ICE: has escaping bound vars, so it cannot be wrapped in a dummy binder.

[matthiaskrgr]

Code

#![crate_type="lib"]

trait Foo<'x, T> {}

trait RefFoo<T> {
    fn ref_foo(&self) -> &'static T;
}

impl<T> RefFoo<T> for T where for<'a> &'a mut Vec<&'a u32>: Foo<'static, T> {
    fn ref_foo(&self) -> &'static T { todo!() }
}

fn coerce_lifetime2(iv: &i32) -> &i32 {
    <i32 as RefFoo<i32>>::ref_foo(unknown)
}

Meta

rustc --version --verbose:

rustc 1.73.0-nightly (0308df23e 2023-07-21)
binary: rustc
commit-hash: 0308df23e621e783e31a27ca5beaa01b9df60d4a
commit-date: 2023-07-21
host: x86_64-unknown-linux-gnu
release: 1.73.0-nightly
LLVM version: 16.0.5

Error output

error[E0425]: cannot find value `unknown` in this scope
  --> treereduce.out:14:35
   |
14 |     <i32 as RefFoo<i32>>::ref_foo(unknown)
   |                                   ^^^^^^^ not found in this scope

Backtrace

thread 'rustc' panicked at '`<std::vec::Vec<&'a u32> as std::ops::Deref>` has escaping bound vars, so it cannot be wrapped in a dummy binder.', compiler/rustc_hir_analysis/src/autoderef.rs:144:13
stack backtrace:
   0:     0x7f8d05162fc1 - std::backtrace_rs::backtrace::libunwind::trace::h8f154b6a796326e2
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7f8d05162fc1 - std::backtrace_rs::backtrace::trace_unsynchronized::hb8abeaf7dfb1c24b
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f8d05162fc1 - std::sys_common::backtrace::_print_fmt::h3f47e60290db41a5
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/sys_common/backtrace.rs:65:5
   3:     0x7f8d05162fc1 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h4552f2dd442a589d
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7f8d051c949c - core::fmt::rt::Argument::fmt::h78a6be6446bd82bd
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/core/src/fmt/rt.rs:138:9
   5:     0x7f8d051c949c - core::fmt::write::hd14ae211f7dd66b2
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/core/src/fmt/mod.rs:1094:21
   6:     0x7f8d051557ae - std::io::Write::write_fmt::hdc8c0b5c45666412
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/io/mod.rs:1714:15
   7:     0x7f8d05162dd5 - std::sys_common::backtrace::_print::h381fcf6b91d9d880
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7f8d05162dd5 - std::sys_common::backtrace::print::hcfe75c5be0f60777
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7f8d05165e2a - std::panicking::panic_hook_with_disk_dump::{{closure}}::hfe5fad22482c9f6d
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/panicking.rs:278:22
  10:     0x7f8d05165ac3 - std::panicking::panic_hook_with_disk_dump::hc822f132c197763d
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/panicking.rs:312:9
  11:     0x7f8d083928b9 - rustc_driver_impl[fead4037fc65a3e4]::install_ice_hook::{closure#0}
  12:     0x7f8d051666d0 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h549a9102e6ec42b3
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/alloc/src/boxed.rs:2021:9
  13:     0x7f8d051666d0 - std::panicking::rust_panic_with_hook::h8adf1e4a5b603f89
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/panicking.rs:733:13
  14:     0x7f8d05166457 - std::panicking::begin_panic_handler::{{closure}}::h2014913c812d3cf1
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/panicking.rs:621:13
  15:     0x7f8d05163426 - std::sys_common::backtrace::__rust_end_short_backtrace::h193583092ae14d92
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/sys_common/backtrace.rs:151:18
  16:     0x7f8d051661a2 - rust_begin_unwind
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/panicking.rs:617:5
  17:     0x7f8d051c5853 - core::panicking::panic_fmt::h8807fafd07400059
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/core/src/panicking.rs:67:14
  18:     0x7f8d06779571 - <rustc_hir_analysis[4792b5973f634bb5]::autoderef::Autoderef as core[d7f3879bb305828b]::iter::traits::iterator::Iterator>::next
  19:     0x7f8d0856cdb6 - <rustc_hir_typeck[8bbb5d1168ba11ff]::fn_ctxt::FnCtxt>::err_ctxt::{closure#1}
  20:     0x7f8d08f652c9 - <rustc_infer[741fbff21ee3a7cb]::infer::error_reporting::TypeErrCtxt as rustc_trait_selection[13d8f5ce54c19b1b]::traits::error_reporting::suggestions::TypeErrCtxtExt>::suggest_dereferences
  21:     0x7f8d08f7c81e - <rustc_infer[741fbff21ee3a7cb]::infer::error_reporting::TypeErrCtxt as rustc_trait_selection[13d8f5ce54c19b1b]::traits::error_reporting::TypeErrCtxtExt>::report_selection_error
  22:     0x7f8d08f86edb - <rustc_infer[741fbff21ee3a7cb]::infer::error_reporting::TypeErrCtxt as rustc_trait_selection[13d8f5ce54c19b1b]::traits::error_reporting::InferCtxtPrivExt>::report_fulfillment_error
  23:     0x7f8d08f79bab - <rustc_infer[741fbff21ee3a7cb]::infer::error_reporting::TypeErrCtxt as rustc_trait_selection[13d8f5ce54c19b1b]::traits::error_reporting::TypeErrCtxtExt>::report_fulfillment_errors
  24:     0x7f8d06744511 - <rustc_hir_typeck[8bbb5d1168ba11ff]::fn_ctxt::FnCtxt>::check_call
  25:     0x7f8d066a7788 - <rustc_hir_typeck[8bbb5d1168ba11ff]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
  26:     0x7f8d066f1463 - <rustc_hir_typeck[8bbb5d1168ba11ff]::fn_ctxt::FnCtxt>::check_block_with_expected
  27:     0x7f8d066a7d24 - <rustc_hir_typeck[8bbb5d1168ba11ff]::fn_ctxt::FnCtxt>::check_expr_with_expectation_and_args
  28:     0x7f8d06e6cfe6 - <rustc_hir_typeck[8bbb5d1168ba11ff]::fn_ctxt::FnCtxt>::check_return_expr
