ICE: closures: `no entry found for key`

[matthiaskrgr]

auto-reduced (treereduce-rust):

trait Foo {
    fn test() -> impl Fn(u32) -> u32 {
        || x.count_ones()
    }
}

original:

// compile-flags: -Ztrait-solver=next
// check-pass

trait Foo {
    fn test() -> impl Fn(u32) -> u32 {
        || x.count_ones()
    }
}

fn test() -> impl Fn(u32) -> u32 {
        |x| x.count_ones()
    }

Version information

rustc 1.76.0-nightly (1ab2bcda4 2023-11-13)
binary: rustc
commit-hash: 1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2
commit-date: 2023-11-13
host: x86_64-unknown-linux-gnu
release: 1.76.0-nightly
LLVM version: 17.0.4

Command:
/home/matthias/.rustup/toolchains/master/bin/rustc

Program output

error[E0425]: cannot find value `x` in this scope
 --> /tmp/icemaker_global_tempdir.fsYCHepUila8/rustc_testrunner_tmpdir_reporting.iEesmi5L3ZBB/mvce.rs:3:12
  |
3 |         || x.count_ones()
  |            ^ not found in this scope

error[E0601]: `main` function not found in crate `mvce`
 --> /tmp/icemaker_global_tempdir.fsYCHepUila8/rustc_testrunner_tmpdir_reporting.iEesmi5L3ZBB/mvce.rs:5:2
  |
5 | }
  |  ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.fsYCHepUila8/rustc_testrunner_tmpdir_reporting.iEesmi5L3ZBB/mvce.rs`

error[E0593]: closure is expected to take 1 argument, but it takes 0 arguments
 --> /tmp/icemaker_global_tempdir.fsYCHepUila8/rustc_testrunner_tmpdir_reporting.iEesmi5L3ZBB/mvce.rs:2:18
  |
2 |     fn test() -> impl Fn(u32) -> u32 {
  |                  ^^^^^^^^^^^^^^^^^^^ expected closure that takes 1 argument
3 |         || x.count_ones()
  |         -- takes 0 arguments
  |
help: consider changing the closure to take and ignore the expected argument
  |
3 |         |_| x.count_ones()
  |         ~~~

