diff --git a/llvm/utils/gn/build/BUILD.gn b/llvm/utils/gn/build/BUILD.gn
--- a/llvm/utils/gn/build/BUILD.gn
+++ b/llvm/utils/gn/build/BUILD.gn
@@ -10,6 +10,7 @@
     defines += [ "NDEBUG" ]
   }
 
+  asmflags = target_flags
   cflags = target_flags
   ldflags = target_flags + target_ldflags