Re: Non-portable m4 check in autoconf 2.64, 2.65, HEAD

[Joel E. Denny]

Hi Eric,

On Fri, 27 Nov 2009, Eric Blake wrote:

> According to Harald van Dijk on 11/26/2009 11:32 AM:
> > The configure script of autoconf 2.64/2.65/HEAD fails to detect a
> > suitable m4 on my system.
> > I have GNU M4 1.4.13. The problem is that I'm using dash for /bin/sh
> > (and my dash supports LINENO so configure doesn't silently use bash
> > instead), and the m4 detection doesn't work when echo \1 prints ^A.
> 
> That means bison needs to update its autoconf submodule to today, or it
> will suffer from the same problem in its reuse of the broken m4.m4 test.

Thanks.  I pushed the first patch below to master and branch-2.5.  I 
pushed the second to branch-2.4.2.

>From c843aaab352ab1f40c7d218fb5bb2c6fd6fd3a88 Mon Sep 17 00:00:00 2001
From: Joel E. Denny <address@hidden>
Date: Tue, 15 Dec 2009 18:56:52 -0500
Subject: [PATCH] autoconf: update to latest for fix of M4 detection.

Reported by Eric Blake.
* submodules/autoconf: Update.
---
 ChangeLog           |    6 ++++++
 submodules/autoconf |    2 +-
 2 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 897b54a..2c5d33e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2009-12-15  Joel E. Denny  <address@hidden>
 
+       autoconf: update to latest for fix of M4 detection.
+       Reported by Eric Blake.
+       * submodules/autoconf: Update.
+
+2009-12-15  Joel E. Denny  <address@hidden>
+
        portability: use -DGNULIB_POSIXCHECK.
        Reported by Eric Blake.  See discussions at
        <http://lists.gnu.org/archive/html/bug-bison/2009-09/msg00008.html>
diff --git a/submodules/autoconf b/submodules/autoconf
index 936160f..81074ea 160000
--- a/submodules/autoconf
+++ b/submodules/autoconf
@@ -1 +1 @@
-Subproject commit 936160f7619cb7fddbc424bb5cb9a2f997d8e166
+Subproject commit 81074eaa201a289d11b6be05e0c78afbe5ff79f5
-- 
1.5.4.3

>From dfff6628178e75cc2d23ad574f14bc540249258c Mon Sep 17 00:00:00 2001
From: Joel E. Denny <address@hidden>
Date: Tue, 15 Dec 2009 19:11:42 -0500
Subject: [PATCH] Import M4 detection fix from Autoconf.

Reported by Eric Blake.
* m4/m4.m4: Copy serial 10.
---
 ChangeLog |    6 ++++++
 m4/m4.m4  |    4 ++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index c6a2750..d419d50 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2009-12-15  Joel E. Denny  <address@hidden>
+
+       Import M4 detection fix from Autoconf.
+       Reported by Eric Blake.
+       * m4/m4.m4: Copy serial 10.
+
 2009-12-14  Joel E. Denny  <address@hidden>
 
        Enable assertion output and --disable-assert for configure.
diff --git a/m4/m4.m4 b/m4/m4.m4
index 096fb28..c6b64b0 100644
--- a/m4/m4.m4
+++ b/m4/m4.m4
@@ -1,4 +1,4 @@
-# m4.m4 serial 9
+# m4.m4 serial 10
 
 # Copyright (C) 2000, 2006, 2007, 2008, 2009 Free Software Foundation,
 # Inc.
@@ -29,7 +29,7 @@ AC_PATH_PROGS_FEATURE_CHECK([M4], [m4 gm4 gnum4],
       ac_snippet=change'quote(<,>)in''dir(<if''def>,mac,bug)'
       ac_snippet=${ac_snippet}pat'subst(a,\(b\)\|\(a\),\1)d'nl
       test -z "`$ac_path_M4 -F conftest.m4f </dev/null 2>&1`" \
-      && test -z "`echo $ac_snippet | $ac_path_M4 --trace=mac 2>&1`" \
+      && test -z "`AS_ECHO([$ac_snippet]) | $ac_path_M4 --trace=mac 2>&1`" \
       && test -f conftest.m4f \
       && ac_cv_path_M4=$ac_path_M4 ac_path_M4_found=:
       rm -f conftest.m4f],
-- 
1.5.4.3