| blob | 74ba380c44df0db2d44939deea6b1a7c146a4f98 |
1 /* Process declarations and variables for C++ compiler.
2 Copyright (C) 1988-2015 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. */
63 /* This structure contains information about the initializations
64 and/or destructions required for a particular priority level. */
66 /* Nonzero if there have been any initializations at this priority
67 throughout the translation unit. */
69 /* Nonzero if there have been any destructions at this priority
70 throughout the translation unit. */
95 /* A list of static class variables. This is needed, because a
96 static class variable can be declared inside the class without
97 an initializer, and then initialized, statically, outside the class. */
100 /* A list of functions which were declared inline, but which we
101 may need to emit outline anyway. */
104 /* A list of decls that use types with no linkage, which we need to make
105 sure are defined. */
108 /* A vector of alternating decls and identifiers, where the latter
109 is to be an alias for the former if the former is defined. */
112 /* Nonzero if we're done parsing and into end-of-file activities. */
115 \f
117 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a
118 FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers
119 that apply to the function). */
121 tree
123 cp_ref_qualifier rqual)
124 {
125 tree raises;
126 tree attrs;
155 }
157 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its
158 return type changed to NEW_RET. */
160 tree
162 {
163 tree newtype;
176 {
181 }
182 else
183 newtype = build_method_type_directly
195 }
197 /* Build a PARM_DECL with NAME and TYPE, and set DECL_ARG_TYPE
198 appropriately. */
200 tree
202 {
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 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;
367 {
374 }
380 /* If they have an `operator[]', use that. */
382 {
388 }
389 else
390 {
393 /* Otherwise, create an ARRAY_REF for a pointer or array type.
394 It is a little-known fact that, if `a' is an array and `i' is
395 an int, you can write `i[a]', which means the same thing as
396 `a[i]'. */
399 else
404 else
419 else
420 {
424 }
430 }
435 }
437 /* Given the cast expression EXP, checking out its validity. Either return
438 an error_mark_node if there was an unavoidable error, return a cast to
439 void for trying to delete a pointer w/ the value 0, or return the
440 call to delete. If DOING_VEC is true, we handle things differently
441 for doing an array delete.
442 Implements ARM $5.3.4. This is called from the parser. */
444 tree
446 tsubst_flags_t complain)
447 {
454 {
460 }
462 /* An array can't have been allocated by new, so complain. */
469 {
473 }
477 /* As of Valley Forge, you can delete a pointer to const. */
479 /* You can't delete functions. */
481 {
485 }
487 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */
489 {
492 }
494 /* Deleting a pointer with the value zero is valid and has no effect. */
500 sfk_deleting_destructor,
502 else
505 complain);
506 }
508 /* Report an error if the indicated template declaration is not the
509 sort of thing that should be a member template. */
511 void
513 {
514 tree decl;
523 {
524 /* The parser rejects template declarations in local classes
525 (with the exception of generic lambdas). */
527 /* The parser rejects any use of virtual in a function template. */
531 /* The debug-information generating code doesn't know what to do
532 with member templates. */
534 }
537 else
539 }
541 /* Return true iff TYPE is a valid Java parameter or return type. */
543 static bool
545 {
552 {
555 {
564 {
570 }
572 }
573 }
575 }
577 /* For a METHOD in a Java class CTYPE, return true if
578 the parameter and return types are valid Java types.
579 Otherwise, print appropriate error messages, and return false. */
581 bool
583 {
589 {
593 }
602 {
605 {
610 }
611 }
613 }
615 /* Sanity check: report error if this function FUNCTION is not
616 really a member of the class (CTYPE) it is supposed to belong to.
617 TEMPLATE_PARMS is used to specify the template parameters of a member
618 template passed as FUNCTION_DECL. If the member template is passed as a
619 TEMPLATE_DECL, it can be NULL since the parameters can be extracted
620 from the declaration. If the function is not a function template, it
621 must be NULL.
622 It returns the original declaration for the function, NULL_TREE if
623 no declaration was found, error_mark_node if an error was emitted. */
625 tree
627 {
630 tree pushed_scope;
636 /* Since this is a specialization of a member template,
637 we're not going to find the declaration in the class.
638 For example, in:
640 struct S { template <typename T> void f(T); };
641 template <> void S::f(int);
643 we're not going to find `S::f(int)', but there's no
644 reason we should, either. We let our callers know we didn't
645 find the method, but we don't complain. */
648 /* Basic sanity check: for a template function, the template parameters
649 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */
651 {
655 {
659 }
661 }
663 /* OK, is this a definition of a member template? */
666 /* [temp.mem]
668 A destructor shall not be a member template. */
670 {
673 }
675 /* We must enter the scope here, because conversion operators are
676 named by target type, and type equivalence relies on typenames
677 resolving within the scope of CTYPE. */
681 {
689 {
696 /* We cannot simply call decls_match because this doesn't
697 work for static member functions that are pretending to
698 be methods, and because the name may have been changed by
699 asm("new_name"). */
701 /* Get rid of the this parameter on functions that become
702 static. */
707 /* A member template definition only matches a member template
708 declaration. */
712 /* ref-qualifier or absence of same must match. */
717 // Include constraints in the match.
721 /* While finding a match, same types and params are not enough
722 if the function is versioned. Also check version ("target")
723 attributes. */
728 && (!is_template
738 }
740 {
744 }
755 {
760 {
762 {
765 {
768 }
769 }
770 else
772 }
777 else
780 }
781 }
784 else
791 }
793 /* DECL is a function with vague linkage. Remember it so that at the
794 end of the translation unit we can decide whether or not to emit
795 it. */
797 void
799 {
802 }
804 /* As above, but for variable template instantiations. */
806 void
808 {
810 }
812 /* We have just processed the DECL, which is a static data member.
813 The other parameters are as for cp_finish_decl. */
815 void
818 tree asmspec_tree,
820 {
823 /* We cannot call pushdecl here, because that would fill in the
824 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do
825 the right thing, namely, to put this decl out straight away. */
831 /* We already complained about the template definition. */
835 else
839 {
845 }
854 }
856 /* DECLARATOR and DECLSPECS correspond to a class member. The other
857 parameters are as for cp_finish_decl. Return the DECL for the
858 class member declared. */
860 tree
864 tree asmspec_tree,
865 tree attrlist)
866 {
867 tree value;
870 tree name;
880 /* friend or constructor went bad. */
886 {
889 }
891 /* Pass friendly classes back. */
899 {
901 {
904 }
909 value);
910 }
912 /* Stash away type declarations. */
914 {
919 {
922 /* If this is a typedef that names the class for linkage purposes
923 (7.1.3p8), apply any attributes directly to the type. */
929 }
936 /* It's important that push_template_decl below follows
937 set_underlying_type above so that the created template
938 carries the properly set type of VALUE. */
944 }
949 {
952 }
958 {
960 {
962 {
966 }
968 {
970 {
974 }
975 }
979 {
984 else
986 value);
987 }
988 else
989 {
993 value);
994 else
996 value);
997 }
998 }
1003 }
1005 /* Pass friend decls back. */
1011 /* Need to set this before push_template_decl. */
1016 {
1020 }
1027 else
1031 {
1056 /* Pass friends back this way. */
1065 }
1067 }
1069 /* Like `grokfield', but for bitfields.
1070 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */
1072 tree
1075 tree attrlist)
1076 {
1084 /* Pass friendly classes back. */
1091 {
1094 }
1097 {
1100 }
1102 /* Usually, finish_struct_1 catches bitfields with invalid types.
