Re: bootstrap/3162: libiberty's test for working strncmp fails on some systems

Re: bootstrap/3162: libiberty's test for working strncmp fails on some systems

[rodrigc]

Synopsis: libiberty's test for working strncmp fails on some systems

State-Changed-From-To: open->closed
State-Changed-By: rodrigc
State-Changed-When: Sat Feb 23 18:55:40 2002
State-Changed-Why:
    Information from this PR added to PR 3163:
    http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=3163

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=3162

bootstrap/3162: libiberty's test for working strncmp fails on some systems

[john]

>Number:         3162
>Category:       bootstrap
>Synopsis:       libiberty's test for working strncmp fails on some systems
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Jun 13 04:16:02 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:
	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.
>How-To-Repeat:
	Run configure
>Fix:
--- 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

>Release-Note:
>Audit-Trail:
>Unformatted: