ICE `explicit deref of non-derefable type`

warning: the feature `pin_ergonomics` is incomplete and may not be safe to use and/or cause compiler crashes
--> code.rs:1:12
|
1 | #![feature(pin_ergonomics)]
|            ^^^^^^^^^^^^^^
|
= note: see issue #130494 <https://github.com/rust-lang/rust/issues/130494> for more information
= note: `#[warn(incomplete_features)]` on by default

warning: unused variable: `x`
--> code.rs:3:28
|
3 | fn patterns <'a>( &pin mut x : Pin< &mut i32 >, &pin const y : Pin < &'a i32>) {} fn main() {}
|                            ^ help: if this is intentional, prefix it with an underscore: `_x`
|
= note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default

warning: unused variable: `y`
--> code.rs:3:60
|
3 | fn patterns <'a>( &pin mut x : Pin< &mut i32 >, &pin const y : Pin < &'a i32>) {} fn main() {}
|                                                            ^ help: if this is intentional, prefix it with an underscore: `_y`

warning: function `patterns` is never used
--> code.rs:3:4
|
3 | fn patterns <'a>( &pin mut x : Pin< &mut i32 >, &pin const y : Pin < &'a i32>) {} fn main() {}
|    ^^^^^^^^
|
= note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default

warning: the following explicit lifetimes could be elided: 'a
--> code.rs:3:14
|
3 | fn patterns <'a>( &pin mut x : Pin< &mut i32 >, &pin const y : Pin < &'a i32>) {} fn main() {}
|              ^^                                                       ^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_lifetimes
= note: `#[warn(clippy::needless_lifetimes)]` on by default
help: elide the lifetimes
|
3 - fn patterns <'a>( &pin mut x : Pin< &mut i32 >, &pin const y : Pin < &'a i32>) {} fn main() {}
3 + fn patterns ( &pin mut x : Pin< &mut i32 >, &pin const y : Pin < &i32>) {} fn main() {}
|

error: internal compiler error: /rustc/3d461af2a23456a2676aadb13b4253c87bdfe28d/compiler/rustc_hir_typeck/src/expr_use_visitor.rs:250:9: explicit deref of non-derefable type
--> code.rs:3:19
|
3 | fn patterns <'a>( &pin mut x : Pin< &mut i32 >, &pin const y : Pin < &'a i32>) {} fn main() {}
|                   ^^^^^^^^^^


