[ICE]: `invalid pointer unsizing &i32 -> i32`
Open
Nobody has claimed this yet.
C-bug
F-coerce_unsized
I-ICE
T-compiler
WG-trait-system-refactor
- Dominant language
- Rust
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Description
auto-reduced (treereduce-rust):
//@compile-flags: -Znext-solver=globally
#![feature(coerce_unsized)]
impl<A> std::ops::CoerceUnsized<A> for A {}
pub fn f() {
[0; {
let mut c = &0;
c = &0;
0
}]
}
original:
#![feature(feature)]
#![crate_type = "lib"]
impl<A> std::ops::CoerceUnsized<A> for A {}
pub fn f() {
[0; {
let mut c = &0;
c = &0;
0
}]
}
Version information
rustc 1.95.0-nightly (621d76794 2026-01-18)
binary: rustc
commit-hash: 621d76794c76fc21c0a6151fbc090120e0230a91
commit-date: 2026-01-18
host: x86_64-unknown-linux-gnu
release: 1.95.0-nightly
LLVM version: 21.1.8
Possibly related line of code:
https://github.com/rust-lang/rust/blob/621d76794c76fc21c0a6151fbc090120e0230a91/compiler/rustc_const_eval/src/interpret/cast.rs#L445-L457
Command:
/home/matthias/.rustup/toolchains/master/bin/rustc -Znext-solver=globally
Program output
error[E0601]: `main` function not found in crate `mvce`
--> /tmp/icemaker_global_tempdir.knP2pWc932nn/rustc_testrunner_tmpdir_reporting.wByzSCkn0iNO/mvce.rs:8:2
|
8 | }
| ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.knP2pWc932nn/rustc_testrunner_tmpdir_reporting.wByzSCkn0iNO/mvce.rs`
error[E0658]: use of unstable library feature `coerce_unsized`
--> /tmp/icemaker_global_tempdir.knP2pWc932nn/rustc_testrunner_tmpdir_reporting.wByzSCkn0iNO/mvce.rs:1:9
|
1 | impl<A> std::ops::CoerceUnsized<A> for A {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: see issue #18598 <https://github.com/rust-lang/rust/issues/18598> for more information
= help: add `#![feature(coerce_unsized)]` to the crate attributes to enable
= note: this compiler was built on 2026-01-18; consider upgrading it if it is out of date
error[E0210]: type parameter `A` must be used as the type parameter for some local type (e.g., `MyStruct<A>`)
--> /tmp/icemaker_global_tempdir.knP2pWc932nn/rustc_testrunner_tmpdir_reporting.wByzSCkn0iNO/mvce.rs:1:6
|
1 | impl<A> std::ops::CoerceUnsized<A> for A {}
| ^ type parameter `A` must be used as the type parameter for some local type
|
= note: implementing a foreign trait is only possible if at least one of the types for which it is implemented is local
= note: only traits defined in the current crate can be implemented for a type parameter
error[E0377]: the trait `CoerceUnsized` may only be implemented for a coercion between structures
--> /tmp/icemaker_global_tempdir.knP2pWc932nn/rustc_testrunner_tmpdir_reporting.wByzSCkn0iNO/mvce.rs:1:1
|
1 | impl<A> std::ops::CoerceUnsized<A> for A {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
warning: variable `c` is assigned to, but never used
--> /tmp/icemaker_global_tempdir.knP2pWc932nn/rustc_testrunner_tmpdir_reporting.wByzSCkn0iNO/mvce.rs:4:13
|
4 | let mut c = &0;
| ^^^^^
|
= note: consider using `_c` instead
= note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
warning: value assigned to `c` is never read
--> /tmp/icemaker_global_tempdir.knP2pWc932nn/rustc_testrunner_tmpdir_reporting.wByzSCkn0iNO/mvce.rs:5:9
|
5 | c = &0;
| ^^^^^^
|
= help: maybe it is overwritten before being read?
