ICE: Unsafe binder types: Unimplemented

[matthiaskrgr]

Code

crashes on stable as well

struct A {
  b: unsafe<>()
}
impl A {
  fn c() {
    A {}
  }
}

Meta

rustc --version --verbose:

rustc 1.87.0-nightly (00f245915 2025-02-26)
binary: rustc
commit-hash: 00f245915b0c7839d42c26f9628220c4f1b93bf6
commit-date: 2025-02-26
host: x86_64-unknown-linux-gnu
release: 1.87.0-nightly
LLVM version: 20.1.0

Error output

error[E0658]: unsafe binder types are experimental
 --> a.rs:2:6
  |
2 |   b: unsafe<>()
  |      ^^^^^^^^^^
  |
  = note: see issue #130516 <https://github.com/rust-lang/rust/issues/130516> for more information
  = help: add `#![feature(unsafe_binders)]` to the crate attributes to enable
  = note: this compiler was built on 2025-02-26; consider upgrading it if it is out of date

error[E0601]: `main` function not found in crate `a`
 --> a.rs:8:2
  |
8 | }
  |  ^ consider adding a `main` function to `a.rs`

error[E0063]: missing field `b` in initializer of `A`
 --> a.rs:6:5
  |
6 |     A {}
  |     ^ missing `b`

