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

[Neil Booth <neil@daikokuya.demon.co.uk>]

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

From: Neil Booth <neil@daikokuya.demon.co.uk>
To: Zack Weinberg <zack@codesourcery.com>
Cc: Werner Tuchan <tuwn@gmx.net>, neil@gcc.gnu.org, gcc-bugs@gcc.gnu.org,
	gcc-gnats@gcc.gnu.org
Subject: Re: bootstrap/5149: gcc-20011217 reads beyond EOF on cygwin
Date: Thu, 20 Dec 2001 19:09:10 +0000

 Zack Weinberg wrote:-
 
 > No.  But the AC_FUNC_MMAP_FILE macro (gcc/aclocal.m4) already executes
 > a test program to determine whether or not mmap works the way we want.
 > It would be easy enough to add a check that byte (len+1) of its test
 > file is a NUL.  [And we'd better not be looking at byte len+2, or
 > we'll segfault if the file length is one less than a multiple of
 > PAGE_SIZE.]
 
 Looking at the dump Werner supplied, filled with 0xc0 and NULs, I fear
 this could pass on cygwin by fluke.  Better just to blacklist it IMO.
 HAVE_BROKEN_MMAP or something.
 
 Neil.