| blob | 29d6c59f549a0292ffa94f04308f065b462d132d |
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 }
432 else
436 }
438 {
445 }
447 }
449 /* Given the cast expression EXP, checking out its validity. Either return
450 an error_mark_node if there was an unavoidable error, return a cast to
451 void for trying to delete a pointer w/ the value 0, or return the
452 call to delete. If DOING_VEC is true, we handle things differently
453 for doing an array delete.
454 Implements ARM $5.3.4. This is called from the parser. */
456 tree
458 tsubst_flags_t complain)
459 {
466 {
472 }
474 /* An array can't have been allocated by new, so complain. */
481 {
485 }
489 /* As of Valley Forge, you can delete a pointer to const. */
491 /* You can't delete functions. */
493 {
497 }
499 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */
501 {
504 }
506 /* Deleting a pointer with the value zero is valid and has no effect. */
512 sfk_deleting_destructor,
514 else
517 complain);
518 }
520 /* Report an error if the indicated template declaration is not the
521 sort of thing that should be a member template. */
523 void
525 {
526 tree decl;
535 {
536 /* The parser rejects template declarations in local classes
537 (with the exception of generic lambdas). */
539 /* The parser rejects any use of virtual in a function template. */
543 /* The debug-information generating code doesn't know what to do
544 with member templates. */
546 }
549 else
551 }
553 /* Sanity check: report error if this function FUNCTION is not
554 really a member of the class (CTYPE) it is supposed to belong to.
555 TEMPLATE_PARMS is used to specify the template parameters of a member
556 template passed as FUNCTION_DECL. If the member template is passed as a
557 TEMPLATE_DECL, it can be NULL since the parameters can be extracted
558 from the declaration. If the function is not a function template, it
559 must be NULL.
560 It returns the original declaration for the function, NULL_TREE if
561 no declaration was found, error_mark_node if an error was emitted. */
563 tree
565 {
570 /* Since this is a specialization of a member template,
571 we're not going to find the declaration in the class.
572 For example, in:
574 struct S { template <typename T> void f(T); };
575 template <> void S::f(int);
577 we're not going to find `S::f(int)', but there's no
578 reason we should, either. We let our callers know we didn't
579 find the method, but we don't complain. */
582 /* Basic sanity check: for a template function, the template parameters
583 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */
585 {
589 {
593 }
595 }
597 /* OK, is this a definition of a member template? */
600 /* [temp.mem]
602 A destructor shall not be a member template. */
604 {
607 }
609 /* We must enter the scope here, because conversion operators are
610 named by target type, and type equivalence relies on typenames
611 resolving within the scope of CTYPE. */
617 {
620 /* A member template definition only matches a member template
621 declaration. */
631 /* We cannot simply call decls_match because this doesn't work
632 for static member functions that are pretending to be
633 methods, and because the name may have been changed by
634 asm("new_name"). */
636 /* Get rid of the this parameter on functions that become
637 static. */
642 /* ref-qualifier or absence of same must match. */
647 // Include constraints in the match.
651 /* While finding a match, same types and params are not enough
652 if the function is versioned. Also check version ("target")
653 attributes. */
658 && (!is_template
667 }
670 {
673 else
674 {
685 else
690 }
692 }
698 }
700 /* DECL is a function with vague linkage. Remember it so that at the
701 end of the translation unit we can decide whether or not to emit
702 it. */
704 void
706 {
709 }
711 /* As above, but for variable template instantiations. */
713 void
715 {
717 }
719 /* We have just processed the DECL, which is a static data member.
720 The other parameters are as for cp_finish_decl. */
722 void
725 tree asmspec_tree,
727 {
730 /* We cannot call pushdecl here, because that would fill in the
731 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do
732 the right thing, namely, to put this decl out straight away. */
738 /* We already complained about the template definition. */
742 else
746 {
752 }
761 }
763 /* DECLARATOR and DECLSPECS correspond to a class member. The other
764 parameters are as for cp_finish_decl. Return the DECL for the
765 class member declared. */
767 tree
771 tree asmspec_tree,
772 tree attrlist)
773 {
774 tree value;
777 tree name;
787 /* friend or constructor went bad. */
793 {
796 }
798 /* Pass friendly classes back. */
806 {
808 {
811 }
816 value);
817 }
819 /* Stash away type declarations. */
821 {
826 {
829 /* If this is a typedef that names the class for linkage purposes
830 (7.1.3p8), apply any attributes directly to the type. */
836 }
843 /* It's important that push_template_decl below follows
844 set_underlying_type above so that the created template
845 carries the properly set type of VALUE. */
851 }
856 {
859 }
865 {
867 {
869 {
873 }
875 {
877 {
881 }
882 }
886 {
891 else
893 value);
894 }
895 else
896 {
900 value);
901 else
903 value);
904 }
905 }
910 }
912 /* Pass friend decls back. */
918 /* Need to set this before push_template_decl. */
923 {
927 }
934 else
938 {
963 /* Pass friends back this way. */
972 }
974 }
976 /* Like `grokfield', but for bitfields.
977 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */
979 tree
982 tree attrlist)
983 {
991 /* Pass friendly classes back. */
998 {
1001 }
1004 {
1007 }
1009 /* Usually, finish_struct_1 catches bitfields with invalid types.
1010 But, in the case of bitfields with function type, we confuse
1011 ourselves into thinking they are member functions, so we must
1012 check here. */
1014 {
1018 }
1021 {
1025 }
1028 {
1032 }
1035 {
1038 }
1042 {
1043 /* The width must be an integer type. */
1048 else
1049 {
1052 }
1053 }
1061 }
1063 \f
1064 /* Returns true iff ATTR is an attribute which needs to be applied at
1065 instantiation time rather than template definition time. */
1067 static bool
1069 {
1073 tree arg;
1076 /* Unknown attribute. */
1079 /* Attribute weak handling wants to write out assembly right away. */
1083 /* Attributes used and unused are applied directly, as they appertain to
1084 decls. */
1089 /* Attribute tls_model wants to modify the symtab. */
1093 /* #pragma omp declare simd attribute needs to be always deferred. */
1098 /* An attribute pack is clearly dependent. */
1102 /* If any of the arguments are dependent expressions, we can't evaluate
1103 the attribute until instantiation time. */
1105 {
1108 /* If the first attribute argument is an identifier, only consider
1109 second and following arguments. Attributes like mode, format,
1110 cleanup and several target specific attributes aren't late
1111 just because they have an IDENTIFIER_NODE as first argument. */
1119 }
1124 {
1127 /* We can't apply any attributes to a completely unknown type until
1128 instantiation time. */
1134 /* Also defer most attributes on dependent types. This is not
1135 necessary in all cases, but is the better default. */
1137 /* But some attributes specifically apply to templates. */
1142 else
1144 }
1145 else
1147 }
1149 /* ATTR_P is a list of attributes. Remove any attributes which need to be
1150 applied at instantiation time and return them. If IS_DEPENDENT is true,
1151 the declaration itself is dependent, so all attributes should be applied
1152 at instantiation time. */
1154 static tree
1156 {
1165 {
1167 {
1173 }
1174 else
1176 }
1179 }
1181 /* Remove any late attributes from the list in ATTR_P and attach them to
1182 DECL_P. */
1184 static void
1186 {
1198 else
1203 /* Merge the late attributes at the beginning with the attribute
1204 list. */
1209 {
1210 /* We've added new attributes directly to the main variant, so
1211 now we need to update all of the other variants to include
1212 these new attributes. */
1213 tree variant;
1216 {
1219 }
1220 }
1221 }
1223 /* True if ATTRS contains any dependent attributes that affect type
1224 identity. */
1226 bool
1228 {
1231 {
1235 }
1237 }
1239 /* Return true iff ATTRS are acceptable attributes to be applied in-place
1240 to a typedef which gives a previously unnamed class or enum a name for
1241 linkage purposes. */
1243 bool
1245 {
1247 {
1251 }
1253 }
1255 /* Like reconstruct_complex_type, but handle also template trees. */
1257 tree
1259 {
1264 {
1268 }
1270 {
1274 }
