rust-lang / rust-lang/rust

[ICE]: `variable in universe U0 can't name value in universe U1`

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C-bug F-non_lifetime_binders I-ICE requires-debug-assertions T-compiler WG-trait-system-refactor
Dominant language
Rust
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Description

auto-reduced (treereduce-rust):

//@compile-flags: -Znext-solver=globally
#![feature(non_lifetime_binders)]
trait Foo {
    type Bar;
}
fn f<T1>()
where
    T1: for<T> Foo<Bar = T>,
{
    f();
}

original:

#![feature(non_lifetime_binders)]
trait Foo { type Bar; }
fn f<T1>()
where
    T1: for<T> Foo<Bar = T>{
    f();
}

fn main() {}

Version information

rustc 1.99.0-nightly (da86f4d07 2026-07-24)
binary: rustc
commit-hash: da86f4d0726be475afbbffe40cb2f65741c51ad3
commit-date: 2026-07-24
host: x86_64-unknown-linux-gnu
release: 1.99.0-nightly
LLVM version: 22.1.8

Possibly related line of code:
https://github.com/rust-lang/rust/blob/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_infer/src/infer/context.rs#L443-L455

Command:
/home/matthias/.rustup/toolchains/alt-master/bin/rustc -Znext-solver=globally

Program output 

warning: the feature `non_lifetime_binders` is incomplete and may not be safe to use and/or cause compiler crashes
 --> /tmp/icemaker_global_tempdir.X8GbpKMVvL2x/rustc_testrunner_tmpdir_reporting.iq02Su7FE8Em/mvce.rs:1:12
  |
1 | #![feature(non_lifetime_binders)]
  |            ^^^^^^^^^^^^^^^^^^^^
  |
  = note: see issue #108185 <https://github.com/rust-lang/rust/issues/108185> for more information
  = note: `#[warn(incomplete_features)]` on by default

error[E0601]: `main` function not found in crate `mvce`
  --> /tmp/icemaker_global_tempdir.X8GbpKMVvL2x/rustc_testrunner_tmpdir_reporting.iq02Su7FE8Em/mvce.rs:10:2
   |
10 | }
   |  ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.X8GbpKMVvL2x/rustc_testrunner_tmpdir_reporting.iq02Su7FE8Em/mvce.rs`


