Internal compiler error with labeled break inside closure

[Undin]

Toolchain version: rustc 1.38.0-nightly (dfd52ba 2019-07-06)

The following code produces internal compiler error

#![feature(label_break_value)]

fn main() {
    let a = 'a: {
        let a = |x: i32| break 'a;
        1
    };
}

backtrace

thread 'rustc' panicked at 'Box<Any>', src/librustc_errors/lib.rs:649:9
stack backtrace:
error: internal compiler error: src/librustc_typeck/check/mod.rs:509: could not find enclosing breakable with id HirId { owner: DefIndex(12), local_id: 9 }

thread 'rustc' panicked at 'Box<Any>', src/librustc_errors/lib.rs:649:9
stack backtrace:
   0: std::panicking::default_hook::{{closure}}
   0: std::panicking::default_hook::{{closure}}
   1: std::panicking::default_hook
   1: std::panicking::default_hook
   2: rustc::util::common::panic_hook
   2: rustc::util::common::panic_hook
   3: std::panicking::rust_panic_with_hook
   3: std::panicking::rust_panic_with_hook
   4: std::panicking::begin_panic
   4: std::panicking::begin_panic
   5: rustc_errors::Handler::bug
   5: rustc_errors::Handler::bug
   6: rustc::util::bug::opt_span_bug_fmt::{{closure}}
   6: rustc::util::bug::opt_span_bug_fmt::{{closure}}
   7: rustc::ty::context::tls::with_opt::{{closure}}
   7: rustc::ty::context::tls::with_opt::{{closure}}
   8: rustc::ty::context::tls::with_context_opt
   8: rustc::ty::context::tls::with_context_opt
   9: rustc::ty::context::tls::with_opt
   9: rustc::ty::context::tls::with_opt
  10: rustc::util::bug::opt_span_bug_fmt
  10: rustc::util::bug::opt_span_bug_fmt
  11: rustc::util::bug::bug_fmt
  11: rustc::util::bug::bug_fmt
  12: rustc_typeck::check::EnclosingBreakables::find_breakable::{{closure}}
  12: rustc_typeck::check::EnclosingBreakables::find_breakable::{{closure}}
  13: rustc_typeck::check::EnclosingBreakables::find_breakable
  13: rustc_typeck::check::EnclosingBreakables::find_breakable
  14: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  14: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  15: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_return_expr
  16: rustc_typeck::check::check_fn
  15: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_return_expr
  16: rustc_typeck::check::check_fn
  17: rustc_typeck::check::closure::<impl rustc_typeck::check::FnCtxt>::check_expr_closure
  17: rustc_typeck::check::closure::<impl rustc_typeck::check::FnCtxt>::check_expr_closure
  18: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  18: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  19: rustc_typeck::check::FnCtxt::check_decl_initializer
  19: rustc_typeck::check::FnCtxt::check_decl_initializer
  20: rustc_typeck::check::FnCtxt::check_decl_local
  21: rustc_typeck::check::FnCtxt::check_stmt
  20: rustc_typeck::check::FnCtxt::check_decl_local
  22: rustc_typeck::check::FnCtxt::check_block_with_expected
  21: rustc_typeck::check::FnCtxt::check_stmt
  22: rustc_typeck::check::FnCtxt::check_block_with_expected
  23: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  23: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  24: rustc_typeck::check::FnCtxt::check_decl_initializer
  24: rustc_typeck::check::FnCtxt::check_decl_initializer
  25: rustc_typeck::check::FnCtxt::check_decl_local
  25: rustc_typeck::check::FnCtxt::check_decl_local
  26: rustc_typeck::check::FnCtxt::check_stmt
  26: rustc_typeck::check::FnCtxt::check_stmt
  27: rustc_typeck::check::FnCtxt::check_block_with_expected
  27: rustc_typeck::check::FnCtxt::check_block_with_expected
  28: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  28: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  29: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_return_expr
  29: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_return_expr
  30: rustc_typeck::check::check_fn
  30: rustc_typeck::check::check_fn
  31: rustc::ty::context::GlobalCtxt::enter_local
  31: rustc::ty::context::GlobalCtxt::enter_local
  32: rustc_typeck::check::typeck_tables_of
  32: rustc_typeck::check::typeck_tables_of
  33: rustc::ty::query::__query_compute::typeck_tables_of
  33: rustc::ty::query::__query_compute::typeck_tables_of
  34: rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors for rustc::ty::query::queries::typeck_tables_of>::compute
  34: rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors for rustc::ty::query::queries::typeck_tables_of>::compute
  35: rustc::dep_graph::graph::DepGraph::with_task_impl
  35: rustc::dep_graph::graph::DepGraph::with_task_impl
  36: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  36: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  37: rustc::ty::<impl rustc::ty::context::TyCtxt>::par_body_owners
  37: rustc::ty::<impl rustc::ty::context::TyCtxt>::par_body_owners
  38: rustc_typeck::check::typeck_item_bodies
  38: rustc_typeck::check::typeck_item_bodies
  39: rustc::ty::query::__query_compute::typeck_item_bodies
  39: rustc::ty::query::__query_compute::typeck_item_bodies
  40: rustc::dep_graph::graph::DepGraph::with_task_impl
  40: rustc::dep_graph::graph::DepGraph::with_task_impl
  41: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  41: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  42: rustc::util::common::time
  42: rustc::util::common::time
  43: rustc_typeck::check_crate
  43: rustc_typeck::check_crate
  44: rustc_interface::passes::analysis
  44: rustc_interface::passes::analysis
  45: rustc::ty::query::__query_compute::analysis
  45: rustc::ty::query::__query_compute::analysis
  46: rustc::dep_graph::graph::DepGraph::with_task_impl
  46: rustc::dep_graph::graph::DepGraph::with_task_impl
  47: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  47: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  48: rustc_interface::passes::BoxedGlobalCtxt::access::{{closure}}
  48: rustc_interface::passes::BoxedGlobalCtxt::access::{{closure}}
  49: rustc_interface::passes::create_global_ctxt::{{closure}}
  49: rustc_interface::passes::create_global_ctxt::{{closure}}
  50: rustc_interface::interface::run_compiler_in_existing_thread_pool
  50: rustc_interface::interface::run_compiler_in_existing_thread_pool
  51: std::thread::local::LocalKey<T>::with
  51: std::thread::local::LocalKey<T>::with
  52: scoped_tls::ScopedKey<T>::set
  53: syntax::with_globals
  52: scoped_tls::ScopedKey<T>::set
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
  53: syntax::with_globals
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
query stack during panic:
query stack during panic:
#0 [typeck_tables_of] processing `main`
#0 [typeck_tables_of] processing `main`
#1 [typeck_item_bodies] type-checking all item bodies
#2 [analysis] running analysis passes on this crate
end of query stack
#1 [typeck_item_bodies] type-checking all item bodies
#2 [analysis] running analysis passes on this crate
end of query stack

[Patryk27]

Simplified, FWIW:

#![feature(label_break_value)]

fn main() {
    'a: {
        || break 'a
    }
}

[jonas-schievink]

Another instance: #63837

(the feature gate isn't needed to trigger this)

[JohnTitor]

The original example is no longer ICE but the minified example is still ICE on the latest master (on my local). We should re-open this or file it as a new issue? CC: @estebank