1276 {
1279 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the
1280 element type qualification will be handled by the recursive
1281 cp_reconstruct_complex_type call and cp_build_qualified_type
1282 for ARRAY_TYPEs changes the element type. */
1284 }
1286 {
1293 }
1295 {
1298 /* The build_method_type_directly() routine prepends 'this' to argument list,
1299 so we must compensate by getting rid of it. */
1300 outer
1301 = build_method_type_directly
1304 }
1306 {
1309 }
1310 else
1321 }
1323 /* Replaces any constexpr expression that may be into the attributes
1324 arguments with their reduced value. */
1326 static void
1328 {
1332 tree attr;
1334 {
1335 tree arg;
1337 {
1341 }
1342 }
1343 }
1345 /* Return true if TYPE is an OpenMP mappable type. */
1346 bool
1348 {
1349 /* Mappable type has to be complete. */
1352 /* Arrays have mappable type if the elements have mappable type. */
1355 /* A mappable type cannot contain virtual members. */
1358 /* All data members must be non-static. */
1360 {
1361 tree field;
1365 /* All fields must have mappable types. */
1369 }
1371 }
1373 /* Like decl_attributes, but handle C++ complexity. */
1375 void
1377 {
1382 /* Add implicit "omp declare target" attribute if requested. */
1387 {
1397 else
1400 }
1403 {
1408 }
1416 {
1417 attributes
1421 }
1422 else
1428 /* Propagate deprecation out to the template. */
1431 {
1437 }
1438 }
1439 \f
1440 /* Walks through the namespace- or function-scope anonymous union
1441 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1442 Returns one of the fields for use in the mangled name. */
1444 static tree
1446 {
1448 tree field;
1450 /* Rather than write the code to handle the non-union case,
1451 just give an error. */
1453 {
1456 }
1461 {
1462 tree decl;
1463 tree ref;
1468 {
1470 "%q#D invalid; an anonymous union can only "
1473 }
1485 else
1490 {
1491 tree base;
1507 }
1510 else
1515 }
1518 }
1520 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1521 anonymous union, then all members must be laid out together. PUBLIC_P
1522 is nonzero if this union is not declared static. */
1524 void
1526 {
1527 tree type;
1528 tree main_decl;
1537 /* The VAR_DECL's context is the same as the TYPE's context. */
1544 {
1547 }
1553 {
1556 }
1559 {
1560 /* Use main_decl to set the mangled name. */
1566 }
1570 }
1571 \f
1572 /* Auxiliary functions to make type signatures for
1573 `operator new' and `operator delete' correspond to
1574 what compiler will be expecting. */
1576 tree
1578 {
1585 {
1588 }
1591 {
1593 {
1594 /* [basic.stc.dynamic.allocation]
1596 The first parameter shall not have an associated default
1597 argument. */
1600 /* Throw away the default argument. */
1602 }
1605 {
1608 }
1609 }
1610 else
1618 {
1621 /* Fall through. */
1623 type = build_exception_variant
1626 /* Fall through. */
1628 }
1630 }
1632 tree
1634 {
1641 {
1644 }
1648 {
1653 ptr_type_node);
1654 }
1656 {
1659 /* Fall through. */
1661 type = build_exception_variant
1664 /* Fall through. */
1666 }
1669 }
1670 \f
1671 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1672 and mark them as needed. */
1674 static void
1676 {
1677 tree fnaddr;
1680 /* It's OK for the vtable to refer to deprecated virtual functions. */
1685 {
1686 tree fn;
1692 /* This entry is an offset: a virtual base class offset, a
1693 virtual call offset, an RTTI offset, etc. */
1698 /* When we don't have vcall offsets, we output thunks whenever
1699 we output the vtables that contain them. With vcall offsets,
1700 we know all the thunks we'll need when we emit a virtual
1701 function, so we emit the thunks there instead. */
1705 }
1706 }
1708 /* Set DECL up to have the closest approximation of "initialized common"
1709 linkage available. */
1711 void
1713 {
1718 /* We can just emit function and compiler-generated variables
1719 statically; having multiple copies is (for the most part) only
1720 a waste of space.
1722 There are two correctness issues, however: the address of a
1723 template instantiation with external linkage should be the
1724 same, independent of what translation unit asks for the
1725 address, and this will not hold when we emit multiple copies of
1726 the function. However, there's little else we can do.
1728 Also, by default, the typeinfo implementation assumes that
1729 there will be only one copy of the string used as the name for
1730 each type. Therefore, if weak symbols are unavailable, the
1731 run-time library should perform a more conservative check; it
1732 should perform a string comparison, rather than an address
1733 comparison. */
1735 else
1736 {
1737 /* Static data member template instantiations, however, cannot
1738 have multiple copies. */
1743 {
1746 }
1748 {
1749 /* We can't do anything useful; leave vars for explicit
1750 instantiation. */
1753 }
1754 }
1758 }
1760 /* For win32 we also want to put explicit instantiations in
1761 linkonce sections, so that they will be merged with implicit
1762 instantiations; otherwise we get duplicate symbol errors.
1763 For Darwin we do not want explicit instantiations to be
1764 linkonce. */
1766 void
1768 {
1769 /* We used to say that this was not necessary on targets that support weak
1770 symbols, because the implicit instantiations will defer to the explicit
1771 one. However, that's not actually the case in SVR4; a strong definition
1772 after a weak one is an error. Also, not making explicit
1773 instantiations one_only means that we can end up with two copies of
1774 some template instantiations. */
1778 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1779 we can get away with not emitting them if they aren't used. We need
1780 to for variables so that cp_finish_decl will update their linkage,
1781 because their DECL_INITIAL may not have been set properly yet. */
1786 {
1790 {
1793 /* Mark it needed so we don't forget to emit it. */
1796 }
1797 }
1798 }
1800 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1801 This predicate will give the right answer during parsing of the
1802 function, which other tests may not. */
1804 bool
1806 {
1808 {
1809 /* maybe_thunk_body clears TREE_PUBLIC on the maybe-in-charge 'tor
1810 variants, check one of the "clones" for the real linkage. */
1819 }
1820 /* Unfortunately, import_export_decl has not always been called
1821 before the function is processed, so we cannot simply check
1822 DECL_COMDAT. */
1831 /* A local static in an inline effectively has vague linkage. */
1834 else
1836 }
1838 /* Determine whether or not we want to specifically import or export CTYPE,
1839 using various heuristics. */
1841 static void
1843 {
1844 /* -1 for imported, 1 for exported. */
1847 /* It only makes sense to call this function at EOF. The reason is
1848 that this function looks at whether or not the first non-inline
1849 non-abstract virtual member function has been defined in this
1850 translation unit. But, we can't possibly know that until we've
1851 seen the entire translation unit. */
1857 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1858 we will have CLASSTYPE_INTERFACE_ONLY set but not
1859 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1860 heuristic because someone will supply a #pragma implementation
1861 elsewhere, and deducing it here would produce a conflict. */
1871 /* For a template class, without -fimplicit-templates, check the
1872 repository. If the virtual table is assigned to this
1873 translation unit, then export the class; otherwise, import
1874 it. */
1877 {
1878 /* The ABI specifies that the virtual table and associated
1879 information are emitted with the key method, if any. */
1881 /* If weak symbol support is not available, then we must be
1882 careful not to emit the vtable when the key function is
1883 inline. An inline function can be defined in multiple
1884 translation units. If we were to emit the vtable in each
1885 translation unit containing a definition, we would get
1886 multiple definition errors at link-time. */
1889 }
1891 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1892 a definition anywhere else. */
1896 /* Allow back ends the chance to overrule the decision. */
1901 {
1904 }
1905 }
1907 /* Return true if VAR has already been provided to the back end; in that
1908 case VAR should not be modified further by the front end. */
1909 static bool
1911 {
1913 }
1915 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1916 must be emitted in this translation unit. Mark it as such. */
1918 void
1920 {
1923 {
1924 /* Extern inline functions don't become needed when referenced.
