Method push on Vec struct

[abjrcode]

I started learning Rust recently and I was checking the source code for reference so bear with me please.
Isn't this a bug?
We are casting the length which is defined as usize to isize? if not why so?

[bluss]

Hi, it's complicated but it should be explained in this RFC's text: rust-lang/rfcs#1966

I'll close this issue, there are other forums for more ongoing discussion. Feel free to report more bugs here.