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: Sam Ravnborg <sam@ravnborg.org>
diff --git a/arch/um/Makefile-x86_64 b/arch/um/Makefile-x86_64
index 8836f0d..bcfd6ea 100644
--- a/arch/um/Makefile-x86_64
+++ b/arch/um/Makefile-x86_64
@@ -14,7 +14,7 @@
CHECKFLAGS += -m64
KBUILD_AFLAGS += -m64
LDFLAGS += -m elf_x86_64
-CPPFLAGS += -m64
+KBUILD_CPPFLAGS += -m64
ELF_ARCH := i386:x86-64
ELF_FORMAT := elf64-x86-64