gem install fails with Rust 1.75.0

[moliver-hemasystems]

Describe the bug

We had some team members report issues when installing wasmer on MacOS with rustc 1.75.0 and Ruby 3.2.2. I was able to reproduce when I upgraded my rustc to 1.75.0, but when returning to 1.73.0 (which is what I was on prior), installation worked.

Steps to reproduce

1. install v1.75.0 of rustc
2. attempt to install the gem

Expected behavior

I'd expect the gem to compile and install successfully.

Actual behavior

When attempting to install with rustc 1.75.0, we get the following:

  Compiling wasmer v1.0.0 (/Users/{user}/.rbenv/versions/3.2.2/lib/ruby/gems/3.2.0/gems/wasmer-1.0.0/crates/wasmer)
error: unused import: `ClassInfo`
--> crates/wasmer/src/prelude.rs:3:62
  |
3 | pub use rutie_derive::{rubyclass, rubyfunction, rubymethods, ClassInfo, UpcastRubyClass};
  |                                                              ^^^^^^^^^
  |
note: the lint level is defined here
--> crates/wasmer/src/lib.rs:1:9
  |
1 | #![deny(warnings)]
  |         ^^^^^^^^
  = note: `#[deny(unused_imports)]` implied by `#[deny(warnings)]`


error: could not compile `wasmer` (lib) due to previous error
rake aborted!

[kingdonb]

FWIW to follow this report, I tried building the crate that's packed in the gem at Rust 1.74.1 and it worked, with this warning:

warning: the following packages contain code that will be rejected by a future version of Rust: cranelift-codegen-meta v0.74.0, wasmparser v0.78.2, wasmparser v0.79.0
note: to see what the problems were, use the option `--future-incompat-report`, or run `cargo report future-incompatibilities --id 1`

I'd guess that if I follow the advice it gives there, I'd be seeing in the output somewhere a similar warning to the one posted in the top-level reply.