ICE on nightly: thread 'rustc' panicked at 'called Option::unwrap() on a None value', compiler/rustc_middle/src/ty/query/mod.rs:235:5

[PaulGrandperrin]

Just like #79779 which I reported a few hours ago, it is a spurious bug, running cargo clean and then cargo run clears the ICE.
However, it doesn't really look like this bug is related to the one I just reported before.
It also comes from a different crate I'm working on.

Code

This is some WIP/playground code, please don't judge :-)

use tracing::{info, Level};
use tracing_subscriber::FmtSubscriber;

use rustyline::error::ReadlineError;
use rustyline::Editor;

fn setup_logger() {
    let subscriber = FmtSubscriber::builder()
    .with_max_level(Level::TRACE)
    .finish();

    tracing::subscriber::set_global_default(subscriber)
        .expect("setting default subscriber failed");
}

fn main() {
    setup_logger();

    let mut session = client_core::Session::new();
    let f = session.signup_test("hey");
    //futures::executor::block_on(f);

    let rt = tokio::runtime::Runtime::new().unwrap();
    rt.block_on(f);
    
    
    // `()` can be used when no completer is required
    let mut rl = Editor::<()>::new();
    if rl.load_history("history.txt").is_err() {
        println!("No previous history.");
    }
    loop {
        let readline = rl.readline(">> ");
        match readline {
            Ok(line) => {
                rl.add_history_entry(line.as_str());
                match line.split_ascii_whitespace().collect::<Vec<_>>().as_slice() {
                    ["signup", password] => {
                        session.signup(password);
                    }
                    _ => {
                        tracing::error!("unknown command");
                    }
                }
            },
            Err(ReadlineError::Interrupted) => {
                println!("CTRL-C");
                break
            },
            Err(ReadlineError::Eof) => {
                println!("CTRL-D");
                break
            },
            Err(err) => {
                println!("Error: {:?}", err);
                break
            }
        }
    }
    rl.save_history("history.txt").unwrap();
}

Meta

rustc --version --verbose:

rustc 1.50.0-nightly (0f6f2d681 2020-12-06)
binary: rustc
commit-hash: 0f6f2d681b39c5f95459cd09cb936b6ceb27cd82
commit-date: 2020-12-06
host: x86_64-unknown-linux-gnu
release: 1.50.0-nightly

Error output

   Compiling client-cli v0.1.0 (/home/paulg/Repositories/cachou-playground/client-cli)
     Running `rustc --crate-name client_cli --edition=2018 src/main.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type bin --emit=dep-info,link -C embed-bitcode=no -C debuginfo=2 -C metadata=a2808c23c7b12571 -C extra-filename=-a2808c23c7b12571 --out-dir /home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps -C incremental=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/incremental -L dependency=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps --extern client_core=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/libclient_core-6a28514683622551.rlib --extern futures=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/libfutures-43b72e0c8a3ce88c.rlib --extern rustyline=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/librustyline-43ac40a9101c84c2.rlib --extern tokio=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/libtokio-245ea55611ce700e.rlib --extern tracing=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/libtracing-231e273397d7a4f0.rlib --extern tracing_subscriber=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/libtracing_subscriber-abf5619db598f6a0.rlib -L 'native=/home/linuxbrew/.linuxbrew/Cellar/[email protected]/1.1.1h/lib'`
warning: unused import: `info`
 --> src/main.rs:1:15
  |
1 | use tracing::{info, Level};
  |               ^^^^
  |
  = note: `#[warn(unused_imports)]` on by default

thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', compiler/rustc_middle/src/ty/query/mod.rs:235:5
stack backtrace:
   0:     0x7f5abbf3f6a7 - std::backtrace_rs::backtrace::libunwind::trace::h746c3e9529d524bc
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/../../backtrace/src/backtrace/libunwind.rs:90:5
   1:     0x7f5abbf3f6a7 - std::backtrace_rs::backtrace::trace_unsynchronized::h86340908ff889faa
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f5abbf3f6a7 - std::sys_common::backtrace::_print_fmt::h43f85f9b18230404
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/sys_common/backtrace.rs:67:5
   3:     0x7f5abbf3f6a7 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hc132ae1a5b5aa7cd
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/sys_common/backtrace.rs:46:22
   4:     0x7f5abbfb351c - core::fmt::write::hdf023a0036d2a25f
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/core/src/fmt/mod.rs:1078:17
   5:     0x7f5abbf31692 - std::io::Write::write_fmt::h8580846154bcb66a
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/io/mod.rs:1519:15
   6:     0x7f5abbf433a5 - std::sys_common::backtrace::_print::h7ee55fed88d107a3
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/sys_common/backtrace.rs:49:5
   7:     0x7f5abbf433a5 - std::sys_common::backtrace::print::h54a7d3e52a524177
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/sys_common/backtrace.rs:36:9
   8:     0x7f5abbf433a5 - std::panicking::default_hook::{{closure}}::h60921e857bf55a40
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/panicking.rs:208:50
   9:     0x7f5abbf42efa - std::panicking::default_hook::hf0f9afb1017317fc
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/panicking.rs:225:9
  10:     0x7f5abc83a868 - rustc_driver::report_ice::hff78d76a39ffbb86
  11:     0x7f5abbf43ca6 - std::panicking::rust_panic_with_hook::h8d66bf42b407aaea
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/panicking.rs:595:17
  12:     0x7f5abbf43797 - std::panicking::begin_panic_handler::{{closure}}::hde71edcd925d0c5e
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/panicking.rs:495:13
  13:     0x7f5abbf3fb6c - std::sys_common::backtrace::__rust_end_short_backtrace::h8a3c7d6cea578919
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/sys_common/backtrace.rs:141:18
  14:     0x7f5abbf43729 - rust_begin_unwind
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/panicking.rs:493:5
  15:     0x7f5abbfaf931 - core::panicking::panic_fmt::h20225113c4a2f8fd
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/core/src/panicking.rs:92:14
  16:     0x7f5abbfaf87d - core::panicking::panic::h35b77276aa4b0c12
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/core/src/panicking.rs:50:5
  17:     0x7f5abf219b05 - rustc_middle::ty::query::try_load_from_on_disk_cache::hfa4775df5c5e0180
  18:     0x7f5abe4f469a - rustc_query_system::dep_graph::graph::DepGraph<K>::exec_cache_promotions::h8caa69177622351e
  19:     0x7f5abe50cef1 - rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps::hab5675af7737b3e6
  20:     0x7f5abe4b068b - rustc_incremental::persist::save::save_in::h7f4f43356280dc0a
  21:     0x7f5abe4ab4a1 - rustc_data_structures::sync::join::h0120008f852881ce
  22:     0x7f5abe50bf92 - rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps::h2893ce60eec57bb6
  23:     0x7f5abe4afbbf - rustc_incremental::persist::save::save_dep_graph::hffd3fb2ecc639a78
  24:     0x7f5abe38b07a - rustc_codegen_ssa::base::finalize_tcx::h68106e2729498b3e
  25:     0x7f5abcca9257 - <rustc_codegen_llvm::LlvmCodegenBackend as rustc_codegen_ssa::traits::backend::CodegenBackend>::codegen_crate::h067fffb3870bc5b0
  26:     0x7f5abca5892e - rustc_session::utils::<impl rustc_session::session::Session>::time::had158f21ec5bf4d1
  27:     0x7f5abca9b62c - rustc_interface::passes::QueryContext::enter::h40067ad7feabcbd0
  28:     0x7f5abcaf3a93 - rustc_interface::queries::Queries::ongoing_codegen::h4fc36fc05972247d
  29:     0x7f5abc7e34e2 - rustc_interface::queries::<impl rustc_interface::interface::Compiler>::enter::hd899306a06575d0c
  30:     0x7f5abc8765f7 - rustc_span::with_source_map::ha4e07ff263d0dc1d
  31:     0x7f5abc7e468b - rustc_interface::interface::create_compiler_and_run::h1d6d732867d1f489
  32:     0x7f5abc890b60 - scoped_tls::ScopedKey<T>::set::h39c0aa543118d3f3
  33:     0x7f5abc897346 - std::sys_common::backtrace::__rust_begin_short_backtrace::h1e5aa72fb9cd6d86
  34:     0x7f5abc7ec07a - core::ops::function::FnOnce::call_once{{vtable.shim}}::hc793837e985b77ce
  35:     0x7f5abbf5365a - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hea1090dbdcecbf5a
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/alloc/src/boxed.rs:1328:9
  36:     0x7f5abbf5365a - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h8d5723d3912bd325
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/alloc/src/boxed.rs:1328:9
  37:     0x7f5abbf5365a - std::sys::unix::thread::Thread::new::thread_start::hc17a425ca2995724
                               at /rustc/0f6f2d681b39c5f95459cd09cb936b6ceb27cd82/library/std/src/sys/unix/thread.rs:71:17
  38:     0x7f5abbe8bead - start_thread
  39:     0x7f5abbdabd2f - __clone
  40:                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/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: rustc 1.50.0-nightly (0f6f2d681 2020-12-06) running on x86_64-unknown-linux-gnu

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

query stack during panic:
end of query stack
warning: 1 warning emitted

error: could not compile `client-cli`

Caused by:
  process didn't exit successfully: `rustc --crate-name client_cli --edition=2018 src/main.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type bin --emit=dep-info,link -C embed-bitcode=no -C debuginfo=2 -C metadata=a2808c23c7b12571 -C extra-filename=-a2808c23c7b12571 --out-dir /home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps -C incremental=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/incremental -L dependency=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps --extern client_core=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/libclient_core-6a28514683622551.rlib --extern futures=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/libfutures-43b72e0c8a3ce88c.rlib --extern rustyline=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/librustyline-43ac40a9101c84c2.rlib --extern tokio=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/libtokio-245ea55611ce700e.rlib --extern tracing=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/libtracing-231e273397d7a4f0.rlib --extern tracing_subscriber=/home/paulg/Repositories/cachou-playground/client-cli/target/debug/deps/libtracing_subscriber-abf5619db598f6a0.rlib -L 'native=/home/linuxbrew/.linuxbrew/Cellar/[email protected]/1.1.1h/lib'` (exit code: 101)

[jonas-schievink]

duplicate of #79661