thread 'rustc' panicked at compiler/rustc_middle/src/ty/closure.rs:262:62:
no entry found for key
stack backtrace:
   0:     0x7f6cbebc461c - std::backtrace_rs::backtrace::libunwind::trace::h02700d0b9106f6ee
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5
   1:     0x7f6cbebc461c - std::backtrace_rs::backtrace::trace_unsynchronized::h47697d498917cc3a
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f6cbebc461c - std::sys_common::backtrace::_print_fmt::h61e153e4a9281095
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/sys_common/backtrace.rs:67:5
   3:     0x7f6cbebc461c - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h19e4154d0ad4df85
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7f6cbec17620 - core::fmt::rt::Argument::fmt::hff5f47072cf5d938
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/core/src/fmt/rt.rs:142:9
   5:     0x7f6cbec17620 - core::fmt::write::he88bb017eb7320eb
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/core/src/fmt/mod.rs:1120:17
   6:     0x7f6cbebb84af - std::io::Write::write_fmt::he5d70b9e85592aa1
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/io/mod.rs:1762:15
   7:     0x7f6cbebc4404 - std::sys_common::backtrace::_print::h0f9eda7450aa4845
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7f6cbebc4404 - std::sys_common::backtrace::print::h2824fde3c1bc9cf4
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7f6cbebc7097 - std::panicking::default_hook::{{closure}}::h1805dbb298de9c25
  10:     0x7f6cbebc6dff - std::panicking::default_hook::ha21d0b6721dee8b1
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/panicking.rs:292:9
  11:     0x7f6cbb8ef240 - std[ebdb09ff591878d7]::panicking::update_hook::<alloc[22a98c5663efe855]::boxed::Box<rustc_driver_impl[5634551524408def]::install_ice_hook::{closure#0}>>::{closure#0}
  12:     0x7f6cbebc77d8 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::ha9c965637066c11f
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/alloc/src/boxed.rs:2021:9
  13:     0x7f6cbebc77d8 - std::panicking::rust_panic_with_hook::hc95115aac9b43978
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/panicking.rs:783:13
  14:     0x7f6cbebc752e - std::panicking::begin_panic_handler::{{closure}}::hadf007604e83e37e
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/panicking.rs:657:13
  15:     0x7f6cbebc4ae6 - std::sys_common::backtrace::__rust_end_short_backtrace::h4243b36539a052a4
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/sys_common/backtrace.rs:170:18
  16:     0x7f6cbebc7292 - rust_begin_unwind
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/panicking.rs:645:5
  17:     0x7f6cbec13d05 - core::panicking::panic_fmt::h0396d052df2d310c
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/core/src/panicking.rs:72:14
  18:     0x7f6cbec13ab3 - core::panicking::panic_display::h5c3aa0fffe5c1bb1
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/core/src/panicking.rs:178:5
  19:     0x7f6cbec13ab3 - core::panicking::panic_str::h9aa8a76502539bda
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/core/src/panicking.rs:152:5
  20:     0x7f6cbec13ab3 - core::option::expect_failed::h3b7f6a03d7af5d21
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/core/src/option.rs:1985:5
  21:     0x7f6cbe135afe - rustc_middle[29cace5c4948c514]::ty::closure::closure_typeinfo.cold.0
  22:     0x7f6cbd5ec118 - rustc_query_impl[94d6f6b2e1186b94]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[94d6f6b2e1186b94]::query_impl::closure_typeinfo::dynamic_query::{closure#2}::{closure#0}, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 64usize]>>
  23:     0x7f6cbd5ec0f3 - <rustc_query_impl[94d6f6b2e1186b94]::query_impl::closure_typeinfo::dynamic_query::{closure#2} as core[578f67fda67372d9]::ops::function::FnOnce<(rustc_middle[29cace5c4948c514]::ty::context::TyCtxt, rustc_span[dd40b738055021c1]::def_id::LocalDefId)>>::call_once
  24:     0x7f6cbd5eb6aa - rustc_query_system[303543fe729c1791]::query::plumbing::try_execute_query::<rustc_query_impl[94d6f6b2e1186b94]::DynamicConfig<rustc_query_system[303543fe729c1791]::query::caches::VecCache<rustc_span[dd40b738055021c1]::def_id::LocalDefId, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 64usize]>>, false, false, false>, rustc_query_impl[94d6f6b2e1186b94]::plumbing::QueryCtxt, false>