1103 But, in the case of bitfields with function type, we confuse
1104 ourselves into thinking they are member functions, so we must
1105 check here. */
1107 {
1111 }
1114 {
1118 }
1121 {
1124 }
1128 {
1129 /* The width must be an integer type. */
1136 }
1144 }
1146 \f
1147 /* Returns true iff ATTR is an attribute which needs to be applied at
1148 instantiation time rather than template definition time. */
1150 static bool
1152 {
1156 tree arg;
1159 /* Unknown attribute. */
1162 /* Attribute weak handling wants to write out assembly right away. */
1166 /* Attribute unused is applied directly, as it appertains to
1167 decls. */
1171 /* Attribute tls_model wants to modify the symtab. */
1175 /* #pragma omp declare simd attribute needs to be always deferred. */
1180 /* An attribute pack is clearly dependent. */
1184 /* If any of the arguments are dependent expressions, we can't evaluate
1185 the attribute until instantiation time. */
1187 {
1190 /* If the first attribute argument is an identifier, only consider
1191 second and following arguments. Attributes like mode, format,
1192 cleanup and several target specific attributes aren't late
1193 just because they have an IDENTIFIER_NODE as first argument. */
1200 }
1205 {
1208 /* We can't apply any attributes to a completely unknown type until
1209 instantiation time. */
1215 /* Also defer most attributes on dependent types. This is not
1216 necessary in all cases, but is the better default. */
1218 /* But some attributes specifically apply to templates. */
1223 else
1225 }
1226 else
1228 }
1230 /* ATTR_P is a list of attributes. Remove any attributes which need to be
1231 applied at instantiation time and return them. If IS_DEPENDENT is true,
1232 the declaration itself is dependent, so all attributes should be applied
1233 at instantiation time. */
1235 static tree
1237 {
1246 {
1248 {
1254 }
1255 else
1257 }
1260 }
1262 /* Remove any late attributes from the list in ATTR_P and attach them to
1263 DECL_P. */
1265 static void
1267 {
1279 else
1284 /* Merge the late attributes at the beginning with the attribute
1285 list. */
1290 {
1291 /* We've added new attributes directly to the main variant, so
1292 now we need to update all of the other variants to include
1293 these new attributes. */
1294 tree variant;
1297 {
1300 }
1301 }
1302 }
1304 /* Return true iff ATTRS are acceptable attributes to be applied in-place
1305 to a typedef which gives a previously anonymous class or enum a name for
1306 linkage purposes. */
1308 bool
1310 {
1312 {
1316 }
1318 }
1320 /* Like reconstruct_complex_type, but handle also template trees. */
1322 tree
1324 {
1329 {
1333 }
1335 {
1339 }
1341 {
1344 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the
1345 element type qualification will be handled by the recursive
1346 cp_reconstruct_complex_type call and cp_build_qualified_type
1347 for ARRAY_TYPEs changes the element type. */
1349 }
1351 {
1358 }
1360 {
1363 /* The build_method_type_directly() routine prepends 'this' to argument list,
1364 so we must compensate by getting rid of it. */
1365 outer
1366 = build_method_type_directly
1369 }
1371 {
1374 }
1375 else
1386 }
1388 /* Replaces any constexpr expression that may be into the attributes
1389 arguments with their reduced value. */
1391 static void
1393 {
1397 tree attr;
1399 {
1400 tree arg;
1402 {
1406 }
1407 }
1408 }
1410 /* Return true if TYPE is an OpenMP mappable type. */
1411 bool
1413 {
1414 /* Mappable type has to be complete. */
1417 /* Arrays have mappable type if the elements have mappable type. */
1420 /* A mappable type cannot contain virtual members. */
1423 /* All data members must be non-static. */
1425 {
1426 tree field;
1430 /* All fields must have mappable types. */
1434 }
1436 }
1438 /* Like decl_attributes, but handle C++ complexity. */
1440 void
1442 {
1447 /* Add implicit "omp declare target" attribute if requested. */
1452 {
1467 else
1470 }
1473 {
1478 }
1486 {
1487 attributes
1491 }
1492 else
1498 /* Propagate deprecation out to the template. */
1501 {
1507 }
1508 }
1509 \f
1510 /* Walks through the namespace- or function-scope anonymous union
1511 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1512 Returns one of the fields for use in the mangled name. */
1514 static tree
1516 {
1518 tree field;
1520 /* Rather than write the code to handle the non-union case,
1521 just give an error. */
1523 {
1526 }
1531 {
1532 tree decl;
1533 tree ref;
1538 {
1540 "%q#D invalid; an anonymous union can only "
1543 }
1555 else
1560 {
1561 tree base;
1577 }
1580 else
1585 }
1588 }
1590 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1591 anonymous union, then all members must be laid out together. PUBLIC_P
1592 is nonzero if this union is not declared static. */
1594 void
1596 {
1597 tree type;
1598 tree main_decl;
1607 /* The VAR_DECL's context is the same as the TYPE's context. */
1614 {
1617 }
1623 {
1626 }
1629 {
1630 /* Use main_decl to set the mangled name. */
1636 }
1640 }
1641 \f
1642 /* Auxiliary functions to make type signatures for
1643 `operator new' and `operator delete' correspond to
1644 what compiler will be expecting. */
1646 tree
1648 {
1655 {
1658 }
1661 {
1663 {
1664 /* [basic.stc.dynamic.allocation]
1666 The first parameter shall not have an associated default
1667 argument. */
1670 /* Throw away the default argument. */
1672 }
1675 {
1678 }
1679 }
1680 else
1688 {
1691 /* Fall through. */
1693 type = build_exception_variant
1696 /* Fall through. */
1698 }
1700 }
1702 tree
1704 {
1711 {
1714 }
1718 {
1723 ptr_type_node);
1724 }
1726 {
1729 /* Fall through. */
1731 type = build_exception_variant
1734 /* Fall through. */
1736 }
1739 }
1740 \f
1741 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1742 and mark them as needed. */
1744 static void
1746 {
1747 tree fnaddr;
1750 /* It's OK for the vtable to refer to deprecated virtual functions. */
1755 {
1756 tree fn;
1762 /* This entry is an offset: a virtual base class offset, a
1763 virtual call offset, an RTTI offset, etc. */
1768 /* When we don't have vcall offsets, we output thunks whenever
1769 we output the vtables that contain them. With vcall offsets,
1770 we know all the thunks we'll need when we emit a virtual
1771 function, so we emit the thunks there instead. */
1775 }
1776 }
1778 /* Set DECL up to have the closest approximation of "initialized common"
1779 linkage available. */
1781 void
1783 {
1788 /* We can just emit function and compiler-generated variables
1789 statically; having multiple copies is (for the most part) only
1790 a waste of space.
1792 There are two correctness issues, however: the address of a
1793 template instantiation with external linkage should be the
1794 same, independent of what translation unit asks for the
1795 address, and this will not hold when we emit multiple copies of
1796 the function. However, there's little else we can do.
1798 Also, by default, the typeinfo implementation assumes that
1799 there will be only one copy of the string used as the name for
1800 each type. Therefore, if weak symbols are unavailable, the
1801 run-time library should perform a more conservative check; it
1802 should perform a string comparison, rather than an address
1803 comparison. */
1805 else
1806 {
1807 /* Static data member template instantiations, however, cannot
1808 have multiple copies. */
1813 {
1816 }
1818 {
1819 /* We can't do anything useful; leave vars for explicit
1820 instantiation. */
1823 }
1824 }
1827 }
1829 /* For win32 we also want to put explicit instantiations in
1830 linkonce sections, so that they will be merged with implicit
1831 instantiations; otherwise we get duplicate symbol errors.
