Doug Kaufman corrected my attempt to a generic "skip extra test for function

[],

dnl if not found, $ac_func is the name we check for

func="$ac_func"

if test "skipcheck_$func" != "yes"; then

eval skipcheck=\$skipcheck_$func

if test "x$skipcheck" != "xyes"; then

  AC_MSG_CHECKING([deeper for $func])

  AC_TRY_LINK( [],

               [ $func ();],