delayed bug: Missing value for constant, but no error reported?

[SparkyPotato]

Code

#![feature(generic_const_exprs)]

trait NodeIndex: Copy {}

struct Interface<'a, T: NodeIndex> {
    borrow: &'a (),
    _phantom: std::marker::PhantomData<fn() -> T>,
}

trait Component: 'static {
    type NodeIndex: NodeIndex;
    fn exec(&mut self, nodes: Interface<'_, Self::NodeIndex>);
}

trait SimpleComponent: 'static {
    const NODES: usize;
    fn exec(&mut self, input: [f32; Self::NODES]) -> [f32; Self::NODES];
}

#[derive(Copy, Clone)]
struct Node<const NODES: usize>(u8);
impl<const NODES: usize> NodeIndex for Node<NODES> {}

impl<T: SimpleComponent> Component for T 
where
    [(); T::NODES]:, // This where bound causes the ICE
{
    type NodeIndex = Node<{T::NODES}>;
    fn exec(&mut self, nodes: Interface<'_, Self::NodeIndex>) { /* ICEs even if the function is empty */ }
}

The above code doesn't reproduce the error, but has a similar structure to what causes the ICE in a larger codebase. Even in the codebase where it ICEs, creating a trait with the exact same definition (call it ComponentCopy), and then replacing the impl Component for T with:

- impl<T: SimpleComponent> Component for T where [(); T::NODES]: { ... }
+ impl<T: SimpleComponent> ComponentCopy for T where [(); T::NODES]: { /* same as above */ }
+ impl<T: ComponentCopy> Component for T { /* forward the assoc. type and method */ }

doesn't cause the ICE anymore.

There isn't even a span attached to the delayed error.

Meta

rustc --version --verbose:

rustc 1.82.0-nightly (28a58f2fa 2024-07-31)
binary: rustc
commit-hash: 28a58f2fa7f0c46b8fab8237c02471a915924fe5
commit-date: 2024-07-31
host: x86_64-pc-windows-msvc
release: 1.82.0-nightly
LLVM version: 19.1.0

Error output

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: Missing value for constant, but no error reported?
  |
  = note: delayed at compiler\rustc_trait_selection\src\traits\const_evaluatable.rs:74:68

Backtrace

delayed bug: Missing value for constant, but no error reported?
   0: std::backtrace_rs::backtrace::dbghelp64::trace
             at /rustc/28a58f2fa7f0c46b8fab8237c02471a915924fe5/library\std\src\..\..\backtrace\src\backtrace\dbghelp64.rs:91
   1: std::backtrace_rs::backtrace::trace_unsynchronized
             at /rustc/28a58f2fa7f0c46b8fab8237c02471a915924fe5/library\std\src\..\..\backtrace\src\backtrace\mod.rs:66
   2: std::backtrace::Backtrace::create
             at /rustc/28a58f2fa7f0c46b8fab8237c02471a915924fe5/library\std\src\backtrace.rs:331
   3: std::backtrace::Backtrace::capture
             at /rustc/28a58f2fa7f0c46b8fab8237c02471a915924fe5/library\std\src\backtrace.rs:296
   4: <rustc_errors::DiagCtxtHandle>::steal_fulfilled_expectation_ids
   5: <rustc_errors::DiagCtxtHandle>::emit_diagnostic
   6: <rustc_span::ErrorGuaranteed as rustc_errors::diagnostic::EmissionGuarantee>::emit_producing_guarantee
   7: <rustc_const_eval::errors::WriteThroughImmutablePointer as rustc_errors::diagnostic::LintDiagnostic<()>>::decorate_lint
   8: rustc_trait_selection::traits::const_evaluatable::is_const_evaluatable
   9: <rustc_trait_selection::traits::select::SelectionContext>::evaluate_root_obligation
  10: rustc_traits::evaluate_obligation::evaluate_obligation
  11: rustc_query_impl::plumbing::query_key_hash_verify_all
  12: rustc_ty_utils::ty::self_ty_of_trait_impl_enabling_order_dep_trait_object_hack
  13: rustc_query_impl::plumbing::query_key_hash_verify_all
  14: <rustc_infer::infer::InferCtxt as rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt>::evaluate_obligation_no_overflow
  15: <rustc_infer::infer::InferCtxt as rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt>::predicate_may_hold
  16: <rustc_codegen_llvm::builder::Builder as rustc_codegen_ssa::traits::builder::BuilderMethods>::load_operand
  17: rustc_hir_typeck::method::probe::method_autoderef_steps
  18: rustc_hir_typeck::method::probe::method_autoderef_steps
  19: rustc_hir_typeck::typeck
  20: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  21: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  22: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  23: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  24: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  25: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  26: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  27: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  28: rustc_hir_typeck::typeck
  29: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  30: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  31: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  32: rustc_hir_typeck::typeck
  33: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  34: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  35: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  36: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  37: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  38: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  39: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  40: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  41: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  42: <<rustc_hir_typeck::fn_ctxt::FnCtxt>::deduce_closure_signature_from_predicates::MentionsTy as rustc_type_ir::visit::TypeVisitor<rustc_middle::ty::context::TyCtxt>>::visit_ty
  43: rustc_hir_typeck::typeck
  44: rustc_hir_typeck::typeck
  45: rustc_query_impl::plumbing::query_key_hash_verify_all
  46: rustc_ty_utils::ty::self_ty_of_trait_impl_enabling_order_dep_trait_object_hack
  47: rustc_query_impl::plumbing::query_key_hash_verify_all
  48: <rustc_hir_typeck::upvar::InferBorrowKind as rustc_hir_typeck::expr_use_visitor::Delegate>::borrow
  49: rustc_hir_analysis::check_crate
  50: rustc_interface::passes::analysis
  51: <dyn std::io::Write as nu_ansi_term::write::AnyWrite>::write_str
  52: rustc_ty_utils::ty::adt_sized_constraint
  53: rustc_query_impl::query_system
  54: _wpgmptr
  55: _wpgmptr
  56: _wpgmptr
  57: alloc::boxed::impl$48::call_once
             at /rustc/28a58f2fa7f0c46b8fab8237c02471a915924fe5/library\alloc\src\boxed.rs:2148
  58: alloc::boxed::impl$48::call_once
             at /rustc/28a58f2fa7f0c46b8fab8237c02471a915924fe5/library\alloc\src\boxed.rs:2148
  59: std::sys::pal::windows::thread::impl$0::new::thread_start
             at /rustc/28a58f2fa7f0c46b8fab8237c02471a915924fe5/library\std\src\sys\pal\windows\thread.rs:55
  60: BaseThreadInitThunk
  61: RtlUserThreadStart



rustc version: 1.82.0-nightly (28a58f2fa 2024-07-31)
platform: x86_64-pc-windows-msvc

[matthiaskrgr]

probably a duplicate of #110378