ICE: unexpected cyclic definition of Opaque::{opaque#0} #151301
Description
auto-reduced (treereduce-rust):
//@compile-flags: -Znext-solver=globally
#![feature(type_alias_impl_trait)]
fn id(s: &str) -> &str {
s
}
type Opaque<'a> = impl Sized + 'a;
#[define_opaque(Opaque)]
fn test(s: &str) -> (Opaque<'_>, impl Fn(&str) -> Opaque<'_>) {
(s, id)
}
fn main() {}original:
//! This test checks that when checking for opaque types that
//! only differ in lifetimes, we handle the case of non-generic
//! regions correctly.
#![feature(type_alias_impl_trait)]
fn id(s: &str) -> &str {
s
}
type Opaque<'a> = impl Sized + 'a;
// The second `Opaque<'_>` has a higher kinded lifetime, not a generic parameter
#[define_opaque(Opaque)]
fn test(s: &str) -> (Opaque<'_>, impl Fn(&str) -> Opaque<'_>) {
(s, id)
//~^ ERROR: expected generic lifetime parameter, found `'_`
}
fn main() {}Version information
rustc 1.95.0-nightly (621d76794 2026-01-18)
binary: rustc
commit-hash: 621d76794c76fc21c0a6151fbc090120e0230a91
commit-date: 2026-01-18
host: x86_64-unknown-linux-gnu
release: 1.95.0-nightly
LLVM version: 21.1.8
Command:
/home/matthias/.rustup/toolchains/master/bin/rustc -Znext-solver=globally
Program output
warning: function `id` is never used
--> /tmp/icemaker_global_tempdir.qPsSfphIpD9P/rustc_testrunner_tmpdir_reporting.OpLEcG0fUe3b/mvce.rs:3:4
|
3 | fn id(s: &str) -> &str {
| ^^
|
= note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
warning: type alias `Opaque` is never used
--> /tmp/icemaker_global_tempdir.qPsSfphIpD9P/rustc_testrunner_tmpdir_reporting.OpLEcG0fUe3b/mvce.rs:6:6
|
6 | type Opaque<'a> = impl Sized + 'a;
| ^^^^^^
warning: function `test` is never used
--> /tmp/icemaker_global_tempdir.qPsSfphIpD9P/rustc_testrunner_tmpdir_reporting.OpLEcG0fUe3b/mvce.rs:9:4
|
9 | fn test(s: &str) -> (Opaque<'_>, impl Fn(&str) -> Opaque<'_>) {
| ^^^^
warning: 3 warnings emitted
note: no errors encountered even though delayed bugs were created
note: those delayed bugs will now be shown as internal compiler errors
error: internal compiler error: unexpected cyclic definition of `Opaque::{opaque#0}`
--> /tmp/icemaker_global_tempdir.qPsSfphIpD9P/rustc_testrunner_tmpdir_reporting.OpLEcG0fUe3b/mvce.rs:9:63
|
9 | fn test(s: &str) -> (Opaque<'_>, impl Fn(&str) -> Opaque<'_>) {
| _______________________________________________________________^
10 | | (s, id)
11 | | }
| |_^
|
note: delayed at /rustc-dev/621d76794c76fc21c0a6151fbc090120e0230a91/compiler/rustc_hir_typeck/src/opaque_types.rs:265:24
0: <rustc_errors::DiagCtxtInner>::emit_diagnostic
1: <rustc_errors::DiagCtxtHandle>::emit_diagnostic
2: <rustc_span::ErrorGuaranteed as rustc_errors::diagnostic::EmissionGuarantee>::emit_producing_guarantee
3: <rustc_errors::DiagCtxtHandle>::span_delayed_bug::<rustc_span::span_encoding::Span, alloc::string::String>
4: rustc_hir_typeck::typeck_with_inspect::{closure#0}
5: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
6: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
7: rustc_query_impl::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
8: rustc_mir_build::thir::pattern::check_match::check_match
9: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_match::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
10: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 1]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
11: rustc_query_impl::query_impl::check_match::get_query_non_incr::__rust_end_short_backtrace
12: rustc_mir_build::builder::build_mir_inner_impl
13: rustc_mir_transform::mir_built
14: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_built::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
15: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
16: rustc_query_impl::query_impl::mir_built::get_query_non_incr::__rust_end_short_backtrace
17: rustc_mir_transform::ffi_unwind_calls::has_ffi_unwind_calls
18: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::has_ffi_unwind_calls::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
19: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 1]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
20: rustc_query_impl::query_impl::has_ffi_unwind_calls::get_query_non_incr::__rust_end_short_backtrace
21: rustc_mir_transform::mir_promoted
22: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_promoted::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 16]>>
23: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 16]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
24: rustc_query_impl::query_impl::mir_promoted::get_query_non_incr::__rust_end_short_backtrace
25: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_borrowck::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
26: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
27: rustc_query_impl::query_impl::mir_borrowck::get_query_non_incr::__rust_end_short_backtrace
28: <rustc_hir_analysis::collect::type_of::opaque::TaitConstraintLocator>::check
29: rustc_hir_analysis::collect::type_of::opaque::find_opaque_ty_constraints_for_tait
30: rustc_hir_analysis::collect::type_of::type_of_opaque.cold
