Use fstat64 to work out the size of a file if it is available as it
copes with a wider range of filesystems than the old fstat call.

Fixes bug #130020.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@5979 a5019735-40e9-0310-863c-91ae7b9d1cf9
2 files changed