'rustc' panicked at 'already borrowed: BorrowMutError' #66785
Description
I was modifying some code, really had no intention of it working and was just running it to see what errors the compiler would tell me about, but the compiler panicked and asked for a bug report so here it is. The in-progress code that causes the panic is here: ggriffiniii/yup-oauth2@9079229
The contents of the panic message are here:
$ RUST_BACKTRACE=full cargo test
Compiling yup-oauth2 v3.1.1 (/usr/local/google/home/glenng/src/yup-oauth2)
thread 'rustc' panicked at 'already borrowed: BorrowMutError', src/libcore/result.rs:1165:5
stack backtrace:
0: 0x7fd0db3d7af4 - backtrace::backtrace::libunwind::trace::hda41dbcdfba36aa0
at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.37/src/backtrace/libunwind.rs:88
1: 0x7fd0db3d7af4 - backtrace::backtrace::trace_unsynchronized::h1a8d6e1f8cb3f5d4
at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.37/src/backtrace/mod.rs:66
2: 0x7fd0db3d7af4 - std::sys_common::backtrace::_print_fmt::h610c4127487e10da
at src/libstd/sys_common/backtrace.rs:76
3: 0x7fd0db3d7af4 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h0722dc552e01bd1d
at src/libstd/sys_common/backtrace.rs:60
4: 0x7fd0db41012c - core::fmt::write::h01edf6dd68a42c9c
at src/libcore/fmt/mod.rs:1030
5: 0x7fd0db3cbd17 - std::io::Write::write_fmt::hf15985f193f03c04
at src/libstd/io/mod.rs:1412
6: 0x7fd0db3dc325 - std::sys_common::backtrace::_print::hd8d5d08a1795e743
at src/libstd/sys_common/backtrace.rs:64
7: 0x7fd0db3dc325 - std::sys_common::backtrace::print::hf89a79e3921a2366
at src/libstd/sys_common/backtrace.rs:49
8: 0x7fd0db3dc325 - std::panicking::default_hook::{{closure}}::h3a8f42beb3bb8ae3
at src/libstd/panicking.rs:196
9: 0x7fd0db3dc016 - std::panicking::default_hook::h8f803b0bc31a5c37
at src/libstd/panicking.rs:210
10: 0x7fd0db913483 - rustc_driver::report_ice::he98718c53edc6d3d
11: 0x7fd0db3dcb0c - std::panicking::rust_panic_with_hook::h825f041245da8739
at src/libstd/panicking.rs:477
12: 0x7fd0db3dc5c2 - std::panicking::continue_panic_fmt::hbe0378e33481e81b
at src/libstd/panicking.rs:380
13: 0x7fd0db3dc4b6 - rust_begin_unwind
at src/libstd/panicking.rs:307
14: 0x7fd0db409aca - core::panicking::panic_fmt::h527855ce0bc891f6
at src/libcore/panicking.rs:85
15: 0x7fd0db409d07 - core::result::unwrap_failed::ha8b77e6004f0ba38
at src/libcore/result.rs:1165
16: 0x7fd0dbe900fd - rustc_typeck::check::Inherited::register_predicate::h6d6ab2aea880daf6
17: 0x7fd0dbe902dd - rustc_typeck::check::Inherited::register_predicates::h4e2bca41d54a7f92
18: 0x7fd0dbe9a7f5 - <rustc_typeck::check::FnCtxt as rustc_typeck::astconv::AstConv>::normalize_ty::h003fa83adb304603
19: 0x7fd0dbf3965d - <dyn rustc_typeck::astconv::AstConv>::ast_ty_to_ty::hb5ab16737116477a
20: 0x7fd0dbf2d011 - <dyn rustc_typeck::astconv::AstConv>::create_substs_for_ast_path::hbcf004e45578b8dd
21: 0x7fd0dbf29ebe - <dyn rustc_typeck::astconv::AstConv>::ast_path_substs_for_ty::h0fc6ccdaa4a94456
22: 0x7fd0dbf37afc - <dyn rustc_typeck::astconv::AstConv>::res_to_ty::h838cbf426757fa76
23: 0x7fd0dbf3965d - <dyn rustc_typeck::astconv::AstConv>::ast_ty_to_ty::hb5ab16737116477a
24: 0x7fd0dbea050c - rustc_typeck::check::FnCtxt::check_argument_types::h648ecc2af68d79cc
25: 0x7fd0dbe8b042 - rustc_typeck::check::callee::<impl rustc_typeck::check::FnCtxt>::confirm_builtin_call::ha7eae76e9c28b73b
26: 0x7fd0dbe89561 - rustc_typeck::check::callee::<impl rustc_typeck::check::FnCtxt>::check_call::h45d30abc30b22158
27: 0x7fd0dbe6fcd8 - rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind::h8b25c6ef69e01f12
28: 0x7fd0dbe6f28b - rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs::h0000f1a19a63396f
29: 0x7fd0dbea39d8 - rustc_typeck::check::FnCtxt::check_block_with_expected::h0bf314ef8ed232a6
