| blob | 5d30369e80fec6fa4f14b7d984496c2875ea7ad5 |
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 {
915 {
919 }
920 else
921 {
925 }
926 }
928 {
930 {
934 }
935 }
939 {
944 else
946 value);
947 }
948 else
949 {
953 value);
954 else
956 value);
957 }
958 }
963 }
965 /* Pass friend decls back. */
971 /* Need to set this before push_template_decl. */
976 {
980 }
987 else
991 {
1016 /* Pass friends back this way. */
1025 }
1027 }
1029 /* Like `grokfield', but for bitfields.
1030 WIDTH is the width of the bitfield, a constant expression.
1031 The other parameters are as for grokfield. */
1033 tree
1036 tree attrlist)
1037 {
1046 /* Pass friendly classes back. */
1053 {
1056 }
1059 {
1062 }
1064 /* Usually, finish_struct_1 catches bitfields with invalid types.
1065 But, in the case of bitfields with function type, we confuse
1066 ourselves into thinking they are member functions, so we must
1067 check here. */
1069 {
1073 }
1076 {
1080 }
1083 {
1087 }
1090 {
1093 }
1101 {
1102 /* The width must be an integer type. */
1107 else
1108 {
1109 /* Temporarily stash the width in DECL_BIT_FIELD_REPRESENTATIVE.
1110 check_bitfield_decl picks it from there later and sets DECL_SIZE
1111 accordingly. */
1114 }
1115 }
1123 }
1125 \f
1126 /* Returns true iff ATTR is an attribute which needs to be applied at
1127 instantiation time rather than template definition time. */
1129 static bool
1131 {
1135 tree arg;
1138 /* Unknown attribute. */
1141 /* Attribute weak handling wants to write out assembly right away. */
1145 /* Attributes used and unused are applied directly, as they appertain to
1146 decls. */
1151 /* Attribute tls_model wants to modify the symtab. */
1155 /* #pragma omp declare simd attribute needs to be always deferred. */
1160 /* An attribute pack is clearly dependent. */
1164 /* If any of the arguments are dependent expressions, we can't evaluate
1165 the attribute until instantiation time. */
1167 {
1170 /* If the first attribute argument is an identifier, only consider
1171 second and following arguments. Attributes like mode, format,
1172 cleanup and several target specific attributes aren't late
1173 just because they have an IDENTIFIER_NODE as first argument. */
1181 }
1186 {
1189 /* We can't apply any attributes to a completely unknown type until
1190 instantiation time. */
1196 /* Also defer most attributes on dependent types. This is not
1197 necessary in all cases, but is the better default. */
1199 /* But some attributes specifically apply to templates. */
1204 else
1206 }
1207 else
1209 }
1211 /* ATTR_P is a list of attributes. Remove any attributes which need to be
1212 applied at instantiation time and return them. If IS_DEPENDENT is true,
1213 the declaration itself is dependent, so all attributes should be applied
1214 at instantiation time. */
1216 static tree
1218 {
1227 {
1229 {
1235 }
1236 else
1238 }
1241 }
1243 /* Remove any late attributes from the list in ATTR_P and attach them to
1244 DECL_P. */
1246 static void
1248 {
1260 else
1265 /* Merge the late attributes at the beginning with the attribute
1266 list. */
1271 {
1272 /* We've added new attributes directly to the main variant, so
1273 now we need to update all of the other variants to include
1274 these new attributes. */
1275 tree variant;
1278 {
1281 }
1282 }
1283 }
1285 /* True if ATTRS contains any dependent attributes that affect type
1286 identity. */
1288 bool
1290 {
1293 {
1297 }
1299 }
1301 /* Return true iff ATTRS are acceptable attributes to be applied in-place
1302 to a typedef which gives a previously unnamed class or enum a name for
1303 linkage purposes. */
1305 bool
1307 {
1309 {
1313 }
1315 }
1317 /* Like reconstruct_complex_type, but handle also template trees. */
1319 tree
1321 {
1326 {
1330 }
1332 {
1336 }
1338 {
1341 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the
1342 element type qualification will be handled by the recursive
1343 cp_reconstruct_complex_type call and cp_build_qualified_type
1344 for ARRAY_TYPEs changes the element type. */
1346 }
1348 {
1355 }
1357 {
1360 /* The build_method_type_directly() routine prepends 'this' to argument list,
1361 so we must compensate by getting rid of it. */
1362 outer
1363 = build_method_type_directly
1366 }
1368 {
1371 }
1372 else
1383 }
1385 /* Replaces any constexpr expression that may be into the attributes
1386 arguments with their reduced value. */
1388 static void
1390 {
1394 tree attr;
1396 {
1397 tree arg;
1399 {
1403 }
1404 }
1405 }
1407 /* Return true if TYPE is an OpenMP mappable type. */
1408 bool
1410 {
1411 /* Mappable type has to be complete. */
1414 /* Arrays have mappable type if the elements have mappable type. */
1417 /* A mappable type cannot contain virtual members. */
1420 /* All data members must be non-static. */
1422 {
1423 tree field;
1427 /* All fields must have mappable types. */
1431 }
1433 }
1435 /* Like decl_attributes, but handle C++ complexity. */
1437 void
1439 {
1444 /* Add implicit "omp declare target" attribute if requested. */
1449 {
1459 else
1462 }
1465 {
1470 }
1478 {
1479 attributes
1483 }
1484 else
1485 {
1491 {
1493 {
1496 }
1502 {
1505 }
1506 }
1509 }
1514 /* Propagate deprecation out to the template. */
1517 {
1523 }
1524 }
1525 \f
1526 /* Walks through the namespace- or function-scope anonymous union
1527 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1528 Returns one of the fields for use in the mangled name. */
1530 static tree
1532 {
1534 tree field;
1536 /* Rather than write the code to handle the non-union case,
1537 just give an error. */
1539 {
1542 }
1547 {
1548 tree decl;
1549 tree ref;
1554 {
1556 "%q#D invalid; an anonymous union can only "
1559 }
1571 else
1576 {
1577 tree base;
1593 }
1596 else
1601 }
1604 }
1606 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1607 anonymous union, then all members must be laid out together. PUBLIC_P
1608 is nonzero if this union is not declared static. */
1610 void
1612 {
1613 tree type;
1614 tree main_decl;
1623 /* The VAR_DECL's context is the same as the TYPE's context. */
1630 {
1633 }
1639 {
1642 }
1645 {
1646 /* Use main_decl to set the mangled name. */
1652 }
1656 }
1657 \f
1658 /* Auxiliary functions to make type signatures for
1659 `operator new' and `operator delete' correspond to
1660 what compiler will be expecting. */
1662 tree
1664 {
1671 {
1674 }
1677 {
1679 {
1680 /* [basic.stc.dynamic.allocation]
1682 The first parameter shall not have an associated default
1683 argument. */
1686 /* Throw away the default argument. */
1688 }
1691 {
1694 }
1695 }
1696 else
1704 {
1707 /* Fall through. */
1709 type = build_exception_variant
1712 /* Fall through. */
1714 }
1716 }
1718 tree
1720 {
1727 {
1730 }
1734 {
1739 ptr_type_node);
1740 }
1742 {
1745 /* Fall through. */
1747 type = build_exception_variant
1750 /* Fall through. */
1752 }
1755 }
1756 \f
1757 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1758 and mark them as needed. */
1760 static void
1762 {
1763 tree fnaddr;
1766 /* It's OK for the vtable to refer to deprecated virtual functions. */
1771 {
1772 tree fn;
1778 /* This entry is an offset: a virtual base class offset, a
1779 virtual call offset, an RTTI offset, etc. */
1784 /* When we don't have vcall offsets, we output thunks whenever
1785 we output the vtables that contain them. With vcall offsets,
1786 we know all the thunks we'll need when we emit a virtual
1787 function, so we emit the thunks there instead. */
1791 }
1792 }
1794 /* Set DECL up to have the closest approximation of "initialized common"
1795 linkage available. */
1797 void
1799 {
1804 /* We can just emit function and compiler-generated variables
1805 statically; having multiple copies is (for the most part) only
1806 a waste of space.
