ICE: assoc-const-ty-mismatch.rs -Zsave-analysis: 'not yet implemented', compiler/rustc_infer/src/infer/at.rs

[matthiaskrgr]

Code

code reduced from ./src/test/ui/associated-consts/assoc-const-ty-mismatch.rs

#![feature(associated_const_equality)]
#![allow(unused)]

pub trait Foo {
  const N: usize;
}

pub struct Bar;

impl Foo for Bar {
  const N: usize = 3;
}


fn foo<F: Foo<N=usize>>() {}
//~^ ERROR mismatch in

fn main() {
  foo::<Bar>();
}

Meta

rustc --version --verbose:

rustc 1.60.0-nightly (1ea485171 2022-02-01)
binary: rustc
commit-hash: 1ea4851715893ee3f365a8ef09d47165e9a7864f
commit-date: 2022-02-01
host: x86_64-unknown-linux-gnu
release: 1.60.0-nightly
LLVM version: 13.0.0

(master toolchain)

Error output

rustc ./src/test/ui/associated-consts/assoc-const-ty-mismatch.rs -Zsave-analysis

error: mismatch in bind of associated constant, got type
  --> ./src/test/ui/associated-consts/assoc-const-ty-mismatch.rs:15:15
   |
15 | fn foo<F: Foo<N=usize>>() {}
   |               ^^^^^^^
   |
note: associated constant defined here does not match type
  --> ./src/test/ui/associated-consts/assoc-const-ty-mismatch.rs:5:3
   |
5  |   const N: usize;
   |   ^^^^^^^^^^^^^^^

thread 'rustc' panicked at 'not yet implemented', compiler/rustc_infer/src/infer/at.rs:304:23
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

error: internal compiler error: unexpected panic

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

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

note: rustc 1.60.0-nightly (1ea485171 2022-02-01) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z save-analysis

query stack during panic:
#0 [evaluate_obligation] evaluating trait selection obligation `<Bar as Foo>::N == usize`
#1 [typeck] type-checking `main`
end of query stack
error: aborting due to previous error

