ICE When Building combine in DEBUG MODE (WITHOUT --release)

[HTGAzureX1212]

Code

/* this ICE lies in the combine crate */

Meta

rustc --version --verbose:

rustc 1.69.0-nightly (50d3ba5bc 2023-02-04)
binary: rustc
commit-hash: 50d3ba5bcbf5c7e13d4ce068d3339710701dd603
commit-date: 2023-02-04
host: x86_64-pc-windows-msvc
release: 1.69.0-nightly
LLVM version: 15.0.7

Error output

error: internal compiler error: no errors encountered even though `delay_span_bug` issued

error: internal compiler error: broken MIR in Item(WithOptConstParam { did: DefId(0:3569 ~ combine[b357]::stream::{impl#47}::reset), const_param_did: None }) (after phase change to runtime-optimized) at bb0[2]:
                                encountered `Assign((_0, const Result::<(), StringStreamError>::Ok(())))` with incompatible types:
                                left-hand side has type: Result<(), <&str as StreamOnce>::Error>
                                right-hand side has type: Result<(), StringStreamError>

Backtrace

error: internal compiler error: no errors encountered even though `delay_span_bug` issued

error: internal compiler error: broken MIR in Item(WithOptConstParam { did: DefId(0:3569 ~ combine[b357]::stream::{impl#47}::reset), const_param_did: None }) (after phase change to runtime-optimized) at bb0[2]:
                                encountered `Assign((_0, const Result::<(), StringStreamError>::Ok(())))` with incompatible types:
                                left-hand side has type: Result<(), <&str as StreamOnce>::Error>
                                right-hand side has type: Result<(), StringStreamError>
   --> C:\Users\USER\.cargo\registry\src\git.luolix.top-1ecc6299db9ec823\combine-4.6.6\src\stream\mod.rs:44:17
    |
44  |                 Ok(())
    |                 ^^^^^^
...
153 | clone_resetable! {('a) &'a str}
    | ------------------------------- in this macro invocation
    |
    = note: delayed at    0: std::backtrace::Backtrace::disabled
               1: std::backtrace::Backtrace::force_capture
               2: <rustc_errors::HandlerInner>::emit_diagnostic
               3: <rustc_const_eval::interpret::validity::PathElem as core::fmt::Debug>::fmt
               4: rustc_const_eval::transform::promote_consts::is_const_fn_in_array_repeat_expression
               5: <rustc_const_eval::transform::validate::Validator as rustc_middle::mir::MirPass>::run_pass
               6: <rustc_mir_transform::ctfe_limit::CtfeLimit as rustc_middle::mir::MirPass>::run_pass
               7: <rustc_mir_transform::unreachable_prop::UnreachablePropagation as rustc_middle::mir::MirPass>::run_pass
               8: <rustc_middle::ty::Visibility as rustc_privacy::VisibilityLike>::new_min
               9: <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::as_any
              10: <rustc_metadata::rmeta::encoder::EncodeContext as rustc_type_ir::codec::TyEncoder>::position
              11: rustc_metadata::rmeta::encoder::encode_metadata
              12: <rustc_metadata::rmeta::LazyTables as rustc_serialize::serialize::Decodable<rustc_metadata::rmeta::decoder::DecodeContext>>::decode
              13: rustc_metadata::rmeta::encoder::encode_metadata
              14: rustc_metadata::fs::encode_and_write_metadata
              15: rustc_interface::passes::start_codegen
              16: rustc_interface::passes::output_filenames
              17: <rustc_interface::queries::Queries>::ongoing_codegen
              18: rustc_driver_impl::args::arg_expand_all
              19: <rustc_data_structures::temp_dir::MaybeTempDir>::new
              20: rustc_driver_impl::args::arg_expand_all
              21: <rustc_data_structures::temp_dir::MaybeTempDir>::new
              22: <rustc_data_structures::temp_dir::MaybeTempDir>::new
              23: std::sys::windows::thread::Thread::new
              24: BaseThreadInitThunk
              25: RtlUserThreadStart

    = note: this error: internal compiler error originates in the macro `clone_resetable` (in Nightly builds, run with -Z macro-backtrace for more info)

note: the compiler unexpectedly panicked. this is a bug.

note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: rustc 1.69.0-nightly (50d3ba5bc 2023-02-04) running on x86_64-pc-windows-msvc

note: compiler flags: --crate-type lib -C embed-bitcode=no -C debuginfo=2 -C target-cpu=native

note: some of the compiler flags provided by cargo are hidden

query stack during panic:
end of query stack

[HTGAzureX1212]

Compilation works fine when building WITH --release.

[lukas-code]

searched nightlies: from nightly-2023-02-03 to nightly-2023-02-05
regressed nightly: nightly-2023-02-05
searched commit range: 658fad6...50d3ba5
regressed commit: 9dee4e4 (#107267)

bisected with cargo-bisect-rustc v0.6.5

Host triple: x86_64-unknown-linux-gnu
Reproduce with:

cargo bisect-rustc --regress=ice -- build 

[lukas-code]

reduced example:

#![crate_type = "lib"]

pub trait StreamOnce {
    type Error;
}

pub trait ResetStream: StreamOnce {
    fn reset(&mut self) -> Result<(), Self::Error>;
}

impl<'a> ResetStream for &'a str
    where Self: StreamOnce
{
    #[inline]
    fn reset(&mut self) -> Result<(), Self::Error> {
        Ok(())
    }
}

// impl<T> StreamOnce for T {
//     type Error = ();
// }

Building a library and the inline attribute are required to reproduce.

This example will also ICE on stable, but if you uncomment the last three lines it only ICEs on nighly. So #107267 probably only revealed this bug and isn't the root cause of it.

@rustbot label S-bug-has-mcve

[lqd]

@rustbot label regression-from-stable-to-nightly

[Bjohnson131]

I'm also seeing this. in nightly 2/7/23 back until at least 1/1/23. This date is a mistake. My bad.

[JakobDegen]

cc either @oli-obk or @lcnr , this seems to be some weirdness in the handling of trivially false bounds (at least the stable variant, the nightly one might be a different root cause)

Edit: Oh, I didn't see that there was a fix up already

[NobodyXu]

This ICE also happens on target x86_64-unknown-linux-gnu in cargo-bins/cargo-binstall#773 , however on target x86_64-pc-windows-msvc it did not occur.