diff options
| author | David Woodhouse <dwmw2@infradead.org> | 2012-12-20 21:51:55 +0000 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2012-12-20 14:37:18 -0800 |
| commit | ffee0de411fd4f74f3b788892eeb075abbf26c52 (patch) | |
| tree | 1b1bd2751822cdabca7d44de635369c9091ae624 /arch/x86/Makefile | |
| parent | 29594404d7fe73cd80eaa4ee8c43dcc53970c60e (diff) | |
| download | lwn-ffee0de411fd4f74f3b788892eeb075abbf26c52.tar.gz lwn-ffee0de411fd4f74f3b788892eeb075abbf26c52.zip | |
x86: Default to ARCH=x86 to avoid overriding CONFIG_64BIT
It is easy to waste a bunch of time when one takes a 32-bit .config
from a test machine and try to build it on a faster 64-bit system, and
its existing setting of CONFIG_64BIT=n gets *changed* to match the
build host. Similarly, if one has an existing build tree it is easy
to trash an entire build tree that way.
This is because the default setting for $ARCH when discovered from
'uname' is one of the legacy pre-x86-merge values (i386 or x86_64),
which effectively force the setting of CONFIG_64BIT to match. We should
default to ARCH=x86 instead, finally completing the merge that we
started so long ago.
This patch preserves the behaviour of the legacy ARCH settings for commands
such as:
make ARCH=x86_64 randconfig
make ARCH=i386 randconfig
... since making the value of CONFIG_64BIT actually random in that situation
is not desirable.
In time, perhaps we can retire this legacy use of the old ARCH= values.
We already have a way to override values for *any* config option, using
$KCONFIG_ALLCONFIG, so it could be argued that we don't necessarily need
to keep ARCH={i386,x86_64} around as a special case just for overriding
CONFIG_64BIT.
We'd probably at least want to add a way to override config options from
the command line ('make CONFIG_FOO=y oldconfig') before we talk about doing
that though.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Link: http://lkml.kernel.org/r/1356040315.3198.51.camel@shinybook.infradead.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/Makefile')
| -rw-r--r-- | arch/x86/Makefile | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 05afcca66de6..fa981ca1bfe5 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -2,7 +2,11 @@ # select defconfig based on actual architecture ifeq ($(ARCH),x86) + ifeq ($(shell uname -m),x86_64) + KBUILD_DEFCONFIG := x86_64_defconfig + else KBUILD_DEFCONFIG := i386_defconfig + endif else KBUILD_DEFCONFIG := $(ARCH)_defconfig endif |