ICE DefId does not have a "const_of_item" #148731
Description
auto-reduced (treereduce-rust):
//@compile-flags: -Zincremental-verify-ich=yes -Cincremental=<dir> -Cdebuginfo=2 -Clink-dead-code=true -Zvalidate-mir -Zquery-dep-graph -Zthreads=4 --edition=2024
#![feature(min_generic_const_args)]
pub trait Foo {}
impl Foo for [u8; std::path::MAIN_SEPARATOR] {}original:
// regression test for #133808.
#![allow(dead_code)]
#![feature(min_generic_const_args)]
#![allow(incomplete_features)]
#![crate_type = "lib"]
pub trait Foo {}
impl Foo for [u8; std::path::MAIN_SEPARATOR] {}
//~^ ERROR the constant `MAIN_SEPARATOR` is not of type `usize`Version information
rustc 1.93.0-nightly (acda5e9f9 2025-11-09)
binary: rustc
commit-hash: acda5e9f9aadac705b851935b14aa3d34a67d428
commit-date: 2025-11-09
host: x86_64-unknown-linux-gnu
release: 1.93.0-nightly
LLVM version: 21.1.3
Possibly related line of code:
rust/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
Lines 218 to 230 in acda5e9
Command:
/home/matthias/.rustup/toolchains/master/bin/rustc -Zincremental-verify-ich=yes -Cincremental=<dir> -Cdebuginfo=2 -Clink-dead-code=true -Zvalidate-mir -Zquery-dep-graph -Zthreads=4 --edition=2024
Program output
warning: the feature `min_generic_const_args` is incomplete and may not be safe to use and/or cause compiler crashes
--> /tmp/icemaker_global_tempdir.lw7Ljes8uH6W/rustc_testrunner_tmpdir_reporting.Iw1HM8tcwzkj/mvce.rs:1:12
|
1 | #![feature(min_generic_const_args)]
| ^^^^^^^^^^^^^^^^^^^^^^
|
= note: see issue #132980 <https://github.com/rust-lang/rust/issues/132980> for more information
= note: `#[warn(incomplete_features)]` on by default
error[E0601]: `main` function not found in crate `mvce`
--> /tmp/icemaker_global_tempdir.lw7Ljes8uH6W/rustc_testrunner_tmpdir_reporting.Iw1HM8tcwzkj/mvce.rs:4:48
|
4 | impl Foo for [u8; std::path::MAIN_SEPARATOR] {}
| ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.lw7Ljes8uH6W/rustc_testrunner_tmpdir_reporting.Iw1HM8tcwzkj/mvce.rs`
thread 'rustc' (2141391) panicked at compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs:224:1:
DefId(1:5606 ~ std[b4c0]::path::MAIN_SEPARATOR) does not have a "const_of_item"
stack backtrace:
0: 0x7ffaa066c9c3 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::h0dc93c2810c40bd0
1: 0x7ffaa0e01afc - core::fmt::write::hacdaf2bbd154e9b5
2: 0x7ffaa0621533 - std::io::Write::write_fmt::h75e948926e9dfbe3
3: 0x7ffaa0632b42 - std::sys::backtrace::BacktraceLock::print::h251013828edeee18
4: 0x7ffaa0638b99 - std::panicking::default_hook::{{closure}}::hf6c9462acd913055
5: 0x7ffaa06386c3 - std::panicking::default_hook::h4c9fd5029d2f8b73
6: 0x7ffa9f62a721 - std[b4c06921f787550c]::panicking::update_hook::<alloc[7ed4a9fe7ec582b8]::boxed::Box<rustc_driver_impl[87c4f5c8377f9862]::install_ice_hook::{closure#1}>>::{closure#0}
7: 0x7ffaa0638fbf - std::panicking::panic_with_hook::h02a757165762df79
8: 0x7ffaa0638d7a - std::panicking::panic_handler::{{closure}}::h66210c1b0223aa50
9: 0x7ffaa0632c79 - std::sys::backtrace::__rust_end_short_backtrace::h24c6c4da1001b922
10: 0x7ffaa061387d - __rustc[90cdb7b664da1e1e]::rust_begin_unwind
11: 0x7ffa9d6ba730 - core::panicking::panic_fmt::hb5559fbca70a856c
12: 0x7ffa9fbbc1a2 - rustc_metadata[cb4a4348587efc7]::rmeta::decoder::cstore_impl::provide_extern::const_of_item::{closure#2}