1832 For Darwin we do not want explicit instantiations to be
1833 linkonce. */
1835 void
1837 {
1838 /* We used to say that this was not necessary on targets that support weak
1839 symbols, because the implicit instantiations will defer to the explicit
1840 one. However, that's not actually the case in SVR4; a strong definition
1841 after a weak one is an error. Also, not making explicit
1842 instantiations one_only means that we can end up with two copies of
1843 some template instantiations. */
1847 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1848 we can get away with not emitting them if they aren't used. We need
1849 to for variables so that cp_finish_decl will update their linkage,
1850 because their DECL_INITIAL may not have been set properly yet. */
1855 {
1859 {
1862 /* Mark it needed so we don't forget to emit it. */
1865 }
1866 }
1867 }
1869 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1870 This predicate will give the right answer during parsing of the
1871 function, which other tests may not. */
1873 bool
1875 {
1877 {
1880 }
1881 /* Unfortunately, import_export_decl has not always been called
1882 before the function is processed, so we cannot simply check
1883 DECL_COMDAT. */
1891 /* A local static in an inline effectively has vague linkage. */
1894 else
1896 }
1898 /* Determine whether or not we want to specifically import or export CTYPE,
1899 using various heuristics. */
1901 static void
1903 {
1904 /* -1 for imported, 1 for exported. */
1907 /* It only makes sense to call this function at EOF. The reason is
1908 that this function looks at whether or not the first non-inline
1909 non-abstract virtual member function has been defined in this
1910 translation unit. But, we can't possibly know that until we've
1911 seen the entire translation unit. */
1917 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1918 we will have CLASSTYPE_INTERFACE_ONLY set but not
1919 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1920 heuristic because someone will supply a #pragma implementation
1921 elsewhere, and deducing it here would produce a conflict. */
1931 /* For a template class, without -fimplicit-templates, check the
1932 repository. If the virtual table is assigned to this
1933 translation unit, then export the class; otherwise, import
1934 it. */
1937 {
1938 /* The ABI specifies that the virtual table and associated
1939 information are emitted with the key method, if any. */
1941 /* If weak symbol support is not available, then we must be
1942 careful not to emit the vtable when the key function is
1943 inline. An inline function can be defined in multiple
1944 translation units. If we were to emit the vtable in each
1945 translation unit containing a definition, we would get
1946 multiple definition errors at link-time. */
1949 }
1951 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1952 a definition anywhere else. */
1956 /* Allow back ends the chance to overrule the decision. */
1961 {
1964 }
1965 }
1967 /* Return true if VAR has already been provided to the back end; in that
1968 case VAR should not be modified further by the front end. */
1969 static bool
1971 {
1973 }
1975 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1976 must be emitted in this translation unit. Mark it as such. */
1978 void
1980 {
1983 {
1984 /* Extern inline functions don't become needed when referenced.
1985 If we know a method will be emitted in other TU and no new
1986 functions can be marked reachable, just use the external
1987 definition. */
1991 /* #pragma interface and -frepo code can call mark_needed for
1992 maybe-in-charge 'tors; mark the clones as well. */
1993 tree clone;
1996 }
1998 {
2000 /* C++ frontend use mark_decl_references to force COMDAT variables
2001 to be output that might appear dead otherwise. */
2003 }
2004 }
2006 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
2007 returns true if a definition of this entity should be provided in
2008 this object file. Callers use this function to determine whether
2009 or not to let the back end know that a definition of DECL is
2010 available in this translation unit. */
2012 bool
2014 {
2016 /* This function should only be called at the end of the translation
2017 unit. We cannot be sure of whether or not something will be
2018 COMDAT until that point. */
2021 /* All entities with external linkage that are not COMDAT/EXTERN should be
2022 emitted; they may be referred to from other object files. */
2025 /* Functions marked "dllexport" must be emitted so that they are
2026 visible to other DLLs. */
2031 /* When not optimizing, do not bother to produce definitions for extern
2032 symbols. */
2041 /* If this entity was used, let the back end see it; it will decide
2042 whether or not to emit it into the object file. */
2045 /* Virtual functions might be needed for devirtualization. */
2050 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
2051 reference to DECL might cause it to be emitted later. */
2053 }
2055 /* If necessary, write out the vtables for the dynamic class CTYPE.
2056 Returns true if any vtables were emitted. */
2058 static bool
2060 {
2061 tree vtbl;
2062 tree primary_vtbl;
2066 /* If the vtables for this class have already been emitted there is
2067 nothing more to do. */
2071 /* Ignore dummy vtables made by get_vtable_decl. */
2075 /* On some targets, we cannot determine the key method until the end
2076 of the translation unit -- which is when this function is
2077 called. */
2081 /* See if any of the vtables are needed. */
2083 {
2087 }
2089 {
2090 /* If the references to this class' vtables are optimized away,
2091 still emit the appropriate debugging information. See
2092 dfs_debug_mark. */
2097 }
2099 /* The ABI requires that we emit all of the vtables if we emit any
2100 of them. */
2102 {
2103 /* Mark entities references from the virtual table as used. */
2107 {
2110 LOOKUP_NORMAL);
2112 /* It had better be all done at compile-time. */
2114 }
2116 /* Write it out. */
2120 /* Because we're only doing syntax-checking, we'll never end up
2121 actually marking the variable as written. */
2125 {
2130 }
2131 }
2133 /* Since we're writing out the vtable here, also write the debug
2134 info. */
2138 }
2140 /* A special return value from type_visibility meaning internal
2141 linkage. */
2145 /* walk_tree helper function for type_visibility. */
2147 static tree
2149 {
2152 {
2154 }
2157 {
2160 }
2165 }
2167 /* Returns the visibility of TYPE, which is the minimum visibility of its
2168 component types. */
2170 static int
2172 {
2176 }
2178 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2179 specified (or if VISIBILITY is static). If TMPL is true, this
2180 constraint is for a template argument, and takes precedence
2181 over explicitly-specified visibility on the template. */
2183 static void
2185 {
2187 {
2188 /* extern "C" declarations aren't affected by the anonymous
2189 namespace. */
2191 {
2197 {
2202 }
2206 }
2207 }
2210 {
2212 /* This visibility was not specified. */
2214 }
2215 }
2217 /* Constrain the visibility of DECL based on the visibility of its template
2218 arguments. */
2220 static void
2222 {
2223 /* If this is a template instantiation, check the innermost
2224 template args for visibility constraints. The outer template
2225 args are covered by the class check. */
2229 {
2235 else
2236 {
2244 {
2247 else
2249 }
2250 }
2253 }
2254 }
2256 /* Like c_determine_visibility, but with additional C++-specific
2257 behavior.
2259 Function-scope entities can rely on the function's visibility because
2260 it is set in start_preparsed_function.
2262 Class-scope entities cannot rely on the class's visibility until the end
2263 of the enclosing class definition.
2265 Note that because namespaces have multiple independent definitions,
2266 namespace visibility is handled elsewhere using the #pragma visibility
2267 machinery rather than by decorating the namespace declaration.
2269 The goal is for constraints from the type to give a diagnostic, and
2270 other constraints to be applied silently. */
2272 void
2274 {
2280 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2282 /* Only relevant for names with external linkage. */
2286 /* Cloned constructors and destructors get the same visibility as
2287 the underlying function. That should be set up in
2288 maybe_clone_body. */
2295 {
2300 else
2302 }
2305 else
2308 /* If DECL is a member of a class, visibility specifiers on the
2309 class can influence the visibility of the DECL. */
2312 else
2313 {
2314 /* Not a class member. */
2316 /* Virtual tables have DECL_CONTEXT set to their associated class,
2317 so they are automatically handled above. */
2322 {
2323 /* Local statics and classes get the visibility of their
2324 containing function by default, except that
2325 -fvisibility-inlines-hidden doesn't affect them. */
2328 {
2332 }
2333 else
2334 {
2338 {
2342 }
2343 else
2344 {
2348 }
2349 }
2351 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2352 but have no TEMPLATE_INFO, so don't try to check it. */
2354 }
2357 {
2358 /* Under -fvisibility-ms-compat, types are visible by default,
2359 even though their contents aren't. */
2366 else
2368 }
2370 {
2371 /* tinfo visibility is based on the type it's for. */
2372 constrain_visibility
2375 /* Give the target a chance to override the visibility associated
2376 with DECL. */
2382 }
2384 /* Template instantiations and specializations get visibility based
2387 {
2390 else
2391 {
2392 /* Set default visibility to whatever the user supplied with
2393 #pragma GCC visibility or a namespace visibility attribute. */
2396 }
2397 }
2398 }
2401 {
2402 /* If the specialization doesn't specify visibility, use the
2403 visibility from the template. */
2411 {
2415 {
2419 else
2420 {
2424 }
2425 }
2428 /* Template argument visibility outweighs #pragma or namespace
2429 visibility, but not an explicit attribute. */
2431 {
2434 {
2435 /* A class template member with explicit visibility
2436 overrides the class visibility, so we need to apply
2437 all the levels of template args directly. */
2440 {
2443 }
2444 }
2446 /* Limit visibility based on its template arguments. */
2448 }
2449 }
2450 }
2456 /* Names in an anonymous namespace get internal linkage.
2457 This might change once we implement export. */
2460 {
2461 /* Propagate anonymity from type to decl. */
2466 }
2468 /* DR 757: A type without linkage shall not be used as the type of a
2469 variable or function with linkage, unless
2470 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2471 o the variable or function is not used (3.2 [basic.def.odr]) or is
2472 defined in the same translation unit.