1808 There are two correctness issues, however: the address of a
1809 template instantiation with external linkage should be the
1810 same, independent of what translation unit asks for the
1811 address, and this will not hold when we emit multiple copies of
1812 the function. However, there's little else we can do.
1814 Also, by default, the typeinfo implementation assumes that
1815 there will be only one copy of the string used as the name for
1816 each type. Therefore, if weak symbols are unavailable, the
1817 run-time library should perform a more conservative check; it
1818 should perform a string comparison, rather than an address
1819 comparison. */
1821 else
1822 {
1823 /* Static data member template instantiations, however, cannot
1824 have multiple copies. */
1829 {
1832 }
1834 {
1835 /* We can't do anything useful; leave vars for explicit
1836 instantiation. */
1839 }
1840 }
1844 }
1846 /* For win32 we also want to put explicit instantiations in
1847 linkonce sections, so that they will be merged with implicit
1848 instantiations; otherwise we get duplicate symbol errors.
1849 For Darwin we do not want explicit instantiations to be
1850 linkonce. */
1852 void
1854 {
1855 /* We used to say that this was not necessary on targets that support weak
1856 symbols, because the implicit instantiations will defer to the explicit
1857 one. However, that's not actually the case in SVR4; a strong definition
1858 after a weak one is an error. Also, not making explicit
1859 instantiations one_only means that we can end up with two copies of
1860 some template instantiations. */
1864 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1865 we can get away with not emitting them if they aren't used. We need
1866 to for variables so that cp_finish_decl will update their linkage,
1867 because their DECL_INITIAL may not have been set properly yet. */
1872 {
1876 {
1879 /* Mark it needed so we don't forget to emit it. */
1882 }
1883 }
1884 }
1886 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1887 This predicate will give the right answer during parsing of the
1888 function, which other tests may not. */
1890 bool
1892 {
1894 {
1895 /* maybe_thunk_body clears TREE_PUBLIC on the maybe-in-charge 'tor
1896 variants, check one of the "clones" for the real linkage. */
1905 }
1906 /* Unfortunately, import_export_decl has not always been called
1907 before the function is processed, so we cannot simply check
1908 DECL_COMDAT. */
1917 /* A local static in an inline effectively has vague linkage. */
1920 else
1922 }
1924 /* Determine whether or not we want to specifically import or export CTYPE,
1925 using various heuristics. */
1927 static void
1929 {
1930 /* -1 for imported, 1 for exported. */
1933 /* It only makes sense to call this function at EOF. The reason is
1934 that this function looks at whether or not the first non-inline
1935 non-abstract virtual member function has been defined in this
1936 translation unit. But, we can't possibly know that until we've
1937 seen the entire translation unit. */
1943 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1944 we will have CLASSTYPE_INTERFACE_ONLY set but not
1945 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1946 heuristic because someone will supply a #pragma implementation
1947 elsewhere, and deducing it here would produce a conflict. */
1957 /* For a template class, without -fimplicit-templates, check the
1958 repository. If the virtual table is assigned to this
1959 translation unit, then export the class; otherwise, import
1960 it. */
1963 {
1964 /* The ABI specifies that the virtual table and associated
1965 information are emitted with the key method, if any. */
1967 /* If weak symbol support is not available, then we must be
1968 careful not to emit the vtable when the key function is
1969 inline. An inline function can be defined in multiple
1970 translation units. If we were to emit the vtable in each
1971 translation unit containing a definition, we would get
1972 multiple definition errors at link-time. */
1975 }
1977 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1978 a definition anywhere else. */
1982 /* Allow back ends the chance to overrule the decision. */
1987 {
1990 }
1991 }
1993 /* Return true if VAR has already been provided to the back end; in that
1994 case VAR should not be modified further by the front end. */
1995 static bool
1997 {
1999 }
2001 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
2002 must be emitted in this translation unit. Mark it as such. */
2004 void
2006 {
2009 {
2010 /* Extern inline functions don't become needed when referenced.
2011 If we know a method will be emitted in other TU and no new
2012 functions can be marked reachable, just use the external
2013 definition. */
2017 /* #pragma interface and -frepo code can call mark_needed for
2018 maybe-in-charge 'tors; mark the clones as well. */
2019 tree clone;
2022 }
2024 {
2026 /* C++ frontend use mark_decl_references to force COMDAT variables
2027 to be output that might appear dead otherwise. */
2029 }
2030 }
2032 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
2033 returns true if a definition of this entity should be provided in
2034 this object file. Callers use this function to determine whether
2035 or not to let the back end know that a definition of DECL is
2036 available in this translation unit. */
2038 bool
2040 {
2042 /* This function should only be called at the end of the translation
2043 unit. We cannot be sure of whether or not something will be
2044 COMDAT until that point. */
2047 /* All entities with external linkage that are not COMDAT/EXTERN should be
2048 emitted; they may be referred to from other object files. */
2051 /* Functions marked "dllexport" must be emitted so that they are
2052 visible to other DLLs. */
2057 /* When not optimizing, do not bother to produce definitions for extern
2058 symbols. */
2067 /* If this entity was used, let the back end see it; it will decide
2068 whether or not to emit it into the object file. */
2072 /* Virtual functions might be needed for devirtualization. */
2078 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
2079 reference to DECL might cause it to be emitted later. */
2081 }
2083 /* If necessary, write out the vtables for the dynamic class CTYPE.
2084 Returns true if any vtables were emitted. */
2086 static bool
2088 {
2089 tree vtbl;
2090 tree primary_vtbl;
2094 /* If the vtables for this class have already been emitted there is
2095 nothing more to do. */
2099 /* Ignore dummy vtables made by get_vtable_decl. */
2103 /* On some targets, we cannot determine the key method until the end
2104 of the translation unit -- which is when this function is
2105 called. */
2109 /* See if any of the vtables are needed. */
2111 {
2115 }
2117 {
2118 /* If the references to this class' vtables are optimized away,
2119 still emit the appropriate debugging information. See
2120 dfs_debug_mark. */
2125 }
2127 /* The ABI requires that we emit all of the vtables if we emit any
2128 of them. */
2130 {
2131 /* Mark entities references from the virtual table as used. */
2135 {
2138 LOOKUP_NORMAL);
2140 /* It had better be all done at compile-time. */
2142 }
2144 /* Write it out. */
2148 /* Because we're only doing syntax-checking, we'll never end up
2149 actually marking the variable as written. */
2153 {
2158 }
2159 }
2161 /* Since we're writing out the vtable here, also write the debug
2162 info. */
2166 }
2168 /* A special return value from type_visibility meaning internal
2169 linkage. */
2173 /* walk_tree helper function for type_visibility. */
2175 static tree
2177 {
2180 {
2182 }
2185 {
2188 }
2193 }
2195 /* Returns the visibility of TYPE, which is the minimum visibility of its
2196 component types. */
2198 static int
2200 {
2204 }
2206 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2207 specified (or if VISIBILITY is static). If TMPL is true, this
2208 constraint is for a template argument, and takes precedence
2209 over explicitly-specified visibility on the template. */
2211 static void
2213 {
2215 {
2216 /* extern "C" declarations aren't affected by the anonymous
2217 namespace. */
2219 {
2225 {
2230 }
2234 }
2235 }
2238 {
2240 /* This visibility was not specified. */
2242 }
2243 }
2245 /* Constrain the visibility of DECL based on the visibility of its template
2246 arguments. */
2248 static void
2250 {
2251 /* If this is a template instantiation, check the innermost
2252 template args for visibility constraints. The outer template
2253 args are covered by the class check. */
2257 {
2263 else
2264 {
2272 {
2275 else
2277 }
2278 }
2281 }
2282 }
2284 /* Like c_determine_visibility, but with additional C++-specific
2285 behavior.
