value;
821 tree name;
831 /* friend or constructor went bad. */
837 {
840 }
842 /* Pass friendly classes back. */
850 {
852 {
855 }
860 value);
861 }
863 /* Stash away type declarations. */
865 {
870 {
873 /* If this is a typedef that names the class for linkage purposes
874 (7.1.3p8), apply any attributes directly to the type. */
880 }
887 /* It's important that push_template_decl below follows
888 set_underlying_type above so that the created template
889 carries the properly set type of VALUE. */
895 }
900 {
903 }
909 {
911 {
913 {
917 }
919 {
921 {
925 }
926 }
930 {
935 else
937 value);
938 }
939 else
940 {
944 value);
945 else
947 value);
948 }
949 }
954 }
956 /* Pass friend decls back. */
962 /* Need to set this before push_template_decl. */
967 {
971 }
978 else
982 {
1007 /* Pass friends back this way. */
1016 }
1018 }
1020 /* Like `grokfield', but for bitfields.
1021 WIDTH is the width of the bitfield, a constant expression.
1022 The other parameters are as for grokfield. */
1024 tree
1027 tree attrlist)
1028 {
1037 /* Pass friendly classes back. */
1044 {
1047 }
1050 {
1053 }
1055 /* Usually, finish_struct_1 catches bitfields with invalid types.
1056 But, in the case of bitfields with function type, we confuse
1057 ourselves into thinking they are member functions, so we must
1058 check here. */
1060 {
1064 }
1067 {
1071 }
1074 {
1078 }
1081 {
1084 }
1092 {
1093 /* The width must be an integer type. */
1098 else
1099 {
1100 /* Temporarily stash the width in DECL_BIT_FIELD_REPRESENTATIVE.
1101 check_bitfield_decl picks it from there later and sets DECL_SIZE
1102 accordingly. */
1105 }
1106 }
1114 }
1116 \f
1117 /* Returns true iff ATTR is an attribute which needs to be applied at
1118 instantiation time rather than template definition time. */
1120 static bool
1122 {
1126 tree arg;
1129 /* Unknown attribute. */
1132 /* Attribute weak handling wants to write out assembly right away. */
1136 /* Attributes used and unused are applied directly, as they appertain to
1137 decls. */
1142 /* Attribute tls_model wants to modify the symtab. */
1146 /* #pragma omp declare simd attribute needs to be always deferred. */
1151 /* An attribute pack is clearly dependent. */
1155 /* If any of the arguments are dependent expressions, we can't evaluate
1156 the attribute until instantiation time. */
1158 {
1161 /* If the first attribute argument is an identifier, only consider
1162 second and following arguments. Attributes like mode, format,
1163 cleanup and several target specific attributes aren't late
1164 just because they have an IDENTIFIER_NODE as first argument. */
1172 }
1177 {
1180 /* We can't apply any attributes to a completely unknown type until
1181 instantiation time. */
1187 /* Also defer most attributes on dependent types. This is not
1188 necessary in all cases, but is the better default. */
1190 /* But some attributes specifically apply to templates. */
1195 else
1197 }
1198 else
1200 }
1202 /* ATTR_P is a list of attributes. Remove any attributes which need to be
1203 applied at instantiation time and return them. If IS_DEPENDENT is true,
1204 the declaration itself is dependent, so all attributes should be applied
1205 at instantiation time. */
1207 static tree
1209 {
1218 {
1220 {
1226 }
1227 else
1229 }
1232 }
1234 /* Remove any late attributes from the list in ATTR_P and attach them to
1235 DECL_P. */
1237 static void
1239 {
1251 else
1256 /* Merge the late attributes at the beginning with the attribute
1257 list. */
1262 {
1263 /* We've added new attributes directly to the main variant, so
1264 now we need to update all of the other variants to include
1265 these new attributes. */
1266 tree variant;
1269 {
1272 }
1273 }
1274 }
1276 /* True if ATTRS contains any dependent attributes that affect type
1277 identity. */
1279 bool
1281 {
1284 {
1288 }
1290 }
1292 /* Return true iff ATTRS are acceptable attributes to be applied in-place
1293 to a typedef which gives a previously unnamed class or enum a name for
1294 linkage purposes. */
1296 bool
1298 {
1300 {
1304 }
1306 }
1308 /* Like reconstruct_complex_type, but handle also template trees. */
1310 tree
1312 {
1317 {
1321 }
1323 {
1327 }
1329 {
1332 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the
1333 element type qualification will be handled by the recursive
1334 cp_reconstruct_complex_type call and cp_build_qualified_type
1335 for ARRAY_TYPEs changes the element type. */
1337 }
1339 {
1346 }
1348 {
1351 /* The build_method_type_directly() routine prepends 'this' to argument list,
1352 so we must compensate by getting rid of it. */
1353 outer
1354 = build_method_type_directly
1357 }
1359 {
1362 }
1363 else
1374 }
1376 /* Replaces any constexpr expression that may be into the attributes
1377 arguments with their reduced value. */
1379 static void
1381 {
1385 tree attr;
1387 {
1388 tree arg;
1390 {
1394 }
1395 }
1396 }
1398 /* Return true if TYPE is an OpenMP mappable type. */
1399 bool
1401 {
1402 /* Mappable type has to be complete. */
1405 /* Arrays have mappable type if the elements have mappable type. */
1408 /* A mappable type cannot contain virtual members. */
1411 /* All data members must be non-static. */
1413 {
1414 tree field;
1418 /* All fields must have mappable types. */
1422 }
1424 }
1426 /* Like decl_attributes, but handle C++ complexity. */
1428 void
1430 {
1435 /* Add implicit "omp declare target" attribute if requested. */
1440 {
1450 else
1453 }
1456 {
1461 }
1469 {
1470 attributes
1474 }
1475 else
1481 /* Propagate deprecation out to the template. */
1484 {
1490 }
1491 }
1492 \f
1493 /* Walks through the namespace- or function-scope anonymous union
1494 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1495 Returns one of the fields for use in the mangled name. */
1497 static tree
1499 {
1501 tree field;
1503 /* Rather than write the code to handle the non-union case,
1504 just give an error. */
1506 {
1509 }
1514 {
1515 tree decl;
1516 tree ref;
1521 {
1523 "%q#D invalid; an anonymous union can only "
1526 }
1538 else
1543 {
1544 tree base;
1560 }
1563 else
1568 }
1571 }
1573 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1574 anonymous union, then all members must be laid out together. PUBLIC_P
1575 is nonzero if this union is not declared static. */
1577 void
1579 {
1580 tree type;
1581 tree main_decl;
1590 /* The VAR_DECL's context is the same as the TYPE's context. */
1597 {
1600 }
1606 {
1609 }
1612 {
1613 /* Use main_decl to set the mangled name. */
1619 }
1623 }
1624 \f
1625 /* Auxiliary functions to make type signatures for
1626 `operator new' and `operator delete' correspond to
1627 what compiler will be expecting. */
1629 tree
1631 {
1638 {
1641 }
1644 {
1646 {
1647 /* [basic.stc.dynamic.allocation]
1649 The first parameter shall not have an associated default
1650 argument. */
1653 /* Throw away the default argument. */
1655 }
1658 {
1661 }
1662 }
1663 else
1671 {
1674 /* Fall through. */
1676 type = build_exception_variant
1679 /* Fall through. */
1681 }
1683 }
1685 tree
1687 {
1694 {
1697 }
1701 {
1706 ptr_type_node);
1707 }
1709 {
1712 /* Fall through. */
1714 type = build_exception_variant
1717 /* Fall through. */
1719 }
1722 }
1723 \f
1724 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1725 and mark them as needed. */
1727 static void
1729 {
1730 tree fnaddr;
1733 /* It's OK for the vtable to refer to deprecated virtual functions. */
1738 {
1739 tree fn;
1745 /* This entry is an offset: a virtual base class offset, a
1746 virtual call offset, an RTTI offset, etc. */
1751 /* When we don't have vcall offsets, we output thunks whenever
1752 we output the vtables that contain them. With vcall offsets,
1753 we know all the thunks we'll need when we emit a virtual
1754 function, so we emit the thunks there instead. */
1758 }
1759 }
1761 /* Set DECL up to have the closest approximation of "initialized common"
1762 linkage available. */
1764 void
1766 {
1771 /* We can just emit function and compiler-generated variables
1772 statically; having multiple copies is (for the most part) only
1773 a waste of space.