2474 Since non-extern "C" decls need to be defined in the same
2475 translation unit, we can make the type internal. */
2478 /* If visibility changed and DECL already has DECL_RTL, ensure
2479 symbol flags are updated. */
2486 }
2488 /* By default, static data members and function members receive
2489 the visibility of their containing class. */
2491 static void
2493 {
2499 else
2500 {
2501 /* Default to the class visibility. */
2505 }
2507 /* Give the target a chance to override the visibility associated
2508 with DECL. */
2512 /* Construction virtual tables are not exported because
2513 they cannot be referred to from other object files;
2514 their name is not standardized by the ABI. */
2520 }
2522 /* Returns true iff DECL is an inline that should get hidden visibility
2523 because of -fvisibility-inlines-hidden. */
2525 static bool
2527 {
2529 /* Don't do this for inline templates; specializations might not be
2530 inline, and we don't want them to inherit the hidden
2531 visibility. We'll set it here for all inline instantiations. */
2532 && !processing_template_decl
2537 }
2539 /* Constrain the visibility of a class TYPE based on the visibility of its
2540 field types. Warn if any fields require lesser visibility. */
2542 void
2544 {
2545 tree binfo;
2546 tree t;
2555 /* Don't warn about visibility if the class has explicit visibility. */
2561 {
2566 {
2571 }
2578 }
2582 {
2586 {
2591 }
2597 }
2598 }
2600 /* Functions for adjusting the visibility of a tagged type and its nested
2601 types and declarations when it gets a name for linkage purposes from a
2602 typedef. */
2607 /* First reset the visibility of all the types. */
2609 static void
2611 {
2616 }
2617 static void
2619 {
2621 }
2623 /* Then reset the visibility of any static data members or member
2624 functions that use those types. */
2626 static void
2628 {
2637 }
2638 static void
2640 {
2642 {
2644 {
2649 }
2651 {
2657 }
2662 {
2665 /* Also update its name, for cxx_dwarf_name. */
2667 }
2670 }
2671 }
2672 static void
2674 {
2676 }
2677 void
2679 {
2682 }
2684 /* Set up our initial idea of what the linkage of DECL should be. */
2686 void
2688 {
2690 /* We've already made a decision as to how this function will
2693 {
2696 {
2700 /* A non-template inline function with external linkage will
2701 always be COMDAT. As we must eventually determine the
2702 linkage of all functions, and as that causes writes to
2703 the data mapped in from the PCH file, it's advantageous
2704 to mark the functions at this point. */
2708 {
2709 /* This function must have external linkage, as
2710 otherwise DECL_INTERFACE_KNOWN would have been
2711 set. */
2715 }
2716 }
2719 }
2720 }
2722 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2723 for DECL has not already been determined, do so now by setting
2724 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2725 function is called entities with vague linkage whose definitions
2726 are available must have TREE_PUBLIC set.
2728 If this function decides to place DECL in COMDAT, it will set
2729 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2730 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2731 callers defer that decision until it is clear that DECL is actually
2732 required. */
2734 void
2736 {
2745 /* We cannot determine what linkage to give to an entity with vague
2746 linkage until the end of the file. For example, a virtual table
2747 for a class will be defined if and only if the key method is
2748 defined in this translation unit. As a further example, consider
2749 that when compiling a translation unit that uses PCH file with
2750 "-frepo" it would be incorrect to make decisions about what
2751 entities to emit when building the PCH; those decisions must be
2752 delayed until the repository information has been processed. */
2754 /* Object file linkage for explicit instantiations is handled in
2755 mark_decl_instantiated. For static variables in functions with
2756 vague linkage, maybe_commonize_var is used.
2758 Therefore, the only declarations that should be provided to this
2759 function are those with external linkage that are:
2761 * implicit instantiations of function templates
2763 * inline function
2765 * implicit instantiations of static data members of class
2766 templates
2768 * virtual tables
2770 * typeinfo objects
2772 Furthermore, all entities that reach this point must have a
2773 definition available in this translation unit.
2775 The following assertions check these conditions. */
2777 /* Any code that creates entities with TREE_PUBLIC cleared should
2778 also set DECL_INTERFACE_KNOWN. */
2784 else
2788 /* Check that a definition of DECL is available in this translation
2789 unit. */
2792 /* Assume that DECL will not have COMDAT linkage. */
2794 /* Assume that DECL will not be imported into this translation
2795 unit. */
2798 /* See if the repository tells us whether or not to emit DECL in
2799 this translation unit. */
2804 {
2805 /* The repository indicates that this entity should be defined
2806 here. Make sure the back end honors that request. */
2808 /* Output the definition as an ordinary strong definition. */
2812 }
2815 /* We have already decided what to do with this DECL; there is no
2816 need to check anything further. */
2817 ;
2819 {
2831 /* The ABI requires that all virtual tables be emitted with
2832 COMDAT linkage. However, on systems where COMDAT symbols
2833 don't show up in the table of contents for a static
2834 archive, or on systems without weak symbols (where we
2835 approximate COMDAT linkage by using internal linkage), the
2836 linker will report errors about undefined symbols because
2837 it will not see the virtual table definition. Therefore,
2838 in the case that we know that the virtual table will be
2839 emitted in only one translation unit, we make the virtual
2840 table an ordinary definition with external linkage. */
2843 {
2844 /* CLASS_TYPE is being exported from this translation unit,
2845 so DECL should be defined here. */
2847 /* If a class is declared in a header with the "extern
2848 template" extension, then it will not be instantiated,
2849 even in translation units that would normally require
2850 it. Often such classes are explicitly instantiated in
2851 one translation unit. Therefore, the explicit
2852 instantiation must be made visible to other translation
2853 units. */
2855 else
2856 {
2857 /* The generic C++ ABI says that class data is always
2858 COMDAT, even if there is a key function. Some
2859 variants (e.g., the ARM EABI) says that class data
2860 only has COMDAT linkage if the class data might be
2861 emitted in more than one translation unit. When the
2862 key method can be inline and is inline, we still have
2863 to arrange for comdat even though
2864 class_data_always_comdat is false. */
2868 {
2869 /* The ABI requires COMDAT linkage. Normally, we
2870 only emit COMDAT things when they are needed;
2871 make sure that we realize that this entity is
2872 indeed needed. */
2875 }
2876 }
2877 }
2881 else
2883 }
2885 {
2888 {
2894 /* If -fno-rtti was specified, then we cannot be sure
2895 that RTTI information will be emitted with the
2896 virtual table of the class, so we must emit it
2897 wherever it is used. */
2900 else
2901 {
2904 {
2910 {
2913 }
2914 }
2915 else
2917 }
2918 }
2919 else
2921 }
2923 {
2924 /* DECL is an implicit instantiation of a function or static
2925 data member. */
2928 || (flag_implicit_inline_templates
2932 else
2933 /* If we are not implicitly generating templates, then mark
2934 this entity as undefined in this translation unit. */
2936 }
2938 {
2940 {
2944 {
2948 && ! flag_implement_inlines
2954 /* Always make artificials weak. */
2957 else
2959 }
2960 }
2961 else
2963 }
2964 else
2968 {
2969 /* If we are importing DECL into this translation unit, mark is
2970 an undefined here. */
2973 }
2975 {
2976 /* If we decided to put DECL in COMDAT, mark it accordingly at
2977 this point. */
2979 }
2982 }
2984 /* Return an expression that performs the destruction of DECL, which
2985 must be a VAR_DECL whose type has a non-trivial destructor, or is
2986 an array whose (innermost) elements have a non-trivial destructor. */
2988 tree
2990 {
2994 }
2996 /* Returns the initialization guard variable for the variable DECL,
2997 which has static storage duration. */
2999 tree
3001 {
3002 tree sname;
3003 tree guard;
3008 {
3009 tree guard_type;
3011 /* We use a type that is big enough to contain a mutex as well
3012 as an integer counter. */
3017 /* The guard should have the same linkage as what it guards. */
3035 }
3037 }
3039 /* Return an atomic load of src with the appropriate memory model. */
3041 static tree
3043 {
3058 }
