kbuild: add machine size to CHECKFLAGS

By default, sparse assumes a 64bit machine when compiled on x86-64
and 32bit when compiled on anything else.

This can of course create all sort of problems for the other archs, like
issuing false warnings ('shift too big (32) for type unsigned long'), or
worse, failing to emit legitimate warnings.

Fix this by adding the -m32/-m64 flag, depending on CONFIG_64BIT,
to CHECKFLAGS in the main Makefile (and so for all archs).
Also, remove the now unneeded -m32/-m64 in arch specific Makefiles.

Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Makefile

@@ -877,6 +877,9 @@ endif
 # insure the checker run with the right endianness
 CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
 
+# the checker needs the correct machine size
+CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
+
 # Default kernel image to build when no specific target is given.
 # KBUILD_IMAGE may be overruled on the command line or
 # set in the environment

arch/alpha/Makefile

@@ -11,7 +11,7 @@
 NM := $(NM) -B
 
 LDFLAGS_vmlinux	:= -static -N #-relax
-CHECKFLAGS	+= -D__alpha__ -m64
+CHECKFLAGS	+= -D__alpha__
 cflags-y	:= -pipe -mno-fp-regs -ffixed-8
 cflags-y	+= $(call cc-option, -fno-jump-tables)
 

arch/arm/Makefile

@@ -135,7 +135,7 @@ endif
 KBUILD_CFLAGS	+=$(CFLAGS_ABI) $(CFLAGS_ISA) $(arch-y) $(tune-y) $(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,)) -msoft-float -Uarm
 KBUILD_AFLAGS	+=$(CFLAGS_ABI) $(AFLAGS_ISA) $(arch-y) $(tune-y) -include asm/unified.h -msoft-float
 
-CHECKFLAGS	+= -D__arm__ -m32
+CHECKFLAGS	+= -D__arm__
 
 #Default value
 head-y		:= arch/arm/kernel/head$(MMUEXT).o

arch/arm64/Makefile

@@ -78,7 +78,7 @@ LDFLAGS		+= -maarch64linux
 UTS_MACHINE	:= aarch64
 endif
 
-CHECKFLAGS	+= -D__aarch64__ -m64
+CHECKFLAGS	+= -D__aarch64__
 
 ifeq ($(CONFIG_ARM64_MODULE_PLTS),y)
 KBUILD_LDFLAGS_MODULE	+= -T $(srctree)/arch/arm64/kernel/module.lds

arch/ia64/Makefile

@@ -18,7 +18,7 @@ READELF := $(CROSS_COMPILE)readelf
 
 export AWK
 
-CHECKFLAGS	+= -m64 -D__ia64=1 -D__ia64__=1 -D_LP64 -D__LP64__
+CHECKFLAGS	+= -D__ia64=1 -D__ia64__=1 -D_LP64 -D__LP64__
 
 OBJCOPYFLAGS	:= --strip-all
 LDFLAGS_vmlinux	:= -static

arch/mips/Makefile

@@ -309,9 +309,6 @@ ifdef CONFIG_MIPS
 CHECKFLAGS += $(shell $(CC) $(KBUILD_CFLAGS) -dM -E -x c /dev/null | \
 	egrep -vw '__GNUC_(|MINOR_|PATCHLEVEL_)_' | \
 	sed -e "s/^\#define /-D'/" -e "s/ /'='/" -e "s/$$/'/" -e 's/\$$/&&/g')
-ifdef CONFIG_64BIT
-CHECKFLAGS		+= -m64
-endif
 endif
 
 OBJCOPYFLAGS		+= --remove-section=.reginfo

arch/parisc/Makefile

@@ -28,7 +28,7 @@ export LIBGCC
 
 ifdef CONFIG_64BIT
 UTS_MACHINE	:= parisc64
-CHECKFLAGS	+= -D__LP64__=1 -m64
+CHECKFLAGS	+= -D__LP64__=1
 CC_ARCHES	= hppa64
 LD_BFD		:= elf64-hppa-linux
 else # 32-bit

arch/sparc/Makefile

@@ -39,7 +39,7 @@ else
 # sparc64
 #
 
-CHECKFLAGS    += -D__sparc__ -D__sparc_v9__ -D__arch64__ -m64
+CHECKFLAGS    += -D__sparc__ -D__sparc_v9__ -D__arch64__
 LDFLAGS       := -m elf64_sparc
 export BITS   := 64
 UTS_MACHINE   := sparc64

arch/x86/Makefile

@@ -94,7 +94,7 @@ ifeq ($(CONFIG_X86_32),y)
 else
         BITS := 64
         UTS_MACHINE := x86_64
-        CHECKFLAGS += -D__x86_64__ -m64
+        CHECKFLAGS += -D__x86_64__
 
         biarch := -m64
         KBUILD_AFLAGS += -m64