diff --git a/Makefile b/Makefile
index 1ef92d705984..08a01add09a6 100644
--- a/Makefile
+++ b/Makefile
@@ -412,7 +412,7 @@ CHECK		= sparse
 
 CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
 		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
-NOSTDINC_FLAGS  =
+NOSTDINC_FLAGS :=
 CFLAGS_MODULE   =
 AFLAGS_MODULE   =
 LDFLAGS_MODULE  =