2006-10-04  Paul Eggert  <address@hidden>
	    Stepan Kasal  <address@hidden>
 
	* doc/autoconf.texi (Special Shell Variables): Autoconf-generated
	shell scripts no longer export BIN_SH, due to configuration
	hassles with this.  See, for example, Tonya Underwood's report
	<http://lists.gnu.org/archive/html/bug-autoconf/2006-10/msg00003.html>.
	* lib/m4sugar/m4sh.m4 (AS_BOURNE_COMPATIBLE): Don't set BIN_SH.
	(_AS_DETECT_BETTER_SHELL): Don't look in /usr/bin/posix.

Index: doc/autoconf.texi
===================================================================
RCS file: /cvsroot/autoconf/autoconf/doc/autoconf.texi,v
retrieving revision 1.1090
diff -u -r1.1090 autoconf.texi
--- doc/autoconf.texi	6 Oct 2006 15:31:26 -0000	1.1090
+++ doc/autoconf.texi	9 Oct 2006 14:04:18 -0000
@@ -11891,7 +11891,6 @@
 @evindex BIN_SH
 In Tru64, if @env{BIN_SH} is set to @code{xpg4}, subsidiary invocations of
 the standard shell conform to Posix.
-Autoconf-generated scripts export this variable when they start up.
 
 @item CDPATH
 @evindex CDPATH
Index: lib/m4sugar/m4sh.m4
===================================================================
RCS file: /cvsroot/autoconf/autoconf/lib/m4sugar/m4sh.m4,v
retrieving revision 1.196
diff -u -r1.196 m4sh.m4
--- lib/m4sugar/m4sh.m4	6 Oct 2006 15:31:26 -0000	1.196
+++ lib/m4sugar/m4sh.m4	9 Oct 2006 14:04:19 -0000
@@ -161,9 +161,10 @@
 # --------------------
 # Try to be as Bourne and/or POSIX as possible.
 #
-# FIXME: The assignment to BIN_SH is dubious; see
+# This does not set BIN_SH, due to the problems described in
 # <http://lists.gnu.org/archive/html/autoconf-patches/2006-03/msg00081.html>.
-# It might be better to remove it, but first please see
+# People who need BIN_SH should set it in their environment before invoking
+# configure; apparently this would include UnixWare, as described in
 # <http://lists.gnu.org/archive/html/bug-autoconf/2006-06/msg00025.html>.
 m4_define([AS_BOURNE_COMPATIBLE],
 [# Be Bourne compatible
@@ -177,7 +178,6 @@
 else
   case `(set -o) 2>/dev/null` in *posix*) set -o posix;; esac
 fi
-BIN_SH=xpg4; export BIN_SH # for Tru64
 DUALCASE=1; export DUALCASE # for MKS sh
 ])
 
@@ -223,16 +223,14 @@
 # The real workhorse for detecting a shell with the correct
 # features.
 #
-# FIXME: The '/usr/bin/posix' below works around a shell bug in OSF
-# <http://lists.gnu.org/archive/html/autoconf-patches/2006-03/msg00081.html>
-# but this causes a regression on OpenServer 6.0.0
+# In previous versions, we prepended /usr/posix/bin to the path, but that
+# caused a regression on OpenServer 6.0.0
 # <http://lists.gnu.org/archive/html/bug-autoconf/2006-06/msg00017.html>
-# The code should test for the OSF bug directly rather than look at
-# /usr/bin/posix here.
+# and on HP-UX 11.11, see the failure of test 120 in
+# <http://lists.gnu.org/archive/html/bug-autoconf/2006-10/msg00003.html>
 #
-# FIXME: The 'test -f "$as_shell.exe"' works around a problem in OS/2
-# <http://lists.gnu.org/archive/html/autoconf/2006-06/msg00038.html>
-# but we should replace the two test -f calls with a single AS_EXECUTABLE_P.
+# FIXME: The code should test for the OSF bug described in
+# <http://lists.gnu.org/archive/html/autoconf-patches/2006-03/msg00081.html>.
 #
 m4_defun_once([_AS_DETECT_BETTER_SHELL],
 [m4_wrap([m4_divert_text([M4SH-SANITIZE], [
@@ -245,7 +243,7 @@
 	 _AS_RUN([_AS_DETECT_SUGGESTED_BODY]) 2> /dev/null],
     [],
     [as_candidate_shells=
-    _AS_PATH_WALK([/usr/bin/posix$PATH_SEPARATOR/bin$PATH_SEPARATOR/usr/bin$PATH_SEPARATOR$PATH],
+    _AS_PATH_WALK([/bin$PATH_SEPARATOR/usr/bin$PATH_SEPARATOR$PATH],
       [case $as_dir in
 	 /*)
 	   for as_base in sh bash ksh sh5; do