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/alpha/Makefile b/arch/alpha/Makefile
index 1b704ee..2f283b2 100644
--- a/arch/alpha/Makefile
+++ b/arch/alpha/Makefile
@@ -84,7 +84,7 @@
# For TSUNAMI, we must have the assembler not emulate our instructions.
# The same is true for IRONGATE, POLARIS, PYXIS.
# BWX is most important, but we don't really want any emulation ever.
-CFLAGS += $(cflags-y) -Wa,-mev6
+KBUILD_CFLAGS += $(cflags-y) -Wa,-mev6
head-y := arch/alpha/kernel/head.o