[Bug libfortran/50016] The fortran program 's io is very slow

["xunxun1982 at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50016

--- Comment #7 from PcX <xunxun1982 at gmail dot com> 2011-08-08 12:05:47 UTC ---
(In reply to comment #6)
> Maybe this is MingW specific?
> 
> I haven't tested this,  but here goes my guess:
> 
> Since in the write loop we're jumping back and forth across the file, the
> buffer must be frequently flushed; in libgfortran/io/unix.c (buf_flush) we have
> in the trunk and 4.6 branch:
> 
> #ifdef _WIN32
>   _commit (s->fd);
> #endif
> 
> If this is some kind of win32 equivalent to fsync(), i.e. commit stuff to disk,
> then it's no surprise it's slow?
> 
> This code was added to buf_flush() as a response to
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44698 .

That sounds reasonable.
So this bug is fixed in the trunk, but haven't been backported to 4.6?