Make recursing too deep a fatal runtime error and make the limit larger

[brson]

What we are doing now leaks (#3555) and I don't know how to fix it yet, so we should not pretend we can enforce stack size limits safely.

[eholk]

Hmm... limits on recursion depth make me cringe.

Why have stack limits at all if we can just keep growing the stack?

[brson]

As a sanity check. Eating all your ram and having the machine lock up while it swaps and oom kills is no fun. Nobody means to recurse infinitely.

[brson]

FWIW I tested infinite recursion on Go over the weekend and let the process grow to over 1GB before I killed it manually. Not sure if they just recurse forever or not.

[DonMartio]

Disregarding the risk of being off topic. Are there any plans implementing tail recursion?

[catamorphism]

@DonMartio - We're not sure yet; see #217.

[brson]

gcc's __morestack calls abort if allocation fails

[nikomatsakis]

Not critical for 0.6; removing milestone

[catamorphism]

Nominating for milestone 5, production-ready