ICE: inherent_associated_types: Unexpected parameter Type(S<'a>) when substituting in region 'a (index=0) with -Zdump-mir=all

[matthiaskrgr]

Code

rustc -Zdump-mir=all late-bound-regions.rs

#![feature(inherent_associated_types)]

type Function = for<'a> fn(&'a i32) -> S<'a>::P;

struct S<'a>(&'a ());

impl<'a> S<'a> {
    type P = &'a i32;
}

fn ret_ref_local<'e>() -> &'e i32 {
    let f: Function = |x| x;

    let local = 0;
    f(&local) 
}

fn main() {}

Meta

rustc --version --verbose:

rustc 1.71.0-nightly (2f2c438dc 2023-05-08)
binary: rustc
commit-hash: 2f2c438dce75d8cc532c3baa849eeddc0901802c
commit-date: 2023-05-08
host: x86_64-unknown-linux-gnu
release: 1.71.0-nightly
LLVM version: 16.0.2

Error output

<output>

Backtrace

error: internal compiler error: compiler/rustc_middle/src/ty/subst.rs:810:13: Unexpected parameter Type(S<'a>) when substituting in region 'a (index=0)

thread 'rustc' panicked at 'Box<dyn Any>', /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/compiler/rustc_errors/src/lib.rs:1650:9
stack backtrace:
   0:     0x7ff285946361 - std::backtrace_rs::backtrace::libunwind::trace::he9e9030cf5bcddaa
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7ff285946361 - std::backtrace_rs::backtrace::trace_unsynchronized::hb5e44a77ff0586eb
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7ff285946361 - std::sys_common::backtrace::_print_fmt::h38e8723c5d83f22f
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/std/src/sys_common/backtrace.rs:65:5
   3:     0x7ff285946361 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h5e394c4b1f1cb045
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7ff2859a66ff - core::fmt::rt::Argument::fmt::ha5dde4cb71578cc2
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/fmt/rt.rs:138:9
   5:     0x7ff2859a66ff - core::fmt::write::hb1413899fd777907
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/fmt/mod.rs:1094:21
   6:     0x7ff2859395c1 - std::io::Write::write_fmt::h08b4eac68313bb0d
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/std/src/io/mod.rs:1712:15
   7:     0x7ff285946175 - std::sys_common::backtrace::_print::h2bb25f41b1777226
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7ff285946175 - std::sys_common::backtrace::print::ha21981aa5a1c5802
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7ff285948e07 - std::panicking::default_hook::{{closure}}::h603ce04329232051
  10:     0x7ff285948bf4 - std::panicking::default_hook::hd4285764fbdb24e1
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/std/src/panicking.rs:288:9
  11:     0x7ff2847bf94b - <rustc_driver_impl[27c68de0ac55b06a]::install_ice_hook::{closure#0} as core[3afeaedfb140cde7]::ops::function::FnOnce<(&core[3afeaedfb140cde7]::panic::panic_info::PanicInfo,)>>::call_once::{shim:vtable#0}
  12:     0x7ff285949527 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h401f21a7538313bc
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/alloc/src/boxed.rs:1999:9
  13:     0x7ff285949527 - std::panicking::rust_panic_with_hook::h2322eda2481f33bc
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/std/src/panicking.rs:695:13
  14:     0x7ff284cae031 - std[53b54636b4f52653]::panicking::begin_panic::<rustc_errors[2afb0e2cc7c4c42d]::ExplicitBug>::{closure#0}
  15:     0x7ff284caa7e6 - std[53b54636b4f52653]::sys_common::backtrace::__rust_end_short_backtrace::<std[53b54636b4f52653]::panicking::begin_panic<rustc_errors[2afb0e2cc7c4c42d]::ExplicitBug>::{closure#0}, !>
