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ICE: Weak and Inherent aliases should have been normalized away already #120891

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matthiaskrgr opened this issue Feb 10, 2024 · 1 comment · Fixed by #120899
Closed

ICE: Weak and Inherent aliases should have been normalized away already #120891

matthiaskrgr opened this issue Feb 10, 2024 · 1 comment · Fixed by #120899
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@compiler-errors
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C-bug Category: This is a bug. F-type_alias_impl_trait `#[feature(type_alias_impl_trait)]` I-ICE Issue: The compiler panicked, giving an Internal Compilation Error (ICE) ❄️ T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. WG-trait-system-refactor The Rustc Trait System Refactor Initiative (-Znext-solver)

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@matthiaskrgr
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auto-reduced (treereduce-rust):

trait Foo {}

type Bar<T: Foo> = impl std::fmt::Debug;

trait Bop {}

impl Bop for Bar<usize> {}

type Barr = impl std::fmt::Debug;

impl Bop for Barr {}

original:

#![feature(type_alias_impl_trait)]

trait Foo {}
impl Foo for () {}
impl Foo for i32 {}

type Bar<T: Foo> = impl std::fmt::Debug;
fn defining_use<T: Foo>() -> Bar<T> {
    42
}

trait Bop {}

impl Bop for Bar<()> {}

// If the hidden type is the same, this is effectively a second impl for the same type.
impl Bop for Bar<usize> {}
//~^ ERROR conflicting implementations

type Barr = impl std::fmt::Debug;
fn defining_use2() -> Barr {
    42
}

// Even completely different opaque types must conflict.
impl Bop for Barr {}
//~^ ERROR conflicting implementations

// And obviously the hidden type must conflict, too.
impl Bop for i32 {}
//~^ ERROR conflicting implementations

fn main() {}

Version information

rustc 1.78.0-nightly (6cc484351 2024-02-10)
binary: rustc
commit-hash: 6cc4843512d613f51ec81aba689180c31b0b28b6
commit-date: 2024-02-10
host: x86_64-unknown-linux-gnu
release: 1.78.0-nightly
LLVM version: 17.0.6

Command:
/home/matthias/.rustup/toolchains/master/bin/rustc -Znext-solver=coherence

Program output 

error[E0658]: `impl Trait` in type aliases is unstable
 --> /tmp/icemaker_global_tempdir.RM2beP5WREmU/rustc_testrunner_tmpdir_reporting.WcwnBtogFJ2R/mvce.rs:3:20
  |
3 | type Bar<T: Foo> = impl std::fmt::Debug;
  |                    ^^^^^^^^^^^^^^^^^^^^
  |
  = 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 2024-02-10; consider upgrading it if it is out of date

error[E0658]: `impl Trait` in type aliases is unstable
 --> /tmp/icemaker_global_tempdir.RM2beP5WREmU/rustc_testrunner_tmpdir_reporting.WcwnBtogFJ2R/mvce.rs:9:13
  |
9 | type Barr = impl std::fmt::Debug;
  |             ^^^^^^^^^^^^^^^^^^^^
  |
  = 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 2024-02-10; consider upgrading it if it is out of date

error[E0601]: `main` function not found in crate `mvce`
  --> /tmp/icemaker_global_tempdir.RM2beP5WREmU/rustc_testrunner_tmpdir_reporting.WcwnBtogFJ2R/mvce.rs:11:21
   |
11 | impl Bop for Barr {}
   |                     ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.RM2beP5WREmU/rustc_testrunner_tmpdir_reporting.WcwnBtogFJ2R/mvce.rs`