thread 'rustc' (1913052) panicked at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_infer/src/infer/context.rs:449:9:
variable in universe U0 can't name value in universe U1
stack backtrace:
   0:     0x7f7effc07180 - std[4957aea88bdd0f88]::backtrace_rs::backtrace::libunwind::trace
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/../../backtrace/src/backtrace/libunwind.rs:117:9
   1:     0x7f7effc07180 - std[4957aea88bdd0f88]::backtrace_rs::backtrace::trace_unsynchronized::<std[4957aea88bdd0f88]::sys::backtrace::_print_fmt::{closure#1}>
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/../../backtrace/src/backtrace/mod.rs:66:14
   2:     0x7f7effc07180 - std[4957aea88bdd0f88]::sys::backtrace::_print_fmt
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/sys/backtrace.rs:74:9
   3:     0x7f7effc07180 - <<std[4957aea88bdd0f88]::sys::backtrace::BacktraceLock>::print::DisplayBacktrace as core[da6cea203c5b5d33]::fmt::Display>::fmt
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/sys/backtrace.rs:44:26
   4:     0x7f7efb495afe - <core[da6cea203c5b5d33]::fmt::rt::Argument>::fmt
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/fmt/rt.rs:152:76
   5:     0x7f7efb495afe - core[da6cea203c5b5d33]::fmt::write
   6:     0x7f7effc1e11c - core[da6cea203c5b5d33]::io::write::default_write_fmt::<std[4957aea88bdd0f88]::sys::stdio::unix::Stderr>
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/io/write.rs:402:11
   7:     0x7f7effc1e11c - <std[4957aea88bdd0f88]::sys::stdio::unix::Stderr as core[da6cea203c5b5d33]::io::write::Write>::write_fmt
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/io/write.rs:335:13
   8:     0x7f7effbc6544 - <std[4957aea88bdd0f88]::sys::backtrace::BacktraceLock>::print
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/sys/backtrace.rs:47:9
   9:     0x7f7effbc6544 - std[4957aea88bdd0f88]::panicking::default_hook::{closure#0}
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:292:27
  10:     0x7f7effbf37e1 - std[4957aea88bdd0f88]::panicking::default_hook
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:319:9
  11:     0x7f7efc7b9738 - <alloc[741620e15a3c417e]::boxed::Box<dyn for<'a, 'b> core[da6cea203c5b5d33]::ops::function::Fn<(&'a std[4957aea88bdd0f88]::panic::PanicHookInfo<'b>,), Output = ()> + core[da6cea203c5b5d33]::marker::Sync + core[da6cea203c5b5d33]::marker::Send> as core[da6cea203c5b5d33]::ops::function::Fn<(&std[4957aea88bdd0f88]::panic::PanicHookInfo,)>>::call
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/alloc/src/boxed.rs:2340:9
  12:     0x7f7efc7b9738 - rustc_driver_impl[cb05b4e96be3d0e4]::install_ice_hook::{closure#1}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_driver_impl/src/lib.rs:1482:17
  13:     0x7f7efc7b9738 - <alloc[741620e15a3c417e]::boxed::Box<rustc_driver_impl[cb05b4e96be3d0e4]::install_ice_hook::{closure#1}> as core[da6cea203c5b5d33]::ops::function::Fn<(&dyn for<'a, 'b> core[da6cea203c5b5d33]::ops::function::Fn<(&'a std[4957aea88bdd0f88]::panic::PanicHookInfo<'b>,), Output = ()> + core[da6cea203c5b5d33]::marker::Sync + core[da6cea203c5b5d33]::marker::Send, &std[4957aea88bdd0f88]::panic::PanicHookInfo)>>::call
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/alloc/src/boxed.rs:2340:9
  14:     0x7f7efc7b9738 - std[4957aea88bdd0f88]::panicking::update_hook::<alloc[741620e15a3c417e]::boxed::Box<rustc_driver_impl[cb05b4e96be3d0e4]::install_ice_hook::{closure#1}>>::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:235:47
  15:     0x7f7effbf3c6a - <alloc[741620e15a3c417e]::boxed::Box<dyn for<'a, 'b> core[da6cea203c5b5d33]::ops::function::Fn<(&'a std[4957aea88bdd0f88]::panic::PanicHookInfo<'b>,), Output = ()> + core[da6cea203c5b5d33]::marker::Sync + core[da6cea203c5b5d33]::marker::Send> as core[da6cea203c5b5d33]::ops::function::Fn<(&std[4957aea88bdd0f88]::panic::PanicHookInfo,)>>::call
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/alloc/src/boxed.rs:2340:9
  16:     0x7f7effbf3c6a - std[4957aea88bdd0f88]::panicking::panic_with_hook
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:823:13
  17:     0x7f7effbc6612 - std[4957aea88bdd0f88]::panicking::panic_handler::{closure#0}
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:688:13
  18:     0x7f7effbb6919 - std[4957aea88bdd0f88]::sys::backtrace::__rust_end_short_backtrace::<std[4957aea88bdd0f88]::panicking::panic_handler::{closure#0}, !>
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/sys/backtrace.rs:182:18
