Re: [GNU Autoconf 2.61] testsuite: 221 failed

[Ralf Wildenhues]

This is a followup to two related bug reports:
<http://thread.gmane.org/gmane.comp.sysutils.autoconf.bugs/5409>
<http://thread.gmane.org/gmane.comp.sysutils.autoconf.bugs/5465>

* Paul Eggert wrote on Wed, Jan 10, 2007 at 07:30:37AM CET:
> I cannot reproduce the problem on my Solaris 8 (sparc) host.

I can reproduce the problem on GNU/Linux with bash-3.2 (but not 3.1)
and on Solaris 8 with bash 2.03.0(1) but not on other Solaris versions
(which also happen to have different bash versions as /bin/bash).

This is how I can reproduce the issue interactively:
$ ./bash
bash$ f="1234567890
1234567890
"; for i in 1 2 3 4 5 6 7 8 9 10 11 12; do f=$f$f; done; echo "$f" | sed 1q

Weird though, I don't yet see an easy way to reproduce it
non-interactively.

I did a rough check of the Autoconf sources, and I think the patch below
fixes the only instance of this issue, but am pretty certain that users'
macros and configure.ac scripts are likely to contain more of those.

Could you please test whether this fixes the bug for you?
Ok to apply?

Thanks,
Ralf

2007-01-10  Ralf Wildenhues  <address@hidden>

        * lib/autoconf/programs.m4 (AC_PROG_SED): When closing a pipe
        early on the reader side, drop stderr of the input to avoid
        `broken pipe' error output; this may happen even with shell
        builtin `echo' of some bash versions.
        Reports by Ian Macdonald <address@hidden> and Sam Sexton
        <address@hidden>.

Index: lib/autoconf/programs.m4
===================================================================
RCS file: /cvsroot/autoconf/autoconf/lib/autoconf/programs.m4,v
retrieving revision 1.63
diff -u -r1.63 programs.m4
--- lib/autoconf/programs.m4    17 Nov 2006 21:04:54 -0000      1.63
+++ lib/autoconf/programs.m4    10 Jan 2007 23:23:46 -0000
@@ -859,7 +859,7 @@
      for ac_i in 1 2 3 4 5 6 7; do
        ac_script="$ac_script$as_nl$ac_script"
      done
-     echo "$ac_script" | sed 99q >conftest.sed
+     echo "$ac_script" 2>/dev/null | sed 99q >conftest.sed
      $as_unset ac_script || ac_script=
      _AC_PATH_PROG_FEATURE_CHECK(SED, [sed gsed],
        [_AC_FEATURE_CHECK_LENGTH([ac_path_SED], [ac_cv_path_SED],