acinclude.m4

        { return arg1 + arg2 + arg3; }
        int fun2(int arg1, int arg2)
        { return arg1 + arg2; }
      ],[
        int res3 = gcc_vmacro3(1, 2, 3);
        int res2 = gcc_vmacro2(1, 2);
      ])
    ],[
      curl_cv_variadic_macros_gcc="yes"
    ],[
      curl_cv_variadic_macros_gcc="no"
    ])
  ])
  case "$curl_cv_variadic_macros_gcc" in
    yes)
      AC_DEFINE_UNQUOTED(HAVE_VARIADIC_MACROS_GCC, 1,
        [Define to 1 if compiler supports old gcc variadic macro style.])
      ;;
  esac
])