thread 'rustc' panicked at 'called Option::unwrap() on a None value', compiler/rustc_middle/src/hir/mod.rs:79:55

[Badel2]

I'm seeing an internal compiler error on the following input, found by fuzz-rustc:

Code

#![u=||{static d=||1;}]

Error output

error: unexpected token: `||
    {
        static d: _ = || 1;
    }`
 --> src/lib.rs:1:6
  |
1 | #![u=||{static d=||1;}]
  |      ^^^^^^^^^^^^^^^^^

error: cannot find attribute `u` in this scope
 --> src/lib.rs:1:4
  |
1 | #![u=||{static d=||1;}]
  |    ^

thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', compiler/rustc_middle/src/hir/mod.rs:79:55
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

The ICE happens after correctly reporting a few other errors, because the code is nonsense, so low priority. Affected versions: I tried nightly 2021-11-12 and stable 1.56.1 and they both show the same ICE.

Backtrace

   Compiling playground v0.0.1 (/playground)
error: unexpected token: `||
    {
        static d: _ = || 1;
    }`
 --> src/lib.rs:1:6
  |
1 | #![u=||{static d=||1;}]
  |      ^^^^^^^^^^^^^^^^^

error: cannot find attribute `u` in this scope
 --> src/lib.rs:1:4
  |
1 | #![u=||{static d=||1;}]
  |    ^

thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', compiler/rustc_middle/src/hir/mod.rs:79:55
stack backtrace:
   0: rust_begin_unwind
             at /rustc/e90c5fbbc5df5c81267747daeb937d4e955ce6ad/library/std/src/panicking.rs:498:5
   1: core::panicking::panic_fmt
             at /rustc/e90c5fbbc5df5c81267747daeb937d4e955ce6ad/library/core/src/panicking.rs:106:14
   2: core::panicking::panic
             at /rustc/e90c5fbbc5df5c81267747daeb937d4e955ce6ad/library/core/src/panicking.rs:47:5
   3: <rustc_middle::hir::provide::{closure#4} as core::ops::function::FnOnce<(rustc_middle::ty::context::TyCtxt, rustc_span::def_id::LocalDefId)>>::call_once
   4: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::plumbing::QueryCtxt, rustc_query_system::query::caches::DefaultCache<rustc_span::def_id::LocalDefId, rustc_hir::hir_id::HirId>>
   5: <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::hir_owner_parent
   6: <rustc_middle::ty::context::TyCtxt>::lint_level_at_node
   7: <rustc_typeck::check::fn_ctxt::FnCtxt>::analyze_closure
   8: rustc_hir::intravisit::walk_body::<rustc_typeck::check::upvar::InferBorrowKindVisitor>
   9: <rustc_typeck::check::fn_ctxt::FnCtxt>::closure_analyze
  10: <rustc_infer::infer::InferCtxtBuilder>::enter::<&rustc_middle::ty::context::TypeckResults, <rustc_typeck::check::inherited::InheritedBuilder>::enter<rustc_typeck::check::typeck_with_fallback<rustc_typeck::check::diagnostic_only_typeck::{closure#0}>::{closure#1}, &rustc_middle::ty::context::TypeckResults>::{closure#0}>
  11: <rustc_typeck::check::inherited::InheritedBuilder>::enter::<rustc_typeck::check::typeck_with_fallback<rustc_typeck::check::diagnostic_only_typeck::{closure#0}>::{closure#1}, &rustc_middle::ty::context::TypeckResults>
  12: rustc_typeck::check::diagnostic_only_typeck
  13: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::plumbing::QueryCtxt, rustc_query_system::query::caches::DefaultCache<rustc_span::def_id::LocalDefId, &rustc_middle::ty::context::TypeckResults>>
  14: rustc_query_system::query::plumbing::get_query::<rustc_query_impl::queries::diagnostic_only_typeck, rustc_query_impl::plumbing::QueryCtxt>
  15: rustc_typeck::collect::type_of::infer_placeholder_type
  16: rustc_typeck::collect::type_of::type_of
  17: <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::type_of
  18: <rustc_infer::infer::InferCtxtBuilder>::enter::<(), <rustc_typeck::check::inherited::InheritedBuilder>::enter<<rustc_typeck::check::wfcheck::CheckWfFcxBuilder>::with_fcx<rustc_typeck::check::wfcheck::check_item_type::{closure#0}>::{closure#0}, ()>::{closure#0}>
  19: rustc_typeck::check::wfcheck::check_item_type
  20: rustc_typeck::check::wfcheck::check_item_well_formed
  21: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::plumbing::QueryCtxt, rustc_query_system::query::caches::DefaultCache<rustc_span::def_id::LocalDefId, ()>>
  22: <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::check_item_well_formed
  23: rustc_data_structures::sync::par_for_each_in::<&alloc::vec::Vec<core::option::Option<rustc_hir::hir::OwnerInfo>>, <rustc_middle::hir::map::Map>::par_visit_all_item_likes<rustc_typeck::check::wfcheck::CheckTypeWellFormedVisitor>::{closure#0}>
  24: <rustc_session::session::Session>::track_errors::<rustc_typeck::check_crate::{closure#5}, ()>
  25: rustc_typeck::check_crate
  26: rustc_interface::passes::analysis
  27: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::plumbing::QueryCtxt, rustc_query_system::query::caches::DefaultCache<(), core::result::Result<(), rustc_errors::ErrorReported>>>
  28: rustc_query_system::query::plumbing::get_query::<rustc_query_impl::queries::analysis, rustc_query_impl::plumbing::QueryCtxt>
  29: <rustc_interface::passes::QueryContext>::enter::<rustc_driver::run_compiler::{closure#1}::{closure#2}::{closure#3}, core::result::Result<(), rustc_errors::ErrorReported>>
  30: <rustc_interface::interface::Compiler>::enter::<rustc_driver::run_compiler::{closure#1}::{closure#2}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_errors::ErrorReported>>
  31: rustc_span::with_source_map::<core::result::Result<(), rustc_errors::ErrorReported>, rustc_interface::interface::create_compiler_and_run<core::result::Result<(), rustc_errors::ErrorReported>, rustc_driver::run_compiler::{closure#1}>::{closure#1}>
  32: rustc_interface::interface::create_compiler_and_run::<core::result::Result<(), rustc_errors::ErrorReported>, rustc_driver::run_compiler::{closure#1}>
  33: <scoped_tls::ScopedKey<rustc_span::SessionGlobals>>::set::<rustc_interface::util::setup_callbacks_and_run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_errors::ErrorReported>, rustc_driver::run_compiler::{closure#1}>::{closure#0}, core::result::Result<(), rustc_errors::ErrorReported>>::{closure#0}::{closure#0}, core::result::Result<(), rustc_errors::ErrorReported>>
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

error: internal compiler error: unexpected panic

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 1.58.0-nightly (e90c5fbbc 2021-11-12) 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

query stack during panic:
#0 [hir_owner_parent] HIR parent of `{closure#0}::d`
#1 [diagnostic_only_typeck] type-checking `{closure#0}::d`
#2 [type_of] computing type of `{closure#0}::d`
#3 [check_item_well_formed] checking that `{closure#0}::d` is well-formed
#4 [analysis] running analysis passes on this crate
end of query stack
error: missing type for `static` item
 --> src/lib.rs:1:16
  |
1 | #![u=||{static d=||1;}]
  |                ^ help: provide a type for the item: `d: <type>`

error: could not compile `playground` due to 3 previous errors

Also note how there is one additional error below the backtrace, not sure if that's expected.

[michaelwoerister]

Thanks for the bug report, @Badel2!

@cjgillot, could this be related to the recent HIR map/lowering refactorings?

[Badel2]

This issue looks very similar to #81886, but the examples from there don't panic anymore.