2287 Function-scope entities can rely on the function's visibility because
2288 it is set in start_preparsed_function.
2290 Class-scope entities cannot rely on the class's visibility until the end
2291 of the enclosing class definition.
2293 Note that because namespaces have multiple independent definitions,
2294 namespace visibility is handled elsewhere using the #pragma visibility
2295 machinery rather than by decorating the namespace declaration.
2297 The goal is for constraints from the type to give a diagnostic, and
2298 other constraints to be applied silently. */
2300 void
2302 {
2303 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2305 /* Only relevant for names with external linkage. */
2309 /* Cloned constructors and destructors get the same visibility as
2310 the underlying function. That should be set up in
2311 maybe_clone_body. */
2317 /* The decl may be a template instantiation, which could influence
2318 visibilty. */
2321 {
2323 {
2326 }
2329 }
2333 /* If DECL is a member of a class, visibility specifiers on the
2334 class can influence the visibility of the DECL. */
2338 else
2339 {
2340 /* Not a class member. */
2342 /* Virtual tables have DECL_CONTEXT set to their associated class,
2343 so they are automatically handled above. */
2348 {
2349 /* Local statics and classes get the visibility of their
2350 containing function by default, except that
2351 -fvisibility-inlines-hidden doesn't affect them. */
2354 {
2358 }
2359 else
2360 {
2364 {
2368 }
2369 else
2370 {
2374 }
2375 }
2377 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2378 but have no TEMPLATE_INFO. Their containing template
2379 function does, and the local class could be constrained
2380 by that. */
2383 }
2386 {
2387 /* Under -fvisibility-ms-compat, types are visible by default,
2388 even though their contents aren't. */
2395 else
2397 }
2399 {
2400 /* tinfo visibility is based on the type it's for. */
2401 constrain_visibility
2404 /* Give the target a chance to override the visibility associated
2405 with DECL. */
2411 }
2413 /* Template instantiations and specializations get visibility based
2416 {
2419 else
2420 {
2421 /* Set default visibility to whatever the user supplied with
2422 #pragma GCC visibility or a namespace visibility attribute. */
2425 }
2426 }
2427 }
2430 {
2431 /* If the specialization doesn't specify visibility, use the
2432 visibility from the template. */
2440 {
2444 {
2448 else
2449 {
2453 }
2454 }
2457 /* Template argument visibility outweighs #pragma or namespace
2458 visibility, but not an explicit attribute. */
2460 {
2463 {
2464 /* A class template member with explicit visibility
2465 overrides the class visibility, so we need to apply
2466 all the levels of template args directly. */
2469 {
2472 }
2473 }
2475 /* Limit visibility based on its template arguments. */
2477 }
2478 }
2479 }
2485 /* Names in an anonymous namespace get internal linkage.
2486 This might change once we implement export. */
2489 {
2490 /* Propagate anonymity from type to decl. */
2495 }
2497 /* DR 757: A type without linkage shall not be used as the type of a
2498 variable or function with linkage, unless
2499 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2500 o the variable or function is not used (3.2 [basic.def.odr]) or is
2501 defined in the same translation unit.
2503 Since non-extern "C" decls need to be defined in the same
2504 translation unit, we can make the type internal. */
2507 /* If visibility changed and DECL already has DECL_RTL, ensure
2508 symbol flags are updated. */
2515 }
2517 /* By default, static data members and function members receive
2518 the visibility of their containing class. */
2520 static void
2522 {
2528 else
2529 {
2530 /* Default to the class visibility. */
2534 }
2536 /* Give the target a chance to override the visibility associated
2537 with DECL. */
2541 /* Construction virtual tables are not exported because
2542 they cannot be referred to from other object files;
2543 their name is not standardized by the ABI. */
2549 }
2551 /* Returns true iff DECL is an inline that should get hidden visibility
2552 because of -fvisibility-inlines-hidden. */
2554 static bool
2556 {
2558 /* Don't do this for inline templates; specializations might not be
2559 inline, and we don't want them to inherit the hidden
2560 visibility. We'll set it here for all inline instantiations. */
2561 && !processing_template_decl
2566 }
2568 /* Constrain the visibility of a class TYPE based on the visibility of its
2569 field types. Warn if any fields require lesser visibility. */
2571 void
2573 {
2574 tree binfo;
2575 tree t;
2584 /* Don't warn about visibility if the class has explicit visibility. */
2591 {
2596 {
2598 {
2601 {
2606 else
2610 }
2611 else
2615 }
2616 }
2623 }
2627 {
2631 {
2633 {
2636 {
2641 else
2645 }
2646 else
2650 }
2651 }
2657 }
2658 }
2660 /* Functions for adjusting the visibility of a tagged type and its nested
2661 types and declarations when it gets a name for linkage purposes from a
2662 typedef. */
2667 /* First reset the visibility of all the types. */
2669 static void
2671 {
2676 }
2677 static void
2679 {
2681 }
2683 /* Then reset the visibility of any static data members or member
2684 functions that use those types. */
2686 static void
2688 {
2697 }
2699 static void
2701 {
2703 {
2705 {
2710 }
2712 {
2718 }
2720 {
2724 }
2727 }
2728 }
2730 static void
2732 {
2734 }
2735 void
2737 {
2740 }
2742 /* Set up our initial idea of what the linkage of DECL should be. */
2744 void
2746 {
2748 /* We've already made a decision as to how this function will
2751 {
2754 {
2758 /* A non-template inline function with external linkage will
2759 always be COMDAT. As we must eventually determine the
2760 linkage of all functions, and as that causes writes to
2761 the data mapped in from the PCH file, it's advantageous
2762 to mark the functions at this point. */
2766 {
2767 /* This function must have external linkage, as
2768 otherwise DECL_INTERFACE_KNOWN would have been
2769 set. */
2773 }
2774 }
2777 }
2778 }
2780 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2781 for DECL has not already been determined, do so now by setting
2782 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2783 function is called entities with vague linkage whose definitions
2784 are available must have TREE_PUBLIC set.
2786 If this function decides to place DECL in COMDAT, it will set
2787 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2788 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2789 callers defer that decision until it is clear that DECL is actually
2790 required. */
2792 void
2794 {
2803 /* We cannot determine what linkage to give to an entity with vague
2804 linkage until the end of the file. For example, a virtual table
2805 for a class will be defined if and only if the key method is
2806 defined in this translation unit. As a further example, consider
2807 that when compiling a translation unit that uses PCH file with
2808 "-frepo" it would be incorrect to make decisions about what
2809 entities to emit when building the PCH; those decisions must be
2810 delayed until the repository information has been processed. */
2812 /* Object file linkage for explicit instantiations is handled in
2813 mark_decl_instantiated. For static variables in functions with
2814 vague linkage, maybe_commonize_var is used.
2816 Therefore, the only declarations that should be provided to this
2817 function are those with external linkage that are:
2819 * implicit instantiations of function templates
2821 * inline function
2823 * implicit instantiations of static data members of class
2824 templates
2826 * virtual tables
2828 * typeinfo objects
2830 Furthermore, all entities that reach this point must have a
2831 definition available in this translation unit.