1775 There are two correctness issues, however: the address of a
1776 template instantiation with external linkage should be the
1777 same, independent of what translation unit asks for the
1778 address, and this will not hold when we emit multiple copies of
1779 the function. However, there's little else we can do.
1781 Also, by default, the typeinfo implementation assumes that
1782 there will be only one copy of the string used as the name for
1783 each type. Therefore, if weak symbols are unavailable, the
1784 run-time library should perform a more conservative check; it
1785 should perform a string comparison, rather than an address
1786 comparison. */
1788 else
1789 {
1790 /* Static data member template instantiations, however, cannot
1791 have multiple copies. */
1796 {
1799 }
1801 {
1802 /* We can't do anything useful; leave vars for explicit
1803 instantiation. */
1806 }
1807 }
1811 }
1813 /* For win32 we also want to put explicit instantiations in
1814 linkonce sections, so that they will be merged with implicit
1815 instantiations; otherwise we get duplicate symbol errors.
1816 For Darwin we do not want explicit instantiations to be
1817 linkonce. */
1819 void
1821 {
1822 /* We used to say that this was not necessary on targets that support weak
1823 symbols, because the implicit instantiations will defer to the explicit
1824 one. However, that's not actually the case in SVR4; a strong definition
1825 after a weak one is an error. Also, not making explicit
1826 instantiations one_only means that we can end up with two copies of
1827 some template instantiations. */
1831 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1832 we can get away with not emitting them if they aren't used. We need
1833 to for variables so that cp_finish_decl will update their linkage,
1834 because their DECL_INITIAL may not have been set properly yet. */
1839 {
1843 {
1846 /* Mark it needed so we don't forget to emit it. */
1849 }
1850 }
1851 }
1853 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1854 This predicate will give the right answer during parsing of the
1855 function, which other tests may not. */
1857 bool
1859 {
1861 {
1862 /* maybe_thunk_body clears TREE_PUBLIC on the maybe-in-charge 'tor
1863 variants, check one of the "clones" for the real linkage. */
1872 }
1873 /* Unfortunately, import_export_decl has not always been called
1874 before the function is processed, so we cannot simply check
1875 DECL_COMDAT. */
1884 /* A local static in an inline effectively has vague linkage. */
1887 else
1889 }
1891 /* Determine whether or not we want to specifically import or export CTYPE,
1892 using various heuristics. */
1894 static void
1896 {
1897 /* -1 for imported, 1 for exported. */
1900 /* It only makes sense to call this function at EOF. The reason is
1901 that this function looks at whether or not the first non-inline
1902 non-abstract virtual member function has been defined in this
1903 translation unit. But, we can't possibly know that until we've
1904 seen the entire translation unit. */
1910 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1911 we will have CLASSTYPE_INTERFACE_ONLY set but not
1912 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1913 heuristic because someone will supply a #pragma implementation
1914 elsewhere, and deducing it here would produce a conflict. */
1924 /* For a template class, without -fimplicit-templates, check the
1925 repository. If the virtual table is assigned to this
1926 translation unit, then export the class; otherwise, import
1927 it. */
1930 {
1931 /* The ABI specifies that the virtual table and associated
1932 information are emitted with the key method, if any. */
1934 /* If weak symbol support is not available, then we must be
1935 careful not to emit the vtable when the key function is
1936 inline. An inline function can be defined in multiple
1937 translation units. If we were to emit the vtable in each
1938 translation unit containing a definition, we would get
1939 multiple definition errors at link-time. */
1942 }
1944 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1945 a definition anywhere else. */
1949 /* Allow back ends the chance to overrule the decision. */
1954 {
1957 }
1958 }
1960 /* Return true if VAR has already been provided to the back end; in that
1961 case VAR should not be modified further by the front end. */
1962 static bool
1964 {
1966 }
1968 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1969 must be emitted in this translation unit. Mark it as such. */
1971 void
1973 {
1976 {
1977 /* Extern inline functions don't become needed when referenced.
1978 If we know a method will be emitted in other TU and no new
1979 functions can be marked reachable, just use the external
1980 definition. */
1984 /* #pragma interface and -frepo code can call mark_needed for
1985 maybe-in-charge 'tors; mark the clones as well. */
1986 tree clone;
1989 }
1991 {
1993 /* C++ frontend use mark_decl_references to force COMDAT variables
1994 to be output that might appear dead otherwise. */
1996 }
1997 }
1999 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
2000 returns true if a definition of this entity should be provided in
2001 this object file. Callers use this function to determine whether
2002 or not to let the back end know that a definition of DECL is
2003 available in this translation unit. */
2005 bool
2007 {
2009 /* This function should only be called at the end of the translation
2010 unit. We cannot be sure of whether or not something will be
2011 COMDAT until that point. */
2014 /* All entities with external linkage that are not COMDAT/EXTERN should be
2015 emitted; they may be referred to from other object files. */
2018 /* Functions marked "dllexport" must be emitted so that they are
2019 visible to other DLLs. */
2024 /* When not optimizing, do not bother to produce definitions for extern
2025 symbols. */
2034 /* If this entity was used, let the back end see it; it will decide
2035 whether or not to emit it into the object file. */
2039 /* Virtual functions might be needed for devirtualization. */
2045 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
2046 reference to DECL might cause it to be emitted later. */
2048 }
2050 /* If necessary, write out the vtables for the dynamic class CTYPE.
2051 Returns true if any vtables were emitted. */
2053 static bool
2055 {
2056 tree vtbl;
2057 tree primary_vtbl;
2061 /* If the vtables for this class have already been emitted there is
2062 nothing more to do. */
2066 /* Ignore dummy vtables made by get_vtable_decl. */
2070 /* On some targets, we cannot determine the key method until the end
2071 of the translation unit -- which is when this function is
2072 called. */
2076 /* See if any of the vtables are needed. */
2078 {
2082 }
2084 {
2085 /* If the references to this class' vtables are optimized away,
2086 still emit the appropriate debugging information. See
2087 dfs_debug_mark. */
2092 }
2094 /* The ABI requires that we emit all of the vtables if we emit any
2095 of them. */
2097 {
2098 /* Mark entities references from the virtual table as used. */
2102 {
2105 LOOKUP_NORMAL);
2107 /* It had better be all done at compile-time. */
2109 }
2111 /* Write it out. */
2115 /* Because we're only doing syntax-checking, we'll never end up
2116 actually marking the variable as written. */
2120 {
2125 }
2126 }
2128 /* Since we're writing out the vtable here, also write the debug
2129 info. */
2133 }
2135 /* A special return value from type_visibility meaning internal
2136 linkage. */
2140 /* walk_tree helper function for type_visibility. */
2142 static tree
2144 {
2147 {
2149 }
2152 {
2155 }
2160 }
2162 /* Returns the visibility of TYPE, which is the minimum visibility of its
2163 component types. */
2165 static int
2167 {
2171 }
2173 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2174 specified (or if VISIBILITY is static). If TMPL is true, this
2175 constraint is for a template argument, and takes precedence
2176 over explicitly-specified visibility on the template. */
2178 static void
2180 {
2182 {
2183 /* extern "C" declarations aren't affected by the anonymous
2184 namespace. */
2186 {
2192 {
2197 }
2201 }
2202 }
2205 {
2207 /* This visibility was not specified. */
2209 }
2210 }
2212 /* Constrain the visibility of DECL based on the visibility of its template
2213 arguments. */
2215 static void
2217 {
2218 /* If this is a template instantiation, check the innermost
2219 template args for visibility constraints. The outer template
2220 args are covered by the class check. */
2224 {
2230 else
2231 {
2239 {
2242 else
2244 }
2245 }
2248 }
2249 }
2251 /* Like c_determine_visibility, but with additional C++-specific
2252 behavior.
