ICE: impl trait in bindings can't type-check body of DefId

[DutchGhost]

Code

#![feature(impl_trait_in_bindings)]

struct Bug {
    V1: [(); {
        let f: impl core::future::Future<Output = u8> = async { 1 };
        1
    }],
}

fn main() {}

Meta

rustc --version --verbose:

rustc 1.49.0-nightly (338f939a8 2020-11-02)

Error output

error: internal compiler error: compiler/rustc_typeck/src/check/mod.rs:489:9: can't type-check body of DefId(0:3 ~ playground[f69e]::Bug)

Backtrace

thread 'rustc' panicked at 'Box<Any>', /rustc/338f939a8d77061896cd0a1ca87a2c6d1f4ec359/compiler/rustc_errors/src/lib.rs:904:9
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_typeck::check::typeck_with_fallback::{{closure}}
   9: rustc_typeck::check::typeck
  10: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::typeck>::compute
  11: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  12: rustc_data_structures::stack::ensure_sufficient_stack
  13: rustc_query_system::query::plumbing::get_query_impl
  14: rustc_typeck::collect::type_of::type_of
  15: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::type_of>::compute
  16: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  17: rustc_data_structures::stack::ensure_sufficient_stack
  18: rustc_query_system::query::plumbing::get_query_impl
  19: <rustc_trait_selection::traits::query::normalize::QueryNormalizer as rustc_middle::ty::fold::TypeFolder>::fold_ty
  20: <rustc_infer::infer::at::At as rustc_trait_selection::traits::query::normalize::AtExt>::normalize
  21: rustc_infer::infer::InferCtxtBuilder::enter
  22: rustc_traits::normalize_erasing_regions::normalize_generic_arg_after_erasing_regions
  23: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  24: rustc_data_structures::stack::ensure_sufficient_stack
  25: rustc_query_system::query::plumbing::get_query_impl
  26: <rustc_middle::ty::normalize_erasing_regions::NormalizeAfterErasingRegionsFolder as rustc_middle::ty::fold::TypeFolder>::fold_ty
  27: rustc_middle::ty::util::<impl rustc_middle::ty::TyS>::needs_drop
  28: rustc_mir::dataflow::drop_flag_effects::on_all_children_bits::on_all_children_bits
  29: <rustc_mir::transform::elaborate_drops::ElaborateDrops as rustc_mir::transform::MirPass>::run_pass
  30: rustc_mir::transform::run_passes
  31: rustc_mir::transform::run_post_borrowck_cleanup_passes
  32: rustc_mir::transform::mir_drops_elaborated_and_const_checked
  33: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::mir_drops_elaborated_and_const_checked>::compute
  34: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  35: rustc_data_structures::stack::ensure_sufficient_stack
  36: rustc_query_system::query::plumbing::get_query_impl
  37: rustc_mir::transform::optimized_mir
  38: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::optimized_mir>::compute
  39: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  40: rustc_data_structures::stack::ensure_sufficient_stack
  41: rustc_query_system::query::plumbing::get_query_impl
  42: rustc_mir::interpret::eval_context::InterpCx<M>::load_mir
  43: rustc_mir::const_eval::eval_queries::eval_to_allocation_raw_provider
  44: 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
  45: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  46: rustc_data_structures::stack::ensure_sufficient_stack
  47: rustc_query_system::query::plumbing::get_query_impl
  48: rustc_mir::const_eval::eval_queries::eval_to_const_value_raw_provider
  49: 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
  50: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  51: rustc_data_structures::stack::ensure_sufficient_stack
  52: rustc_query_system::query::plumbing::get_query_impl
  53: rustc_mir::const_eval::eval_queries::eval_to_const_value_raw_provider
  54: 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
  55: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  56: rustc_data_structures::stack::ensure_sufficient_stack
  57: rustc_query_system::query::plumbing::get_query_impl
  58: rustc_middle::mir::interpret::queries::<impl rustc_middle::ty::context::TyCtxt>::const_eval_global_id
  59: rustc_middle::mir::interpret::queries::<impl rustc_middle::ty::context::TyCtxt>::const_eval_resolve
  60: rustc_middle::ty::consts::Const::eval
  61: rustc_middle::ty::structural_impls::<impl rustc_middle::ty::fold::TypeFoldable for &rustc_middle::ty::TyS>::super_fold_with
  62: <rustc_trait_selection::traits::project::AssocTypeNormalizer as rustc_middle::ty::fold::TypeFolder>::fold_ty
  63: rustc_data_structures::stack::ensure_sufficient_stack
  64: rustc_trait_selection::traits::project::normalize
  65: <rustc_infer::infer::InferCtxt as rustc_trait_selection::infer::InferCtxtExt>::partially_normalize_associated_types_in
  66: rustc_typeck::check::inherited::Inherited::normalize_associated_types_in
  67: <core::iter::adapters::Map<I,F> as core::iter::traits::iterator::Iterator>::fold
  68: rustc_infer::infer::InferCtxtBuilder::enter
  69: rustc_typeck::check::wfcheck::check_item_well_formed
  70: 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
  71: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  72: rustc_data_structures::stack::ensure_sufficient_stack
  73: rustc_query_system::query::plumbing::get_query_impl
  74: rustc_query_system::query::plumbing::ensure_query_impl
  75: rustc_data_structures::sync::par_for_each_in
  76: rustc_hir::hir::Crate::par_visit_all_item_likes
  77: rustc_session::session::Session::track_errors
  78: rustc_typeck::check_crate
  79: rustc_interface::passes::analysis
  80: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::analysis>::compute
  81: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  82: rustc_data_structures::stack::ensure_sufficient_stack
  83: rustc_query_system::query::plumbing::get_query_impl
  84: rustc_interface::passes::QueryContext::enter
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 1.49.0-nightly (338f939a8 2020-11-02) running on x86_64-unknown-linux-gnu

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

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

query stack during panic:
#0 [typeck] type-checking `Bug`
#1 [type_of] computing type of `Bug::V1::{constant#0}::{opaque#0}`
#2 [normalize_generic_arg_after_erasing_regions] normalizing `impl std::future::Future`
#3 [mir_drops_elaborated_and_const_checked] elaborating drops for `Bug::V1::{constant#0}`
#4 [optimized_mir] optimizing MIR for `Bug::V1::{constant#0}`
#5 [eval_to_allocation_raw] const-evaluating + checking `Bug::V1::{constant#0}`
#6 [eval_to_const_value_raw] simplifying constant for the type system `Bug::V1::{constant#0}`
#7 [eval_to_const_value_raw] simplifying constant for the type system `Bug::V1::{constant#0}`
#8 [check_item_well_formed] checking that `Bug` is well-formed
#9 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 3 previous errors; 1 warning emitted

For more information about this error, try `rustc --explain E0493`.
error: could not compile `playground`

[Alexendoo]

No longer ICEs since #78809