ICE: non_lifetime_binders unexpected bound ty in binder: BoundTy {...}

[matthiaskrgr]

Code

#![feature(non_lifetime_binders)]

fn main()  {
    for<main> || -> & main  {};
}

Meta

rustc --version --verbose:

rustc 1.69.0-nightly (f4f5fc3e5 2023-02-17)
binary: rustc
commit-hash: f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3
commit-date: 2023-02-17
host: x86_64-unknown-linux-gnu
release: 1.69.0-nightly
LLVM version: 15.0.7

Error output

error[E0637]: `&` without an explicit lifetime name cannot be used here
 --> 2f364877ae32a51855925609c897ffa9f739c835.rs:2:21
  |
2 |     for<main> || -> & main  {};
  |                     ^ explicit lifetime name needed here

error[E0658]: `for<...>` binders for closures are experimental
 --> 2f364877ae32a51855925609c897ffa9f739c835.rs:2:5
  |
2 |     for<main> || -> & main  {};
  |     ^^^^^^^^^
  |
  = note: see issue #97362 <https://github.com/rust-lang/rust/issues/97362> for more information
  = help: add `#![feature(closure_lifetime_binder)]` to the crate attributes to enable
  = help: consider removing `for<...>`

warning: the feature `non_lifetime_binders` is incomplete and may not be safe to use and/or cause compiler crashes
 --> <crate attribute>:1:9
  |
1 | feature(non_lifetime_binders)
  |         ^^^^^^^^^^^^^^^^^^^^
  |
  = note: see issue #1 <https://github.com/rust-lang/rust/issues/1> for more information
  = note: `#[warn(incomplete_features)]` on by default

warning: type parameter `main` should have an upper camel case name
 --> 2f364877ae32a51855925609c897ffa9f739c835.rs:2:9
  |
2 |     for<main> || -> & main  {};
  |         ^^^^ help: convert the identifier to upper camel case: `Main`
  |
  = note: `#[warn(non_camel_case_types)]` on by default

Backtrace

error: internal compiler error: /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/compiler/rustc_middle/src/ty/fold.rs:306:33: unexpected bound ty in binder: BoundTy { var: 0, kind: Param(DefId(0:5 ~ 2f364877ae32a51855925609c897ffa9f739c835[5b1e]::main::{closure#0}::main), "main") }

