Converting self-recursive arrays to string overflows the call stack

JavaScript, in its infinite wisdom, allows us to have arrays that contains themselves. For obvious reasons, trying to convert such an array to a string is not a good idea, but QV4 right now does not handle this case very nicely - in fact, the call stack overflows and the engine crashes.

let v1 = [];
v1.push(v1);
console.log(v1); // Crashes

There is some room for debate as to what the "correct" handling of this case should be (or indeed if this should be specified at all); for example, here is js60:

js> let v1 = [];
js> v1.push(v1);
1
js> console.log(v1);

js>

Incidentally, Python has a similar construct; it appears to generally use ... to notate the self-referencing members of an array.