| blob | a4751460e065172821a49d4d0611d54068b2fd42 |
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 /* Nonzero if we're done parsing and into end-of-file activities. */
109 /* True if note_mangling_alias should enqueue mangling aliases for
110 later generation, rather than emitting them right away. */
113 \f
115 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a
116 FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers
117 that apply to the function). */
119 tree
121 cp_ref_qualifier rqual)
122 {
123 tree raises;
124 tree attrs;
153 }
155 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its
156 return type changed to NEW_RET. */
158 tree
160 {
161 tree newtype;
174 {
179 }
180 else
181 newtype = build_method_type_directly
193 }
195 /* Build a PARM_DECL of FN with NAME and TYPE, and set DECL_ARG_TYPE
196 appropriately. */
198 tree
200 {
205 /* DECL_ARG_TYPE is only used by the back end and the back end never
206 sees templates. */
211 }
213 /* Returns a PARM_DECL of FN for a parameter of the indicated TYPE, with the
214 indicated NAME. */
216 tree
218 {
221 /* All our artificial parms are implicitly `const'; they cannot be
222 assigned to. */
225 }
227 /* Constructors for types with virtual baseclasses need an "in-charge" flag
228 saying whether this constructor is responsible for initialization of
229 virtual baseclasses or not. All destructors also need this "in-charge"
230 flag, which additionally determines whether or not the destructor should
231 free the memory for the object.
233 This function adds the "in-charge" flag to member function FN if
234 appropriate. It is called from grokclassfn and tsubst.
235 FN must be either a constructor or destructor.
237 The in-charge flag follows the 'this' parameter, and is followed by the
238 VTT parm (if any), then the user-written parms. */
240 void
242 {
245 /* If we've already add the in-charge parameter don't do it again. */
249 /* When processing templates we can't know, in general, whether or
250 not we're going to have virtual baseclasses. */
254 /* We don't need an in-charge parameter for constructors that don't
255 have virtual bases. */
266 /* If this is a subobject constructor or destructor, our caller will
267 pass us a pointer to our VTT. */
269 {
272 /* First add it to DECL_ARGUMENTS between 'this' and the real args... */
276 /* ...and then to TYPE_ARG_TYPES. */
280 }
282 /* Then add the in-charge parm (before the VTT parm). */
288 /* Insert our new parameter(s) into the list. */
291 /* And rebuild the function type. */
293 arg_types);
298 fntype = (cp_build_type_attribute_variant
302 /* Now we've got the in-charge parameter. */
304 }
306 /* Classes overload their constituent function names automatically.
307 When a function name is declared in a record structure,
308 its name is changed to it overloaded name. Since names for
309 constructors and destructors can conflict, we place a leading
310 '$' for destructors.
312 CNAME is the name of the class we are grokking for.
314 FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'.
316 FLAGS contains bits saying what's special about today's
317 arguments. DTOR_FLAG == DESTRUCTOR.
319 If FUNCTION is a destructor, then we must add the `auto-delete' field
320 as a second parameter. There is some hair associated with the fact
321 that we must "declare" this variable in the manner consistent with the
322 way the rest of the arguments were declared.
324 QUALS are the qualifiers for the this pointer. */
326 void
328 {
331 /* Even within an `extern "C"' block, members get C++ linkage. See
332 [dcl.link] for details. */
336 {
340 }
349 }
351 /* Create an ARRAY_REF, checking for the user doing things backwards
352 along the way. DECLTYPE_P is for N3276, as in the parser. */
354 tree
357 {
358 tree type;
359 tree expr;
368 {
375 }
381 /* If they have an `operator[]', use that. */
383 {
389 }
390 else
391 {
394 /* Otherwise, create an ARRAY_REF for a pointer or array type.
395 It is a little-known fact that, if `a' is an array and `i' is
396 an int, you can write `i[a]', which means the same thing as
397 `a[i]'. */
400 else
405 else
420 else
421 {
425 }
431 }
433 {
440 }
442 }
444 /* Given the cast expression EXP, checking out its validity. Either return
445 an error_mark_node if there was an unavoidable error, return a cast to
446 void for trying to delete a pointer w/ the value 0, or return the
447 call to delete. If DOING_VEC is true, we handle things differently
448 for doing an array delete.
449 Implements ARM $5.3.4. This is called from the parser. */
451 tree
453 tsubst_flags_t complain)
454 {
461 {
467 }
469 /* An array can't have been allocated by new, so complain. */
476 {
480 }
484 /* As of Valley Forge, you can delete a pointer to const. */
486 /* You can't delete functions. */
488 {
492 }
494 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */
496 {
499 }
501 /* Deleting a pointer with the value zero is valid and has no effect. */
507 sfk_deleting_destructor,
509 else
512 complain);
513 }
515 /* Report an error if the indicated template declaration is not the
516 sort of thing that should be a member template. */
518 void
520 {
521 tree decl;
530 {
531 /* The parser rejects template declarations in local classes
532 (with the exception of generic lambdas). */
534 /* The parser rejects any use of virtual in a function template. */
538 /* The debug-information generating code doesn't know what to do
539 with member templates. */
541 }
544 else
546 }
548 /* Sanity check: report error if this function FUNCTION is not
549 really a member of the class (CTYPE) it is supposed to belong to.
550 TEMPLATE_PARMS is used to specify the template parameters of a member
551 template passed as FUNCTION_DECL. If the member template is passed as a
552 TEMPLATE_DECL, it can be NULL since the parameters can be extracted
553 from the declaration. If the function is not a function template, it
554 must be NULL.
555 It returns the original declaration for the function, NULL_TREE if
556 no declaration was found, error_mark_node if an error was emitted. */
558 tree
560 {
563 tree pushed_scope;
569 /* Since this is a specialization of a member template,
570 we're not going to find the declaration in the class.
571 For example, in:
573 struct S { template <typename T> void f(T); };
574 template <> void S::f(int);
576 we're not going to find `S::f(int)', but there's no
577 reason we should, either. We let our callers know we didn't
578 find the method, but we don't complain. */
581 /* Basic sanity check: for a template function, the template parameters
582 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */
584 {
588 {
592 }
594 }
596 /* OK, is this a definition of a member template? */
599 /* [temp.mem]
601 A destructor shall not be a member template. */
603 {
606 }
608 /* We must enter the scope here, because conversion operators are
609 named by target type, and type equivalence relies on typenames
610 resolving within the scope of CTYPE. */
614 {
618 {
623 /* We cannot simply call decls_match because this doesn't
624 work for static member functions that are pretending to
625 be methods, and because the name may have been changed by
626 asm("new_name"). */
628 /* Get rid of the this parameter on functions that become
629 static. */
634 /* A member template definition only matches a member template
635 declaration. */
639 /* ref-qualifier or absence of same must match. */
644 // Include constraints in the match.
648 /* While finding a match, same types and params are not enough
649 if the function is versioned. Also check version ("target")
650 attributes. */
655 && (!is_template
664 {
668 }
669 }
682 do
683 {
688 {
690 {
695 }
697 }
698 }
701 {
705 }
706 }
709 else
716 }
718 /* DECL is a function with vague linkage. Remember it so that at the
719 end of the translation unit we can decide whether or not to emit
720 it. */
722 void
724 {
727 }
729 /* As above, but for variable template instantiations. */
731 void
733 {
735 }
737 /* We have just processed the DECL, which is a static data member.
738 The other parameters are as for cp_finish_decl. */
740 void
743 tree asmspec_tree,
745 {
748 /* We cannot call pushdecl here, because that would fill in the
749 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do
750 the right thing, namely, to put this decl out straight away. */
756 /* We already complained about the template definition. */
760 else
764 {
770 }
779 }
781 /* DECLARATOR and DECLSPECS correspond to a class member. The other
782 parameters are as for cp_finish_decl. Return the DECL for the
783 class member declared. */
785 tree
789 tree asmspec_tree,
790 tree attrlist)
791 {
792 tree value;
795 tree name;
805 /* friend or constructor went bad. */
811 {
814 }
816 /* Pass friendly classes back. */
824 {
826 {
829 }
834 value);
835 }
837 /* Stash away type declarations. */
839 {
844 {
847 /* If this is a typedef that names the class for linkage purposes
848 (7.1.3p8), apply any attributes directly to the type. */
854 }
861 /* It's important that push_template_decl below follows
862 set_underlying_type above so that the created template
863 carries the properly set type of VALUE. */
869 }
874 {
877 }
883 {
885 {
887 {
891 }
893 {
895 {
899 }
900 }
904 {
909 else
911 value);
912 }
913 else
914 {
918 value);
919 else
921 value);
922 }
923 }
928 }
930 /* Pass friend decls back. */
936 /* Need to set this before push_template_decl. */
941 {
945 }
952 else
956 {
981 /* Pass friends back this way. */
990 }
992 }
994 /* Like `grokfield', but for bitfields.