2254 Function-scope entities can rely on the function's visibility because
2255 it is set in start_preparsed_function.
2257 Class-scope entities cannot rely on the class's visibility until the end
2258 of the enclosing class definition.
2260 Note that because namespaces have multiple independent definitions,
2261 namespace visibility is handled elsewhere using the #pragma visibility
2262 machinery rather than by decorating the namespace declaration.
2264 The goal is for constraints from the type to give a diagnostic, and
2265 other constraints to be applied silently. */
2267 void
2269 {
2270 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2272 /* Only relevant for names with external linkage. */
2276 /* Cloned constructors and destructors get the same visibility as
2277 the underlying function. That should be set up in
2278 maybe_clone_body. */
2284 /* The decl may be a template instantiation, which could influence
2285 visibilty. */
2288 {
2290 {
2293 }
2296 }
2300 /* If DECL is a member of a class, visibility specifiers on the
2301 class can influence the visibility of the DECL. */
2305 else
2306 {
2307 /* Not a class member. */
2309 /* Virtual tables have DECL_CONTEXT set to their associated class,
2310 so they are automatically handled above. */
2315 {
2316 /* Local statics and classes get the visibility of their
2317 containing function by default, except that
2318 -fvisibility-inlines-hidden doesn't affect them. */
2321 {
2325 }
2326 else
2327 {
2331 {
2335 }
2336 else
2337 {
2341 }
2342 }
2344 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2345 but have no TEMPLATE_INFO. Their containing template
2346 function does, and the local class could be constrained
2347 by that. */
2350 }
2353 {
2354 /* Under -fvisibility-ms-compat, types are visible by default,
2355 even though their contents aren't. */
2362 else
2364 }
2366 {
2367 /* tinfo visibility is based on the type it's for. */
2368 constrain_visibility
2371 /* Give the target a chance to override the visibility associated
2372 with DECL. */
2378 }
2380 /* Template instantiations and specializations get visibility based
2383 {
2386 else
2387 {
2388 /* Set default visibility to whatever the user supplied with
2389 #pragma GCC visibility or a namespace visibility attribute. */
2392 }
2393 }
2394 }
2397 {
2398 /* If the specialization doesn't specify visibility, use the
2399 visibility from the template. */
2407 {
2411 {
2415 else
2416 {
2420 }
2421 }
2424 /* Template argument visibility outweighs #pragma or namespace
2425 visibility, but not an explicit attribute. */
2427 {
2430 {
2431 /* A class template member with explicit visibility
2432 overrides the class visibility, so we need to apply
2433 all the levels of template args directly. */
2436 {
2439 }
2440 }
2442 /* Limit visibility based on its template arguments. */
2444 }
2445 }
2446 }
2452 /* Names in an anonymous namespace get internal linkage.
2453 This might change once we implement export. */
2456 {
2457 /* Propagate anonymity from type to decl. */
2462 }
2464 /* DR 757: A type without linkage shall not be used as the type of a
2465 variable or function with linkage, unless
2466 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2467 o the variable or function is not used (3.2 [basic.def.odr]) or is
2468 defined in the same translation unit.
2470 Since non-extern "C" decls need to be defined in the same
2471 translation unit, we can make the type internal. */
2474 /* If visibility changed and DECL already has DECL_RTL, ensure
2475 symbol flags are updated. */
2482 }
2484 /* By default, static data members and function members receive
2485 the visibility of their containing class. */
2487 static void
2489 {
2495 else
2496 {
2497 /* Default to the class visibility. */
2501 }
2503 /* Give the target a chance to override the visibility associated
2504 with DECL. */
2508 /* Construction virtual tables are not exported because
2509 they cannot be referred to from other object files;
2510 their name is not standardized by the ABI. */
2516 }
2518 /* Returns true iff DECL is an inline that should get hidden visibility
2519 because of -fvisibility-inlines-hidden. */
2521 static bool
2523 {
2525 /* Don't do this for inline templates; specializations might not be
2526 inline, and we don't want them to inherit the hidden
2527 visibility. We'll set it here for all inline instantiations. */
2528 && !processing_template_decl
2533 }
2535 /* Constrain the visibility of a class TYPE based on the visibility of its
2536 field types. Warn if any fields require lesser visibility. */
2538 void
2540 {
2541 tree binfo;
2542 tree t;
2551 /* Don't warn about visibility if the class has explicit visibility. */
2557 {
2562 {
2564 {
2567 {
2572 else
2576 }
2577 else
2581 }
2582 }
2589 }
2593 {
2597 {
2599 {
2602 {
2607 else
2611 }
2612 else
2616 }
2617 }
2623 }
2624 }
2626 /* Functions for adjusting the visibility of a tagged type and its nested
2627 types and declarations when it gets a name for linkage purposes from a
2628 typedef. */
2633 /* First reset the visibility of all the types. */
2635 static void
2637 {
2642 }
2643 static void
2645 {
2647 }
2649 /* Then reset the visibility of any static data members or member
2650 functions that use those types. */
2652 static void
2654 {
2663 }
2665 static void
2667 {
2669 {
2671 {
2676 }
2678 {
2684 }
2686 {
2690 }
2693 }
2694 }
2696 static void
2698 {
2700 }
2701 void
2703 {
2706 }
2708 /* Set up our initial idea of what the linkage of DECL should be. */
2710 void
2712 {
2714 /* We've already made a decision as to how this function will
2717 {
2720 {
2724 /* A non-template inline function with external linkage will
2725 always be COMDAT. As we must eventually determine the
2726 linkage of all functions, and as that causes writes to
2727 the data mapped in from the PCH file, it's advantageous
2728 to mark the functions at this point. */
2732 {
2733 /* This function must have external linkage, as
2734 otherwise DECL_INTERFACE_KNOWN would have been
2735 set. */
2739 }
2740 }
2743 }
2744 }
2746 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2747 for DECL has not already been determined, do so now by setting
2748 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2749 function is called entities with vague linkage whose definitions
2750 are available must have TREE_PUBLIC set.
2752 If this function decides to place DECL in COMDAT, it will set
2753 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2754 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2755 callers defer that decision until it is clear that DECL is actually
2756 required. */
2758 void
2760 {
2769 /* We cannot determine what linkage to give to an entity with vague
2770 linkage until the end of the file. For example, a virtual table
2771 for a class will be defined if and only if the key method is
2772 defined in this translation unit. As a further example, consider
2773 that when compiling a translation unit that uses PCH file with
2774 "-frepo" it would be incorrect to make decisions about what
2775 entities to emit when building the PCH; those decisions must be
2776 delayed until the repository information has been processed. */
2778 /* Object file linkage for explicit instantiations is handled in
2779 mark_decl_instantiated. For static variables in functions with
2780 vague linkage, maybe_commonize_var is used.
