bootstrap/5149: gcc-20011217 reads beyond EOF on cygwin

[Christopher Faylor]

The following reply was made to PR bootstrap/5149; it has been noted by GNATS.

From: Christopher Faylor <cgf@redhat.com>
To: Werner Tuchan <tuwn@gmx.net>
Cc: Neil Booth <neil@daikokuya.demon.co.uk>, neil@gcc.gnu.org,
   gcc-bugs@gcc.gnu.org, gcc-gnats@gcc.gnu.org, cygwin@cygwin.com
Subject: Re: bootstrap/5149: gcc-20011217 reads beyond EOF on cygwin
Date: Fri, 21 Dec 2001 12:20:07 -0500

 On Fri, Dec 21, 2001 at 03:42:14PM +0100, Werner Tuchan wrote:
 >> Weird.  The bytes after EOF are a mixture of NULs and 0xc0.  Is 0xc0
 >> of special significance in Windows?  Is your version of cygwin the
 >> latest?  I recall some talk about mmap bugs in cygwin.
 >
 >The cygwin version is pretty recent. Two weeks old or so. The data after EOF
 >is only garbage. I've seen different values than 0x0 or 0xc0 in the error
 >messages. Windows propably doesn't clear the page before mapping the file
 >onto it. There is likely a different behaviour here between Windows ME and
 >NT.
 
 Can I ask why we'd be reading beyond EOF?  Is it guaranteed that bytes beyond
 EOF will be zero on UNIX?
 
 cgf