  16:     0x7ff284caa6d6 - std[53b54636b4f52653]::panicking::begin_panic::<rustc_errors[2afb0e2cc7c4c42d]::ExplicitBug>
  17:     0x7ff284ca5264 - <rustc_errors[2afb0e2cc7c4c42d]::HandlerInner>::bug::<alloc[a4f318becb59a05]::string::String>
  18:     0x7ff284ca4d76 - <rustc_errors[2afb0e2cc7c4c42d]::Handler>::bug::<alloc[a4f318becb59a05]::string::String>
  19:     0x7ff284d31bac - rustc_middle[232bd29a687eeda3]::util::bug::opt_span_bug_fmt::<rustc_span[811089187935bcb6]::span_encoding::Span>::{closure#0}
  20:     0x7ff284d3137a - rustc_middle[232bd29a687eeda3]::ty::context::tls::with_opt::<rustc_middle[232bd29a687eeda3]::util::bug::opt_span_bug_fmt<rustc_span[811089187935bcb6]::span_encoding::Span>::{closure#0}, !>::{closure#0}
  21:     0x7ff284d3134a - rustc_middle[232bd29a687eeda3]::ty::context::tls::with_context_opt::<rustc_middle[232bd29a687eeda3]::ty::context::tls::with_opt<rustc_middle[232bd29a687eeda3]::util::bug::opt_span_bug_fmt<rustc_span[811089187935bcb6]::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
  22:     0x7ff2829c8f8d - rustc_middle[232bd29a687eeda3]::util::bug::bug_fmt
  23:     0x7ff284cb7731 - <rustc_middle[232bd29a687eeda3]::ty::subst::SubstFolder as rustc_type_ir[cc09a4b81b2ca552]::fold::TypeFolder<rustc_middle[232bd29a687eeda3]::ty::context::TyCtxt>>::fold_region::region_param_invalid
  24:     0x7ff2827ae0c9 - <rustc_middle[232bd29a687eeda3]::ty::subst::GenericArg as rustc_type_ir[cc09a4b81b2ca552]::fold::TypeFoldable<rustc_middle[232bd29a687eeda3]::ty::context::TyCtxt>>::try_fold_with::<rustc_middle[232bd29a687eeda3]::ty::subst::SubstFolder>
  25:     0x7ff2827abe46 - <rustc_middle[232bd29a687eeda3]::ty::Ty as rustc_type_ir[cc09a4b81b2ca552]::fold::TypeSuperFoldable<rustc_middle[232bd29a687eeda3]::ty::context::TyCtxt>>::super_fold_with::<rustc_middle[232bd29a687eeda3]::ty::subst::SubstFolder>
  26:     0x7ff28290ae4b - <rustc_middle[232bd29a687eeda3]::ty::print::pretty::FmtPrinter as rustc_middle[232bd29a687eeda3]::ty::print::Printer>::print_def_path
  27:     0x7ff28290a7c6 - <rustc_middle[232bd29a687eeda3]::ty::print::pretty::FmtPrinter as rustc_middle[232bd29a687eeda3]::ty::print::Printer>::print_def_path
  28:     0x7ff282907f2b - <rustc_middle[232bd29a687eeda3]::ty::print::pretty::FmtPrinter as rustc_middle[232bd29a687eeda3]::ty::print::pretty::PrettyPrinter>::pretty_print_type
  29:     0x7ff284d38036 - <rustc_middle[232bd29a687eeda3]::ty::print::pretty::FmtPrinter as rustc_middle[232bd29a687eeda3]::ty::print::pretty::PrettyPrinter>::pretty_fn_sig
  30:     0x7ff284cfae2f - <rustc_middle[232bd29a687eeda3]::ty::sty::FnSig as rustc_middle[232bd29a687eeda3]::ty::print::Print<rustc_middle[232bd29a687eeda3]::ty::print::pretty::FmtPrinter>>::print
  31:     0x7ff284d409f2 - <rustc_middle[232bd29a687eeda3]::ty::print::pretty::FmtPrinter>::pretty_in_binder::<rustc_middle[232bd29a687eeda3]::ty::sty::FnSig>
  32:     0x7ff28290903b - <rustc_middle[232bd29a687eeda3]::ty::print::pretty::FmtPrinter as rustc_middle[232bd29a687eeda3]::ty::print::pretty::PrettyPrinter>::pretty_print_type
  33:     0x7ff28290752c - <rustc_middle[232bd29a687eeda3]::ty::Ty as core[3afeaedfb140cde7]::fmt::Display>::fmt
  34:     0x7ff284d51a28 - <rustc_middle[232bd29a687eeda3]::ty::Ty as core[3afeaedfb140cde7]::fmt::Debug>::fmt
  35:     0x7ff2859a360c - core::fmt::builders::DebugTuple::field::{{closure}}::hae8bf7adeee9f6a5
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/fmt/builders.rs:322:17