3060 /* Return those bits of the GUARD variable that should be set when the
3061 guarded entity is actually initialized. */
3063 static tree
3065 {
3067 {
3068 /* We only set the first byte of the guard, in order to leave room
3069 for a mutex in the high-order bits. */
3072 guard);
3075 guard);
3077 }
3080 }
3082 /* Return an expression which determines whether or not the GUARD
3083 variable has already been initialized. */
3085 tree
3087 {
3088 tree guard_value;
3092 else
3095 /* Mask off all but the low bit. */
3097 {
3103 tf_warning_or_error);
3104 }
3111 tf_warning_or_error);
3112 }
3114 /* Return an expression which sets the GUARD variable, indicating that
3115 the variable being guarded has been initialized. */
3117 tree
3119 {
3120 tree guard_init;
3122 /* Set the GUARD to one. */
3128 tf_warning_or_error);
3129 }
3131 /* Returns true iff we can tell that VAR does not have a dynamic
3132 initializer. */
3134 static bool
3136 {
3137 /* If it's defined in another TU, we can't tell. */
3140 /* If it has a non-trivial destructor, registering the destructor
3141 counts as dynamic initialization. */
3144 /* If it's in this TU, its initializer has been processed, unless
3145 it's a case of self-initialization, then DECL_INITIALIZED_P is
3146 false while the initializer is handled by finish_id_expression. */
3149 /* If it has no initializer or a constant one, it's not dynamic. */
3152 }
3154 /* Returns true iff VAR is a variable that needs uses to be
3155 wrapped for possible dynamic initialization. */
3157 static bool
3159 {
3165 }
3167 /* Get the FUNCTION_DECL for the shared TLS init function for this
3168 translation unit. */
3170 static tree
3172 {
3176 {
3179 void_list_node));
3185 }
3187 }
3189 /* Get a FUNCTION_DECL for the init function for the thread_local
3190 variable VAR. The init function will be an alias to the function
3191 that initializes all the non-local TLS variables in the translation
3192 unit. The init function is only used by the wrapper function. */
3194 static tree
3196 {
3197 /* Only C++11 TLS vars need this init fn. */
3201 /* If -fno-extern-tls-init, assume that we don't need to call
3202 a tls init function for a variable defined in another TU. */
3206 #ifdef ASM_OUTPUT_DEF
3207 /* If the variable is internal, or if we can't generate aliases,
3208 call the local init function directly. */
3210 #endif
3216 {
3219 void_list_node));
3228 {
3230 /* If the variable is defined somewhere else and might have static
3231 initialization, make the init function a weak reference. */
3237 else
3239 }
3249 }
3251 }
3253 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3254 variable VAR. The wrapper function calls the init function (if any) for
3255 VAR and then returns a reference to VAR. The wrapper function is used
3256 in place of VAR everywhere VAR is mentioned. */
3258 tree
3260 {
3261 /* Only C++11 TLS vars need this wrapper fn. */
3268 {
3269 /* A named rvalue reference is an lvalue, so the wrapper should
3270 always return an lvalue reference. */
3279 /* The wrapper is inline and emitted everywhere var is used. */
3282 {
3284 #ifdef HAVE_GAS_HIDDEN
3285 /* Make the wrapper bind locally; there's no reason to share
3286 the wrapper between multiple shared objects. */
3289 #endif
3290 }
3296 #if 0
3297 /* We want CSE to commonize calls to the wrapper, but marking it as
3298 pure is unsafe since it has side-effects. I guess we need a new
3299 ECF flag even weaker than ECF_PURE. FIXME! */
3301 #endif
3306 }
3308 }
3310 /* At EOF, generate the definition for the TLS wrapper function FN:
3312 T& var_wrapper() {
3313 if (init_fn) init_fn();
3314 return var;
3315 } */
3317 static void
3319 {
3324 /* Only call the init fn if there might be one. */
3326 {
3328 /* If init_fn is a weakref, make sure it exists before calling. */
3330 {
3335 tf_warning_or_error);
3337 }
3341 {
3344 }
3345 }
3346 else
3347 /* If there's no initialization, the wrapper is a constant function. */
3352 }
3354 /* Start the process of running a particular set of global constructors
3355 or destructors. Subroutine of do_[cd]tors. Also called from
3356 vtv_start_verification_constructor_init_function. */
3358 static tree
3360 {
3361 tree body;
3362 tree fndecl;
3365 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3368 {
3371 #ifdef JOINER
3373 #else
3375 #endif
3378 }
3379 else
3385 NULL_TREE));
3390 /* Mark as artificial because it's not explicitly in the user's
3391 source code. */
3394 /* Mark this declaration as used to avoid spurious warnings. */
3397 /* Mark this function as a global constructor or destructor. */
3400 else
3406 }
3408 /* Finish the process of running a particular set of global constructors
3409 or destructors. Subroutine of do_[cd]tors. */
3411 static void
3413 {
3414 tree fn;
3416 /* Finish up. */
3421 {
3424 }
3425 else
3426 {
3429 }
3432 }
3434 /* The names of the parameters to the function created to handle
3435 initializations and destructions for objects with static storage
3436 duration. */
3440 /* The name of the function we create to handle initializations and
3441 destructions for objects with static storage duration. */
3444 /* The declaration for the __INITIALIZE_P argument. */
3447 /* The declaration for the __PRIORITY argument. */
3450 /* The declaration for the static storage duration function. */
3453 /* All the static storage duration functions created in this
3454 translation unit. */
3457 /* A map from priority levels to information about that priority
3458 level. There may be many such levels, so efficient lookup is
3459 important. */
3462 /* Begins the generation of the function that will handle all
3463 initialization and destruction of objects with static storage
3464 duration. The function generated takes two parameters of type
3465 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3466 nonzero, it performs initializations. Otherwise, it performs
3467 destructions. It only performs those initializations or
3468 destructions with the indicated __PRIORITY. The generated function
3469 returns no value.
3471 It is assumed that this function will only be called once per
3472 translation unit. */
3474 static tree
3476 {
3477 tree type;
3478 tree body;
3481 /* Create the identifier for this function. It will be of the form
3482 SSDF_IDENTIFIER_<number>. */
3487 NULL_TREE);
3489 /* Create the FUNCTION_DECL itself. */
3492 type);
3496 /* Put this function in the list of functions to be called from the
3497 static constructors and destructors. */
3499 {
3502 /* Take this opportunity to initialize the map from priority
3503 numbers to information about that priority level. */
3506 /*delete_value_fn=*/
3509 /* We always need to generate functions for the
3510 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3511 priorities later, we'll be sure to find the
3512 DEFAULT_INIT_PRIORITY. */
3514 }
3518 /* Create the argument list. */
3519 initialize_p_decl = cp_build_parm_decl
3523 priority_decl = cp_build_parm_decl
3531 /* Put the function in the global scope. */
3534 /* Start the function itself. This is equivalent to declaring the
3535 function as:
3537 static void __ssdf (int __initialize_p, init __priority_p);
3539 It is static because we only need to call this function from the
3540 various constructor and destructor functions for this module. */
3543 SF_PRE_PARSED);
3545 /* Set up the scope of the outermost block in the function. */
3549 }
3551 /* Finish the generation of the function which performs initialization
3552 and destruction of objects with static storage duration. After
3553 this point, no more such objects can be created. */
3555 static void
3557 {
3558 /* Close out the function. */
3561 }
3563 /* Return the information about the indicated PRIORITY level. If no
3564 code to handle this level has yet been generated, generate the
3565 appropriate prologue. */
3567 static priority_info
3569 {
3570 priority_info pi;
3571 splay_tree_node n;
3576 {
3577 /* Create a new priority information structure, and insert it
3578 into the map. */
3585 }
3586 else
3590 }
3592 /* The effective initialization priority of a DECL. */
3594 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3595 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3596 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3598 /* Whether a DECL needs a guard to protect it against multiple
3599 initialization. */
3601 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3602 || DECL_ONE_ONLY (decl) \
3603 || DECL_WEAK (decl)))
3605 /* Called from one_static_initialization_or_destruction(),
3606 via walk_tree.
3607 Walks the initializer list of a global variable and looks for
3608 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3609 and that have their DECL_CONTEXT() == NULL.