thread 'rustc' panicked at compiler/rustc_trait_selection/src/solve/assembly/mod.rs:615:17:
internal error: entered unreachable code: Weak and Inherent aliases should have been normalized away already
stack backtrace:
   0:     0x7f6dd758b936 - std::backtrace_rs::backtrace::libunwind::trace::hce337a0fd0c5e1da
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5
   1:     0x7f6dd758b936 - std::backtrace_rs::backtrace::trace_unsynchronized::hbc9b4a5cec9b81eb
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f6dd758b936 - std::sys_common::backtrace::_print_fmt::habe453adcd959f3b
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/sys_common/backtrace.rs:68:5
   3:     0x7f6dd758b936 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h67bb2d10ecb8af10
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7f6dd75de380 - core::fmt::rt::Argument::fmt::hd5debad710e176b4
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/core/src/fmt/rt.rs:142:9
   5:     0x7f6dd75de380 - core::fmt::write::h5987d5bee25e3bd6
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/core/src/fmt/mod.rs:1120:17
   6:     0x7f6dd757f0ef - std::io::Write::write_fmt::h0876e0f4bddb923c
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/io/mod.rs:1854:15
   7:     0x7f6dd758b714 - std::sys_common::backtrace::_print::h4ae69e83d64cbf46
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7f6dd758b714 - std::sys_common::backtrace::print::h1d97d5831d0262fb
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7f6dd758e4d7 - std::panicking::default_hook::{{closure}}::h39fabb1b3e65f47a
  10:     0x7f6dd758e239 - std::panicking::default_hook::h416520d6bb2cb53f
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/panicking.rs:292:9
  11:     0x7f6dda3266dc - std[3acc11fb688f3d76]::panicking::update_hook::<alloc[408654ec2a1215fa]::boxed::Box<rustc_driver_impl[a7481a600b2f11a0]::install_ice_hook::{closure#0}>>::{closure#0}
  12:     0x7f6dd758ec26 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h2450ecbe2b1c1ea3
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/alloc/src/boxed.rs:2030:9
  13:     0x7f6dd758ec26 - std::panicking::rust_panic_with_hook::h99ef5cbc4b3b0ae4
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/panicking.rs:785:13
  14:     0x7f6dd758e939 - std::panicking::begin_panic_handler::{{closure}}::h2284f60633c08873
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/panicking.rs:651:13
  15:     0x7f6dd758be36 - std::sys_common::backtrace::__rust_end_short_backtrace::h84bc49437da26b5c
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/sys_common/backtrace.rs:171:18
  16:     0x7f6dd758e6c4 - rust_begin_unwind
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/panicking.rs:647:5
  17:     0x7f6dd75daa85 - core::panicking::panic_fmt::hfa0af2309df9012f
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/core/src/panicking.rs:72:14
  18:     0x7f6ddadbf083 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::assemble_alias_bound_candidates_recur::<rustc_middle[9f94bb95ba4eb693]::ty::predicate::TraitPredicate>
  19:     0x7f6ddae37b43 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::assemble_alias_bound_candidates::<rustc_middle[9f94bb95ba4eb693]::ty::predicate::TraitPredicate>
  20:     0x7f6ddadbbf1f - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::assemble_and_evaluate_candidates::<rustc_middle[9f94bb95ba4eb693]::ty::predicate::TraitPredicate>
  21:     0x7f6ddadd419d - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::search_graph::SearchGraph>::with_new_goal::<<rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::evaluate_canonical_goal::{closure#0}::{closure#0}::{closure#0}>::{closure#3}
  22:     0x7f6ddadd0832 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::search_graph::SearchGraph>::with_new_goal::<<rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::evaluate_canonical_goal::{closure#0}::{closure#0}::{closure#0}>
  23:     0x7f6ddadc4d06 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::evaluate_goal
  24:     0x7f6ddae3ab45 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::try_evaluate_added_goals
  25:     0x7f6ddae37fd1 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::evaluate_added_goals_and_make_canonical_response
  26:     0x7f6ddadd31a8 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::search_graph::SearchGraph>::with_new_goal::<<rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::evaluate_canonical_goal::{closure#0}::{closure#0}::{closure#0}>::{closure#3}
  27:     0x7f6ddadd0832 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::search_graph::SearchGraph>::with_new_goal::<<rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::evaluate_canonical_goal::{closure#0}::{closure#0}::{closure#0}>
  28:     0x7f6ddadc4d06 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::evaluate_goal
  29:     0x7f6ddae3ab45 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::try_evaluate_added_goals
  30:     0x7f6ddae37fd1 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::evaluate_added_goals_and_make_canonical_response
  31:     0x7f6ddadd5e54 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::search_graph::SearchGraph>::with_new_goal::<<rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::evaluate_canonical_goal::{closure#0}::{closure#0}::{closure#0}>::{closure#3}
  32:     0x7f6ddadd0832 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::search_graph::SearchGraph>::with_new_goal::<<rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::evaluate_canonical_goal::{closure#0}::{closure#0}::{closure#0}>
  33:     0x7f6ddadc4d06 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::EvalCtxt>::evaluate_goal
  34:     0x7f6ddae3a11e - <rustc_infer[81d54d7e65d62577]::infer::InferCtxt as rustc_trait_selection[c406a89a2b7dc7ed]::solve::eval_ctxt::InferCtxtEvalExt>::evaluate_root_goal
  35:     0x7f6ddadc6a52 - <rustc_trait_selection[c406a89a2b7dc7ed]::solve::fulfill::FulfillmentCtxt as rustc_infer[81d54d7e65d62577]::traits::engine::TraitEngine>::select_where_possible