thread 'rustc' panicked at 'Box<dyn Any>', /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/compiler/rustc_errors/src/lib.rs:1642:9
stack backtrace:
   0:     0x7fe41bb6aa5a - std::backtrace_rs::backtrace::libunwind::trace::hebe09041f884c65d
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7fe41bb6aa5a - std::backtrace_rs::backtrace::trace_unsynchronized::h546f6c63cbbce5a9
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7fe41bb6aa5a - std::sys_common::backtrace::_print_fmt::h2559cb0cfed7a617
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/std/src/sys_common/backtrace.rs:65:5
   3:     0x7fe41bb6aa5a - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h1fb4eaaaafa2d72a
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7fe41bbca9ae - core::fmt::write::hbaef4432b3c9d07b
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/core/src/fmt/mod.rs:1232:17
   5:     0x7fe41bb5ae05 - std::io::Write::write_fmt::h1f8dce362441faaa
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/std/src/io/mod.rs:1684:15
   6:     0x7fe41bb6a825 - std::sys_common::backtrace::_print::hc0e92ab849a4f4e1
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/std/src/sys_common/backtrace.rs:47:5
   7:     0x7fe41bb6a825 - std::sys_common::backtrace::print::h878cd11684ebdec3
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/std/src/sys_common/backtrace.rs:34:9
   8:     0x7fe41bb6d59f - std::panicking::default_hook::{{closure}}::h2ea8a6875aa6312d
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/std/src/panicking.rs:267:22
   9:     0x7fe41bb6d2db - std::panicking::default_hook::h9e42277a84072188
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/std/src/panicking.rs:286:9
  10:     0x7fe41ee6e7b4 - <rustc_driver_impl[afa3c304d692170b]::DEFAULT_HOOK::{closure#0}::{closure#0} as core[ebab21900c9c0a2]::ops::function::FnOnce<(&core[ebab21900c9c0a2]::panic::panic_info::PanicInfo,)>>::call_once::{shim:vtable#0}
  11:     0x7fe41bb6dddd - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h2c34f129ed413128
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/alloc/src/boxed.rs:2002:9
  12:     0x7fe41bb6dddd - std::panicking::rust_panic_with_hook::h4c799b8c4fc0a70b
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/std/src/panicking.rs:692:13
  13:     0x7fe41f4274a1 - std[dc63ca99f82ce43d]::panicking::begin_panic::<rustc_errors[faa449d960b5ce55]::ExplicitBug>::{closure#0}
  14:     0x7fe41f41f116 - std[dc63ca99f82ce43d]::sys_common::backtrace::__rust_end_short_backtrace::<std[dc63ca99f82ce43d]::panicking::begin_panic<rustc_errors[faa449d960b5ce55]::ExplicitBug>::{closure#0}, !>
  15:     0x7fe41f379fe6 - std[dc63ca99f82ce43d]::panicking::begin_panic::<rustc_errors[faa449d960b5ce55]::ExplicitBug>
  16:     0x7fe41f41ed96 - std[dc63ca99f82ce43d]::panic::panic_any::<rustc_errors[faa449d960b5ce55]::ExplicitBug>
  17:     0x7fe41f41d906 - <rustc_errors[faa449d960b5ce55]::HandlerInner>::bug::<&alloc[d840872249f3dc84]::string::String>
  18:     0x7fe41f41d5d0 - <rustc_errors[faa449d960b5ce55]::Handler>::bug::<&alloc[d840872249f3dc84]::string::String>
  19:     0x7fe41f484b1b - rustc_middle[6caff671bb338453]::util::bug::opt_span_bug_fmt::<rustc_span[1010a352e5466fad]::span_encoding::Span>::{closure#0}
  20:     0x7fe41f4842da - rustc_middle[6caff671bb338453]::ty::context::tls::with_opt::<rustc_middle[6caff671bb338453]::util::bug::opt_span_bug_fmt<rustc_span[1010a352e5466fad]::span_encoding::Span>::{closure#0}, !>::{closure#0}
  21:     0x7fe41f4842a6 - rustc_middle[6caff671bb338453]::ty::context::tls::with_context_opt::<rustc_middle[6caff671bb338453]::ty::context::tls::with_opt<rustc_middle[6caff671bb338453]::util::bug::opt_span_bug_fmt<rustc_span[1010a352e5466fad]::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
  22:     0x7fe41f484a66 - rustc_middle[6caff671bb338453]::util::bug::opt_span_bug_fmt::<rustc_span[1010a352e5466fad]::span_encoding::Span>
  23:     0x7fe41d141083 - rustc_middle[6caff671bb338453]::util::bug::bug_fmt
