ice: no entry found for key non_lifetime_binders with late-bound const parameter in constant

[matthiaskrgr]

auto-reduced (treereduce-rust):

#![feature(non_lifetime_binders)]

fn walk2<'a, T: 'a>(_: T)
where
    for<const C: usize> [(); C]: 'a,
{
}

original:

#![feature(non_lifetime_binders)]

fn walk2<'a, T: 'a>(_: T)
where
    for<const C: usize> [(); C]: 'a, // replacing C by 1 fixes ice
{}

fn main() {}

Version information

rustc 1.78.0-nightly (f4cfd8720 2024-02-09)
binary: rustc
commit-hash: f4cfd872028398da2b2d85c368c51f4d007dc6af
commit-date: 2024-02-09
host: x86_64-unknown-linux-gnu
release: 1.78.0-nightly
LLVM version: 17.0.6

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

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.V9RATaOuuJaC/rustc_testrunner_tmpdir_reporting.CtMPsSqyI46C/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.V9RATaOuuJaC/rustc_testrunner_tmpdir_reporting.CtMPsSqyI46C/mvce.rs:7:2
  |
7 | }
  |  ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.V9RATaOuuJaC/rustc_testrunner_tmpdir_reporting.CtMPsSqyI46C/mvce.rs`

error: cannot capture late-bound const parameter in constant
 --> /tmp/icemaker_global_tempdir.V9RATaOuuJaC/rustc_testrunner_tmpdir_reporting.CtMPsSqyI46C/mvce.rs:5:30
  |
5 |     for<const C: usize> [(); C]: 'a,
  |         --------------       ^
  |         |
  |         parameter defined here