31: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::type_of_opaque::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
32: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefIdCache<rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
33: rustc_query_impl::query_impl::type_of_opaque::get_query_non_incr::__rust_end_short_backtrace
34: rustc_hir_analysis::collect::type_of::type_of
35: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::type_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
36: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefIdCache<rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
37: rustc_query_impl::query_impl::type_of::get_query_non_incr::__rust_end_short_backtrace
38: rustc_hir_analysis::check::check::check_opaque
39: rustc_hir_analysis::check::check::check_item_type
40: rustc_hir_analysis::check::wfcheck::check_well_formed
41: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_well_formed::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
42: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 1]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
43: rustc_query_impl::query_impl::check_well_formed::get_query_non_incr::__rust_end_short_backtrace
44: rustc_hir_analysis::check::wfcheck::check_type_wf
45: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_type_wf::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
46: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 1]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
47: rustc_query_impl::query_impl::check_type_wf::get_query_non_incr::__rust_end_short_backtrace
48: rustc_hir_analysis::check_crate
49: rustc_interface::passes::analysis
50: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>
51: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 0]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
52: rustc_query_impl::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
53: <rustc_interface::passes::create_and_enter_global_ctxt<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>::{closure#2} as core::ops::function::FnOnce<(&rustc_session::session::Session, rustc_middle::ty::context::CurrentGcx, alloc::sync::Arc<rustc_data_structures::jobserver::Proxy>, &std::sync::once_lock::OnceLock<rustc_middle::ty::context::GlobalCtxt>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_middle::arena::Arena>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_hir::Arena>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2})>>::call_once::{shim:vtable#0}
54: rustc_interface::interface::run_compiler::<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}
55: std::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
56: <std::thread::lifecycle::spawn_unchecked<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
57: <std::sys::thread::unix::Thread>::new::thread_start
58: <unknown>
59: <unknown>
--> /tmp/icemaker_global_tempdir.qPsSfphIpD9P/rustc_testrunner_tmpdir_reporting.OpLEcG0fUe3b/mvce.rs:9:63
|
9 | fn test(s: &str) -> (Opaque<'_>, impl Fn(&str) -> Opaque<'_>) {
| _______________________________________________________________^
10 | | (s, id)
11 | | }
| |_^
error: internal compiler error: unexpected cyclic definition of `Opaque::{opaque#0}`
--> /tmp/icemaker_global_tempdir.qPsSfphIpD9P/rustc_testrunner_tmpdir_reporting.OpLEcG0fUe3b/mvce.rs:10:5
|
10 | (s, id)
| ^^^^^^^
|
note: delayed at /rustc-dev/621d76794c76fc21c0a6151fbc090120e0230a91/compiler/rustc_hir_typeck/src/opaque_types.rs:265:24
0: <rustc_errors::DiagCtxtInner>::emit_diagnostic
1: <rustc_errors::DiagCtxtHandle>::emit_diagnostic
2: <rustc_span::ErrorGuaranteed as rustc_errors::diagnostic::EmissionGuarantee>::emit_producing_guarantee
3: <rustc_errors::DiagCtxtHandle>::span_delayed_bug::<rustc_span::span_encoding::Span, alloc::string::String>
4: rustc_hir_typeck::typeck_with_inspect::{closure#0}
5: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
6: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
7: rustc_query_impl::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
8: rustc_mir_build::thir::pattern::check_match::check_match
9: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_match::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
10: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 1]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
11: rustc_query_impl::query_impl::check_match::get_query_non_incr::__rust_end_short_backtrace
12: rustc_mir_build::builder::build_mir_inner_impl
13: rustc_mir_transform::mir_built
14: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_built::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
15: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
16: rustc_query_impl::query_impl::mir_built::get_query_non_incr::__rust_end_short_backtrace
17: rustc_mir_transform::ffi_unwind_calls::has_ffi_unwind_calls
18: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::has_ffi_unwind_calls::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
19: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 1]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
20: rustc_query_impl::query_impl::has_ffi_unwind_calls::get_query_non_incr::__rust_end_short_backtrace