3610 For each such temporary variable, set their DECL_CONTEXT() to
3611 the current function. This is necessary because otherwise
3612 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3613 when trying to refer to a temporary variable that does not have
3614 it's DECL_CONTECT() properly set. */
3615 static tree
3619 {
3623 {
3624 tree var;
3632 }
3635 }
3637 /* Set up to handle the initialization or destruction of DECL. If
3638 INITP is nonzero, we are initializing the variable. Otherwise, we
3639 are destroying it. */
3641 static void
3643 {
3645 tree guard;
3647 /* If we are supposed to destruct and there's a trivial destructor,
3648 nothing has to be done. */
3653 /* Trick the compiler into thinking we are at the file and line
3654 where DECL was declared so that error-messages make sense, and so
3655 that the debugger will show somewhat sensible file and line
3656 information. */
3659 /* Make sure temporary variables in the initialiser all have
3660 their DECL_CONTEXT() set to a value different from NULL_TREE.
3661 This can happen when global variables initialisers are built.
3662 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3663 the temporary variables that might have been generated in the
3664 accompagning initialisers is NULL_TREE, meaning the variables have been
3665 declared in the global namespace.
3666 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3667 of the temporaries are set to the current function decl. */
3669 fix_temporary_vars_context_r,
3670 NULL);
3672 /* Because of:
3674 [class.access.spec]
3676 Access control for implicit calls to the constructors,
3677 the conversion functions, or the destructor called to
3678 create and destroy a static data member is performed as
3679 if these calls appeared in the scope of the member's
3680 class.
3682 we pretend we are in a static member function of the class of
3683 which the DECL is a member. */
3685 {
3688 }
3690 /* Assume we don't need a guard. */
3692 /* We need a guard if this is an object with external linkage that
3693 might be initialized in more than one place. (For example, a
3694 static data member of a template, when the data member requires
3695 construction.) */
3697 {
3698 tree guard_cond;
3702 /* When using __cxa_atexit, we just check the GUARD as we would
3703 for a local static. */
3705 {
3706 /* When using __cxa_atexit, we never try to destroy
3707 anything from a static destructor. */
3710 }
3711 /* If we don't have __cxa_atexit, then we will be running
3712 destructors from .fini sections, or their equivalents. So,
3713 we need to know how many times we've tried to initialize this
3714 object. We do initializations only if the GUARD is zero,
3715 i.e., if we are the first to initialize the variable. We do
3716 destructions only if the GUARD is one, i.e., if we are the
3717 last to destroy the variable. */
3719 guard_cond
3721 EQ_EXPR,
3723 guard,
3725 tf_warning_or_error),
3726 integer_one_node,
3727 tf_warning_or_error);
3728 else
3729 guard_cond
3731 EQ_EXPR,
3733 guard,
3735 tf_warning_or_error),
3736 integer_zero_node,
3737 tf_warning_or_error);
3741 }
3744 /* If we're using __cxa_atexit, we have not already set the GUARD,
3745 so we must do so now. */
3749 /* Perform the initialization or destruction. */
3751 {
3753 {
3756 {
3760 }
3761 }
3763 /* If we're using __cxa_atexit, register a function that calls the
3764 destructor for the object. */
3767 }
3768 else
3771 /* Finish the guard if-stmt, if necessary. */
3773 {
3776 }
3778 /* Now that we're done with DECL we don't need to pretend to be a
3779 member of its class any longer. */
3782 }
3784 /* Generate code to do the initialization or destruction of the decls in VARS,
3785 a TREE_LIST of VAR_DECL with static storage duration.
3786 Whether initialization or destruction is performed is specified by INITP. */
3788 static void
3790 {
3793 /* Build the outer if-stmt to check for initialization or destruction. */
3797 EQ_EXPR,
3798 initialize_p_decl,
3799 cond,
3800 tf_warning_or_error);
3803 /* To make sure dynamic construction doesn't access globals from other
3804 compilation units where they might not be yet constructed, for
3805 -fsanitize=address insert __asan_before_dynamic_init call that
3806 prevents access to either all global variables that need construction
3807 in other compilation units, or at least those that haven't been
3808 initialized yet. Variables that need dynamic construction in
3809 the current compilation unit are kept accessible. */
3816 tree priority_if_stmt;
3818 priority_info pi;
3820 /* If we don't need a destructor, there's nothing to do. Avoid
3821 creating a possibly empty if-stmt. */
3823 {
3826 }
3828 /* Remember that we had an initialization or finalization at this
3829 priority. */
3834 else
3837 /* Conditionalize this initialization on being in the right priority
3838 and being initializing/finalizing appropriately. */
3841 EQ_EXPR,
3842 priority_decl,
3844 tf_warning_or_error);
3847 /* Process initializers with same priority. */
3851 /* Do one initialization or destruction. */
3855 /* Finish up the priority if-stmt body. */
3861 /* Revert what __asan_before_dynamic_init did by calling
3862 __asan_after_dynamic_init. */
3866 /* Finish up the init/destruct if-stmt body. */
3869 }
3871 /* VARS is a list of variables with static storage duration which may
3872 need initialization and/or finalization. Remove those variables
3873 that don't really need to be initialized or finalized, and return
3874 the resulting list. The order in which the variables appear in
3875 VARS is in reverse order of the order in which they should actually
3876 be initialized. The list we return is in the unreversed order;
3877 i.e., the first variable should be initialized first. */
3879 static tree
3881 {
3886 {
3891 /* Deal gracefully with error. */
3893 {
3896 }
3898 /* The only things that can be initialized are variables. */
3901 /* If this object is not defined, we don't need to do anything
3902 here. */
3904 {
3907 }
3909 /* Also, if the initializer already contains errors, we can bail
3910 out now. */
3913 {
3916 }
3918 /* This variable is going to need initialization and/or
3919 finalization, so we add it to the list. */
3923 }
3926 }
3928 /* Make sure we have told the back end about all the variables in
3929 VARS. */
3931 static void
3933 {
3934 tree v;
3937 {
3940 {
3943 }
3944 }
3945 }
3947 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
3948 (otherwise) that will initialize all global objects with static
3949 storage duration having the indicated PRIORITY. */
3951 static void
3954 {
3956 tree fndecl;
3957 tree body;
3961 /* ??? */
3962 /* Was: locus->line++; */
3964 /* We use `I' to indicate initialization and `D' to indicate
3965 destruction. */
3968 /* We emit the function lazily, to avoid generating empty
3969 global constructors and destructors. */
3972 /* For Objective-C++, we may need to initialize metadata found in this module.
3973 This must be done _before_ any other static initializations. */
3976 {
3979 }
3981 /* Call the static storage duration function with appropriate
3982 arguments. */
3984 {
3985 /* Calls to pure or const functions will expand to nothing. */
3987 {
3988 tree call;
3995 constructor_p),
3997 priority),
3998 NULL_TREE);
4000 }
4001 }
4003 /* Close out the function. */
4006 }
4008 /* Generate constructor and destructor functions for the priority
4009 indicated by N. */
4011 static int
4013 {
4018 /* Generate the functions themselves, but only if they are really
4019 needed. */
4025 /* Keep iterating. */
4027 }
4029 /* Java requires that we be able to reference a local address for a
4030 method, and not be confused by PLT entries. If supported, create a
4031 hidden alias for all such methods. */
4033 static void
4035 {
4036 #ifndef HAVE_GAS_HIDDEN
4038 #endif
4042 {
4048 {
4049 /* Mangle the name in a predictable way; we need to reference
4050 this from a java compiled object file. */
4061 }
4062 }
4063 }
4065 /* Return C++ property of T, based on given operation OP. */
4067 static int
4069 {
4071 {
4073 {
4081 }
4098 }
4099 }
4101 /* Collect source file references recursively, starting from NAMESPC. */
4103 static void
4105 {
4106 tree t;
4111 /* Iterate over names in this name space. */
4116 /* Dump siblings, if any */
4119 /* Dump children, if any */
4121 }
4123 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4124 starting from NAMESPC. */
4126 static void
4128 {
4132 /* Collect decls from this namespace */
4135 /* Collect siblings, if any */
4138 /* Collect children, if any */
4140 }
4142 /* Returns true iff there is a definition available for variable or
4143 function DECL. */
4145 static bool
4147 {
4150 else
4151 {
4154 }
4155 }
4157 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4159 [expr.const]
4161 An integral constant-expression can only involve ... const
4162 variables of integral or enumeration types initialized with
4163 constant expressions ...
