kbuild: enable 'make CFLAGS=...' to add additional options to CC
The variable CFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people over time has asked for a way to
pass in additional flags to gcc.
This patch replace use of CFLAGS with KBUILD_CFLAGS all over the
tree and enabling one to use:
make CFLAGS=...
to specify additional gcc commandline options.
One usecase is when trying to find gcc bugs but other
use cases has been requested too.
Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k
Test was simple to do a defconfig build, apply the patch and check
that nothing got rebuild.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/arch/ppc/Makefile b/arch/ppc/Makefile
index eee6264..43802e9 100644
--- a/arch/ppc/Makefile
+++ b/arch/ppc/Makefile
@@ -24,20 +24,20 @@
# The -Iarch/$(ARCH)/include is temporary while we are merging
CPPFLAGS += -Iarch/$(ARCH) -Iarch/$(ARCH)/include
AFLAGS += -Iarch/$(ARCH)
-CFLAGS += -Iarch/$(ARCH) -msoft-float -pipe \
+KBUILD_CFLAGS += -Iarch/$(ARCH) -msoft-float -pipe \
-ffixed-r2 -mmultiple
# No AltiVec instruction when building kernel
-CFLAGS += $(call cc-option, -mno-altivec)
+KBUILD_CFLAGS += $(call cc-option, -mno-altivec)
-CPP = $(CC) -E $(CFLAGS)
+CPP = $(CC) -E $(KBUILD_CFLAGS)
# Temporary hack until we have migrated to asm-powerpc
LINUXINCLUDE += -Iarch/$(ARCH)/include
CHECKFLAGS += -D__powerpc__
ifndef CONFIG_FSL_BOOKE
-CFLAGS += -mstring
+KBUILD_CFLAGS += -mstring
endif
cpu-as-$(CONFIG_4xx) += -Wa,-m405
@@ -46,7 +46,7 @@
cpu-as-$(CONFIG_E200) += -Wa,-me200
AFLAGS += $(cpu-as-y)
-CFLAGS += $(cpu-as-y)
+KBUILD_CFLAGS += $(cpu-as-y)
# Default to the common case.
KBUILD_DEFCONFIG := common_defconfig