21: rustc_mir_transform::mir_promoted
22: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_promoted::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 16]>>
23: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 16]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
24: rustc_query_impl::query_impl::mir_promoted::get_query_non_incr::__rust_end_short_backtrace
25: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_borrowck::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
26: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
27: rustc_query_impl::query_impl::mir_borrowck::get_query_non_incr::__rust_end_short_backtrace
28: <rustc_hir_analysis::collect::type_of::opaque::TaitConstraintLocator>::check
29: rustc_hir_analysis::collect::type_of::opaque::find_opaque_ty_constraints_for_tait
30: rustc_hir_analysis::collect::type_of::type_of_opaque.cold
31: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::type_of_opaque::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
32: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefIdCache<rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
33: rustc_query_impl::query_impl::type_of_opaque::get_query_non_incr::__rust_end_short_backtrace
34: rustc_hir_analysis::collect::type_of::type_of
35: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::type_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
36: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefIdCache<rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
37: rustc_query_impl::query_impl::type_of::get_query_non_incr::__rust_end_short_backtrace
38: rustc_hir_analysis::check::check::check_opaque
39: rustc_hir_analysis::check::check::check_item_type
40: rustc_hir_analysis::check::wfcheck::check_well_formed
41: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_well_formed::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
42: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 1]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
43: rustc_query_impl::query_impl::check_well_formed::get_query_non_incr::__rust_end_short_backtrace
44: rustc_hir_analysis::check::wfcheck::check_type_wf
45: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_type_wf::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
46: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 1]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
47: rustc_query_impl::query_impl::check_type_wf::get_query_non_incr::__rust_end_short_backtrace
48: rustc_hir_analysis::check_crate
49: rustc_interface::passes::analysis
50: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>
51: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 0]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
52: rustc_query_impl::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
53: <rustc_interface::passes::create_and_enter_global_ctxt<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>::{closure#2} as core::ops::function::FnOnce<(&rustc_session::session::Session, rustc_middle::ty::context::CurrentGcx, alloc::sync::Arc<rustc_data_structures::jobserver::Proxy>, &std::sync::once_lock::OnceLock<rustc_middle::ty::context::GlobalCtxt>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_middle::arena::Arena>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_hir::Arena>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2})>>::call_once::{shim:vtable#0}
54: rustc_interface::interface::run_compiler::<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}
55: std::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
56: <std::thread::lifecycle::spawn_unchecked<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
57: <std::sys::thread::unix::Thread>::new::thread_start
58: <unknown>
59: <unknown>
--> /tmp/icemaker_global_tempdir.qPsSfphIpD9P/rustc_testrunner_tmpdir_reporting.OpLEcG0fUe3b/mvce.rs:10:5
|
10 | (s, id)
| ^^^^^^^
error: internal compiler error: unexpected cyclic definition of `Opaque::{opaque#0}`
--> /tmp/icemaker_global_tempdir.qPsSfphIpD9P/rustc_testrunner_tmpdir_reporting.OpLEcG0fUe3b/mvce.rs:9:1
|
9 | fn test(s: &str) -> (Opaque<'_>, impl Fn(&str) -> Opaque<'_>) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
note: delayed at /rustc-dev/621d76794c76fc21c0a6151fbc090120e0230a91/compiler/rustc_hir_typeck/src/opaque_types.rs:265:24
0: <rustc_errors::DiagCtxtInner>::emit_diagnostic
1: <rustc_errors::DiagCtxtHandle>::emit_diagnostic
2: <rustc_span::ErrorGuaranteed as rustc_errors::diagnostic::EmissionGuarantee>::emit_producing_guarantee
3: <rustc_errors::DiagCtxtHandle>::span_delayed_bug::<rustc_span::span_encoding::Span, alloc::string::String>
4: rustc_hir_typeck::typeck_with_inspect::{closure#0}
5: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
6: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
7: rustc_query_impl::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
8: rustc_mir_build::thir::pattern::check_match::check_match
9: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_match::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
10: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 1]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
