- better distinction between CFLAGS and CPPFLAGS.
diff --git a/Makefile.flags b/Makefile.flags
index 0c680f9..bb5cef0 100644
--- a/Makefile.flags
+++ b/Makefile.flags
@@ -13,7 +13,9 @@
 	-include include/autoconf.h \
 	-D_GNU_SOURCE -DNDEBUG \
 	$(if $(CONFIG_LFS),-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64) \
-	-D"BB_VER=KBUILD_STR($(BB_VER))" -DBB_BT=AUTOCONF_TIMESTAMP \
+	-D"BB_VER=KBUILD_STR($(BB_VER))" -DBB_BT=AUTOCONF_TIMESTAMP
+
+CFLAGS += \
 	-Wall -Wstrict-prototypes -Wshadow -Werror -Wundef \
 	-funsigned-char -fno-builtin-strlen -finline-limit=0 -static-libgcc \
 	-Os -falign-functions=1 -falign-jumps=1 -falign-loops=1 \