Code does not compile due to ignored trait implementation

A recent update of wide broke (https://github.com/Lokathor/wide/issues/303#issuecomment-5141894529) some code that compiled before.

The latest version (1.6.0) changes the way traits are implemented for SIMD types, and reduces to the following code that should work but instead gives a compile error:

use std::ops::Add;

pub struct Type;

impl Add for Type {
    type Output = Self;

    fn add(self, _: Type) -> Self::Output {
        unimplemented!()
    }
}

impl<Rhs> Add<&Rhs> for Type
where
    Self: Add<Rhs, Output = Self>,
{
    type Output = Self;

    fn add(self, _: &Rhs) -> Self::Output {
        unimplemented!()
    }
}

trait T<'s> {}
fn test<'s>(_x: impl T<'s>) {
    let _ = Type + Type;
}

I expected to see this happen: Code compiles.

Instead, it does not compile and gives this error:

> cargo check
    Checking tt v0.1.0 (/tmp/philae/tt)
error[E0275]: overflow evaluating the requirement `Type: Add<&_>`
   ╭▸ src/lib.rs:26:18
   │
26 │     let _ = Type + Type;
   │                  ━
   │
   ╰ help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`tt`)
note: required for `Type` to implement `Add<&&_>`
   ╭▸ src/lib.rs:13:11
   │
13 │ impl<Rhs> Add<&Rhs> for Type
   │           ━━━━━━━━━     ━━━━
14 │ where
15 │     Self: Add<Rhs, Output = Self>,
   │                    ───────────── unsatisfied trait bound introduced here
   ├ note: 126 redundant requirements hidden
   ├ note: required for `Type` to implement `Add<&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&_>`
   ├ note: the full name for the type has been written to '/tmp/philae/tt/target/debug/deps/tt-d36a269beefb58bc.long-type-7391855843772083704.txt'
   ╰ note: consider using `--verbose` to print the full type name to the console

For more information about this error, try `rustc --explain E0275`.
error: could not compile `tt` (lib) due to 1 previous error

All of the changes below make the code compile:

• Dropping the Add<&Rhs> trait implementation.
• Removing the unused _x argument.
• Changing the _x: impl T<'s> to _x: impl T<'static>.
• Removing the Output = Self bound in the implementation of Add<&Rhs>.
• Changing Rhs in impl<Rhs> Add<&Rhs> for Type to a specific type.

Meta

The bug is there both on (yesterdays) stable, nightly, and also those from ~2 months ago (the last time I ran rustup update before yesterday).

rustc 1.99.0-nightly (1a833e165 2026-07-29)
binary: rustc
commit-hash: 1a833e16546c2eb012758ddd499964fd8afee29e
commit-date: 2026-07-29
host: x86_64-unknown-linux-gnu
release: 1.99.0-nightly
LLVM version: 22.1.8

Start with the reduced Rust example in the issue and run cargo check to reproduce the E0275 overflow. Investigate the trait obligations created by the generic Add<&Rhs> implementation and lifetime parameter, then confirm the original example compiles without the listed workarounds and add a regression test where appropriate.