Rustc panic: Option::unwrap() on None at src/librustc/hir/mod.rs:81:37

[ChrisGreenaway]

Code

Sorry to not provide something more precise, but this was reported to me by Travis here: https://travis-ci.com/github/ChrisGreenaway/cargo-local-registry/jobs/299634154

You can reproduce it with:

git clone https://github.com/ChrisGreenaway/cargo-local-registry.git
cd cargo-local-registry
cargo +nightly build

But it looks like the problem was caused by some code in the docopt crate.

Meta

rustc --version --verbose:

$ rustc +nightly --version --verbose
rustc 1.44.0-nightly (7ceebd98c 2020-03-17)
binary: rustc
commit-hash: 7ceebd98c6a15ae30e772eebb676b63ffa1a8122
commit-date: 2020-03-17
host: x86_64-pc-windows-msvc
release: 1.44.0-nightly
LLVM version: 9.0

Error output

thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', src\librustc\hir\mod.rs:81:37
note: run with `RUST_BACKTRACE=1` environment variable to display a 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/blob/master/CONTRIBUTING.md#bug-reports

note: rustc 1.44.0-nightly (7ceebd98c 2020-03-17) running on x86_64-pc-windows-msvc

note: compiler flags: -C debuginfo=2 --crate-type lib

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

error: could not compile `docopt`.

To learn more, run the command again with --verbose.
warning: build failed, waiting for other jobs to finish...
error: build failed

Backtrace

$ cargo +nightly build
   Compiling docopt v1.1.0
thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', src\librustc\hir\mod.rs:81:37
stack backtrace:
   0: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
   1: core::fmt::write
   2: <std::io::IoSlice as core::fmt::Debug>::fmt
   3: std::panicking::take_hook
   4: std::panicking::take_hook
   5: rustc_driver::report_ice
   6: std::panicking::rust_panic_with_hook
   7: rust_begin_unwind
   8: core::panicking::panic_fmt
   9: core::panicking::panic
  10: rustc::ty::structural_impls::<impl rustc::ty::context::Lift for rustc_span::span_encoding::Span>::lift_to_tcx
  11: rustc::ty::<impl rustc::ty::context::TyCtxt>::is_object_safe
  12: rustc::dep_graph::graph::DepGraph::assert_ignored
  13: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::try_print_query_stack
  14: rustc::hir::map::Map::find_entry
  15: rustc::hir::map::Map::find
  16: <rustc_passes::upvars::CaptureCollector as rustc_hir::intravisit::Visitor>::visit_expr
  17: <rustc_passes::weak_lang_items::Context as rustc_hir::intravisit::Visitor>::visit_foreign_item
  18: rustc_passes::dead::check_crate
  19: rustc_interface::interface::parse_cfgspecs
  20: rustc_interface::queries::Linker::link
  21: rustc_interface::passes::QueryContext::print_stats
  22: rustc_errors::snippet::MultilineAnnotation::increase_depth
  23: <alloc::vec::Vec<rustc_ast::ast::Attribute> as rustc_ast::attr::HasAttrs>::attrs
  24: <alloc::vec::Vec<rustc_ast::ast::Attribute> as rustc_ast::attr::HasAttrs>::attrs
  25: <rustc_driver::args::Error as core::fmt::Debug>::fmt
  26: <alloc::vec::Vec<rustc_ast::ast::Attribute> as rustc_ast::attr::HasAttrs>::attrs
  27: <rustc_driver::DEFAULT_HOOK as core::ops::deref::Deref>::deref
  28: <alloc::vec::Vec<rustc_ast::ast::Attribute> as rustc_ast::attr::HasAttrs>::attrs
  29: ZN244_$LT$std..error..$LT$impl$u20$core..convert..From$LT$alloc..string..String$GT$$u20$for$u20$alloc..boxed..Box$LT$dyn$u20$std..error.
.Error$u2b$core..marker..Send$u2b$core..marker..Sync$GT$$GT$..from..StringError$u20$as$u20$core..fmt..Display$GT$3fmt17
  30: std::sys::windows::thread::Thread::new
  31: BaseThreadInitThunk
  32: RtlUserThreadStart
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/blob/master/CONTRIBUTING.md#bug-reports

note: rustc 1.44.0-nightly (7ceebd98c 2020-03-17) running on x86_64-pc-windows-msvc

note: compiler flags: -C debuginfo=2 --crate-type lib

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

query stack during panic:
#0 [hir_owner] processing `regex`
#1 [analysis] running analysis passes on this crate
end of query stack
error: could not compile `docopt`.

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

[jonas-schievink]

duplicate of #70041