Undefined nested associated type causes ICE

[solson]

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trait Trait {
    fn foo();
}

fn main() {
    <<i32 as Copy>::foobar as Trait>::foo();
    // In general, <<Type as AnyTraitTheTypeImplements>::anything as AnyTrait>::method();
}

The above causes the following the following error:

<anon>:6:6: 6:27 error: internal compiler error: Cannot project an associated type from `VtableBuiltin(nested=[[];[];[]])`
<anon>:6     <<i32 as Copy>::foobar as Trait>::foo();
              ^~~~~~~~~~~~~~~~~~~~~
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: http://doc.rust-lang.org/complement-bugreport.html
note: run with `RUST_BACKTRACE=1` for a backtrace
thread 'rustc' panicked at 'Box<Any>', /home/rustbuild/src/rust-buildbot/slave/nightly-dist-rustc-linux/build/src/libsyntax/diagnostic.rs:129

It works correctly if foobar is actually a defined associated type.