  19:     0x7f7effbc850d - __rustc[b6a9bdc199f3cce9]::rust_begin_unwind
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:679:5
  20:     0x7f7efb49684c - core[da6cea203c5b5d33]::panicking::panic_fmt
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/panicking.rs:80:14
  21:     0x7f7efd4a3298 - rustc_infer[a44cb6b08f431519]::infer::context::lower_universe::<rustc_middle[66530f1cd38cda85]::ty::Ty>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_infer/src/infer/context.rs:449:9
  22:     0x7f7efd4a3298 - <rustc_infer[a44cb6b08f431519]::infer::InferCtxt as rustc_type_ir[a2ec8591d3d5b635]::infer_ctxt::InferCtxtLike>::instantiate_ty_var_raw
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_infer/src/infer/context.rs:258:18
  23:     0x7f7eff7fd03c - <rustc_next_trait_solver[ff5a353b4b6e8b97]::canonical::ResponseRelating<rustc_infer[a44cb6b08f431519]::infer::InferCtxt, rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt> as rustc_type_ir[a2ec8591d3d5b635]::relate::TypeRelation<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>::tys
  24:     0x7f7eff4fc2b7 - <rustc_middle[66530f1cd38cda85]::ty::Ty as rustc_type_ir[a2ec8591d3d5b635]::relate::Relate<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>::relate::<rustc_next_trait_solver[ff5a353b4b6e8b97]::canonical::ResponseRelating<rustc_infer[a44cb6b08f431519]::infer::InferCtxt, rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_middle/src/ty/relate.rs:17:18
  25:     0x7f7eff4fc2b7 - <rustc_next_trait_solver[ff5a353b4b6e8b97]::canonical::ResponseRelating<rustc_infer[a44cb6b08f431519]::infer::InferCtxt, rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt> as rustc_type_ir[a2ec8591d3d5b635]::relate::TypeRelation<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>::relate::<rustc_middle[66530f1cd38cda85]::ty::Ty>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_type_ir/src/relate.rs:61:9
  26:     0x7f7eff4fc2b7 - <rustc_middle[66530f1cd38cda85]::ty::generic_args::GenericArg as rustc_type_ir[a2ec8591d3d5b635]::relate::Relate<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>::relate::<rustc_next_trait_solver[ff5a353b4b6e8b97]::canonical::ResponseRelating<rustc_infer[a44cb6b08f431519]::infer::InferCtxt, rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_middle/src/ty/relate.rs:147:29
  27:     0x7f7eff47b4c3 - <rustc_next_trait_solver[ff5a353b4b6e8b97]::canonical::ResponseRelating<rustc_infer[a44cb6b08f431519]::infer::InferCtxt, rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt> as rustc_type_ir[a2ec8591d3d5b635]::relate::TypeRelation<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>::relate::<rustc_middle[66530f1cd38cda85]::ty::generic_args::GenericArg>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_type_ir/src/relate.rs:61:9
  28:     0x7f7eff47b4c3 - rustc_next_trait_solver[ff5a353b4b6e8b97]::canonical::unify_query_var_values::<rustc_trait_selection[54401a8eb81d4c3d]::solve::delegate::SolverDelegate, rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_next_trait_solver/src/canonical/mod.rs:471:17
  29:     0x7f7eff47c1ad - rustc_next_trait_solver[ff5a353b4b6e8b97]::canonical::instantiate_canonical_state::<rustc_trait_selection[54401a8eb81d4c3d]::solve::delegate::SolverDelegate, rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt, ()>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_next_trait_solver/src/canonical/mod.rs:568:5
  30:     0x7f7eff64b20d - <rustc_trait_selection[54401a8eb81d4c3d]::solve::inspect::analyse::InspectCandidate>::instantiate_nested_goals
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_trait_selection/src/solve/inspect/analyse.rs:114:13
  31:     0x7f7eff8d5987 - <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::derive_errors::BestObligation as rustc_trait_selection[54401a8eb81d4c3d]::solve::inspect::analyse::ProofTreeVisitor>::visit_goal
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_trait_selection/src/solve/fulfill/derive_errors.rs:473:38
  32:     0x7f7eff4f22ff - <rustc_infer[a44cb6b08f431519]::infer::InferCtxt as rustc_trait_selection[54401a8eb81d4c3d]::solve::inspect::analyse::InferCtxtProofTreeExt>::visit_proof_tree_at_depth::<rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::derive_errors::BestObligation>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_trait_selection/src/solve/inspect/analyse.rs:386:17
