ICE: ` unhandled type: {type error}`

[matthiaskrgr]

auto-reduced (treereduce-rust):

type Foo = impl Send;

struct A;

const VALUE: Foo = value();

fn test(foo: Foo<'a>, f: impl for<'b> FnMut()) {
    match VALUE {
        0 | 0 => {}

        _ => (),
    }
}

original:

type Foo = impl Send;

struct A;

const VALUE: Foo = value();

fn test(
        foo: Foo<'a>,
        f: impl for<'b> FnMut(Self::FooRef<'b>),
    ) {
    match VALUE {
        0 | 0 => {}

        _ => (),
    }
}

Version information

rustc 1.80.0-nightly (97bf25c8c 2024-05-16)
binary: rustc
commit-hash: 97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f
commit-date: 2024-05-16
host: x86_64-unknown-linux-gnu
release: 1.80.0-nightly
LLVM version: 18.1.4

Command:
/home/matthias/.rustup/toolchains/master/bin/rustc -Zvalidate-mir

Program output

error[E0261]: use of undeclared lifetime name `'a`
 --> /tmp/icemaker_global_tempdir.6IiXJq3YtRlA/rustc_testrunner_tmpdir_reporting.KGuZhLmwhEmD/mvce.rs:7:18
  |
7 | fn test(foo: Foo<'a>, f: impl for<'b> FnMut()) {
  |        -         ^^ undeclared lifetime
  |        |
  |        help: consider introducing lifetime `'a` here: `<'a>`

error[E0658]: `impl Trait` in type aliases is unstable
 --> /tmp/icemaker_global_tempdir.6IiXJq3YtRlA/rustc_testrunner_tmpdir_reporting.KGuZhLmwhEmD/mvce.rs:1:12
  |
1 | type Foo = impl Send;
  |            ^^^^^^^^^
  |
  = note: see issue #63063 <https://github.com/rust-lang/rust/issues/63063> for more information
  = help: add `#![feature(type_alias_impl_trait)]` to the crate attributes to enable
  = note: this compiler was built on 2024-05-16; consider upgrading it if it is out of date

error[E0601]: `main` function not found in crate `mvce`
  --> /tmp/icemaker_global_tempdir.6IiXJq3YtRlA/rustc_testrunner_tmpdir_reporting.KGuZhLmwhEmD/mvce.rs:13:2
   |
13 | }
   |  ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.6IiXJq3YtRlA/rustc_testrunner_tmpdir_reporting.KGuZhLmwhEmD/mvce.rs`

error[E0425]: cannot find function `value` in this scope
 --> /tmp/icemaker_global_tempdir.6IiXJq3YtRlA/rustc_testrunner_tmpdir_reporting.KGuZhLmwhEmD/mvce.rs:5:20
  |
5 | const VALUE: Foo = value();
  |                    ^^^^^ not found in this scope

error[E0107]: type alias takes 0 lifetime arguments but 1 lifetime argument was supplied
 --> /tmp/icemaker_global_tempdir.6IiXJq3YtRlA/rustc_testrunner_tmpdir_reporting.KGuZhLmwhEmD/mvce.rs:7:14
  |
7 | fn test(foo: Foo<'a>, f: impl for<'b> FnMut()) {
  |              ^^^---- help: remove these generics
  |              |
  |              expected 0 lifetime arguments
  |
note: type alias defined here, with 0 lifetime parameters
 --> /tmp/icemaker_global_tempdir.6IiXJq3YtRlA/rustc_testrunner_tmpdir_reporting.KGuZhLmwhEmD/mvce.rs:1:6
  |
1 | type Foo = impl Send;
  |      ^^^

warning: unreachable pattern
 --> /tmp/icemaker_global_tempdir.6IiXJq3YtRlA/rustc_testrunner_tmpdir_reporting.KGuZhLmwhEmD/mvce.rs:9:13
  |
9 |         0 | 0 => {}
  |             ^
  |
  = note: `#[warn(unreachable_patterns)]` on by default

warning: unused variable: `foo`
 --> /tmp/icemaker_global_tempdir.6IiXJq3YtRlA/rustc_testrunner_tmpdir_reporting.KGuZhLmwhEmD/mvce.rs:7:9
  |
7 | fn test(foo: Foo<'a>, f: impl for<'b> FnMut()) {
  |         ^^^ help: if this is intentional, prefix it with an underscore: `_foo`
  |
  = note: `#[warn(unused_variables)]` on by default

warning: unused variable: `f`
 --> /tmp/icemaker_global_tempdir.6IiXJq3YtRlA/rustc_testrunner_tmpdir_reporting.KGuZhLmwhEmD/mvce.rs:7:23
  |
7 | fn test(foo: Foo<'a>, f: impl for<'b> FnMut()) {
  |                       ^ help: if this is intentional, prefix it with an underscore: `_f`

error: internal compiler error: compiler/rustc_const_eval/src/transform/validate.rs:1374:30: unhandled type: {type error}

