diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index ab4a17a..1c6bbed 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -7565,6 +7565,7 @@
     }
   } else if (VDecl->isFileVarDecl()) {
     if (VDecl->getStorageClassAsWritten() == SC_Extern &&
+        !VDecl->isExternC() &&
         (!getLangOpts().CPlusPlus ||
          !Context.getBaseElementType(VDecl->getType()).isConstQualified()))
       Diag(VDecl->getLocation(), diag::warn_extern_init);