  33:     0x7f7eff797c5c - <rustc_infer[a44cb6b08f431519]::infer::InferCtxt as rustc_trait_selection[54401a8eb81d4c3d]::solve::inspect::analyse::InferCtxtProofTreeExt>::visit_proof_tree::<rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::derive_errors::BestObligation>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_trait_selection/src/solve/inspect/analyse.rs:375:14
  34:     0x7f7eff797c5c - rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::derive_errors::find_best_leaf_obligation::{closure#0}::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_trait_selection/src/solve/fulfill/derive_errors.rs:174:18
  35:     0x7f7eff797c5c - <rustc_infer[a44cb6b08f431519]::infer::InferCtxt>::fudge_inference_if_ok::<(rustc_middle[66530f1cd38cda85]::traits::ObligationCause, rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>), (), rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::derive_errors::find_best_leaf_obligation::{closure#0}::{closure#0}>::{closure#0}::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_infer/src/infer/snapshot/fudge.rs:107:25
  36:     0x7f7eff797c5c - <rustc_infer[a44cb6b08f431519]::infer::InferCtxt>::probe::<core[da6cea203c5b5d33]::result::Result<(rustc_infer[a44cb6b08f431519]::infer::snapshot::fudge::SnapshotVarData, (rustc_middle[66530f1cd38cda85]::traits::ObligationCause, rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>)), ()>, <rustc_infer[a44cb6b08f431519]::infer::InferCtxt>::fudge_inference_if_ok<(rustc_middle[66530f1cd38cda85]::traits::ObligationCause, rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>), (), rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::derive_errors::find_best_leaf_obligation::{closure#0}::{closure#0}>::{closure#0}::{closure#0}>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_infer/src/infer/snapshot/mod.rs:106:17
  37:     0x7f7eff797c5c - <rustc_infer[a44cb6b08f431519]::infer::InferCtxt>::fudge_inference_if_ok::<(rustc_middle[66530f1cd38cda85]::traits::ObligationCause, rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>), (), rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::derive_errors::find_best_leaf_obligation::{closure#0}::{closure#0}>::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_infer/src/infer/snapshot/fudge.rs:106:43
  38:     0x7f7eff797c5c - <rustc_infer[a44cb6b08f431519]::infer::InferCtxt>::fudge_inference_if_ok::<(rustc_middle[66530f1cd38cda85]::traits::ObligationCause, rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>), (), rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::derive_errors::find_best_leaf_obligation::{closure#0}::{closure#0}>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_infer/src/infer/snapshot/fudge.rs:98:5
  39:     0x7f7eff797c5c - rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::derive_errors::find_best_leaf_obligation::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_trait_selection/src/solve/fulfill/derive_errors.rs:172:10
  40:     0x7f7eff797c5c - rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::derive_errors::find_best_leaf_obligation
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_trait_selection/src/solve/fulfill/derive_errors.rs:159:1
  41:     0x7f7eff7ff709 - rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::derive_errors::fulfillment_error_for_stalled
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_trait_selection/src/solve/fulfill/derive_errors.rs:139:13
  42:     0x7f7eff7ff709 - <rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError as rustc_infer[a44cb6b08f431519]::traits::engine::FromSolverError<rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::NextSolverError>>::from_solver_error
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_trait_selection/src/solve/fulfill.rs:382:17
  43:     0x7f7efd22952c - <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#2}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_trait_selection/src/solve/fulfill.rs:196:22
  44:     0x7f7efd22952c - <&mut <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#2} as core[da6cea203c5b5d33]::ops::function::FnOnce<(rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::NextSolverError,)>>::call_once
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/ops/function.rs:310:21
  45:     0x7f7efd22952c - <core[da6cea203c5b5d33]::option::Option<rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::NextSolverError>>::map::<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError, &mut <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#2}>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/option.rs:1163:29