995 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */
997 tree
1000 tree attrlist)
1001 {
1009 /* Pass friendly classes back. */
1016 {
1019 }
1022 {
1025 }
1027 /* Usually, finish_struct_1 catches bitfields with invalid types.
1028 But, in the case of bitfields with function type, we confuse
1029 ourselves into thinking they are member functions, so we must
1030 check here. */
1032 {
1036 }
1039 {
1043 }
1046 {
1049 }
1053 {
1054 /* The width must be an integer type. */
1059 else
1060 {
1063 }
1064 }
1072 }
1074 \f
1075 /* Returns true iff ATTR is an attribute which needs to be applied at
1076 instantiation time rather than template definition time. */
1078 static bool
1080 {
1084 tree arg;
1087 /* Unknown attribute. */
1090 /* Attribute weak handling wants to write out assembly right away. */
1094 /* Attributes used and unused are applied directly, as they appertain to
1095 decls. */
1100 /* Attribute tls_model wants to modify the symtab. */
1104 /* #pragma omp declare simd attribute needs to be always deferred. */
1109 /* An attribute pack is clearly dependent. */
1113 /* If any of the arguments are dependent expressions, we can't evaluate
1114 the attribute until instantiation time. */
1116 {
1119 /* If the first attribute argument is an identifier, only consider
1120 second and following arguments. Attributes like mode, format,
1121 cleanup and several target specific attributes aren't late
1122 just because they have an IDENTIFIER_NODE as first argument. */
1130 }
1135 {
1138 /* We can't apply any attributes to a completely unknown type until
1139 instantiation time. */
1145 /* Also defer most attributes on dependent types. This is not
1146 necessary in all cases, but is the better default. */
1148 /* But some attributes specifically apply to templates. */
1153 else
1155 }
1156 else
1158 }
1160 /* ATTR_P is a list of attributes. Remove any attributes which need to be
1161 applied at instantiation time and return them. If IS_DEPENDENT is true,
1162 the declaration itself is dependent, so all attributes should be applied
1163 at instantiation time. */
1165 static tree
1167 {
1176 {
1178 {
1184 }
1185 else
1187 }
1190 }
1192 /* Remove any late attributes from the list in ATTR_P and attach them to
1193 DECL_P. */
1195 static void
1197 {
1209 else
1214 /* Merge the late attributes at the beginning with the attribute
1215 list. */
1220 {
1221 /* We've added new attributes directly to the main variant, so
1222 now we need to update all of the other variants to include
1223 these new attributes. */
1224 tree variant;
1227 {
1230 }
1231 }
1232 }
1234 /* True if ATTRS contains any dependent attributes that affect type
1235 identity. */
1237 bool
1239 {
1242 {
1246 }
1248 }
1250 /* Return true iff ATTRS are acceptable attributes to be applied in-place
1251 to a typedef which gives a previously unnamed class or enum a name for
1252 linkage purposes. */
1254 bool
1256 {
1258 {
1262 }
1264 }
1266 /* Like reconstruct_complex_type, but handle also template trees. */
1268 tree
1270 {
1275 {
1279 }
1281 {
1285 }
1287 {
1290 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the
1291 element type qualification will be handled by the recursive
1292 cp_reconstruct_complex_type call and cp_build_qualified_type
1293 for ARRAY_TYPEs changes the element type. */
1295 }
1297 {
1304 }
1306 {
1309 /* The build_method_type_directly() routine prepends 'this' to argument list,
1310 so we must compensate by getting rid of it. */
1311 outer
1312 = build_method_type_directly
1315 }
1317 {
1320 }
1321 else
1332 }
1334 /* Replaces any constexpr expression that may be into the attributes
1335 arguments with their reduced value. */
1337 static void
1339 {
1343 tree attr;
1345 {
1346 tree arg;
1348 {
1352 }
1353 }
1354 }
1356 /* Return true if TYPE is an OpenMP mappable type. */
1357 bool
1359 {
1360 /* Mappable type has to be complete. */
1363 /* Arrays have mappable type if the elements have mappable type. */
1366 /* A mappable type cannot contain virtual members. */
1369 /* All data members must be non-static. */
1371 {
1372 tree field;
1376 /* All fields must have mappable types. */
1380 }
1382 }
1384 /* Like decl_attributes, but handle C++ complexity. */
1386 void
1388 {
1393 /* Add implicit "omp declare target" attribute if requested. */
1398 {
1408 else
1411 }
1414 {
1419 }
1427 {
1428 attributes
1432 }
1433 else
1439 /* Propagate deprecation out to the template. */
1442 {
1448 }
1449 }
1450 \f
1451 /* Walks through the namespace- or function-scope anonymous union
1452 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1453 Returns one of the fields for use in the mangled name. */
1455 static tree
1457 {
1459 tree field;
1461 /* Rather than write the code to handle the non-union case,
1462 just give an error. */
1464 {
1467 }
1472 {
1473 tree decl;
1474 tree ref;
1479 {
1481 "%q#D invalid; an anonymous union can only "
1484 }
1496 else
1501 {
1502 tree base;
1518 }
1521 else
1526 }
1529 }
1531 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1532 anonymous union, then all members must be laid out together. PUBLIC_P
1533 is nonzero if this union is not declared static. */
1535 void
1537 {
1538 tree type;
1539 tree main_decl;
1548 /* The VAR_DECL's context is the same as the TYPE's context. */
1555 {
1558 }
1564 {
1567 }
1570 {
1571 /* Use main_decl to set the mangled name. */
1577 }
1581 }
1582 \f
1583 /* Auxiliary functions to make type signatures for
1584 `operator new' and `operator delete' correspond to
1585 what compiler will be expecting. */
1587 tree
1589 {
1596 {
1599 }
1602 {
1604 {
1605 /* [basic.stc.dynamic.allocation]
1607 The first parameter shall not have an associated default
1608 argument. */
1611 /* Throw away the default argument. */
1613 }
1616 {
1619 }
1620 }
1621 else
1629 {
1632 /* Fall through. */
1634 type = build_exception_variant
1637 /* Fall through. */
1639 }
1641 }
1643 tree
1645 {
1652 {
1655 }
1659 {
1664 ptr_type_node);
1665 }
1667 {
1670 /* Fall through. */
1672 type = build_exception_variant
1675 /* Fall through. */
1677 }
1680 }
1681 \f
1682 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1683 and mark them as needed. */
1685 static void
1687 {
1688 tree fnaddr;
1691 /* It's OK for the vtable to refer to deprecated virtual functions. */
1696 {
1697 tree fn;
1703 /* This entry is an offset: a virtual base class offset, a
1704 virtual call offset, an RTTI offset, etc. */
1709 /* When we don't have vcall offsets, we output thunks whenever
1710 we output the vtables that contain them. With vcall offsets,
1711 we know all the thunks we'll need when we emit a virtual
1712 function, so we emit the thunks there instead. */
1716 }
1717 }
1719 /* Set DECL up to have the closest approximation of "initialized common"
1720 linkage available. */
1722 void
1724 {
1729 /* We can just emit function and compiler-generated variables
1730 statically; having multiple copies is (for the most part) only
1731 a waste of space.
1733 There are two correctness issues, however: the address of a
1734 template instantiation with external linkage should be the
1735 same, independent of what translation unit asks for the
1736 address, and this will not hold when we emit multiple copies of
1737 the function. However, there's little else we can do.
1739 Also, by default, the typeinfo implementation assumes that
1740 there will be only one copy of the string used as the name for
1741 each type. Therefore, if weak symbols are unavailable, the
1742 run-time library should perform a more conservative check; it
1743 should perform a string comparison, rather than an address
1744 comparison. */
1746 else
1747 {
1748 /* Static data member template instantiations, however, cannot
1749 have multiple copies. */
1754 {
1757 }
1759 {
1760 /* We can't do anything useful; leave vars for explicit
1761 instantiation. */
1764 }
1765 }
1769 }
1771 /* For win32 we also want to put explicit instantiations in
1772 linkonce sections, so that they will be merged with implicit
1773 instantiations; otherwise we get duplicate symbol errors.