= note: `#[warn(unused_assignments)]` (part of `#[warn(unused)]`) on by default
error: internal compiler error: /rustc-dev/621d76794c76fc21c0a6151fbc090120e0230a91/compiler/rustc_const_eval/src/interpret/cast.rs:451:17: invalid pointer unsizing &i32 -> i32
--> /tmp/icemaker_global_tempdir.knP2pWc932nn/rustc_testrunner_tmpdir_reporting.wByzSCkn0iNO/mvce.rs:5:9
|
5 | c = &0;
| ^^^^^^
thread 'rustc' (1142729) panicked at /rustc-dev/621d76794c76fc21c0a6151fbc090120e0230a91/compiler/rustc_const_eval/src/interpret/cast.rs:451:17:
Box<dyn Any>
stack backtrace:
0: 0x7fa8ae833fd3 - <<std[287527946f71f0bc]::sys::backtrace::BacktraceLock>::print::DisplayBacktrace as core[7477a31a1a34cc49]::fmt::Display>::fmt
1: 0x7fa8aee0e2c8 - core[7477a31a1a34cc49]::fmt::write
2: 0x7fa8ae84a9c6 - <std[287527946f71f0bc]::sys::stdio::unix::Stderr as std[287527946f71f0bc]::io::Write>::write_fmt
3: 0x7fa8ae80a048 - std[287527946f71f0bc]::panicking::default_hook::{closure#0}
4: 0x7fa8ae827703 - std[287527946f71f0bc]::panicking::default_hook
5: 0x7fa8ad7fbb8a - std[287527946f71f0bc]::panicking::update_hook::<alloc[979041e9952e771b]::boxed::Box<rustc_driver_impl[517260a07841a630]::install_ice_hook::{closure#1}>>::{closure#0}
6: 0x7fa8ae8279e2 - std[287527946f71f0bc]::panicking::panic_with_hook
7: 0x7fa8ad838bc1 - std[287527946f71f0bc]::panicking::begin_panic::<rustc_errors[26c9ea40265c581b]::ExplicitBug>::{closure#0}
8: 0x7fa8ad828fe6 - std[287527946f71f0bc]::sys::backtrace::__rust_end_short_backtrace::<std[287527946f71f0bc]::panicking::begin_panic<rustc_errors[26c9ea40265c581b]::ExplicitBug>::{closure#0}, !>
9: 0x7fa8ad8264b9 - std[287527946f71f0bc]::panicking::begin_panic::<rustc_errors[26c9ea40265c581b]::ExplicitBug>
10: 0x7fa8ad856901 - <rustc_errors[26c9ea40265c581b]::diagnostic::BugAbort as rustc_errors[26c9ea40265c581b]::diagnostic::EmissionGuarantee>::emit_producing_guarantee
11: 0x7fa8adde492c - <rustc_errors[26c9ea40265c581b]::DiagCtxtHandle>::span_bug::<rustc_span[851f35e07e3c2dd4]::span_encoding::Span, alloc[979041e9952e771b]::string::String>
12: 0x7fa8ade074d6 - rustc_middle[725063e074f29df]::util::bug::opt_span_bug_fmt::<rustc_span[851f35e07e3c2dd4]::span_encoding::Span>::{closure#0}
13: 0x7fa8ade07682 - rustc_middle[725063e074f29df]::ty::context::tls::with_opt::<rustc_middle[725063e074f29df]::util::bug::opt_span_bug_fmt<rustc_span[851f35e07e3c2dd4]::span_encoding::Span>::{closure#0}, !>::{closure#0}
14: 0x7fa8addf8cab - rustc_middle[725063e074f29df]::ty::context::tls::with_context_opt::<rustc_middle[725063e074f29df]::ty::context::tls::with_opt<rustc_middle[725063e074f29df]::util::bug::opt_span_bug_fmt<rustc_span[851f35e07e3c2dd4]::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
15: 0x7fa8ab6afa68 - rustc_middle[725063e074f29df]::util::bug::span_bug_fmt::<rustc_span[851f35e07e3c2dd4]::span_encoding::Span>
16: 0x7fa8af39d5aa - <rustc_const_eval[b948c5b36ae67fb9]::interpret::eval_context::InterpCx<rustc_const_eval[b948c5b36ae67fb9]::const_eval::machine::CompileTimeMachine>>::unsize_into_ptr::<rustc_const_eval[b948c5b36ae67fb9]::interpret::place::PlaceTy>