2782 Therefore, the only declarations that should be provided to this
2783 function are those with external linkage that are:
2785 * implicit instantiations of function templates
2787 * inline function
2789 * implicit instantiations of static data members of class
2790 templates
2792 * virtual tables
2794 * typeinfo objects
2796 Furthermore, all entities that reach this point must have a
2797 definition available in this translation unit.
2799 The following assertions check these conditions. */
2801 /* Any code that creates entities with TREE_PUBLIC cleared should
2802 also set DECL_INTERFACE_KNOWN. */
2808 else
2812 /* Check that a definition of DECL is available in this translation
2813 unit. */
2816 /* Assume that DECL will not have COMDAT linkage. */
2818 /* Assume that DECL will not be imported into this translation
2819 unit. */
2822 /* See if the repository tells us whether or not to emit DECL in
2823 this translation unit. */
2828 {
2829 /* The repository indicates that this entity should be defined
2830 here. Make sure the back end honors that request. */
2832 /* Output the definition as an ordinary strong definition. */
2836 }
2839 /* We have already decided what to do with this DECL; there is no
2840 need to check anything further. */
2841 ;
2843 {
2853 /* The ABI requires that all virtual tables be emitted with
2854 COMDAT linkage. However, on systems where COMDAT symbols
2855 don't show up in the table of contents for a static
2856 archive, or on systems without weak symbols (where we
2857 approximate COMDAT linkage by using internal linkage), the
2858 linker will report errors about undefined symbols because
2859 it will not see the virtual table definition. Therefore,
2860 in the case that we know that the virtual table will be
2861 emitted in only one translation unit, we make the virtual
2862 table an ordinary definition with external linkage. */
2865 {
2866 /* CLASS_TYPE is being exported from this translation unit,
2867 so DECL should be defined here. */
2869 /* If a class is declared in a header with the "extern
2870 template" extension, then it will not be instantiated,
2871 even in translation units that would normally require
2872 it. Often such classes are explicitly instantiated in
2873 one translation unit. Therefore, the explicit
2874 instantiation must be made visible to other translation
2875 units. */
2877 else
2878 {
2879 /* The generic C++ ABI says that class data is always
2880 COMDAT, even if there is a key function. Some
2881 variants (e.g., the ARM EABI) says that class data
2882 only has COMDAT linkage if the class data might be
2883 emitted in more than one translation unit. When the
2884 key method can be inline and is inline, we still have
2885 to arrange for comdat even though
2886 class_data_always_comdat is false. */
2890 {
2891 /* The ABI requires COMDAT linkage. Normally, we
2892 only emit COMDAT things when they are needed;
2893 make sure that we realize that this entity is
2894 indeed needed. */
2897 }
2898 }
2899 }
2903 else
2905 }
2907 {
2910 {
2916 /* If -fno-rtti was specified, then we cannot be sure
2917 that RTTI information will be emitted with the
2918 virtual table of the class, so we must emit it
2919 wherever it is used. */
2922 else
2923 {
2926 {
2932 {
2935 }
2936 }
2937 else
2939 }
2940 }
2941 else
2943 }
2945 {
2946 /* DECL is an implicit instantiation of a function or static
2947 data member. */
2950 || (flag_implicit_inline_templates
2954 else
2955 /* If we are not implicitly generating templates, then mark
2956 this entity as undefined in this translation unit. */
2958 }
2960 {
2962 {
2966 {
2970 && ! flag_implement_inlines
2976 /* Always make artificials weak. */
2979 else
2981 }
2982 }
2983 else
2985 }
2986 else
2990 {
2991 /* If we are importing DECL into this translation unit, mark is
2992 an undefined here. */
2995 }
2997 {
2998 /* If we decided to put DECL in COMDAT, mark it accordingly at
2999 this point. */
3001 }
3004 }
3006 /* Return an expression that performs the destruction of DECL, which
3007 must be a VAR_DECL whose type has a non-trivial destructor, or is
3008 an array whose (innermost) elements have a non-trivial destructor. */
3010 tree
3012 {
3016 }
3018 /* Returns the initialization guard variable for the variable DECL,
3019 which has static storage duration. */
3021 tree
3023 {
3024 tree sname;
3025 tree guard;
3030 {
3031 tree guard_type;
3033 /* We use a type that is big enough to contain a mutex as well
3034 as an integer counter. */
3039 /* The guard should have the same linkage as what it guards. */
3057 }
3059 }
3061 /* Return an atomic load of src with the appropriate memory model. */
3063 static tree
3065 {
3080 }
3082 /* Return those bits of the GUARD variable that should be set when the
3083 guarded entity is actually initialized. */
3085 static tree
3087 {
3089 {
3090 /* We only set the first byte of the guard, in order to leave room
3091 for a mutex in the high-order bits. */
3094 guard);
3097 guard);
3099 }
3102 }
3104 /* Return an expression which determines whether or not the GUARD
3105 variable has already been initialized. */
3107 tree
3109 {
3110 tree guard_value;
3114 else
3117 /* Mask off all but the low bit. */
3119 {
3125 tf_warning_or_error);
3126 }
3133 tf_warning_or_error);
3134 }
3136 /* Return an expression which sets the GUARD variable, indicating that
3137 the variable being guarded has been initialized. */
3139 tree
3141 {
3142 tree guard_init;
3144 /* Set the GUARD to one. */
3150 tf_warning_or_error);
3151 }
3153 /* Returns true iff we can tell that VAR does not have a dynamic
3154 initializer. */
3156 static bool
3158 {
3159 /* If it's defined in another TU, we can't tell. */
3162 /* If it has a non-trivial destructor, registering the destructor
3163 counts as dynamic initialization. */
3166 /* If it's in this TU, its initializer has been processed, unless
3167 it's a case of self-initialization, then DECL_INITIALIZED_P is
3168 false while the initializer is handled by finish_id_expression. */
3171 /* If it has no initializer or a constant one, it's not dynamic. */
3174 }
3176 /* Returns true iff VAR is a variable that needs uses to be
3177 wrapped for possible dynamic initialization. */
3179 static bool
3181 {
3187 }
3189 /* Get the FUNCTION_DECL for the shared TLS init function for this
3190 translation unit. */
3192 static tree
3194 {
3198 {
3201 void_list_node));
3207 }
3209 }
3211 /* Get a FUNCTION_DECL for the init function for the thread_local
3212 variable VAR. The init function will be an alias to the function
3213 that initializes all the non-local TLS variables in the translation
3214 unit. The init function is only used by the wrapper function. */
3216 static tree
3218 {
3219 /* Only C++11 TLS vars need this init fn. */
3223 /* If -fno-extern-tls-init, assume that we don't need to call
3224 a tls init function for a variable defined in another TU. */
3228 /* If the variable is internal, or if we can't generate aliases,
3229 call the local init function directly. */
3236 {
3239 void_list_node));
3248 {
3250 /* If the variable is defined somewhere else and might have static
3251 initialization, make the init function a weak reference. */
3257 else
3259 }
3269 }
3271 }
3273 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3274 variable VAR. The wrapper function calls the init function (if any) for
3275 VAR and then returns a reference to VAR. The wrapper function is used
3276 in place of VAR everywhere VAR is mentioned. */
3278 tree
3280 {
3281 /* Only C++11 TLS vars need this wrapper fn. */
3288 {
3289 /* A named rvalue reference is an lvalue, so the wrapper should
3290 always return an lvalue reference. */
3299 /* The wrapper is inline and emitted everywhere var is used. */
3302 {
3304 #ifdef HAVE_GAS_HIDDEN
3305 /* Make the wrapper bind locally; there's no reason to share
3306 the wrapper between multiple shared objects. */
3309 #endif
3310 }
3316 #if 0
3317 /* We want CSE to commonize calls to the wrapper, but marking it as
3318 pure is unsafe since it has side-effects. I guess we need a new
3319 ECF flag even weaker than ECF_PURE. FIXME! */
3321 #endif
3326 }
3328 }
3330 /* At EOF, generate the definition for the TLS wrapper function FN:
3332 T& var_wrapper() {
3333 if (init_fn) init_fn();
3334 return var;
3335 } */
3337 static void
3339 {
3344 /* Only call the init fn if there might be one. */
3346 {
3348 /* If init_fn is a weakref, make sure it exists before calling. */
3350 {
3355 tf_warning_or_error);
3357 }
3361 {
3364 }
3365 }
3366 else
3367 /* If there's no initialization, the wrapper is a constant function. */