  46:     0x7f7efd22952c - <core[da6cea203c5b5d33]::iter::adapters::map::Map<core[da6cea203c5b5d33]::iter::adapters::chain::Chain<core[da6cea203c5b5d33]::iter::adapters::map::Map<thin_vec[93149897e20cd01b]::Drain<(rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>, core[da6cea203c5b5d33]::option::Option<rustc_type_ir[a2ec8591d3d5b635]::solve::GoalStalledOn<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>)>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#0}>, core[da6cea203c5b5d33]::iter::adapters::map::Map<alloc[741620e15a3c417e]::vec::drain::Drain<rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#1}>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#2}> as core[da6cea203c5b5d33]::iter::traits::iterator::Iterator>::next
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/iter/adapters/map.rs:107:26
  47:     0x7f7efd21e0e0 - <alloc[741620e15a3c417e]::vec::Vec<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::extend_desugared::<core[da6cea203c5b5d33]::iter::adapters::map::Map<core[da6cea203c5b5d33]::iter::adapters::chain::Chain<core[da6cea203c5b5d33]::iter::adapters::map::Map<thin_vec[93149897e20cd01b]::Drain<(rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>, core[da6cea203c5b5d33]::option::Option<rustc_type_ir[a2ec8591d3d5b635]::solve::GoalStalledOn<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>)>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#0}>, core[da6cea203c5b5d33]::iter::adapters::map::Map<alloc[741620e15a3c417e]::vec::drain::Drain<rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#1}>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#2}>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/alloc/src/vec/mod.rs:4105:44
  48:     0x7f7efd21e0e0 - <alloc[741620e15a3c417e]::vec::Vec<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as alloc[741620e15a3c417e]::vec::spec_extend::SpecExtend<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError, core[da6cea203c5b5d33]::iter::adapters::map::Map<core[da6cea203c5b5d33]::iter::adapters::chain::Chain<core[da6cea203c5b5d33]::iter::adapters::map::Map<thin_vec[93149897e20cd01b]::Drain<(rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>, core[da6cea203c5b5d33]::option::Option<rustc_type_ir[a2ec8591d3d5b635]::solve::GoalStalledOn<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>)>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#0}>, core[da6cea203c5b5d33]::iter::adapters::map::Map<alloc[741620e15a3c417e]::vec::drain::Drain<rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#1}>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#2}>>>::spec_extend
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/alloc/src/vec/spec_extend.rs:18:14
  49:     0x7f7efd21e0e0 - <alloc[741620e15a3c417e]::vec::Vec<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as alloc[741620e15a3c417e]::vec::spec_from_iter_nested::SpecFromIterNested<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError, core[da6cea203c5b5d33]::iter::adapters::map::Map<core[da6cea203c5b5d33]::iter::adapters::chain::Chain<core[da6cea203c5b5d33]::iter::adapters::map::Map<thin_vec[93149897e20cd01b]::Drain<(rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>, core[da6cea203c5b5d33]::option::Option<rustc_type_ir[a2ec8591d3d5b635]::solve::GoalStalledOn<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>)>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#0}>, core[da6cea203c5b5d33]::iter::adapters::map::Map<alloc[741620e15a3c417e]::vec::drain::Drain<rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#1}>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#2}>>>::from_iter
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/alloc/src/vec/spec_from_iter_nested.rs:41:9
  50:     0x7f7efd21e0e0 - <alloc[741620e15a3c417e]::vec::Vec<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as alloc[741620e15a3c417e]::vec::spec_from_iter::SpecFromIter<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError, core[da6cea203c5b5d33]::iter::adapters::map::Map<core[da6cea203c5b5d33]::iter::adapters::chain::Chain<core[da6cea203c5b5d33]::iter::adapters::map::Map<thin_vec[93149897e20cd01b]::Drain<(rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>, core[da6cea203c5b5d33]::option::Option<rustc_type_ir[a2ec8591d3d5b635]::solve::GoalStalledOn<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>)>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#0}>, core[da6cea203c5b5d33]::iter::adapters::map::Map<alloc[741620e15a3c417e]::vec::drain::Drain<rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#1}>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#2}>>>::from_iter