4165 C++0x also allows constexpr variables and temporaries initialized
4166 with constant expressions. We handle the former here, but the latter
4167 are just folded away in cxx_eval_constant_expression.
4169 The standard does not require that the expression be non-volatile.
4170 G++ implements the proposed correction in DR 457. */
4172 bool
4174 {
4178 /* We don't know if a template static data member is initialized with
4179 a constant expression until we instantiate its initializer. Even
4180 in the case of a constexpr variable, we can't treat it as a
4181 constant until its initializer is complete in case it's used in
4182 its own initializer. */
4185 }
4187 /* Returns true if DECL could be a symbolic constant variable, depending on
4188 its initializer. */
4190 bool
4192 {
4200 }
4202 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4203 called from grokfndecl and grokvardecl; in all modes it is called from
4204 cp_write_global_declarations. */
4206 void
4208 {
4210 /* In C++11 it's ok if the decl is defined. */
4214 /* The type that got us on no_linkage_decls must have gotten a name for
4217 /* The type might end up having a typedef name for linkage purposes. */
4220 {
4228 /* DRs 132, 319 and 389 seem to indicate types with
4229 no linkage can only be used to declare extern "C"
4230 entities. Since it's not always an error in the
4231 ISO C++ 90 Standard, we only issue a warning. */
4233 "with no linkage used to declare variable %q#D with "
4235 else
4238 decl);
4243 }
4245 {
4248 "%q#D, declared using local type "
4250 }
4254 else
4257 }
4259 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4261 static void
4263 {
4265 }
4267 /* Clear DECL_EXTERNAL for NODE. */
4269 static bool
4271 {
4274 }
4276 /* Build up the function to run dynamic initializers for thread_local
4277 variables in this translation unit and alias the init functions for the
4278 individual variables to it. */
4280 static void
4282 {
4292 boolean_type_node);
4307 tf_warning_or_error);
4310 tf_warning_or_error));
4312 {
4317 #ifdef ASM_OUTPUT_DEF
4318 /* Output init aliases even with -fno-extern-tls-init. */
4320 {
4324 cgraph_node *alias
4328 }
4329 #endif
4330 }
4336 }
4338 /* We're at the end of compilation, so generate any mangling aliases that
4339 we've been saving up, if DECL is going to be output and ID2 isn't
4340 already taken by another declaration. */
4342 static void
4344 {
4345 /* If there's a declaration already using this mangled name,
4346 don't create a compatibility alias that conflicts. */
4353 /* Don't create an alias to an unreferenced function. */
4365 else
4367 }
4369 /* Note that we might want to emit an alias with the symbol ID2 for DECL at
4370 the end of translation, for compatibility across bugs in the mangling
4371 implementation. */
4373 void
4375 {
4376 #ifdef ASM_OUTPUT_DEF
4379 else
4380 {
4383 }
4384 #endif
4385 }
4387 static void
4389 {
4391 {
4395 }
4396 }
4398 /* The entire file is now complete. If requested, dump everything
4399 to a file. */
4401 static void
4403 {
4408 {
4411 }
4412 }
4416 /* Check the deallocation functions for CODE to see if we want to warn that
4417 only one was defined. */
4419 static void
4421 {
4427 {
4429 /* We're only interested in usual deallocation functions. */
4434 else
4436 }
4443 }
4445 /* Check the global deallocation functions to see if we want to warn about
4446 defining unsized without sized (or vice versa). */
4448 static void
4450 {
4455 }
4457 /* This routine is called at the end of compilation.
4458 Its job is to create all the code needed to initialize and
4459 destroy the global aggregates. We do the destruction
4460 first, since that way we only need to reverse the decls once. */
4462 void
4464 {
4465 tree vars;
4470 tree decl;
4475 /* Bad parse errors. Just forget about it. */
4480 /* This is the point to write out a PCH if we're doing that.
4481 In that case we do not want to do anything else. */
4483 {
4487 }
4494 /* Handle -fdump-ada-spec[-slim] */
4496 {
4499 else
4503 }
4505 /* FIXME - huh? was input_line -= 1;*/
4507 /* We now have to write out all the stuff we put off writing out.
4508 These include:
4510 o Template specializations that we have not yet instantiated,
4511 but which are needed.
4512 o Initialization and destruction for non-local objects with
4513 static storage duration. (Local objects with static storage
4514 duration are initialized when their scope is first entered,
4515 and are cleaned up via atexit.)
4516 o Virtual function tables.
4518 All of these may cause others to be needed. For example,
4519 instantiating one function may cause another to be needed, and
4520 generating the initializer for an object may cause templates to be
4521 instantiated, etc., etc. */
4525 do
4526 {
4527 tree t;
4528 tree decl;
4532 /* If there are templates that we've put off instantiating, do
4533 them now. */
4537 /* Write out virtual tables as required. Note that writing out
4538 the virtual table for a template class may cause the
4539 instantiation of members of that class. If we write out
4540 vtables then we remove the class from our list so we don't
4541 have to look at it again. */
4545 {
4548 }
4552 {
4556 {
4558 {
4561 }
4562 else
4566 }
4567 }
4569 /* Write out needed type info variables. We have to be careful
4570 looping through unemitted decls, because emit_tinfo_decl may
4571 cause other variables to be needed. New elements will be
4572 appended, and we remove from the vector those that actually
4573 get emitted. */
4577 {
4580 }
4582 /* The list of objects with static storage duration is built up
4583 in reverse order. We clear STATIC_AGGREGATES so that any new
4584 aggregates added during the initialization of these will be
4585 initialized in the correct order when we next come around the
4586 loop. */
4590 {
4591 /* We need to start a new initialization function each time
4592 through the loop. That's because we need to know which
4593 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4594 isn't computed until a function is finished, and written
4595 out. That's a deficiency in the back end. When this is
4596 fixed, these initialization functions could all become
4597 inline, with resulting performance improvements. */
4598 tree ssdf_body;
4600 /* Set the line and file, so that it is obviously not from
4601 the source file. */
4605 /* Make sure the back end knows about all the variables. */
4608 /* First generate code to do all the initializations. */
4612 /* Then, generate code to do all the destructions. Do these
4613 in reverse order so that the most recently constructed
4614 variable is the first destroyed. If we're using
4615 __cxa_atexit, then we don't need to do this; functions
4616 were registered at initialization time to destroy the
4617 local statics. */
4619 {
4622 }
4623 else
4626 /* Finish up the static storage duration function for this
4627 round. */
4631 /* All those initializations and finalizations might cause
4632 us to need more inline functions, more template
4633 instantiations, etc. */
4635 ssdf_count++;
4636 /* ??? was: locus_at_end_of_parsing.line++; */
4637 }
4639 /* Now do the same for thread_local variables. */
4642 /* Go through the set of inline functions whose bodies have not
4643 been emitted yet. If out-of-line copies of these functions
4644 are required, emit them. */
4646 {
4647 /* Does it need synthesizing? */
4650 {
4651 /* Even though we're already at the top-level, we push
4652 there again. That way, when we pop back a few lines
4653 hence, all of our state is restored. Otherwise,
4654 finish_function doesn't clean things up, and we end
4655 up with CURRENT_FUNCTION_DECL set. */
4657 /* The decl's location will mark where it was first
4658 needed. Save that so synthesize method can indicate
4659 where it was needed from, in case of error */
4664 }
4672 /* We lie to the back end, pretending that some functions
4673 are not defined when they really are. This keeps these
4674 functions from being put out unnecessarily. But, we must
4675 stop lying when the functions are referenced, or if they
4676 are not comdat since they need to be put out now. If
4677 DECL_INTERFACE_KNOWN, then we have already set
4678 DECL_EXTERNAL appropriately, so there's no need to check
4679 again, and we do not want to clear DECL_EXTERNAL if a
4680 previous call to import_export_decl set it.
