Old compiler optimizations in installed headers

[Roland McGrath]

I think that all makes perfect sense.  Starting with 4.1 or 4.3 is a
completely reasonable conservative starting place.

I think we should consider the minimum GCC version required for
building libc itself as the only clear upper bound on the minimum
GCC version for which we bother to maintain any optimizations in
headers.  Keeping the minimum for header optimizations at a lower
version requires continual proof that it matters to anyone, any time
it looks like raising it would ease the maintenance burden.


Thanks,
Roland