1774 For Darwin we do not want explicit instantiations to be
1775 linkonce. */
1777 void
1779 {
1780 /* We used to say that this was not necessary on targets that support weak
1781 symbols, because the implicit instantiations will defer to the explicit
1782 one. However, that's not actually the case in SVR4; a strong definition
1783 after a weak one is an error. Also, not making explicit
1784 instantiations one_only means that we can end up with two copies of
1785 some template instantiations. */
1789 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1790 we can get away with not emitting them if they aren't used. We need
1791 to for variables so that cp_finish_decl will update their linkage,
1792 because their DECL_INITIAL may not have been set properly yet. */
1797 {
1801 {
1804 /* Mark it needed so we don't forget to emit it. */
1807 }
1808 }
1809 }
1811 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1812 This predicate will give the right answer during parsing of the
1813 function, which other tests may not. */
1815 bool
1817 {
1819 {
1820 /* maybe_thunk_body clears TREE_PUBLIC on the maybe-in-charge 'tor
1821 variants, check one of the "clones" for the real linkage. */
1830 }
1831 /* Unfortunately, import_export_decl has not always been called
1832 before the function is processed, so we cannot simply check
1833 DECL_COMDAT. */
1842 /* A local static in an inline effectively has vague linkage. */
1845 else
1847 }
1849 /* Determine whether or not we want to specifically import or export CTYPE,
1850 using various heuristics. */
1852 static void
1854 {
1855 /* -1 for imported, 1 for exported. */
1858 /* It only makes sense to call this function at EOF. The reason is
1859 that this function looks at whether or not the first non-inline
1860 non-abstract virtual member function has been defined in this
1861 translation unit. But, we can't possibly know that until we've
1862 seen the entire translation unit. */
1868 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1869 we will have CLASSTYPE_INTERFACE_ONLY set but not
1870 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1871 heuristic because someone will supply a #pragma implementation
1872 elsewhere, and deducing it here would produce a conflict. */
1882 /* For a template class, without -fimplicit-templates, check the
1883 repository. If the virtual table is assigned to this
1884 translation unit, then export the class; otherwise, import
1885 it. */
1888 {
1889 /* The ABI specifies that the virtual table and associated
1890 information are emitted with the key method, if any. */
1892 /* If weak symbol support is not available, then we must be
1893 careful not to emit the vtable when the key function is
1894 inline. An inline function can be defined in multiple
1895 translation units. If we were to emit the vtable in each
1896 translation unit containing a definition, we would get
1897 multiple definition errors at link-time. */
1900 }
1902 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1903 a definition anywhere else. */
1907 /* Allow back ends the chance to overrule the decision. */
1912 {
1915 }
1916 }
1918 /* Return true if VAR has already been provided to the back end; in that
1919 case VAR should not be modified further by the front end. */
1920 static bool
1922 {
1924 }
1926 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1927 must be emitted in this translation unit. Mark it as such. */
1929 void
1931 {
1934 {
1935 /* Extern inline functions don't become needed when referenced.
1936 If we know a method will be emitted in other TU and no new
1937 functions can be marked reachable, just use the external
1938 definition. */
1942 /* #pragma interface and -frepo code can call mark_needed for
1943 maybe-in-charge 'tors; mark the clones as well. */
1944 tree clone;
1947 }
1949 {
1951 /* C++ frontend use mark_decl_references to force COMDAT variables
1952 to be output that might appear dead otherwise. */
1954 }
1955 }
1957 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
1958 returns true if a definition of this entity should be provided in
1959 this object file. Callers use this function to determine whether
1960 or not to let the back end know that a definition of DECL is
1961 available in this translation unit. */
1963 bool
1965 {
1967 /* This function should only be called at the end of the translation
1968 unit. We cannot be sure of whether or not something will be
1969 COMDAT until that point. */
1972 /* All entities with external linkage that are not COMDAT/EXTERN should be
1973 emitted; they may be referred to from other object files. */
1976 /* Functions marked "dllexport" must be emitted so that they are
1977 visible to other DLLs. */
1982 /* When not optimizing, do not bother to produce definitions for extern
1983 symbols. */
1992 /* If this entity was used, let the back end see it; it will decide
1993 whether or not to emit it into the object file. */
1996 /* Virtual functions might be needed for devirtualization. */
2001 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
2002 reference to DECL might cause it to be emitted later. */
2004 }
2006 /* If necessary, write out the vtables for the dynamic class CTYPE.
2007 Returns true if any vtables were emitted. */
2009 static bool
2011 {
2012 tree vtbl;
2013 tree primary_vtbl;
2017 /* If the vtables for this class have already been emitted there is
2018 nothing more to do. */
2022 /* Ignore dummy vtables made by get_vtable_decl. */
2026 /* On some targets, we cannot determine the key method until the end
2027 of the translation unit -- which is when this function is
2028 called. */
2032 /* See if any of the vtables are needed. */
2034 {
2038 }
2040 {
2041 /* If the references to this class' vtables are optimized away,
2042 still emit the appropriate debugging information. See
2043 dfs_debug_mark. */
2048 }
2050 /* The ABI requires that we emit all of the vtables if we emit any
2051 of them. */
2053 {
2054 /* Mark entities references from the virtual table as used. */
2058 {
2061 LOOKUP_NORMAL);
2063 /* It had better be all done at compile-time. */
2065 }
2067 /* Write it out. */
2071 /* Because we're only doing syntax-checking, we'll never end up
2072 actually marking the variable as written. */
2076 {
2081 }
2082 }
2084 /* Since we're writing out the vtable here, also write the debug
2085 info. */
2089 }
2091 /* A special return value from type_visibility meaning internal
2092 linkage. */
2096 /* walk_tree helper function for type_visibility. */
2098 static tree
2100 {
2103 {
2105 }
2108 {
2111 }
2116 }
2118 /* Returns the visibility of TYPE, which is the minimum visibility of its
2119 component types. */
2121 static int
2123 {
2127 }
2129 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2130 specified (or if VISIBILITY is static). If TMPL is true, this
2131 constraint is for a template argument, and takes precedence
2132 over explicitly-specified visibility on the template. */
2134 static void
2136 {
2138 {
2139 /* extern "C" declarations aren't affected by the anonymous
2140 namespace. */
2142 {
2148 {
2153 }
2157 }
2158 }
2161 {
2163 /* This visibility was not specified. */
2165 }
2166 }
2168 /* Constrain the visibility of DECL based on the visibility of its template
2169 arguments. */
2171 static void
2173 {
2174 /* If this is a template instantiation, check the innermost
2175 template args for visibility constraints. The outer template
2176 args are covered by the class check. */
2180 {
2186 else
2187 {
2195 {
2198 else
2200 }
2201 }
2204 }
2205 }
2207 /* Like c_determine_visibility, but with additional C++-specific
2208 behavior.
2210 Function-scope entities can rely on the function's visibility because
2211 it is set in start_preparsed_function.
2213 Class-scope entities cannot rely on the class's visibility until the end
2214 of the enclosing class definition.
2216 Note that because namespaces have multiple independent definitions,
2217 namespace visibility is handled elsewhere using the #pragma visibility
2218 machinery rather than by decorating the namespace declaration.
2220 The goal is for constraints from the type to give a diagnostic, and
2221 other constraints to be applied silently. */
2223 void
2225 {
2226 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2228 /* Only relevant for names with external linkage. */
2232 /* Cloned constructors and destructors get the same visibility as
2233 the underlying function. That should be set up in
2234 maybe_clone_body. */
2240 /* The decl may be a template instantiation, which could influence
2241 visibilty. */
2244 {
2246 {
2249 }
2252 }
2256 /* If DECL is a member of a class, visibility specifiers on the
2257 class can influence the visibility of the DECL. */
2261 else
2262 {
2263 /* Not a class member. */
2265 /* Virtual tables have DECL_CONTEXT set to their associated class,
2266 so they are automatically handled above. */
2271 {
2272 /* Local statics and classes get the visibility of their
2273 containing function by default, except that
2274 -fvisibility-inlines-hidden doesn't affect them. */
2277 {
2281 }
2282 else
2283 {
2287 {
2291 }
2292 else
2293 {
2297 }
2298 }
2300 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2301 but have no TEMPLATE_INFO. Their containing template
2302 function does, and the local class could be constrained
2303 by that. */
2306 }
2309 {
2310 /* Under -fvisibility-ms-compat, types are visible by default,
2311 even though their contents aren't. */
2318 else
2320 }
2322 {
2323 /* tinfo visibility is based on the type it's for. */
2324 constrain_visibility
2327 /* Give the target a chance to override the visibility associated
2328 with DECL. */
2334 }
2336 /* Template instantiations and specializations get visibility based
2339 {
2342 else
2343 {
2344 /* Set default visibility to whatever the user supplied with
2345 #pragma GCC visibility or a namespace visibility attribute. */
2348 }
2349 }
2350 }
2353 {
2354 /* If the specialization doesn't specify visibility, use the
2355 visibility from the template. */
2363 {
2367 {
2371 else
2372 {
2376 }
2377 }
2380 /* Template argument visibility outweighs #pragma or namespace
2381 visibility, but not an explicit attribute. */
2383 {
2386 {
2387 /* A class template member with explicit visibility
2388 overrides the class visibility, so we need to apply
2389 all the levels of template args directly. */
2392 {
2395 }
2396 }
2398 /* Limit visibility based on its template arguments. */
2400 }
2401 }
2402 }
2408 /* Names in an anonymous namespace get internal linkage.