3372 }
3374 /* Start the process of running a particular set of global constructors
3375 or destructors. Subroutine of do_[cd]tors. Also called from
3376 vtv_start_verification_constructor_init_function. */
3378 static tree
3380 {
3381 tree body;
3382 tree fndecl;
3385 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3388 {
3391 #ifdef JOINER
3393 #else
3395 #endif
3398 }
3399 else
3405 NULL_TREE));
3410 /* Mark as artificial because it's not explicitly in the user's
3411 source code. */
3414 /* Mark this declaration as used to avoid spurious warnings. */
3417 /* Mark this function as a global constructor or destructor. */
3420 else
3426 }
3428 /* Finish the process of running a particular set of global constructors
3429 or destructors. Subroutine of do_[cd]tors. */
3431 static void
3433 {
3434 tree fn;
3436 /* Finish up. */
3441 {
3444 }
3445 else
3446 {
3449 }
3452 }
3454 /* The names of the parameters to the function created to handle
3455 initializations and destructions for objects with static storage
3456 duration. */
3460 /* The name of the function we create to handle initializations and
3461 destructions for objects with static storage duration. */
3464 /* The declaration for the __INITIALIZE_P argument. */
3467 /* The declaration for the __PRIORITY argument. */
3470 /* The declaration for the static storage duration function. */
3473 /* All the static storage duration functions created in this
3474 translation unit. */
3477 /* A map from priority levels to information about that priority
3478 level. There may be many such levels, so efficient lookup is
3479 important. */
3482 /* Begins the generation of the function that will handle all
3483 initialization and destruction of objects with static storage
3484 duration. The function generated takes two parameters of type
3485 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3486 nonzero, it performs initializations. Otherwise, it performs
3487 destructions. It only performs those initializations or
3488 destructions with the indicated __PRIORITY. The generated function
3489 returns no value.
3491 It is assumed that this function will only be called once per
3492 translation unit. */
3494 static tree
3496 {
3497 tree type;
3498 tree body;
3501 /* Create the identifier for this function. It will be of the form
3502 SSDF_IDENTIFIER_<number>. */
3507 NULL_TREE);
3509 /* Create the FUNCTION_DECL itself. */
3512 type);
3516 /* Put this function in the list of functions to be called from the
3517 static constructors and destructors. */
3519 {
3522 /* Take this opportunity to initialize the map from priority
3523 numbers to information about that priority level. */
3526 /*delete_value_fn=*/
3529 /* We always need to generate functions for the
3530 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3531 priorities later, we'll be sure to find the
3532 DEFAULT_INIT_PRIORITY. */
3534 }
3538 /* Create the argument list. */
3539 initialize_p_decl = cp_build_parm_decl
3542 priority_decl = cp_build_parm_decl
3549 /* Put the function in the global scope. */
3552 /* Start the function itself. This is equivalent to declaring the
3553 function as:
3555 static void __ssdf (int __initialize_p, init __priority_p);
3557 It is static because we only need to call this function from the
3558 various constructor and destructor functions for this module. */
3561 SF_PRE_PARSED);
3563 /* Set up the scope of the outermost block in the function. */
3567 }
3569 /* Finish the generation of the function which performs initialization
3570 and destruction of objects with static storage duration. After
3571 this point, no more such objects can be created. */
3573 static void
3575 {
3576 /* Close out the function. */
3579 }
3581 /* Return the information about the indicated PRIORITY level. If no
3582 code to handle this level has yet been generated, generate the
3583 appropriate prologue. */
3585 static priority_info
3587 {
3588 priority_info pi;
3589 splay_tree_node n;
3594 {
3595 /* Create a new priority information structure, and insert it
3596 into the map. */
3603 }
3604 else
3608 }
3610 /* The effective initialization priority of a DECL. */
3612 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3613 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3614 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3616 /* Whether a DECL needs a guard to protect it against multiple
3617 initialization. */
3619 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3620 || DECL_ONE_ONLY (decl) \
3621 || DECL_WEAK (decl)))
3623 /* Called from one_static_initialization_or_destruction(),
3624 via walk_tree.
3625 Walks the initializer list of a global variable and looks for
3626 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3627 and that have their DECL_CONTEXT() == NULL.
3628 For each such temporary variable, set their DECL_CONTEXT() to
3629 the current function. This is necessary because otherwise
3630 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3631 when trying to refer to a temporary variable that does not have
3632 it's DECL_CONTECT() properly set. */
3633 static tree
3637 {
3641 {
3642 tree var;
3650 }
3653 }
3655 /* Set up to handle the initialization or destruction of DECL. If
3656 INITP is nonzero, we are initializing the variable. Otherwise, we
3657 are destroying it. */
3659 static void
3661 {
3663 tree guard;
3665 /* If we are supposed to destruct and there's a trivial destructor,
3666 nothing has to be done. */
3671 /* Trick the compiler into thinking we are at the file and line
3672 where DECL was declared so that error-messages make sense, and so
3673 that the debugger will show somewhat sensible file and line
3674 information. */
3677 /* Make sure temporary variables in the initialiser all have
3678 their DECL_CONTEXT() set to a value different from NULL_TREE.
3679 This can happen when global variables initializers are built.
3680 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3681 the temporary variables that might have been generated in the
3682 accompanying initializers is NULL_TREE, meaning the variables have been
3683 declared in the global namespace.
3684 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3685 of the temporaries are set to the current function decl. */
3687 fix_temporary_vars_context_r,
3688 NULL);
3690 /* Because of:
3692 [class.access.spec]
3694 Access control for implicit calls to the constructors,
3695 the conversion functions, or the destructor called to
3696 create and destroy a static data member is performed as
3697 if these calls appeared in the scope of the member's
3698 class.
3700 we pretend we are in a static member function of the class of
3701 which the DECL is a member. */
3703 {
3706 }
3708 /* Assume we don't need a guard. */
3710 /* We need a guard if this is an object with external linkage that
3711 might be initialized in more than one place. (For example, a
3712 static data member of a template, when the data member requires
3713 construction.) */
3715 {
3716 tree guard_cond;
3720 /* When using __cxa_atexit, we just check the GUARD as we would
3721 for a local static. */
3723 {
3724 /* When using __cxa_atexit, we never try to destroy
3725 anything from a static destructor. */
3728 }
3729 /* If we don't have __cxa_atexit, then we will be running
3730 destructors from .fini sections, or their equivalents. So,
3731 we need to know how many times we've tried to initialize this
3732 object. We do initializations only if the GUARD is zero,
3733 i.e., if we are the first to initialize the variable. We do
3734 destructions only if the GUARD is one, i.e., if we are the
3735 last to destroy the variable. */
3737 guard_cond
3739 EQ_EXPR,
3741 guard,
3743 tf_warning_or_error),
3744 integer_one_node,
3745 tf_warning_or_error);
3746 else
3747 guard_cond
3749 EQ_EXPR,
3751 guard,
3753 tf_warning_or_error),
3754 integer_zero_node,
3755 tf_warning_or_error);
3759 }
3762 /* If we're using __cxa_atexit, we have not already set the GUARD,
3763 so we must do so now. */
3767 /* Perform the initialization or destruction. */
3769 {
3771 {
3774 {
3778 }
3779 }
3781 /* If we're using __cxa_atexit, register a function that calls the
3782 destructor for the object. */
3785 }
3786 else
3789 /* Finish the guard if-stmt, if necessary. */
3791 {
3794 }
3796 /* Now that we're done with DECL we don't need to pretend to be a
3797 member of its class any longer. */
3800 }
3802 /* Generate code to do the initialization or destruction of the decls in VARS,
3803 a TREE_LIST of VAR_DECL with static storage duration.
