Something

AC_MSG_CHECKING(whether to use system-wide highscores)
AC_ARG_ENABLE(highscore-dir,
AC_HELP_STRING([--enable-highscore-dir=DIR], [system-wide highscore table @<:@default=no@:>@]), [use_highscore_dir=yes], [use_highscore_dir=no])

if test "$use_highscore_dir" = "no"; then
  AC_MSG_RESULT(no)
  AC_SUBST(HIGHSCORE_DIRECTORY, "")
else
  AC_MSG_RESULT($enableval)
  AC_DEFINE_UNQUOTED(HIGHSCORE_DIRECTORY, "$enableval", [The system-wide highscore directory])
  AC_SUBST(HIGHSCORE_DIRECTORY, $enableval)
fi