panic at Unrecognized literal

[alexanderkjall]

Hi, I'm going over all the dependencies in my dependency-tree with a fuzzer, and found this panic in syn:

thread 'main' panicked at 'Unrecognized literal: 6E--5458', /home/capitol/.cargo/registry/src/github.com-1ecc6299db9ec823/syn-1.0.41/src/lit.rs:955:13

It can be reproduced with this program:

use syn::Expr;

fn main() {
    let s = "6E--5458";
    let _ = syn::parse_str::<Expr>(s);
}

I would have expected it to return an Error instead.

[dtolnay]

Thank you! I've published syn 1.0.42 with a fix. This issue involved some bugs in proc-macro2 as well so you'll need to update both.