ICE on trait method with type parameter bounded by trait with lifetime parameter

[dwrensha]

I think this relates to #12807 and #5121.

The following program causes rustc to crash:

// lifetimes_bug.rs
use std;

pub struct StructReader<'a> {
    marker : std::kinds::marker::ContravariantLifetime<'a>,
}

pub trait FromStructReader<'a> {
    fn new(struct_reader : StructReader<'a>) -> Self;
}

pub trait MessageReader {
    fn get_root<'a, T :FromStructReader<'a>>(&'a self) -> T;
}

pub fn main () {}

$ rustc lifetimes_bug.rs 
error: internal compiler error: No inferred index entry for unknown node (id=31)

[dwrensha]

cc @pnkfelix

[Kimundi]

Another testcase:

trait RefIterable<T> {
    fn refs<'a, Iter: Iterator<&'a T>>(&'a self) -> Iter;
}
fn main() {}

error: internal compiler error: No inferred index entry for unknown node (id=18)
note: the compiler hit an unexpected failure path. this is a bug.
note: we would appreciate a bug report: http://static.rust-lang.org/doc/master/complement-bugreport.html
note: run with `RUST_BACKTRACE=1` for a backtrace
task 'rustc' failed at '~Any', /build/rust-git/src/rust/src/libsyntax/diagnostic.rs:123

[nikomatsakis]

cc me

[dwrensha]

Thanks for fixing!

As far as I know, now #12857 is the only thing preventing capnproto-rust from having a safe interface.