#![feature(effects)] causes ICE

[peter-lyons-kehl]

Long story: I'm rebasing my fork of Rust, mostly modified in library/alloc and library/core in 2023. I'm rebasing it on around 1 month old Rust master: 152a4e9. (I will re-base on the current master, I'll re-run and update here.)

My added/modified library/core code uses #[const_trait]. So I've added #![feature(effects)] to library/core/src/lib.rs. Then the attached ICE happens.

(The actual fork of Rust is out of scope here, but FYI https://github.com/coop-rs/rust/wiki https://github.com/coop-rs/rust - not on master, but being developed on https://github.com/coop-rs/rust/tree/07_vec_macroed_squash_fmt_workaround - but that is not the branch that triggers this).

UPDATE: My actual branch that triggers this ICE is: https://github.com/coop-rs/rust/tree/07_vec_macroed_squash_fmt_workaround_old_master_ice.

rustc-ice-2023-12-05T01:17:14.315936466Z-111587.txt

[peter-lyons-kehl]

UPDATE: My actual branch that triggers this ICE is: https://github.com/coop-rs/rust/tree/07_vec_macroed_squash_fmt_workaround_old_master_ice.

[peter-lyons-kehl]

UPDATE: Still an ICE (I did not check if the exact same ICE or not) with whatever bootstrap comes on Dec 4, 2023, for this fork based on that same day's master da1da3f.

If I remove #![feature(effects)] from library/core/src/lib.rs, the ICE does go away (even though then there is a normal compiler error).

UPDATE: The fork code (being built) that still triggers the ICE with today's master is https://github.com/coop-rs/rust/tree/07_vec_macroed_squash_fmt_workaround_ICE_Dec-04-2023.

rustc-ice-2023-12-05T02_18_48-128485.txt

[fee1-dead]

Dupe of #117004