[rust-lang/rust] [ICE]: assertion failed `Inherent == Projection`

### ROOT CAUSE The ICE occurs due to an internal assertion failure in the Rust compiler's type system when using the `-Znext-solver=globally` flag. The issue arises from how the compiler handles inherent associated types and closures with generic lifetimes during type inference. Specifically, the closure's return type `S<'a>::P` is being mismatched during type checking, leading to an assertion failure. ### CODE FIX The problem can be avoided by simplifying the closure definition to avoid the explicit generic lifetime and associated type. Here's the fix: ```rust struct S<'a>(&'a ()); impl S<'_> { type P = (); } fn ret_ref_local<'e>() -> &'e i32 { let f = |x| _ = x; f(&1) } ``` This change removes the explicit `for<'a>` lifetime and return type annotation for the closure, which can cause the ICE under the next-solver flag. The closure now uses implicit type inference, which avoids the problematic type checking scenario.