3804 Whether initialization or destruction is performed is specified by INITP. */
3806 static void
3808 {
3811 /* Build the outer if-stmt to check for initialization or destruction. */
3815 EQ_EXPR,
3816 initialize_p_decl,
3817 cond,
3818 tf_warning_or_error);
3821 /* To make sure dynamic construction doesn't access globals from other
3822 compilation units where they might not be yet constructed, for
3823 -fsanitize=address insert __asan_before_dynamic_init call that
3824 prevents access to either all global variables that need construction
3825 in other compilation units, or at least those that haven't been
3826 initialized yet. Variables that need dynamic construction in
3827 the current compilation unit are kept accessible. */
3834 tree priority_if_stmt;
3836 priority_info pi;
3838 /* If we don't need a destructor, there's nothing to do. Avoid
3839 creating a possibly empty if-stmt. */
3841 {
3844 }
3846 /* Remember that we had an initialization or finalization at this
3847 priority. */
3852 else
3855 /* Conditionalize this initialization on being in the right priority
3856 and being initializing/finalizing appropriately. */
3859 EQ_EXPR,
3860 priority_decl,
3862 tf_warning_or_error);
3865 /* Process initializers with same priority. */
3869 /* Do one initialization or destruction. */
3873 /* Finish up the priority if-stmt body. */
3879 /* Revert what __asan_before_dynamic_init did by calling
3880 __asan_after_dynamic_init. */
3884 /* Finish up the init/destruct if-stmt body. */
3887 }
3889 /* VARS is a list of variables with static storage duration which may
3890 need initialization and/or finalization. Remove those variables
3891 that don't really need to be initialized or finalized, and return
3892 the resulting list. The order in which the variables appear in
3893 VARS is in reverse order of the order in which they should actually
3894 be initialized. The list we return is in the unreversed order;
3895 i.e., the first variable should be initialized first. */
3897 static tree
3899 {
3904 {
3909 /* Deal gracefully with error. */
3911 {
3914 }
3916 /* The only things that can be initialized are variables. */
3919 /* If this object is not defined, we don't need to do anything
3920 here. */
3922 {
3925 }
3927 /* Also, if the initializer already contains errors, we can bail
3928 out now. */
3931 {
3934 }
3936 /* This variable is going to need initialization and/or
3937 finalization, so we add it to the list. */
3941 }
3944 }
3946 /* Make sure we have told the back end about all the variables in
3947 VARS. */
3949 static void
3951 {
3952 tree v;
3955 {
3958 {
3961 }
3962 }
3963 }
3965 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
3966 (otherwise) that will initialize all global objects with static
3967 storage duration having the indicated PRIORITY. */
3969 static void
3972 {
3974 tree fndecl;
3975 tree body;
3979 /* ??? */
3980 /* Was: locus->line++; */
3982 /* We use `I' to indicate initialization and `D' to indicate
3983 destruction. */
3986 /* We emit the function lazily, to avoid generating empty
3987 global constructors and destructors. */
3990 /* For Objective-C++, we may need to initialize metadata found in this module.
3991 This must be done _before_ any other static initializations. */
3994 {
3997 }
3999 /* Call the static storage duration function with appropriate
4000 arguments. */
4002 {
4003 /* Calls to pure or const functions will expand to nothing. */
4005 {
4006 tree call;
4013 constructor_p),
4015 priority),
4016 NULL_TREE);
4018 }
4019 }
4021 /* Close out the function. */
4024 }
4026 /* Generate constructor and destructor functions for the priority
4027 indicated by N. */
4029 static int
4031 {
4036 /* Generate the functions themselves, but only if they are really
4037 needed. */
4043 /* Keep iterating. */
4045 }
4047 /* Return C++ property of T, based on given operation OP. */
4049 static int
4051 {
4053 {
4055 {
4063 }
4080 }
4081 }
4083 /* Collect source file references recursively, starting from NAMESPC. */
4085 static void
4087 {
4088 /* Iterate over names in this name space. */
4091 ;
4094 else
4096 }
4098 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4099 starting from NAMESPC. */
4101 static void
4103 {
4106 /* Collect decls from this namespace. This will skip
4107 NAMESPACE_DECLs (both aliases and regular, it cannot tell). */
4110 /* Now scan for namespace children, and dump them. */
4114 }
4116 /* Returns true iff there is a definition available for variable or
4117 function DECL. */
4119 bool
4121 {
4124 /* A pending instantiation of a friend temploid is defined. */
4128 else
4129 {
4132 }
4133 }
4135 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4137 [expr.const]
4139 An integral constant-expression can only involve ... const
4140 variables of integral or enumeration types initialized with
4141 constant expressions ...
4143 C++0x also allows constexpr variables and temporaries initialized
4144 with constant expressions. We handle the former here, but the latter
4145 are just folded away in cxx_eval_constant_expression.
