• David Woodhouse's avatar
    x86: Default to ARCH=x86 to avoid overriding CONFIG_64BIT · ffee0de4
    David Woodhouse authored
    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: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
    Link: http://lkml.kernel.org/r/1356040315.3198.51.camel@shinybook.infradead.orgSigned-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
    ffee0de4
Makefile 46.7 KB