This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: no multi-arch & elision
- From: "H.J. Lu" <hjl dot tools at gmail dot com>
- To: Andi Kleen <andi at firstfloor dot org>
- Cc: Markus Trippelsdorf <markus at trippelsdorf dot de>, "Carlos O'Donell" <carlos at redhat dot com>, Andreas Jaeger <aj at suse dot com>, GNU C Library <libc-alpha at sourceware dot org>, Torvald Riegel <triegel at redhat dot com>, Rich Felker <dalias at aerifal dot cx>, Roland McGrath <roland at hack dot frob dot com>, "Joseph S. Myers" <joseph at codesourcery dot com>
- Date: Tue, 2 Jul 2013 14:53:22 -0700
- Subject: Re: no multi-arch & elision
- References: <20130702155326 dot GA6123 at two dot firstfloor dot org> <20130702171843 dot GA6555 at x4> <20130702201117 dot GB6123 at two dot firstfloor dot org> <20130702202122 dot GA518 at x4> <20130702203505 dot GC6123 at two dot firstfloor dot org> <20130702204300 dot GB518 at x4> <20130702205313 dot GD6123 at two dot firstfloor dot org> <CAMe9rOqsFOqypxF7DM-oyyQVeeh12XoO-yGbr+RwSH5MSUa7bQ at mail dot gmail dot com> <20130702211958 dot GE6123 at two dot firstfloor dot org> <CAMe9rOoM+WYG=+iB1s_JgKCCe+nO-GO_hFnB2J9zs6c2Gc45Gw at mail dot gmail dot com> <20130702213947 dot GG6123 at two dot firstfloor dot org>
On Tue, Jul 2, 2013 at 2:39 PM, Andi Kleen <andi@firstfloor.org> wrote:
> On Tue, Jul 02, 2013 at 02:23:57PM -0700, H.J. Lu wrote:
>> On Tue, Jul 2, 2013 at 2:19 PM, Andi Kleen <andi@firstfloor.org> wrote:
>> >> > Copying HJ, he helped me originally with the new x86/ setup.
>> >> > Any ideas?
>> >> >
>> >>
>> >> We can't use the multi-arch(ifunc) feature without enabling
>> >> multi-arch(ifunc). We can put elision-conf.c under the
>> >> "multichar" subdirectory.
>> >
>> > Don't need ifunc anymore, so that's ok.
>> >
>> > Where would multichar be? It doesn't seem to exist today.
>>
>> It should be "multiarch", like
>>
>> nptl/sysdeps/unix/sysv/linux/x86/multiarch
This exposes:
http://sourceware.org/bugzilla/show_bug.cgi?id=14941
> The problem is that without multiarch the main glibc does
> not export __get_cpu_features. This could be fixed,
> but would need more changes.
>
> One way would be to disable elision without multiarch?
> So move the files back into the multiarch directories.
>
> Or the other alternative is just calling CPUID directly
> without relying on any multiarch infrastructure
> (the really early versions of the patch kit did that)
>
> I lean towards the later. Comments?
>
CPUID feature support is multiarch. Disable multiarch
should disable CPUID feature support.
--
H.J.