glibc-2.14-2 fails to build on s390x (F-15) with

...
In file included from ../sysdeps/s390/s390-64/utf16-utf32-z9.c:337:0:
../iconv/skeleton.c: In function 'gconv':
../iconv/skeleton.c:687:16: warning: variable 'nstatus' set but not used [-Wunused-but-set-variable]
../iconv/loop.c:437:7: warning: array subscript is above array bounds [-Warray-bounds]
../iconv/loop.c:437:7: warning: array subscript is above array bounds [-Warray-bounds]
../iconv/loop.c: Assembler messages:
../iconv/loop.c:332: Error: unknown pseudo-op: `.machine'
../iconv/loop.c:333: Error: unknown pseudo-op: `.machine'
../iconv/loop.c:335: Error: unknown pseudo-op: `.machine'
../iconv/loop.c:437: Error: unknown pseudo-op: `.machine'
../iconv/loop.c:438: Error: unknown pseudo-op: `.machine'
../iconv/loop.c:440: Error: unknown pseudo-op: `.machine'
../iconv/loop.c:332: Error: unknown pseudo-op: `.machine'
../iconv/loop.c:333: Error: unknown pseudo-op: `.machine'
../iconv/loop.c:335: Error: unknown pseudo-op: `.machine'
...

Probably F-15 has older gas (binutils-2.21.51.0.6-2.fc15) than expected by upstream glibc commit 27390476. And because Fedora's toolchain defaults to -march=z9-109 we can revert this commit I think.

full build logs are available from http://s390.koji.fedoraproject.org/koji/taskinfo?taskID=388464