Backtrace

thread 'rustc' panicked at 'not yet implemented', compiler/rustc_infer/src/infer/at.rs:304:23
stack backtrace:
   0:     0x7fade2819c2c - std::backtrace_rs::backtrace::libunwind::trace::h97b555d93e806b9e
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7fade2819c2c - std::backtrace_rs::backtrace::trace_unsynchronized::hdaab24071cbd11d1
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7fade2819c2c - std::sys_common::backtrace::_print_fmt::hd526f02663d74738
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/sys_common/backtrace.rs:67:5
   3:     0x7fade2819c2c - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h8696deb8999a5f33
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/sys_common/backtrace.rs:46:22
   4:     0x7fade287b09c - core::fmt::write::h781fa008b8888eae
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/core/src/fmt/mod.rs:1190:17
   5:     0x7fade28091e3 - std::io::Write::write_fmt::h4ef48abde47b3baa
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/io/mod.rs:1653:15
   6:     0x7fade281e052 - std::sys_common::backtrace::_print::hcd70c906367332f8
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/sys_common/backtrace.rs:49:5
   7:     0x7fade281e052 - std::sys_common::backtrace::print::hdfafa975cab291c8
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/sys_common/backtrace.rs:36:9
   8:     0x7fade281e052 - std::panicking::default_hook::{{closure}}::hcc77563b35700099
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/panicking.rs:290:50
   9:     0x7fade281dc35 - std::panicking::default_hook::h988215e4515b4e8c
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/panicking.rs:307:9
  10:     0x7fade2ffd571 - rustc_driver[b8c5cee21782833e]::DEFAULT_HOOK::{closure#0}::{closure#0}
  11:     0x7fade281e86b - std::panicking::rust_panic_with_hook::ha5380a958bb71ca0
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/panicking.rs:695:17
  12:     0x7fade281e4e9 - std::panicking::begin_panic_handler::{{closure}}::hfefc5ab6450420bd
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/panicking.rs:579:13
  13:     0x7fade281a0d4 - std::sys_common::backtrace::__rust_end_short_backtrace::h3e4f67c6fca92ca4
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/sys_common/backtrace.rs:139:18
  14:     0x7fade281e239 - rust_begin_unwind
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/panicking.rs:577:5
  15:     0x7fade27e57f3 - core::panicking::panic_fmt::h9519158c6a4a8e92
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/core/src/panicking.rs:135:14
  16:     0x7fade27e56cd - core::panicking::panic::he4b7fa492097ef53
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/core/src/panicking.rs:48:5
  17:     0x7fade4c66284 - <rustc_middle[f81dc3bd746ca440]::ty::Term as rustc_infer[315d8358460fe4ad]::infer::at::ToTrace>::to_trace
  18:     0x7fade4ba7d00 - <rustc_infer[315d8358460fe4ad]::infer::InferCtxt>::commit_if_ok::<core[9c864a1268b8bc28]::result::Result<core[9c864a1268b8bc28]::option::Option<alloc[5657b11be84882bf]::vec::Vec<rustc_infer[315d8358460fe4ad]::traits::Obligation<rustc_middle[f81dc3bd746ca440]::ty::Predicate>>>, rustc_trait_selection[539f2e6de6887342]::traits::project::InProgress>, rustc_infer[315d8358460fe4ad]::traits::project::MismatchedProjectionTypes, rustc_trait_selection[539f2e6de6887342]::traits::project::poly_project_and_unify_type::{closure#0}>
  19:     0x7fade4ba99fc - <rustc_infer[315d8358460fe4ad]::infer::InferCtxt>::probe::<core[9c864a1268b8bc28]::result::Result<rustc_middle[f81dc3bd746ca440]::traits::select::EvaluationResult, rustc_middle[f81dc3bd746ca440]::traits::select::OverflowError>, <rustc_trait_selection[539f2e6de6887342]::traits::select::SelectionContext>::evaluation_probe<<rustc_trait_selection[539f2e6de6887342]::traits::select::SelectionContext>::evaluate_root_obligation::{closure#0}>::{closure#0}>
  20:     0x7fade4bb1d2c - <rustc_trait_selection[539f2e6de6887342]::traits::select::SelectionContext>::evaluate_root_obligation
  21:     0x7fade487ea1f - rustc_traits[aa9b450ff685432b]::evaluate_obligation::evaluate_obligation
  22:     0x7fade48e2624 - rustc_query_system[76c120c7b626130f]::query::plumbing::get_query::<rustc_query_impl[2379cdb3b7fbe0e9]::queries::evaluate_obligation, rustc_query_impl[2379cdb3b7fbe0e9]::plumbing::QueryCtxt>
  23:     0x7fade4919614 - <rustc_query_impl[2379cdb3b7fbe0e9]::Queries as rustc_middle[f81dc3bd746ca440]::ty::query::QueryEngine>::evaluate_obligation
