[JAVA] /bin/sh portability issues in gen-classlist.sh.in

[Paolo Bonzini]

>   # Only include generated files once.
> ! if test ! "${top_builddir}" -ef "@top_srcdir@"; then
>     echo "Adding generated files in builddir '${top_builddir}'."
>     # Currently the only generated files are in gnu.*.
>     (cd ${top_builddir}; @FIND@ gnu -follow -name '*.java' -print) |
> --- 55,61 ----
>   done
> 
>   # Only include generated files once.
> ! if test `cd "${top_builddir}"; pwd` != `cd "@top_srcdir@"; pwd`; then

Might be a problem when directories have spaces in it (remember this 
script is also used on Windows):

   $ test `echo foo bar` != `echo foo bar`
   bash: test: too many arguments

Unfortunately, "`...`" is unportable if the substituted command also 
have quotes.  But a=`foo` does not break words so you can do this, which 
may also be marginally more readable:

   abs_top_builddir=`cd "${top_builddir}"; pwd`
   abs_top_srcdir=`cd "@top_srcdir@"; pwd`
   if test "$abs_top_builddir" != "$abs_top_srcdir"; then
     ...

Paolo