13: 0x7ffa9fbc7f6c - rustc_metadata[cb4a4348587efc7]::rmeta::decoder::cstore_impl::provide_extern::const_of_item
14: 0x7ffaa000b78b - rustc_query_impl[d4db0883806fa552]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[d4db0883806fa552]::query_impl::const_of_item::dynamic_query::{closure#2}::{closure#0}, rustc_middle[1e1513fa521466b3]::query::erase::Erased<[u8; 8usize]>>
15: 0x7ffaa12687c1 - rustc_query_system[d03d33f2f2d15895]::query::plumbing::try_execute_query::<rustc_query_impl[d4db0883806fa552]::DynamicConfig<rustc_query_system[d03d33f2f2d15895]::query::caches::DefIdCache<rustc_middle[1e1513fa521466b3]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[d4db0883806fa552]::plumbing::QueryCtxt, true>
16: 0x7ffaa00a56b7 - rustc_query_impl[d4db0883806fa552]::query_impl::const_of_item::get_query_incr::__rust_end_short_backtrace
17: 0x7ffaa226cbdd - <rustc_trait_selection[bb82b8f413fd2a2a]::traits::normalize::AssocTypeNormalizer>::normalize_free_alias::{closure#0}
18: 0x7ffaa10215aa - <rustc_trait_selection[bb82b8f413fd2a2a]::traits::normalize::AssocTypeNormalizer as rustc_type_ir[a0e454d4d0a700c1]::fold::TypeFolder<rustc_middle[1e1513fa521466b3]::ty::context::TyCtxt>>::fold_const
19: 0x7ffaa1023bd7 - <rustc_middle[1e1513fa521466b3]::ty::Ty as rustc_type_ir[a0e454d4d0a700c1]::fold::TypeSuperFoldable<rustc_middle[1e1513fa521466b3]::ty::context::TyCtxt>>::super_fold_with::<rustc_trait_selection[bb82b8f413fd2a2a]::traits::normalize::AssocTypeNormalizer>
20: 0x7ffaa14878c4 - <&rustc_middle[1e1513fa521466b3]::ty::list::RawList<(), rustc_middle[1e1513fa521466b3]::ty::generic_args::GenericArg> as rustc_type_ir[a0e454d4d0a700c1]::fold::TypeFoldable<rustc_middle[1e1513fa521466b3]::ty::context::TyCtxt>>::fold_with::<rustc_trait_selection[bb82b8f413fd2a2a]::traits::normalize::AssocTypeNormalizer>
21: 0x7ffaa170f603 - rustc_trait_selection[bb82b8f413fd2a2a]::traits::normalize::normalize_with_depth_to::<rustc_type_ir[a0e454d4d0a700c1]::predicate::TraitRef<rustc_middle[1e1513fa521466b3]::ty::context::TyCtxt>>::{closure#0}
22: 0x7ffaa17101b1 - rustc_hir_analysis[3bbcf63e422e422d]::check::wfcheck::check_impl
23: 0x7ffaa160ef37 - rustc_hir_analysis[3bbcf63e422e422d]::check::check::check_item_type
24: 0x7ffaa160c41c - rustc_hir_analysis[3bbcf63e422e422d]::check::wfcheck::check_well_formed
25: 0x7ffaa160c3f5 - rustc_query_impl[d4db0883806fa552]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[d4db0883806fa552]::query_impl::check_well_formed::dynamic_query::{closure#2}::{closure#0}, rustc_middle[1e1513fa521466b3]::query::erase::Erased<[u8; 1usize]>>
26: 0x7ffaa0f05c21 - rustc_query_system[d03d33f2f2d15895]::query::plumbing::try_execute_query::<rustc_query_impl[d4db0883806fa552]::DynamicConfig<rustc_data_structures[aff1d8a073485c2a]::vec_cache::VecCache<rustc_span[39972e28049286de]::def_id::LocalDefId, rustc_middle[1e1513fa521466b3]::query::erase::Erased<[u8; 1usize]>, rustc_query_system[d03d33f2f2d15895]::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl[d4db0883806fa552]::plumbing::QueryCtxt, true>
27: 0x7ffaa0f03f6d - rustc_query_impl[d4db0883806fa552]::query_impl::check_well_formed::get_query_incr::__rust_end_short_backtrace
