Bug workarond---GNU libc

Back in '98 or '99 I reported a bug to glibc that

	memchr(x,(size_t)-1)

failed when it should not have, on a 64-bit system.  I thought it was
patched, but apparently the bug was never patched, or regressed, or
something, because today,

	memchr(p,(size_t)-1)

on a 64-bit system is *broken*.

Sigh.