2833 The following assertions check these conditions. */
2835 /* Any code that creates entities with TREE_PUBLIC cleared should
2836 also set DECL_INTERFACE_KNOWN. */
2842 else
2846 /* Check that a definition of DECL is available in this translation
2847 unit. */
2850 /* Assume that DECL will not have COMDAT linkage. */
2852 /* Assume that DECL will not be imported into this translation
2853 unit. */
2856 /* See if the repository tells us whether or not to emit DECL in
2857 this translation unit. */
2862 {
2863 /* The repository indicates that this entity should be defined
2864 here. Make sure the back end honors that request. */
2866 /* Output the definition as an ordinary strong definition. */
2870 }
2873 /* We have already decided what to do with this DECL; there is no
2874 need to check anything further. */
2875 ;
2877 {
2887 /* The ABI requires that all virtual tables be emitted with
2888 COMDAT linkage. However, on systems where COMDAT symbols
2889 don't show up in the table of contents for a static
2890 archive, or on systems without weak symbols (where we
2891 approximate COMDAT linkage by using internal linkage), the
2892 linker will report errors about undefined symbols because
2893 it will not see the virtual table definition. Therefore,
2894 in the case that we know that the virtual table will be
2895 emitted in only one translation unit, we make the virtual
2896 table an ordinary definition with external linkage. */
2899 {
2900 /* CLASS_TYPE is being exported from this translation unit,
2901 so DECL should be defined here. */
2903 /* If a class is declared in a header with the "extern
2904 template" extension, then it will not be instantiated,
2905 even in translation units that would normally require
2906 it. Often such classes are explicitly instantiated in
2907 one translation unit. Therefore, the explicit
2908 instantiation must be made visible to other translation
2909 units. */
2911 else
2912 {
2913 /* The generic C++ ABI says that class data is always
2914 COMDAT, even if there is a key function. Some
2915 variants (e.g., the ARM EABI) says that class data
2916 only has COMDAT linkage if the class data might be
2917 emitted in more than one translation unit. When the
2918 key method can be inline and is inline, we still have
2919 to arrange for comdat even though
2920 class_data_always_comdat is false. */
2924 {
2925 /* The ABI requires COMDAT linkage. Normally, we
2926 only emit COMDAT things when they are needed;
2927 make sure that we realize that this entity is
2928 indeed needed. */
2931 }
2932 }
2933 }
2937 else
2939 }
2941 {
2944 {
2950 /* If -fno-rtti was specified, then we cannot be sure
2951 that RTTI information will be emitted with the
2952 virtual table of the class, so we must emit it
2953 wherever it is used. */
2956 else
2957 {
2960 {
2966 {
2969 }
2970 }
2971 else
2973 }
2974 }
2975 else
2977 }
2979 {
2980 /* DECL is an implicit instantiation of a function or static
2981 data member. */
2984 || (flag_implicit_inline_templates
2988 else
2989 /* If we are not implicitly generating templates, then mark
2990 this entity as undefined in this translation unit. */
2992 }
2994 {
2996 {
3000 {
3004 && ! flag_implement_inlines
3010 /* Always make artificials weak. */
3013 else
3015 }
3016 }
3017 else
3019 }
3020 else
3024 {
3025 /* If we are importing DECL into this translation unit, mark is
3026 an undefined here. */
3029 }
3031 {
3032 /* If we decided to put DECL in COMDAT, mark it accordingly at
3033 this point. */
3035 }
3038 }
3040 /* Return an expression that performs the destruction of DECL, which
3041 must be a VAR_DECL whose type has a non-trivial destructor, or is
3042 an array whose (innermost) elements have a non-trivial destructor. */
3044 tree
3046 {
3050 }
3052 /* Returns the initialization guard variable for the variable DECL,
3053 which has static storage duration. */
3055 tree
3057 {
3058 tree sname;
3059 tree guard;
3064 {
3065 tree guard_type;
3067 /* We use a type that is big enough to contain a mutex as well
3068 as an integer counter. */
3073 /* The guard should have the same linkage as what it guards. */
3091 }
3093 }
3095 /* Return an atomic load of src with the appropriate memory model. */
3097 static tree
3099 {
3114 }
3116 /* Return those bits of the GUARD variable that should be set when the
3117 guarded entity is actually initialized. */
3119 static tree
3121 {
3123 {
3124 /* We only set the first byte of the guard, in order to leave room
3125 for a mutex in the high-order bits. */
3128 guard);
3131 guard);
3133 }
3136 }
3138 /* Return an expression which determines whether or not the GUARD
3139 variable has already been initialized. */
3141 tree
3143 {
3144 tree guard_value;
3148 else
3151 /* Mask off all but the low bit. */
3153 {
3159 tf_warning_or_error);
3160 }
3167 tf_warning_or_error);
3168 }
3170 /* Return an expression which sets the GUARD variable, indicating that
3171 the variable being guarded has been initialized. */
3173 tree
3175 {
3176 tree guard_init;
3178 /* Set the GUARD to one. */
3184 tf_warning_or_error);
3185 }
3187 /* Returns true iff we can tell that VAR does not have a dynamic
3188 initializer. */
3190 static bool
3192 {
3193 /* If it's defined in another TU, we can't tell. */
3196 /* If it has a non-trivial destructor, registering the destructor
3197 counts as dynamic initialization. */
3200 /* If it's in this TU, its initializer has been processed, unless
3201 it's a case of self-initialization, then DECL_INITIALIZED_P is
3202 false while the initializer is handled by finish_id_expression. */
3205 /* If it has no initializer or a constant one, it's not dynamic. */
3208 }
3210 /* Returns true iff VAR is a variable that needs uses to be
3211 wrapped for possible dynamic initialization. */
3213 static bool
3215 {
3221 }
3223 /* Get the FUNCTION_DECL for the shared TLS init function for this
3224 translation unit. */
3226 static tree
3228 {
3232 {
3235 void_list_node));
3241 }
3243 }
3245 /* Get a FUNCTION_DECL for the init function for the thread_local
3246 variable VAR. The init function will be an alias to the function
3247 that initializes all the non-local TLS variables in the translation
3248 unit. The init function is only used by the wrapper function. */
3250 static tree
3252 {
3253 /* Only C++11 TLS vars need this init fn. */
3257 /* If -fno-extern-tls-init, assume that we don't need to call
3258 a tls init function for a variable defined in another TU. */
3262 /* If the variable is internal, or if we can't generate aliases,
3263 call the local init function directly. */
3270 {
3273 void_list_node));
3282 {
3284 /* If the variable is defined somewhere else and might have static
3285 initialization, make the init function a weak reference. */
3291 else
3293 }
3303 }
3305 }
3307 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3308 variable VAR. The wrapper function calls the init function (if any) for
3309 VAR and then returns a reference to VAR. The wrapper function is used
3310 in place of VAR everywhere VAR is mentioned. */
3312 tree
3314 {
3315 /* Only C++11 TLS vars need this wrapper fn. */
3322 {
3323 /* A named rvalue reference is an lvalue, so the wrapper should
3324 always return an lvalue reference. */
3333 /* The wrapper is inline and emitted everywhere var is used. */
3336 {
3338 #ifdef HAVE_GAS_HIDDEN
3339 /* Make the wrapper bind locally; there's no reason to share
3340 the wrapper between multiple shared objects. */
3343 #endif
3344 }
3350 #if 0
3351 /* We want CSE to commonize calls to the wrapper, but marking it as
3352 pure is unsafe since it has side-effects. I guess we need a new
3353 ECF flag even weaker than ECF_PURE. FIXME! */
3355 #endif
3360 }
3362 }
3364 /* At EOF, generate the definition for the TLS wrapper function FN:
3366 T& var_wrapper() {
3367 if (init_fn) init_fn();
3368 return var;
3369 } */
3371 static void
3373 {
3378 /* Only call the init fn if there might be one. */
3380 {
3382 /* If init_fn is a weakref, make sure it exists before calling. */
3384 {
3389 tf_warning_or_error);
3391 }
3395 {
3398 }
3399 }
3400 else
3401 /* If there's no initialization, the wrapper is a constant function. */
3406 }
3408 /* Start the process of running a particular set of global constructors
3409 or destructors. Subroutine of do_[cd]tors. Also called from
3410 vtv_start_verification_constructor_init_function. */
