Inferred types cause awful error messages

[jdm]

trait T {
    fn foo();
}

fn bar<V: T>(v: @V) {
    v.foo();
}

fn main() {
    bar(5);
}

/tmp/typecheck.rs:10:8: 10:9 error: mismatched types: expected `@<V0>` but found `<VI0>` (expected @-ptr but found integral variable)
/tmp/typecheck.rs:10     bar(5);
                             ^
/tmp/typecheck.rs:10:4: 10:7 error: cannot determine a type for this bounded type parameter: unconstrained type
/tmp/typecheck.rs:10     bar(5);
                         ^~~

[catamorphism]

Seems non-critical for 0.7. Nominating for milestone 5 (production-ready).

[graydon]

accepted for production ready

[bstrie]

More-or-less a dupe of #3723, adding this test case to that one and closing.

[bblum]

thanks for triaging for me @bstrie