thread 'rustc' panicked at compiler/rustc_const_eval/src/transform/validate.rs:1374:30:
Box<dyn Any>
stack backtrace:
   0:     0x733ec3d339e5 - std::backtrace_rs::backtrace::libunwind::trace::h5fef6a8b33f07067
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/std/src/../../backtrace/src/backtrace/libunwind.rs:105:5
   1:     0x733ec3d339e5 - std::backtrace_rs::backtrace::trace_unsynchronized::h6b8a04457810b752
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x733ec3d339e5 - std::sys_common::backtrace::_print_fmt::h77d7d1bbbc4229b7
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/std/src/sys_common/backtrace.rs:68:5
   3:     0x733ec3d339e5 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hf20574f93e14a2f1
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x733ec3d82b9b - core::fmt::rt::Argument::fmt::h23348174c5722978
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/core/src/fmt/rt.rs:165:63
   5:     0x733ec3d82b9b - core::fmt::write::hd7cce5a4518d8fcc
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/core/src/fmt/mod.rs:1169:21
   6:     0x733ec3d286cf - std::io::Write::write_fmt::he0dc0196eacbf547
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/std/src/io/mod.rs:1835:15
   7:     0x733ec3d337be - std::sys_common::backtrace::_print::h8c8ac3edb452e461
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x733ec3d337be - std::sys_common::backtrace::print::h585b780817d313e4
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x733ec3d361b9 - std::panicking::default_hook::{{closure}}::h6f51b42428cf3ee0
  10:     0x733ec3d35efd - std::panicking::default_hook::h7c2d4035884dc1c0
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/std/src/panicking.rs:298:9
  11:     0x733ec06fd2ff - std[9df4ad2bb6f4fdc9]::panicking::update_hook::<alloc[66fd9561b21ccf21]::boxed::Box<rustc_driver_impl[aefe405b0e9c583e]::install_ice_hook::{closure#0}>>::{closure#0}
  12:     0x733ec3d368eb - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h61418e85d4bc7a4f
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/alloc/src/boxed.rs:2036:9
  13:     0x733ec3d368eb - std::panicking::rust_panic_with_hook::hf60a62c858a4a3e2
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/std/src/panicking.rs:799:13
  14:     0x733ec072d084 - std[9df4ad2bb6f4fdc9]::panicking::begin_panic::<rustc_errors[416f919b3054adbc]::ExplicitBug>::{closure#0}
  15:     0x733ec0729c86 - std[9df4ad2bb6f4fdc9]::sys_common::backtrace::__rust_end_short_backtrace::<std[9df4ad2bb6f4fdc9]::panicking::begin_panic<rustc_errors[416f919b3054adbc]::ExplicitBug>::{closure#0}, !>
  16:     0x733ec0729966 - std[9df4ad2bb6f4fdc9]::panicking::begin_panic::<rustc_errors[416f919b3054adbc]::ExplicitBug>
  17:     0x733ec0736321 - <rustc_errors[416f919b3054adbc]::diagnostic::BugAbort as rustc_errors[416f919b3054adbc]::diagnostic::EmissionGuarantee>::emit_producing_guarantee
  18:     0x733ec0bfc88c - rustc_middle[6382b0f0af84a456]::util::bug::opt_span_bug_fmt::<rustc_span[c8a197c6866abc7b]::span_encoding::Span>::{closure#0}
  19:     0x733ec0be175a - rustc_middle[6382b0f0af84a456]::ty::context::tls::with_opt::<rustc_middle[6382b0f0af84a456]::util::bug::opt_span_bug_fmt<rustc_span[c8a197c6866abc7b]::span_encoding::Span>::{closure#0}, !>::{closure#0}
  20:     0x733ec0be15fb - rustc_middle[6382b0f0af84a456]::ty::context::tls::with_context_opt::<rustc_middle[6382b0f0af84a456]::ty::context::tls::with_opt<rustc_middle[6382b0f0af84a456]::util::bug::opt_span_bug_fmt<rustc_span[c8a197c6866abc7b]::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
  21:     0x733ebeeeaef0 - rustc_middle[6382b0f0af84a456]::util::bug::bug_fmt
  22:     0x733ebf5778cd - <rustc_const_eval[ec18fc4bc70e7081]::transform::validate::TypeChecker as rustc_middle[6382b0f0af84a456]::mir::visit::Visitor>::visit_terminator
  23:     0x733ec233096c - rustc_const_eval[ec18fc4bc70e7081]::transform::validate::validate_types
  24:     0x733ebfb57e18 - <rustc_const_eval[ec18fc4bc70e7081]::transform::validate::Validator as rustc_middle[6382b0f0af84a456]::mir::MirPass>::run_pass
  25:     0x733ebfbf7100 - rustc_mir_transform[598a3370fed2ea16]::pass_manager::validate_body
  26:     0x733ec1a01c85 - rustc_mir_transform[598a3370fed2ea16]::pass_manager::run_passes_inner
  27:     0x733ec1ea4850 - rustc_mir_transform[598a3370fed2ea16]::mir_drops_elaborated_and_const_checked
  28:     0x733ec1ea407d - rustc_query_impl[f76ee426649ffec0]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[f76ee426649ffec0]::query_impl::mir_drops_elaborated_and_const_checked::dynamic_query::{closure#2}::{closure#0}, rustc_middle[6382b0f0af84a456]::query::erase::Erased<[u8; 8usize]>>
