diff --git a/dl/BUILD.gn b/dl/BUILD.gn
index 8e63bd7..56c1e6d 100644
--- a/dl/BUILD.gn
+++ b/dl/BUILD.gn
@@ -197,7 +197,7 @@
 
     if (!arm_use_neon) {
       configs -= [ "//build/config/compiler:compiler_arm_fpu" ]
-      cflags += [ "-mfpu=neon" ]
+      cflags = [ "-mfpu=neon" ]
     }
 
     sources = [