17: 0x7fa8aff00904 - <rustc_const_eval[b948c5b36ae67fb9]::interpret::eval_context::InterpCx<rustc_const_eval[b948c5b36ae67fb9]::const_eval::machine::CompileTimeMachine>>::eval_rvalue_into_place
18: 0x7fa8afeba0cd - rustc_const_eval[b948c5b36ae67fb9]::const_eval::eval_queries::eval_to_allocation_raw_provider
19: 0x7fa8afeb847e - rustc_query_impl[f20b8284200e680a]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[f20b8284200e680a]::query_impl::eval_to_allocation_raw::dynamic_query::{closure#2}::{closure#0}, rustc_middle[725063e074f29df]::query::erase::Erased<[u8; 24usize]>>
20: 0x7fa8afeb7ba5 - rustc_query_system[b7e73caa2c2ad9a]::query::plumbing::try_execute_query::<rustc_query_impl[f20b8284200e680a]::DynamicConfig<rustc_query_system[b7e73caa2c2ad9a]::query::caches::DefaultCache<rustc_middle[725063e074f29df]::ty::PseudoCanonicalInput<rustc_middle[725063e074f29df]::mir::interpret::GlobalId>, rustc_middle[725063e074f29df]::query::erase::Erased<[u8; 24usize]>>, false, false, false>, rustc_query_impl[f20b8284200e680a]::plumbing::QueryCtxt, false>
21: 0x7fa8afeb7749 - rustc_query_impl[f20b8284200e680a]::query_impl::eval_to_allocation_raw::get_query_non_incr::__rust_end_short_backtrace
22: 0x7fa8afea0a02 - rustc_const_eval[b948c5b36ae67fb9]::const_eval::valtrees::eval_to_valtree
23: 0x7fa8afea07b6 - <rustc_const_eval[b948c5b36ae67fb9]::provide::{closure#0} as core[7477a31a1a34cc49]::ops::function::FnOnce<(rustc_middle[725063e074f29df]::ty::context::TyCtxt, rustc_middle[725063e074f29df]::ty::PseudoCanonicalInput<rustc_middle[725063e074f29df]::mir::interpret::GlobalId>)>>::call_once
24: 0x7fa8afea0780 - rustc_query_impl[f20b8284200e680a]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[f20b8284200e680a]::query_impl::eval_to_valtree::dynamic_query::{closure#2}::{closure#0}, rustc_middle[725063e074f29df]::query::erase::Erased<[u8; 16usize]>>
25: 0x7fa8afea073b - <rustc_query_impl[f20b8284200e680a]::query_impl::eval_to_valtree::dynamic_query::{closure#2} as core[7477a31a1a34cc49]::ops::function::FnOnce<(rustc_middle[725063e074f29df]::ty::context::TyCtxt, rustc_middle[725063e074f29df]::ty::PseudoCanonicalInput<rustc_middle[725063e074f29df]::mir::interpret::GlobalId>)>>::call_once
26: 0x7fa8af92f7c6 - rustc_query_system[b7e73caa2c2ad9a]::query::plumbing::try_execute_query::<rustc_query_impl[f20b8284200e680a]::DynamicConfig<rustc_query_system[b7e73caa2c2ad9a]::query::caches::DefaultCache<rustc_middle[725063e074f29df]::ty::PseudoCanonicalInput<rustc_middle[725063e074f29df]::mir::interpret::GlobalId>, rustc_middle[725063e074f29df]::query::erase::Erased<[u8; 16usize]>>, false, false, false>, rustc_query_impl[f20b8284200e680a]::plumbing::QueryCtxt, false>
27: 0x7fa8af92f3f0 - rustc_query_impl[f20b8284200e680a]::query_impl::eval_to_valtree::get_query_non_incr::__rust_end_short_backtrace
28: 0x7fa8abb581b9 - <rustc_middle[725063e074f29df]::ty::context::TyCtxt>::const_eval_resolve_for_typeck
29: 0x7fa8af06d2e4 - rustc_trait_selection[9fee51d8a10a777c]::traits::try_evaluate_const
30: 0x7fa8b004ab56 - <rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate as rustc_next_trait_solver[2bc6883c9be4be93]::delegate::SolverDelegate>::evaluate_const