3412 static tree
3414 {
3415 tree body;
3416 tree fndecl;
3419 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3422 {
3425 #ifdef JOINER
3427 #else
3429 #endif
3432 }
3433 else
3439 NULL_TREE));
3444 /* Mark as artificial because it's not explicitly in the user's
3445 source code. */
3448 /* Mark this declaration as used to avoid spurious warnings. */
3451 /* Mark this function as a global constructor or destructor. */
3454 else
3460 }
3462 /* Finish the process of running a particular set of global constructors
3463 or destructors. Subroutine of do_[cd]tors. */
3465 static void
3467 {
3468 tree fn;
3470 /* Finish up. */
3475 {
3478 }
3479 else
3480 {
3483 }
3486 }
3488 /* The names of the parameters to the function created to handle
3489 initializations and destructions for objects with static storage
3490 duration. */
3494 /* The name of the function we create to handle initializations and
3495 destructions for objects with static storage duration. */
3498 /* The declaration for the __INITIALIZE_P argument. */
3501 /* The declaration for the __PRIORITY argument. */
3504 /* The declaration for the static storage duration function. */
3507 /* All the static storage duration functions created in this
3508 translation unit. */
3511 /* A map from priority levels to information about that priority
3512 level. There may be many such levels, so efficient lookup is
3513 important. */
3516 /* Begins the generation of the function that will handle all
3517 initialization and destruction of objects with static storage
3518 duration. The function generated takes two parameters of type
3519 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3520 nonzero, it performs initializations. Otherwise, it performs
3521 destructions. It only performs those initializations or
3522 destructions with the indicated __PRIORITY. The generated function
3523 returns no value.
3525 It is assumed that this function will only be called once per
3526 translation unit. */
3528 static tree
3530 {
3531 tree type;
3532 tree body;
3535 /* Create the identifier for this function. It will be of the form
3536 SSDF_IDENTIFIER_<number>. */
3541 NULL_TREE);
3543 /* Create the FUNCTION_DECL itself. */
3546 type);
3550 /* Put this function in the list of functions to be called from the
3551 static constructors and destructors. */
3553 {
3556 /* Take this opportunity to initialize the map from priority
3557 numbers to information about that priority level. */
3560 /*delete_value_fn=*/
3563 /* We always need to generate functions for the
3564 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3565 priorities later, we'll be sure to find the
3566 DEFAULT_INIT_PRIORITY. */
3568 }
3572 /* Create the argument list. */
3573 initialize_p_decl = cp_build_parm_decl
3576 priority_decl = cp_build_parm_decl
3583 /* Put the function in the global scope. */
3586 /* Start the function itself. This is equivalent to declaring the
3587 function as:
3589 static void __ssdf (int __initialize_p, init __priority_p);
3591 It is static because we only need to call this function from the
3592 various constructor and destructor functions for this module. */
3595 SF_PRE_PARSED);
3597 /* Set up the scope of the outermost block in the function. */
3601 }
3603 /* Finish the generation of the function which performs initialization
3604 and destruction of objects with static storage duration. After
3605 this point, no more such objects can be created. */
3607 static void
3609 {
3610 /* Close out the function. */
3613 }
3615 /* Return the information about the indicated PRIORITY level. If no
3616 code to handle this level has yet been generated, generate the
3617 appropriate prologue. */
3619 static priority_info
3621 {
3622 priority_info pi;
3623 splay_tree_node n;
3628 {
3629 /* Create a new priority information structure, and insert it
3630 into the map. */
3637 }
3638 else
3642 }
3644 /* The effective initialization priority of a DECL. */
3646 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3647 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3648 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3650 /* Whether a DECL needs a guard to protect it against multiple
3651 initialization. */
3653 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3654 || DECL_ONE_ONLY (decl) \
3655 || DECL_WEAK (decl)))
3657 /* Called from one_static_initialization_or_destruction(),
3658 via walk_tree.
3659 Walks the initializer list of a global variable and looks for
3660 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3661 and that have their DECL_CONTEXT() == NULL.
3662 For each such temporary variable, set their DECL_CONTEXT() to
3663 the current function. This is necessary because otherwise
3664 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3665 when trying to refer to a temporary variable that does not have
3666 it's DECL_CONTECT() properly set. */
3667 static tree
3671 {
3675 {
3676 tree var;
3684 }
3687 }
3689 /* Set up to handle the initialization or destruction of DECL. If
3690 INITP is nonzero, we are initializing the variable. Otherwise, we
3691 are destroying it. */
3693 static void
3695 {
3697 tree guard;
3699 /* If we are supposed to destruct and there's a trivial destructor,
3700 nothing has to be done. */
3705 /* Trick the compiler into thinking we are at the file and line
3706 where DECL was declared so that error-messages make sense, and so
3707 that the debugger will show somewhat sensible file and line
3708 information. */
3711 /* Make sure temporary variables in the initialiser all have
3712 their DECL_CONTEXT() set to a value different from NULL_TREE.
3713 This can happen when global variables initializers are built.
3714 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3715 the temporary variables that might have been generated in the
3716 accompanying initializers is NULL_TREE, meaning the variables have been
3717 declared in the global namespace.
3718 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3719 of the temporaries are set to the current function decl. */
3721 fix_temporary_vars_context_r,
3722 NULL);
3724 /* Because of:
3726 [class.access.spec]
3728 Access control for implicit calls to the constructors,
3729 the conversion functions, or the destructor called to
3730 create and destroy a static data member is performed as
3731 if these calls appeared in the scope of the member's
3732 class.
3734 we pretend we are in a static member function of the class of
3735 which the DECL is a member. */
3737 {
3740 }
3742 /* Assume we don't need a guard. */
3744 /* We need a guard if this is an object with external linkage that
3745 might be initialized in more than one place. (For example, a
3746 static data member of a template, when the data member requires
3747 construction.) */
3749 {
3750 tree guard_cond;
3754 /* When using __cxa_atexit, we just check the GUARD as we would
3755 for a local static. */
3757 {
3758 /* When using __cxa_atexit, we never try to destroy
3759 anything from a static destructor. */
3762 }
3763 /* If we don't have __cxa_atexit, then we will be running
3764 destructors from .fini sections, or their equivalents. So,
3765 we need to know how many times we've tried to initialize this
3766 object. We do initializations only if the GUARD is zero,
3767 i.e., if we are the first to initialize the variable. We do
3768 destructions only if the GUARD is one, i.e., if we are the
3769 last to destroy the variable. */
3771 guard_cond
3773 EQ_EXPR,
3775 guard,
3777 tf_warning_or_error),
3778 integer_one_node,
3779 tf_warning_or_error);
3780 else
3781 guard_cond
3783 EQ_EXPR,
3785 guard,
3787 tf_warning_or_error),
3788 integer_zero_node,
3789 tf_warning_or_error);
3793 }
3796 /* If we're using __cxa_atexit, we have not already set the GUARD,
3797 so we must do so now. */
3801 /* Perform the initialization or destruction. */
3803 {
3805 {
3808 {
3812 }
3813 }
3815 /* If we're using __cxa_atexit, register a function that calls the
3816 destructor for the object. */
3819 }
3820 else
3823 /* Finish the guard if-stmt, if necessary. */
3825 {
3828 }
3830 /* Now that we're done with DECL we don't need to pretend to be a
3831 member of its class any longer. */
3834 }
3836 /* Generate code to do the initialization or destruction of the decls in VARS,
3837 a TREE_LIST of VAR_DECL with static storage duration.