  29:     0x7f8d06e6392a - rustc_hir_typeck[8bbb5d1168ba11ff]::check::check_fn
  30:     0x7f8d06e521e9 - rustc_hir_typeck[8bbb5d1168ba11ff]::typeck
  31:     0x7f8d06451d3e - rustc_query_impl[89227dfa721c8c03]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[89227dfa721c8c03]::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle[2e38e64f479fe5b8]::query::erase::Erased<[u8; 8usize]>>
  32:     0x7f8d06451d0e - <rustc_query_impl[89227dfa721c8c03]::query_impl::typeck::dynamic_query::{closure#2} as core[d7f3879bb305828b]::ops::function::FnOnce<(rustc_middle[2e38e64f479fe5b8]::ty::context::TyCtxt, rustc_span[a321f1cb1523dd0b]::def_id::LocalDefId)>>::call_once
  33:     0x7f8d06570c9d - rustc_query_system[c0a52eceb1a71305]::query::plumbing::try_execute_query::<rustc_query_impl[89227dfa721c8c03]::DynamicConfig<rustc_query_system[c0a52eceb1a71305]::query::caches::VecCache<rustc_span[a321f1cb1523dd0b]::def_id::LocalDefId, rustc_middle[2e38e64f479fe5b8]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[89227dfa721c8c03]::plumbing::QueryCtxt, false>
  34:     0x7f8d07cfc9df - rustc_query_impl[89227dfa721c8c03]::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
  35:     0x7f8d0782ffad - rustc_data_structures[4d0670106038e5ac]::sync::par_for_each_in::<&[rustc_span[a321f1cb1523dd0b]::def_id::LocalDefId], <rustc_middle[2e38e64f479fe5b8]::hir::map::Map>::par_body_owners<rustc_hir_analysis[4792b5973f634bb5]::check_crate::{closure#7}>::{closure#0}>
  36:     0x7f8d0782f2ac - rustc_hir_analysis[4792b5973f634bb5]::check_crate
  37:     0x7f8d0782b4ba - rustc_interface[c9554cd0b74ea93d]::passes::analysis
  38:     0x7f8d0787c82a - rustc_query_impl[89227dfa721c8c03]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[89227dfa721c8c03]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[2e38e64f479fe5b8]::query::erase::Erased<[u8; 1usize]>>
  39:     0x7f8d0787c819 - <rustc_query_impl[89227dfa721c8c03]::query_impl::analysis::dynamic_query::{closure#2} as core[d7f3879bb305828b]::ops::function::FnOnce<(rustc_middle[2e38e64f479fe5b8]::ty::context::TyCtxt, ())>>::call_once
  40:     0x7f8d07a32088 - rustc_query_system[c0a52eceb1a71305]::query::plumbing::try_execute_query::<rustc_query_impl[89227dfa721c8c03]::DynamicConfig<rustc_query_system[c0a52eceb1a71305]::query::caches::SingleCache<rustc_middle[2e38e64f479fe5b8]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[89227dfa721c8c03]::plumbing::QueryCtxt, false>
  41:     0x7f8d07a31e17 - rustc_query_impl[89227dfa721c8c03]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  42:     0x7f8d075d3745 - <rustc_middle[2e38e64f479fe5b8]::ty::context::GlobalCtxt>::enter::<rustc_driver_impl[fead4037fc65a3e4]::run_compiler::{closure#1}::{closure#2}::{closure#4}, core[d7f3879bb305828b]::result::Result<(), rustc_span[a321f1cb1523dd0b]::ErrorGuaranteed>>
  43:     0x7f8d075d2d72 - <rustc_interface[c9554cd0b74ea93d]::interface::Compiler>::enter::<rustc_driver_impl[fead4037fc65a3e4]::run_compiler::{closure#1}::{closure#2}, core[d7f3879bb305828b]::result::Result<core[d7f3879bb305828b]::option::Option<rustc_interface[c9554cd0b74ea93d]::queries::Linker>, rustc_span[a321f1cb1523dd0b]::ErrorGuaranteed>>
  44:     0x7f8d075cff64 - std[bbbc53192af03470]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[c9554cd0b74ea93d]::util::run_in_thread_pool_with_globals<rustc_interface[c9554cd0b74ea93d]::interface::run_compiler<core[d7f3879bb305828b]::result::Result<(), rustc_span[a321f1cb1523dd0b]::ErrorGuaranteed>, rustc_driver_impl[fead4037fc65a3e4]::run_compiler::{closure#1}>::{closure#0}, core[d7f3879bb305828b]::result::Result<(), rustc_span[a321f1cb1523dd0b]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[d7f3879bb305828b]::result::Result<(), rustc_span[a321f1cb1523dd0b]::ErrorGuaranteed>>
  45:     0x7f8d075cf68e - <<std[bbbc53192af03470]::thread::Builder>::spawn_unchecked_<rustc_interface[c9554cd0b74ea93d]::util::run_in_thread_pool_with_globals<rustc_interface[c9554cd0b74ea93d]::interface::run_compiler<core[d7f3879bb305828b]::result::Result<(), rustc_span[a321f1cb1523dd0b]::ErrorGuaranteed>, rustc_driver_impl[fead4037fc65a3e4]::run_compiler::{closure#1}>::{closure#0}, core[d7f3879bb305828b]::result::Result<(), rustc_span[a321f1cb1523dd0b]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[d7f3879bb305828b]::result::Result<(), rustc_span[a321f1cb1523dd0b]::ErrorGuaranteed>>::{closure#1} as core[d7f3879bb305828b]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  46:     0x7f8d05170dc5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h5a713c95dff49eb9
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/alloc/src/boxed.rs:2007:9
  47:     0x7f8d05170dc5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h6c2630f276b49e94
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/alloc/src/boxed.rs:2007:9
  48:     0x7f8d05170dc5 - std::sys::unix::thread::Thread::new::thread_start::he7c79aaf88d71e7c
                               at /rustc/0308df23e621e783e31a27ca5beaa01b9df60d4a/library/std/src/sys/unix/thread.rs:108:17
  49:     0x7f8d04f0244b - <unknown>
  50:     0x7f8d04f85e40 - <unknown>
  51:                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: please attach the file at `/tmp/im/rustc-ice-2023-07-22T08:46:18.205253213Z-3907939.txt` to your bug report

