ICE: src/librustc_middle/ty/subst.rs:568:17: const parameter N/#0 (Const { ty: usize, val: Param(N/#0) }/0) out of range when substituting substs=[]

[eopb]

Code

fn foo<const N: usize>() -> [(); N + 1] {
    unimplemented!()
}

https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=a2ca1d2ba3c49f2540baebfb8ac167a0

Similar to #75913 this ICE goes away when adding #![feature(const_generics)].

Meta

Same error on beta and nightly.

rustc --version --verbose:

rustc 1.46.0 (04488afe3 2020-08-24)
binary: rustc
commit-hash: 04488afe34512aa4c33566eb16d8c912a3ae04f9
commit-date: 2020-08-24
host: x86_64-unknown-linux-gnu
release: 1.46.0
LLVM version: 10.0

Error output

error[E0658]: const generics are unstable
 --> src/lib.rs:1:14
  |
1 | fn foo<const N: usize>() -> [(); N + 1] {
  |              ^
  |
  = note: see issue #74878 <https://github.com/rust-lang/rust/issues/74878> for more information
  = help: add `#![feature(min_const_generics)]` to the crate attributes to enable

error: internal compiler error: compiler/rustc_middle/src/ty/subst.rs:568:17: const parameter `N/#0` (Const { ty: usize, val: Param(N/#0) }/0) out of range when substituting substs=[]

thread 'rustc' panicked at 'Box<Any>', /rustc/c71248b70870960af9993de4f31d3cba9bbce7e8/compiler/rustc_errors/src/lib.rs:891:9
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

note: 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: rustc 1.49.0-nightly (c71248b70 2020-10-11) running on x86_64-unknown-linux-gnu

note: compiler flags: -C embed-bitcode=no -C codegen-units=1 -C debuginfo=2 --crate-type lib

note: some of the compiler flags provided by cargo are hidden

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0658`.
error: could not compile `playground`

To learn more, run the command again with --verbose.

Backtrace

❯ RUST_BACKTRACE=1 rustc next2.rs                                                     Mon 12 Oct 2020 10:44:30 BST
error[E0658]: const generics are unstable
 --> next2.rs:1:14
  |
1 | fn foo<const N: usize>() -> [(); N + 1] {
  |              ^
  |
  = note: see issue #74878 <https://github.com/rust-lang/rust/issues/74878> for more information
  = help: add `#![feature(min_const_generics)]` to the crate attributes to enable

error[E0601]: `main` function not found in crate `next2`
 --> next2.rs:1:1
  |
1 | / fn foo<const N: usize>() -> [(); N + 1] {
2 | |     unimplemented!()
3 | | }
  | |_^ consider adding a `main` function to `next2.rs`

error: internal compiler error: compiler/rustc_middle/src/ty/subst.rs:568:17: const parameter `N/#0` (Const { ty: usize, val: Param(N/#0) }/0) out of range when substituting substs=[]

