Compare namespaces properly when looking for redeclarations of

namespace aliases. Fixes PR6341.

llvm-svn: 99664

2 files changed, 12 insertions, 2 deletions

diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 1b4710e3d08..b5dc7305228 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -3736,8 +3736,10 @@ Sema::DeclPtrTy Sema::ActOnNamespaceAliasDef(Scope *S,
     if (NamespaceAliasDecl *AD = dyn_cast<NamespaceAliasDecl>(PrevDecl)) {
       // We already have an alias with the same name that points to the same
       // namespace, so don't create a new one.
+      // FIXME: At some point, we'll want to create the (redundant)
+      // declaration to maintain better source information.
       if (!R.isAmbiguous() && !R.empty() &&
-          AD->getNamespace() == getNamespaceDecl(R.getFoundDecl()))
+          AD->getNamespace()->Equals(getNamespaceDecl(R.getFoundDecl())))
         return DeclPtrTy();
     }
 
diff --git a/clang/test/SemaCXX/namespace-alias.cpp b/clang/test/SemaCXX/namespace-alias.cpp
index 06114c34cc4..3ea1ccfd9f7 100644
--- a/clang/test/SemaCXX/namespace-alias.cpp
+++ b/clang/test/SemaCXX/namespace-alias.cpp
@@ -1,6 +1,6 @@
 // RUN: %clang_cc1 -fsyntax-only -verify %s
 
-namespace N { };
+namespace N { struct X { }; };
 
 namespace A = N;
 
@@ -83,3 +83,11 @@ namespace K {
     KC::func(); // expected-error {{undeclared identifier 'KC'}}
   }
 }
+
+// PR6341
+namespace A = N;
+namespace N { }
+namespace A = N;
+
+A::X nx;
+