Implement support for anonymous structs and unions in C. Both C and
C++ handle anonymous structs/unions in the same way. Addresses several
bugs:
<rdar://problem/6259534>
<rdar://problem/6481130>
<rdar://problem/6483159>
The test case in PR clang/1750 now passes with -fsyntax-only, but
CodeGen for inline assembler still fails.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@62112 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index f3f0a08..6aeda8b 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -861,7 +861,20 @@
/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with
/// no declarator (e.g. "struct foo;") is parsed.
Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) {
- // FIXME: Isn't that more of a parser diagnostic than a sema diagnostic?
+ TagDecl *Tag
+ = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep()));
+ if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) {
+ if (!Record->getDeclName() && Record->isDefinition() &&
+ DS.getStorageClassSpec() != DeclSpec::SCS_typedef)
+ return BuildAnonymousStructOrUnion(S, DS, Record);
+
+ // Microsoft allows unnamed struct/union fields. Don't complain
+ // about them.
+ // FIXME: Should we support Microsoft's extensions in this area?
+ if (Record->getDeclName() && getLangOptions().Microsoft)
+ return Tag;
+ }
+
if (!DS.isMissingDeclaratorOk()) {
// FIXME: This diagnostic is emitted even when various previous
// errors occurred (see e.g. test/Sema/decl-invalid.c). However,
@@ -872,14 +885,6 @@
return 0;
}
- TagDecl *Tag
- = dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep()));
- if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) {
- if (!Record->getDeclName() && Record->isDefinition() &&
- !Record->isInvalidDecl())
- return BuildAnonymousStructOrUnion(S, DS, Record);
- }
-
return Tag;
}
@@ -1031,10 +1036,16 @@
}
} else {
// FIXME: Check GNU C semantics
+ if (Record->isUnion() && !Owner->isRecord()) {
+ Diag(Record->getLocation(), diag::err_anonymous_union_not_member)
+ << (int)getLangOptions().CPlusPlus;
+ Invalid = true;
+ }
}
if (!Record->isUnion() && !Owner->isRecord()) {
- Diag(Record->getLocation(), diag::err_anonymous_struct_not_member);
+ Diag(Record->getLocation(), diag::err_anonymous_struct_not_member)
+ << (int)getLangOptions().CPlusPlus;
Invalid = true;
}
@@ -1084,7 +1095,8 @@
// Inject the members of the anonymous struct/union into the owning
// context and into the identifier resolver chain for name lookup
// purposes.
- Invalid = Invalid || InjectAnonymousStructOrUnionMembers(S, Owner, Record);
+ if (InjectAnonymousStructOrUnionMembers(S, Owner, Record))
+ Invalid = true;
// Mark this as an anonymous struct/union type. Note that we do not
// do this until after we have already checked and injected the
@@ -2890,6 +2902,7 @@
case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break;
}
+ DeclContext *SearchDC = CurContext;
DeclContext *DC = CurContext;
DeclContext *LexicalContext = CurContext;
ScopedDecl *PrevDecl = 0;
@@ -2924,8 +2937,8 @@
// with C structs, unions, and enums when looking for a matching
// tag declaration or definition. See the similar lookup tweak
// in Sema::LookupDecl; is there a better way to deal with this?
- while (isa<RecordDecl>(DC) || isa<EnumDecl>(DC))
- DC = DC->getParent();
+ while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
+ SearchDC = SearchDC->getParent();
}
}
@@ -2943,7 +2956,7 @@
// If this is a use of a previous tag, or if the tag is already declared
// in the same scope (so that the definition/declaration completes or
// rementions the tag), reuse the decl.
- if (TK == TK_Reference || isDeclInScope(PrevDecl, DC, S)) {
+ if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) {
// Make sure that this wasn't declared as an enum and now used as a
// struct or something similar.
if (PrevTagDecl->getTagKind() != Kind) {
@@ -2991,7 +3004,7 @@
// PrevDecl. If it's NULL, we have a new definition.
} else {
// PrevDecl is a namespace.
- if (isDeclInScope(PrevDecl, DC, S)) {
+ if (isDeclInScope(PrevDecl, SearchDC, S)) {
// The tag name clashes with a namespace name, issue an error and
// recover by making this tag be anonymous.
Diag(NameLoc, diag::err_redefinition_different_kind) << Name;
@@ -3024,6 +3037,8 @@
// C structs and unions.
// Find the context where we'll be declaring the tag.
+ // FIXME: We would like to maintain the current DeclContext as the
+ // lexical context,
while (DC->isRecord())
DC = DC->getParent();
LexicalContext = DC;
@@ -3110,11 +3125,7 @@
CurContext = OldContext;
} else
PushOnScopeChains(New, S);
- } else if (getLangOptions().CPlusPlus) {
- // FIXME: We also want to do this for C, but if this tag is
- // defined within a structure CurContext will point to the context
- // enclosing the structure, and we would end up inserting the tag
- // type into the wrong place.
+ } else {
LexicalContext->addDecl(Context, New);
}