query stack during panic:
#0 [typeck] type-checking `coerce_lifetime2`
#1 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to previous error

For more information about this error, try `rustc --explain E0425`.

[matthiaskrgr]

Started crashing with 1.63.0

Regression in nightly-2022-05-19

commit[0] 2022-05-17: Auto merge of #92570 - jsha:rustdoc-search-refactor, r=GuillaumeGomez
commit[1] 2022-05-18: Auto merge of #97126 - JohnTitor:rollup-7gdt2aw, r=JohnTitor
commit[2] 2022-05-18: Auto merge of #97135 - Dylan-DPC:rollup-06u9pqn, r=Dylan-DPC
commit[3] 2022-05-18: Auto merge of #97110 - Kobzol:pgo-pid-in-profile, r=lqd
commit[4] 2022-05-18: Auto merge of #96867 - michaelwoerister:path-prefix-fixes-2, r=davidtwco
commit[5] 2022-05-18: Auto merge of #96800 - nbdd0121:const, r=nagisa
commit[6] 2022-05-18: Auto merge of #96863 - SparrowLii:let, r=michaelwoerister
commit[7] 2022-05-18: Auto merge of #97019 - b-naber:transition-to-valtrees-pt1, r=oli-obk

[apiraino]

WG-prioritization assigning priority (Zulip discussion).

@rustbot label -I-prioritize +P-medium -needs-triage