1925 If we know a method will be emitted in other TU and no new
1926 functions can be marked reachable, just use the external
1927 definition. */
1931 /* #pragma interface and -frepo code can call mark_needed for
1932 maybe-in-charge 'tors; mark the clones as well. */
1933 tree clone;
1936 }
1938 {
1940 /* C++ frontend use mark_decl_references to force COMDAT variables
1941 to be output that might appear dead otherwise. */
1943 }
1944 }
1946 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
1947 returns true if a definition of this entity should be provided in
1948 this object file. Callers use this function to determine whether
1949 or not to let the back end know that a definition of DECL is
1950 available in this translation unit. */
1952 bool
1954 {
1956 /* This function should only be called at the end of the translation
1957 unit. We cannot be sure of whether or not something will be
1958 COMDAT until that point. */
1961 /* All entities with external linkage that are not COMDAT/EXTERN should be
1962 emitted; they may be referred to from other object files. */
1965 /* Functions marked "dllexport" must be emitted so that they are
1966 visible to other DLLs. */
1971 /* When not optimizing, do not bother to produce definitions for extern
1972 symbols. */
1981 /* If this entity was used, let the back end see it; it will decide
1982 whether or not to emit it into the object file. */
1986 /* Virtual functions might be needed for devirtualization. */
1992 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
1993 reference to DECL might cause it to be emitted later. */
1995 }
1997 /* If necessary, write out the vtables for the dynamic class CTYPE.
1998 Returns true if any vtables were emitted. */
2000 static bool
2002 {
2003 tree vtbl;
2004 tree primary_vtbl;
2008 /* If the vtables for this class have already been emitted there is
2009 nothing more to do. */
2013 /* Ignore dummy vtables made by get_vtable_decl. */
2017 /* On some targets, we cannot determine the key method until the end
2018 of the translation unit -- which is when this function is
2019 called. */
2023 /* See if any of the vtables are needed. */
2025 {
2029 }
2031 {
2032 /* If the references to this class' vtables are optimized away,
2033 still emit the appropriate debugging information. See
2034 dfs_debug_mark. */
2039 }
2041 /* The ABI requires that we emit all of the vtables if we emit any
2042 of them. */
2044 {
2045 /* Mark entities references from the virtual table as used. */
2049 {
2052 LOOKUP_NORMAL);
2054 /* It had better be all done at compile-time. */
2056 }
2058 /* Write it out. */
2062 /* Because we're only doing syntax-checking, we'll never end up
2063 actually marking the variable as written. */
2067 {
2072 }
2073 }
2075 /* Since we're writing out the vtable here, also write the debug
2076 info. */
2080 }
2082 /* A special return value from type_visibility meaning internal
2083 linkage. */
2087 /* walk_tree helper function for type_visibility. */
2089 static tree
2091 {
2094 {
2096 }
2099 {
2102 }
2107 }
2109 /* Returns the visibility of TYPE, which is the minimum visibility of its
2110 component types. */
2112 static int
2114 {
2118 }
2120 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2121 specified (or if VISIBILITY is static). If TMPL is true, this
2122 constraint is for a template argument, and takes precedence
2123 over explicitly-specified visibility on the template. */
2125 static void
2127 {
2129 {
2130 /* extern "C" declarations aren't affected by the anonymous
2131 namespace. */
2133 {
2139 {
2144 }
2148 }
2149 }
2152 {
2154 /* This visibility was not specified. */
2156 }
2157 }
2159 /* Constrain the visibility of DECL based on the visibility of its template
2160 arguments. */
2162 static void
2164 {
2165 /* If this is a template instantiation, check the innermost
2166 template args for visibility constraints. The outer template
2167 args are covered by the class check. */
2171 {
2177 else
2178 {
2186 {
2189 else
2191 }
2192 }
2195 }
2196 }
2198 /* Like c_determine_visibility, but with additional C++-specific
2199 behavior.
2201 Function-scope entities can rely on the function's visibility because
2202 it is set in start_preparsed_function.
2204 Class-scope entities cannot rely on the class's visibility until the end
2205 of the enclosing class definition.
2207 Note that because namespaces have multiple independent definitions,
2208 namespace visibility is handled elsewhere using the #pragma visibility
2209 machinery rather than by decorating the namespace declaration.
2211 The goal is for constraints from the type to give a diagnostic, and
2212 other constraints to be applied silently. */
2214 void
2216 {
2217 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2219 /* Only relevant for names with external linkage. */
2223 /* Cloned constructors and destructors get the same visibility as
2224 the underlying function. That should be set up in
2225 maybe_clone_body. */
2231 /* The decl may be a template instantiation, which could influence
2232 visibilty. */
2235 {
2237 {
2240 }
2243 }
2247 /* If DECL is a member of a class, visibility specifiers on the
2248 class can influence the visibility of the DECL. */
2252 else
2253 {
2254 /* Not a class member. */
2256 /* Virtual tables have DECL_CONTEXT set to their associated class,
2257 so they are automatically handled above. */
2262 {
2263 /* Local statics and classes get the visibility of their
2264 containing function by default, except that
2265 -fvisibility-inlines-hidden doesn't affect them. */
2268 {
2272 }
2273 else
2274 {
2278 {
2282 }
2283 else
2284 {
2288 }
2289 }
2291 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2292 but have no TEMPLATE_INFO. Their containing template
2293 function does, and the local class could be constrained
2294 by that. */
2297 }
2300 {
2301 /* Under -fvisibility-ms-compat, types are visible by default,
2302 even though their contents aren't. */
2309 else
2311 }
2313 {
2314 /* tinfo visibility is based on the type it's for. */
2315 constrain_visibility
2318 /* Give the target a chance to override the visibility associated
2319 with DECL. */
2325 }
2327 /* Template instantiations and specializations get visibility based
2330 {
2333 else
2334 {
2335 /* Set default visibility to whatever the user supplied with
2336 #pragma GCC visibility or a namespace visibility attribute. */
2339 }
2340 }
2341 }
2344 {
2345 /* If the specialization doesn't specify visibility, use the
2346 visibility from the template. */
2354 {
2358 {
2362 else
2363 {
2367 }
2368 }
2371 /* Template argument visibility outweighs #pragma or namespace
2372 visibility, but not an explicit attribute. */
2374 {
2377 {
2378 /* A class template member with explicit visibility
2379 overrides the class visibility, so we need to apply
2380 all the levels of template args directly. */
2383 {
2386 }
2387 }
2389 /* Limit visibility based on its template arguments. */
2391 }
2392 }
2393 }
2399 /* Names in an anonymous namespace get internal linkage.
2400 This might change once we implement export. */
2403 {
2404 /* Propagate anonymity from type to decl. */
2409 }
2411 /* DR 757: A type without linkage shall not be used as the type of a
2412 variable or function with linkage, unless
2413 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2414 o the variable or function is not used (3.2 [basic.def.odr]) or is
2415 defined in the same translation unit.