  24:     0x7fe41f0d445c - <rustc_middle[6caff671bb338453]::ty::context::TyCtxt>::replace_late_bound_regions_uncached::<rustc_middle[6caff671bb338453]::ty::sty::FnSig, <rustc_middle[6caff671bb338453]::ty::context::TyCtxt>::replace_late_bound_regions<rustc_middle[6caff671bb338453]::ty::sty::FnSig, <rustc_middle[6caff671bb338453]::ty::context::TyCtxt>::erase_late_bound_regions<rustc_middle[6caff671bb338453]::ty::sty::FnSig>::{closure#0}>::{closure#0}>::{closure#0}
  25:     0x7fe41d292e90 - <rustc_middle[6caff671bb338453]::ty::fold::BoundVarReplacer<rustc_middle[6caff671bb338453]::ty::fold::FnMutDelegate> as rustc_type_ir[b1287c9e7106c79]::fold::FallibleTypeFolder<rustc_middle[6caff671bb338453]::ty::context::TyCtxt>>::try_fold_ty
  26:     0x7fe41d51c1a7 - <rustc_middle[6caff671bb338453]::ty::Ty as rustc_type_ir[b1287c9e7106c79]::fold::TypeSuperFoldable<rustc_middle[6caff671bb338453]::ty::context::TyCtxt>>::super_fold_with::<rustc_middle[6caff671bb338453]::ty::fold::BoundVarReplacer<rustc_middle[6caff671bb338453]::ty::fold::FnMutDelegate>>
  27:     0x7fe41d51b865 - <&rustc_middle[6caff671bb338453]::ty::list::List<rustc_middle[6caff671bb338453]::ty::Ty> as rustc_type_ir[b1287c9e7106c79]::fold::TypeFoldable<rustc_middle[6caff671bb338453]::ty::context::TyCtxt>>::try_fold_with::<rustc_middle[6caff671bb338453]::ty::fold::BoundVarReplacer<rustc_middle[6caff671bb338453]::ty::fold::FnMutDelegate>>
  28:     0x7fe41d28319b - <rustc_hir_typeck[59924f8822ff3497]::fn_ctxt::FnCtxt>::closure_sigs
  29:     0x7fe41d2811c2 - <rustc_hir_typeck[59924f8822ff3497]::fn_ctxt::FnCtxt>::check_expr_closure
  30:     0x7fe41d1fedce - <rustc_hir_typeck[59924f8822ff3497]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
  31:     0x7fe41d224e45 - <rustc_hir_typeck[59924f8822ff3497]::fn_ctxt::FnCtxt>::check_block_with_expected
  32:     0x7fe41d1fb52e - <rustc_hir_typeck[59924f8822ff3497]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
  33:     0x7fe41d5b689b - <rustc_hir_typeck[59924f8822ff3497]::fn_ctxt::FnCtxt>::check_return_expr
  34:     0x7fe41d5aeb12 - rustc_hir_typeck[59924f8822ff3497]::check::check_fn
  35:     0x7fe41d598ef2 - <rustc_hir_typeck[59924f8822ff3497]::inherited::InheritedBuilder>::enter::<rustc_hir_typeck[59924f8822ff3497]::typeck_with_fallback<rustc_hir_typeck[59924f8822ff3497]::typeck::{closure#0}>::{closure#0}::{closure#1}, &rustc_middle[6caff671bb338453]::ty::typeck_results::TypeckResults>
  36:     0x7fe41d58da16 - rustc_hir_typeck[59924f8822ff3497]::typeck
  37:     0x7fe41d58c113 - rustc_query_system[5ff89444bbfc32f5]::query::plumbing::try_execute_query::<rustc_query_impl[ef929ccf3c28623b]::queries::typeck, rustc_query_impl[ef929ccf3c28623b]::plumbing::QueryCtxt>
  38:     0x7fe41e5f0f8b - rustc_data_structures[cd995ba5556f5758]::sync::par_for_each_in::<&[rustc_span[1010a352e5466fad]::def_id::LocalDefId], <rustc_middle[6caff671bb338453]::hir::map::Map>::par_body_owners<rustc_hir_typeck[59924f8822ff3497]::typeck_item_bodies::{closure#0}>::{closure#0}>
  39:     0x7fe41e5f0dcf - rustc_hir_typeck[59924f8822ff3497]::typeck_item_bodies
  40:     0x7fe41e46fca3 - rustc_query_system[5ff89444bbfc32f5]::query::plumbing::try_execute_query::<rustc_query_impl[ef929ccf3c28623b]::queries::typeck_item_bodies, rustc_query_impl[ef929ccf3c28623b]::plumbing::QueryCtxt>
  41:     0x7fe41e86e59b - <rustc_query_impl[ef929ccf3c28623b]::Queries as rustc_middle[6caff671bb338453]::ty::query::QueryEngine>::typeck_item_bodies
  42:     0x7fe41d3136a3 - <rustc_session[66793dd6b8780a4a]::session::Session>::time::<(), rustc_hir_analysis[257f64c795d1d076]::check_crate::{closure#7}>
  43:     0x7fe41d3106a2 - rustc_hir_analysis[257f64c795d1d076]::check_crate
  44:     0x7fe41d306062 - rustc_interface[686dab9608bc6033]::passes::analysis
  45:     0x7fe41e663d92 - rustc_query_system[5ff89444bbfc32f5]::query::plumbing::try_execute_query::<rustc_query_impl[ef929ccf3c28623b]::queries::analysis, rustc_query_impl[ef929ccf3c28623b]::plumbing::QueryCtxt>
  46:     0x7fe41e867e2a - <rustc_query_impl[ef929ccf3c28623b]::Queries as rustc_middle[6caff671bb338453]::ty::query::QueryEngine>::analysis