2409 This might change once we implement export. */
2412 {
2413 /* Propagate anonymity from type to decl. */
2418 }
2420 /* DR 757: A type without linkage shall not be used as the type of a
2421 variable or function with linkage, unless
2422 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2423 o the variable or function is not used (3.2 [basic.def.odr]) or is
2424 defined in the same translation unit.
2426 Since non-extern "C" decls need to be defined in the same
2427 translation unit, we can make the type internal. */
2430 /* If visibility changed and DECL already has DECL_RTL, ensure
2431 symbol flags are updated. */
2438 }
2440 /* By default, static data members and function members receive
2441 the visibility of their containing class. */
2443 static void
2445 {
2451 else
2452 {
2453 /* Default to the class visibility. */
2457 }
2459 /* Give the target a chance to override the visibility associated
2460 with DECL. */
2464 /* Construction virtual tables are not exported because
2465 they cannot be referred to from other object files;
2466 their name is not standardized by the ABI. */
2472 }
2474 /* Returns true iff DECL is an inline that should get hidden visibility
2475 because of -fvisibility-inlines-hidden. */
2477 static bool
2479 {
2481 /* Don't do this for inline templates; specializations might not be
2482 inline, and we don't want them to inherit the hidden
2483 visibility. We'll set it here for all inline instantiations. */
2484 && !processing_template_decl
2489 }
2491 /* Constrain the visibility of a class TYPE based on the visibility of its
2492 field types. Warn if any fields require lesser visibility. */
2494 void
2496 {
2497 tree binfo;
2498 tree t;
2507 /* Don't warn about visibility if the class has explicit visibility. */
2513 {
2518 {
2520 {
2523 {
2528 else
2532 }
2533 else
2537 }
2538 }
2545 }
2549 {
2553 {
2555 {
2558 {
2563 else
2567 }
2568 else
2572 }
2573 }
2579 }
2580 }
2582 /* Functions for adjusting the visibility of a tagged type and its nested
2583 types and declarations when it gets a name for linkage purposes from a
2584 typedef. */
2589 /* First reset the visibility of all the types. */
2591 static void
2593 {
2598 }
2599 static void
2601 {
2603 }
2605 /* Then reset the visibility of any static data members or member
2606 functions that use those types. */
2608 static void
2610 {
2619 }
2620 static void
2622 {
2624 {
2626 {
2631 }
2633 {
2639 }
2641 {
2645 }
2647 {
2651 {
2652 /* Also update its name, for cxx_dwarf_name. */
2656 }
2657 }
2660 }
2661 }
2662 static void
2664 {
2666 }
2667 void
2669 {
2672 }
2674 /* Set up our initial idea of what the linkage of DECL should be. */
2676 void
2678 {
2680 /* We've already made a decision as to how this function will
2683 {
2686 {
2690 /* A non-template inline function with external linkage will
2691 always be COMDAT. As we must eventually determine the
2692 linkage of all functions, and as that causes writes to
2693 the data mapped in from the PCH file, it's advantageous
2694 to mark the functions at this point. */
2698 {
2699 /* This function must have external linkage, as
2700 otherwise DECL_INTERFACE_KNOWN would have been
2701 set. */
2705 }
2706 }
2709 }
2710 }
2712 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2713 for DECL has not already been determined, do so now by setting
2714 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2715 function is called entities with vague linkage whose definitions
2716 are available must have TREE_PUBLIC set.
2718 If this function decides to place DECL in COMDAT, it will set
2719 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2720 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2721 callers defer that decision until it is clear that DECL is actually
2722 required. */
2724 void
2726 {
2735 /* We cannot determine what linkage to give to an entity with vague
2736 linkage until the end of the file. For example, a virtual table
2737 for a class will be defined if and only if the key method is
2738 defined in this translation unit. As a further example, consider
2739 that when compiling a translation unit that uses PCH file with
2740 "-frepo" it would be incorrect to make decisions about what
2741 entities to emit when building the PCH; those decisions must be
2742 delayed until the repository information has been processed. */
2744 /* Object file linkage for explicit instantiations is handled in
2745 mark_decl_instantiated. For static variables in functions with
2746 vague linkage, maybe_commonize_var is used.
2748 Therefore, the only declarations that should be provided to this
2749 function are those with external linkage that are:
2751 * implicit instantiations of function templates
2753 * inline function
2755 * implicit instantiations of static data members of class
2756 templates
2758 * virtual tables
2760 * typeinfo objects
2762 Furthermore, all entities that reach this point must have a
2763 definition available in this translation unit.
2765 The following assertions check these conditions. */
2767 /* Any code that creates entities with TREE_PUBLIC cleared should
2768 also set DECL_INTERFACE_KNOWN. */
2774 else
2778 /* Check that a definition of DECL is available in this translation
2779 unit. */
2782 /* Assume that DECL will not have COMDAT linkage. */
2784 /* Assume that DECL will not be imported into this translation
2785 unit. */
2788 /* See if the repository tells us whether or not to emit DECL in
2789 this translation unit. */
2794 {
2795 /* The repository indicates that this entity should be defined
2796 here. Make sure the back end honors that request. */
2798 /* Output the definition as an ordinary strong definition. */
2802 }
2805 /* We have already decided what to do with this DECL; there is no
2806 need to check anything further. */
2807 ;
2809 {
2819 /* The ABI requires that all virtual tables be emitted with
2820 COMDAT linkage. However, on systems where COMDAT symbols
2821 don't show up in the table of contents for a static
2822 archive, or on systems without weak symbols (where we
2823 approximate COMDAT linkage by using internal linkage), the
2824 linker will report errors about undefined symbols because
2825 it will not see the virtual table definition. Therefore,
2826 in the case that we know that the virtual table will be
2827 emitted in only one translation unit, we make the virtual
2828 table an ordinary definition with external linkage. */
2831 {
2832 /* CLASS_TYPE is being exported from this translation unit,
2833 so DECL should be defined here. */
2835 /* If a class is declared in a header with the "extern
2836 template" extension, then it will not be instantiated,
2837 even in translation units that would normally require
2838 it. Often such classes are explicitly instantiated in
2839 one translation unit. Therefore, the explicit
2840 instantiation must be made visible to other translation
2841 units. */
2843 else
2844 {
2845 /* The generic C++ ABI says that class data is always
2846 COMDAT, even if there is a key function. Some
2847 variants (e.g., the ARM EABI) says that class data
2848 only has COMDAT linkage if the class data might be
2849 emitted in more than one translation unit. When the
2850 key method can be inline and is inline, we still have
2851 to arrange for comdat even though
2852 class_data_always_comdat is false. */
2856 {
2857 /* The ABI requires COMDAT linkage. Normally, we
2858 only emit COMDAT things when they are needed;
2859 make sure that we realize that this entity is
2860 indeed needed. */
2863 }
2864 }
2865 }
2869 else
2871 }
2873 {
2876 {
2882 /* If -fno-rtti was specified, then we cannot be sure
2883 that RTTI information will be emitted with the
2884 virtual table of the class, so we must emit it
2885 wherever it is used. */
2888 else
2889 {
2892 {
2898 {
2901 }
2902 }
2903 else
2905 }
2906 }
2907 else
2909 }
2911 {
2912 /* DECL is an implicit instantiation of a function or static
2913 data member. */
2916 || (flag_implicit_inline_templates
2920 else
2921 /* If we are not implicitly generating templates, then mark
2922 this entity as undefined in this translation unit. */
2924 }
2926 {
2928 {
2932 {
2936 && ! flag_implement_inlines
2942 /* Always make artificials weak. */
2945 else
2947 }
2948 }
2949 else
2951 }
2952 else
2956 {
2957 /* If we are importing DECL into this translation unit, mark is
2958 an undefined here. */
2961 }
2963 {
2964 /* If we decided to put DECL in COMDAT, mark it accordingly at
2965 this point. */
2967 }
2970 }
2972 /* Return an expression that performs the destruction of DECL, which
2973 must be a VAR_DECL whose type has a non-trivial destructor, or is
2974 an array whose (innermost) elements have a non-trivial destructor. */
2976 tree
2978 {
2982 }
2984 /* Returns the initialization guard variable for the variable DECL,
2985 which has static storage duration. */
2987 tree
2989 {
2990 tree sname;
2991 tree guard;