28: 0x7ffa9f75682b - rustc_middle[1e1513fa521466b3]::query::inner::query_ensure_error_guaranteed::<rustc_data_structures[aff1d8a073485c2a]::vec_cache::VecCache<rustc_span[39972e28049286de]::def_id::LocalDefId, rustc_middle[1e1513fa521466b3]::query::erase::Erased<[u8; 1usize]>, rustc_query_system[d03d33f2f2d15895]::dep_graph::graph::DepNodeIndex>, ()>
29: 0x7ffa9f76727e - rustc_data_structures[aff1d8a073485c2a]::sync::parallel::par_slice::par_rec::<&rustc_hir[2565f01ea710f611]::hir::ItemId, rustc_data_structures[aff1d8a073485c2a]::sync::parallel::try_par_for_each_in<&[rustc_hir[2565f01ea710f611]::hir::ItemId], rustc_span[39972e28049286de]::ErrorGuaranteed, <rustc_middle[1e1513fa521466b3]::hir::ModuleItems>::par_items<rustc_hir_analysis[3bbcf63e422e422d]::check::wfcheck::check_type_wf::{closure#0}>::{closure#0}>::{closure#0}::{closure#0}>
30: 0x7ffa9f7a0644 - rustc_thread_pool[80e8a9b643659d2e]::join::join_context::<rustc_thread_pool[80e8a9b643659d2e]::join::join::call<(), rustc_data_structures[aff1d8a073485c2a]::sync::parallel::par_slice::par_rec<&rustc_hir[2565f01ea710f611]::hir::ItemId, rustc_data_structures[aff1d8a073485c2a]::sync::parallel::try_par_for_each_in<&[rustc_hir[2565f01ea710f611]::hir::ItemId], rustc_span[39972e28049286de]::ErrorGuaranteed, <rustc_middle[1e1513fa521466b3]::hir::ModuleItems>::par_items<rustc_hir_analysis[3bbcf63e422e422d]::check::wfcheck::check_type_wf::{closure#0}>::{closure#0}>::{closure#0}::{closure#0}>::{closure#1}>::{closure#0}, rustc_thread_pool[80e8a9b643659d2e]::join::join::call<(), rustc_data_structures[aff1d8a073485c2a]::sync::parallel::par_slice::par_rec<&rustc_hir[2565f01ea710f611]::hir::ItemId, rustc_data_structures[aff1d8a073485c2a]::sync::parallel::try_par_for_each_in<&[rustc_hir[2565f01ea710f611]::hir::ItemId], rustc_span[39972e28049286de]::ErrorGuaranteed, <rustc_middle[1e1513fa521466b3]::hir::ModuleItems>::par_items<rustc_hir_analysis[3bbcf63e422e422d]::check::wfcheck::check_type_wf::{closure#0}>::{closure#0}>::{closure#0}::{closure#0}>::{closure#2}>::{closure#0}, (), ()>::{closure#0}
31: 0x7ffa9f767325 - rustc_data_structures[aff1d8a073485c2a]::sync::parallel::par_slice::par_rec::<&rustc_hir[2565f01ea710f611]::hir::ItemId, rustc_data_structures[aff1d8a073485c2a]::sync::parallel::try_par_for_each_in<&[rustc_hir[2565f01ea710f611]::hir::ItemId], rustc_span[39972e28049286de]::ErrorGuaranteed, <rustc_middle[1e1513fa521466b3]::hir::ModuleItems>::par_items<rustc_hir_analysis[3bbcf63e422e422d]::check::wfcheck::check_type_wf::{closure#0}>::{closure#0}>::{closure#0}::{closure#0}>
32: 0x7ffa9f829b37 - <rustc_thread_pool[80e8a9b643659d2e]::job::StackJob<rustc_thread_pool[80e8a9b643659d2e]::latch::SpinLatch, rustc_thread_pool[80e8a9b643659d2e]::join::join_context<rustc_thread_pool[80e8a9b643659d2e]::join::join::call<(), rustc_data_structures[aff1d8a073485c2a]::sync::parallel::par_slice::par_rec<&rustc_hir[2565f01ea710f611]::hir::ItemId, rustc_data_structures[aff1d8a073485c2a]::sync::parallel::try_par_for_each_in<&[rustc_hir[2565f01ea710f611]::hir::ItemId], rustc_span[39972e28049286de]::ErrorGuaranteed, <rustc_middle[1e1513fa521466b3]::hir::ModuleItems>::par_items<rustc_hir_analysis[3bbcf63e422e422d]::check::wfcheck::check_type_wf::{closure#0}>::{closure#0}>::{closure#0}::{closure#0}>::{closure#1}>::{closure#0}, rustc_thread_pool[80e8a9b643659d2e]::join::join::call<(), rustc_data_structures[aff1d8a073485c2a]::sync::parallel::par_slice::par_rec<&rustc_hir[2565f01ea710f611]::hir::ItemId, rustc_data_structures[aff1d8a073485c2a]::sync::parallel::try_par_for_each_in<&[rustc_hir[2565f01ea710f611]::hir::ItemId], rustc_span[39972e28049286de]::ErrorGuaranteed, <rustc_middle[1e1513fa521466b3]::hir::ModuleItems>::par_items<rustc_hir_analysis[3bbcf63e422e422d]::check::wfcheck::check_type_wf::{closure#0}>::{closure#0}>::{closure#0}::{closure#0}>::{closure#2}>::{closure#0}, (), ()>::{closure#0}::{closure#0}, ()> as