2417 Since non-extern "C" decls need to be defined in the same
2418 translation unit, we can make the type internal. */
2421 /* If visibility changed and DECL already has DECL_RTL, ensure
2422 symbol flags are updated. */
2429 }
2431 /* By default, static data members and function members receive
2432 the visibility of their containing class. */
2434 static void
2436 {
2442 else
2443 {
2444 /* Default to the class visibility. */
2448 }
2450 /* Give the target a chance to override the visibility associated
2451 with DECL. */
2455 /* Construction virtual tables are not exported because
2456 they cannot be referred to from other object files;
2457 their name is not standardized by the ABI. */
2463 }
2465 /* Returns true iff DECL is an inline that should get hidden visibility
2466 because of -fvisibility-inlines-hidden. */
2468 static bool
2470 {
2472 /* Don't do this for inline templates; specializations might not be
2473 inline, and we don't want them to inherit the hidden
2474 visibility. We'll set it here for all inline instantiations. */
2475 && !processing_template_decl
2480 }
2482 /* Constrain the visibility of a class TYPE based on the visibility of its
2483 field types. Warn if any fields require lesser visibility. */
2485 void
2487 {
2488 tree binfo;
2489 tree t;
2498 /* Don't warn about visibility if the class has explicit visibility. */
2504 {
2509 {
2511 {
2514 {
2519 else
2523 }
2524 else
2528 }
2529 }
2536 }
2540 {
2544 {
2546 {
2549 {
2554 else
2558 }
2559 else
2563 }
2564 }
2570 }
2571 }
2573 /* Functions for adjusting the visibility of a tagged type and its nested
2574 types and declarations when it gets a name for linkage purposes from a
2575 typedef. */
2580 /* First reset the visibility of all the types. */
2582 static void
2584 {
2589 }
2590 static void
2592 {
2594 }
2596 /* Then reset the visibility of any static data members or member
2597 functions that use those types. */
2599 static void
2601 {
2610 }
2612 static void
2614 {
2616 {
2618 {
2623 }
2625 {
2631 }
2633 {
2637 }
2640 }
2641 }
2643 static void
2645 {
2647 }
2648 void
2650 {
2653 }
2655 /* Set up our initial idea of what the linkage of DECL should be. */
2657 void
2659 {
2661 /* We've already made a decision as to how this function will
2664 {
2667 {
2671 /* A non-template inline function with external linkage will
2672 always be COMDAT. As we must eventually determine the
2673 linkage of all functions, and as that causes writes to
2674 the data mapped in from the PCH file, it's advantageous
2675 to mark the functions at this point. */
2679 {
2680 /* This function must have external linkage, as
2681 otherwise DECL_INTERFACE_KNOWN would have been
2682 set. */
2686 }
2687 }
2690 }
2691 }
2693 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2694 for DECL has not already been determined, do so now by setting
2695 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2696 function is called entities with vague linkage whose definitions
2697 are available must have TREE_PUBLIC set.
2699 If this function decides to place DECL in COMDAT, it will set
2700 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2701 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2702 callers defer that decision until it is clear that DECL is actually
2703 required. */
2705 void
2707 {
2716 /* We cannot determine what linkage to give to an entity with vague
2717 linkage until the end of the file. For example, a virtual table
2718 for a class will be defined if and only if the key method is
2719 defined in this translation unit. As a further example, consider
2720 that when compiling a translation unit that uses PCH file with
2721 "-frepo" it would be incorrect to make decisions about what
2722 entities to emit when building the PCH; those decisions must be
2723 delayed until the repository information has been processed. */
2725 /* Object file linkage for explicit instantiations is handled in
2726 mark_decl_instantiated. For static variables in functions with
2727 vague linkage, maybe_commonize_var is used.
2729 Therefore, the only declarations that should be provided to this
2730 function are those with external linkage that are:
2732 * implicit instantiations of function templates
2734 * inline function
2736 * implicit instantiations of static data members of class
2737 templates
2739 * virtual tables
2741 * typeinfo objects
2743 Furthermore, all entities that reach this point must have a
2744 definition available in this translation unit.
2746 The following assertions check these conditions. */
2748 /* Any code that creates entities with TREE_PUBLIC cleared should
2749 also set DECL_INTERFACE_KNOWN. */
2755 else
2759 /* Check that a definition of DECL is available in this translation
2760 unit. */
2763 /* Assume that DECL will not have COMDAT linkage. */
2765 /* Assume that DECL will not be imported into this translation
2766 unit. */
2769 /* See if the repository tells us whether or not to emit DECL in
2770 this translation unit. */
2775 {
2776 /* The repository indicates that this entity should be defined
2777 here. Make sure the back end honors that request. */
2779 /* Output the definition as an ordinary strong definition. */
2783 }
2786 /* We have already decided what to do with this DECL; there is no
2787 need to check anything further. */
2788 ;
2790 {
2800 /* The ABI requires that all virtual tables be emitted with
2801 COMDAT linkage. However, on systems where COMDAT symbols
2802 don't show up in the table of contents for a static
2803 archive, or on systems without weak symbols (where we
2804 approximate COMDAT linkage by using internal linkage), the
2805 linker will report errors about undefined symbols because
2806 it will not see the virtual table definition. Therefore,
2807 in the case that we know that the virtual table will be
2808 emitted in only one translation unit, we make the virtual
2809 table an ordinary definition with external linkage. */
2812 {
2813 /* CLASS_TYPE is being exported from this translation unit,
2814 so DECL should be defined here. */
2816 /* If a class is declared in a header with the "extern
2817 template" extension, then it will not be instantiated,
2818 even in translation units that would normally require
2819 it. Often such classes are explicitly instantiated in
2820 one translation unit. Therefore, the explicit
2821 instantiation must be made visible to other translation
2822 units. */
2824 else
2825 {
2826 /* The generic C++ ABI says that class data is always
2827 COMDAT, even if there is a key function. Some
2828 variants (e.g., the ARM EABI) says that class data
2829 only has COMDAT linkage if the class data might be
2830 emitted in more than one translation unit. When the
2831 key method can be inline and is inline, we still have
2832 to arrange for comdat even though
2833 class_data_always_comdat is false. */
2837 {
2838 /* The ABI requires COMDAT linkage. Normally, we
2839 only emit COMDAT things when they are needed;
2840 make sure that we realize that this entity is
2841 indeed needed. */
2844 }
2845 }
2846 }
2850 else
2852 }
2854 {
2857 {
2863 /* If -fno-rtti was specified, then we cannot be sure
2864 that RTTI information will be emitted with the
2865 virtual table of the class, so we must emit it
2866 wherever it is used. */
2869 else
2870 {
2873 {
2879 {
2882 }
2883 }
2884 else
2886 }
2887 }
2888 else
2890 }
2892 {
2893 /* DECL is an implicit instantiation of a function or static
2894 data member. */
2897 || (flag_implicit_inline_templates
2901 else
2902 /* If we are not implicitly generating templates, then mark
2903 this entity as undefined in this translation unit. */
2905 }
2907 {
2909 {
2913 {
2917 && ! flag_implement_inlines
2923 /* Always make artificials weak. */
2926 else
2928 }
2929 }
2930 else
2932 }
2933 else
2937 {
2938 /* If we are importing DECL into this translation unit, mark is
2939 an undefined here. */
2942 }
2944 {
2945 /* If we decided to put DECL in COMDAT, mark it accordingly at
2946 this point. */
2948 }
2951 }
2953 /* Return an expression that performs the destruction of DECL, which
2954 must be a VAR_DECL whose type has a non-trivial destructor, or is
2955 an array whose (innermost) elements have a non-trivial destructor. */
2957 tree
2959 {
2963 }
2965 /* Returns the initialization guard variable for the variable DECL,
2966 which has static storage duration. */
2968 tree
2970 {
2971 tree sname;
2972 tree guard;
2977 {
2978 tree guard_type;
2980 /* We use a type that is big enough to contain a mutex as well
2981 as an integer counter. */
2986 /* The guard should have the same linkage as what it guards. */
3004 }
3006 }
3008 /* Return an atomic load of src with the appropriate memory model. */
3010 static tree
3012 {
3027 }
3029 /* Return those bits of the GUARD variable that should be set when the
3030 guarded entity is actually initialized. */
3032 static tree
3034 {
3036 {
3037 /* We only set the first byte of the guard, in order to leave room
3038 for a mutex in the high-order bits. */
3041 guard);
3044 guard);
3046 }
3049 }
3051 /* Return an expression which determines whether or not the GUARD
3052 variable has already been initialized. */
3054 tree
3056 {
3057 tree guard_value;
3061 else
3064 /* Mask off all but the low bit. */