  24:     0x7fade4b99990 - <rustc_infer[315d8358460fe4ad]::infer::InferCtxt as rustc_trait_selection[539f2e6de6887342]::traits::query::evaluate_obligation::InferCtxtExt>::predicate_must_hold_considering_regions
  25:     0x7fade4bfbed0 - <rustc_trait_selection[539f2e6de6887342]::traits::fulfill::FulfillProcessor>::progress_changed_obligations
  26:     0x7fade4c05f14 - <rustc_data_structures[9e5bb2a265815808]::obligation_forest::ObligationForest<rustc_trait_selection[539f2e6de6887342]::traits::fulfill::PendingPredicateObligation>>::process_obligations::<rustc_trait_selection[539f2e6de6887342]::traits::fulfill::FulfillProcessor, rustc_data_structures[9e5bb2a265815808]::obligation_forest::Outcome<rustc_trait_selection[539f2e6de6887342]::traits::fulfill::PendingPredicateObligation, rustc_infer[315d8358460fe4ad]::traits::FulfillmentErrorCode>>
  27:     0x7fade4bf9067 - <rustc_trait_selection[539f2e6de6887342]::traits::fulfill::FulfillmentContext as rustc_infer[315d8358460fe4ad]::traits::engine::TraitEngine>::select_where_possible
  28:     0x7fade4388ed9 - <rustc_typeck[37e53a7353aab7cc]::check::fn_ctxt::FnCtxt>::check_argument_types
  29:     0x7fade43761c9 - <rustc_typeck[37e53a7353aab7cc]::check::fn_ctxt::FnCtxt>::confirm_builtin_call
  30:     0x7fade4372d8a - <rustc_typeck[37e53a7353aab7cc]::check::fn_ctxt::FnCtxt>::check_call
  31:     0x7fade43b731f - <rustc_typeck[37e53a7353aab7cc]::check::fn_ctxt::FnCtxt>::check_expr_kind
  32:     0x7fade437deb6 - <rustc_typeck[37e53a7353aab7cc]::check::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
  33:     0x7fade43a54d2 - <rustc_typeck[37e53a7353aab7cc]::check::fn_ctxt::FnCtxt>::check_stmt
  34:     0x7fade43a6414 - <rustc_typeck[37e53a7353aab7cc]::check::fn_ctxt::FnCtxt>::check_block_with_expected
  35:     0x7fade437deb6 - <rustc_typeck[37e53a7353aab7cc]::check::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
  36:     0x7fade44bc96f - rustc_typeck[37e53a7353aab7cc]::check::check::check_fn
  37:     0x7fade4434dbb - <rustc_infer[315d8358460fe4ad]::infer::InferCtxtBuilder>::enter::<&rustc_middle[f81dc3bd746ca440]::ty::context::TypeckResults, <rustc_typeck[37e53a7353aab7cc]::check::inherited::InheritedBuilder>::enter<rustc_typeck[37e53a7353aab7cc]::check::typeck_with_fallback<rustc_typeck[37e53a7353aab7cc]::check::typeck::{closure#0}>::{closure#1}, &rustc_middle[f81dc3bd746ca440]::ty::context::TypeckResults>::{closure#0}>
  38:     0x7fade4412662 - rustc_typeck[37e53a7353aab7cc]::check::typeck
  39:     0x7fade48b0157 - rustc_query_system[76c120c7b626130f]::query::plumbing::try_execute_query::<rustc_query_impl[2379cdb3b7fbe0e9]::plumbing::QueryCtxt, rustc_query_system[76c120c7b626130f]::query::caches::DefaultCache<rustc_span[d0f60ce72bde622e]::def_id::LocalDefId, &rustc_middle[f81dc3bd746ca440]::ty::context::TypeckResults>>
  40:     0x7fade4911fec - <rustc_query_impl[2379cdb3b7fbe0e9]::Queries as rustc_middle[f81dc3bd746ca440]::ty::query::QueryEngine>::typeck
  41:     0x7fade301a19e - <rustc_save_analysis[e3c0767218553f8d]::dump_visitor::DumpVisitor as rustc_hir[ffba0bf86b6d8ca8]::intravisit::Visitor>::visit_item
  42:     0x7fade301e2e6 - <rustc_save_analysis[e3c0767218553f8d]::dump_visitor::DumpVisitor as rustc_hir[ffba0bf86b6d8ca8]::intravisit::Visitor>::visit_nested_item
  43:     0x7fade2ffffd7 - rustc_hir[ffba0bf86b6d8ca8]::intravisit::walk_mod::<rustc_save_analysis[e3c0767218553f8d]::dump_visitor::DumpVisitor>
  44:     0x7fade300b2b3 - <rustc_middle[f81dc3bd746ca440]::hir::map::Map>::walk_toplevel_module::<rustc_save_analysis[e3c0767218553f8d]::dump_visitor::DumpVisitor>
  45:     0x7fade3016d03 - <rustc_save_analysis[e3c0767218553f8d]::dump_visitor::DumpVisitor>::process_crate
  46:     0x7fade2fdd31e - <rustc_middle[f81dc3bd746ca440]::dep_graph::dep_node::DepKind as rustc_query_system[76c120c7b626130f]::dep_graph::DepKind>::with_deps::<rustc_save_analysis[e3c0767218553f8d]::process_crate<rustc_save_analysis[e3c0767218553f8d]::DumpHandler>::{closure#0}::{closure#0}, ()>
  47:     0x7fade2ff5478 - <std[22fd8536f279bacf]::thread::local::LocalKey<core[9c864a1268b8bc28]::cell::Cell<bool>>>::with::<rustc_middle[f81dc3bd746ca440]::ty::print::pretty::with_no_trimmed_paths<rustc_save_analysis[e3c0767218553f8d]::process_crate<rustc_save_analysis[e3c0767218553f8d]::DumpHandler>::{closure#0}, ()>::{closure#0}, ()>
  48:     0x7fade2fd096d - rustc_save_analysis[e3c0767218553f8d]::process_crate::<rustc_save_analysis[e3c0767218553f8d]::DumpHandler>