4147 The standard does not require that the expression be non-volatile.
4148 G++ implements the proposed correction in DR 457. */
4150 bool
4152 {
4156 /* We don't know if a template static data member is initialized with
4157 a constant expression until we instantiate its initializer. Even
4158 in the case of a constexpr variable, we can't treat it as a
4159 constant until its initializer is complete in case it's used in
4160 its own initializer. */
4163 }
4165 /* Returns true if DECL could be a symbolic constant variable, depending on
4166 its initializer. */
4168 bool
4170 {
4177 /* A proxy isn't constant. */
4184 else
4189 /* We know the initializer, and it isn't constant. */
4191 else
4193 }
4195 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4196 called from grokfndecl and grokvardecl; in all modes it is called from
4197 cp_write_global_declarations. */
4199 void
4201 {
4203 /* In C++11 it's ok if the decl is defined. */
4207 /* The type that got us on no_linkage_decls must have gotten a name for
4210 /* The type might end up having a typedef name for linkage purposes. */
4213 {
4221 /* DRs 132, 319 and 389 seem to indicate types with
4222 no linkage can only be used to declare extern "C"
4223 entities. Since it's not always an error in the
4224 ISO C++ 90 Standard, we only issue a warning. */
4226 "with no linkage used to declare variable %q#D with "
4228 else
4231 decl);
4236 }
4238 {
4241 "%q#D, declared using local type "
4243 }
4247 else
4250 }
4252 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4254 static void
4256 {
4258 }
4260 /* Clear DECL_EXTERNAL for NODE. */
4262 static bool
4264 {
4267 }
4269 /* Build up the function to run dynamic initializers for thread_local
4270 variables in this translation unit and alias the init functions for the
4271 individual variables to it. */
4273 static void
4275 {
4285 boolean_type_node);
4300 tf_warning_or_error);
4303 boolean_true_node,
4304 tf_warning_or_error));
4306 {
4311 /* Output init aliases even with -fno-extern-tls-init. */
4313 {
4317 cgraph_node *alias
4321 }
4322 }
4328 }
4330 /* We're at the end of compilation, so generate any mangling aliases that
4331 we've been saving up, if DECL is going to be output and ID2 isn't
4332 already taken by another declaration. */
4334 static void
4336 {
4340 {
4343 /* Don't create an alias to an unreferenced function. */
4345 }
4347 tree *slot
4349 INSERT);
4351 /* If there's a declaration already using this mangled name,
4352 don't create a compatibility alias that conflicts. */
4367 else
4369 }
4371 /* Note that we might want to emit an alias with the symbol ID2 for DECL at
4372 the end of translation, for compatibility across bugs in the mangling
4373 implementation. */
4375 void
4377 {
4379 {
4382 else
4383 {
4386 }
4387 }
4388 }
4390 /* Emit all mangling aliases that were deferred up to this point. */
4392 void
4394 {
4396 {
4400 }
4402 }
4404 /* Record a mangling of DECL, whose DECL_ASSEMBLER_NAME has just been
4405 set. NEED_WARNING is true if we must warn about collisions. We do
4406 this to spot changes in mangling that may require compatibility
4407 aliases. */
4409 void
4411 {
4417 tree *slot
4419 INSERT);
4421 /* If this is already an alias, remove the alias, because the real
4422 decl takes precedence. */
4426 {
4429 }
4434 {
4441 "a later -fabi-version= (or =0)"
4444 }
4445 }
4447 /* The mangled name of DECL is being forcibly changed to NAME. Remove
4448 any existing knowledge of DECL's mangled name meaning DECL. */
4450 void
4452 {
4459 NO_INSERT))
4461 {
4464 /* If this is an alias, remove it from the symbol table. */
4469 }
4472 }
4474 /* The entire file is now complete. If requested, dump everything
4475 to a file. */
4477 static void
4479 {
4480 dump_flags_t flags;
4482 {
4485 }
4486 }
4490 /* Check the deallocation functions for CODE to see if we want to warn that
4491 only one was defined. */
4493 static void
4495 {
4501 {
4503 /* We're only interested in usual deallocation functions. */
4508 else
4510 }
4517 }
4519 /* Check the global deallocation functions to see if we want to warn about
4520 defining unsized without sized (or vice versa). */
4522 static void
4524 {
4529 }
4531 /* Earlier we left PTRMEM_CST in variable initializers alone so that we could
4532 look them up when evaluating non-type template parameters. Now we need to
4533 lower them to something the back end can understand. */
4535 static void
4537 {
4540 {
4544 }
4545 }
4547 /* This routine is called at the end of compilation.
4548 Its job is to create all the code needed to initialize and
4549 destroy the global aggregates. We do the destruction
4550 first, since that way we only need to reverse the decls once. */
4552 void
4554 {
4555 tree vars;
4560 tree decl;
4565 /* Bad parse errors. Just forget about it. */
4570 /* This is the point to write out a PCH if we're doing that.
4571 In that case we do not want to do anything else. */
4573 {
4574 /* Mangle all symbols at PCH creation time. */
4582 /* Ensure even the callers don't try to finalize the CU. */
4585 }
4592 /* Handle -fdump-ada-spec[-slim] */
4594 {
4597 else
4601 }
4603 /* FIXME - huh? was input_line -= 1;*/
4605 /* We now have to write out all the stuff we put off writing out.
4606 These include:
4608 o Template specializations that we have not yet instantiated,
4609 but which are needed.
4610 o Initialization and destruction for non-local objects with
4611 static storage duration. (Local objects with static storage
4612 duration are initialized when their scope is first entered,
4613 and are cleaned up via atexit.)
4614 o Virtual function tables.
4616 All of these may cause others to be needed. For example,
4617 instantiating one function may cause another to be needed, and
4618 generating the initializer for an object may cause templates to be
4619 instantiated, etc., etc. */
4623 do
4624 {
4625 tree t;
4626 tree decl;
4630 /* If there are templates that we've put off instantiating, do
4631 them now. */
4635 /* Write out virtual tables as required. Writing out the
4636 virtual table for a template class may cause the
4637 instantiation of members of that class. If we write out
4638 vtables then we remove the class from our list so we don't
4639 have to look at it again. */
4643 {
4646 }
4648 /* Write out needed type info variables. We have to be careful
4649 looping through unemitted decls, because emit_tinfo_decl may
4650 cause other variables to be needed. New elements will be
4651 appended, and we remove from the vector those that actually
4652 get emitted. */
4656 {
4659 }
4661 /* The list of objects with static storage duration is built up
4662 in reverse order. We clear STATIC_AGGREGATES so that any new
4663 aggregates added during the initialization of these will be
4664 initialized in the correct order when we next come around the
4665 loop. */
4669 {
4670 /* We need to start a new initialization function each time
4671 through the loop. That's because we need to know which
4672 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4673 isn't computed until a function is finished, and written
4674 out. That's a deficiency in the back end. When this is
4675 fixed, these initialization functions could all become
4676 inline, with resulting performance improvements. */
4677 tree ssdf_body;
4679 /* Set the line and file, so that it is obviously not from
4680 the source file. */
4684 /* Make sure the back end knows about all the variables. */
4687 /* First generate code to do all the initializations. */
4691 /* Then, generate code to do all the destructions. Do these
4692 in reverse order so that the most recently constructed
4693 variable is the first destroyed. If we're using
4694 __cxa_atexit, then we don't need to do this; functions
4695 were registered at initialization time to destroy the
4696 local statics. */
4698 {
4701 }
4702 else
4705 /* Finish up the static storage duration function for this
4706 round. */
4710 /* All those initializations and finalizations might cause
4711 us to need more inline functions, more template
4712 instantiations, etc. */
4714 ssdf_count++;
4715 /* ??? was: locus_at_end_of_parsing.line++; */
4716 }
4718 /* Now do the same for thread_local variables. */
4721 /* Go through the set of inline functions whose bodies have not
4722 been emitted yet. If out-of-line copies of these functions
4723 are required, emit them. */
4725 {
4726 /* Does it need synthesizing? */
4729 {
4730 /* Even though we're already at the top-level, we push
4731 there again. That way, when we pop back a few lines
4732 hence, all of our state is restored. Otherwise,
4733 finish_function doesn't clean things up, and we end
4734 up with CURRENT_FUNCTION_DECL set. */
4736 /* The decl's location will mark where it was first
4737 needed. Save that so synthesize method can indicate
4738 where it was needed from, in case of error */
4743 }
4753 /* We lie to the back end, pretending that some functions
4754 are not defined when they really are. This keeps these
4755 functions from being put out unnecessarily. But, we must
4756 stop lying when the functions are referenced, or if they
4757 are not comdat since they need to be put out now. If
4758 DECL_INTERFACE_KNOWN, then we have already set
4759 DECL_EXTERNAL appropriately, so there's no need to check
4760 again, and we do not want to clear DECL_EXTERNAL if a
4761 previous call to import_export_decl set it.
4763 This is done in a separate for cycle, because if some
4764 deferred function is contained in another deferred
4765 function later in deferred_fns varray,
4766 rest_of_compilation would skip this function and we
4767 really cannot expand the same function twice. */
4772 {
4778 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4779 group, we need to mark all symbols in the same comdat group
4780 that way. */
4788 }
4790 /* If we're going to need to write this function out, and
4791 there's already a body for it, create RTL for it now.