30: 0x7fd0dbe6fcf3 - rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind::h8b25c6ef69e01f12
31: 0x7fd0dbe6f28b - rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs::h0000f1a19a63396f
32: 0x7fd0dbe78d9b - rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_return_expr::h51bf174a038068dd
33: 0x7fd0dbe91e3d - rustc_typeck::check::check_fn::hb04722ffaefc34ec
34: 0x7fd0dc00a518 - rustc::ty::context::GlobalCtxt::enter_local::hee87012a37ec7481
35: 0x7fd0dbe90ea2 - rustc_typeck::check::typeck_tables_of::h7e98a74ad7491971
36: 0x7fd0dbee24ca - rustc::ty::query::__query_compute::typeck_tables_of::h8235d6e55b8e3584
37: 0x7fd0dbf7c15b - rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors for rustc::ty::query::queries::typeck_tables_of>::compute::hef02a238f3e43402
38: 0x7fd0dbf20cc2 - rustc::dep_graph::graph::DepGraph::with_task_impl::hd911b0f10264fdeb
39: 0x7fd0dbffb551 - rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query::hfde020d3574d1a10
40: 0x7fd0dbf78eaf - rustc::ty::<impl rustc::ty::context::TyCtxt>::par_body_owners::h449b282b3524b717
41: 0x7fd0dbe9091d - rustc_typeck::check::typeck_item_bodies::h0ba4bbf6daf77150
42: 0x7fd0dbee2915 - rustc::ty::query::__query_compute::typeck_item_bodies::hd123b7ff5213001d
43: 0x7fd0dbf1cbf4 - rustc::dep_graph::graph::DepGraph::with_task_impl::hb629a3b21ebb2a85
44: 0x7fd0dbfc1bed - rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query::h9919cbc7cbdee737
45: 0x7fd0dbee750e - rustc::util::common::time::h08d6b8e4f10491a9
46: 0x7fd0dc0b759f - rustc_typeck::check_crate::h2e77f97476aecad8
47: 0x7fd0db9c200a - rustc_interface::passes::analysis::h7d37d49a7360493d
48: 0x7fd0db8d5c01 - rustc::ty::query::__query_compute::analysis::h1c5cc76ea5bb496b
49: 0x7fd0db8be322 - rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query::hcf7bc9d073dcb36b
50: 0x7fd0db8dd42a - rustc_interface::passes::BoxedGlobalCtxt::access::{{closure}}::h7fc0f9f179325408
51: 0x7fd0dba3e1da - rustc_interface::passes::create_global_ctxt::{{closure}}::h10595b15ffb5db35
52: 0x7fd0db8df64e - rustc_interface::interface::run_compiler_in_existing_thread_pool::ha009ae4607895a11
53: 0x7fd0db915362 - std::thread::local::LocalKey<T>::with::h30eaff0b6e71bc49
54: 0x7fd0db91a3ce - scoped_tls::ScopedKey<T>::set::h6ab0051cc42102a7
55: 0x7fd0db93b1a2 - syntax::with_globals::h9994c1c3242d3263
56: 0x7fd0db8a7e10 - std::sys_common::backtrace::__rust_begin_short_backtrace::h229c554686840b66
57: 0x7fd0db3ed25a - __rust_maybe_catch_panic
at src/libpanic_unwind/lib.rs:80
58: 0x7fd0db8d1879 - core::ops::function::FnOnce::call_once{{vtable.shim}}::hf2e117c529f2753f
59: 0x7fd0db3be1ff - <alloc::boxed::Box<F> as core::ops::function::FnOnce<A>>::call_once::h483711add4ba2330
at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/liballoc/boxed.rs:922
60: 0x7fd0db3ebf00 - <alloc::boxed::Box<F> as core::ops::function::FnOnce<A>>::call_once::h7605b45eb29ed0be
at /rustc/4560ea788cb760f0a34127156c78e2552949f734/src/liballoc/boxed.rs:922
61: 0x7fd0db3ebf00 - std::sys_common::thread::start_thread::h557b0c2dc4449562
at src/libstd/sys_common/thread.rs:13
62: 0x7fd0db3ebf00 - std::sys::unix::thread::Thread::new::thread_start::h7c2a7f9b68fe4bba
at src/libstd/sys/unix/thread.rs:79
63: 0x7fd0db158c73 - start_thread
64: 0x7fd0daa7edef - clone
65: 0x0 - <unknown>
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 1.39.0 (4560ea788 2019-11-04) running on x86_64-unknown-linux-gnu
note: compiler flags: -C debuginfo=2 -C incremental
note: some of the compiler flags provided by cargo are hidden
query stack during panic:
#0 [typeck_tables_of] processing `authenticator::tests::ensure_send_sync`
#1 [typeck_item_bodies] type-checking all item bodies
#2 [analysis] running analysis passes on this crate
end of query stack
error: could not compile `yup-oauth2`.
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