3838 Whether initialization or destruction is performed is specified by INITP. */
3840 static void
3842 {
3845 /* Build the outer if-stmt to check for initialization or destruction. */
3849 EQ_EXPR,
3850 initialize_p_decl,
3851 cond,
3852 tf_warning_or_error);
3855 /* To make sure dynamic construction doesn't access globals from other
3856 compilation units where they might not be yet constructed, for
3857 -fsanitize=address insert __asan_before_dynamic_init call that
3858 prevents access to either all global variables that need construction
3859 in other compilation units, or at least those that haven't been
3860 initialized yet. Variables that need dynamic construction in
3861 the current compilation unit are kept accessible. */
3868 tree priority_if_stmt;
3870 priority_info pi;
3872 /* If we don't need a destructor, there's nothing to do. Avoid
3873 creating a possibly empty if-stmt. */
3875 {
3878 }
3880 /* Remember that we had an initialization or finalization at this
3881 priority. */
3886 else
3889 /* Conditionalize this initialization on being in the right priority
3890 and being initializing/finalizing appropriately. */
3893 EQ_EXPR,
3894 priority_decl,
3896 tf_warning_or_error);
3899 /* Process initializers with same priority. */
3903 /* Do one initialization or destruction. */
3907 /* Finish up the priority if-stmt body. */
3913 /* Revert what __asan_before_dynamic_init did by calling
3914 __asan_after_dynamic_init. */
3918 /* Finish up the init/destruct if-stmt body. */
3921 }
3923 /* VARS is a list of variables with static storage duration which may
3924 need initialization and/or finalization. Remove those variables
3925 that don't really need to be initialized or finalized, and return
3926 the resulting list. The order in which the variables appear in
3927 VARS is in reverse order of the order in which they should actually
3928 be initialized. The list we return is in the unreversed order;
3929 i.e., the first variable should be initialized first. */
3931 static tree
3933 {
3938 {
3943 /* Deal gracefully with error. */
3945 {
3948 }
3950 /* The only things that can be initialized are variables. */
3953 /* If this object is not defined, we don't need to do anything
3954 here. */
3956 {
3959 }
3961 /* Also, if the initializer already contains errors, we can bail
3962 out now. */
3965 {
3968 }
3970 /* This variable is going to need initialization and/or
3971 finalization, so we add it to the list. */
3975 }
3978 }
3980 /* Make sure we have told the back end about all the variables in
3981 VARS. */
3983 static void
3985 {
3986 tree v;
3989 {
3992 {
3995 }
3996 }
3997 }
3999 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
4000 (otherwise) that will initialize all global objects with static
4001 storage duration having the indicated PRIORITY. */
4003 static void
4006 {
4008 tree fndecl;
4009 tree body;
4013 /* ??? */
4014 /* Was: locus->line++; */
4016 /* We use `I' to indicate initialization and `D' to indicate
4017 destruction. */
4020 /* We emit the function lazily, to avoid generating empty
4021 global constructors and destructors. */
4024 /* For Objective-C++, we may need to initialize metadata found in this module.
4025 This must be done _before_ any other static initializations. */
4028 {
4031 }
4033 /* Call the static storage duration function with appropriate
4034 arguments. */
4036 {
4037 /* Calls to pure or const functions will expand to nothing. */
4039 {
4040 tree call;
4047 constructor_p),
4049 priority),
4050 NULL_TREE);
4052 }
4053 }
4055 /* Close out the function. */
4058 }
4060 /* Generate constructor and destructor functions for the priority
4061 indicated by N. */
4063 static int
4065 {
4070 /* Generate the functions themselves, but only if they are really
4071 needed. */
4077 /* Keep iterating. */
4079 }
4081 /* Return C++ property of T, based on given operation OP. */
4083 static int
4085 {
4087 {
4089 {
4097 }
4114 }
4115 }
4117 /* Collect source file references recursively, starting from NAMESPC. */
4119 static void
4121 {
4122 /* Iterate over names in this name space. */
4125 ;
4128 else
4130 }
4132 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4133 starting from NAMESPC. */
4135 static void
4137 {
4140 /* Collect decls from this namespace. This will skip
4141 NAMESPACE_DECLs (both aliases and regular, it cannot tell). */
4144 /* Now scan for namespace children, and dump them. */
4148 }
4150 /* Returns true iff there is a definition available for variable or
4151 function DECL. */
4153 bool
4155 {
4158 /* A pending instantiation of a friend temploid is defined. */
4162 else
4163 {
4166 }
4167 }
4169 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4171 [expr.const]
4173 An integral constant-expression can only involve ... const
4174 variables of integral or enumeration types initialized with
4175 constant expressions ...
4177 C++0x also allows constexpr variables and temporaries initialized
4178 with constant expressions. We handle the former here, but the latter
4179 are just folded away in cxx_eval_constant_expression.
4181 The standard does not require that the expression be non-volatile.
4182 G++ implements the proposed correction in DR 457. */
4184 bool
4186 {
4190 /* We don't know if a template static data member is initialized with
4191 a constant expression until we instantiate its initializer. Even
4192 in the case of a constexpr variable, we can't treat it as a
4193 constant until its initializer is complete in case it's used in
4194 its own initializer. */
4197 }
4199 /* Returns true if DECL could be a symbolic constant variable, depending on
4200 its initializer. */
4202 bool
4204 {
4211 /* A proxy isn't constant. */
4218 else
4223 /* We know the initializer, and it isn't constant. */
4225 else
4227 }
4229 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4230 called from grokfndecl and grokvardecl; in all modes it is called from
4231 cp_write_global_declarations. */
4233 void
4235 {
4237 /* In C++11 it's ok if the decl is defined. */
4241 /* The type that got us on no_linkage_decls must have gotten a name for
4244 /* The type might end up having a typedef name for linkage purposes. */
4247 {
4255 /* DRs 132, 319 and 389 seem to indicate types with
4256 no linkage can only be used to declare extern "C"
4257 entities. Since it's not always an error in the
4258 ISO C++ 90 Standard, we only issue a warning. */
4260 "with no linkage used to declare variable %q#D with "
4262 else
4265 decl);
4270 }
4272 {
4275 "%q#D, declared using local type "
4277 }
4281 else
4284 }
4286 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4288 static void
4290 {
4292 }
4294 /* Clear DECL_EXTERNAL for NODE. */
4296 static bool
4298 {
4301 }
4303 /* Build up the function to run dynamic initializers for thread_local
4304 variables in this translation unit and alias the init functions for the
4305 individual variables to it. */
4307 static void
4309 {
4319 boolean_type_node);
4334 tf_warning_or_error);
4337 boolean_true_node,
4338 tf_warning_or_error));
4340 {
4345 /* Output init aliases even with -fno-extern-tls-init. */
4347 {
4351 cgraph_node *alias
4355 }
4356 }
4362 }
4364 /* We're at the end of compilation, so generate any mangling aliases that
4365 we've been saving up, if DECL is going to be output and ID2 isn't
4366 already taken by another declaration. */
4368 static void
4370 {
4374 {
4377 /* Don't create an alias to an unreferenced function. */
4379 }
4381 tree *slot
4383 INSERT);
4385 /* If there's a declaration already using this mangled name,
4386 don't create a compatibility alias that conflicts. */
4401 else
4403 }
4405 /* Note that we might want to emit an alias with the symbol ID2 for DECL at
4406 the end of translation, for compatibility across bugs in the mangling
4407 implementation. */
4409 void
4411 {
4413 {
4416 else
4417 {
4420 }
4421 }
4422 }
4424 /* Emit all mangling aliases that were deferred up to this point. */
4426 void
4428 {
4430 {
4434 }
4436 }
4438 /* Record a mangling of DECL, whose DECL_ASSEMBLER_NAME has just been
4439 set. NEED_WARNING is true if we must warn about collisions. We do
4440 this to spot changes in mangling that may require compatibility
4441 aliases. */
4443 void
4445 {
4451 tree *slot
4453 INSERT);
4455 /* If this is already an alias, remove the alias, because the real
4456 decl takes precedence. */
4460 {
4463 }
4468 {
4475 "a later -fabi-version= (or =0)"
4478 }
4479 }
4481 /* The mangled name of DECL is being forcibly changed to NAME. Remove
4482 any existing knowledge of DECL's mangled name meaning DECL. */
4484 void
4486 {
4493 NO_INSERT))
4495 {
4498 /* If this is an alias, remove it from the symbol table. */
4503 }
4506 }
4508 /* The entire file is now complete. If requested, dump everything
4509 to a file. */
4511 static void
4513 {
4514 dump_flags_t flags;
4516 {
4519 }
4520 }
4524 /* Check the deallocation functions for CODE to see if we want to warn that
4525 only one was defined. */
4527 static void
4529 {
4535 {
4537 /* We're only interested in usual deallocation functions. */
4542 else
4544 }
4551 }
4553 /* Check the global deallocation functions to see if we want to warn about
4554 defining unsized without sized (or vice versa). */
4556 static void
4558 {
4563 }
4565 /* Earlier we left PTRMEM_CST in variable initializers alone so that we could
4566 look them up when evaluating non-type template parameters. Now we need to
4567 lower them to something the back end can understand. */
4569 static void
4571 {
4574 {
4578 }
4579 }
4581 /* This routine is called at the end of compilation.
