Default ISA/tuning flags for GCC, --enable-kernel= level for glibc

[Gerd Hoffmann]

Jakub Jelinek wrote:

> For glibc 2.9 (F10) it would suffice to just have .27, but for rawhide
> .29 introduces futex bitset and realtime clock support, which means an extra
> syscall for every threaded program.  We could bump it in steps, first start
> requiring .27 and then if .29 is sufficiently stable in a month (or when
> we really need to freeze), rebuild just glibc requiring a newer kernel.

Can we *please* wait a bit until raising the bar *that* high?  Breaking
mock builds for rawhide on F9/10 releases is a really bad idea IMHO.
Which meas supporting at least 2.6.27.  Maybe in a year when F9 is EOL
and F10 has a 2.6.29 kernel update we can reconsider 2.6.29.

cheers,
  Gerd