4682 This is done in a separate for cycle, because if some
4683 deferred function is contained in another deferred
4684 function later in deferred_fns varray,
4685 rest_of_compilation would skip this function and we
4686 really cannot expand the same function twice. */
4691 {
4700 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4701 group, we need to mark all symbols in the same comdat group
4702 that way. */
4709 }
4711 /* If we're going to need to write this function out, and
4712 there's already a body for it, create RTL for it now.
4713 (There might be no body if this is a method we haven't
4714 gotten around to synthesizing yet.) */
4719 {
4720 /* We will output the function; no longer consider it in this
4721 loop. */
4723 /* Generate RTL for this function now that we know we
4724 need it. */
4726 /* If we're compiling -fsyntax-only pretend that this
4727 function has been written out so that we don't try to
4728 expand it again. */
4732 }
4733 }
4738 /* Static data members are just like namespace-scope globals. */
4740 {
4742 /* Don't write it out if we haven't seen a definition. */
4746 /* If this static data member is needed, provide it to the
4747 back end. */
4750 }
4756 retries++;
4757 }
4762 /* All used inline functions must have a definition at this point. */
4764 {
4767 /* If the definition actually was available here, then the
4768 fact that the function was not defined merely represents
4769 that for some reason (use of a template repository,
4770 #pragma interface, etc.) we decided not to emit the
4771 definition here. */
4773 /* Don't complain if the template was defined. */
4777 {
4780 /* Avoid a duplicate warning from check_global_declaration. */
4782 }
4783 }
4785 /* So must decls that use a type with no linkage. */
4791 /* Then, do the Objective-C stuff. This is where all the
4792 Objective-C module stuff gets generated (symtab,
4793 class/protocol/selector lists etc). This must be done after C++
4794 templates, destructors etc. so that selectors used in C++
4795 templates are properly allocated. */
4799 /* We give C linkage to static constructors and destructors. */
4802 /* Generate initialization and destruction functions for all
4803 priorities for which they are required. */
4806 generate_ctor_and_dtor_functions_for_priority,
4809 /* If this is obj-c++ and we need a static init, call
4810 generate_ctor_or_dtor_function. */
4812 DEFAULT_INIT_PRIORITY,
4815 /* We're done with the splay-tree now. */
4819 /* Generate any missing aliases. */
4822 /* We're done with static constructors, so we can go back to "C++"
4823 linkage now. */
4826 /* Generate Java hidden aliases. */
4830 {
4834 }
4840 /* The entire file is now complete. If requested, dump everything
4841 to a file. */
4845 {
4848 }
4853 /* Indicate that we're done with front end processing. */
4855 }
4857 /* Perform any post compilation-proper cleanups for the C++ front-end.
4858 This should really go away. No front-end should need to do
4859 anything past the compilation process. */
4861 void
4863 {
4867 {
4868 /* Generate the special constructor initialization function that
4869 calls __VLTRegisterPairs, and give it a very high
4870 initialization priority. This must be done after
4871 finalize_compilation_unit so that we have accurate
4872 information about which vtable will actually be emitted. */
4874 }
4878 #ifdef ENABLE_CHECKING
4883 }
4885 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
4886 function to call in parse-tree form; it has not yet been
4887 semantically analyzed. ARGS are the arguments to the function.
4888 They have already been semantically analyzed. This may change
4889 ARGS. */
4891 tree
4893 tsubst_flags_t complain)
4894 {
4895 tree orig_fn;
4897 tree expr;
4898 tree object;
4904 {
4913 /* Transform the arguments and add the implicit "this"
4914 parameter. That must be done before the FN is transformed
4915 because we depend on the form of FN. */
4919 {
4923 }
4924 /* Now that the arguments are done, transform FN. */
4926 }
4928 /* A qualified name corresponding to a bound pointer-to-member is
4929 represented as an OFFSET_REF:
4931 struct B { void g(); };
4932 void (B::*p)();
4933 void B::g() { (this->*p)(); } */
4935 {
4939 complain);
4941 }
4945 else
4954 }
4957 void
4959 {
4964 {
4968 {
4971 }
4972 }
4973 }
4975 /* Return true if function DECL can be inlined. This is used to force
4976 instantiation of methods that might be interesting for inlining. */
4977 bool
4979 {
4985 /* When optimizing, we might inline everything when flatten
4986 attribute or heuristics inlining for size or autoinlining
4987 is used. */
4989 }
4991 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
4992 If DECL is a specialization or implicitly declared class member,
4993 generate the actual definition. Return false if something goes
4994 wrong, true otherwise. */
4996 bool
4998 {
4999 /* If DECL is a BASELINK for a single function, then treat it just
5000 like the DECL for the function. Otherwise, if the BASELINK is
5001 for an overloaded function, we don't know which function was
5002 actually used until after overload resolution. */
5004 {
5009 }
5011 /* Set TREE_USED for the benefit of -Wunused. */
5016 /* Mark enumeration types as used. */
5025 {
5027 {
5030 {
5031 /* We mark a lambda conversion op as deleted if we can't
5032 generate it properly; see maybe_add_lambda_conv_op. */
5036 }
5037 }
5039 {
5043 }
5045 }
5051 /* We can only check DECL_ODR_USED on variables or functions with
5052 DECL_LANG_SPECIFIC set, and these are also the only decls that we
5053 might need special handling for. */
5057 {
5059 {
5063 }
5065 }
5067 /* We only want to do this processing once. We don't need to keep trying
5068 to instantiate inline templates, because unit-at-a-time will make sure
5069 we get them compiled before functions that want to inline them. */
5073 /* If within finish_function, defer the rest until that function
5074 finishes, otherwise it might recurse. */
5076 {
5079 }
5081 /* Normally, we can wait until instantiation-time to synthesize DECL.
5082 However, if DECL is a static data member initialized with a constant
5083 or a constexpr function, we need it right now because a reference to
5084 such a data member or a call to such function is not value-dependent.
5085 For a function that uses auto in the return type, we need to instantiate
5086 it to find out its type. For OpenMP user defined reductions, we need
5087 them instantiated for reduction clauses which inline them by hand
5088 directly. */
5097 {
5098 /* Instantiating a function will result in garbage collection. We
5099 must treat this situation as if we were within the body of a
5100 function so as to avoid collecting live data only referenced from
5101 the stack (such as overload resolution candidates). */
5106 }
5111 /* Check this too in case we're within instantiate_non_dependent_expr. */
5117 {
5121 }
5123 /* If we don't need a value, then we don't need to synthesize DECL. */
5131 /* DR 757: A type without linkage shall not be used as the type of a
5132 variable or function with linkage, unless
5133 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5134 o the variable or function is not used (3.2 [basic.def.odr]) or is
5135 defined in the same translation unit. */
5142 {
5144 /* There's no way to define a local extern, and adding it to
5145 the vector interferes with GC, so give an error now. */
5147 else
5149 }
5153 /* Remember it, so we can check it was defined. */
5156 /* Is it a synthesized method that needs to be synthesized? */
5160 /* A function defaulted outside the class is synthesized either by
5161 cp_finish_decl or instantiate_decl. */
5164 {
5165 /* Defer virtual destructors so that thunks get the right
5166 linkage. */
5168 {
5171 }
5173 /* Remember the current location for a function we will end up
5174 synthesizing. Then we can inform the user where it was
5175 required in the case of error. */
5178 /* Synthesizing an implicitly defined member function will result in
5179 garbage collection. We must treat this situation as if we were
5180 within the body of a function so as to avoid collecting live data
5181 on the stack (such as overload resolution candidates).
5183 We could just let cp_write_global_declarations handle synthesizing
5184 this function by adding it to deferred_fns, but doing
5185 it at the use site produces better error messages. */
5189 /* If this is a synthesized method we don't need to
5190 do the instantiation test below. */
5191 }
5197 /* If this is a function or variable that is an instance of some
5198 template, we now know that we will need to actually do the
5199 instantiation. We check that DECL is not an explicit
5200 instantiation because that is not checked in instantiate_decl.
5202 We put off instantiating functions in order to improve compile
5203 times. Maintaining a stack of active functions is expensive,
5204 and the inliner knows to instantiate any functions it might
5205 need. Therefore, we always try to defer instantiation. */
5206 {
5211 }
5214 }
5216 bool
5218 {
5220 }
5222 tree
5224 {
5226 }
5228 tree
5230 {
5231 tree fn;
5239 }