rustc_thread_pool[80e8a9b643659d2e]::job::Job>::execute
33: 0x7ffaa034362f - <rustc_thread_pool[80e8a9b643659d2e]::registry::WorkerThread>::wait_or_steal_until_cold
34: 0x7ffaa03420d1 - <rustc_thread_pool[80e8a9b643659d2e]::registry::ThreadBuilder>::run
35: 0x7ffa9f62284d - std[b4c06921f787550c]::sys::backtrace::__rust_begin_short_backtrace::<<rustc_thread_pool[80e8a9b643659d2e]::ThreadPoolBuilder>::build_scoped<rustc_interface[df9ddd9c9467ef8b]::util::run_in_thread_pool_with_globals<rustc_interface[df9ddd9c9467ef8b]::interface::run_compiler<(), rustc_driver_impl[87c4f5c8377f9862]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#5}::{closure#0}::{closure#0}, rustc_interface[df9ddd9c9467ef8b]::util::run_in_thread_pool_with_globals<rustc_interface[df9ddd9c9467ef8b]::interface::run_compiler<(), rustc_driver_impl[87c4f5c8377f9862]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#5}::{closure#0}::{closure#1}, ()>::{closure#0}::{closure#0}::{closure#0}, ()>
36: 0x7ffa9f62dd52 - <<std[b4c06921f787550c]::thread::Builder>::spawn_unchecked_<<rustc_thread_pool[80e8a9b643659d2e]::ThreadPoolBuilder>::build_scoped<rustc_interface[df9ddd9c9467ef8b]::util::run_in_thread_pool_with_globals<rustc_interface[df9ddd9c9467ef8b]::interface::run_compiler<(), rustc_driver_impl[87c4f5c8377f9862]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#5}::{closure#0}::{closure#0}, rustc_interface[df9ddd9c9467ef8b]::util::run_in_thread_pool_with_globals<rustc_interface[df9ddd9c9467ef8b]::interface::run_compiler<(), rustc_driver_impl[87c4f5c8377f9862]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#5}::{closure#0}::{closure#1}, ()>::{closure#0}::{closure#0}::{closure#0}, ()>::{closure#1} as core[f1f7c8de62d6692e]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
37: 0x7ffaa1c8afef - std::sys::thread::unix::Thread::new::thread_start::h6ee5f4a2e2de181d
38: 0x7ffa9b6969cb - <unknown>
39: 0x7ffa9b71aa0c - <unknown>
40: 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: rustc 1.93.0-nightly (acda5e9f9 2025-11-09) running on x86_64-unknown-linux-gnu
note: compiler flags: -Z incremental-verify-ich=yes -C incremental=[REDACTED] -C debuginfo=2 -C link-dead-code=true -Z validate-mir -Z query-dep-graph -Z threads=4
query stack during panic:
#0 [const_of_item] computing the type-level value for `std::path::MAIN_SEPARATOR`
#1 [check_well_formed] checking that `<impl at /tmp/icemaker_global_tempdir.lw7Ljes8uH6W/rustc_testrunner_tmpdir_reporting.Iw1HM8tcwzkj/mvce.rs:4:1: 4:45>` is well-formed
#2 [check_type_wf] checking that types are well-formed
#3 [analysis] running analysis passes on crate `mvce`
end of query stack
error: aborting due to 1 previous error; 1 warning emitted
For more information about this error, try `rustc --explain E0601`.
@rustbot label +F-min_generic_const_args +-Zvalidate-mir