11: rustc_query_impl::query_impl::check_match::get_query_non_incr::__rust_end_short_backtrace
12: rustc_mir_build::builder::build_mir_inner_impl
13: rustc_mir_transform::mir_built
14: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_built::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
15: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
16: rustc_query_impl::query_impl::mir_built::get_query_non_incr::__rust_end_short_backtrace
17: rustc_mir_transform::ffi_unwind_calls::has_ffi_unwind_calls
18: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::has_ffi_unwind_calls::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
19: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 1]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
20: rustc_query_impl::query_impl::has_ffi_unwind_calls::get_query_non_incr::__rust_end_short_backtrace
21: rustc_mir_transform::mir_promoted
22: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_promoted::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 16]>>
23: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 16]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
24: rustc_query_impl::query_impl::mir_promoted::get_query_non_incr::__rust_end_short_backtrace
25: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_borrowck::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
26: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
27: rustc_query_impl::query_impl::mir_borrowck::get_query_non_incr::__rust_end_short_backtrace
28: <rustc_hir_analysis::collect::type_of::opaque::TaitConstraintLocator>::check
29: rustc_hir_analysis::collect::type_of::opaque::find_opaque_ty_constraints_for_tait
30: rustc_hir_analysis::collect::type_of::type_of_opaque.cold
31: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::type_of_opaque::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
32: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefIdCache<rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
33: rustc_query_impl::query_impl::type_of_opaque::get_query_non_incr::__rust_end_short_backtrace
34: rustc_hir_analysis::collect::type_of::type_of
35: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::type_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
36: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefIdCache<rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
37: rustc_query_impl::query_impl::type_of::get_query_non_incr::__rust_end_short_backtrace
38: rustc_hir_analysis::check::check::check_opaque
39: rustc_hir_analysis::check::check::check_item_type
40: rustc_hir_analysis::check::wfcheck::check_well_formed
41: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_well_formed::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
42: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 1]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
43: rustc_query_impl::query_impl::check_well_formed::get_query_non_incr::__rust_end_short_backtrace
44: rustc_hir_analysis::check::wfcheck::check_type_wf
45: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_type_wf::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
46: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 1]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
47: rustc_query_impl::query_impl::check_type_wf::get_query_non_incr::__rust_end_short_backtrace
48: rustc_hir_analysis::check_crate
49: rustc_interface::passes::analysis
50: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>
51: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 0]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
52: rustc_query_impl::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
53: <rustc_interface::passes::create_and_enter_global_ctxt<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>::{closure#2} as core::ops::function::FnOnce<(&rustc_session::session::Session, rustc_middle::ty::context::CurrentGcx, alloc::sync::Arc<rustc_data_structures::jobserver::Proxy>, &std::sync::once_lock::OnceLock<rustc_middle::ty::context::GlobalCtxt>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_middle::arena::Arena>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_hir::Arena>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2})>>::call_once::{shim:vtable#0}
54: rustc_interface::interface::run_compiler::<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}
55: std::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
56: <std::thread::lifecycle::spawn_unchecked<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
57: <std::sys::thread::unix::Thread>::new::thread_start
58: <unknown>
59: <unknown>
--> /tmp/icemaker_global_tempdir.qPsSfphIpD9P/rustc_testrunner_tmpdir_reporting.OpLEcG0fUe3b/mvce.rs:9:1
|
9 | fn test(s: &str) -> (Opaque<'_>, impl Fn(&str) -> Opaque<'_>) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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 1.95.0-nightly (621d76794 2026-01-18) running on x86_64-unknown-linux-gnu
note: compiler flags: -Z next-solver=globally -Z dump-mir-dir=dir
query stack during panic:
end of query stack
@rustbot label +F-type_alias_impl_trait +WG-trait-system-refactor