Type incorrectly inferred for negative integer that is inferred as an usize

[pvginkel]

The output of the following test case is 18446744073709551615:

fn main() {
    let mut x = -1;

    for i in vec![1usize] {
        break;
        x = i;
    }

    println!("{}", x);
}

The problem is that x is inferred as being usize. However, the -1 initial value cannot be hold in that type, so it overflows/gets transmuted into an usize.

My expectation is that this should result in a compilation error.

Meta

rustc 1.1.0-beta (cd7d89a 2015-05-16) (built 2015-05-16)
binary: rustc
commit-hash: cd7d89a
commit-date: 2015-05-16
build-date: 2015-05-16
host: x86_64-pc-windows-gnu
release: 1.1.0-beta

[nagisa]

Same thing as #24676.

[alexcrichton]

Indeed, closing as a dupe.