ICE during orphanck with the next solver involving opaque type "covered" by a fundamental type

[fmease]

Reproducer

a.rs: rustc a.rs --crate-type=lib:

#![feature(fundamental)]

pub trait Trait {}

#[fundamental]
pub struct Wrap<T>(pub T);

b.rs: rustc b.rs --crate-type=lib --extern a -L. --edition=2021 -Znext-solver:

#![feature(type_alias_impl_trait)]

type Opaque = a::Wrap<impl Sized>;

fn define() -> Opaque { a::Wrap(()) }

impl a::Trait for Opaque {}

Compiler Output

Compiler output (includes backtrace)

thread 'rustc' panicked at compiler/rustc_hir_analysis/src/coherence/orphan.rs:481:22:
called `Option::unwrap()` on a `None` value
stack backtrace:
   0:     0x72865b08ea90 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::h2f23fd9f9d9d249c
   1:     0x72865b814f26 - core::fmt::write::hda581013c22cc38e
   2:     0x72865c778bd1 - std::io::Write::write_fmt::h7b67a2c48701ad74
   3:     0x72865b08e8f2 - std::sys::backtrace::BacktraceLock::print::hf557d5f06e408e4b
   4:     0x72865b090d72 - std::panicking::default_hook::{{closure}}::h003adb2133b1767b
   5:     0x72865b090bfa - std::panicking::default_hook::h16009a902eb48a3c
   6:     0x72865a242759 - std[b112ec976dab40f4]::panicking::update_hook::<alloc[fdb5804898039ca3]::boxed::Box<rustc_driver_impl[8694186ee707eb2f]::install_ice_hook::{closure#1}>>::{closure#0}
   7:     0x72865b0918f3 - std::panicking::rust_panic_with_hook::h1d06543d16cce998
   8:     0x72865b0915b6 - std::panicking::begin_panic_handler::{{closure}}::h5b7fe21fdd65a607
   9:     0x72865b08ef79 - std::sys::backtrace::__rust_end_short_backtrace::hddbdfb95dc40ef8a
  10:     0x72865b0912ad - rust_begin_unwind
  11:     0x728657d961e0 - core::panicking::panic_fmt::h94f5d8fdec5491a8
  12:     0x72865881f19c - core::panicking::panic::hdce3ddcf69ca9a10
  13:     0x7286592923c9 - core::option::unwrap_failed::h27f2e94e7dd4b9a4
  14:     0x728658fdf279 - rustc_hir_analysis[13152efa0adca590]::coherence::orphan::orphan_check_impl
  15:     0x72865be835a5 - rustc_query_impl[1da25cef12df1694]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[1da25cef12df1694]::query_impl::orphan_check_impl::dynamic_query::{closure#2}::{closure#0}, rustc_middle[a35b023f906b1e15]::query::erase::Erased<[u8; 1usize]>>
  16:     0x72865be83907 - rustc_query_system[35b3a8f846374855]::query::plumbing::try_execute_query::<rustc_query_impl[1da25cef12df1694]::DynamicConfig<rustc_data_structures[eb304daffe7c7b80]::vec_cache::VecCache<rustc_span[863c7cf5cfba53d9]::def_id::LocalDefId, rustc_middle[a35b023f906b1e15]::query::erase::Erased<[u8; 1usize]>, rustc_query_system[35b3a8f846374855]::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl[1da25cef12df1694]::plumbing::QueryCtxt, false>
  17:     0x72865be83334 - rustc_query_impl[1da25cef12df1694]::query_impl::orphan_check_impl::get_query_non_incr::__rust_end_short_backtrace
  18:     0x72865bf6004c - rustc_hir_analysis[13152efa0adca590]::coherence::coherent_trait
  19:     0x72865bf5f577 - rustc_query_impl[1da25cef12df1694]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[1da25cef12df1694]::query_impl::coherent_trait::dynamic_query::{closure#2}::{closure#0}, rustc_middle[a35b023f906b1e15]::query::erase::Erased<[u8; 1usize]>>
  20:     0x72865bb2ebef - rustc_query_system[35b3a8f846374855]::query::plumbing::try_execute_query::<rustc_query_impl[1da25cef12df1694]::DynamicConfig<rustc_query_system[35b3a8f846374855]::query::caches::DefIdCache<rustc_middle[a35b023f906b1e15]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[1da25cef12df1694]::plumbing::QueryCtxt, false>
  21:     0x72865bb2dc22 - rustc_query_impl[1da25cef12df1694]::query_impl::coherent_trait::get_query_non_incr::__rust_end_short_backtrace
  22:     0x72865be85b5e - rustc_hir_analysis[13152efa0adca590]::check::wfcheck::check_well_formed
  23:     0x72865be84147 - rustc_query_impl[1da25cef12df1694]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[1da25cef12df1694]::query_impl::check_well_formed::dynamic_query::{closure#2}::{closure#0}, rustc_middle[a35b023f906b1e15]::query::erase::Erased<[u8; 1usize]>>
  24:     0x72865be83be9 - rustc_query_system[35b3a8f846374855]::query::plumbing::try_execute_query::<rustc_query_impl[1da25cef12df1694]::DynamicConfig<rustc_data_structures[eb304daffe7c7b80]::vec_cache::VecCache<rustc_span[863c7cf5cfba53d9]::def_id::LocalDefId, rustc_middle[a35b023f906b1e15]::query::erase::Erased<[u8; 1usize]>, rustc_query_system[35b3a8f846374855]::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl[1da25cef12df1694]::plumbing::QueryCtxt, false>