thread 'rustc' panicked at compiler/rustc_mir_build/src/thir/cx/expr.rs:887:59:
no entry found for key
stack backtrace:
   0:     0x7f90f23e1946 - std::backtrace_rs::backtrace::libunwind::trace::hb28756ba02a3d69b
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5
   1:     0x7f90f23e1946 - std::backtrace_rs::backtrace::trace_unsynchronized::h4059a8c1298faac5
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f90f23e1946 - std::sys_common::backtrace::_print_fmt::hd497b104503e03df
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/sys_common/backtrace.rs:68:5
   3:     0x7f90f23e1946 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hc452c05edd0934f1
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7f90f2434390 - core::fmt::rt::Argument::fmt::h9d45194fabe22b74
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/core/src/fmt/rt.rs:142:9
   5:     0x7f90f2434390 - core::fmt::write::h2b690ea9afc76b6a
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/core/src/fmt/mod.rs:1120:17
   6:     0x7f90f23d50ff - std::io::Write::write_fmt::h1113da361aa3c239
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/io/mod.rs:1854:15
   7:     0x7f90f23e1724 - std::sys_common::backtrace::_print::h8571c116cfdaf0e3
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7f90f23e1724 - std::sys_common::backtrace::print::h15612d1cb18f5748
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7f90f23e44e7 - std::panicking::default_hook::{{closure}}::h6ec650d8e0f53942
  10:     0x7f90f23e4249 - std::panicking::default_hook::h6789db044ec621ae
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/panicking.rs:292:9
  11:     0x7f90ef125e6c - std[2db7d671f3a9f29e]::panicking::update_hook::<alloc[8a21bb79ecee740c]::boxed::Box<rustc_driver_impl[dad15490f0d3dd55]::install_ice_hook::{closure#0}>>::{closure#0}
  12:     0x7f90f23e4c36 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h50a1085617a0c032
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/alloc/src/boxed.rs:2029:9
  13:     0x7f90f23e4c36 - std::panicking::rust_panic_with_hook::hc9844a49c9f95922
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/panicking.rs:785:13
  14:     0x7f90f23e4982 - std::panicking::begin_panic_handler::{{closure}}::h8dedac3fc8ea08c9
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/panicking.rs:659:13
  15:     0x7f90f23e1e46 - std::sys_common::backtrace::__rust_end_short_backtrace::h4a51b280e6e2cc4e
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/sys_common/backtrace.rs:171:18
  16:     0x7f90f23e46d4 - rust_begin_unwind
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/panicking.rs:647:5
  17:     0x7f90f2430a95 - core::panicking::panic_fmt::hcd0ca5c421be097d
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/core/src/panicking.rs:72:14
  18:     0x7f90f2430843 - core::panicking::panic_display::h3cdbc3fe443e829c
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/core/src/panicking.rs:196:5
  19:     0x7f90f2430843 - core::panicking::panic_str::h85c6aabed1330d1c
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/core/src/panicking.rs:171:5
  20:     0x7f90f2430843 - core::option::expect_failed::h1778fccd1b5de473
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/core/src/option.rs:1987:5
  21:     0x7f90f08b449c - <rustc_mir_build[55ee9063a4de6d06]::thir::cx::Cx>::mirror_expr
  22:     0x7f90f07d9509 - rustc_mir_build[55ee9063a4de6d06]::thir::cx::thir_body
  23:     0x7f90f07d8ed4 - rustc_query_impl[38298c29941606b]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[38298c29941606b]::query_impl::thir_body::dynamic_query::{closure#2}::{closure#0}, rustc_middle[4117828168ce66f2]::query::erase::Erased<[u8; 16usize]>>
  24:     0x7f90f0a35786 - rustc_query_system[596b756f2478c92c]::query::plumbing::try_execute_query::<rustc_query_impl[38298c29941606b]::DynamicConfig<rustc_query_system[596b756f2478c92c]::query::caches::VecCache<rustc_span[13fbbf930593c3af]::def_id::LocalDefId, rustc_middle[4117828168ce66f2]::query::erase::Erased<[u8; 16usize]>>, false, false, false>, rustc_query_impl[38298c29941606b]::plumbing::QueryCtxt, false>
  25:     0x7f90f0a353d5 - rustc_query_impl[38298c29941606b]::query_impl::thir_body::get_query_non_incr::__rust_end_short_backtrace
  26:     0x7f90f082de65 - rustc_mir_build[55ee9063a4de6d06]::check_unsafety::check_unsafety
  27:     0x7f90f082dd49 - rustc_query_impl[38298c29941606b]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[38298c29941606b]::query_impl::check_unsafety::dynamic_query::{closure#2}::{closure#0}, rustc_middle[4117828168ce66f2]::query::erase::Erased<[u8; 0usize]>>
  28:     0x7f90f0c8b64e - rustc_query_system[596b756f2478c92c]::query::plumbing::try_execute_query::<rustc_query_impl[38298c29941606b]::DynamicConfig<rustc_query_system[596b756f2478c92c]::query::caches::VecCache<rustc_span[13fbbf930593c3af]::def_id::LocalDefId, rustc_middle[4117828168ce66f2]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[38298c29941606b]::plumbing::QueryCtxt, false>
  29:     0x7f90f0c8b317 - rustc_query_impl[38298c29941606b]::query_impl::check_unsafety::get_query_non_incr::__rust_end_short_backtrace
  30:     0x7f90f0e7fcc6 - rustc_interface[efaa592dac13667a]::passes::analysis
  31:     0x7f90f0e7f71f - rustc_query_impl[38298c29941606b]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[38298c29941606b]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[4117828168ce66f2]::query::erase::Erased<[u8; 1usize]>>
  32:     0x7f90f1127d72 - rustc_query_system[596b756f2478c92c]::query::plumbing::try_execute_query::<rustc_query_impl[38298c29941606b]::DynamicConfig<rustc_query_system[596b756f2478c92c]::query::caches::SingleCache<rustc_middle[4117828168ce66f2]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[38298c29941606b]::plumbing::QueryCtxt, false>
  33:     0x7f90f1127ad5 - rustc_query_impl[38298c29941606b]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  34:     0x7f90f1136b42 - rustc_interface[efaa592dac13667a]::interface::run_compiler::<core[cacc4eb881020547]::result::Result<(), rustc_span[13fbbf930593c3af]::ErrorGuaranteed>, rustc_driver_impl[dad15490f0d3dd55]::run_compiler::{closure#0}>::{closure#0}
  35:     0x7f90f139ee08 - std[2db7d671f3a9f29e]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[efaa592dac13667a]::util::run_in_thread_with_globals<rustc_interface[efaa592dac13667a]::util::run_in_thread_pool_with_globals<rustc_interface[efaa592dac13667a]::interface::run_compiler<core[cacc4eb881020547]::result::Result<(), rustc_span[13fbbf930593c3af]::ErrorGuaranteed>, rustc_driver_impl[dad15490f0d3dd55]::run_compiler::{closure#0}>::{closure#0}, core[cacc4eb881020547]::result::Result<(), rustc_span[13fbbf930593c3af]::ErrorGuaranteed>>::{closure#0}, core[cacc4eb881020547]::result::Result<(), rustc_span[13fbbf930593c3af]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[cacc4eb881020547]::result::Result<(), rustc_span[13fbbf930593c3af]::ErrorGuaranteed>>
  36:     0x7f90f139ec37 - <<std[2db7d671f3a9f29e]::thread::Builder>::spawn_unchecked_<rustc_interface[efaa592dac13667a]::util::run_in_thread_with_globals<rustc_interface[efaa592dac13667a]::util::run_in_thread_pool_with_globals<rustc_interface[efaa592dac13667a]::interface::run_compiler<core[cacc4eb881020547]::result::Result<(), rustc_span[13fbbf930593c3af]::ErrorGuaranteed>, rustc_driver_impl[dad15490f0d3dd55]::run_compiler::{closure#0}>::{closure#0}, core[cacc4eb881020547]::result::Result<(), rustc_span[13fbbf930593c3af]::ErrorGuaranteed>>::{closure#0}, core[cacc4eb881020547]::result::Result<(), rustc_span[13fbbf930593c3af]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[cacc4eb881020547]::result::Result<(), rustc_span[13fbbf930593c3af]::ErrorGuaranteed>>::{closure#1} as core[cacc4eb881020547]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  37:     0x7f90f23ee2d5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h507eeaa619802b96
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/alloc/src/boxed.rs:2015:9
  38:     0x7f90f23ee2d5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h6587eb2d6c93a7aa
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/alloc/src/boxed.rs:2015:9
  39:     0x7f90f23ee2d5 - std::sys::pal::unix::thread::Thread::new::thread_start::h52c520a06bfbe43e
                               at /rustc/f4cfd872028398da2b2d85c368c51f4d007dc6af/library/std/src/sys/pal/unix/thread.rs:108:17
  40:     0x7f90ec2aa9eb - <unknown>
  41:     0x7f90ec32e7cc - <unknown>
  42:                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 1.78.0-nightly (f4cfd8720 2024-02-09) running on x86_64-unknown-linux-gnu

query stack during panic:
#0 [thir_body] building THIR for `walk2::{constant#0}`
#1 [check_unsafety] unsafety-checking `walk2::{constant#0}`
#2 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 2 previous errors; 1 warning emitted

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

[matthiaskrgr]

Another one of #120550 it seems cc @oli-obk

[oli-obk]

Huh didn't I just fix that?

[matthiaskrgr]

Might be another "layer" of crashes below #120779 and #120816 ?

edit: or is there a pending pr?

[oli-obk]

Yea it's #120847