thread 'rustc' (579425) panicked at /rustc/3d461af2a23456a2676aadb13b4253c87bdfe28d/compiler/rustc_hir_typeck/src/expr_use_visitor.rs:250:9:
Box<dyn Any>
stack backtrace:
 0:     0x7f4551d25123 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::hfb8348192fc43ebb
 1:     0x7f4552401a9c - core::fmt::write::h97437f5687cea27d
 2:     0x7f4551cda6b6 - std::io::Write::write_fmt::h3d69a328c4d5e4d7
 3:     0x7f4551cf192c - std::panicking::default_hook::{{closure}}::h6aede591faff46a7
 4:     0x7f4551cf1483 - std::panicking::default_hook::h7b4ecf50b930d151
 5:     0x7f4550d34907 - std[3c083641319d47af]::panicking::update_hook::<alloc[b775178a7c8507ec]::boxed::Box<rustc_driver_impl[e2b35ac28e24aea2]::install_ice_hook::{closure#1}>>::{closure#0}
 6:     0x7f4551cf1ce2 - std::panicking::panic_with_hook::hdbcd646c750dedf5
 7:     0x7f4550d6efb1 - std[3c083641319d47af]::panicking::begin_panic::<rustc_errors[f99eb3eef40c1bf3]::ExplicitBug>::{closure#0}
 8:     0x7f4550d61676 - std[3c083641319d47af]::sys::backtrace::__rust_end_short_backtrace::<std[3c083641319d47af]::panicking::begin_panic<rustc_errors[f99eb3eef40c1bf3]::ExplicitBug>::{closure#0}, !>
 9:     0x7f4550d6147f - std[3c083641319d47af]::panicking::begin_panic::<rustc_errors[f99eb3eef40c1bf3]::ExplicitBug>
10:     0x7f4550d8c671 - <rustc_errors[f99eb3eef40c1bf3]::diagnostic::BugAbort as rustc_errors[f99eb3eef40c1bf3]::diagnostic::EmissionGuarantee>::emit_producing_guarantee
11:     0x7f45512e0fec - <rustc_errors[f99eb3eef40c1bf3]::DiagCtxtHandle>::span_bug::<rustc_span[cdbd5621f0a550f6]::span_encoding::Span, alloc[b775178a7c8507ec]::string::String>
12:     0x7f4551303866 - rustc_middle[92ef52462bc1851d]::util::bug::opt_span_bug_fmt::<rustc_span[cdbd5621f0a550f6]::span_encoding::Span>::{closure#0}
13:     0x7f4551303b52 - rustc_middle[92ef52462bc1851d]::ty::context::tls::with_opt::<rustc_middle[92ef52462bc1851d]::util::bug::opt_span_bug_fmt<rustc_span[cdbd5621f0a550f6]::span_encoding::Span>::{closure#0}, !>::{closure#0}
14:     0x7f45512f406b - rustc_middle[92ef52462bc1851d]::ty::context::tls::with_context_opt::<rustc_middle[92ef52462bc1851d]::ty::context::tls::with_opt<rustc_middle[92ef52462bc1851d]::util::bug::opt_span_bug_fmt<rustc_span[cdbd5621f0a550f6]::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
15:     0x7f454f501718 - rustc_middle[92ef52462bc1851d]::util::bug::span_bug_fmt::<rustc_span[cdbd5621f0a550f6]::span_encoding::Span>
16:     0x55656206ed4c - <(&rustc_lint[acdcb7f2f12aadef]::context::LateContext, rustc_span[cdbd5621f0a550f6]::def_id::LocalDefId) as rustc_hir_typeck[66a832bac098b42e]::expr_use_visitor::TypeInformationCtxt>::report_bug::<&str>
17:     0x556562163a19 - <rustc_hir_typeck[66a832bac098b42e]::expr_use_visitor::ExprUseVisitor<(&rustc_lint[acdcb7f2f12aadef]::context::LateContext, rustc_span[cdbd5621f0a550f6]::def_id::LocalDefId), clippy_lints[3920a25f0125aee3]::replace_box::MovedVariablesCtxt>>::cat_deref
18:     0x556561f5f8cb - <rustc_hir_typeck[66a832bac098b42e]::expr_use_visitor::ExprUseVisitor<(&rustc_lint[acdcb7f2f12aadef]::context::LateContext, rustc_span[cdbd5621f0a550f6]::def_id::LocalDefId), &mut clippy_lints[3920a25f0125aee3]::escape::EscapeDelegate>>::cat_pattern::<<rustc_hir_typeck[66a832bac098b42e]::expr_use_visitor::ExprUseVisitor<(&rustc_lint[acdcb7f2f12aadef]::context::LateContext, rustc_span[cdbd5621f0a550f6]::def_id::LocalDefId), &mut clippy_lints[3920a25f0125aee3]::escape::EscapeDelegate>>::walk_pat::{closure#0}>
19:     0x55656232a7c5 - <clippy_lints[3920a25f0125aee3]::escape::BoxedLocal as rustc_lint[acdcb7f2f12aadef]::passes::LateLintPass>::check_fn
20:     0x7f455127cfd8 - <rustc_lint[acdcb7f2f12aadef]::late::LateContextAndPass<rustc_lint[acdcb7f2f12aadef]::late::RuntimeCombinedLateLintPass> as rustc_hir[b7c24ccb62dd1aaf]::intravisit::Visitor>::visit_fn