31: 0x7fa8afd52070 - <rustc_next_trait_solver[2bc6883c9be4be93]::solve::search_graph::SearchGraphDelegate<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate> as rustc_type_ir[b93cf349b3a4f34d]::search_graph::Delegate>::compute_goal::{closure#0}
32: 0x7fa8afd5038f - <rustc_type_ir[b93cf349b3a4f34d]::search_graph::SearchGraph<rustc_next_trait_solver[2bc6883c9be4be93]::solve::search_graph::SearchGraphDelegate<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate>, rustc_middle[725063e074f29df]::ty::context::TyCtxt>>::evaluate_goal::{closure#0}::{closure#2}
33: 0x7fa8afa08b45 - <rustc_next_trait_solver[2bc6883c9be4be93]::solve::eval_ctxt::EvalCtxt<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate, rustc_middle[725063e074f29df]::ty::context::TyCtxt>>::evaluate_goal_raw
34: 0x7fa8afa2ce0a - <rustc_next_trait_solver[2bc6883c9be4be93]::solve::eval_ctxt::EvalCtxt<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate, rustc_middle[725063e074f29df]::ty::context::TyCtxt>>::try_evaluate_added_goals
35: 0x7fa8afd51674 - <rustc_next_trait_solver[2bc6883c9be4be93]::solve::search_graph::SearchGraphDelegate<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate> as rustc_type_ir[b93cf349b3a4f34d]::search_graph::Delegate>::compute_goal::{closure#0}
36: 0x7fa8afd5038f - <rustc_type_ir[b93cf349b3a4f34d]::search_graph::SearchGraph<rustc_next_trait_solver[2bc6883c9be4be93]::solve::search_graph::SearchGraphDelegate<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate>, rustc_middle[725063e074f29df]::ty::context::TyCtxt>>::evaluate_goal::{closure#0}::{closure#2}
37: 0x7fa8afa08b45 - <rustc_next_trait_solver[2bc6883c9be4be93]::solve::eval_ctxt::EvalCtxt<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate, rustc_middle[725063e074f29df]::ty::context::TyCtxt>>::evaluate_goal_raw
38: 0x7fa8afa2ca8d - <rustc_next_trait_solver[2bc6883c9be4be93]::solve::eval_ctxt::EvalCtxt<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate, rustc_middle[725063e074f29df]::ty::context::TyCtxt>>::try_evaluate_added_goals
39: 0x7fa8afa171f1 - <rustc_next_trait_solver[2bc6883c9be4be93]::solve::eval_ctxt::EvalCtxt<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate, rustc_middle[725063e074f29df]::ty::context::TyCtxt>>::evaluate_added_goals_and_make_canonical_response
40: 0x7fa8afd513b4 - <rustc_next_trait_solver[2bc6883c9be4be93]::solve::search_graph::SearchGraphDelegate<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate> as rustc_type_ir[b93cf349b3a4f34d]::search_graph::Delegate>::compute_goal::{closure#0}
41: 0x7fa8afd5038f - <rustc_type_ir[b93cf349b3a4f34d]::search_graph::SearchGraph<rustc_next_trait_solver[2bc6883c9be4be93]::solve::search_graph::SearchGraphDelegate<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate>, rustc_middle[725063e074f29df]::ty::context::TyCtxt>>::evaluate_goal::{closure#0}::{closure#2}
42: 0x7fa8afa08b45 - <rustc_next_trait_solver[2bc6883c9be4be93]::solve::eval_ctxt::EvalCtxt<rustc_trait_selection[9fee51d8a10a777c]::solve::delegate::SolverDelegate, rustc_middle[725063e074f29df]::ty::context::TyCtxt>>::evaluate_goal_raw