  25:     0x7f6cbd5eb3f1 - rustc_query_impl[94d6f6b2e1186b94]::query_impl::closure_typeinfo::get_query_non_incr::__rust_end_short_backtrace
  26:     0x7f6cbd5eabbe - <rustc_middle[29cace5c4948c514]::ty::context::TyCtxt>::closure_captures
  27:     0x7f6cbda01438 - rustc_borrowck[45e3ca37d614772c]::do_mir_borrowck
  28:     0x7f6cbda002ca - rustc_borrowck[45e3ca37d614772c]::mir_borrowck
  29:     0x7f6cbd9ffd6f - rustc_query_impl[94d6f6b2e1186b94]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[94d6f6b2e1186b94]::query_impl::mir_borrowck::dynamic_query::{closure#2}::{closure#0}, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 8usize]>>
  30:     0x7f6cbcceb483 - rustc_query_system[303543fe729c1791]::query::plumbing::try_execute_query::<rustc_query_impl[94d6f6b2e1186b94]::DynamicConfig<rustc_query_system[303543fe729c1791]::query::caches::VecCache<rustc_span[dd40b738055021c1]::def_id::LocalDefId, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[94d6f6b2e1186b94]::plumbing::QueryCtxt, false>
  31:     0x7f6cbcceb050 - rustc_query_impl[94d6f6b2e1186b94]::query_impl::mir_borrowck::get_query_non_incr::__rust_end_short_backtrace
  32:     0x7f6cbdc154f1 - <rustc_hir_analysis[9e914fc505a4e762]::collect::type_of::opaque::RpitConstraintChecker>::check
  33:     0x7f6cbb1780d5 - <rustc_hir_analysis[9e914fc505a4e762]::collect::type_of::opaque::RpitConstraintChecker as rustc_hir[5a61b80be043b6a0]::intravisit::Visitor>::visit_expr
  34:     0x7f6cbd96c770 - rustc_hir_analysis[9e914fc505a4e762]::collect::type_of::type_of_opaque
  35:     0x7f6cbd96be9b - rustc_query_impl[94d6f6b2e1186b94]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[94d6f6b2e1186b94]::query_impl::type_of_opaque::dynamic_query::{closure#2}::{closure#0}, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 8usize]>>
  36:     0x7f6cbcc53354 - rustc_query_system[303543fe729c1791]::query::plumbing::try_execute_query::<rustc_query_impl[94d6f6b2e1186b94]::DynamicConfig<rustc_query_system[303543fe729c1791]::query::caches::DefaultCache<rustc_span[dd40b738055021c1]::def_id::DefId, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[94d6f6b2e1186b94]::plumbing::QueryCtxt, false>
  37:     0x7f6cbdc587de - rustc_query_impl[94d6f6b2e1186b94]::query_impl::type_of_opaque::get_query_non_incr::__rust_end_short_backtrace
  38:     0x7f6cbccc0a38 - rustc_middle[29cace5c4948c514]::query::plumbing::query_get_at::<rustc_query_system[303543fe729c1791]::query::caches::DefaultCache<rustc_span[dd40b738055021c1]::def_id::DefId, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 8usize]>>>
  39:     0x7f6cbadd293f - rustc_hir_analysis[9e914fc505a4e762]::collect::type_of::type_of
  40:     0x7f6cbcc544b6 - rustc_query_impl[94d6f6b2e1186b94]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[94d6f6b2e1186b94]::query_impl::type_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 8usize]>>
  41:     0x7f6cbcc53354 - rustc_query_system[303543fe729c1791]::query::plumbing::try_execute_query::<rustc_query_impl[94d6f6b2e1186b94]::DynamicConfig<rustc_query_system[303543fe729c1791]::query::caches::DefaultCache<rustc_span[dd40b738055021c1]::def_id::DefId, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[94d6f6b2e1186b94]::plumbing::QueryCtxt, false>
  42:     0x7f6cbcc52f1b - rustc_query_impl[94d6f6b2e1186b94]::query_impl::type_of::get_query_non_incr::__rust_end_short_backtrace
  43:     0x7f6cbccc0a38 - rustc_middle[29cace5c4948c514]::query::plumbing::query_get_at::<rustc_query_system[303543fe729c1791]::query::caches::DefaultCache<rustc_span[dd40b738055021c1]::def_id::DefId, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 8usize]>>>
  44:     0x7f6cbd33164c - rustc_hir_analysis[9e914fc505a4e762]::check::check::check_mod_item_types
  45:     0x7f6cbd330053 - rustc_query_impl[94d6f6b2e1186b94]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[94d6f6b2e1186b94]::query_impl::check_mod_item_types::dynamic_query::{closure#2}::{closure#0}, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 0usize]>>
  46:     0x7f6cbd5d4bbb - rustc_query_system[303543fe729c1791]::query::plumbing::try_execute_query::<rustc_query_impl[94d6f6b2e1186b94]::DynamicConfig<rustc_query_system[303543fe729c1791]::query::caches::DefaultCache<rustc_span[dd40b738055021c1]::def_id::LocalModDefId, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[94d6f6b2e1186b94]::plumbing::QueryCtxt, false>