3066 {
3072 tf_warning_or_error);
3073 }
3080 tf_warning_or_error);
3081 }
3083 /* Return an expression which sets the GUARD variable, indicating that
3084 the variable being guarded has been initialized. */
3086 tree
3088 {
3089 tree guard_init;
3091 /* Set the GUARD to one. */
3097 tf_warning_or_error);
3098 }
3100 /* Returns true iff we can tell that VAR does not have a dynamic
3101 initializer. */
3103 static bool
3105 {
3106 /* If it's defined in another TU, we can't tell. */
3109 /* If it has a non-trivial destructor, registering the destructor
3110 counts as dynamic initialization. */
3113 /* If it's in this TU, its initializer has been processed, unless
3114 it's a case of self-initialization, then DECL_INITIALIZED_P is
3115 false while the initializer is handled by finish_id_expression. */
3118 /* If it has no initializer or a constant one, it's not dynamic. */
3121 }
3123 /* Returns true iff VAR is a variable that needs uses to be
3124 wrapped for possible dynamic initialization. */
3126 static bool
3128 {
3134 }
3136 /* Get the FUNCTION_DECL for the shared TLS init function for this
3137 translation unit. */
3139 static tree
3141 {
3145 {
3148 void_list_node));
3154 }
3156 }
3158 /* Get a FUNCTION_DECL for the init function for the thread_local
3159 variable VAR. The init function will be an alias to the function
3160 that initializes all the non-local TLS variables in the translation
3161 unit. The init function is only used by the wrapper function. */
3163 static tree
3165 {
3166 /* Only C++11 TLS vars need this init fn. */
3170 /* If -fno-extern-tls-init, assume that we don't need to call
3171 a tls init function for a variable defined in another TU. */
3175 /* If the variable is internal, or if we can't generate aliases,
3176 call the local init function directly. */
3183 {
3186 void_list_node));
3195 {
3197 /* If the variable is defined somewhere else and might have static
3198 initialization, make the init function a weak reference. */
3204 else
3206 }
3216 }
3218 }
3220 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3221 variable VAR. The wrapper function calls the init function (if any) for
3222 VAR and then returns a reference to VAR. The wrapper function is used
3223 in place of VAR everywhere VAR is mentioned. */
3225 tree
3227 {
3228 /* Only C++11 TLS vars need this wrapper fn. */
3235 {
3236 /* A named rvalue reference is an lvalue, so the wrapper should
3237 always return an lvalue reference. */
3246 /* The wrapper is inline and emitted everywhere var is used. */
3249 {
3251 #ifdef HAVE_GAS_HIDDEN
3252 /* Make the wrapper bind locally; there's no reason to share
3253 the wrapper between multiple shared objects. */
3256 #endif
3257 }
3263 #if 0
3264 /* We want CSE to commonize calls to the wrapper, but marking it as
3265 pure is unsafe since it has side-effects. I guess we need a new
3266 ECF flag even weaker than ECF_PURE. FIXME! */
3268 #endif
3273 }
3275 }
3277 /* At EOF, generate the definition for the TLS wrapper function FN:
3279 T& var_wrapper() {
3280 if (init_fn) init_fn();
3281 return var;
3282 } */
3284 static void
3286 {
3291 /* Only call the init fn if there might be one. */
3293 {
3295 /* If init_fn is a weakref, make sure it exists before calling. */
3297 {
3302 tf_warning_or_error);
3304 }
3308 {
3311 }
3312 }
3313 else
3314 /* If there's no initialization, the wrapper is a constant function. */
3319 }
3321 /* Start the process of running a particular set of global constructors
3322 or destructors. Subroutine of do_[cd]tors. Also called from
3323 vtv_start_verification_constructor_init_function. */
3325 static tree
3327 {
3328 tree body;
3329 tree fndecl;
3332 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3335 {
3338 #ifdef JOINER
3340 #else
3342 #endif
3345 }
3346 else
3352 NULL_TREE));
3357 /* Mark as artificial because it's not explicitly in the user's
3358 source code. */
3361 /* Mark this declaration as used to avoid spurious warnings. */
3364 /* Mark this function as a global constructor or destructor. */
3367 else
3373 }
3375 /* Finish the process of running a particular set of global constructors
3376 or destructors. Subroutine of do_[cd]tors. */
3378 static void
3380 {
3381 tree fn;
3383 /* Finish up. */
3388 {
3391 }
3392 else
3393 {
3396 }
3399 }
3401 /* The names of the parameters to the function created to handle
3402 initializations and destructions for objects with static storage
3403 duration. */
3407 /* The name of the function we create to handle initializations and
3408 destructions for objects with static storage duration. */
3411 /* The declaration for the __INITIALIZE_P argument. */
3414 /* The declaration for the __PRIORITY argument. */
3417 /* The declaration for the static storage duration function. */
3420 /* All the static storage duration functions created in this
3421 translation unit. */
3424 /* A map from priority levels to information about that priority
3425 level. There may be many such levels, so efficient lookup is
3426 important. */
3429 /* Begins the generation of the function that will handle all
3430 initialization and destruction of objects with static storage
3431 duration. The function generated takes two parameters of type
3432 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3433 nonzero, it performs initializations. Otherwise, it performs
3434 destructions. It only performs those initializations or
3435 destructions with the indicated __PRIORITY. The generated function
3436 returns no value.
3438 It is assumed that this function will only be called once per
3439 translation unit. */
3441 static tree
3443 {
3444 tree type;
3445 tree body;
3448 /* Create the identifier for this function. It will be of the form
3449 SSDF_IDENTIFIER_<number>. */
3454 NULL_TREE);
3456 /* Create the FUNCTION_DECL itself. */
3459 type);
3463 /* Put this function in the list of functions to be called from the
3464 static constructors and destructors. */
3466 {
3469 /* Take this opportunity to initialize the map from priority
3470 numbers to information about that priority level. */
3473 /*delete_value_fn=*/
3476 /* We always need to generate functions for the
3477 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3478 priorities later, we'll be sure to find the
3479 DEFAULT_INIT_PRIORITY. */
3481 }
3485 /* Create the argument list. */
3486 initialize_p_decl = cp_build_parm_decl
3489 priority_decl = cp_build_parm_decl
3496 /* Put the function in the global scope. */
3499 /* Start the function itself. This is equivalent to declaring the
3500 function as:
3502 static void __ssdf (int __initialize_p, init __priority_p);
3504 It is static because we only need to call this function from the
3505 various constructor and destructor functions for this module. */
3508 SF_PRE_PARSED);
3510 /* Set up the scope of the outermost block in the function. */
3514 }
3516 /* Finish the generation of the function which performs initialization
3517 and destruction of objects with static storage duration. After
3518 this point, no more such objects can be created. */
3520 static void
3522 {
3523 /* Close out the function. */
3526 }
3528 /* Return the information about the indicated PRIORITY level. If no
3529 code to handle this level has yet been generated, generate the
3530 appropriate prologue. */
3532 static priority_info
3534 {
3535 priority_info pi;
3536 splay_tree_node n;
3541 {
3542 /* Create a new priority information structure, and insert it
3543 into the map. */
3550 }
3551 else
3555 }
3557 /* The effective initialization priority of a DECL. */
3559 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3560 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3561 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3563 /* Whether a DECL needs a guard to protect it against multiple
3564 initialization. */
3566 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3567 || DECL_ONE_ONLY (decl) \
3568 || DECL_WEAK (decl)))
3570 /* Called from one_static_initialization_or_destruction(),
3571 via walk_tree.
3572 Walks the initializer list of a global variable and looks for
3573 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3574 and that have their DECL_CONTEXT() == NULL.
3575 For each such temporary variable, set their DECL_CONTEXT() to
3576 the current function. This is necessary because otherwise
3577 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3578 when trying to refer to a temporary variable that does not have
3579 it's DECL_CONTECT() properly set. */
3580 static tree
3584 {
3588 {
3589 tree var;
3597 }
3600 }
3602 /* Set up to handle the initialization or destruction of DECL. If
3603 INITP is nonzero, we are initializing the variable. Otherwise, we
3604 are destroying it. */
3606 static void
3608 {
3610 tree guard;
3612 /* If we are supposed to destruct and there's a trivial destructor,
3613 nothing has to be done. */
3618 /* Trick the compiler into thinking we are at the file and line
3619 where DECL was declared so that error-messages make sense, and so
3620 that the debugger will show somewhat sensible file and line
3621 information. */
3624 /* Make sure temporary variables in the initialiser all have
3625 their DECL_CONTEXT() set to a value different from NULL_TREE.
