ICE couldn't normalize struct field [u8; C] when checking Copy implementation #149066
Description
auto-reduced (treereduce-rust):
#![feature(min_generic_const_args)]
const C: usize = 16;
pub struct Foo([u8; C]);
fn main() {}original:
//@compile-flags: --crate-type lib
#![feature(repr_simd)]
const C: usize = 16;
#[feature(generic_const_exprs)]
pub struct Foo([u8; C]);
pub unsafe fn foo(a: Foo) {}
fn main() {}Version information
rustc 1.93.0-nightly (3d461af2a 2025-11-18)
binary: rustc
commit-hash: 3d461af2a23456a2676aadb13b4253c87bdfe28d
commit-date: 2025-11-18
host: x86_64-unknown-linux-gnu
release: 1.93.0-nightly
LLVM version: 21.1.5
Command:
/home/matthias/.rustup/toolchains/master/bin/rustc -Zcrate-attr=feature(min_generic_const_args)
Program output
warning: the feature `min_generic_const_args` is incomplete and may not be safe to use and/or cause compiler crashes
--> <crate attribute>: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
warning: 1 warning emitted
note: no errors encountered even though delayed bugs were created
note: those delayed bugs will now be shown as internal compiler errors
error: internal compiler error: cannot call const_of_item on a non-type_const
--> /tmp/icemaker_global_tempdir.tFJc9K91h3pp/rustc_testrunner_tmpdir_reporting.bcikJhNz0lr1/mvce.rs:1:1
|
1 | const C: usize = 16;
| ^^^^^^^^^^^^^^
|
note: delayed at compiler/rustc_hir_analysis/src/collect.rs:1615:31
0: <rustc_errors::DiagCtxtInner>::emit_diagnostic
1: <rustc_errors::DiagCtxtHandle>::emit_diagnostic
2: <rustc_span::ErrorGuaranteed as rustc_errors::diagnostic::EmissionGuarantee>::emit_producing_guarantee
3: <rustc_errors::DiagCtxtHandle>::span_delayed_bug::<rustc_span::span_encoding::Span, &str>
4: rustc_hir_analysis::collect::const_of_item
5: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::const_of_item::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
6: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefIdCache<rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
7: rustc_query_impl::query_impl::const_of_item::get_query_non_incr::__rust_end_short_backtrace
8: <rustc_trait_selection::traits::normalize::AssocTypeNormalizer>::normalize_free_alias::{closure#0}
9: <rustc_trait_selection::traits::normalize::AssocTypeNormalizer as rustc_type_ir::fold::TypeFolder<rustc_middle::ty::context::TyCtxt>>::fold_const
10: <rustc_middle::ty::Ty as rustc_type_ir::fold::TypeSuperFoldable<rustc_middle::ty::context::TyCtxt>>::super_fold_with::<rustc_trait_selection::traits::normalize::AssocTypeNormalizer>
11: <rustc_hir_analysis::check::wfcheck::WfCheckingCtxt>::deeply_normalize::<rustc_middle::ty::Ty>
12: rustc_hir_analysis::check::wfcheck::check_type_defn
13: rustc_hir_analysis::check::check::check_item_type
14: rustc_hir_analysis::check::wfcheck::check_well_formed
15: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_well_formed::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
16: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_data_structures::vec_cache::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 1]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
17: rustc_query_impl::query_impl::check_well_formed::get_query_non_incr::__rust_end_short_backtrace
18: rustc_hir_analysis::check::wfcheck::check_type_wf
19: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_type_wf::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
20: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 1]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
21: rustc_query_impl::query_impl::check_type_wf::get_query_non_incr::__rust_end_short_backtrace
22: rustc_hir_analysis::check_crate
23: rustc_interface::passes::analysis
24: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>
25: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 0]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
26: rustc_query_impl::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