2996 {
2997 tree guard_type;
2999 /* We use a type that is big enough to contain a mutex as well
3000 as an integer counter. */
3005 /* The guard should have the same linkage as what it guards. */
3023 }
3025 }
3027 /* Return an atomic load of src with the appropriate memory model. */
3029 static tree
3031 {
3046 }
3048 /* Return those bits of the GUARD variable that should be set when the
3049 guarded entity is actually initialized. */
3051 static tree
3053 {
3055 {
3056 /* We only set the first byte of the guard, in order to leave room
3057 for a mutex in the high-order bits. */
3060 guard);
3063 guard);
3065 }
3068 }
3070 /* Return an expression which determines whether or not the GUARD
3071 variable has already been initialized. */
3073 tree
3075 {
3076 tree guard_value;
3080 else
3083 /* Mask off all but the low bit. */
3085 {
3091 tf_warning_or_error);
3092 }
3099 tf_warning_or_error);
3100 }
3102 /* Return an expression which sets the GUARD variable, indicating that
3103 the variable being guarded has been initialized. */
3105 tree
3107 {
3108 tree guard_init;
3110 /* Set the GUARD to one. */
3116 tf_warning_or_error);
3117 }
3119 /* Returns true iff we can tell that VAR does not have a dynamic
3120 initializer. */
3122 static bool
3124 {
3125 /* If it's defined in another TU, we can't tell. */
3128 /* If it has a non-trivial destructor, registering the destructor
3129 counts as dynamic initialization. */
3132 /* If it's in this TU, its initializer has been processed, unless
3133 it's a case of self-initialization, then DECL_INITIALIZED_P is
3134 false while the initializer is handled by finish_id_expression. */
3137 /* If it has no initializer or a constant one, it's not dynamic. */
3140 }
3142 /* Returns true iff VAR is a variable that needs uses to be
3143 wrapped for possible dynamic initialization. */
3145 static bool
3147 {
3153 }
3155 /* Get the FUNCTION_DECL for the shared TLS init function for this
3156 translation unit. */
3158 static tree
3160 {
3164 {
3167 void_list_node));
3173 }
3175 }
3177 /* Get a FUNCTION_DECL for the init function for the thread_local
3178 variable VAR. The init function will be an alias to the function
3179 that initializes all the non-local TLS variables in the translation
3180 unit. The init function is only used by the wrapper function. */
3182 static tree
3184 {
3185 /* Only C++11 TLS vars need this init fn. */
3189 /* If -fno-extern-tls-init, assume that we don't need to call
3190 a tls init function for a variable defined in another TU. */
3194 #ifdef ASM_OUTPUT_DEF
3195 /* If the variable is internal, or if we can't generate aliases,
3196 call the local init function directly. */
3198 #endif
3204 {
3207 void_list_node));
3216 {
3218 /* If the variable is defined somewhere else and might have static
3219 initialization, make the init function a weak reference. */
3225 else
3227 }
3237 }
3239 }
3241 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3242 variable VAR. The wrapper function calls the init function (if any) for
3243 VAR and then returns a reference to VAR. The wrapper function is used
3244 in place of VAR everywhere VAR is mentioned. */
3246 tree
3248 {
3249 /* Only C++11 TLS vars need this wrapper fn. */
3256 {
3257 /* A named rvalue reference is an lvalue, so the wrapper should
3258 always return an lvalue reference. */
3267 /* The wrapper is inline and emitted everywhere var is used. */
3270 {
3272 #ifdef HAVE_GAS_HIDDEN
3273 /* Make the wrapper bind locally; there's no reason to share
3274 the wrapper between multiple shared objects. */
3277 #endif
3278 }
3284 #if 0
3285 /* We want CSE to commonize calls to the wrapper, but marking it as
3286 pure is unsafe since it has side-effects. I guess we need a new
3287 ECF flag even weaker than ECF_PURE. FIXME! */
3289 #endif
3294 }
3296 }
3298 /* At EOF, generate the definition for the TLS wrapper function FN:
3300 T& var_wrapper() {
3301 if (init_fn) init_fn();
3302 return var;
3303 } */
3305 static void
3307 {
3312 /* Only call the init fn if there might be one. */
3314 {
3316 /* If init_fn is a weakref, make sure it exists before calling. */
3318 {
3323 tf_warning_or_error);
3325 }
3329 {
3332 }
3333 }
3334 else
3335 /* If there's no initialization, the wrapper is a constant function. */
3340 }
3342 /* Start the process of running a particular set of global constructors
3343 or destructors. Subroutine of do_[cd]tors. Also called from
3344 vtv_start_verification_constructor_init_function. */
3346 static tree
3348 {
3349 tree body;
3350 tree fndecl;
3353 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3356 {
3359 #ifdef JOINER
3361 #else
3363 #endif
3366 }
3367 else
3373 NULL_TREE));
3378 /* Mark as artificial because it's not explicitly in the user's
3379 source code. */
3382 /* Mark this declaration as used to avoid spurious warnings. */
3385 /* Mark this function as a global constructor or destructor. */
3388 else
3394 }
3396 /* Finish the process of running a particular set of global constructors
3397 or destructors. Subroutine of do_[cd]tors. */
3399 static void
3401 {
3402 tree fn;
3404 /* Finish up. */
3409 {
3412 }
3413 else
3414 {
3417 }
3420 }
3422 /* The names of the parameters to the function created to handle
3423 initializations and destructions for objects with static storage
3424 duration. */
3428 /* The name of the function we create to handle initializations and
3429 destructions for objects with static storage duration. */
3432 /* The declaration for the __INITIALIZE_P argument. */
3435 /* The declaration for the __PRIORITY argument. */
3438 /* The declaration for the static storage duration function. */
3441 /* All the static storage duration functions created in this
3442 translation unit. */
3445 /* A map from priority levels to information about that priority
3446 level. There may be many such levels, so efficient lookup is
3447 important. */
3450 /* Begins the generation of the function that will handle all
3451 initialization and destruction of objects with static storage
3452 duration. The function generated takes two parameters of type
3453 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3454 nonzero, it performs initializations. Otherwise, it performs
3455 destructions. It only performs those initializations or
3456 destructions with the indicated __PRIORITY. The generated function
3457 returns no value.
3459 It is assumed that this function will only be called once per
3460 translation unit. */
3462 static tree
3464 {
3465 tree type;
3466 tree body;
3469 /* Create the identifier for this function. It will be of the form
3470 SSDF_IDENTIFIER_<number>. */
3475 NULL_TREE);
3477 /* Create the FUNCTION_DECL itself. */
3480 type);
3484 /* Put this function in the list of functions to be called from the
3485 static constructors and destructors. */
3487 {
3490 /* Take this opportunity to initialize the map from priority
3491 numbers to information about that priority level. */
3494 /*delete_value_fn=*/
3497 /* We always need to generate functions for the
3498 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3499 priorities later, we'll be sure to find the
3500 DEFAULT_INIT_PRIORITY. */
3502 }
3506 /* Create the argument list. */
3507 initialize_p_decl = cp_build_parm_decl
3510 priority_decl = cp_build_parm_decl
3517 /* Put the function in the global scope. */
3520 /* Start the function itself. This is equivalent to declaring the
3521 function as:
3523 static void __ssdf (int __initialize_p, init __priority_p);
3525 It is static because we only need to call this function from the
3526 various constructor and destructor functions for this module. */
3529 SF_PRE_PARSED);
3531 /* Set up the scope of the outermost block in the function. */
3535 }
3537 /* Finish the generation of the function which performs initialization
3538 and destruction of objects with static storage duration. After
3539 this point, no more such objects can be created. */
3541 static void
3543 {
3544 /* Close out the function. */
3547 }
3549 /* Return the information about the indicated PRIORITY level. If no
3550 code to handle this level has yet been generated, generate the
3551 appropriate prologue. */
3553 static priority_info
3555 {
3556 priority_info pi;
3557 splay_tree_node n;
3562 {
3563 /* Create a new priority information structure, and insert it
3564 into the map. */
3571 }
3572 else
3576 }
3578 /* The effective initialization priority of a DECL. */
3580 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3581 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3582 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3584 /* Whether a DECL needs a guard to protect it against multiple
3585 initialization. */
3587 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3588 || DECL_ONE_ONLY (decl) \
3589 || DECL_WEAK (decl)))
3591 /* Called from one_static_initialization_or_destruction(),
3592 via walk_tree.