  25:     0x72865be83646 - rustc_query_impl[1da25cef12df1694]::query_impl::check_well_formed::get_query_non_incr::__rust_end_short_backtrace
  26:     0x72865be8126c - rustc_hir_analysis[13152efa0adca590]::check::wfcheck::check_mod_type_wf
  27:     0x72865be8108b - rustc_query_impl[1da25cef12df1694]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[1da25cef12df1694]::query_impl::check_mod_type_wf::dynamic_query::{closure#2}::{closure#0}, rustc_middle[a35b023f906b1e15]::query::erase::Erased<[u8; 1usize]>>
  28:     0x72865c77d3c8 - rustc_query_system[35b3a8f846374855]::query::plumbing::try_execute_query::<rustc_query_impl[1da25cef12df1694]::DynamicConfig<rustc_query_system[35b3a8f846374855]::query::caches::DefaultCache<rustc_span[863c7cf5cfba53d9]::def_id::LocalModDefId, rustc_middle[a35b023f906b1e15]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[1da25cef12df1694]::plumbing::QueryCtxt, false>
  29:     0x72865c77d170 - rustc_query_impl[1da25cef12df1694]::query_impl::check_mod_type_wf::get_query_non_incr::__rust_end_short_backtrace
  30:     0x72865bb82ce6 - rustc_hir_analysis[13152efa0adca590]::check_crate
  31:     0x72865bb7f5a2 - rustc_interface[7b6200b50ffd4527]::passes::run_required_analyses
  32:     0x72865c7742de - rustc_interface[7b6200b50ffd4527]::passes::analysis
  33:     0x72865c7742af - rustc_query_impl[1da25cef12df1694]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[1da25cef12df1694]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[a35b023f906b1e15]::query::erase::Erased<[u8; 0usize]>>
  34:     0x72865c75bbd5 - rustc_query_system[35b3a8f846374855]::query::plumbing::try_execute_query::<rustc_query_impl[1da25cef12df1694]::DynamicConfig<rustc_query_system[35b3a8f846374855]::query::caches::SingleCache<rustc_middle[a35b023f906b1e15]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[1da25cef12df1694]::plumbing::QueryCtxt, false>
  35:     0x72865c75b90e - rustc_query_impl[1da25cef12df1694]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  36:     0x72865c788a29 - rustc_interface[7b6200b50ffd4527]::passes::create_and_enter_global_ctxt::<core[1c802f461cf195ce]::option::Option<rustc_interface[7b6200b50ffd4527]::queries::Linker>, rustc_driver_impl[8694186ee707eb2f]::run_compiler::{closure#0}::{closure#2}>::{closure#2}::{closure#0}
  37:     0x72865c7c3dd3 - rustc_interface[7b6200b50ffd4527]::interface::run_compiler::<(), rustc_driver_impl[8694186ee707eb2f]::run_compiler::{closure#0}>::{closure#1}
  38:     0x72865c6857f5 - std[b112ec976dab40f4]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[7b6200b50ffd4527]::util::run_in_thread_with_globals<rustc_interface[7b6200b50ffd4527]::util::run_in_thread_pool_with_globals<rustc_interface[7b6200b50ffd4527]::interface::run_compiler<(), rustc_driver_impl[8694186ee707eb2f]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
  39:     0x72865c6854d9 - <<std[b112ec976dab40f4]::thread::Builder>::spawn_unchecked_<rustc_interface[7b6200b50ffd4527]::util::run_in_thread_with_globals<rustc_interface[7b6200b50ffd4527]::util::run_in_thread_pool_with_globals<rustc_interface[7b6200b50ffd4527]::interface::run_compiler<(), rustc_driver_impl[8694186ee707eb2f]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[1c802f461cf195ce]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  40:     0x72865c684c6f - std::sys::pal::unix::thread::Thread::new::thread_start::hf2e53aa54a2bf93d
  41:     0x728656aa339d - <unknown>
  42:     0x728656b2849c - <unknown>
  43:                0x0 - <unknown>

error: 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: please make sure that you have updated to the latest nightly

note: rustc 1.86.0-nightly (1e9b0177d 2025-01-24) running on x86_64-unknown-linux-gnu

note: compiler flags: --crate-type lib -Z next-solver

query stack during panic:
#0 [orphan_check_impl] checking whether impl `<impl at b.rs:8:1: 8:62>` follows the orphan rules
#1 [coherent_trait] coherence checking all impls of trait `a::Trait`
... and 3 other queries... use `env RUST_BACKTRACE=1` to see the full query stack

Meta

I semi-knowingly introduced this bug in #117164, see FIXMEs (I just didn't have any reproducers (this likely isn't the only one)).

[fmease]

Right, by using stdlib items we can shorten this to:

rustc file.rs --crate-type=lib -Znext-solver

#![feature(type_alias_impl_trait)]

type Opaque = Box<impl Sized>;

fn define() -> Opaque { Box::new(()) }

impl Copy for Opaque {}

(Box is #[fundamental] and non-local, Copy is non-local)