4582 Its job is to create all the code needed to initialize and
4583 destroy the global aggregates. We do the destruction
4584 first, since that way we only need to reverse the decls once. */
4586 void
4588 {
4589 tree vars;
4594 tree decl;
4599 /* Bad parse errors. Just forget about it. */
4604 /* This is the point to write out a PCH if we're doing that.
4605 In that case we do not want to do anything else. */
4607 {
4608 /* Mangle all symbols at PCH creation time. */
4616 /* Ensure even the callers don't try to finalize the CU. */
4619 }
4626 /* Handle -fdump-ada-spec[-slim] */
4628 {
4631 else
4635 }
4637 /* FIXME - huh? was input_line -= 1;*/
4639 /* We now have to write out all the stuff we put off writing out.
4640 These include:
4642 o Template specializations that we have not yet instantiated,
4643 but which are needed.
4644 o Initialization and destruction for non-local objects with
4645 static storage duration. (Local objects with static storage
4646 duration are initialized when their scope is first entered,
4647 and are cleaned up via atexit.)
4648 o Virtual function tables.
4650 All of these may cause others to be needed. For example,
4651 instantiating one function may cause another to be needed, and
4652 generating the initializer for an object may cause templates to be
4653 instantiated, etc., etc. */
4657 do
4658 {
4659 tree t;
4660 tree decl;
4664 /* If there are templates that we've put off instantiating, do
4665 them now. */
4669 /* Write out virtual tables as required. Writing out the
4670 virtual table for a template class may cause the
4671 instantiation of members of that class. If we write out
4672 vtables then we remove the class from our list so we don't
4673 have to look at it again. */
4677 {
4680 }
4682 /* Write out needed type info variables. We have to be careful
4683 looping through unemitted decls, because emit_tinfo_decl may
4684 cause other variables to be needed. New elements will be
4685 appended, and we remove from the vector those that actually
4686 get emitted. */
4690 {
4693 }
4695 /* The list of objects with static storage duration is built up
4696 in reverse order. We clear STATIC_AGGREGATES so that any new
4697 aggregates added during the initialization of these will be
4698 initialized in the correct order when we next come around the
4699 loop. */
4703 {
4704 /* We need to start a new initialization function each time
4705 through the loop. That's because we need to know which
4706 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4707 isn't computed until a function is finished, and written
4708 out. That's a deficiency in the back end. When this is
4709 fixed, these initialization functions could all become
4710 inline, with resulting performance improvements. */
4711 tree ssdf_body;
4713 /* Set the line and file, so that it is obviously not from
4714 the source file. */
4718 /* Make sure the back end knows about all the variables. */
4721 /* First generate code to do all the initializations. */
4725 /* Then, generate code to do all the destructions. Do these
4726 in reverse order so that the most recently constructed
4727 variable is the first destroyed. If we're using
4728 __cxa_atexit, then we don't need to do this; functions
4729 were registered at initialization time to destroy the
4730 local statics. */
4732 {
4735 }
4736 else
4739 /* Finish up the static storage duration function for this
4740 round. */
4744 /* All those initializations and finalizations might cause
4745 us to need more inline functions, more template
4746 instantiations, etc. */
4748 ssdf_count++;
4749 /* ??? was: locus_at_end_of_parsing.line++; */
4750 }
4752 /* Now do the same for thread_local variables. */
4755 /* Go through the set of inline functions whose bodies have not
4756 been emitted yet. If out-of-line copies of these functions
4757 are required, emit them. */
4759 {
4760 /* Does it need synthesizing? */
4763 {
4764 /* Even though we're already at the top-level, we push
4765 there again. That way, when we pop back a few lines
4766 hence, all of our state is restored. Otherwise,
4767 finish_function doesn't clean things up, and we end
4768 up with CURRENT_FUNCTION_DECL set. */
4770 /* The decl's location will mark where it was first
4771 needed. Save that so synthesize method can indicate
4772 where it was needed from, in case of error */
4777 }
4787 /* We lie to the back end, pretending that some functions
4788 are not defined when they really are. This keeps these
4789 functions from being put out unnecessarily. But, we must
4790 stop lying when the functions are referenced, or if they
4791 are not comdat since they need to be put out now. If
4792 DECL_INTERFACE_KNOWN, then we have already set
4793 DECL_EXTERNAL appropriately, so there's no need to check
4794 again, and we do not want to clear DECL_EXTERNAL if a
4795 previous call to import_export_decl set it.
4797 This is done in a separate for cycle, because if some
4798 deferred function is contained in another deferred
4799 function later in deferred_fns varray,
4800 rest_of_compilation would skip this function and we
4801 really cannot expand the same function twice. */
4806 {
4812 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4813 group, we need to mark all symbols in the same comdat group
4814 that way. */
4822 }
4824 /* If we're going to need to write this function out, and
4825 there's already a body for it, create RTL for it now.