3593 Walks the initializer list of a global variable and looks for
3594 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3595 and that have their DECL_CONTEXT() == NULL.
3596 For each such temporary variable, set their DECL_CONTEXT() to
3597 the current function. This is necessary because otherwise
3598 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3599 when trying to refer to a temporary variable that does not have
3600 it's DECL_CONTECT() properly set. */
3601 static tree
3605 {
3609 {
3610 tree var;
3618 }
3621 }
3623 /* Set up to handle the initialization or destruction of DECL. If
3624 INITP is nonzero, we are initializing the variable. Otherwise, we
3625 are destroying it. */
3627 static void
3629 {
3631 tree guard;
3633 /* If we are supposed to destruct and there's a trivial destructor,
3634 nothing has to be done. */
3639 /* Trick the compiler into thinking we are at the file and line
3640 where DECL was declared so that error-messages make sense, and so
3641 that the debugger will show somewhat sensible file and line
3642 information. */
3645 /* Make sure temporary variables in the initialiser all have
3646 their DECL_CONTEXT() set to a value different from NULL_TREE.
3647 This can happen when global variables initializers are built.
3648 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3649 the temporary variables that might have been generated in the
3650 accompanying initializers is NULL_TREE, meaning the variables have been
3651 declared in the global namespace.
3652 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3653 of the temporaries are set to the current function decl. */
3655 fix_temporary_vars_context_r,
3656 NULL);
3658 /* Because of:
3660 [class.access.spec]
3662 Access control for implicit calls to the constructors,
3663 the conversion functions, or the destructor called to
3664 create and destroy a static data member is performed as
3665 if these calls appeared in the scope of the member's
3666 class.
3668 we pretend we are in a static member function of the class of
3669 which the DECL is a member. */
3671 {
3674 }
3676 /* Assume we don't need a guard. */
3678 /* We need a guard if this is an object with external linkage that
3679 might be initialized in more than one place. (For example, a
3680 static data member of a template, when the data member requires
3681 construction.) */
3683 {
3684 tree guard_cond;
3688 /* When using __cxa_atexit, we just check the GUARD as we would
3689 for a local static. */
3691 {
3692 /* When using __cxa_atexit, we never try to destroy
3693 anything from a static destructor. */
3696 }
3697 /* If we don't have __cxa_atexit, then we will be running
3698 destructors from .fini sections, or their equivalents. So,
3699 we need to know how many times we've tried to initialize this
3700 object. We do initializations only if the GUARD is zero,
3701 i.e., if we are the first to initialize the variable. We do
3702 destructions only if the GUARD is one, i.e., if we are the
3703 last to destroy the variable. */
3705 guard_cond
3707 EQ_EXPR,
3709 guard,
3711 tf_warning_or_error),
3712 integer_one_node,
3713 tf_warning_or_error);
3714 else
3715 guard_cond
3717 EQ_EXPR,
3719 guard,
3721 tf_warning_or_error),
3722 integer_zero_node,
3723 tf_warning_or_error);
3727 }
3730 /* If we're using __cxa_atexit, we have not already set the GUARD,
3731 so we must do so now. */
3735 /* Perform the initialization or destruction. */
3737 {
3739 {
3742 {
3746 }
3747 }
3749 /* If we're using __cxa_atexit, register a function that calls the
3750 destructor for the object. */
3753 }
3754 else
3757 /* Finish the guard if-stmt, if necessary. */
3759 {
3762 }
3764 /* Now that we're done with DECL we don't need to pretend to be a
3765 member of its class any longer. */
3768 }
3770 /* Generate code to do the initialization or destruction of the decls in VARS,
3771 a TREE_LIST of VAR_DECL with static storage duration.
3772 Whether initialization or destruction is performed is specified by INITP. */
3774 static void
3776 {
3779 /* Build the outer if-stmt to check for initialization or destruction. */
3783 EQ_EXPR,
3784 initialize_p_decl,
3785 cond,
3786 tf_warning_or_error);
3789 /* To make sure dynamic construction doesn't access globals from other
3790 compilation units where they might not be yet constructed, for
3791 -fsanitize=address insert __asan_before_dynamic_init call that
3792 prevents access to either all global variables that need construction
3793 in other compilation units, or at least those that haven't been
3794 initialized yet. Variables that need dynamic construction in
3795 the current compilation unit are kept accessible. */
3802 tree priority_if_stmt;
3804 priority_info pi;
3806 /* If we don't need a destructor, there's nothing to do. Avoid
3807 creating a possibly empty if-stmt. */
3809 {
3812 }
3814 /* Remember that we had an initialization or finalization at this
3815 priority. */
3820 else
3823 /* Conditionalize this initialization on being in the right priority
3824 and being initializing/finalizing appropriately. */
3827 EQ_EXPR,
3828 priority_decl,
3830 tf_warning_or_error);
3833 /* Process initializers with same priority. */
3837 /* Do one initialization or destruction. */
3841 /* Finish up the priority if-stmt body. */
3847 /* Revert what __asan_before_dynamic_init did by calling
3848 __asan_after_dynamic_init. */
3852 /* Finish up the init/destruct if-stmt body. */
3855 }
3857 /* VARS is a list of variables with static storage duration which may
3858 need initialization and/or finalization. Remove those variables
3859 that don't really need to be initialized or finalized, and return
3860 the resulting list. The order in which the variables appear in
3861 VARS is in reverse order of the order in which they should actually
3862 be initialized. The list we return is in the unreversed order;
3863 i.e., the first variable should be initialized first. */
3865 static tree
3867 {
3872 {
3877 /* Deal gracefully with error. */
3879 {
3882 }
3884 /* The only things that can be initialized are variables. */
3887 /* If this object is not defined, we don't need to do anything
3888 here. */
3890 {
3893 }
3895 /* Also, if the initializer already contains errors, we can bail
3896 out now. */
3899 {
3902 }
3904 /* This variable is going to need initialization and/or
3905 finalization, so we add it to the list. */
3909 }
3912 }
3914 /* Make sure we have told the back end about all the variables in
3915 VARS. */
3917 static void
3919 {
3920 tree v;
3923 {
3926 {
3929 }
3930 }
3931 }
3933 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
3934 (otherwise) that will initialize all global objects with static
3935 storage duration having the indicated PRIORITY. */
3937 static void
3940 {
3942 tree fndecl;
3943 tree body;
3947 /* ??? */
3948 /* Was: locus->line++; */
3950 /* We use `I' to indicate initialization and `D' to indicate
3951 destruction. */
3954 /* We emit the function lazily, to avoid generating empty
3955 global constructors and destructors. */
3958 /* For Objective-C++, we may need to initialize metadata found in this module.
3959 This must be done _before_ any other static initializations. */
3962 {
3965 }
3967 /* Call the static storage duration function with appropriate
3968 arguments. */
3970 {
3971 /* Calls to pure or const functions will expand to nothing. */
3973 {
3974 tree call;
3981 constructor_p),
3983 priority),
3984 NULL_TREE);
3986 }
3987 }
3989 /* Close out the function. */
3992 }
3994 /* Generate constructor and destructor functions for the priority
3995 indicated by N. */
3997 static int
3999 {
4004 /* Generate the functions themselves, but only if they are really
4005 needed. */
4011 /* Keep iterating. */
4013 }
4015 /* Return C++ property of T, based on given operation OP. */
4017 static int
4019 {
4021 {
4023 {
4031 }
4048 }
4049 }
4051 /* Collect source file references recursively, starting from NAMESPC. */
4053 static void
4055 {
4056 /* Iterate over names in this name space. */
4059 ;
4062 else
4064 }
4066 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4067 starting from NAMESPC. */
4069 static void
4071 {
4074 /* Collect decls from this namespace. This will skip
4075 NAMESPACE_DECLs (both aliases and regular, it cannot tell). */
4078 /* Now scan for namespace children, and dump them. */
4082 }
4084 /* Returns true iff there is a definition available for variable or
4085 function DECL. */
4087 bool
4089 {
4092 /* A pending instantiation of a friend temploid is defined. */
4096 else
4097 {
4100 }
4101 }
4103 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4105 [expr.const]
4107 An integral constant-expression can only involve ... const
4108 variables of integral or enumeration types initialized with
4109 constant expressions ...
