ICE: assertion failure with -Zunpretty=mir-cfg

[matthiaskrgr]

Code

code from glacier fixed/79666.rs

#![feature(const_generics)]
#![feature(generic_associated_types)]

trait A {
    type B<const N: usize>;

    fn foo<const N: usize>(&self) -> Self::B<{N}>;
}

fn main() {}

Meta

rustc --version --verbose:

rustc 1.52.0-nightly (9b471a3f5 2021-02-19)
binary: rustc
commit-hash: 9b471a3f5fe57e5c6e08acf665f2094422415a3d
commit-date: 2021-02-19
host: x86_64-unknown-linux-gnu
release: 1.52.0-nightly
LLVM version: 11.0.1

Error output

rustc ./79666.rs -Zunpretty=mir-cfg

warning: the feature `const_generics` is incomplete and may not be safe to use and/or cause compiler crashes
 --> ./79666.rs:1:12
  |
1 | #![feature(const_generics)]
  |            ^^^^^^^^^^^^^^
  |
  = note: `#[warn(incomplete_features)]` on by default
  = note: see issue #44580 <https://github.com/rust-lang/rust/issues/44580> for more information

warning: the feature `generic_associated_types` is incomplete and may not be safe to use and/or cause compiler crashes
 --> ./79666.rs:2:12
  |
2 | #![feature(generic_associated_types)]
  |            ^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: see issue #44265 <https://github.com/rust-lang/rust/issues/44265> for more information

thread 'rustc' panicked at 'assertion failed: `(left == right)`
  left: `Some((DefId(0:8 ~ 79666[317d]::A::foo::{constant#0}), DefId(0:5 ~ 79666[317d]::A::B::N)))`,
 right: `None`', compiler/rustc_mir/src/transform/mod.rs:560:5
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/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: rustc 1.52.0-nightly (9b471a3f5 2021-02-19) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z unpretty=mir-cfg

query stack during panic:
#0 [optimized_mir] optimizing MIR for `A::foo::{constant#0}`
end of query stack
warning: 2 warnings emitted

Backtrace

warning: the feature `const_generics` is incomplete and may not be safe to use and/or cause compiler crashes
 --> ./79666.rs:1:12
  |
1 | #![feature(const_generics)]
  |            ^^^^^^^^^^^^^^
  |
  = note: `#[warn(incomplete_features)]` on by default
  = note: see issue #44580 <https://github.com/rust-lang/rust/issues/44580> for more information

warning: the feature `generic_associated_types` is incomplete and may not be safe to use and/or cause compiler crashes
 --> ./79666.rs:2:12
  |
2 | #![feature(generic_associated_types)]
  |            ^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: see issue #44265 <https://github.com/rust-lang/rust/issues/44265> for more information

