StableHasher ICE in nightly-2020-05-17

[VShell]

I cannot currently create a reproducible example of this. This ICE was introduced between nightly-2020-05-16 and nightly-2020-05-17, and exists through to (current) nightly-2020-05-25.

Meta

rustc --version --verbose:

rustc 1.45.0-nightly (dd927a5b0 2020-05-16)
binary: rustc
commit-hash: dd927a5b0f29342f7ad919fb52ca29510d2e7362
commit-date: 2020-05-16
host: x86_64-unknown-linux-gnu
release: 1.45.0-nightly
LLVM version: 9.0

Error output

error: internal compiler error: src/librustc_middle/ich/impls_ty.rs:97: StableHasher: unexpected region '_#1r

thread 'rustc' panicked at 'Box<Any>', src/librustc_errors/lib.rs:907:9

note: compiler flags: -C embed-bitcode=no -C debuginfo=2 -C incremental --crate-type bin

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

Backtrace

   0: backtrace::backtrace::libunwind::trace
             at /cargo/registry/src/jackfan.us.kg-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/libunwind.rs:86
   1: backtrace::backtrace::trace_unsynchronized
             at /cargo/registry/src/jackfan.us.kg-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/mod.rs:66
   2: std::sys_common::backtrace::_print_fmt
             at src/libstd/sys_common/backtrace.rs:78
   3: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
             at src/libstd/sys_common/backtrace.rs:59
   4: core::fmt::write
             at src/libcore/fmt/mod.rs:1069
   5: std::io::Write::write_fmt
             at src/libstd/io/mod.rs:1537
   6: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:62
   7: std::sys_common::backtrace::print
             at src/libstd/sys_common/backtrace.rs:49
   8: std::panicking::default_hook::{{closure}}
             at src/libstd/panicking.rs:198
   9: std::panicking::default_hook
             at src/libstd/panicking.rs:218
  10: rustc_driver::report_ice
  11: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:481
  12: std::panicking::begin_panic
  13: rustc_errors::HandlerInner::bug
  14: rustc_errors::Handler::bug
  15: rustc_middle::util::bug::opt_span_bug_fmt::{{closure}}
  16: rustc_middle::ty::context::tls::with_opt::{{closure}}
  17: rustc_middle::ty::context::tls::with_opt
  18: rustc_middle::util::bug::opt_span_bug_fmt
  19: rustc_middle::util::bug::bug_fmt
  20: rustc_middle::ich::impls_ty::<impl rustc_data_structures::stable_hasher::HashStable<rustc_middle::ich::hcx::StableHashingContext> for rustc_middle::ty::sty::RegionKind>::hash_stable
  21: rustc_middle::ty::sty::_DERIVE_rustc_data_structures_stable_hasher_HashStable_rustc_middle_ich_StableHashingContext_ctx_FOR_TyKind::<impl rustc_data_structures::stable_hasher::HashStable<rustc_middle::ich::hcx::StableHashingContext> for rustc_middle::ty::sty::TyKind>::hash_stable
  22: rustc_query_system::dep_graph::dep_node::DepNode<K>::construct
  23: rustc_query_system::query::plumbing::get_query_impl
  24: <rustc_infer::infer::InferCtxt as rustc_trait_selection::traits::error_reporting::suggestions::InferCtxtExt>::suggest_await_before_try
  25: <rustc_infer::infer::InferCtxt as rustc_trait_selection::traits::error_reporting::InferCtxtExt>::report_selection_error
  26: <rustc_infer::infer::InferCtxt as rustc_trait_selection::traits::error_reporting::InferCtxtExt>::report_fulfillment_errors
  27: rustc_typeck::check::FnCtxt::check_argument_types
  28: rustc_typeck::check::callee::<impl rustc_typeck::check::FnCtxt>::confirm_builtin_call
  29: rustc_typeck::check::callee::<impl rustc_typeck::check::FnCtxt>::check_call
  30: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind
  31: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  32: rustc_typeck::check::_match::<impl rustc_typeck::check::FnCtxt>::check_match
  33: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind
  34: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  35: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind
  36: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  37: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind
  38: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  39: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_coercable_to_type
  40: rustc_typeck::check::FnCtxt::check_decl_local
  41: rustc_typeck::check::FnCtxt::check_stmt
  42: rustc_typeck::check::FnCtxt::check_block_with_expected
  43: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind
  44: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  45: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind
  46: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  47: rustc_typeck::check::FnCtxt::check_block_with_expected
  48: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind
  49: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  50: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_return_expr
  51: rustc_typeck::check::check_fn
  52: rustc_typeck::check::closure::<impl rustc_typeck::check::FnCtxt>::check_expr_closure
  53: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind
  54: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  55: rustc_typeck::check::FnCtxt::check_argument_types
  56: rustc_typeck::check::callee::<impl rustc_typeck::check::FnCtxt>::confirm_builtin_call
  57: rustc_typeck::check::callee::<impl rustc_typeck::check::FnCtxt>::check_call
  58: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind
  59: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  60: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_return_expr
  61: rustc_typeck::check::check_fn
  62: rustc_middle::ty::context::GlobalCtxt::enter_local
  63: rustc_typeck::check::typeck_tables_of
  64: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::typeck_tables_of>::compute
  65: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps
  66: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  67: rustc_data_structures::stack::ensure_sufficient_stack
  68: rustc_query_system::query::plumbing::get_query_impl
  69: rustc_mir_build::hair::cx::Cx::new
  70: rustc_middle::ty::context::GlobalCtxt::enter_local
  71: rustc_mir_build::build::mir_built
  72: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::mir_built>::compute
  73: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps
  74: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  75: rustc_data_structures::stack::ensure_sufficient_stack
  76: rustc_query_system::query::plumbing::get_query_impl
  77: rustc_mir::transform::check_unsafety::unsafety_check_result
  78: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::unsafety_check_result>::compute
  79: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps
  80: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  81: rustc_data_structures::stack::ensure_sufficient_stack
  82: rustc_query_system::query::plumbing::get_query_impl
  83: rustc_mir::transform::mir_const
  84: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::mir_const>::compute
  85: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps
  86: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  87: rustc_data_structures::stack::ensure_sufficient_stack
  88: rustc_query_system::query::plumbing::get_query_impl
  89: rustc_mir::transform::mir_validated
  90: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::mir_validated>::compute
  91: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps
  92: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  93: rustc_data_structures::stack::ensure_sufficient_stack
  94: rustc_query_system::query::plumbing::get_query_impl
  95: rustc_mir::borrow_check::mir_borrowck
  96: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::mir_borrowck>::compute
  97: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps
  98: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
  99: rustc_query_system::query::plumbing::get_query_impl
 100: rustc_typeck::collect::type_of::type_of
 101: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps
 102: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
 103: rustc_data_structures::stack::ensure_sufficient_stack
 104: rustc_query_system::query::plumbing::get_query_impl
 105: rustc_middle::ty::util::<impl rustc_middle::ty::context::TyCtxt>::try_expand_impl_trait_type::OpaqueTypeExpander::expand_opaque_ty

[csmoe]

Duplicate of #72442