Support for Intel X1000

[Joseph Myers]

On Tue, 12 May 2015, Kinsella, Ray wrote:

> Clearly no changes are needed to glibc for this - as it already provides
> a UP build, however I wanted to socialize the approach to fixing the

glibc does not provide a UP build.  The UP conditionals in glibc should be 
presumed bitrotten, and should be removed; there is no supported configure 
option to enable them.

(The right way to use different atomics in builds for different processors 
is to move to using __atomic_* as far as possible when building with 
sufficiently recent GCC versions and then have GCC deal with the different 
atomics.  But that's about using different sequences that are genuinely 
atomic (have the required compare-and-exchange semantics, etc.), not about 
using non-atomic sequences when atomic ones should be used.  glibc always 
requires atomic compare-and-exchange to be available in some form, whether 
through hardware instructions or kernel helpers, and does not support 
processor/kernel combinations without such an operation.)

-- 
Joseph S. Myers
joseph@codesourcery.com