diff --git a/Makeconfig b/Makeconfig
index c4dd9ea8f2..c48fcc59e8 100644
--- a/Makeconfig
+++ b/Makeconfig
@@ -857,7 +857,7 @@ host-test-program-cmd = $(host-built-program-cmd)
 endif
 
 # Extra flags to pass to GCC.
-gccwarn := -Wall -Wwrite-strings -Wundef
++gccwarn := -Wall -Wwrite-strings -Wundef
 ifeq ($(enable-werror),yes)
 +gccwarn += -Werror
 endif