  47:     0x7fe41e080303 - <rustc_interface[686dab9608bc6033]::queries::QueryResult<&rustc_middle[6caff671bb338453]::ty::context::GlobalCtxt>>::enter::<core[ebab21900c9c0a2]::result::Result<(), rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>, rustc_driver_impl[afa3c304d692170b]::run_compiler::{closure#1}::{closure#2}::{closure#3}>
  48:     0x7fe41e07f4d4 - <rustc_interface[686dab9608bc6033]::interface::Compiler>::enter::<rustc_driver_impl[afa3c304d692170b]::run_compiler::{closure#1}::{closure#2}, core[ebab21900c9c0a2]::result::Result<core[ebab21900c9c0a2]::option::Option<rustc_interface[686dab9608bc6033]::queries::Linker>, rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>>
  49:     0x7fe41e07a6f4 - rustc_span[1010a352e5466fad]::with_source_map::<core[ebab21900c9c0a2]::result::Result<(), rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>, rustc_interface[686dab9608bc6033]::interface::run_compiler<core[ebab21900c9c0a2]::result::Result<(), rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>, rustc_driver_impl[afa3c304d692170b]::run_compiler::{closure#1}>::{closure#0}::{closure#0}>
  50:     0x7fe41e07a204 - <scoped_tls[d487b98c36b0d138]::ScopedKey<rustc_span[1010a352e5466fad]::SessionGlobals>>::set::<rustc_interface[686dab9608bc6033]::interface::run_compiler<core[ebab21900c9c0a2]::result::Result<(), rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>, rustc_driver_impl[afa3c304d692170b]::run_compiler::{closure#1}>::{closure#0}, core[ebab21900c9c0a2]::result::Result<(), rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>>
  51:     0x7fe41e079902 - std[dc63ca99f82ce43d]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[686dab9608bc6033]::util::run_in_thread_pool_with_globals<rustc_interface[686dab9608bc6033]::interface::run_compiler<core[ebab21900c9c0a2]::result::Result<(), rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>, rustc_driver_impl[afa3c304d692170b]::run_compiler::{closure#1}>::{closure#0}, core[ebab21900c9c0a2]::result::Result<(), rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[ebab21900c9c0a2]::result::Result<(), rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>>
  52:     0x7fe41e0796ac - <<std[dc63ca99f82ce43d]::thread::Builder>::spawn_unchecked_<rustc_interface[686dab9608bc6033]::util::run_in_thread_pool_with_globals<rustc_interface[686dab9608bc6033]::interface::run_compiler<core[ebab21900c9c0a2]::result::Result<(), rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>, rustc_driver_impl[afa3c304d692170b]::run_compiler::{closure#1}>::{closure#0}, core[ebab21900c9c0a2]::result::Result<(), rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[ebab21900c9c0a2]::result::Result<(), rustc_errors[faa449d960b5ce55]::ErrorGuaranteed>>::{closure#1} as core[ebab21900c9c0a2]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  53:     0x7fe41bb77c63 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h9fd36c4a0ba5b15d
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/alloc/src/boxed.rs:1988:9
  54:     0x7fe41bb77c63 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hd37d267854c7434f
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/alloc/src/boxed.rs:1988:9
  55:     0x7fe41bb77c63 - std::sys::unix::thread::Thread::new::thread_start::h1ff24d5a09f2a8be
                               at /rustc/f4f5fc3e5cc70b7a43bf7b518c455f3d9bada9e3/library/std/src/sys/unix/thread.rs:108:17
  56:     0x7fe41b907bb5 - <unknown>
  57:     0x7fe41b989d90 - <unknown>
  58:                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: rustc 1.69.0-nightly (f4f5fc3e5 2023-02-17) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z crate-attr=feature(non_lifetime_binders)

query stack during panic:
#0 [typeck] type-checking `main`
#1 [typeck_item_bodies] type-checking all item bodies
#2 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 3 previous errors; 2 warnings emitted

Some errors have detailed explanations: E0637, E0658.
For more information about an error, try `rustc --explain E0637`.