ICE: `typeof called on const argument's anon const before the const argument was lowered`

[matthiaskrgr]

Code

//@compile-flags: -Zthreads=2
fn foo<const N: usize>() {}

fn main() {
    foo::<{
        || {};
        0
    }>();
}

Meta

rustc --version --verbose:

rustc 1.89.0-nightly (5d707b07e 2025-06-02)
binary: rustc
commit-hash: 5d707b07e42766c080c5012869c9988a18dcbb83
commit-date: 2025-06-02
host: x86_64-unknown-linux-gnu
release: 1.89.0-nightly
LLVM version: 20.1.5

Error output

<output>

Backtrace

warning: unused closure that must be used
 --> /home/matthias/vcs/github/glacier2_fuzz/fixed/137179.rs:6:9
  |
6 |         || {};
  |         ^^^^^
  |
  = note: closures are lazy and do nothing unless called
  = note: `#[warn(unused_must_use)]` 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: `type_of` called on const argument's anon const before the const argument was lowered
 --> /home/matthias/vcs/github/glacier2_fuzz/fixed/137179.rs:5:15
  |
5 |       sym foo::<{
  |  _______________^
6 | |         || {};
7 | |         0
8 | |     }>,
  | |_____^
  |
note: delayed at compiler/rustc_hir_analysis/src/collect/type_of.rs:108:14
         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::type_of::type_of
         5: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::type_of::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::type_of::get_query_non_incr::__rust_end_short_backtrace
         8: rustc_hir_typeck::typeck_with_inspect::{closure#0}
         9: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
        10: 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; 8]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
        11: rustc_query_impl::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
        12: rustc_hir_typeck::typeck_with_inspect::{closure#0}
        13: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
        14: 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; 8]>, rustc_query_system::dep_graph::graph::DepNodeIndex>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
        15: rustc_query_impl::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
        16: <rustc_middle::ty::context::TyCtxt>::par_hir_body_owners::<rustc_hir_analysis::check_crate::{closure#1}>::{closure#0}
        17: rustc_data_structures::sync::parallel::par_slice::par_rec::<&rustc_span::def_id::LocalDefId, rustc_data_structures::sync::parallel::par_for_each_in<&rustc_span::def_id::LocalDefId, &[rustc_span::def_id::LocalDefId], <rustc_middle::ty::context::TyCtxt>::par_hir_body_owners<rustc_hir_analysis::check_crate::{closure#1}>::{closure#0}>::{closure#0}::{closure#0}>
        18: rayon_core::join::join_context::<rayon_core::join::join::call<(), rustc_data_structures::sync::parallel::par_slice::par_rec<&rustc_span::def_id::LocalDefId, rustc_data_structures::sync::parallel::par_for_each_in<&rustc_span::def_id::LocalDefId, &[rustc_span::def_id::LocalDefId], <rustc_middle::ty::context::TyCtxt>::par_hir_body_owners<rustc_hir_analysis::check_crate::{closure#1}>::{closure#0}>::{closure#0}::{closure#0}>::{closure#1}>::{closure#0}, rayon_core::join::join::call<(), rustc_data_structures::sync::parallel::par_slice::par_rec<&rustc_span::def_id::LocalDefId, rustc_data_structures::sync::parallel::par_for_each_in<&rustc_span::def_id::LocalDefId, &[rustc_span::def_id::LocalDefId], <rustc_middle::ty::context::TyCtxt>::par_hir_body_owners<rustc_hir_analysis::check_crate::{closure#1}>::{closure#0}>::{closure#0}::{closure#0}>::{closure#2}>::{closure#0}, (), ()>::{closure#0}
        19: rustc_data_structures::sync::parallel::par_slice::par_rec::<&rustc_span::def_id::LocalDefId, rustc_data_structures::sync::parallel::par_for_each_in<&rustc_span::def_id::LocalDefId, &[rustc_span::def_id::LocalDefId], <rustc_middle::ty::context::TyCtxt>::par_hir_body_owners<rustc_hir_analysis::check_crate::{closure#1}>::{closure#0}>::{closure#0}::{closure#0}>
        20: <rayon_core::job::StackJob<rayon_core::latch::SpinLatch, rayon_core::join::join_context::call_b<(), rayon_core::join::join::call<(), rustc_data_structures::sync::parallel::par_slice::par_rec<&rustc_span::def_id::LocalDefId, rustc_data_structures::sync::parallel::par_for_each_in<&rustc_span::def_id::LocalDefId, &[rustc_span::def_id::LocalDefId], <rustc_middle::ty::context::TyCtxt>::par_hir_body_owners<rustc_hir_analysis::check_crate::{closure#1}>::{closure#0}>::{closure#0}::{closure#0}>::{closure#2}>::{closure#0}>::{closure#0}, ()> as rayon_core::job::Job>::execute
        21: <rayon_core::registry::WorkerThread>::wait_until_cold
        22: <rayon_core::registry::ThreadBuilder>::run
        23: std::sys::backtrace::__rust_begin_short_backtrace::<<rayon_core::ThreadPoolBuilder>::build_scoped<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#5}::{closure#0}::{closure#0}, rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#5}::{closure#0}::{closure#1}, ()>::{closure#0}::{closure#0}::{closure#0}, ()>
        24: <<std::thread::Builder>::spawn_unchecked_<<rayon_core::ThreadPoolBuilder>::build_scoped<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#5}::{closure#0}::{closure#0}, rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<(), rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#5}::{closure#0}::{closure#1}, ()>::{closure#0}::{closure#0}::{closure#0}, ()>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
        25: std::sys::pal::unix::thread::Thread::new::thread_start
        26: <unknown>
        27: <unknown>
 --> /home/matthias/vcs/github/glacier2_fuzz/fixed/137179.rs:5:15
  |
5 |       sym foo::<{
  |  _______________^
6 | |         || {};
7 | |         0
8 | |     }>,
  | |_____^

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 `/home/matthias/vcs/github/glacier2_fuzz/fixed/rustc-ice-2025-06-03T08_23_38-137028.txt` to your bug report

note: compiler flags: -Z threads=20 --crate-type lib

query stack during panic:
end of query stack

[matthiaskrgr]

bisects to #135186 🤔

[cyrgani]

//@compile-flags: -Zthreads=2
fn foo<const N: usize>() {}

fn main() {
    foo::<{
        || {};
        0
    }>();
}