4792 (There might be no body if this is a method we haven't
4793 gotten around to synthesizing yet.) */
4798 {
4799 /* We will output the function; no longer consider it in this
4800 loop. */
4802 /* Generate RTL for this function now that we know we
4803 need it. */
4805 /* If we're compiling -fsyntax-only pretend that this
4806 function has been written out so that we don't try to
4807 expand it again. */
4811 }
4812 }
4817 /* Static data members are just like namespace-scope globals. */
4819 {
4821 /* Don't write it out if we haven't seen a definition. */
4825 /* If this static data member is needed, provide it to the
4826 back end. */
4829 }
4835 retries++;
4836 }
4843 /* All used inline functions must have a definition at this point. */
4845 {
4848 /* If the definition actually was available here, then the
4849 fact that the function was not defined merely represents
4850 that for some reason (use of a template repository,
4851 #pragma interface, etc.) we decided not to emit the
4852 definition here. */
4854 /* Don't complain if the template was defined. */
4858 {
4861 /* Avoid a duplicate warning from check_global_declaration. */
4863 }
4864 }
4866 /* So must decls that use a type with no linkage. */
4872 /* Then, do the Objective-C stuff. This is where all the
4873 Objective-C module stuff gets generated (symtab,
4874 class/protocol/selector lists etc). This must be done after C++
4875 templates, destructors etc. so that selectors used in C++
4876 templates are properly allocated. */
4880 /* We give C linkage to static constructors and destructors. */
4883 /* Generate initialization and destruction functions for all
4884 priorities for which they are required. */
4887 generate_ctor_and_dtor_functions_for_priority,
4890 /* If this is obj-c++ and we need a static init, call
4891 generate_ctor_or_dtor_function. */
4893 DEFAULT_INIT_PRIORITY,
4896 /* We're done with the splay-tree now. */
4900 /* Generate any missing aliases. */
4903 /* We're done with static constructors, so we can go back to "C++"
4904 linkage now. */
4908 {
4912 }
4919 /* The entire file is now complete. If requested, dump everything
4920 to a file. */
4924 {
4927 }
4932 /* Indicate that we're done with front end processing. */
4934 }
4936 /* Perform any post compilation-proper cleanups for the C++ front-end.
4937 This should really go away. No front-end should need to do
4938 anything past the compilation process. */
4940 void
4942 {
4946 {
4947 /* Generate the special constructor initialization function that
4948 calls __VLTRegisterPairs, and give it a very high
4949 initialization priority. This must be done after
4950 finalize_compilation_unit so that we have accurate
4951 information about which vtable will actually be emitted. */
4953 }
4961 }
4963 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
4964 function to call in parse-tree form; it has not yet been
4965 semantically analyzed. ARGS are the arguments to the function.
4966 They have already been semantically analyzed. This may change
4967 ARGS. */
4969 tree
4971 tsubst_flags_t complain)
4972 {
4973 tree orig_fn;
4975 tree expr;
4976 tree object;
4982 {
4991 /* Transform the arguments and add the implicit "this"
4992 parameter. That must be done before the FN is transformed
4993 because we depend on the form of FN. */
4997 {
5001 }
5002 /* Now that the arguments are done, transform FN. */
5004 }
5006 /* A qualified name corresponding to a bound pointer-to-member is
5007 represented as an OFFSET_REF:
5009 struct B { void g(); };
5010 void (B::*p)();
5011 void B::g() { (this->*p)(); } */
5013 {
5017 complain);
5019 }
5023 else
5032 }
5035 void
5037 {
5042 {
5046 {
5049 }
5050 }
5051 }
5053 /* Return true if function DECL can be inlined. This is used to force
5054 instantiation of methods that might be interesting for inlining. */
5055 bool
5057 {
5063 /* When optimizing, we might inline everything when flatten
5064 attribute or heuristics inlining for size or autoinlining
5065 is used. */
5067 }
5069 /* Normally, we can wait until instantiation-time to synthesize DECL.
5070 However, if DECL is a static data member initialized with a constant
5071 or a constexpr function, we need it right now because a reference to
5072 such a data member or a call to such function is not value-dependent.
5073 For a function that uses auto in the return type, we need to instantiate
5074 it to find out its type. For OpenMP user defined reductions, we need
5075 them instantiated for reduction clauses which inline them by hand
5076 directly. */
5078 static void
5080 {
5089 {
5090 /* Instantiating a function will result in garbage collection. We
5091 must treat this situation as if we were within the body of a
5092 function so as to avoid collecting live data only referenced from
5093 the stack (such as overload resolution candidates). */
5098 }
5099 }
5101 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
5102 If DECL is a specialization or implicitly declared class member,
5103 generate the actual definition. Return false if something goes
5104 wrong, true otherwise. */
5106 bool
5108 {
5109 /* If DECL is a BASELINK for a single function, then treat it just
5110 like the DECL for the function. Otherwise, if the BASELINK is
5111 for an overloaded function, we don't know which function was
5112 actually used until after overload resolution. */
5114 {
5119 }
5121 /* Set TREE_USED for the benefit of -Wunused. */
5123 /* And for structured bindings also the underlying decl. */
5133 /* Mark enumeration types as used. */
5143 {
5147 /* We mark a lambda conversion op as deleted if we can't
5148 generate it properly; see maybe_add_lambda_conv_op. */
5151 {
5155 }
5157 }
5163 /* We can only check DECL_ODR_USED on variables or functions with
5164 DECL_LANG_SPECIFIC set, and these are also the only decls that we
5165 might need special handling for. */
5169 {
5174 }
5176 /* We only want to do this processing once. We don't need to keep trying
5177 to instantiate inline templates, because unit-at-a-time will make sure
5178 we get them compiled before functions that want to inline them. */
5182 /* Normally, we can wait until instantiation-time to synthesize DECL.
5183 However, if DECL is a static data member initialized with a constant
5184 or a constexpr function, we need it right now because a reference to
5185 such a data member or a call to such function is not value-dependent.
5186 For a function that uses auto in the return type, we need to instantiate
5187 it to find out its type. For OpenMP user defined reductions, we need
5188 them instantiated for reduction clauses which inline them by hand
5189 directly. */
5195 /* Check this too in case we're within instantiate_non_dependent_expr. */
5204 {
5208 }
5210 /* If we don't need a value, then we don't need to synthesize DECL. */
5218 /* DR 757: A type without linkage shall not be used as the type of a
5219 variable or function with linkage, unless
5220 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5221 o the variable or function is not used (3.2 [basic.def.odr]) or is
5222 defined in the same translation unit. */
5229 {
5231 /* There's no way to define a local extern, and adding it to
5232 the vector interferes with GC, so give an error now. */
5234 else
5236 }
5240 /* Remember it, so we can check it was defined. */
5243 /* Is it a synthesized method that needs to be synthesized? */
5247 /* A function defaulted outside the class is synthesized either by
5248 cp_finish_decl or instantiate_decl. */
5251 {
5252 /* Defer virtual destructors so that thunks get the right
5253 linkage. */
5255 {
5258 }
5260 /* Remember the current location for a function we will end up
5261 synthesizing. Then we can inform the user where it was
5262 required in the case of error. */
5265 /* Synthesizing an implicitly defined member function will result in
5266 garbage collection. We must treat this situation as if we were
5267 within the body of a function so as to avoid collecting live data
5268 on the stack (such as overload resolution candidates).
5270 We could just let cp_write_global_declarations handle synthesizing
5271 this function by adding it to deferred_fns, but doing
5272 it at the use site produces better error messages. */
5276 /* If this is a synthesized method we don't need to
5277 do the instantiation test below. */
5278 }
5284 /* If this is a function or variable that is an instance of some
5285 template, we now know that we will need to actually do the
5286 instantiation. We check that DECL is not an explicit
5287 instantiation because that is not checked in instantiate_decl.
5289 We put off instantiating functions in order to improve compile
5290 times. Maintaining a stack of active functions is expensive,
5291 and the inliner knows to instantiate any functions it might
5292 need. Therefore, we always try to defer instantiation. */
5293 {
5298 }
5301 }
5303 bool
5305 {
5307 }
5309 tree
5311 {
5313 }
5315 tree
5317 {
5318 tree fn;
5326 }