Compiler hangs checking recursive LazyCell with generic lifetime

Code

use std::cell::LazyCell;

enum Cycle<'c, F> {
    There(Box<Cycle<'c, F>>),
    Later(Box<LazyCell<Cycle<'c, F>, F>>),
}

trait Recursive<'c>: FnOnce() -> Cycle<'c, Self> + Sized {}

impl<'c, F> Recursive<'c> for F where F: FnOnce() -> Cycle<'c, F> {}

fn recursive<'c>() -> Cycle<'c, impl Recursive<'c>> {
    let make = || Cycle::There(Box::new(recursive()));
    Cycle::Later(LazyCell::new(make))
}

Meta

rustc --version --verbose before updating:

rustc 1.87.0 (17067e9ac 2025-05-09)
binary: rustc
commit-hash: 17067e9ac6d7ecb70e50f92c1944e545188d2359
commit-date: 2025-05-09
host: x86_64-unknown-linux-gnu
release: 1.87.0
LLVM version: 20.1.1

rustc --version --verbose after updating, yielding the same behaviour:

rustc 1.93.1 (01f6ddf75 2026-02-11)
binary: rustc
commit-hash: 01f6ddf7588f42ae2d7eb0a2f21d44e8e96674cf
commit-date: 2026-02-11
host: x86_64-unknown-linux-gnu
release: 1.93.1
LLVM version: 21.1.8

Error output

cargo check does not terminate.

Start by compiling the Rust reproducer with cargo check and confirm that it does not terminate. Investigate the compiler path involved in checking the recursive LazyCell and generic lifetime example; done means cargo check terminates with appropriate compiler behavior instead of hanging.