diff --git a/Makefile b/Makefile
index fbd9ff4a61e70cb629689f5083dd20da310ea3bf..6b047daa46cc124ee2edac15aaf7c13ed735f5e6 100644
--- a/Makefile
+++ b/Makefile
@@ -866,7 +866,8 @@ stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
 
 KBUILD_CFLAGS += $(stackp-flags-y)
 
-KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror
+KBUILD_CPPFLAGS-$(CONFIG_WERROR) += -Werror
+KBUILD_CPPFLAGS += $(KBUILD_CPPFLAGS-y)
 KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
 
 KBUILD_RUSTFLAGS-$(CONFIG_WERROR) += -Dwarnings