  36:     0x7f6dd86e7577 - <rustc_infer[81d54d7e65d62577]::infer::InferCtxt as rustc_trait_selection[c406a89a2b7dc7ed]::traits::query::evaluate_obligation::InferCtxtExt>::evaluate_obligation
  37:     0x7f6ddba7bb01 - rustc_trait_selection[c406a89a2b7dc7ed]::traits::coherence::overlap
  38:     0x7f6ddbb5995e - <rustc_middle[9f94bb95ba4eb693]::traits::specialization_graph::Children as rustc_trait_selection[c406a89a2b7dc7ed]::traits::specialize::specialization_graph::ChildrenExt>::insert
  39:     0x7f6ddbb58878 - <rustc_middle[9f94bb95ba4eb693]::traits::specialization_graph::Graph as rustc_trait_selection[c406a89a2b7dc7ed]::traits::specialize::specialization_graph::GraphExt>::insert
  40:     0x7f6ddc0e9dc9 - rustc_trait_selection[c406a89a2b7dc7ed]::traits::specialize::specialization_graph_provider
  41:     0x7f6ddc0e96d9 - rustc_query_impl[60cfa4eef1128f6c]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[60cfa4eef1128f6c]::query_impl::specialization_graph_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle[9f94bb95ba4eb693]::query::erase::Erased<[u8; 8usize]>>
  42:     0x7f6ddb6744e1 - rustc_query_system[30cc65df29d7d3a8]::query::plumbing::try_execute_query::<rustc_query_impl[60cfa4eef1128f6c]::DynamicConfig<rustc_query_system[30cc65df29d7d3a8]::query::caches::DefIdCache<rustc_middle[9f94bb95ba4eb693]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[60cfa4eef1128f6c]::plumbing::QueryCtxt, false>
  43:     0x7f6ddbebdebc - rustc_query_impl[60cfa4eef1128f6c]::query_impl::specialization_graph_of::get_query_non_incr::__rust_end_short_backtrace
  44:     0x7f6ddbebdfbf - rustc_hir_analysis[1799a6ccb3095d3d]::coherence::coherent_trait
  45:     0x7f6ddbebdee3 - rustc_query_impl[60cfa4eef1128f6c]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[60cfa4eef1128f6c]::query_impl::coherent_trait::dynamic_query::{closure#2}::{closure#0}, rustc_middle[9f94bb95ba4eb693]::query::erase::Erased<[u8; 1usize]>>
  46:     0x7f6ddbb128b4 - rustc_query_system[30cc65df29d7d3a8]::query::plumbing::try_execute_query::<rustc_query_impl[60cfa4eef1128f6c]::DynamicConfig<rustc_query_system[30cc65df29d7d3a8]::query::caches::DefIdCache<rustc_middle[9f94bb95ba4eb693]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[60cfa4eef1128f6c]::plumbing::QueryCtxt, false>
  47:     0x7f6ddbd05e4d - rustc_query_impl[60cfa4eef1128f6c]::query_impl::coherent_trait::get_query_non_incr::__rust_end_short_backtrace
  48:     0x7f6ddb7cfd9a - rustc_hir_analysis[1799a6ccb3095d3d]::check_crate
  49:     0x7f6ddbf8bd92 - rustc_interface[57a4cb1189ffa880]::passes::analysis
  50:     0x7f6ddbf8b9df - rustc_query_impl[60cfa4eef1128f6c]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[60cfa4eef1128f6c]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[9f94bb95ba4eb693]::query::erase::Erased<[u8; 1usize]>>
  51:     0x7f6ddc324372 - rustc_query_system[30cc65df29d7d3a8]::query::plumbing::try_execute_query::<rustc_query_impl[60cfa4eef1128f6c]::DynamicConfig<rustc_query_system[30cc65df29d7d3a8]::query::caches::SingleCache<rustc_middle[9f94bb95ba4eb693]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[60cfa4eef1128f6c]::plumbing::QueryCtxt, false>
  52:     0x7f6ddc3240d5 - rustc_query_impl[60cfa4eef1128f6c]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  53:     0x7f6ddc33a582 - rustc_interface[57a4cb1189ffa880]::interface::run_compiler::<core[8df037f8ced6ea1f]::result::Result<(), rustc_span[4a89bdba9678f8e0]::ErrorGuaranteed>, rustc_driver_impl[a7481a600b2f11a0]::run_compiler::{closure#0}>::{closure#0}
  54:     0x7f6ddc3d2b46 - std[3acc11fb688f3d76]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[57a4cb1189ffa880]::util::run_in_thread_with_globals<rustc_interface[57a4cb1189ffa880]::util::run_in_thread_pool_with_globals<rustc_interface[57a4cb1189ffa880]::interface::run_compiler<core[8df037f8ced6ea1f]::result::Result<(), rustc_span[4a89bdba9678f8e0]::ErrorGuaranteed>, rustc_driver_impl[a7481a600b2f11a0]::run_compiler::{closure#0}>::{closure#0}, core[8df037f8ced6ea1f]::result::Result<(), rustc_span[4a89bdba9678f8e0]::ErrorGuaranteed>>::{closure#0}, core[8df037f8ced6ea1f]::result::Result<(), rustc_span[4a89bdba9678f8e0]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[8df037f8ced6ea1f]::result::Result<(), rustc_span[4a89bdba9678f8e0]::ErrorGuaranteed>>
  55:     0x7f6ddc3d2973 - <<std[3acc11fb688f3d76]::thread::Builder>::spawn_unchecked_<rustc_interface[57a4cb1189ffa880]::util::run_in_thread_with_globals<rustc_interface[57a4cb1189ffa880]::util::run_in_thread_pool_with_globals<rustc_interface[57a4cb1189ffa880]::interface::run_compiler<core[8df037f8ced6ea1f]::result::Result<(), rustc_span[4a89bdba9678f8e0]::ErrorGuaranteed>, rustc_driver_impl[a7481a600b2f11a0]::run_compiler::{closure#0}>::{closure#0}, core[8df037f8ced6ea1f]::result::Result<(), rustc_span[4a89bdba9678f8e0]::ErrorGuaranteed>>::{closure#0}, core[8df037f8ced6ea1f]::result::Result<(), rustc_span[4a89bdba9678f8e0]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[8df037f8ced6ea1f]::result::Result<(), rustc_span[4a89bdba9678f8e0]::ErrorGuaranteed>>::{closure#1} as core[8df037f8ced6ea1f]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  56:     0x7f6dd7597eb5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h61e4d902e063b23d
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/alloc/src/boxed.rs:2016:9
  57:     0x7f6dd7597eb5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hfa3eaf4f75275f59
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/alloc/src/boxed.rs:2016:9
  58:     0x7f6dd7597eb5 - std::sys::pal::unix::thread::Thread::new::thread_start::hb901d27f412b0ecd
                               at /rustc/6cc4843512d613f51ec81aba689180c31b0b28b6/library/std/src/sys/pal/unix/thread.rs:108:17
  59:     0x7f6dd73819eb - <unknown>
  60:     0x7f6dd74057cc - <unknown>
  61:                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 1.78.0-nightly (6cc484351 2024-02-10) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z next-solver=coherence -Z dump-mir-dir=dir