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/alloc/src/vec/spec_from_iter.rs:33:9
  51:     0x7f7efd21e0e0 - <alloc[741620e15a3c417e]::vec::Vec<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as core[da6cea203c5b5d33]::iter::traits::collect::FromIterator<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::from_iter::<core[da6cea203c5b5d33]::iter::adapters::map::Map<core[da6cea203c5b5d33]::iter::adapters::chain::Chain<core[da6cea203c5b5d33]::iter::adapters::map::Map<thin_vec[93149897e20cd01b]::Drain<(rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>, core[da6cea203c5b5d33]::option::Option<rustc_type_ir[a2ec8591d3d5b635]::solve::GoalStalledOn<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>)>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#0}>, core[da6cea203c5b5d33]::iter::adapters::map::Map<alloc[741620e15a3c417e]::vec::drain::Drain<rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#1}>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#2}>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/alloc/src/vec/mod.rs:4001:9
  52:     0x7f7efd21e0e0 - <core[da6cea203c5b5d33]::iter::adapters::map::Map<core[da6cea203c5b5d33]::iter::adapters::chain::Chain<core[da6cea203c5b5d33]::iter::adapters::map::Map<thin_vec[93149897e20cd01b]::Drain<(rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>, core[da6cea203c5b5d33]::option::Option<rustc_type_ir[a2ec8591d3d5b635]::solve::GoalStalledOn<rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>>)>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#0}>, core[da6cea203c5b5d33]::iter::adapters::map::Map<alloc[741620e15a3c417e]::vec::drain::Drain<rustc_infer[a44cb6b08f431519]::traits::Obligation<rustc_middle[66530f1cd38cda85]::ty::predicate::Predicate>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#1}>>, <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors::{closure#2}> as core[da6cea203c5b5d33]::iter::traits::iterator::Iterator>::collect::<alloc[741620e15a3c417e]::vec::Vec<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/iter/traits/iterator.rs:2090:9
  53:     0x7f7efd21e0e0 - <rustc_trait_selection[54401a8eb81d4c3d]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError> as rustc_infer[a44cb6b08f431519]::traits::engine::TraitEngine<rustc_trait_selection[54401a8eb81d4c3d]::traits::FulfillmentError>>::collect_remaining_errors
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_trait_selection/src/solve/fulfill.rs:197:14
  54:     0x7f7efd03998b - <rustc_hir_typeck[58a2748dd8480fc]::fn_ctxt::FnCtxt>::report_ambiguity_errors
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs:722:59
  55:     0x7f7efd03998b - rustc_hir_typeck[58a2748dd8480fc]::typeck_with_inspect::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_hir_typeck/src/lib.rs:267:13
  56:     0x7f7efd05fef8 - rustc_hir_typeck[58a2748dd8480fc]::typeck_with_inspect
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_hir_typeck/src/lib.rs:110:1
  57:     0x7f7efeb63c87 - rustc_query_impl[caac36dfda81a9d7]::query_impl::typeck_root::invoke_provider_fn::__rust_begin_short_backtrace
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_query_impl/src/query_impl.rs:118:46
  58:     0x7f7efe902115 - rustc_query_impl[caac36dfda81a9d7]::execution::execute_job_non_incr::<rustc_data_structures[8b14e35dea0ad776]::vec_cache::VecCache<rustc_span[de76fed82ebe26ff]::def_id::LocalDefId, rustc_middle[66530f1cd38cda85]::query::erase::ErasedData<[u8; 8usize]>, rustc_middle[66530f1cd38cda85]::dep_graph::graph::DepNodeIndex>>::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_query_impl/src/execution.rs:422:59
  59:     0x7f7efe902115 - rustc_middle[66530f1cd38cda85]::ty::context::tls::enter_context::<rustc_query_impl[caac36dfda81a9d7]::execution::execute_job_non_incr<rustc_data_structures[8b14e35dea0ad776]::vec_cache::VecCache<rustc_span[de76fed82ebe26ff]::def_id::LocalDefId, rustc_middle[66530f1cd38cda85]::query::erase::ErasedData<[u8; 8usize]>, rustc_middle[66530f1cd38cda85]::dep_graph::graph::DepNodeIndex>>::{closure#0}, rustc_middle[66530f1cd38cda85]::query::erase::ErasedData<[u8; 8usize]>>::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_middle/src/ty/context/tls.rs:56:9
 

