Too many people have CFLAGS set to support building userspace.
And now Kbuild picks up CFLAGS this caused troubles.
Although people should realise that setting CFLAGS has
a 'global' effect the impact on the kernel build is a suprise.
So change kbuild to pick up value from KCFLAGS that is
much less used.
When kbuild pick up a value it will warn like this:
Makefile:544: "WARNING: Appending $KCFLAGS (-O3) from environment to kernel $CFLAGS"
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Bächler <thomas@archlinux.org>
Cc: David Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@redhat.com>
KBUILD_CFLAGS += $(call cc-option,-Wno-pointer-sign,)
# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
KBUILD_CFLAGS += $(call cc-option,-Wno-pointer-sign,)
# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
-KBUILD_CPPFLAGS += $(CPPFLAGS)
-KBUILD_AFLAGS += $(AFLAGS)
-KBUILD_CFLAGS += $(CFLAGS)
+# But warn user when we do so
+warn-assign = \
+$(warning "WARNING: Appending $$K$(1) ($(K$(1))) from $(origin K$(1)) to kernel $$$(1)")
+
+ifneq ($(KCPPFLAGS),)
+ $(call warn-assign,CPPFLAGS)
+ KBUILD_CPPFLAGS += $(KCPPFLAGS)
+endif
+ifneq ($(KAFLAGS),)
+ $(call warn-assign,AFLAGS)
+ KBUILD_AFLAGS += $(KAFLAGS)
+endif
+ifneq ($(KCFLAGS),)
+ $(call warn-assign,CFLAGS)
+ KBUILD_CFLAGS += $(KCFLAGS)
+endif
# Use --build-id when available.
LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
# Use --build-id when available.
LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\