Only use VKI_O_LARGEFILE on platforms where it exists.  This
unbreaks the build breakage on Darwin introduced in r11397, which
was a fix for #234064.  The breakage was subsequently reported
in #253420 and #253452, which this commit fixes.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@11406 a5019735-40e9-0310-863c-91ae7b9d1cf9
1 file changed