43: 0x7fa8afa29011 - <rustc_trait_selection[9fee51d8a10a777c]::solve::fulfill::FulfillmentCtxt<rustc_trait_selection[9fee51d8a10a777c]::traits::FulfillmentError> as rustc_infer[5a785d1c27494969]::traits::engine::TraitEngine<rustc_trait_selection[9fee51d8a10a777c]::traits::FulfillmentError>>::try_evaluate_obligations
44: 0x7fa8affae12f - <rustc_infer[5a785d1c27494969]::infer::at::At as rustc_trait_selection[9fee51d8a10a777c]::traits::structural_normalize::StructurallyNormalizeExt>::structurally_normalize_term::<rustc_trait_selection[9fee51d8a10a777c]::traits::FulfillmentError>
45: 0x7fa8affae9b9 - <rustc_hir_typeck[ed5453188701a25b]::fn_ctxt::FnCtxt>::try_structurally_resolve_const
46: 0x7fa8affaecb7 - <rustc_hir_typeck[ed5453188701a25b]::fn_ctxt::FnCtxt>::check_expr_repeat
47: 0x7fa8af21b5d2 - <rustc_hir_typeck[ed5453188701a25b]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
48: 0x7fa8af213dbb - <rustc_hir_typeck[ed5453188701a25b]::fn_ctxt::FnCtxt>::check_expr_block
49: 0x7fa8af21998b - <rustc_hir_typeck[ed5453188701a25b]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
50: 0x7fa8af1fa1a6 - rustc_hir_typeck[ed5453188701a25b]::check::check_fn
51: 0x7fa8afbb3d33 - rustc_hir_typeck[ed5453188701a25b]::typeck_with_inspect::{closure#0}
52: 0x7fa8afbb26b4 - rustc_query_impl[f20b8284200e680a]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[f20b8284200e680a]::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle[725063e074f29df]::query::erase::Erased<[u8; 8usize]>>
53: 0x7fa8aef5522a - rustc_query_system[b7e73caa2c2ad9a]::query::plumbing::try_execute_query::<rustc_query_impl[f20b8284200e680a]::DynamicConfig<rustc_data_structures[e0d8483206daafa2]::vec_cache::VecCache<rustc_span[851f35e07e3c2dd4]::def_id::LocalDefId, rustc_middle[725063e074f29df]::query::erase::Erased<[u8; 8usize]>, rustc_query_system[b7e73caa2c2ad9a]::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl[f20b8284200e680a]::plumbing::QueryCtxt, false>
54: 0x7fa8aef54b09 - rustc_query_impl[f20b8284200e680a]::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
55: 0x7fa8af93fdb5 - <rustc_middle[725063e074f29df]::ty::context::TyCtxt>::par_hir_body_owners::<rustc_hir_analysis[1a80394817eddfdd]::check_crate::{closure#2}>::{closure#0}
56: 0x7fa8af93f7c4 - rustc_hir_analysis[1a80394817eddfdd]::check_crate
57: 0x7fa8aef493db - rustc_interface[5c48368f5debe80d]::passes::analysis
58: 0x7fa8aef49035 - rustc_query_impl[f20b8284200e680a]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[f20b8284200e680a]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[725063e074f29df]::query::erase::Erased<[u8; 0usize]>>
59: 0x7fa8affa4be3 - rustc_query_system[b7e73caa2c2ad9a]::query::plumbing::try_execute_query::<rustc_query_impl[f20b8284200e680a]::DynamicConfig<rustc_query_system[b7e73caa2c2ad9a]::query::caches::SingleCache<rustc_middle[725063e074f29df]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[f20b8284200e680a]::plumbing::QueryCtxt, false>
60: 0x7fa8affa49ce - rustc_query_impl[f20b8284200e680a]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
