[PATCH] Fix <bits/stdio.h> plus testcase

[Roland McGrath]

> 2004-08-10  Jakub Jelinek  <jakub@redhat.com>
> 
> 	* libio/bits/stdio.h (fread_unlocked): Cast 0 to (size_t).
> 	(fwrite_unlocked): When checking if size * n is <= 8, cast each
> 	argument to size_t individually.  Cast n to (void) instead of
> 	(size_t), surround with (), return (size_t) 0 if one of n or size
> 	is 0.  [BZ #316]
> 	* stdio-common/Makefile (tests): Add tst-unlockedio.
> 	* stdio-common/tst-unlockedio.c: New test.

Applied.