  47:     0x7f6cbd5d4597 - rustc_query_impl[94d6f6b2e1186b94]::query_impl::check_mod_item_types::get_query_non_incr::__rust_end_short_backtrace
  48:     0x7f6cbd1b00d5 - rustc_hir_analysis[9e914fc505a4e762]::check_crate
  49:     0x7f6cbcf79957 - rustc_interface[91b7e6a880170ab5]::passes::analysis
  50:     0x7f6cbcf795b7 - rustc_query_impl[94d6f6b2e1186b94]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[94d6f6b2e1186b94]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 1usize]>>
  51:     0x7f6cbdb96be4 - rustc_query_system[303543fe729c1791]::query::plumbing::try_execute_query::<rustc_query_impl[94d6f6b2e1186b94]::DynamicConfig<rustc_query_system[303543fe729c1791]::query::caches::SingleCache<rustc_middle[29cace5c4948c514]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[94d6f6b2e1186b94]::plumbing::QueryCtxt, false>
  52:     0x7f6cbdb969d5 - rustc_query_impl[94d6f6b2e1186b94]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  53:     0x7f6cbdb9f5ff - rustc_interface[91b7e6a880170ab5]::interface::run_compiler::<core[578f67fda67372d9]::result::Result<(), rustc_span[dd40b738055021c1]::ErrorGuaranteed>, rustc_driver_impl[5634551524408def]::run_compiler::{closure#1}>::{closure#0}
  54:     0x7f6cbdba691a - std[ebdb09ff591878d7]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[91b7e6a880170ab5]::util::run_in_thread_with_globals<rustc_interface[91b7e6a880170ab5]::util::run_in_thread_pool_with_globals<rustc_interface[91b7e6a880170ab5]::interface::run_compiler<core[578f67fda67372d9]::result::Result<(), rustc_span[dd40b738055021c1]::ErrorGuaranteed>, rustc_driver_impl[5634551524408def]::run_compiler::{closure#1}>::{closure#0}, core[578f67fda67372d9]::result::Result<(), rustc_span[dd40b738055021c1]::ErrorGuaranteed>>::{closure#0}, core[578f67fda67372d9]::result::Result<(), rustc_span[dd40b738055021c1]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[578f67fda67372d9]::result::Result<(), rustc_span[dd40b738055021c1]::ErrorGuaranteed>>
  55:     0x7f6cbdba6743 - <<std[ebdb09ff591878d7]::thread::Builder>::spawn_unchecked_<rustc_interface[91b7e6a880170ab5]::util::run_in_thread_with_globals<rustc_interface[91b7e6a880170ab5]::util::run_in_thread_pool_with_globals<rustc_interface[91b7e6a880170ab5]::interface::run_compiler<core[578f67fda67372d9]::result::Result<(), rustc_span[dd40b738055021c1]::ErrorGuaranteed>, rustc_driver_impl[5634551524408def]::run_compiler::{closure#1}>::{closure#0}, core[578f67fda67372d9]::result::Result<(), rustc_span[dd40b738055021c1]::ErrorGuaranteed>>::{closure#0}, core[578f67fda67372d9]::result::Result<(), rustc_span[dd40b738055021c1]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[578f67fda67372d9]::result::Result<(), rustc_span[dd40b738055021c1]::ErrorGuaranteed>>::{closure#1} as core[578f67fda67372d9]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  56:     0x7f6cbebd1695 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h37189f8e9fbe515c
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/alloc/src/boxed.rs:2007:9
  57:     0x7f6cbebd1695 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hef966e35865ebb05
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/alloc/src/boxed.rs:2007:9
  58:     0x7f6cbebd1695 - std::sys::unix::thread::Thread::new::thread_start::h7d0959f9b7c2f0a7
                               at /rustc/1ab2bcda4303b81b1124b88ddff6f5e9a68d7bc2/library/std/src/sys/unix/thread.rs:108:17
  59:     0x7f6cb8aaa9eb - <unknown>
  60:     0x7f6cb8b2e7cc - <unknown>
  61:                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: rustc 1.76.0-nightly (1ab2bcda4 2023-11-13) running on x86_64-unknown-linux-gnu

query stack during panic:
#0 [closure_typeinfo] finding symbols for captures of closure `Foo::test::{closure#0}`
#1 [mir_borrowck] borrow-checking `Foo::test::{closure#0}`
#2 [type_of_opaque] computing type of opaque `Foo::test::{opaque#0}`
#3 [type_of] computing type of `Foo::test::{opaque#0}`
#4 [check_mod_item_types] checking item types in top-level module
#5 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 3 previous errors

Some errors have detailed explanations: E0425, E0593, E0601.
For more information about an error, try `rustc --explain E0425`.

[matthiaskrgr]

Regression in nightly-2023-11-08
504f63e / #117418 ping @compiler-errors

[compiler-errors]

I think @bvanjoi is fixing an issue that may have the same root cause.