ICE related to f16 / f128 #123074

warning: unused variable: `b`
 --> src/main.rs:9:9
  |
9 |     let b = unsafe { foo(a) };
  |         ^ help: if this is intentional, prefix it with an underscore: `_b`
  |
  = note: `#[warn(unused_variables)]` on by default

note: no errors encountered even though delayed bugs were created

note: those delayed bugs will now be shown as internal compiler errors

error: internal compiler error: error performing ParamEnvAnd { param_env: ParamEnv { caller_bounds: [], reveal: UserFacing }, value: ProvePredicate { predicate: Binder { value: TraitPredicate(<f16 as std::marker::Copy>, polarity:Positive), bound_vars: [] } } }
 --> src/main.rs:9:26
  |
9 |     let b = unsafe { foo(a) };
  |                          ^
  |
note: delayed at /rustc/5f2c7d2bfd46cad00352ab7cd66242077e2e518c/compiler/rustc_trait_selection/src/traits/query/type_op/mod.rs:165:29
         0: <rustc_errors::DiagCtxtInner>::emit_diagnostic
         1: <rustc_errors::DiagCtxt>::emit_diagnostic
         2: <rustc_span::ErrorGuaranteed as rustc_errors::diagnostic::EmissionGuarantee>::emit_producing_guarantee
         3: <rustc_borrowck::type_check::TypeChecker>::prove_trait_ref
         4: <rustc_borrowck::type_check::TypeVerifier as rustc_middle::mir::visit::Visitor>::visit_operand
         5: <rustc_borrowck::type_check::TypeVerifier as rustc_middle::mir::visit::Visitor>::visit_body
         6: rustc_borrowck::type_check::type_check
         7: rustc_borrowck::nll::compute_regions
         8: rustc_borrowck::do_mir_borrowck
         9: rustc_borrowck::mir_borrowck
        10: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_borrowck::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
        11: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
        12: rustc_query_impl::query_impl::mir_borrowck::get_query_non_incr::__rust_end_short_backtrace
        13: rustc_interface::passes::analysis
        14: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
        15: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 1]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false>
        16: rustc_query_impl::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
        17: rustc_interface::interface::run_compiler::<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}
        18: std::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>
        19: <<std::thread::Builder>::spawn_unchecked_<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
        20: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
                   at /rustc/5f2c7d2bfd46cad00352ab7cd66242077e2e518c/library/alloc/src/boxed.rs:2015:9
        21: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
                   at /rustc/5f2c7d2bfd46cad00352ab7cd66242077e2e518c/library/alloc/src/boxed.rs:2015:9
        22: std::sys::pal::unix::thread::Thread::new::thread_start
                   at /rustc/5f2c7d2bfd46cad00352ab7cd66242077e2e518c/library/std/src/sys/pal/unix/thread.rs:108:17
        23: start_thread
        24: clone
 --> src/main.rs:9:26
  |
9 |     let b = unsafe { foo(a) };
  |                          ^

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 attach the file at `/playground/rustc-ice-2024-03-26T04_39_23-19.txt` to your bug report

note: compiler flags: --crate-type bin -C embed-bitcode=no -C codegen-units=1 -C debuginfo=2

note: some of the compiler flags provided by cargo are hidden

query stack during panic:
end of query stack
warning: `playground` (bin "playground") generated 1 warning
error: could not compile `playground` (bin "playground"); 1 warning emitted