nightly-2023-05-24 doesn't compile

[meowjesty]

Bug Description

Something changed between nightly-2023-03-29 (our current version) and nightly-2023-05-23 that breaks some of our const trait implementations.

If you try to cargo check with a newer version (the latest working I've tested was nightly-04-15, but I'm not sure if this is the last working one or something more recent also works) you'll get a #[const_trait] error.

Steps to Reproduce

1. Update rust-toolchain.toml to nightly-2023-05-23;
2. Run cargo check;
3. sadness;

Backtrace

error: const `impl` for trait `Default` which is not marked with `#[const_trait]`
   --> mirrord/layer/src/detour.rs:114:15
    |
114 | impl<T> const Default for HookFn<T> {
    |               ^^^^^^^
    |
    = note: marking a trait with `#[const_trait]` ensures all default method bodies are `const`
    = note: adding a non-const method body in the future would be a breaking change

Relevant Logs

No response

Your operating system and version

linux

Local process

NA

Local process version

No response

Additional Info

P.S. You'll probably get an error in the protocol/file.rs and not on the layer crate. In protocol the issue is easy to solve, we could just drop the const trait implementation, but in layer it requires bigger changes, due to HookFn expecting const stuff.

[meowjesty]

This broke our Default const implementations.

Workaround would be to have our own Default-like trait and implement it (and call the right function in the macros for HookFn).

[aviramha]

mm the default breakage makes me desiring of ?const idea