27: <rustc_interface::passes::create_and_enter_global_ctxt<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>::{closure#2} as core::ops::function::FnOnce<(&rustc_session::session::Session, rustc_middle::ty::context::CurrentGcx, alloc::sync::Arc<rustc_data_structures::jobserver::Proxy>, &std::sync::once_lock::OnceLock<rustc_middle::ty::context::GlobalCtxt>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_middle::arena::Arena>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_hir::Arena>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2})>>::call_once::{shim:vtable#0}
28: rustc_interface::interface::run_compiler::<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}
29: std::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
30: <<std::thread::Builder>::spawn_unchecked_<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
31: std::sys::thread::unix::Thread::new::thread_start
32: <unknown>
33: <unknown>
--> /tmp/icemaker_global_tempdir.tFJc9K91h3pp/rustc_testrunner_tmpdir_reporting.bcikJhNz0lr1/mvce.rs:1:1
|
1 | const C: usize = 16;
| ^^^^^^^^^^^^^^
error: internal compiler error: couldn't normalize struct field `[u8; C]` when checking Copy implementation
--> /tmp/icemaker_global_tempdir.tFJc9K91h3pp/rustc_testrunner_tmpdir_reporting.bcikJhNz0lr1/mvce.rs:3:16
|
3 | pub struct Foo([u8; C]);
| ^^^^^^^
|
note: delayed at compiler/rustc_trait_selection/src/traits/misc.rs:245:27
0: <rustc_errors::DiagCtxtInner>::emit_diagnostic
1: <rustc_errors::DiagCtxtHandle>::emit_diagnostic
2: <rustc_span::ErrorGuaranteed as rustc_errors::diagnostic::EmissionGuarantee>::emit_producing_guarantee
3: <rustc_errors::DiagCtxtHandle>::span_delayed_bug::<rustc_span::span_encoding::Span, alloc::string::String>
4: rustc_trait_selection::traits::misc::all_fields_implement_trait
5: rustc_trait_selection::traits::misc::type_allowed_to_implement_copy
6: <rustc_lint::builtin::MissingCopyImplementations as rustc_lint::passes::LateLintPass>::check_item
7: <rustc_lint::BuiltinCombinedModuleLateLintPass as rustc_lint::passes::LateLintPass>::check_item
8: <rustc_lint::late::LateContextAndPass<rustc_lint::BuiltinCombinedModuleLateLintPass> as rustc_hir::intravisit::Visitor>::visit_nested_item
9: rustc_lint::lint_mod
10: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::lint_mod::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>
11: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefaultCache<rustc_span::def_id::LocalModDefId, rustc_middle::query::erase::Erased<[u8; 0]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
12: rustc_query_impl::query_impl::lint_mod::get_query_non_incr::__rust_end_short_backtrace
13: rustc_lint::late::check_crate::{closure#1}
14: rustc_lint::late::check_crate
15: rustc_interface::passes::analysis
16: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 0]>>
17: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 0]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
18: rustc_query_impl::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
19: <rustc_interface::passes::create_and_enter_global_ctxt<core::option::Option<rustc_interface::queries::Linker>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2}>::{closure#2} as core::ops::function::FnOnce<(&rustc_session::session::Session, rustc_middle::ty::context::CurrentGcx, alloc::sync::Arc<rustc_data_structures::jobserver::Proxy>, &std::sync::once_lock::OnceLock<rustc_middle::ty::context::GlobalCtxt>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_middle::arena::Arena>, &rustc_data_structures::sync::worker_local::WorkerLocal<rustc_hir::Arena>, rustc_driver_impl::run_compiler::{closure#0}::{closure#2})>>::call_once::{shim:vtable#0}
20: rustc_interface::interface::run_compiler::<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}
21: std::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
22: <<std::thread::Builder>::spawn_unchecked_<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
23: std::sys::thread::unix::Thread::new::thread_start
24: <unknown>
25: <unknown>
--> /tmp/icemaker_global_tempdir.tFJc9K91h3pp/rustc_testrunner_tmpdir_reporting.bcikJhNz0lr1/mvce.rs:3:16
|
3 | pub struct Foo([u8; C]);
| ^^^^^^^
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 (3d461af2a 2025-11-18) running on x86_64-unknown-linux-gnu
note: compiler flags: -Z crate-attr=feature(min_generic_const_args) -Z dump-mir-dir=dir
query stack during panic:
end of query stack
@rustbot label +F-min_generic_const_args