3626 This can happen when global variables initializers are built.
3627 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3628 the temporary variables that might have been generated in the
3629 accompanying initializers is NULL_TREE, meaning the variables have been
3630 declared in the global namespace.
3631 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3632 of the temporaries are set to the current function decl. */
3634 fix_temporary_vars_context_r,
3635 NULL);
3637 /* Because of:
3639 [class.access.spec]
3641 Access control for implicit calls to the constructors,
3642 the conversion functions, or the destructor called to
3643 create and destroy a static data member is performed as
3644 if these calls appeared in the scope of the member's
3645 class.
3647 we pretend we are in a static member function of the class of
3648 which the DECL is a member. */
3650 {
3653 }
3655 /* Assume we don't need a guard. */
3657 /* We need a guard if this is an object with external linkage that
3658 might be initialized in more than one place. (For example, a
3659 static data member of a template, when the data member requires
3660 construction.) */
3662 {
3663 tree guard_cond;
3667 /* When using __cxa_atexit, we just check the GUARD as we would
3668 for a local static. */
3670 {
3671 /* When using __cxa_atexit, we never try to destroy
3672 anything from a static destructor. */
3675 }
3676 /* If we don't have __cxa_atexit, then we will be running
3677 destructors from .fini sections, or their equivalents. So,
3678 we need to know how many times we've tried to initialize this
3679 object. We do initializations only if the GUARD is zero,
3680 i.e., if we are the first to initialize the variable. We do
3681 destructions only if the GUARD is one, i.e., if we are the
3682 last to destroy the variable. */
3684 guard_cond
3686 EQ_EXPR,
3688 guard,
3690 tf_warning_or_error),
3691 integer_one_node,
3692 tf_warning_or_error);
3693 else
3694 guard_cond
3696 EQ_EXPR,
3698 guard,
3700 tf_warning_or_error),
3701 integer_zero_node,
3702 tf_warning_or_error);
3706 }
3709 /* If we're using __cxa_atexit, we have not already set the GUARD,
3710 so we must do so now. */
3714 /* Perform the initialization or destruction. */
3716 {
3718 {
3721 {
3725 }
3726 }
3728 /* If we're using __cxa_atexit, register a function that calls the
3729 destructor for the object. */
3732 }
3733 else
3736 /* Finish the guard if-stmt, if necessary. */
3738 {
3741 }
3743 /* Now that we're done with DECL we don't need to pretend to be a
3744 member of its class any longer. */
3747 }
3749 /* Generate code to do the initialization or destruction of the decls in VARS,
3750 a TREE_LIST of VAR_DECL with static storage duration.
3751 Whether initialization or destruction is performed is specified by INITP. */
3753 static void
3755 {
3758 /* Build the outer if-stmt to check for initialization or destruction. */
3762 EQ_EXPR,
3763 initialize_p_decl,
3764 cond,
3765 tf_warning_or_error);
3768 /* To make sure dynamic construction doesn't access globals from other
3769 compilation units where they might not be yet constructed, for
3770 -fsanitize=address insert __asan_before_dynamic_init call that
3771 prevents access to either all global variables that need construction
3772 in other compilation units, or at least those that haven't been
3773 initialized yet. Variables that need dynamic construction in
3774 the current compilation unit are kept accessible. */
3781 tree priority_if_stmt;
3783 priority_info pi;
3785 /* If we don't need a destructor, there's nothing to do. Avoid
3786 creating a possibly empty if-stmt. */
3788 {
3791 }
3793 /* Remember that we had an initialization or finalization at this
3794 priority. */
3799 else
3802 /* Conditionalize this initialization on being in the right priority
3803 and being initializing/finalizing appropriately. */
3806 EQ_EXPR,
3807 priority_decl,
3809 tf_warning_or_error);
3812 /* Process initializers with same priority. */
3816 /* Do one initialization or destruction. */
3820 /* Finish up the priority if-stmt body. */
3826 /* Revert what __asan_before_dynamic_init did by calling
3827 __asan_after_dynamic_init. */
3831 /* Finish up the init/destruct if-stmt body. */
3834 }
3836 /* VARS is a list of variables with static storage duration which may
3837 need initialization and/or finalization. Remove those variables
3838 that don't really need to be initialized or finalized, and return
3839 the resulting list. The order in which the variables appear in
3840 VARS is in reverse order of the order in which they should actually
3841 be initialized. The list we return is in the unreversed order;
3842 i.e., the first variable should be initialized first. */
3844 static tree
3846 {
3851 {
3856 /* Deal gracefully with error. */
3858 {
3861 }
3863 /* The only things that can be initialized are variables. */
3866 /* If this object is not defined, we don't need to do anything
3867 here. */
3869 {
3872 }
3874 /* Also, if the initializer already contains errors, we can bail
3875 out now. */
3878 {
3881 }
3883 /* This variable is going to need initialization and/or
3884 finalization, so we add it to the list. */
3888 }
3891 }
3893 /* Make sure we have told the back end about all the variables in
3894 VARS. */
3896 static void
3898 {
3899 tree v;
3902 {
3905 {
3908 }
3909 }
3910 }
3912 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
3913 (otherwise) that will initialize all global objects with static
3914 storage duration having the indicated PRIORITY. */
3916 static void
3919 {
3921 tree fndecl;
3922 tree body;
3926 /* ??? */
3927 /* Was: locus->line++; */
3929 /* We use `I' to indicate initialization and `D' to indicate
3930 destruction. */
3933 /* We emit the function lazily, to avoid generating empty
3934 global constructors and destructors. */
3937 /* For Objective-C++, we may need to initialize metadata found in this module.
3938 This must be done _before_ any other static initializations. */
3941 {
3944 }
3946 /* Call the static storage duration function with appropriate
3947 arguments. */
3949 {
3950 /* Calls to pure or const functions will expand to nothing. */
3952 {
3953 tree call;
3960 constructor_p),
3962 priority),
3963 NULL_TREE);
3965 }
3966 }
3968 /* Close out the function. */
3971 }
3973 /* Generate constructor and destructor functions for the priority
3974 indicated by N. */
3976 static int
3978 {
3983 /* Generate the functions themselves, but only if they are really
3984 needed. */
3990 /* Keep iterating. */
3992 }
3994 /* Return C++ property of T, based on given operation OP. */
3996 static int
3998 {
4000 {
4002 {
4010 }
4027 }
4028 }
4030 /* Collect source file references recursively, starting from NAMESPC. */
4032 static void
4034 {
4035 /* Iterate over names in this name space. */
4038 ;
4041 else
4043 }
4045 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4046 starting from NAMESPC. */
4048 static void
4050 {
4053 /* Collect decls from this namespace. This will skip
4054 NAMESPACE_DECLs (both aliases and regular, it cannot tell). */
4057 /* Now scan for namespace children, and dump them. */
4061 }
4063 /* Returns true iff there is a definition available for variable or
4064 function DECL. */
4066 bool
4068 {
4071 /* A pending instantiation of a friend temploid is defined. */
4075 else
4076 {
4079 }
4080 }
4082 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4084 [expr.const]
4086 An integral constant-expression can only involve ... const
4087 variables of integral or enumeration types initialized with
4088 constant expressions ...
4090 C++0x also allows constexpr variables and temporaries initialized
4091 with constant expressions. We handle the former here, but the latter
4092 are just folded away in cxx_eval_constant_expression.