< snip>

 109:     0x7f7efec0fd41 - stacker[63f11707587470ee]::maybe_grow::<rustc_middle[66530f1cd38cda85]::query::erase::ErasedData<[u8; 0usize]>, rustc_query_impl[caac36dfda81a9d7]::execution::execute_query_non_incr_inner<rustc_middle[66530f1cd38cda85]::query::caches::SingleCache<rustc_middle[66530f1cd38cda85]::query::erase::ErasedData<[u8; 0usize]>>>::{closure#0}>
                               at /rust/deps/stacker-0.1.21/src/lib.rs:57:9
 110:     0x7f7efec0fd41 - rustc_data_structures[8b14e35dea0ad776]::stack::ensure_sufficient_stack::<rustc_middle[66530f1cd38cda85]::query::erase::ErasedData<[u8; 0usize]>, rustc_query_impl[caac36dfda81a9d7]::execution::execute_query_non_incr_inner<rustc_middle[66530f1cd38cda85]::query::caches::SingleCache<rustc_middle[66530f1cd38cda85]::query::erase::ErasedData<[u8; 0usize]>>>::{closure#0}>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_data_structures/src/stack.rs:21:5
 111:     0x7f7efec0fd41 - rustc_query_impl[caac36dfda81a9d7]::execution::execute_query_non_incr_inner::<rustc_middle[66530f1cd38cda85]::query::caches::SingleCache<rustc_middle[66530f1cd38cda85]::query::erase::ErasedData<[u8; 0usize]>>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_query_impl/src/execution.rs:616:5
 112:     0x7f7efec0fd41 - rustc_query_impl[caac36dfda81a9d7]::query_impl::analysis::execute_query_non_incr::__rust_end_short_backtrace
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_query_impl/src/query_impl.rs:82:30
 113:     0x7f7efc744a9f - rustc_middle[66530f1cd38cda85]::query::inner::query_ensure_ok::<rustc_middle[66530f1cd38cda85]::query::caches::SingleCache<rustc_middle[66530f1cd38cda85]::query::erase::ErasedData<[u8; 0usize]>>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_middle/src/query/inner.rs:61:13
 114:     0x7f7efc744a9f - <rustc_middle[66530f1cd38cda85]::query::plumbing::TyCtxtEnsureOk>::analysis
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_middle/src/query/plumbing.rs:579:21
 115:     0x7f7efc744a9f - rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_driver_impl/src/lib.rs:314:29
 116:     0x7f7efc744a9f - rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt::<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_interface/src/passes.rs:1035:80
 117:     0x7f7efc744a9f - <core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}::{closure#0}> as core[da6cea203c5b5d33]::ops::function::FnOnce<()>>::call_once
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/panic/unwind_safe.rs:275:9
 118:     0x7f7efc744a9f - std[4957aea88bdd0f88]::panicking::catch_unwind::do_call::<core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}::{closure#0}>, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:576:43
 119:     0x7f7efc744a9f - std[4957aea88bdd0f88]::panicking::catch_unwind::<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}::{closure#0}>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:544:19
 120:     0x7f7efc744a9f - std[4957aea88bdd0f88]::panic::catch_unwind::<core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}::{closure#0}>, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panic.rs:359:14
 121:     0x7f7efc744a9f - rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt::<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_interface/src/passes.rs:1035:23
 122:     0x7f7efc744a9f - <rustc_middle[66530f1cd38cda85]::ty::context::GlobalCtxt>::enter::<rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>::{closure#1}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_middle/src/ty/context.rs:792:37
 123:     0x7f7efc744a9f - rustc_middle[66530f1cd38cda85]::ty::context::tls::enter_context::<<rustc_middle[66530f1cd38cda85]::ty::context::GlobalCtxt>::enter<rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>::{closure#1}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_middle/src/ty/context/tls.rs:56:9
 124:     0x7f7efc744a9f - <std[4957aea88bdd0f88]::thread::local::LocalKey<core[da6cea203c5b5d33]::cell::Cell<*const ()>>>::try_with::<rustc_middle[66530f1cd38cda85]::ty::context::tls::enter_context<<rustc_middle[66530f1cd38cda85]::ty::context::GlobalCtxt>::enter<rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>::{closure#1}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>::{closure#0}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/thread/local.rs:464:12
 125:     0x7f7efc744a9f - <std[4957aea88bdd0f88]::thread::local::LocalKey<core[da6cea203c5b5d33]::cell::Cell<*const ()>>>::with::<rustc_middle[66530f1cd38cda85]::ty::context::tls::enter_context<<rustc_middle[66530f1cd38cda85]::ty::context::GlobalCtxt>::enter<rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>::{closure#1}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>::{closure#0}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/thread/local.rs:428:20
 126:     0x7f7efc744a9f - rustc_middle[66530f1cd38cda85]::ty::context::tls::enter_context::<<rustc_middle[66530f1cd38cda85]::ty::context::GlobalCtxt>::enter<rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>::{closure#1}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_middle/src/ty/context/tls.rs:53:9
 127:     0x7f7efc744a9f - <rustc_middle[66530f1cd38cda85]::ty::context::GlobalCtxt>::enter::<rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}, core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_middle/src/ty/context.rs:792:9
 128:     0x7f7efc744a9f - <rustc_middle[66530f1cd38cda85]::ty::context::TyCtxt>::create_global_ctxt::<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>::{closure#2}>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_middle/src/ty/context.rs:983:13
 129:     0x7f7efc744a9f - rustc_interface[b0e8760c305ddcff]::passes::create_and_enter_global_ctxt::<core[da6cea203c5b5d33]::option::Option<rustc_interface[b0e8760c305ddcff]::queries::Linker>, rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}::{closure#1}>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_interface/src/passes.rs:996:5
 130:     0x7f7efc7bdb18 - rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_driver_impl/src/lib.rs:292:22
 131:     0x7f7efc7bdb18 - rustc_interface[b0e8760c305ddcff]::interface::run_compiler::<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_interface/src/interface.rs:486:80
 132:     0x7f7efc7bdb18 - <core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}::{closure#0}> as core[da6cea203c5b5d33]::ops::function::FnOnce<()>>::call_once
