IN: benchmark.fib6 USING: math kernel alien ; : fib ( x -- y ) "int" { "int" } "cdecl" [ dup 1 <= [ drop 1 ] [ 1- dup fib swap 1- fib + ] if ] alien-callback "int" { "int" } "cdecl" alien-indirect ; : fib-main ( -- ) 34 fib drop ; MAIN: fib-main