Notice clock_* functions in librt.so for old GLIBC_2.18 builds?

[Roland McGrath]

> Roland McGrath <roland@hack.frob.com> writes:
> 
> > Also, someone should try turning on -Wundef in the build and see if it
> > generates any warnings.
> 
> Long way to go.

Thanks for doing the exercise.  That is disappointing indeed, but it
doesn't look intractable.  I think we should get started ASAP on piecemeal
cleanup of these.  Perhaps we should even put -Wundef in now so everybody
has all the cases thrust before them, and change it to -Werror=undef
eventually when we're done cleaning up.

It probably makes sense to take them one macro at a time across all cases
rather than files at a time.  I suspect most are straightforward cases for
s/if/ifdef/.  Others (e.g. _POSIX_* et al) actually do properly want to be
"#if defined foo && foo" and the like.  At least a few seem like probable
actual bugs from missing #includes, albeit almost certainly benign ones not
affecting the #if resolution in actuality (RTLD_PRIVATE_ERRNO sticks out).


Thanks,
Roland