diff --git a/cc/util.go b/cc/util.go
index fb6338a..7b8ad18 100644
--- a/cc/util.go
+++ b/cc/util.go
@@ -79,7 +79,8 @@
 
 		systemIncludeFlags: strings.Join(in.SystemIncludeFlags, " "),
 
-		groupStaticLibs: in.GroupStaticLibs,
+		assemblerWithCpp: in.AssemblerWithCpp,
+		groupStaticLibs:  in.GroupStaticLibs,
 
 		proto:            in.proto,
 		protoC:           in.protoC,