thread 'rustc' panicked at 'Box<Any>', /rustc/8b4085359ae798dedb05c95ad42520557bd25320/compiler/rustc_errors/src/lib.rs:891:9
stack backtrace:
   0: std::panicking::begin_panic
   1: rustc_errors::HandlerInner::span_bug
   2: rustc_errors::Handler::span_bug
   3: rustc_middle::util::bug::opt_span_bug_fmt::{{closure}}
   4: rustc_middle::ty::context::tls::with_opt::{{closure}}
   5: rustc_middle::ty::context::tls::with_opt
   6: rustc_middle::util::bug::opt_span_bug_fmt
   7: rustc_middle::util::bug::span_bug_fmt
   8: <rustc_middle::ty::subst::SubstFolder as rustc_middle::ty::fold::TypeFolder>::fold_const
   9: rustc_middle::ty::normalize_erasing_regions::<impl rustc_middle::ty::context::TyCtxt>::subst_and_normalize_erasing_regions
  10: rustc_mir::interpret::operand::<impl rustc_mir::interpret::eval_context::InterpCx<M>>::eval_operand
  11: rustc_mir::interpret::step::<impl rustc_mir::interpret::eval_context::InterpCx<M>>::eval_rvalue_into_place
  12: rustc_mir::interpret::step::<impl rustc_mir::interpret::eval_context::InterpCx<M>>::run
  13: rustc_mir::const_eval::eval_queries::eval_to_allocation_raw_provider
  14: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::eval_to_allocation_raw>::compute
  15: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  16: rustc_data_structures::stack::ensure_sufficient_stack
  17: rustc_query_system::query::plumbing::get_query_impl
  18: rustc_mir::const_eval::eval_queries::eval_to_const_value_raw_provider
  19: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::eval_to_const_value_raw>::compute
  20: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  21: rustc_data_structures::stack::ensure_sufficient_stack
  22: rustc_query_system::query::plumbing::get_query_impl
  23: rustc_mir::const_eval::eval_queries::eval_to_const_value_raw_provider
  24: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::eval_to_const_value_raw>::compute
  25: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  26: rustc_data_structures::stack::ensure_sufficient_stack
  27: rustc_query_system::query::plumbing::get_query_impl
  28: rustc_middle::mir::interpret::queries::<impl rustc_middle::ty::context::TyCtxt>::const_eval_global_id
  29: rustc_middle::mir::interpret::queries::<impl rustc_middle::ty::context::TyCtxt>::const_eval_resolve
  30: <rustc_trait_selection::traits::project::AssocTypeNormalizer as rustc_middle::ty::fold::TypeFolder>::fold_const
  31: rustc_middle::ty::structural_impls::<impl rustc_middle::ty::fold::TypeFoldable for &rustc_middle::ty::TyS>::super_fold_with
  32: <rustc_trait_selection::traits::project::AssocTypeNormalizer as rustc_middle::ty::fold::TypeFolder>::fold_ty
  33: rustc_middle::ty::structural_impls::fold_list
  34: rustc_trait_selection::traits::project::AssocTypeNormalizer::fold
  35: rustc_trait_selection::traits::project::normalize
  36: <rustc_infer::infer::InferCtxt as rustc_trait_selection::infer::InferCtxtExt>::partially_normalize_associated_types_in
  37: rustc_typeck::check::inherited::Inherited::normalize_associated_types_in
  38: rustc_infer::infer::InferCtxtBuilder::enter
  39: rustc_typeck::check::wfcheck::check_item_fn
  40: rustc_typeck::check::wfcheck::check_item_well_formed
  41: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::check_item_well_formed>::compute
  42: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  43: rustc_data_structures::stack::ensure_sufficient_stack
  44: rustc_query_system::query::plumbing::get_query_impl
  45: rustc_query_system::query::plumbing::ensure_query_impl
  46: rustc_data_structures::sync::par_for_each_in
  47: rustc_hir::hir::Crate::par_visit_all_item_likes
  48: rustc_typeck::check_crate
  49: rustc_interface::passes::analysis
  50: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::analysis>::compute
  51: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  52: rustc_data_structures::stack::ensure_sufficient_stack
  53: rustc_query_system::query::plumbing::get_query_impl
  54: rustc_interface::passes::QueryContext::enter
  55: rustc_interface::queries::<impl rustc_interface::interface::Compiler>::enter
  56: rustc_span::with_source_map
  57: rustc_interface::interface::create_compiler_and_run
  58: scoped_tls::ScopedKey<T>::set
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

note: 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: rustc 1.48.0-nightly (8b4085359 2020-09-23) running on x86_64-unknown-linux-gnu

query stack during panic:
#0 [eval_to_allocation_raw] const-evaluating + checking `foo::{{constant}}#0`
#1 [eval_to_const_value_raw] simplifying constant for the type system `foo::{{constant}}#0`
#2 [eval_to_const_value_raw] simplifying constant for the type system `foo::{{constant}}#0`
#3 [check_item_well_formed] checking that `foo` is well-formed
#4 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 3 previous errors

Some errors have detailed explanations: E0601, E0658.
For more information about an error, try `rustc --explain E0601`.

[lcnr]

This one's a duplicate of #71922