diff --git a/lib/Object/ArchiveWriter.cpp b/lib/Object/ArchiveWriter.cpp
index e5d6267908d3..11cd72fa69d4 100644
--- a/lib/Object/ArchiveWriter.cpp
+++ b/lib/Object/ArchiveWriter.cpp
@@ -129,9 +129,7 @@ static bool isBSDLike(object::Archive::Kind Kind) {
   case object::Archive::K_BSD:
   case object::Archive::K_DARWIN:
     return true;
-  case object::Archive::K_MIPS64:
-  case object::Archive::K_DARWIN64:
-  case object::Archive::K_COFF:
+  default:
     llvm_unreachable("not supported for writting");
   }
 }