[PATCH] Protect _dl_profile_fixup data-dependency order [BZ #23690]

[Florian Weimer]

* Tulio Magno Quites Machado Filho:

> Yes.  There is already something attached to the bug report, but it does
> require dozens of threads to reproduce here.
> If you're fine with that, I can adapt it.

That's okay (depending on the exact value of “dozens” 8-).

I assume it's burning CPU all the time?  Then you should put it into
nptl/ because those tests run serialized.  If you think it should run
longer than five second, we perhaps should make it an xtest.

Thanks,
Florian