Revert r180263. It's causing failures.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180583 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 6 insertions, 18 deletions

diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index a431c5317e..cb375eb4e2 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -476,13 +476,6 @@ template <typename T> static bool isInExternCContext(T *D) {
   return First->getDeclContext()->isExternCContext();
 }
 
-static bool isSingleLineExternC(const Decl &D) {
-  if (const LinkageSpecDecl *SD = dyn_cast<LinkageSpecDecl>(D.getDeclContext()))
-    if (SD->getLanguage() == LinkageSpecDecl::lang_c && !SD->hasBraces())
-      return true;
-  return false;
-}
-
 static LinkageInfo getLVForNamespaceScopeDecl(const NamedDecl *D,
                                               LVComputationKind computation) {
   assert(D->getDeclContext()->getRedeclContext()->isFileContext() &&
@@ -511,8 +504,7 @@ static LinkageInfo getLVForNamespaceScopeDecl(const NamedDecl *D,
         return PrevVar->getLinkageAndVisibility();
 
       if (Var->getStorageClass() != SC_Extern &&
-          Var->getStorageClass() != SC_PrivateExtern &&
-          !isSingleLineExternC(*Var))
+          Var->getStorageClass() != SC_PrivateExtern)
         return LinkageInfo::internal();
     }
 
@@ -1588,8 +1580,11 @@ VarDecl::DefinitionKind VarDecl::isThisDeclarationADefinition(
   //   A declaration directly contained in a linkage-specification is treated
   //   as if it contains the extern specifier for the purpose of determining
   //   the linkage of the declared name and whether it is a definition.
-  if (isSingleLineExternC(*this))
-    return DeclarationOnly;
+  const DeclContext *DC = getDeclContext();
+  if (const LinkageSpecDecl *SD = dyn_cast<LinkageSpecDecl>(DC)) {
+    if (SD->getLanguage() == LinkageSpecDecl::lang_c && !SD->hasBraces())
+      return DeclarationOnly;
+  }
 
   // C99 6.9.2p2:
   //   A declaration of an object that has file scope without an initializer,
diff --git a/test/SemaCXX/undefined-internal.cpp b/test/SemaCXX/undefined-internal.cpp
index 1b76a86dcb..839fdafb34 100644
--- a/test/SemaCXX/undefined-internal.cpp
+++ b/test/SemaCXX/undefined-internal.cpp
@@ -323,10 +323,3 @@ namespace test13 {
   }
 }
 
-namespace test14 {
-  extern "C" const int foo;
-
-  int f() {
-    return foo;
-  }
-}