SUBARCH := $(shell uname -m | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
-e s/arm.*/arm/ -e s/sa110/arm/ \
-e s/s390x/s390/ -e s/parisc64/parisc/ \
- -e s/ppc.*/powerpc/ -e s/mips.*/mips/ )
+ -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
+ -e s/sh[234].*/sh/ )
# Cross compiling and selecting different set of gcc/bin-utils
# ---------------------------------------------------------------------------
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)%,%,\