Don't look outside the innermost enclosing namespace when
performing unqualified lookup for a friend class declaration.
rdar://13393749
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177473 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index b3edc5e..1cffce0 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -9467,6 +9467,8 @@
// shouldn't be diagnosing.
LookupName(Previous, S);
+ // When declaring or defining a tag, ignore ambiguities introduced
+ // by types using'ed into this scope.
if (Previous.isAmbiguous() &&
(TUK == TUK_Definition || TUK == TUK_Declaration)) {
LookupResult::Filter F = Previous.makeFilter();
@@ -9477,6 +9479,27 @@
}
F.done();
}
+
+ // C++11 [namespace.memdef]p3:
+ // If the name in a friend declaration is neither qualified nor
+ // a template-id and the declaration is a function or an
+ // elaborated-type-specifier, the lookup to determine whether
+ // the entity has been previously declared shall not consider
+ // any scopes outside the innermost enclosing namespace.
+ //
+ // Does it matter that this should be by scope instead of by
+ // semantic context?
+ if (!Previous.empty() && TUK == TUK_Friend) {
+ DeclContext *EnclosingNS = SearchDC->getEnclosingNamespaceContext();
+ LookupResult::Filter F = Previous.makeFilter();
+ while (F.hasNext()) {
+ NamedDecl *ND = F.next();
+ DeclContext *DC = ND->getDeclContext()->getRedeclContext();
+ if (DC->isFileContext() && !EnclosingNS->Encloses(ND->getDeclContext()))
+ F.erase();
+ }
+ F.done();
+ }
// Note: there used to be some attempt at recovery here.
if (Previous.isAmbiguous())