4094 The standard does not require that the expression be non-volatile.
4095 G++ implements the proposed correction in DR 457. */
4097 bool
4099 {
4103 /* We don't know if a template static data member is initialized with
4104 a constant expression until we instantiate its initializer. Even
4105 in the case of a constexpr variable, we can't treat it as a
4106 constant until its initializer is complete in case it's used in
4107 its own initializer. */
4110 }
4112 /* Returns true if DECL could be a symbolic constant variable, depending on
4113 its initializer. */
4115 bool
4117 {
4124 /* A proxy isn't constant. */
4131 else
4136 /* We know the initializer, and it isn't constant. */
4138 else
4140 }
4142 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4143 called from grokfndecl and grokvardecl; in all modes it is called from
4144 cp_write_global_declarations. */
4146 void
4148 {
4150 /* In C++11 it's ok if the decl is defined. */
4154 /* The type that got us on no_linkage_decls must have gotten a name for
4157 /* The type might end up having a typedef name for linkage purposes. */
4160 {
4168 /* DRs 132, 319 and 389 seem to indicate types with
4169 no linkage can only be used to declare extern "C"
4170 entities. Since it's not always an error in the
4171 ISO C++ 90 Standard, we only issue a warning. */
4173 "with no linkage used to declare variable %q#D with "
4175 else
4178 decl);
4183 }
4185 {
4188 "%q#D, declared using local type "
4190 }
4194 else
4197 }
4199 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4201 static void
4203 {
4205 }
4207 /* Clear DECL_EXTERNAL for NODE. */
4209 static bool
4211 {
4214 }
4216 /* Build up the function to run dynamic initializers for thread_local
4217 variables in this translation unit and alias the init functions for the
4218 individual variables to it. */
4220 static void
4222 {
4232 boolean_type_node);
4247 tf_warning_or_error);
4250 boolean_true_node,
4251 tf_warning_or_error));
4253 {
4258 /* Output init aliases even with -fno-extern-tls-init. */
4260 {
4264 cgraph_node *alias
4268 }
4269 }
4275 }
4277 /* We're at the end of compilation, so generate any mangling aliases that
4278 we've been saving up, if DECL is going to be output and ID2 isn't
4279 already taken by another declaration. */
4281 static void
4283 {
4284 /* If there's a declaration already using this mangled name,
4285 don't create a compatibility alias that conflicts. */
4292 /* Don't create an alias to an unreferenced function. */
4304 else
4306 }
4308 /* Note that we might want to emit an alias with the symbol ID2 for DECL at
4309 the end of translation, for compatibility across bugs in the mangling
4310 implementation. */
4312 void
4314 {
4316 {
4319 else
4320 {
4323 }
4324 }
4325 }
4327 /* Emit all mangling aliases that were deferred up to this point. */
4329 void
4331 {
4333 {
4337 }
4339 }
4341 /* The entire file is now complete. If requested, dump everything
4342 to a file. */
4344 static void
4346 {
4347 dump_flags_t flags;
4349 {
4352 }
4353 }
4357 /* Check the deallocation functions for CODE to see if we want to warn that
4358 only one was defined. */
4360 static void
4362 {
4368 {
4370 /* We're only interested in usual deallocation functions. */
4375 else
4377 }
4384 }
4386 /* Check the global deallocation functions to see if we want to warn about
4387 defining unsized without sized (or vice versa). */
4389 static void
4391 {
4396 }
4398 /* Earlier we left PTRMEM_CST in variable initializers alone so that we could
4399 look them up when evaluating non-type template parameters. Now we need to
4400 lower them to something the back end can understand. */
4402 static void
4404 {
4407 {
4411 }
4412 }
4414 /* This routine is called at the end of compilation.
4415 Its job is to create all the code needed to initialize and
4416 destroy the global aggregates. We do the destruction
4417 first, since that way we only need to reverse the decls once. */
4419 void
4421 {
4422 tree vars;
4427 tree decl;
4432 /* Bad parse errors. Just forget about it. */
4437 /* This is the point to write out a PCH if we're doing that.
4438 In that case we do not want to do anything else. */
4440 {
4441 /* Mangle all symbols at PCH creation time. */
4449 /* Ensure even the callers don't try to finalize the CU. */
4452 }
4459 /* Handle -fdump-ada-spec[-slim] */
4461 {
4464 else
4468 }
4470 /* FIXME - huh? was input_line -= 1;*/
4472 /* We now have to write out all the stuff we put off writing out.
4473 These include:
4475 o Template specializations that we have not yet instantiated,
4476 but which are needed.
4477 o Initialization and destruction for non-local objects with
4478 static storage duration. (Local objects with static storage
4479 duration are initialized when their scope is first entered,
4480 and are cleaned up via atexit.)
4481 o Virtual function tables.
4483 All of these may cause others to be needed. For example,
4484 instantiating one function may cause another to be needed, and
4485 generating the initializer for an object may cause templates to be
4486 instantiated, etc., etc. */
4490 do
4491 {
4492 tree t;
4493 tree decl;
4497 /* If there are templates that we've put off instantiating, do
4498 them now. */
4502 /* Write out virtual tables as required. Writing out the
4503 virtual table for a template class may cause the
4504 instantiation of members of that class. If we write out
4505 vtables then we remove the class from our list so we don't
4506 have to look at it again. */
4510 {
4513 }
4515 /* Write out needed type info variables. We have to be careful
4516 looping through unemitted decls, because emit_tinfo_decl may
4517 cause other variables to be needed. New elements will be
4518 appended, and we remove from the vector those that actually
4519 get emitted. */
4523 {
4526 }
4528 /* The list of objects with static storage duration is built up
4529 in reverse order. We clear STATIC_AGGREGATES so that any new
4530 aggregates added during the initialization of these will be
4531 initialized in the correct order when we next come around the
4532 loop. */
4536 {
4537 /* We need to start a new initialization function each time
4538 through the loop. That's because we need to know which
4539 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4540 isn't computed until a function is finished, and written
4541 out. That's a deficiency in the back end. When this is
4542 fixed, these initialization functions could all become
4543 inline, with resulting performance improvements. */
4544 tree ssdf_body;
4546 /* Set the line and file, so that it is obviously not from
4547 the source file. */
4551 /* Make sure the back end knows about all the variables. */
4554 /* First generate code to do all the initializations. */
4558 /* Then, generate code to do all the destructions. Do these
4559 in reverse order so that the most recently constructed
4560 variable is the first destroyed. If we're using
4561 __cxa_atexit, then we don't need to do this; functions
4562 were registered at initialization time to destroy the
4563 local statics. */
4565 {
4568 }
4569 else
4572 /* Finish up the static storage duration function for this
4573 round. */
4577 /* All those initializations and finalizations might cause
4578 us to need more inline functions, more template
4579 instantiations, etc. */
4581 ssdf_count++;
4582 /* ??? was: locus_at_end_of_parsing.line++; */
4583 }
4585 /* Now do the same for thread_local variables. */
4588 /* Go through the set of inline functions whose bodies have not
4589 been emitted yet. If out-of-line copies of these functions
4590 are required, emit them. */
4592 {
4593 /* Does it need synthesizing? */
4596 {
4597 /* Even though we're already at the top-level, we push
4598 there again. That way, when we pop back a few lines
4599 hence, all of our state is restored. Otherwise,
4600 finish_function doesn't clean things up, and we end
4601 up with CURRENT_FUNCTION_DECL set. */
4603 /* The decl's location will mark where it was first
4604 needed. Save that so synthesize method can indicate
4605 where it was needed from, in case of error */
4610 }
4620 /* We lie to the back end, pretending that some functions
4621 are not defined when they really are. This keeps these
4622 functions from being put out unnecessarily. But, we must
4623 stop lying when the functions are referenced, or if they
4624 are not comdat since they need to be put out now. If
4625 DECL_INTERFACE_KNOWN, then we have already set
4626 DECL_EXTERNAL appropriately, so there's no need to check
4627 again, and we do not want to clear DECL_EXTERNAL if a
4628 previous call to import_export_decl set it.
4630 This is done in a separate for cycle, because if some
4631 deferred function is contained in another deferred
4632 function later in deferred_fns varray,
4633 rest_of_compilation would skip this function and we
4634 really cannot expand the same function twice. */
4639 {
4645 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4646 group, we need to mark all symbols in the same comdat group
4647 that way. */
4655 }
4657 /* If we're going to need to write this function out, and
4658 there's already a body for it, create RTL for it now.
