dnl Available from the GNU Autoconf Macro Archive at:
dnl http://www.gnu.org/software/ac-archive/htmldoc/ac_c_long_long.html
dnl
AC_DEFUN([AC_C_LONG_LONG],
[AC_CACHE_CHECK(for long long int, ac_cv_c_long_long,
[if test "$GCC" = yes; then
  ac_cv_c_long_long=yes
  else
        AC_TRY_COMPILE(,[long long int i;],
   ac_cv_c_long_long=yes,
   ac_cv_c_long_long=no)
   fi])
   if test $ac_cv_c_long_long = yes; then
     AC_DEFINE(HAVE_LONG_LONG, 1, [Defined if the compiler supports long long int])
   fi
])