4111 C++0x also allows constexpr variables and temporaries initialized
4112 with constant expressions. We handle the former here, but the latter
4113 are just folded away in cxx_eval_constant_expression.
4115 The standard does not require that the expression be non-volatile.
4116 G++ implements the proposed correction in DR 457. */
4118 bool
4120 {
4124 /* We don't know if a template static data member is initialized with
4125 a constant expression until we instantiate its initializer. Even
4126 in the case of a constexpr variable, we can't treat it as a
4127 constant until its initializer is complete in case it's used in
4128 its own initializer. */
4131 }
4133 /* Returns true if DECL could be a symbolic constant variable, depending on
4134 its initializer. */
4136 bool
4138 {
4145 /* A proxy isn't constant. */
4152 else
4157 /* We know the initializer, and it isn't constant. */
4159 else
4161 }
4163 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4164 called from grokfndecl and grokvardecl; in all modes it is called from
4165 cp_write_global_declarations. */
4167 void
4169 {
4171 /* In C++11 it's ok if the decl is defined. */
4175 /* The type that got us on no_linkage_decls must have gotten a name for
4178 /* The type might end up having a typedef name for linkage purposes. */
4181 {
4189 /* DRs 132, 319 and 389 seem to indicate types with
4190 no linkage can only be used to declare extern "C"
4191 entities. Since it's not always an error in the
4192 ISO C++ 90 Standard, we only issue a warning. */
4194 "with no linkage used to declare variable %q#D with "
4196 else
4199 decl);
4204 }
4206 {
4209 "%q#D, declared using local type "
4211 }
4215 else
4218 }
4220 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4222 static void
4224 {
4226 }
4228 /* Clear DECL_EXTERNAL for NODE. */
4230 static bool
4232 {
4235 }
4237 /* Build up the function to run dynamic initializers for thread_local
4238 variables in this translation unit and alias the init functions for the
4239 individual variables to it. */
4241 static void
4243 {
4253 boolean_type_node);
4268 tf_warning_or_error);
4271 boolean_true_node,
4272 tf_warning_or_error));
4274 {
4279 #ifdef ASM_OUTPUT_DEF
4280 /* Output init aliases even with -fno-extern-tls-init. */
4282 {
4286 cgraph_node *alias
4290 }
4291 #endif
4292 }
4298 }
4300 /* We're at the end of compilation, so generate any mangling aliases that
4301 we've been saving up, if DECL is going to be output and ID2 isn't
4302 already taken by another declaration. */
4304 static void
4306 {
4307 /* If there's a declaration already using this mangled name,
4308 don't create a compatibility alias that conflicts. */
4315 /* Don't create an alias to an unreferenced function. */
4327 else
4329 }
4331 /* Note that we might want to emit an alias with the symbol ID2 for DECL at
4332 the end of translation, for compatibility across bugs in the mangling
4333 implementation. */
4335 void
4337 {
4338 #ifdef ASM_OUTPUT_DEF
4341 else
4342 {
4345 }
4346 #endif
4347 }
4349 /* Emit all mangling aliases that were deferred up to this point. */
4351 void
4353 {
4355 {
4359 }
4361 }
4363 /* The entire file is now complete. If requested, dump everything
4364 to a file. */
4366 static void
4368 {
4369 dump_flags_t flags;
4371 {
4374 }
4375 }
4379 /* Check the deallocation functions for CODE to see if we want to warn that
4380 only one was defined. */
4382 static void
4384 {
4390 {
4392 /* We're only interested in usual deallocation functions. */
4397 else
4399 }
4406 }
4408 /* Check the global deallocation functions to see if we want to warn about
4409 defining unsized without sized (or vice versa). */
4411 static void
4413 {
4418 }
4420 /* Earlier we left PTRMEM_CST in variable initializers alone so that we could
4421 look them up when evaluating non-type template parameters. Now we need to
4422 lower them to something the back end can understand. */
4424 static void
4426 {
4429 {
4433 }
4434 }
4436 /* This routine is called at the end of compilation.
4437 Its job is to create all the code needed to initialize and
4438 destroy the global aggregates. We do the destruction
4439 first, since that way we only need to reverse the decls once. */
4441 void
4443 {
4444 tree vars;
4449 tree decl;
4454 /* Bad parse errors. Just forget about it. */
4459 /* This is the point to write out a PCH if we're doing that.
4460 In that case we do not want to do anything else. */
4462 {
4463 /* Mangle all symbols at PCH creation time. */
4471 /* Ensure even the callers don't try to finalize the CU. */
4474 }
4481 /* Handle -fdump-ada-spec[-slim] */
4483 {
4486 else
4490 }
4492 /* FIXME - huh? was input_line -= 1;*/
4494 /* We now have to write out all the stuff we put off writing out.
4495 These include:
4497 o Template specializations that we have not yet instantiated,
4498 but which are needed.
4499 o Initialization and destruction for non-local objects with
4500 static storage duration. (Local objects with static storage
4501 duration are initialized when their scope is first entered,
4502 and are cleaned up via atexit.)
4503 o Virtual function tables.
4505 All of these may cause others to be needed. For example,
4506 instantiating one function may cause another to be needed, and
4507 generating the initializer for an object may cause templates to be
4508 instantiated, etc., etc. */
4512 do
4513 {
4514 tree t;
4515 tree decl;
4519 /* If there are templates that we've put off instantiating, do
4520 them now. */
4524 /* Write out virtual tables as required. Writing out the
4525 virtual table for a template class may cause the
4526 instantiation of members of that class. If we write out
4527 vtables then we remove the class from our list so we don't
4528 have to look at it again. */
4532 {
4535 }
4537 /* Write out needed type info variables. We have to be careful
4538 looping through unemitted decls, because emit_tinfo_decl may
4539 cause other variables to be needed. New elements will be
4540 appended, and we remove from the vector those that actually
4541 get emitted. */
4545 {
4548 }
4550 /* The list of objects with static storage duration is built up
4551 in reverse order. We clear STATIC_AGGREGATES so that any new
4552 aggregates added during the initialization of these will be
4553 initialized in the correct order when we next come around the
4554 loop. */
4558 {
4559 /* We need to start a new initialization function each time
4560 through the loop. That's because we need to know which
4561 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4562 isn't computed until a function is finished, and written
4563 out. That's a deficiency in the back end. When this is
4564 fixed, these initialization functions could all become
4565 inline, with resulting performance improvements. */
4566 tree ssdf_body;
4568 /* Set the line and file, so that it is obviously not from
4569 the source file. */
4573 /* Make sure the back end knows about all the variables. */
4576 /* First generate code to do all the initializations. */
4580 /* Then, generate code to do all the destructions. Do these
4581 in reverse order so that the most recently constructed
4582 variable is the first destroyed. If we're using
4583 __cxa_atexit, then we don't need to do this; functions
4584 were registered at initialization time to destroy the
4585 local statics. */
4587 {
4590 }
4591 else
4594 /* Finish up the static storage duration function for this
4595 round. */
4599 /* All those initializations and finalizations might cause
4600 us to need more inline functions, more template
4601 instantiations, etc. */
4603 ssdf_count++;
4604 /* ??? was: locus_at_end_of_parsing.line++; */
4605 }
4607 /* Now do the same for thread_local variables. */
4610 /* Go through the set of inline functions whose bodies have not
4611 been emitted yet. If out-of-line copies of these functions
4612 are required, emit them. */
4614 {
4615 /* Does it need synthesizing? */
4618 {
4619 /* Even though we're already at the top-level, we push
4620 there again. That way, when we pop back a few lines
4621 hence, all of our state is restored. Otherwise,
4622 finish_function doesn't clean things up, and we end
4623 up with CURRENT_FUNCTION_DECL set. */
4625 /* The decl's location will mark where it was first
4626 needed. Save that so synthesize method can indicate
4627 where it was needed from, in case of error */
4632 }
4642 /* We lie to the back end, pretending that some functions
4643 are not defined when they really are. This keeps these
4644 functions from being put out unnecessarily. But, we must
4645 stop lying when the functions are referenced, or if they
4646 are not comdat since they need to be put out now. If
4647 DECL_INTERFACE_KNOWN, then we have already set
4648 DECL_EXTERNAL appropriately, so there's no need to check
4649 again, and we do not want to clear DECL_EXTERNAL if a
4650 previous call to import_export_decl set it.
