Polymorphic Recursion Causing Stack Overflow

[jozefg]

The following causes rustc to keel over

enum Tree<A> {
    Leaf(A),
    Node(Box<Tree<(A, A)>>)
}

fn size<A>(t : &Tree<A>) -> int {
    match t {
        &Leaf(_) => 1,
        &Node(box ref t) => size(t)
    }
}

fn main () {}

// task 'rustc' has overflowed its stack
// Compilation illegal instruction (core dumped) at Fri Nov 14 18:04:13

However it handles the actual declaration fine, the issue seems to be due to the polymorphic recursion in size. This compiles fine

enum Tree<A> {
    Leaf(A),
    Node(Box<Tree<(A, A)>>)
}

fn main () {}

My rustc information is

rustc 0.13.0-nightly (5745e4195 2014-11-12 22:57:16 +0000)
binary: rustc
commit-hash: 5745e419502d753deb3f42026fa35e015bc5d3fb
commit-date: 2014-11-12 22:57:16 +0000
host: x86_64-unknown-linux-gnu
release: 0.13.0-nightly

[huonw]

Dupe of #4363. Thanks for filing!