61: 0x7fa8b0182c11 - <rustc_interface[5c48368f5debe80d]::passes::create_and_enter_global_ctxt<core[7477a31a1a34cc49]::option::Option<rustc_interface[5c48368f5debe80d]::queries::Linker>, rustc_driver_impl[517260a07841a630]::run_compiler::{closure#0}::{closure#2}>::{closure#2} as core[7477a31a1a34cc49]::ops::function::FnOnce<(&rustc_session[eb79e6d3104f29ae]::session::Session, rustc_middle[725063e074f29df]::ty::context::CurrentGcx, alloc[979041e9952e771b]::sync::Arc<rustc_data_structures[e0d8483206daafa2]::jobserver::Proxy>, &std[287527946f71f0bc]::sync::once_lock::OnceLock<rustc_middle[725063e074f29df]::ty::context::GlobalCtxt>, &rustc_data_structures[e0d8483206daafa2]::sync::worker_local::WorkerLocal<rustc_middle[725063e074f29df]::arena::Arena>, &rustc_data_structures[e0d8483206daafa2]::sync::worker_local::WorkerLocal<rustc_hir[7eac7792dedc1861]::Arena>, rustc_driver_impl[517260a07841a630]::run_compiler::{closure#0}::{closure#2})>>::call_once::{shim:vtable#0}
62: 0x7fa8afff5d34 - rustc_interface[5c48368f5debe80d]::interface::run_compiler::<(), rustc_driver_impl[517260a07841a630]::run_compiler::{closure#0}>::{closure#1}
63: 0x7fa8aff5aa3a - std[287527946f71f0bc]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[5c48368f5debe80d]::util::run_in_thread_with_globals<rustc_interface[5c48368f5debe80d]::util::run_in_thread_pool_with_globals<rustc_interface[5c48368f5debe80d]::interface::run_compiler<(), rustc_driver_impl[517260a07841a630]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
64: 0x7fa8aff5a7fe - <std[287527946f71f0bc]::thread::lifecycle::spawn_unchecked<rustc_interface[5c48368f5debe80d]::util::run_in_thread_with_globals<rustc_interface[5c48368f5debe80d]::util::run_in_thread_pool_with_globals<rustc_interface[5c48368f5debe80d]::interface::run_compiler<(), rustc_driver_impl[517260a07841a630]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[7477a31a1a34cc49]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
65: 0x7fa8aff5c5c4 - <std[287527946f71f0bc]::sys::thread::unix::Thread>::new::thread_start
66: 0x7fa8a989698b - <unknown>
67: 0x7fa8a991a9cc - <unknown>
68: 0x0 - <unknown>
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 1.95.0-nightly (621d76794 2026-01-18) running on x86_64-unknown-linux-gnu
note: compiler flags: -Z next-solver=globally -Z dump-mir-dir=dir
query stack during panic:
#0 [eval_to_allocation_raw] const-evaluating + checking `f::{constant#0}`
#1 [eval_to_valtree] evaluating type-level constant
#2 [typeck] type-checking `f`
#3 [analysis] running analysis passes on crate `mvce`
end of query stack
error: aborting due to 5 previous errors; 2 warnings emitted
Some errors have detailed explanations: E0210, E0377, E0601, E0658.
For more information about an error, try `rustc --explain E0210`.
@rustbot label +F-feature +WG-trait-system-refactor
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Reproduce the reduced Rust example with -Znext-solver=globally, then read compiler/rustc_const_eval/src/interpret/cast.rs around lines 445–457 and follow the unsize_into_ptr path shown in the backtrace. Done means this case no longer triggers the invalid-pointer-unsizing ICE and reports a normal compiler result; the issue does not name a regression test location.
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
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 48/100