i64::MIN literal out of range warning

[mahkoh]

let x: i64 = -9223372036854775808;

warning: literal out of range for its type, #[warn(type_overflow)] on by default

[robertg]

I was investigating this, and somewhere along the linting it basically ends up being a node representing +9223372036854775808, which would clearly cause this warning message.

I will continue working on this.

[mahkoh]

I guess that's right. When you look at the rustc output you can see that only the digits but not the - are underlined.

[robertg]

So regarding the above, it actually wasn't the case where the AST was broken. It was rather that we weren't utilizing the propagated sign properly.