4826 (There might be no body if this is a method we haven't
4827 gotten around to synthesizing yet.) */
4832 {
4833 /* We will output the function; no longer consider it in this
4834 loop. */
4836 /* Generate RTL for this function now that we know we
4837 need it. */
4839 /* If we're compiling -fsyntax-only pretend that this
4840 function has been written out so that we don't try to
4841 expand it again. */
4845 }
4846 }
4851 /* Static data members are just like namespace-scope globals. */
4853 {
4855 /* Don't write it out if we haven't seen a definition. */
4859 /* If this static data member is needed, provide it to the
4860 back end. */
4863 }
4869 retries++;
4870 }
4877 /* All used inline functions must have a definition at this point. */
4879 {
4882 /* If the definition actually was available here, then the
4883 fact that the function was not defined merely represents
4884 that for some reason (use of a template repository,
4885 #pragma interface, etc.) we decided not to emit the
4886 definition here. */
4888 /* Don't complain if the template was defined. */
4892 {
4895 /* Avoid a duplicate warning from check_global_declaration. */
4897 }
4898 }
4900 /* So must decls that use a type with no linkage. */
4906 /* Then, do the Objective-C stuff. This is where all the
4907 Objective-C module stuff gets generated (symtab,
4908 class/protocol/selector lists etc). This must be done after C++
4909 templates, destructors etc. so that selectors used in C++
4910 templates are properly allocated. */
4914 /* We give C linkage to static constructors and destructors. */
4917 /* Generate initialization and destruction functions for all
4918 priorities for which they are required. */
4921 generate_ctor_and_dtor_functions_for_priority,
4924 /* If this is obj-c++ and we need a static init, call
4925 generate_ctor_or_dtor_function. */
4927 DEFAULT_INIT_PRIORITY,
4930 /* We're done with the splay-tree now. */
4934 /* Generate any missing aliases. */
4937 /* We're done with static constructors, so we can go back to "C++"
4938 linkage now. */
4942 {
4946 }
4953 /* The entire file is now complete. If requested, dump everything
4954 to a file. */
4958 {
4961 }
4966 /* Indicate that we're done with front end processing. */
4968 }
4970 /* Perform any post compilation-proper cleanups for the C++ front-end.
4971 This should really go away. No front-end should need to do
4972 anything past the compilation process. */
4974 void
4976 {
4980 {
4981 /* Generate the special constructor initialization function that
4982 calls __VLTRegisterPairs, and give it a very high
4983 initialization priority. This must be done after
4984 finalize_compilation_unit so that we have accurate
4985 information about which vtable will actually be emitted. */
4987 }
4995 }
4997 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
4998 function to call in parse-tree form; it has not yet been
4999 semantically analyzed. ARGS are the arguments to the function.
5000 They have already been semantically analyzed. This may change
5001 ARGS. */
5003 tree
5005 tsubst_flags_t complain)
5006 {
5007 tree orig_fn;
5009 tree expr;
5010 tree object;
5016 {
5025 /* Transform the arguments and add the implicit "this"
5026 parameter. That must be done before the FN is transformed
5027 because we depend on the form of FN. */
5031 {
5035 }
5036 /* Now that the arguments are done, transform FN. */
5038 }
5040 /* A qualified name corresponding to a bound pointer-to-member is
5041 represented as an OFFSET_REF:
5043 struct B { void g(); };
5044 void (B::*p)();
5045 void B::g() { (this->*p)(); } */
5047 {
5051 complain);
5053 }
5057 else
5066 }
5069 void
5071 {
5076 {
5080 {
5083 }
5084 }
5085 }
5087 /* Return true if function DECL can be inlined. This is used to force
5088 instantiation of methods that might be interesting for inlining. */
5089 bool
5091 {
5097 /* When optimizing, we might inline everything when flatten
5098 attribute or heuristics inlining for size or autoinlining
5099 is used. */
5101 }
5103 /* Normally, we can wait until instantiation-time to synthesize DECL.
5104 However, if DECL is a static data member initialized with a constant
5105 or a constexpr function, we need it right now because a reference to
5106 such a data member or a call to such function is not value-dependent.
5107 For a function that uses auto in the return type, we need to instantiate
5108 it to find out its type. For OpenMP user defined reductions, we need
5109 them instantiated for reduction clauses which inline them by hand
5110 directly. */
5112 static void
5114 {
5123 {
5124 /* Instantiating a function will result in garbage collection. We
5125 must treat this situation as if we were within the body of a
5126 function so as to avoid collecting live data only referenced from
5127 the stack (such as overload resolution candidates). */
5132 }
5133 }
5135 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
5136 If DECL is a specialization or implicitly declared class member,
5137 generate the actual definition. Return false if something goes
5138 wrong, true otherwise. */
5140 bool
5142 {
5143 /* If DECL is a BASELINK for a single function, then treat it just
5144 like the DECL for the function. Otherwise, if the BASELINK is
5145 for an overloaded function, we don't know which function was
5146 actually used until after overload resolution. */
5148 {
5153 }
5155 /* Set TREE_USED for the benefit of -Wunused. */
5157 /* And for structured bindings also the underlying decl. */
5167 /* Mark enumeration types as used. */
5177 {
5181 /* We mark a lambda conversion op as deleted if we can't
5182 generate it properly; see maybe_add_lambda_conv_op. */
5185 {
5189 }
5191 }
5197 /* We can only check DECL_ODR_USED on variables or functions with
5198 DECL_LANG_SPECIFIC set, and these are also the only decls that we
5199 might need special handling for. */
5203 {
5208 }
5210 /* We only want to do this processing once. We don't need to keep trying
5211 to instantiate inline templates, because unit-at-a-time will make sure
5212 we get them compiled before functions that want to inline them. */
5216 /* Normally, we can wait until instantiation-time to synthesize DECL.
5217 However, if DECL is a static data member initialized with a constant
5218 or a constexpr function, we need it right now because a reference to
5219 such a data member or a call to such function is not value-dependent.
5220 For a function that uses auto in the return type, we need to instantiate
5221 it to find out its type. For OpenMP user defined reductions, we need
5222 them instantiated for reduction clauses which inline them by hand
5223 directly. */
5229 /* Check this too in case we're within instantiate_non_dependent_expr. */
5238 {
5242 }
5244 /* If we don't need a value, then we don't need to synthesize DECL. */
5252 /* DR 757: A type without linkage shall not be used as the type of a
5253 variable or function with linkage, unless
5254 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5255 o the variable or function is not used (3.2 [basic.def.odr]) or is
5256 defined in the same translation unit. */
5263 {
5265 /* There's no way to define a local extern, and adding it to
5266 the vector interferes with GC, so give an error now. */
5268 else
5270 }
5274 /* Remember it, so we can check it was defined. */
5277 /* Is it a synthesized method that needs to be synthesized? */
5281 /* A function defaulted outside the class is synthesized either by
5282 cp_finish_decl or instantiate_decl. */
5285 {
5286 /* Defer virtual destructors so that thunks get the right
5287 linkage. */
5289 {
5292 }
5294 /* Remember the current location for a function we will end up
5295 synthesizing. Then we can inform the user where it was
5296 required in the case of error. */
5299 /* Synthesizing an implicitly defined member function will result in
5300 garbage collection. We must treat this situation as if we were
5301 within the body of a function so as to avoid collecting live data
5302 on the stack (such as overload resolution candidates).
5304 We could just let cp_write_global_declarations handle synthesizing
5305 this function by adding it to deferred_fns, but doing
5306 it at the use site produces better error messages. */
5310 /* If this is a synthesized method we don't need to
5311 do the instantiation test below. */
5312 }
5318 /* If this is a function or variable that is an instance of some
5319 template, we now know that we will need to actually do the
5320 instantiation. We check that DECL is not an explicit
5321 instantiation because that is not checked in instantiate_decl.
5323 We put off instantiating functions in order to improve compile
5324 times. Maintaining a stack of active functions is expensive,
5325 and the inliner knows to instantiate any functions it might
5326 need. Therefore, we always try to defer instantiation. */
5327 {
5332 }
5335 }
5337 bool
5339 {
5341 }
5343 tree
5345 {
5347 }
5349 tree
5351 {
5352 tree fn;
5360 }