diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index ebfb9810d660..5c1de6aeb880 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -1456,7 +1456,8 @@ void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) {
   }
 
   if (New->hasExternalStorage() &&
-      Old->getLinkage() == InternalLinkage)
+      Old->getLinkage() == InternalLinkage &&
+      New->getDeclContext() == Old->getDeclContext())
     New->setStorageClass(Old->getStorageClass());
 
   // Keep a chain of previous declarations.
diff --git a/clang/test/Sema/extern-redecl.c b/clang/test/Sema/extern-redecl.c
new file mode 100644
index 000000000000..067e3c21e4c4
--- /dev/null
+++ b/clang/test/Sema/extern-redecl.c
@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -fsyntax-only %s
+
+// rdar: // 8125274
+static int a16[];  // expected-warning {{tentative array definition assumed to have one element}}
+
+void f16(void) {
+    extern int a16[];
+}
+