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
diff --git a/arch/alpha/kernel/Makefile b/arch/alpha/kernel/Makefile
index ab6fa54..dccf052 100644
--- a/arch/alpha/kernel/Makefile
+++ b/arch/alpha/kernel/Makefile
@@ -3,7 +3,7 @@
#
extra-y := head.o vmlinux.lds
-EXTRA_AFLAGS := $(CFLAGS)
+EXTRA_AFLAGS := $(KBUILD_CFLAGS)
EXTRA_CFLAGS := -Werror -Wno-sign-compare
obj-y := entry.o traps.o process.o init_task.o osf_sys.o irq.o \
diff --git a/arch/alpha/lib/Makefile b/arch/alpha/lib/Makefile
index 266f78e..9b72c59 100644
--- a/arch/alpha/lib/Makefile
+++ b/arch/alpha/lib/Makefile
@@ -2,7 +2,7 @@
# Makefile for alpha-specific library files..
#
-EXTRA_AFLAGS := $(CFLAGS)
+EXTRA_AFLAGS := $(KBUILD_CFLAGS)
EXTRA_CFLAGS := -Werror
# Many of these routines have implementations tuned for ev6.