  36:     0x7ff2859a360c - core::result::Result<T,E>::and_then::h929eb9fc8e20a049
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/result.rs:1319:22
  37:     0x7ff2859a360c - core::fmt::builders::DebugTuple::field::h3d7fca7c97960413
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/fmt/builders.rs:309:35
  38:     0x7ff2859a7b1b - core::fmt::Formatter::debug_tuple_field1_finish::h4e6f73694bf6c84f
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/fmt/mod.rs:2023:9
  39:     0x7ff284c64cea - <rustc_middle[232bd29a687eeda3]::ty::typeck_results::UserType as core[3afeaedfb140cde7]::fmt::Debug>::fmt
  40:     0x7ff2859a3379 - core::fmt::builders::DebugStruct::field::{{closure}}::h473ac448a7c4116a
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/fmt/builders.rs:141:17
  41:     0x7ff2859a3379 - core::result::Result<T,E>::and_then::hbb9e091b5a5e90dc
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/result.rs:1319:22
  42:     0x7ff2859a3379 - core::fmt::builders::DebugStruct::field::h4e3ae4a6f27f2d47
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/fmt/builders.rs:124:35
  43:     0x7ff2859a7696 - core::fmt::Formatter::debug_struct_field3_finish::h38cd8cf3f886f443
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/fmt/mod.rs:1911:9
  44:     0x7ff284cf81ed - <rustc_middle[232bd29a687eeda3]::infer::canonical::Canonical<rustc_middle[232bd29a687eeda3]::ty::typeck_results::UserType> as core[3afeaedfb140cde7]::fmt::Debug>::fmt
  45:     0x7ff2859a66ff - core::fmt::rt::Argument::fmt::ha5dde4cb71578cc2
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/fmt/rt.rs:138:9
  46:     0x7ff2859a66ff - core::fmt::write::hb1413899fd777907
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/core/src/fmt/mod.rs:1094:21
  47:     0x7ff284e79100 - <std[53b54636b4f52653]::io::buffered::bufwriter::BufWriter<std[53b54636b4f52653]::fs::File> as std[53b54636b4f52653]::io::Write>::write_fmt
  48:     0x7ff284c8fd4b - rustc_middle[232bd29a687eeda3]::mir::pretty::write_user_type_annotations
  49:     0x7ff284e587ee - rustc_middle[232bd29a687eeda3]::mir::pretty::dump_matched_mir_node::<rustc_mir_transform[bd425728c1433367]::pass_manager::dump_mir_for_phase_change::{closure#0}>
  50:     0x7ff283840fc6 - rustc_mir_transform[bd425728c1433367]::mir_const
  51:     0x7ff28383e853 - rustc_query_system[8be5ea0cc4c28ea6]::query::plumbing::try_execute_query::<rustc_query_impl[94005537e54250be]::queries::mir_const, rustc_query_impl[94005537e54250be]::plumbing::QueryCtxt>
  52:     0x7ff28383e4f5 - rustc_query_impl[94005537e54250be]::get_query::mir_const
  53:     0x7ff2836541a1 - rustc_mir_transform[bd425728c1433367]::mir_promoted
  54:     0x7ff28318dbea - rustc_query_system[8be5ea0cc4c28ea6]::query::plumbing::try_execute_query::<rustc_query_impl[94005537e54250be]::queries::mir_promoted, rustc_query_impl[94005537e54250be]::plumbing::QueryCtxt>
  55:     0x7ff28318cf5c - rustc_borrowck[2561add2bcb16522]::mir_borrowck
  56:     0x7ff28318b748 - rustc_query_system[8be5ea0cc4c28ea6]::query::plumbing::try_execute_query::<rustc_query_impl[94005537e54250be]::queries::mir_borrowck, rustc_query_impl[94005537e54250be]::plumbing::QueryCtxt>
  57:     0x7ff283bef386 - rustc_data_structures[fba7df231146955e]::sync::par_for_each_in::<&[rustc_span[811089187935bcb6]::def_id::LocalDefId], <rustc_middle[232bd29a687eeda3]::hir::map::Map>::par_body_owners<rustc_interface[1005215f39c21569]::passes::analysis::{closure#1}::{closure#0}>::{closure#0}>
