Re: Autoconf 2.53: improved fix for problems with CONFIG_SHELL=bash

[Akim Demaille]

| Perhaps the installers had set BASH_ENV to point to their .bashrc?
| That might explain the problem.  There is a similar problem with ENV
| in various shells, including Bash in some cases.  Sounds a bit weird,
| though -- why would someone put a "cd" command in their BASH_ENV?

Wow.  I was unaware of BASH_ENV/ENV!

| Anyway, If my guess is correct, the following untested patch should
| fix things.  But I would like some confirmation and advice before
| installing this.
| 
| 
| 2002-03-19  Paul Eggert  <address@hidden>
| 
|       * lib/m4sugar/m4sh.m4 (_AS_LINENO_PREPARE): Unset ENV and
|       BASH_ENV when reinvoking the shell, to work around problems
|       with installers who put "cd" commands in their environments.
| 
| --- m4sh.m4.~1.76.~   2002-03-18 22:13:55.000000000 -0800
| +++ m4sh.m4   2002-03-19 17:49:08.147121000 -0800
| @@ -507,6 +507,8 @@ m4_define([_AS_LINENO_PREPARE],
|        case $as_dir in
|        /*)
|          if ("$as_dir/$as_base" -c '_AS_LINENO_WORKS') 2>/dev/null; then
| +          AS_UNSET(ENV, /dev/null)
| +          AS_UNSET(BASH_ENV, /dev/null)
|            CONFIG_SHELL=$as_dir/$as_base
|            export CONFIG_SHELL
|            exec "$CONFIG_SHELL" "$[0]" ${1+"address@hidden"}

Even if it does not solve the current issue, I'm in favor of it.