current: ac_abs_top_builddir incorrect when building in place

[Maciej W. Rozycki]

Hello,

 When configuring for building in srcdir ac_abs_top_builddir gets set
incorrectly to $HOME.  This happens because ac_top_builddir is set to
empty and as the resulting `cd . && cd && pwd' command yields just that.

 Here is a fix that works for me.  Tested against 2.53 but a current
snapshot doesn't differ.  Please apply. 

2002-04-08  Maciej W. Rozycki  <address@hidden>

        * lib/autoconf/status.m4 (_AC_SRCPATHS): Handle the empty
        $ac_top_builddir case when setting $ac_abs_top_builddir.

  Maciej

-- 
+  Maciej W. Rozycki, Technical University of Gdansk, Poland   +
+--------------------------------------------------------------+
+        e-mail: address@hidden, PGP key available        +

autoconf-2.53-top_builddir.patch
diff -up --recursive --new-file autoconf-2.53.macro/lib/autoconf/status.m4 
autoconf-2.53/lib/autoconf/status.m4
--- autoconf-2.53.macro/lib/autoconf/status.m4  2002-03-04 14:34:20.000000000 
+0000
+++ autoconf-2.53/lib/autoconf/status.m4        2002-04-07 17:29:54.000000000 
+0000
@@ -161,9 +161,9 @@ case $srcdir in
     ac_top_srcdir=$ac_top_builddir$srcdir ;;
 esac
 # Don't blindly perform a `cd $1/$ac_foo && pwd` since $ac_foo can be
-# absolute.
+# absolute.  Also $ac_top_builddir may be empty.
 ac_abs_builddir=`cd $1 && cd $ac_builddir && pwd`
-ac_abs_top_builddir=`cd $1 && cd $ac_top_builddir && pwd`
+ac_abs_top_builddir=`cd $1 && cd $ac_top_builddir. && pwd`
 ac_abs_srcdir=`cd $1 && cd $ac_srcdir && pwd`
 ac_abs_top_srcdir=`cd $1 && cd $ac_top_srcdir && pwd`
 ])# _AC_SRCPATHS