Backtrace

thread 'rustc' panicked at compiler/rustc_ty_utils/src/ty.rs:40:28:
not yet implemented
stack backtrace:
   0:     0x772c745c4ac4 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::hf5f9bba251506256
   1:     0x772c74e166ec - core::fmt::write::h6b85c82de70b7598
   2:     0x772c75e96291 - std::io::Write::write_fmt::h2528afb58ed912d8
   3:     0x772c745c4922 - std::sys::backtrace::BacktraceLock::print::h260dc8c239dad99b
   4:     0x772c745c715e - std::panicking::default_hook::{{closure}}::h112b7744a5445b18
   5:     0x772c745c6d34 - std::panicking::default_hook::h8eba92c350f78920
   6:     0x772c73723bb7 - std[63ccf99907648090]::panicking::update_hook::<alloc[40f330a4b1dfe34e]::boxed::Box<rustc_driver_impl[44d86c3fd4736e11]::install_ice_hook::{closure#1}>>::{closure#0}
   7:     0x772c745c79d3 - std::panicking::rust_panic_with_hook::hc531b406179c95b0
   8:     0x772c745c7696 - std::panicking::begin_panic_handler::{{closure}}::hcdc071f581557557
   9:     0x772c745c4f89 - std::sys::backtrace::__rust_end_short_backtrace::h0fbed5a87d7f358d
  10:     0x772c745c738d - rust_begin_unwind
  11:     0x772c71259d50 - core::panicking::panic_fmt::h459d961e1d0721af
  12:     0x772c71c07cfc - core::panicking::panic::h5c546bff560aff35
  13:     0x772c767a5832 - rustc_ty_utils[9eb7a3d45272fa1]::ty::sized_constraint_for_ty.cold
  14:     0x772c756b4aac - rustc_ty_utils[9eb7a3d45272fa1]::ty::adt_sized_constraint
  15:     0x772c756b4a09 - rustc_query_impl[14741ea0e0b48805]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[14741ea0e0b48805]::query_impl::adt_sized_constraint::dynamic_query::{closure#2}::{closure#0}, rustc_middle[fe836999645634e1]::query::erase::Erased<[u8; 8usize]>>
  16:     0x772c74f3ed32 - rustc_query_system[964dfde9a4346c01]::query::plumbing::try_execute_query::<rustc_query_impl[14741ea0e0b48805]::DynamicConfig<rustc_query_system[964dfde9a4346c01]::query::caches::DefIdCache<rustc_middle[fe836999645634e1]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[14741ea0e0b48805]::plumbing::QueryCtxt, false>
  17:     0x772c757f12de - rustc_query_impl[14741ea0e0b48805]::query_impl::adt_sized_constraint::get_query_non_incr::__rust_end_short_backtrace
  18:     0x772c757f0a54 - rustc_middle[fe836999645634e1]::query::plumbing::query_get_at::<rustc_query_system[964dfde9a4346c01]::query::caches::DefIdCache<rustc_middle[fe836999645634e1]::query::erase::Erased<[u8; 8usize]>>>
  19:     0x772c75e6899a - <rustc_trait_selection[cd372552e19510e3]::traits::select::SelectionContext>::assemble_candidates
  20:     0x772c74f73a47 - <rustc_trait_selection[cd372552e19510e3]::traits::select::SelectionContext>::candidate_from_obligation::{closure#0}
  21:     0x772c74f6d039 - <rustc_trait_selection[cd372552e19510e3]::traits::select::SelectionContext>::evaluate_trait_predicate_recursively
  22:     0x772c74f6b959 - <rustc_trait_selection[cd372552e19510e3]::traits::select::SelectionContext>::evaluate_predicate_recursively
  23:     0x772c74f6de6f - <rustc_trait_selection[cd372552e19510e3]::traits::select::SelectionContext>::evaluate_trait_predicate_recursively
  24:     0x772c74f7f0ca - <rustc_trait_selection[cd372552e19510e3]::traits::select::SelectionContext>::evaluate_root_obligation
  25:     0x772c74f7d87e - rustc_traits[af874b8370063dd9]::evaluate_obligation::evaluate_obligation
  26:     0x772c74f7d369 - rustc_query_impl[14741ea0e0b48805]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[14741ea0e0b48805]::query_impl::evaluate_obligation::dynamic_query::{closure#2}::{closure#0}, rustc_middle[fe836999645634e1]::query::erase::Erased<[u8; 2usize]>>
  27:     0x772c74f7c7c8 - rustc_query_system[964dfde9a4346c01]::query::plumbing::try_execute_query::<rustc_query_impl[14741ea0e0b48805]::DynamicConfig<rustc_query_system[964dfde9a4346c01]::query::caches::DefaultCache<rustc_type_ir[82ba529ce6c8f4bf]::canonical::CanonicalQueryInput<rustc_middle[fe836999645634e1]::ty::context::TyCtxt, rustc_middle[fe836999645634e1]::ty::ParamEnvAnd<rustc_middle[fe836999645634e1]::ty::predicate::Predicate>>, rustc_middle[fe836999645634e1]::query::erase::Erased<[u8; 2usize]>>, false, false, false>, rustc_query_impl[14741ea0e0b48805]::plumbing::QueryCtxt, false>
  28:     0x772c74f7c3de - rustc_query_impl[14741ea0e0b48805]::query_impl::evaluate_obligation::get_query_non_incr::__rust_end_short_backtrace
  29:     0x772c7529b5d4 - <rustc_infer[a87ff89fafd98458]::infer::InferCtxt as rustc_trait_selection[cd372552e19510e3]::traits::query::evaluate_obligation::InferCtxtExt>::evaluate_obligation_no_overflow
  30:     0x772c73a467bc - <rustc_hir_typeck[97f398f206835c2f]::fn_ctxt::FnCtxt>::suggest_into