4659 (There might be no body if this is a method we haven't
4660 gotten around to synthesizing yet.) */
4665 {
4666 /* We will output the function; no longer consider it in this
4667 loop. */
4669 /* Generate RTL for this function now that we know we
4670 need it. */
4672 /* If we're compiling -fsyntax-only pretend that this
4673 function has been written out so that we don't try to
4674 expand it again. */
4678 }
4679 }
4684 /* Static data members are just like namespace-scope globals. */
4686 {
4688 /* Don't write it out if we haven't seen a definition. */
4692 /* If this static data member is needed, provide it to the
4693 back end. */
4696 }
4702 retries++;
4703 }
4710 /* All used inline functions must have a definition at this point. */
4712 {
4715 /* If the definition actually was available here, then the
4716 fact that the function was not defined merely represents
4717 that for some reason (use of a template repository,
4718 #pragma interface, etc.) we decided not to emit the
4719 definition here. */
4721 /* Don't complain if the template was defined. */
4725 {
4728 /* Avoid a duplicate warning from check_global_declaration. */
4730 }
4731 }
4733 /* So must decls that use a type with no linkage. */
4739 /* Then, do the Objective-C stuff. This is where all the
4740 Objective-C module stuff gets generated (symtab,
4741 class/protocol/selector lists etc). This must be done after C++
4742 templates, destructors etc. so that selectors used in C++
4743 templates are properly allocated. */
4747 /* We give C linkage to static constructors and destructors. */
4750 /* Generate initialization and destruction functions for all
4751 priorities for which they are required. */
4754 generate_ctor_and_dtor_functions_for_priority,
4757 /* If this is obj-c++ and we need a static init, call
4758 generate_ctor_or_dtor_function. */
4760 DEFAULT_INIT_PRIORITY,
4763 /* We're done with the splay-tree now. */
4767 /* Generate any missing aliases. */
4770 /* We're done with static constructors, so we can go back to "C++"
4771 linkage now. */
4775 {
4779 }
4786 /* The entire file is now complete. If requested, dump everything
4787 to a file. */
4791 {
4794 }
4799 /* Indicate that we're done with front end processing. */
4801 }
4803 /* Perform any post compilation-proper cleanups for the C++ front-end.
4804 This should really go away. No front-end should need to do
4805 anything past the compilation process. */
4807 void
4809 {
4813 {
4814 /* Generate the special constructor initialization function that
4815 calls __VLTRegisterPairs, and give it a very high
4816 initialization priority. This must be done after
4817 finalize_compilation_unit so that we have accurate
4818 information about which vtable will actually be emitted. */
4820 }
4828 }
4830 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
4831 function to call in parse-tree form; it has not yet been
4832 semantically analyzed. ARGS are the arguments to the function.
4833 They have already been semantically analyzed. This may change
4834 ARGS. */
4836 tree
4838 tsubst_flags_t complain)
4839 {
4840 tree orig_fn;
4842 tree expr;
4843 tree object;
4849 {
4858 /* Transform the arguments and add the implicit "this"
4859 parameter. That must be done before the FN is transformed
4860 because we depend on the form of FN. */
4864 {
4868 }
4869 /* Now that the arguments are done, transform FN. */
4871 }
4873 /* A qualified name corresponding to a bound pointer-to-member is
4874 represented as an OFFSET_REF:
4876 struct B { void g(); };
4877 void (B::*p)();
4878 void B::g() { (this->*p)(); } */
4880 {
4884 complain);
4886 }
4890 else
4899 }
4902 void
4904 {
4909 {
4913 {
4916 }
4917 }
4918 }
4920 /* Return true if function DECL can be inlined. This is used to force
4921 instantiation of methods that might be interesting for inlining. */
4922 bool
4924 {
4930 /* When optimizing, we might inline everything when flatten
4931 attribute or heuristics inlining for size or autoinlining
4932 is used. */
4934 }
4936 /* Normally, we can wait until instantiation-time to synthesize DECL.
4937 However, if DECL is a static data member initialized with a constant
4938 or a constexpr function, we need it right now because a reference to
4939 such a data member or a call to such function is not value-dependent.
4940 For a function that uses auto in the return type, we need to instantiate
4941 it to find out its type. For OpenMP user defined reductions, we need
4942 them instantiated for reduction clauses which inline them by hand
4943 directly. */
4945 static void
4947 {
4956 {
4957 /* Instantiating a function will result in garbage collection. We
4958 must treat this situation as if we were within the body of a
4959 function so as to avoid collecting live data only referenced from
4960 the stack (such as overload resolution candidates). */
4965 }
4966 }
4968 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
4969 If DECL is a specialization or implicitly declared class member,
4970 generate the actual definition. Return false if something goes
4971 wrong, true otherwise. */
4973 bool
4975 {
4976 /* If DECL is a BASELINK for a single function, then treat it just
4977 like the DECL for the function. Otherwise, if the BASELINK is
4978 for an overloaded function, we don't know which function was
4979 actually used until after overload resolution. */
4981 {
4986 }
4988 /* Set TREE_USED for the benefit of -Wunused. */
4990 /* And for structured bindings also the underlying decl. */
5000 /* Mark enumeration types as used. */
5010 {
5014 /* We mark a lambda conversion op as deleted if we can't
5015 generate it properly; see maybe_add_lambda_conv_op. */
5018 {
5022 }
5024 }
5030 /* We can only check DECL_ODR_USED on variables or functions with
5031 DECL_LANG_SPECIFIC set, and these are also the only decls that we
5032 might need special handling for. */
5036 {
5041 }
5043 /* We only want to do this processing once. We don't need to keep trying
5044 to instantiate inline templates, because unit-at-a-time will make sure
5045 we get them compiled before functions that want to inline them. */
5049 /* Normally, we can wait until instantiation-time to synthesize DECL.
5050 However, if DECL is a static data member initialized with a constant
5051 or a constexpr function, we need it right now because a reference to
5052 such a data member or a call to such function is not value-dependent.
5053 For a function that uses auto in the return type, we need to instantiate
5054 it to find out its type. For OpenMP user defined reductions, we need
5055 them instantiated for reduction clauses which inline them by hand
5056 directly. */
5062 /* Check this too in case we're within instantiate_non_dependent_expr. */
5071 {
5075 }
5077 /* If we don't need a value, then we don't need to synthesize DECL. */
5085 /* DR 757: A type without linkage shall not be used as the type of a
5086 variable or function with linkage, unless
5087 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5088 o the variable or function is not used (3.2 [basic.def.odr]) or is
5089 defined in the same translation unit. */
5096 {
5098 /* There's no way to define a local extern, and adding it to
5099 the vector interferes with GC, so give an error now. */
5101 else
5103 }
5107 /* Remember it, so we can check it was defined. */
5110 /* Is it a synthesized method that needs to be synthesized? */
5114 /* A function defaulted outside the class is synthesized either by
5115 cp_finish_decl or instantiate_decl. */
5118 {
5119 /* Defer virtual destructors so that thunks get the right
5120 linkage. */
5122 {
5125 }
5127 /* Remember the current location for a function we will end up
5128 synthesizing. Then we can inform the user where it was
5129 required in the case of error. */
5132 /* Synthesizing an implicitly defined member function will result in
5133 garbage collection. We must treat this situation as if we were
5134 within the body of a function so as to avoid collecting live data
5135 on the stack (such as overload resolution candidates).
5137 We could just let cp_write_global_declarations handle synthesizing
5138 this function by adding it to deferred_fns, but doing
5139 it at the use site produces better error messages. */
5143 /* If this is a synthesized method we don't need to
5144 do the instantiation test below. */
5145 }
5151 /* If this is a function or variable that is an instance of some
5152 template, we now know that we will need to actually do the
5153 instantiation. We check that DECL is not an explicit
5154 instantiation because that is not checked in instantiate_decl.
5156 We put off instantiating functions in order to improve compile
5157 times. Maintaining a stack of active functions is expensive,
5158 and the inliner knows to instantiate any functions it might
5159 need. Therefore, we always try to defer instantiation. */
5160 {
5165 }
5168 }
5170 bool
5172 {
5174 }
5176 tree
5178 {
5180 }
5182 tree
5184 {
5185 tree fn;
5193 }