ice: Normalizing Alias(Weak, .. without wrapping it in a Binder

[matthiaskrgr]

auto-reduced (treereduce-rust):

type Foo<'a, 'b> = (i32, impl PartialEq);

fn main<'a, 'main>(i: &'a i32) -> Foo<'a, 'b> {}

original:

#![feature(type_alias_impl_trait)]

type Bar<'b, 'b> = impl PartialEq<Bar<'b, 'b>> + std::fmt::Debug;

fn bar<'a, 'b>(i: &'muh i32) -> PartialEq<Foo<'a, 'b>> {
    //~^ ERROR can't compare `&i32` with `Bar<'b, 'a>`
    i
}

type Foo<'a, 'b> = (i32, impl PartialEq<Moo<'b, 'a>> + std::fmt::Debug);

fn main<'a, 'main>(i: &'a i32) -> Foo<'a, 'b> {
    let meh = 42;
    let muh = 69;
    assert_eq!(bar(&meh), bar(&meh));
}

type Moo<'a, 'b> = (i32, impl PartialEq<Moo<'b, 'a>> + std::fmt::Debug);

fn moo<'a, 'a>(i: &'a i32) -> Moo<'a, 'a> {
    //~^ ERROR can't compare `&i32` with `(i32, Moo<'b, 'a>::{opaque#0})`
    (42, i)
}

fn main() {
    let muh = 69;
    let muh = 69;
    assert_eq!(bar(&meh), bar(&meh));
}

Version information

rustc 1.77.0-nightly (767453eb7 2023-12-21)
binary: rustc
commit-hash: 767453eb7ca188e991ac5568c17b984dd4893e77
commit-date: 2023-12-21
host: x86_64-unknown-linux-gnu
release: 1.77.0-nightly
LLVM version: 17.0.6

Command:
/home/matthias/.rustup/toolchains/master/bin/rustc

Program output

error[E0261]: use of undeclared lifetime name `'b`
 --> /tmp/icemaker_global_tempdir.B42R90mmNE5j/rustc_testrunner_tmpdir_reporting.YzkVDJKC7PfJ/mvce.rs:3:43
  |
3 | fn main<'a, 'main>(i: &'a i32) -> Foo<'a, 'b> {}
  |         -                                 ^^ undeclared lifetime
  |         |
  |         help: consider introducing lifetime `'b` here: `'b,`

error[E0658]: `impl Trait` in type aliases is unstable
 --> /tmp/icemaker_global_tempdir.B42R90mmNE5j/rustc_testrunner_tmpdir_reporting.YzkVDJKC7PfJ/mvce.rs:1:26
  |
1 | type Foo<'a, 'b> = (i32, impl PartialEq);
  |                          ^^^^^^^^^^^^^^
  |
  = 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

error[E0308]: mismatched types
 --> /tmp/icemaker_global_tempdir.B42R90mmNE5j/rustc_testrunner_tmpdir_reporting.YzkVDJKC7PfJ/mvce.rs:3:35
  |
3 | fn main<'a, 'main>(i: &'a i32) -> Foo<'a, 'b> {}
  |    ----                           ^^^^^^^^^^^ expected `(i32, _)`, found `()`
  |    |
  |    implicitly returns `()` as its body has no tail or `return` expression
  |
  = note:  expected tuple `(i32, _)`
          found unit type `()`