21:     0x7f455128d25a - <rustc_lint[acdcb7f2f12aadef]::late::LateContextAndPass<rustc_lint[acdcb7f2f12aadef]::late::RuntimeCombinedLateLintPass> as rustc_hir[b7c24ccb62dd1aaf]::intravisit::Visitor>::visit_nested_item
22:     0x7f4551216549 - <rustc_lint[acdcb7f2f12aadef]::late::LateContextAndPass<rustc_lint[acdcb7f2f12aadef]::late::RuntimeCombinedLateLintPass>>::process_mod
23:     0x7f455317cfad - rustc_lint[acdcb7f2f12aadef]::late::check_crate::{closure#0}
24:     0x7f455317d26d - rustc_lint[acdcb7f2f12aadef]::late::check_crate
25:     0x7f45525ea06a - rustc_interface[f4dc2643b08c82c2]::passes::analysis
26:     0x7f45525e97f5 - rustc_query_impl[189616ec442d20ff]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[189616ec442d20ff]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[92ef52462bc1851d]::query::erase::Erased<[u8; 0usize]>>
27:     0x7f455348979a - rustc_query_system[76ea79e72d8eff41]::query::plumbing::try_execute_query::<rustc_query_impl[189616ec442d20ff]::DynamicConfig<rustc_query_system[76ea79e72d8eff41]::query::caches::SingleCache<rustc_middle[92ef52462bc1851d]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[189616ec442d20ff]::plumbing::QueryCtxt, false>
28:     0x7f45534893d4 - rustc_query_impl[189616ec442d20ff]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
29:     0x7f455372cb90 - <rustc_interface[f4dc2643b08c82c2]::passes::create_and_enter_global_ctxt<core[161168e1bae70b66]::option::Option<rustc_interface[f4dc2643b08c82c2]::queries::Linker>, rustc_driver_impl[e2b35ac28e24aea2]::run_compiler::{closure#0}::{closure#2}>::{closure#2} as core[161168e1bae70b66]::ops::function::FnOnce<(&rustc_session[90c76d851aa26706]::session::Session, rustc_middle[92ef52462bc1851d]::ty::context::CurrentGcx, alloc[b775178a7c8507ec]::sync::Arc<rustc_data_structures[289d2f4bcfffdd46]::jobserver::Proxy>, &std[3c083641319d47af]::sync::once_lock::OnceLock<rustc_middle[92ef52462bc1851d]::ty::context::GlobalCtxt>, &rustc_data_structures[289d2f4bcfffdd46]::sync::worker_local::WorkerLocal<rustc_middle[92ef52462bc1851d]::arena::Arena>, &rustc_data_structures[289d2f4bcfffdd46]::sync::worker_local::WorkerLocal<rustc_hir[b7c24ccb62dd1aaf]::Arena>, rustc_driver_impl[e2b35ac28e24aea2]::run_compiler::{closure#0}::{closure#2})>>::call_once::{shim:vtable#0}
30:     0x7f4553517005 - rustc_interface[f4dc2643b08c82c2]::interface::run_compiler::<(), rustc_driver_impl[e2b35ac28e24aea2]::run_compiler::{closure#0}>::{closure#1}
31:     0x7f45534f8ffa - std[3c083641319d47af]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[f4dc2643b08c82c2]::util::run_in_thread_with_globals<rustc_interface[f4dc2643b08c82c2]::util::run_in_thread_pool_with_globals<rustc_interface[f4dc2643b08c82c2]::interface::run_compiler<(), rustc_driver_impl[e2b35ac28e24aea2]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
32:     0x7f45534f8ce8 - <<std[3c083641319d47af]::thread::Builder>::spawn_unchecked_<rustc_interface[f4dc2643b08c82c2]::util::run_in_thread_with_globals<rustc_interface[f4dc2643b08c82c2]::util::run_in_thread_pool_with_globals<rustc_interface[f4dc2643b08c82c2]::interface::run_compiler<(), rustc_driver_impl[e2b35ac28e24aea2]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[161168e1bae70b66]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
33:     0x7f45534fec2f - std::sys::thread::unix::Thread::new::thread_start::he2d9ab7043ddc2b3
34:     0x7f454ce969cb - <unknown>
35:     0x7f454cf1aa0c - <unknown>
36:                0x0 - <unknown>

note: we would appreciate a bug report: https://github.com/rust-lang/rust-clippy/issues/new?template=ice.yml

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

note: please attach the file at `/home/matthias/vcs/github/CRED/rustc-ice-2025-11-19T21_09_53-579408.txt` to your bug report

query stack during panic:
#0 [analysis] running analysis passes on crate `code`
end of query stack
note: Clippy version: clippy 0.1.93 (3d461af2a2 2025-11-18)

error: aborting due to 1 previous error; 5 warnings emitted