Commit 06c5040c authored by Sam Ravnborg's avatar Sam Ravnborg
Browse files

kbuild: enable 'make CPPFLAGS=...' to add additional options to CPP 



The variable CPPFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.

This patch replace use of CPPFLAGS with KBUILD_CPPFLAGS all over the
tree and enabling one to use:
make CPPFLAGS=...
to specify additional CPP commandline options.

Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k, s390

Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
parent 52bcc330

Documentation/kbuild/makefiles.txt

+1 −1
Original line number Diff line number Diff line
@@ -1099,7 +1099,7 @@ When kbuild executes, the following steps are followed (roughly): 
	specified options when building the target vmlinux.lds.



	When building the *.lds target, kbuild uses the variables:

	CPPFLAGS	: Set in top-level Makefile

	KBUILD_CPPFLAGS	: Set in top-level Makefile

	EXTRA_CPPFLAGS	: May be set in the kbuild makefile

	CPPFLAGS_$(@F)  : Target specific flags.

	                  Note that the full filename is used in this

Makefile

+7 −6
Original line number Diff line number Diff line
@@ -318,7 +318,7 @@ LINUXINCLUDE := -Iinclude \ 
                   $(if $(KBUILD_SRC),-Iinclude2 -I$(srctree)/include) \

		   -include include/linux/autoconf.h



CPPFLAGS        := -D__KERNEL__ $(LINUXINCLUDE)

KBUILD_CPPFLAGS := -D__KERNEL__ $(LINUXINCLUDE)



KBUILD_CFLAGS   := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \

		   -fno-strict-aliasing -fno-common \
@@ -334,7 +334,7 @@ export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC 
export CPP AR NM STRIP OBJCOPY OBJDUMP MAKE AWK GENKSYMS PERL UTS_MACHINE

export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS



export CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS

export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS

export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE

export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
@@ -523,7 +523,8 @@ KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,) 
# disable pointer signed / unsigned warnings in gcc 4.0

KBUILD_CFLAGS += $(call cc-option,-Wno-pointer-sign,)



# Add user supplied AFLAGS and CFLAGS as the last assignments

# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments

KBUILD_CPPFLAGS += $(CPPFLAGS)

KBUILD_AFLAGS   += $(AFLAGS)

KBUILD_CFLAGS   += $(CFLAGS)
@@ -1507,7 +1508,7 @@ quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)) 




a_flags = -Wp,-MD,$(depfile) $(KBUILD_AFLAGS) $(AFLAGS_KERNEL) \

	  $(NOSTDINC_FLAGS) $(CPPFLAGS) \

	  $(NOSTDINC_FLAGS) $(KBUILD_CPPFLAGS) \

	  $(modkern_aflags) $(EXTRA_AFLAGS) $(AFLAGS_$(basetarget).o)



quiet_cmd_as_o_S = AS      $@

arch/arm/Makefile

+2 −2
Original line number Diff line number Diff line
@@ -32,11 +32,11 @@ KBUILD_CFLAGS +=-fno-omit-frame-pointer -mapcs -mno-sched-prolog 
endif



ifeq ($(CONFIG_CPU_BIG_ENDIAN),y)

CPPFLAGS	+= -mbig-endian

KBUILD_CPPFLAGS	+= -mbig-endian

AS		+= -EB

LD		+= -EB

else

CPPFLAGS	+= -mlittle-endian

KBUILD_CPPFLAGS	+= -mlittle-endian

AS		+= -EL

LD		+= -EL

endif

arch/ia64/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -29,7 +29,7 @@ cflags-y := -pipe $(EXTRA) -ffixed-r13 -mfixed-range=f12-f15,f32-f127 \ 
CFLAGS_KERNEL	:= -mconstant-gp



GAS_STATUS	= $(shell $(srctree)/arch/ia64/scripts/check-gas "$(CC)" "$(OBJDUMP)")

CPPFLAGS += $(shell $(srctree)/arch/ia64/scripts/toolchain-flags "$(CC)" "$(OBJDUMP)" "$(READELF)")

KBUILD_CPPFLAGS += $(shell $(srctree)/arch/ia64/scripts/toolchain-flags "$(CC)" "$(OBJDUMP)" "$(READELF)")



ifeq ($(GAS_STATUS),buggy)

$(error Sorry, you need a newer version of the assember, one that is built from	\

arch/powerpc/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -75,7 +75,7 @@ CPPFLAGS-$(CONFIG_PPC32) := -Iarch/$(ARCH) 
AFLAGS-$(CONFIG_PPC32)	:= -Iarch/$(ARCH)

CFLAGS-$(CONFIG_PPC64)	:= -mminimal-toc -mtraceback=none  -mcall-aixdesc

CFLAGS-$(CONFIG_PPC32)	:= -Iarch/$(ARCH) -ffixed-r2 -mmultiple

CPPFLAGS	+= $(CPPFLAGS-y)

KBUILD_CPPFLAGS	+= $(CPPFLAGS-y)

KBUILD_AFLAGS	+= $(AFLAGS-y)

KBUILD_CFLAGS	+= -msoft-float -pipe $(CFLAGS-y)

CPP		= $(CC) -E $(KBUILD_CFLAGS)

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