  49:     0x7fade2fd3065 - <rustc_session[6f4d93b48e654429]::session::Session>::time::<(), rustc_driver[b8c5cee21782833e]::run_compiler::{closure#1}::{closure#2}::{closure#3}::{closure#0}>
  50:     0x7fade4e578fe - <rustc_interface[ec08951694d4ef8a]::passes::QueryContext>::enter::<rustc_driver[b8c5cee21782833e]::run_compiler::{closure#1}::{closure#2}::{closure#3}, core[9c864a1268b8bc28]::result::Result<(), rustc_errors[1adefd6505a5cf85]::ErrorReported>>
  51:     0x7fade4e559ca - <rustc_interface[ec08951694d4ef8a]::interface::Compiler>::enter::<rustc_driver[b8c5cee21782833e]::run_compiler::{closure#1}::{closure#2}, core[9c864a1268b8bc28]::result::Result<core[9c864a1268b8bc28]::option::Option<rustc_interface[ec08951694d4ef8a]::queries::Linker>, rustc_errors[1adefd6505a5cf85]::ErrorReported>>
  52:     0x7fade4e587e6 - rustc_span[d0f60ce72bde622e]::with_source_map::<core[9c864a1268b8bc28]::result::Result<(), rustc_errors[1adefd6505a5cf85]::ErrorReported>, rustc_interface[ec08951694d4ef8a]::interface::create_compiler_and_run<core[9c864a1268b8bc28]::result::Result<(), rustc_errors[1adefd6505a5cf85]::ErrorReported>, rustc_driver[b8c5cee21782833e]::run_compiler::{closure#1}>::{closure#1}>
  53:     0x7fade4e553ae - rustc_interface[ec08951694d4ef8a]::interface::create_compiler_and_run::<core[9c864a1268b8bc28]::result::Result<(), rustc_errors[1adefd6505a5cf85]::ErrorReported>, rustc_driver[b8c5cee21782833e]::run_compiler::{closure#1}>
  54:     0x7fade4e3a362 - std[22fd8536f279bacf]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[ec08951694d4ef8a]::util::setup_callbacks_and_run_in_thread_pool_with_globals<rustc_interface[ec08951694d4ef8a]::interface::run_compiler<core[9c864a1268b8bc28]::result::Result<(), rustc_errors[1adefd6505a5cf85]::ErrorReported>, rustc_driver[b8c5cee21782833e]::run_compiler::{closure#1}>::{closure#0}, core[9c864a1268b8bc28]::result::Result<(), rustc_errors[1adefd6505a5cf85]::ErrorReported>>::{closure#0}, core[9c864a1268b8bc28]::result::Result<(), rustc_errors[1adefd6505a5cf85]::ErrorReported>>
  55:     0x7fade4e38db9 - <<std[22fd8536f279bacf]::thread::Builder>::spawn_unchecked_<rustc_interface[ec08951694d4ef8a]::util::setup_callbacks_and_run_in_thread_pool_with_globals<rustc_interface[ec08951694d4ef8a]::interface::run_compiler<core[9c864a1268b8bc28]::result::Result<(), rustc_errors[1adefd6505a5cf85]::ErrorReported>, rustc_driver[b8c5cee21782833e]::run_compiler::{closure#1}>::{closure#0}, core[9c864a1268b8bc28]::result::Result<(), rustc_errors[1adefd6505a5cf85]::ErrorReported>>::{closure#0}, core[9c864a1268b8bc28]::result::Result<(), rustc_errors[1adefd6505a5cf85]::ErrorReported>>::{closure#1} as core[9c864a1268b8bc28]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  56:     0x7fade282a5c3 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hd7d5c17359d3a784
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/alloc/src/boxed.rs:1854:9
  57:     0x7fade282a5c3 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::he103afaaa5161d8a
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/alloc/src/boxed.rs:1854:9
  58:     0x7fade282a5c3 - std::sys::unix::thread::Thread::new::thread_start::h84b2058a5227adde
                               at /rustc/1ea4851715893ee3f365a8ef09d47165e9a7864f/library/std/src/sys/unix/thread.rs:108:17
  59:     0x7fade2730259 - start_thread
  60:     0x7fade264c5e3 - __GI___clone
  61:                0x0 - <unknown>

error: internal compiler error: unexpected panic

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

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

note: rustc 1.60.0-nightly (1ea485171 2022-02-01) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z save-analysis

query stack during panic:
#0 [evaluate_obligation] evaluating trait selection obligation `<Bar as Foo>::N == usize`
#1 [typeck] type-checking `main`
end of query stack
error: aborting due to previous error

[matthiaskrgr]

searched nightlies: from nightly-2021-08-01 to nightly-2022-02-05
regressed nightly: nightly-2022-01-19
searched commit range: ee5d8d3...9ad5d82
regressed commit: 7bc7be8

bisected with cargo-bisect-rustc v0.6.1

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

cargo bisect-rustc --test-dir=/home/matthias/vcs/github/rust_bisect/foo --start=2021-08-01 --end=2022-02-05

cc @JulianKnodt

[JulianKnodt]

Ah yes, I need to implement a ToTrace::Term which was deferred from a previous PR because it caused significant changes in generated output