query stack during panic:
#0 [specialization_graph_of] building specialization graph of trait `Bop`
#1 [coherent_trait] coherence checking all impls of trait `Bop`
#2 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 3 previous errors

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

@matthiaskrgr matthiaskrgr added I-ICE Issue: The compiler panicked, giving an Internal Compilation Error (ICE) ❄️ T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. C-bug Category: This is a bug. WG-trait-system-refactor The Rustc Trait System Refactor Initiative (-Znext-solver) labels Feb 10, 2024
@rustbot rustbot added the needs-triage This issue may need triage. Remove it if it has been sufficiently triaged. label Feb 10, 2024
@matthiaskrgr
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#120584 cc @compiler-errors

@fmease fmease added F-type_alias_impl_trait `#[feature(type_alias_impl_trait)]` and removed needs-triage This issue may need triage. Remove it if it has been sufficiently triaged. labels Feb 10, 2024
@compiler-errors compiler-errors self-assigned this Feb 10, 2024
@compiler-errors compiler-errors mentioned this issue Feb 10, 2024
Merged
matthiaskrgr added a commit to matthiaskrgr/rust that referenced this issue Feb 12, 2024
@matthiaskrgr
Rollup merge of rust-lang#120899 - compiler-errors:non-wf-alias, r=lcnr
40041af 
Gracefully handle non-WF alias in `assemble_alias_bound_candidates_recur`

See explanation in test. I think it's fine to delay a bug here -- I don't believe we ever construct a non-wf alias on the good path? If so, then we can just remove the delay.

Fixes rust-lang#120891

r? lcnr
@bors bors closed this as completed in 733f93d Feb 12, 2024
rust-timer added a commit to rust-lang-ci/rust that referenced this issue Feb 12, 2024
@rust-timer
Unrolled build for rust-lang#120899
ca34c45 
Rollup merge of rust-lang#120899 - compiler-errors:non-wf-alias, r=lcnr

Gracefully handle non-WF alias in `assemble_alias_bound_candidates_recur`

See explanation in test. I think it's fine to delay a bug here -- I don't believe we ever construct a non-wf alias on the good path? If so, then we can just remove the delay.

Fixes rust-lang#120891

r? lcnr
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C-bug Category: This is a bug. F-type_alias_impl_trait `#[feature(type_alias_impl_trait)]` I-ICE Issue: The compiler panicked, giving an Internal Compilation Error (ICE) ❄️ T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. WG-trait-system-refactor The Rustc Trait System Refactor Initiative (-Znext-solver)
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Gracefully handle non-WF alias in assemble_alias_bound_candidates_recur compiler-errors/rust
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