  29:     0x733ec2109bf1 - rustc_query_system[67be369387497d6c]::query::plumbing::try_execute_query::<rustc_query_impl[f76ee426649ffec0]::DynamicConfig<rustc_query_system[67be369387497d6c]::query::caches::VecCache<rustc_span[c8a197c6866abc7b]::def_id::LocalDefId, rustc_middle[6382b0f0af84a456]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[f76ee426649ffec0]::plumbing::QueryCtxt, false>
  30:     0x733ec210958c - rustc_query_impl[f76ee426649ffec0]::query_impl::mir_drops_elaborated_and_const_checked::get_query_non_incr::__rust_end_short_backtrace
  31:     0x733ec258cd88 - rustc_interface[8a51f960ec385412]::passes::analysis
  32:     0x733ec258bb5b - rustc_query_impl[f76ee426649ffec0]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[f76ee426649ffec0]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[6382b0f0af84a456]::query::erase::Erased<[u8; 1usize]>>
  33:     0x733ec27e1525 - rustc_query_system[67be369387497d6c]::query::plumbing::try_execute_query::<rustc_query_impl[f76ee426649ffec0]::DynamicConfig<rustc_query_system[67be369387497d6c]::query::caches::SingleCache<rustc_middle[6382b0f0af84a456]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[f76ee426649ffec0]::plumbing::QueryCtxt, false>
  34:     0x733ec27e1289 - rustc_query_impl[f76ee426649ffec0]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  35:     0x733ec2672c0e - rustc_interface[8a51f960ec385412]::interface::run_compiler::<core[29d7d95333d708ae]::result::Result<(), rustc_span[c8a197c6866abc7b]::ErrorGuaranteed>, rustc_driver_impl[aefe405b0e9c583e]::run_compiler::{closure#0}>::{closure#1}
  36:     0x733ec265e5c9 - std[9df4ad2bb6f4fdc9]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[8a51f960ec385412]::util::run_in_thread_with_globals<rustc_interface[8a51f960ec385412]::util::run_in_thread_pool_with_globals<rustc_interface[8a51f960ec385412]::interface::run_compiler<core[29d7d95333d708ae]::result::Result<(), rustc_span[c8a197c6866abc7b]::ErrorGuaranteed>, rustc_driver_impl[aefe405b0e9c583e]::run_compiler::{closure#0}>::{closure#1}, core[29d7d95333d708ae]::result::Result<(), rustc_span[c8a197c6866abc7b]::ErrorGuaranteed>>::{closure#0}, core[29d7d95333d708ae]::result::Result<(), rustc_span[c8a197c6866abc7b]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[29d7d95333d708ae]::result::Result<(), rustc_span[c8a197c6866abc7b]::ErrorGuaranteed>>
  37:     0x733ec265e376 - <<std[9df4ad2bb6f4fdc9]::thread::Builder>::spawn_unchecked_<rustc_interface[8a51f960ec385412]::util::run_in_thread_with_globals<rustc_interface[8a51f960ec385412]::util::run_in_thread_pool_with_globals<rustc_interface[8a51f960ec385412]::interface::run_compiler<core[29d7d95333d708ae]::result::Result<(), rustc_span[c8a197c6866abc7b]::ErrorGuaranteed>, rustc_driver_impl[aefe405b0e9c583e]::run_compiler::{closure#0}>::{closure#1}, core[29d7d95333d708ae]::result::Result<(), rustc_span[c8a197c6866abc7b]::ErrorGuaranteed>>::{closure#0}, core[29d7d95333d708ae]::result::Result<(), rustc_span[c8a197c6866abc7b]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[29d7d95333d708ae]::result::Result<(), rustc_span[c8a197c6866abc7b]::ErrorGuaranteed>>::{closure#2} as core[29d7d95333d708ae]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  38:     0x733ec3d4078b - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hf256b52a0d01de19
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/alloc/src/boxed.rs:2022:9
  39:     0x733ec3d4078b - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hae70927392e12d5f
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/alloc/src/boxed.rs:2022:9
  40:     0x733ec3d4078b - std::sys::pal::unix::thread::Thread::new::thread_start::h5749d225aca46043
                               at /rustc/97bf25c8cf6c7c97c851c6e8bc94fd0824885e6f/library/std/src/sys/pal/unix/thread.rs:108:17
  41:     0x733ebd4a955a - <unknown>
  42:     0x733ebd526a3c - <unknown>
  43:                0x0 - <unknown>

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: please make sure that you have updated to the latest nightly

note: rustc 1.80.0-nightly (97bf25c8c 2024-05-16) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z validate-mir -Z dump-mir-dir=dir

query stack during panic:
#0 [mir_drops_elaborated_and_const_checked] elaborating drops for `test`
#1 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 6 previous errors; 3 warnings emitted

Some errors have detailed explanations: E0107, E0261, E0425, E0601, E0658.
For more information about an error, try `rustc --explain E0107`.