gcc reports this warning with -Wclobbered:
util/oslib-posix.c: In function ‘os_mem_prealloc’:
util/oslib-posix.c:374:49: error: argument ‘memory’ might be clobbered by
‘longjmp’ or ‘vfork’ [-Werror=clobbered]
Fix this and simplify the code by using an existing macro.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>