thread 'rustc' panicked at 'assertion failed: `(left == right)`
  left: `Some((DefId(0:8 ~ 79666[317d]::A::foo::{constant#0}), DefId(0:5 ~ 79666[317d]::A::B::N)))`,
 right: `None`', compiler/rustc_mir/src/transform/mod.rs:560:5
stack backtrace:
   0:     0x7f1178f35ab0 - std::backtrace_rs::backtrace::libunwind::trace::hb4de9797f80b7b8c
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/../../backtrace/src/backtrace/libunwind.rs:90:5
   1:     0x7f1178f35ab0 - std::backtrace_rs::backtrace::trace_unsynchronized::h59566d0bd20efff7
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f1178f35ab0 - std::sys_common::backtrace::_print_fmt::hcfa5ce6be50275d4
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/sys_common/backtrace.rs:67:5
   3:     0x7f1178f35ab0 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hd8c307a38b9bab04
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/sys_common/backtrace.rs:46:22
   4:     0x7f1178fa6e6c - core::fmt::write::h3868db8542c90941
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/core/src/fmt/mod.rs:1092:17
   5:     0x7f1178f28992 - std::io::Write::write_fmt::hab90295d5a0f197d
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/io/mod.rs:1568:15
   6:     0x7f1178f399a5 - std::sys_common::backtrace::_print::h19224910b8700cf1
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/sys_common/backtrace.rs:49:5
   7:     0x7f1178f399a5 - std::sys_common::backtrace::print::h25dedfa68c5fb84a
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/sys_common/backtrace.rs:36:9
   8:     0x7f1178f399a5 - std::panicking::default_hook::{{closure}}::h12c5765653a72a42
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/panicking.rs:208:50
   9:     0x7f1178f39453 - std::panicking::default_hook::he65cee71c4209f0c
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/panicking.rs:225:9
  10:     0x7f117979808b - rustc_driver::report_ice::h56d5f6e6a9fb9d03
  11:     0x7f1178f3a2a6 - std::panicking::rust_panic_with_hook::h01a674d863fe0d8a
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/panicking.rs:595:17
  12:     0x7f1178f39dc7 - std::panicking::begin_panic_handler::{{closure}}::h9b9fecf185178864
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/panicking.rs:497:13
  13:     0x7f1178f35f4c - std::sys_common::backtrace::__rust_end_short_backtrace::h57be46a42dc7f24b
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/sys_common/backtrace.rs:141:18
  14:     0x7f1178f39d29 - rust_begin_unwind
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/panicking.rs:493:5
  15:     0x7f1178fa3491 - core::panicking::panic_fmt::h20225113c4a2f8fd
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/core/src/panicking.rs:92:14
  16:     0x7f117c15bf05 - rustc_mir::transform::optimized_mir::h245976003198d078
  17:     0x7f117975d5a3 - rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::optimized_mir>::compute::h962929d1c2186a42
  18:     0x7f1179790754 - rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl::h987bcc4d742b6eab
  19:     0x7f11797919ec - rustc_query_system::dep_graph::graph::DepGraph<K>::with_task::h640404db930a6fbb
  20:     0x7f11797b5274 - rustc_data_structures::stack::ensure_sufficient_stack::hd389d807f70b11da
  21:     0x7f117975fa55 - rustc_query_system::query::plumbing::force_query_with_job::h4d36fcda7c0d6736
  22:     0x7f117975f060 - rustc_query_system::query::plumbing::get_query_impl::hff20e28a826798af
  23:     0x7f1179761ab1 - rustc_query_system::query::plumbing::get_query::h5f686cd74df0b95e
  24:     0x7f11797aa9a2 - rustc_mir::util::graphviz::write_mir_graphviz::he12cbf8a95c30fe6
  25:     0x7f117974d5e4 - rustc_driver::pretty::print_after_hir_lowering::h102b65afa3784540
  26:     0x7f117979f63e - rustc_interface::passes::QueryContext::enter::he206c0d61f6fb2e9
  27:     0x7f117bb0a6d7 - rustc_interface::queries::<impl rustc_interface::interface::Compiler>::enter::hae97633c8f5175d4
  28:     0x7f117bb02e11 - rustc_span::with_source_map::hd16d211d24c668a9
  29:     0x7f117bb09c62 - scoped_tls::ScopedKey<T>::set::h08e96579ac07fec5
  30:     0x7f117bb0b448 - std::sys_common::backtrace::__rust_begin_short_backtrace::h84dc4b3263d56f8c
  31:     0x7f117bae9aba - core::ops::function::FnOnce::call_once{{vtable.shim}}::h209d27a00dc0b7e3
  32:     0x7f1178f4affa - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h321523073ee11258
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/alloc/src/boxed.rs:1546:9
  33:     0x7f1178f4affa - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hf0e85e12c83b99b3
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/alloc/src/boxed.rs:1546:9
  34:     0x7f1178f4affa - std::sys::unix::thread::Thread::new::thread_start::hba22c7961aa0e2f8
                               at /rustc/9b471a3f5fe57e5c6e08acf665f2094422415a3d/library/std/src/sys/unix/thread.rs:71:17
  35:     0x7f1178e50299 - start_thread
  36:     0x7f1178d65153 - clone
  37:                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 1.52.0-nightly (9b471a3f5 2021-02-19) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z unpretty=mir-cfg

query stack during panic:
#0 [optimized_mir] optimizing MIR for `A::foo::{constant#0}`
end of query stack
warning: 2 warnings emitted

[matthiaskrgr]

@rustbot modify labels: requires-nightly