  58:     0x7ff283be9f80 - rustc_interface[1005215f39c21569]::passes::analysis
  59:     0x7ff283f2bd47 - rustc_query_system[8be5ea0cc4c28ea6]::query::plumbing::try_execute_query::<rustc_query_impl[94005537e54250be]::queries::analysis, rustc_query_impl[94005537e54250be]::plumbing::QueryCtxt>
  60:     0x7ff283f2ba63 - rustc_query_impl[94005537e54250be]::get_query::analysis
  61:     0x7ff2839ccbcf - <rustc_middle[232bd29a687eeda3]::ty::context::GlobalCtxt>::enter::<rustc_driver_impl[27c68de0ac55b06a]::run_compiler::{closure#1}::{closure#2}::{closure#4}, core[3afeaedfb140cde7]::result::Result<(), rustc_span[811089187935bcb6]::ErrorGuaranteed>>
  62:     0x7ff2839cbcaf - <rustc_interface[1005215f39c21569]::interface::Compiler>::enter::<rustc_driver_impl[27c68de0ac55b06a]::run_compiler::{closure#1}::{closure#2}, core[3afeaedfb140cde7]::result::Result<core[3afeaedfb140cde7]::option::Option<rustc_interface[1005215f39c21569]::queries::Linker>, rustc_span[811089187935bcb6]::ErrorGuaranteed>>
  63:     0x7ff2839c933b - std[53b54636b4f52653]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[1005215f39c21569]::util::run_in_thread_pool_with_globals<rustc_interface[1005215f39c21569]::interface::run_compiler<core[3afeaedfb140cde7]::result::Result<(), rustc_span[811089187935bcb6]::ErrorGuaranteed>, rustc_driver_impl[27c68de0ac55b06a]::run_compiler::{closure#1}>::{closure#0}, core[3afeaedfb140cde7]::result::Result<(), rustc_span[811089187935bcb6]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[3afeaedfb140cde7]::result::Result<(), rustc_span[811089187935bcb6]::ErrorGuaranteed>>
  64:     0x7ff284098f55 - <<std[53b54636b4f52653]::thread::Builder>::spawn_unchecked_<rustc_interface[1005215f39c21569]::util::run_in_thread_pool_with_globals<rustc_interface[1005215f39c21569]::interface::run_compiler<core[3afeaedfb140cde7]::result::Result<(), rustc_span[811089187935bcb6]::ErrorGuaranteed>, rustc_driver_impl[27c68de0ac55b06a]::run_compiler::{closure#1}>::{closure#0}, core[3afeaedfb140cde7]::result::Result<(), rustc_span[811089187935bcb6]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[3afeaedfb140cde7]::result::Result<(), rustc_span[811089187935bcb6]::ErrorGuaranteed>>::{closure#1} as core[3afeaedfb140cde7]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  65:     0x7ff2859539d5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h20fe0a24dda744f1
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/alloc/src/boxed.rs:1985:9
  66:     0x7ff2859539d5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hb11b4529d66356f4
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/alloc/src/boxed.rs:1985:9
  67:     0x7ff2859539d5 - std::sys::unix::thread::Thread::new::thread_start::h896be1b4ceadbc98
                               at /rustc/2f2c438dce75d8cc532c3baa849eeddc0901802c/library/std/src/sys/unix/thread.rs:108:17
  68:     0x7ff281465bb5 - <unknown>
  69:     0x7ff2814e7d90 - <unknown>
  70:                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 1.71.0-nightly (2f2c438dc 2023-05-08) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z dump-mir=all

query stack during panic:
#0 [mir_const] preparing `ret_ref_local` for borrow checking
#1 [mir_promoted] promoting constants in MIR for `ret_ref_local`
#2 [mir_borrowck] borrow-checking `ret_ref_local`
#3 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to previous error

[matthiaskrgr]

Regression in 7b55296
#105961
cc @fmease

[fmease]

Thanks :)

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