thread 'rustc' panicked at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/compiler/rustc_trait_selection/src/traits/project.rs:486:9:
Normalizing Alias(Weak, AliasTy { args: [ReBound(DebruijnIndex(0), BoundRegion { var: 0, kind: BrNamed(DefId(0:7 ~ mvce[4ba3]::main::'a), 'a) }), ReError], def_id: DefId(0:3 ~ mvce[4ba3]::Foo) }) without wrapping in a `Binder`
stack backtrace:
   0:     0x7f1eaf38b6f6 - std::backtrace_rs::backtrace::libunwind::trace::hcd45df0585a5632e
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5
   1:     0x7f1eaf38b6f6 - std::backtrace_rs::backtrace::trace_unsynchronized::h195da99cf8e2fd54
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f1eaf38b6f6 - std::sys_common::backtrace::_print_fmt::h262e79324a83e225
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/sys_common/backtrace.rs:68:5
   3:     0x7f1eaf38b6f6 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h3898f35ef0ca54d5
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7f1eaf3ddf40 - core::fmt::rt::Argument::fmt::h8d1b33c649461322
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/core/src/fmt/rt.rs:142:9
   5:     0x7f1eaf3ddf40 - core::fmt::write::ha50192d3a32248da
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/core/src/fmt/mod.rs:1120:17
   6:     0x7f1eaf37f53f - std::io::Write::write_fmt::h8abf221f3aa8e5cd
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/io/mod.rs:1810:15
   7:     0x7f1eaf38b4d4 - std::sys_common::backtrace::_print::haf5efe20c2739270
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7f1eaf38b4d4 - std::sys_common::backtrace::print::h0a4325d21f82186c
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7f1eaf38e267 - std::panicking::default_hook::{{closure}}::h0dd1d67390b9ca78
  10:     0x7f1eaf38dfc9 - std::panicking::default_hook::h695297bcdcf25d64
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/panicking.rs:292:9
  11:     0x7f1eb21a1e7b - std[3d4a347d4b60aa5c]::panicking::update_hook::<alloc[ff74c2bc34e84412]::boxed::Box<rustc_driver_impl[825d30c548056d90]::install_ice_hook::{closure#0}>>::{closure#0}
  12:     0x7f1eaf38e9b6 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h71dc5e7c88edc0fd
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/alloc/src/boxed.rs:2029:9
  13:     0x7f1eaf38e9b6 - std::panicking::rust_panic_with_hook::hae536ee97f103a54
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/panicking.rs:783:13
  14:     0x7f1eaf38e702 - std::panicking::begin_panic_handler::{{closure}}::h2788c2493b3e7f9e
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/panicking.rs:657:13
  15:     0x7f1eaf38bbf6 - std::sys_common::backtrace::__rust_end_short_backtrace::hfc5e328ccb4034f4
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/sys_common/backtrace.rs:171:18
  16:     0x7f1eaf38e460 - rust_begin_unwind
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/panicking.rs:645:5
  17:     0x7f1eaf3da645 - core::panicking::panic_fmt::h3e853967d7f83fbf
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/core/src/panicking.rs:72:14
  18:     0x7f1eb3870e39 - <rustc_trait_selection[9cf4c997531174d8]::traits::engine::ObligationCtxt>::normalize::<rustc_middle[d7fe0914d11d0412]::ty::Ty>
  19:     0x7f1eb40b4d85 - rustc_hir_analysis[4c9d02161d6f28f2]::check::check::check_mod_item_types
  20:     0x7f1eb40b3447 - rustc_query_impl[4ab443e5c52f63d]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[4ab443e5c52f63d]::query_impl::check_mod_item_types::dynamic_query::{closure#2}::{closure#0}, rustc_middle[d7fe0914d11d0412]::query::erase::Erased<[u8; 0usize]>>
  21:     0x7f1eb40bc6fb - rustc_query_system[1af031bf8266f50f]::query::plumbing::try_execute_query::<rustc_query_impl[4ab443e5c52f63d]::DynamicConfig<rustc_query_system[1af031bf8266f50f]::query::caches::DefaultCache<rustc_span[fa10d2db69bc2c22]::def_id::LocalModDefId, rustc_middle[d7fe0914d11d0412]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[4ab443e5c52f63d]::plumbing::QueryCtxt, false>
