PR18234: Mark a tag definition as invalid early if it appears in a
type-specifier in C++. Some checks will assert in this case otherwise (in
particular, the access specifier may be missing if this happens inside a class
definition, due to a violation of an AST invariant).
llvm-svn: 198721
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 07a551d..7cdf81a 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -10396,6 +10396,9 @@
/// former case, Name will be non-null. In the later case, Name will be null.
/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a
/// reference/declaration/definition of a tag.
+///
+/// IsTypeSpecifier is true if this is a type-specifier (or
+/// trailing-type-specifier) other than one in an alias-declaration.
Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
SourceLocation KWLoc, CXXScopeSpec &SS,
IdentifierInfo *Name, SourceLocation NameLoc,
@@ -10405,7 +10408,8 @@
bool &OwnedDecl, bool &IsDependent,
SourceLocation ScopedEnumKWLoc,
bool ScopedEnumUsesClassTag,
- TypeResult UnderlyingType) {
+ TypeResult UnderlyingType,
+ bool IsTypeSpecifier) {
// If this is not a definition, it must have a name.
IdentifierInfo *OrigName = Name;
assert((Name != 0 || TUK == TUK_Definition) &&
@@ -11016,6 +11020,14 @@
cast_or_null<RecordDecl>(PrevDecl));
}
+ // C++11 [dcl.type]p3:
+ // A type-specifier-seq shall not define a class or enumeration [...].
+ if (getLangOpts().CPlusPlus && IsTypeSpecifier && TUK == TUK_Definition) {
+ Diag(New->getLocation(), diag::err_type_defined_in_type_specifier)
+ << Context.getTagDeclType(New);
+ Invalid = true;
+ }
+
// Maybe add qualifier info.
if (SS.isNotEmpty()) {
if (SS.isSet()) {