4652 This is done in a separate for cycle, because if some
4653 deferred function is contained in another deferred
4654 function later in deferred_fns varray,
4655 rest_of_compilation would skip this function and we
4656 really cannot expand the same function twice. */
4661 {
4667 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4668 group, we need to mark all symbols in the same comdat group
4669 that way. */
4677 }
4679 /* If we're going to need to write this function out, and
4680 there's already a body for it, create RTL for it now.
4681 (There might be no body if this is a method we haven't
4682 gotten around to synthesizing yet.) */
4687 {
4688 /* We will output the function; no longer consider it in this
4689 loop. */
4691 /* Generate RTL for this function now that we know we
4692 need it. */
4694 /* If we're compiling -fsyntax-only pretend that this
4695 function has been written out so that we don't try to
4696 expand it again. */
4700 }
4701 }
4706 /* Static data members are just like namespace-scope globals. */
4708 {
4710 /* Don't write it out if we haven't seen a definition. */
4714 /* If this static data member is needed, provide it to the
4715 back end. */
4718 }
4724 retries++;
4725 }
4732 /* All used inline functions must have a definition at this point. */
4734 {
4737 /* If the definition actually was available here, then the
4738 fact that the function was not defined merely represents
4739 that for some reason (use of a template repository,
4740 #pragma interface, etc.) we decided not to emit the
4741 definition here. */
4743 /* Don't complain if the template was defined. */
4747 {
4750 /* Avoid a duplicate warning from check_global_declaration. */
4752 }
4753 }
4755 /* So must decls that use a type with no linkage. */
4761 /* Then, do the Objective-C stuff. This is where all the
4762 Objective-C module stuff gets generated (symtab,
4763 class/protocol/selector lists etc). This must be done after C++
4764 templates, destructors etc. so that selectors used in C++
4765 templates are properly allocated. */
4769 /* We give C linkage to static constructors and destructors. */
4772 /* Generate initialization and destruction functions for all
4773 priorities for which they are required. */
4776 generate_ctor_and_dtor_functions_for_priority,
4779 /* If this is obj-c++ and we need a static init, call
4780 generate_ctor_or_dtor_function. */
4782 DEFAULT_INIT_PRIORITY,
4785 /* We're done with the splay-tree now. */
4789 /* Generate any missing aliases. */
4792 /* We're done with static constructors, so we can go back to "C++"
4793 linkage now. */
4797 {
4801 }
4809 /* The entire file is now complete. If requested, dump everything
4810 to a file. */
4814 {
4817 }
4822 /* Indicate that we're done with front end processing. */
4824 }
4826 /* Perform any post compilation-proper cleanups for the C++ front-end.
4827 This should really go away. No front-end should need to do
4828 anything past the compilation process. */
4830 void
4832 {
4836 {
4837 /* Generate the special constructor initialization function that
4838 calls __VLTRegisterPairs, and give it a very high
4839 initialization priority. This must be done after
4840 finalize_compilation_unit so that we have accurate
4841 information about which vtable will actually be emitted. */
4843 }
4851 }
4853 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
4854 function to call in parse-tree form; it has not yet been
4855 semantically analyzed. ARGS are the arguments to the function.
4856 They have already been semantically analyzed. This may change
4857 ARGS. */
4859 tree
4861 tsubst_flags_t complain)
4862 {
4863 tree orig_fn;
4865 tree expr;
4866 tree object;
4872 {
4881 /* Transform the arguments and add the implicit "this"
4882 parameter. That must be done before the FN is transformed
4883 because we depend on the form of FN. */
4887 {
4891 }
4892 /* Now that the arguments are done, transform FN. */
4894 }
4896 /* A qualified name corresponding to a bound pointer-to-member is
4897 represented as an OFFSET_REF:
4899 struct B { void g(); };
4900 void (B::*p)();
4901 void B::g() { (this->*p)(); } */
4903 {
4907 complain);
4909 }
4913 else
4922 }
4925 void
4927 {
4932 {
4936 {
4939 }
4940 }
4941 }
4943 /* Return true if function DECL can be inlined. This is used to force
4944 instantiation of methods that might be interesting for inlining. */
4945 bool
4947 {
4953 /* When optimizing, we might inline everything when flatten
4954 attribute or heuristics inlining for size or autoinlining
4955 is used. */
4957 }
4959 /* Normally, we can wait until instantiation-time to synthesize DECL.
4960 However, if DECL is a static data member initialized with a constant
4961 or a constexpr function, we need it right now because a reference to
4962 such a data member or a call to such function is not value-dependent.
4963 For a function that uses auto in the return type, we need to instantiate
4964 it to find out its type. For OpenMP user defined reductions, we need
4965 them instantiated for reduction clauses which inline them by hand
4966 directly. */
4968 static void
4970 {
4979 {
4980 /* Instantiating a function will result in garbage collection. We
4981 must treat this situation as if we were within the body of a
4982 function so as to avoid collecting live data only referenced from
4983 the stack (such as overload resolution candidates). */
4988 }
4989 }
4991 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
4992 If DECL is a specialization or implicitly declared class member,
4993 generate the actual definition. Return false if something goes
4994 wrong, true otherwise. */
4996 bool
4998 {
4999 /* If DECL is a BASELINK for a single function, then treat it just
5000 like the DECL for the function. Otherwise, if the BASELINK is
5001 for an overloaded function, we don't know which function was
5002 actually used until after overload resolution. */
5004 {
5009 }
5011 /* Set TREE_USED for the benefit of -Wunused. */
5013 /* And for structured bindings also the underlying decl. */
5023 /* Mark enumeration types as used. */
5032 {
5034 {
5037 {
5038 /* We mark a lambda conversion op as deleted if we can't
5039 generate it properly; see maybe_add_lambda_conv_op. */
5043 }
5044 }
5046 {
5050 }
5052 }
5058 /* We can only check DECL_ODR_USED on variables or functions with
5059 DECL_LANG_SPECIFIC set, and these are also the only decls that we
5060 might need special handling for. */
5064 {
5069 }
5071 /* We only want to do this processing once. We don't need to keep trying
5072 to instantiate inline templates, because unit-at-a-time will make sure
5073 we get them compiled before functions that want to inline them. */
5077 /* Normally, we can wait until instantiation-time to synthesize DECL.
5078 However, if DECL is a static data member initialized with a constant
5079 or a constexpr function, we need it right now because a reference to
5080 such a data member or a call to such function is not value-dependent.
5081 For a function that uses auto in the return type, we need to instantiate
5082 it to find out its type. For OpenMP user defined reductions, we need
5083 them instantiated for reduction clauses which inline them by hand
5084 directly. */
5090 /* Check this too in case we're within instantiate_non_dependent_expr. */
5099 {
5103 }
5105 /* If we don't need a value, then we don't need to synthesize DECL. */
5113 /* DR 757: A type without linkage shall not be used as the type of a
5114 variable or function with linkage, unless
5115 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5116 o the variable or function is not used (3.2 [basic.def.odr]) or is
5117 defined in the same translation unit. */
5124 {
5126 /* There's no way to define a local extern, and adding it to
5127 the vector interferes with GC, so give an error now. */
5129 else
5131 }
5135 /* Remember it, so we can check it was defined. */
5138 /* Is it a synthesized method that needs to be synthesized? */
5142 /* A function defaulted outside the class is synthesized either by
5143 cp_finish_decl or instantiate_decl. */
5146 {
5147 /* Defer virtual destructors so that thunks get the right
5148 linkage. */
5150 {
5153 }
5155 /* Remember the current location for a function we will end up
5156 synthesizing. Then we can inform the user where it was
5157 required in the case of error. */
5160 /* Synthesizing an implicitly defined member function will result in
5161 garbage collection. We must treat this situation as if we were
5162 within the body of a function so as to avoid collecting live data
5163 on the stack (such as overload resolution candidates).
5165 We could just let cp_write_global_declarations handle synthesizing
5166 this function by adding it to deferred_fns, but doing
5167 it at the use site produces better error messages. */
5171 /* If this is a synthesized method we don't need to
5172 do the instantiation test below. */
5173 }
5179 /* If this is a function or variable that is an instance of some
5180 template, we now know that we will need to actually do the
5181 instantiation. We check that DECL is not an explicit
5182 instantiation because that is not checked in instantiate_decl.
5184 We put off instantiating functions in order to improve compile
5185 times. Maintaining a stack of active functions is expensive,
5186 and the inliner knows to instantiate any functions it might
5187 need. Therefore, we always try to defer instantiation. */
5188 {
5193 }
5196 }
5198 bool
5200 {
5202 }
5204 tree
5206 {
5208 }
5210 tree
5212 {
5213 tree fn;
5221 }