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/panic/unwind_safe.rs:275:9
 133:     0x7f7efc7bdb18 - std[4957aea88bdd0f88]::panicking::catch_unwind::do_call::<core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}::{closure#0}>, ()>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:576:43
 134:     0x7f7efc7bdb18 - std[4957aea88bdd0f88]::panicking::catch_unwind::<(), core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}::{closure#0}>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:544:19
 135:     0x7f7efc7bdb18 - std[4957aea88bdd0f88]::panic::catch_unwind::<core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}::{closure#0}>, ()>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panic.rs:359:14
 136:     0x7f7efc7bdb18 - rustc_interface[b0e8760c305ddcff]::interface::run_compiler::<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_interface/src/interface.rs:486:23
 137:     0x7f7efc7a71fb - rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals::<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_interface/src/util.rs:203:17
 138:     0x7f7efc7a71fb - rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals::<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_interface/src/util.rs:162:24
 139:     0x7f7efc7a71fb - <scoped_tls[e3fb68ce1c3f569d]::ScopedKey<rustc_span[de76fed82ebe26ff]::SessionGlobals>>::set::<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}::{closure#0}, ()>
                               at /rust/deps/scoped-tls-1.0.1/src/lib.rs:137:9
 140:     0x7f7efc7a71fb - rustc_span[de76fed82ebe26ff]::create_session_globals_then::<(), rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}::{closure#0}>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_span/src/lib.rs:155:21
 141:     0x7f7efc7a71fb - rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals::<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/compiler/rustc_interface/src/util.rs:158:17
 142:     0x7f7efc7a71fb - std[4957aea88bdd0f88]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/sys/backtrace.rs:166:18
 143:     0x7f7efc7c1d09 - std[4957aea88bdd0f88]::thread::lifecycle::spawn_unchecked::<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1}::{closure#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/thread/lifecycle.rs:70:13
 144:     0x7f7efc7c1d09 - <core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<std[4957aea88bdd0f88]::thread::lifecycle::spawn_unchecked<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1}::{closure#0}> as core[da6cea203c5b5d33]::ops::function::FnOnce<()>>::call_once
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/panic/unwind_safe.rs:275:9
 145:     0x7f7efc7c1d09 - std[4957aea88bdd0f88]::panicking::catch_unwind::do_call::<core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<std[4957aea88bdd0f88]::thread::lifecycle::spawn_unchecked<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1}::{closure#0}>, ()>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:576:43
 146:     0x7f7efc7c1d09 - std[4957aea88bdd0f88]::panicking::catch_unwind::<(), core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<std[4957aea88bdd0f88]::thread::lifecycle::spawn_unchecked<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1}::{closure#0}>>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panicking.rs:544:19
 147:     0x7f7efc7c1d09 - std[4957aea88bdd0f88]::panic::catch_unwind::<core[da6cea203c5b5d33]::panic::unwind_safe::AssertUnwindSafe<std[4957aea88bdd0f88]::thread::lifecycle::spawn_unchecked<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1}::{closure#0}>, ()>
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/panic.rs:359:14
 148:     0x7f7efc7c1d09 - std[4957aea88bdd0f88]::thread::lifecycle::spawn_unchecked::<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/thread/lifecycle.rs:68:26
 149:     0x7f7efc7c1d09 - <std[4957aea88bdd0f88]::thread::lifecycle::spawn_unchecked<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_with_globals<rustc_interface[b0e8760c305ddcff]::util::run_in_thread_pool_with_globals<rustc_interface[b0e8760c305ddcff]::interface::run_compiler<(), rustc_driver_impl[cb05b4e96be3d0e4]::run_compiler::{closure#0}>::{closure#2}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[da6cea203c5b5d33]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
                               at /rustc-dev/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/core/src/ops/function.rs:250:5
 150:     0x7f7effc02cef - <alloc[741620e15a3c417e]::boxed::Box<dyn core[da6cea203c5b5d33]::ops::function::FnOnce<(), Output = ()> + core[da6cea203c5b5d33]::marker::Send> as core[da6cea203c5b5d33]::ops::function::FnOnce<()>>::call_once
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/alloc/src/boxed.rs:2326:9
 151:     0x7f7effc02cef - <std[4957aea88bdd0f88]::sys::thread::unix::Thread>::new::thread_start
                               at /rustc/da86f4d0726be475afbbffe40cb2f65741c51ad3/library/std/src/sys/thread/unix.rs:123:17
 152:     0x7f7ef9a97739 - <unknown>
 153:     0x7f7ef9b1bedc - <unknown>
 154:                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 1.99.0-nightly (da86f4d07 2026-07-24) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z next-solver=globally -Z dump-mir-dir=dir

query stack during panic:
#0 [typeck_root] type-checking `f`
#1 [analysis] running analysis passes on crate `mvce`
end of query stack
error: aborting due to 1 previous error; 1 warning emitted

For more information about this error, try `rustc --explain E0601`.

@rustbot label +F-non_lifetime_binders +WG-trait-system-refactor

Contributor guide

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First steps

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Research direction

Start with the reduced reproducer in the issue using rustc -Znext-solver=globally, then inspect compiler/rustc_infer/src/infer/context.rs:443-455 and the lower_universe and instantiate_ty_var_raw stack frames. Trace how the higher-universe associated type is related; done means the reproducer no longer causes the compiler ICE and the behavior is covered by a regression test.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
compilers
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Quiet
Clarity
Needs clarification
Newbie friendliness
42/100

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