  22:     0x7f1eb40bc0d7 - rustc_query_impl[4ab443e5c52f63d]::query_impl::check_mod_item_types::get_query_non_incr::__rust_end_short_backtrace
  23:     0x7f1eb3d43593 - rustc_hir_analysis[4c9d02161d6f28f2]::check_crate
  24:     0x7f1eb3abc2e0 - rustc_interface[f8b5fde174ad67]::passes::analysis
  25:     0x7f1eb3abbf1d - rustc_query_impl[4ab443e5c52f63d]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[4ab443e5c52f63d]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[d7fe0914d11d0412]::query::erase::Erased<[u8; 1usize]>>
  26:     0x7f1eb43c5032 - rustc_query_system[1af031bf8266f50f]::query::plumbing::try_execute_query::<rustc_query_impl[4ab443e5c52f63d]::DynamicConfig<rustc_query_system[1af031bf8266f50f]::query::caches::SingleCache<rustc_middle[d7fe0914d11d0412]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[4ab443e5c52f63d]::plumbing::QueryCtxt, false>
  27:     0x7f1eb43c4e39 - rustc_query_impl[4ab443e5c52f63d]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  28:     0x7f1eb444fc52 - rustc_interface[f8b5fde174ad67]::interface::run_compiler::<core[3d376420add8b96f]::result::Result<(), rustc_span[fa10d2db69bc2c22]::ErrorGuaranteed>, rustc_driver_impl[825d30c548056d90]::run_compiler::{closure#0}>::{closure#0}
  29:     0x7f1eb43e2086 - std[3d4a347d4b60aa5c]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[f8b5fde174ad67]::util::run_in_thread_with_globals<rustc_interface[f8b5fde174ad67]::util::run_in_thread_pool_with_globals<rustc_interface[f8b5fde174ad67]::interface::run_compiler<core[3d376420add8b96f]::result::Result<(), rustc_span[fa10d2db69bc2c22]::ErrorGuaranteed>, rustc_driver_impl[825d30c548056d90]::run_compiler::{closure#0}>::{closure#0}, core[3d376420add8b96f]::result::Result<(), rustc_span[fa10d2db69bc2c22]::ErrorGuaranteed>>::{closure#0}, core[3d376420add8b96f]::result::Result<(), rustc_span[fa10d2db69bc2c22]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[3d376420add8b96f]::result::Result<(), rustc_span[fa10d2db69bc2c22]::ErrorGuaranteed>>
  30:     0x7f1eb43e1eb3 - <<std[3d4a347d4b60aa5c]::thread::Builder>::spawn_unchecked_<rustc_interface[f8b5fde174ad67]::util::run_in_thread_with_globals<rustc_interface[f8b5fde174ad67]::util::run_in_thread_pool_with_globals<rustc_interface[f8b5fde174ad67]::interface::run_compiler<core[3d376420add8b96f]::result::Result<(), rustc_span[fa10d2db69bc2c22]::ErrorGuaranteed>, rustc_driver_impl[825d30c548056d90]::run_compiler::{closure#0}>::{closure#0}, core[3d376420add8b96f]::result::Result<(), rustc_span[fa10d2db69bc2c22]::ErrorGuaranteed>>::{closure#0}, core[3d376420add8b96f]::result::Result<(), rustc_span[fa10d2db69bc2c22]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[3d376420add8b96f]::result::Result<(), rustc_span[fa10d2db69bc2c22]::ErrorGuaranteed>>::{closure#1} as core[3d376420add8b96f]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  31:     0x7f1eaf3988e5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h08e9f3a633db8c74
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/alloc/src/boxed.rs:2015:9
  32:     0x7f1eaf3988e5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h852c72dc884e3d23
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/alloc/src/boxed.rs:2015:9
  33:     0x7f1eaf3988e5 - std::sys::unix::thread::Thread::new::thread_start::h43781093432e8beb
                               at /rustc/767453eb7ca188e991ac5568c17b984dd4893e77/library/std/src/sys/unix/thread.rs:108:17
  34:     0x7f1eaf1849eb - <unknown>
  35:     0x7f1eaf2087cc - <unknown>
  36:                0x0 - <unknown>

error: 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 1.77.0-nightly (767453eb7 2023-12-21) running on x86_64-unknown-linux-gnu

query stack during panic:
#0 [check_mod_item_types] checking item types in top-level module
#1 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 3 previous errors

Some errors have detailed explanations: E0261, E0308, E0658.
For more information about an error, try `rustc --explain E0261`.

[matthiaskrgr]

Regression in #119047 ping @mu001999