  31:     0x772c73a0439b - <rustc_hir_typeck[97f398f206835c2f]::fn_ctxt::FnCtxt>::emit_type_mismatch_suggestions
  32:     0x772c73a062e1 - <rustc_hir_typeck[97f398f206835c2f]::fn_ctxt::FnCtxt>::emit_coerce_suggestions
  33:     0x772c75cf1013 - <rustc_hir_typeck[97f398f206835c2f]::fn_ctxt::FnCtxt>::check_expr_block
  34:     0x772c75cf563c - <rustc_hir_typeck[97f398f206835c2f]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
  35:     0x772c751e9309 - rustc_hir_typeck[97f398f206835c2f]::check::check_fn
  36:     0x772c751dc46a - rustc_hir_typeck[97f398f206835c2f]::typeck_with_inspect::{closure#0}
  37:     0x772c751dba70 - rustc_query_impl[14741ea0e0b48805]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[14741ea0e0b48805]::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle[fe836999645634e1]::query::erase::Erased<[u8; 8usize]>>
  38:     0x772c7527d34c - rustc_query_system[964dfde9a4346c01]::query::plumbing::try_execute_query::<rustc_query_impl[14741ea0e0b48805]::DynamicConfig<rustc_data_structures[370e96b114838f77]::vec_cache::VecCache<rustc_span[d695c239c1f6fe20]::def_id::LocalDefId, rustc_middle[fe836999645634e1]::query::erase::Erased<[u8; 8usize]>, rustc_query_system[964dfde9a4346c01]::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl[14741ea0e0b48805]::plumbing::QueryCtxt, false>
  39:     0x772c7527c3dc - rustc_query_impl[14741ea0e0b48805]::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
  40:     0x772c7527c07f - <rustc_middle[fe836999645634e1]::ty::context::TyCtxt>::par_hir_body_owners::<rustc_hir_analysis[5392223966627bd9]::check_crate::{closure#3}>::{closure#0}
  41:     0x772c7527b6f9 - rustc_hir_analysis[5392223966627bd9]::check_crate
  42:     0x772c7527592a - rustc_interface[e696fb279c73d43f]::passes::run_required_analyses
  43:     0x772c75e9223a - rustc_interface[e696fb279c73d43f]::passes::analysis
  44:     0x772c75e92219 - rustc_query_impl[14741ea0e0b48805]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[14741ea0e0b48805]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[fe836999645634e1]::query::erase::Erased<[u8; 0usize]>>
  45:     0x772c75ee794b - rustc_query_system[964dfde9a4346c01]::query::plumbing::try_execute_query::<rustc_query_impl[14741ea0e0b48805]::DynamicConfig<rustc_query_system[964dfde9a4346c01]::query::caches::SingleCache<rustc_middle[fe836999645634e1]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[14741ea0e0b48805]::plumbing::QueryCtxt, false>
  46:     0x772c75ee7639 - rustc_query_impl[14741ea0e0b48805]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  47:     0x772c75f3777c - rustc_interface[e696fb279c73d43f]::passes::create_and_enter_global_ctxt::<core[e205c6c2c408574d]::option::Option<rustc_interface[e696fb279c73d43f]::queries::Linker>, rustc_driver_impl[44d86c3fd4736e11]::run_compiler::{closure#0}::{closure#2}>::{closure#2}::{closure#0}
  48:     0x772c75f282e0 - rustc_interface[e696fb279c73d43f]::interface::run_compiler::<(), rustc_driver_impl[44d86c3fd4736e11]::run_compiler::{closure#0}>::{closure#1}
  49:     0x772c75daedc8 - std[63ccf99907648090]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[e696fb279c73d43f]::util::run_in_thread_with_globals<rustc_interface[e696fb279c73d43f]::util::run_in_thread_pool_with_globals<rustc_interface[e696fb279c73d43f]::interface::run_compiler<(), rustc_driver_impl[44d86c3fd4736e11]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
  50:     0x772c75daf574 - <<std[63ccf99907648090]::thread::Builder>::spawn_unchecked_<rustc_interface[e696fb279c73d43f]::util::run_in_thread_with_globals<rustc_interface[e696fb279c73d43f]::util::run_in_thread_pool_with_globals<rustc_interface[e696fb279c73d43f]::interface::run_compiler<(), rustc_driver_impl[44d86c3fd4736e11]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[e205c6c2c408574d]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  51:     0x772c75db0a6f - std::sys::pal::unix::thread::Thread::new::thread_start::h8f2a48bb719a6902
  52:     0x772c6fea370a - <unknown>
  53:     0x772c6ff27aac - <unknown>
  54:                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: please attach the file at `/tmp/im/rustc-ice-2025-02-27T07_13_07-1226708.txt` to your bug report

query stack during panic:
#0 [adt_sized_constraint] computing the `Sized` constraint for `A`
#1 [evaluate_obligation] evaluating trait selection obligation `A: core::convert::Into<()>`
... and 2 other queries... use `env RUST_BACKTRACE=1` to see the full query stack
error: aborting due to 3 previous errors

Some errors have detailed explanations: E0063, E0601, E0658.
For more information about an error, try `rustc --explain E0063`.