How are CPU-optimized libraries supposed to work?

[Roland McGrath]

> Then why do we search CPU-optimized directories at all, if we don't
> support using the same sources built with different options?

The feature is there for finding all libraries, not just for libc.

Having some mismatch ld+libc cases work is worthwhile.  We have taken
special pains to make __thread vs no-__thread combinations work, for
example.  Making i386 vs i686 work is worthwhile too.  But there is no
generic principle by which you should expect this to already have worked,
or consider it a bug per se if it doesn't.  Any such support is a special case.