Re: bootstrap/3163: gcc/aclocal.m4 mmap test fails on UnixWare 7.1.1

Re: bootstrap/3163: gcc/aclocal.m4 mmap test fails on UnixWare 7.1.1

[bangerth]

Synopsis: gcc/aclocal.m4 mmap test fails on UnixWare 7.1.1

State-Changed-From-To: open->feedback
State-Changed-By: bangerth
State-Changed-When: Fri May  9 15:21:42 2003
State-Changed-Why:
    See Dara's question

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=3163

Re: bootstrap/3163: gcc/aclocal.m4 mmap test fails on UnixWare 7.1.1

[Dara Hazeghi]

The following reply was made to PR bootstrap/3163; it has been noted by GNATS.

From: Dara Hazeghi <dhazeghi@yahoo.com>
To: gcc-gnats@gcc.gnu.org, john@Calva.COM
Cc:  
Subject: Re: bootstrap/3163: gcc/aclocal.m4 mmap test fails on UnixWare 7.1.1
Date: Fri, 9 May 2003 01:19:29 -0700

 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit- 
 trail&database=gcc&pr=3163
 
 Hello,
 
 there have been no updates about this bug for over a year. Is this bug  
 reported still an issue on this platform with current releases of gcc?  
 Thanks,
 
 Dara
 

Re: bootstrap/3163: gcc/aclocal.m4 mmap test fails on UnixWare 7.1.1

[Craig Rodrigues]

The following reply was made to PR bootstrap/3163; it has been noted by GNATS.

From: Craig Rodrigues <rodrigc@attbi.com>
To: gcc-gnats@gcc.gnu.org, gcc-prs@gcc.gnu.org, john@Calva.COM,
   gcc-bugs@gcc.gnu.org, nobody@gcc.gnu.org
Cc:  
Subject: Re: bootstrap/3163: gcc/aclocal.m4 mmap test fails on UnixWare 7.1.1
Date: Sat, 23 Feb 2002 21:56:20 -0500

 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=3163
 
 
 john@calva.com posted this info  in PR 3162:
 
 libiberty/aclocal.m4 has a check to see if strncmp runs off the
 end of the string.  It incorrectly fails on systems where
 MAP_ANON(YMOUS) must be used without an open fd, for example
  UnixWare 7.1.1.
 
 --- libiberty/aclocal.m4.orig   Wed Nov 22 09:32:26 2000
 +++ libiberty/aclocal.m4        Wed Jun 13 12:48:35 2001
 @@ -21,8 +21,6 @@
  #ifndef MAP_ANON
  #ifdef MAP_ANONYMOUS
  #define MAP_ANON MAP_ANONYMOUS
 -#else
 -#define MAP_ANON MAP_FILE
  #endif
  #endif
  
 @@ -39,6 +37,10 @@
  {
  #if defined(HAVE_MMAP) || defined(HAVE_MMAP_ANYWHERE)
    char *p;
 +#ifdef MAP_ANON
 +  p = (char *) mmap (0, MAP_LEN, PROT_READ|PROT_WRITE,
 +                    MAP_ANON|MAP_PRIVATE, -1, 0);
 +#else
    int dev_zero;
  
    dev_zero = open ("/dev/zero", O_RDONLY);
 @@ -46,7 +48,8 @@
      exit (1);
   
    p = (char *) mmap (0, MAP_LEN, PROT_READ|PROT_WRITE,
 -                    MAP_ANON|MAP_PRIVATE, dev_zero, 0);
 +                    MAP_FILE|MAP_PRIVATE, dev_zero, 0);
 +#endif
    if (p == (char *)-1)
      exit (2);
    else
 
 
 

bootstrap/3163: gcc/aclocal.m4 mmap test fails on UnixWare 7.1.1

[john]

>Number:         3163
>Category:       bootstrap
>Synopsis:       gcc/aclocal.m4 mmap test fails on UnixWare 7.1.1
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Jun 13 04:46:05 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     John Hughes
>Release:        3.0 20010611 (prerelease)
>Organization:
CalvaEDI S.A.
>Environment:
System: UnixWare oceanic 5 7.1.1 i386 x86at SCO UNIX_SVR5


	
host: i586-sco-sysv5uw7.1.1
build: i586-sco-sysv5uw7.1.1
target: i586-sco-sysv5uw7.1.1
configured with: ../gcc-3.0-20010611/configure --prefix=/u/local --with-local_prefix=/u/local
>Description:
	To quote gcc/aclocal.m4:

/* 3. If we map two adjacent 1-page regions and unmap them both with
   one munmap, both must go away.

   Getting two adjacent 1-page regions with two mmap calls is slightly
   tricky.  All OS's tested skip over already-allocated blocks; therefore
   we have been careful to unmap all allocated regions in previous tests.
   HP/UX allocates pages backward in memory.  No OS has yet been observed
   to be so perverse as to leave unmapped space between consecutive calls
   to mmap.  */

Well, UnixWare 7.1.1 is that perverse system.  It seems to leave
one page between each mapping.

>How-To-Repeat:
	configure
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted: