ICE: `let_else` ices when placed in a const _: () = { ... }

[tuxmark5]

Code

Link to playground

#![feature(let_else)]

const _: () = {
    fn foo(x: Option<u32>) { 
        let Some(_) = x else { panic!() };
    }
};

Meta

rustc --version --verbose:

rustc 1.65.0-nightly (d394408fb 2022-08-07)
binary: rustc
commit-hash: d394408fb38c4de61f765a3ed5189d2731a1da91
commit-date: 2022-08-07
host: x86_64-unknown-linux-gnu
release: 1.65.0-nightly
LLVM version: 14.0.6

Error output

thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', compiler/rustc_ast_pretty/src/pp.rs:412:52

Backtrace

Compiling playground v0.0.1 (/playground)
thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', compiler/rustc_ast_pretty/src/pp.rs:412:52
stack backtrace:
   0:     0x7f5b91273c60 - std::backtrace_rs::backtrace::libunwind::trace::he9fb4f8b6a719925
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   1:     0x7f5b91273c60 - std::backtrace_rs::backtrace::trace_unsynchronized::h9b7fbe883834f3d3
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f5b91273c60 - std::sys_common::backtrace::_print_fmt::he6dc464748e1c2a6
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/sys_common/backtrace.rs:66:5
   3:     0x7f5b91273c60 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hbbebb5a127178bd8
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/sys_common/backtrace.rs:45:22
   4:     0x7f5b912cf62c - core::fmt::write::h0cbbad9957d29634
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/core/src/fmt/mod.rs:1198:17
   5:     0x7f5b91264ca5 - std::io::Write::write_fmt::h7bfbf18cf3112e27
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/io/mod.rs:1672:15
   6:     0x7f5b91276941 - std::sys_common::backtrace::_print::h00538e56e1e7f9f3
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/sys_common/backtrace.rs:48:5
   7:     0x7f5b91276941 - std::sys_common::backtrace::print::h5045ae575039f7dc
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/sys_common/backtrace.rs:35:9
   8:     0x7f5b91276941 - std::panicking::default_hook::{{closure}}::hb244797a8318c775
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/panicking.rs:295:22
   9:     0x7f5b9127660e - std::panicking::default_hook::hf1c8bb50e38d503a
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/panicking.rs:314:9
  10:     0x7f5b93afde54 - <rustc_driver[a8b7cf0aaae3bece]::DEFAULT_HOOK::{closure#0}::{closure#0} as core[14a5817fc6fced97]::ops::function::FnOnce<(&core[14a5817fc6fced97]::panic::panic_info::PanicInfo,)>>::call_once::{shim:vtable#0}
  11:     0x7f5b91277176 - std::panicking::rust_panic_with_hook::h1e44cac8640df897
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/panicking.rs:702:17
  12:     0x7f5b91276f89 - std::panicking::begin_panic_handler::{{closure}}::h5846a4a3859a5834
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/panicking.rs:586:13
  13:     0x7f5b91274184 - std::sys_common::backtrace::__rust_end_short_backtrace::hb9460bca71f51584
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/sys_common/backtrace.rs:138:18
  14:     0x7f5b91276cf2 - rust_begin_unwind
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/panicking.rs:584:5
  15:     0x7f5b912cc103 - core::panicking::panic_fmt::h218ea2f8c3932e1a
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/core/src/panicking.rs:142:14
  16:     0x7f5b912cbf4d - core::panicking::panic::h9f951b05a104beec
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/core/src/panicking.rs:48:5
  17:     0x7f5b92f4db48 - <rustc_ast_pretty[9702ff83c931f4ee]::pp::Printer>::eof
  18:     0x7f5b933afb06 - rustc_hir_pretty[73b8d10daec5c303]::to_string::<<rustc_metadata[841ddd31d681d6d0]::rmeta::encoder::EncodeContext>::encode_rendered_const_for_body::{closure#0}>
  19:     0x7f5b933a5433 - <rustc_metadata[841ddd31d681d6d0]::rmeta::encoder::EncodeContext as rustc_hir[8d56236dc9dc55b]::intravisit::Visitor>::visit_item
  20:     0x7f5b933a307c - <rustc_middle[eac570560e79f144]::hir::map::Map>::visit_all_item_likes_in_crate::<rustc_metadata[841ddd31d681d6d0]::rmeta::encoder::EncodeContext>
  21:     0x7f5b9338f316 - <rustc_metadata[841ddd31d681d6d0]::rmeta::encoder::EncodeContext>::encode_crate_root
  22:     0x7f5b9330c482 - rustc_metadata[841ddd31d681d6d0]::rmeta::encoder::encode_metadata_impl
  23:     0x7f5b932f21de - rustc_data_structures[13739aee9e3adeb3]::sync::join::<rustc_metadata[841ddd31d681d6d0]::rmeta::encoder::encode_metadata::{closure#0}, rustc_metadata[841ddd31d681d6d0]::rmeta::encoder::encode_metadata::{closure#1}, (), ()>
  24:     0x7f5b932f20b9 - rustc_metadata[841ddd31d681d6d0]::rmeta::encoder::encode_metadata
  25:     0x7f5b932f12a0 - rustc_metadata[841ddd31d681d6d0]::fs::encode_and_write_metadata
  26:     0x7f5b932eb73f - <rustc_interface[8fcbc5e5f8656a70]::passes::QueryContext>::enter::<<rustc_interface[8fcbc5e5f8656a70]::queries::Queries>::ongoing_codegen::{closure#0}::{closure#0}, core[14a5817fc6fced97]::result::Result<alloc[276615df98e61306]::boxed::Box<dyn core[14a5817fc6fced97]::any::Any>, rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>>
  27:     0x7f5b932e3b93 - <rustc_interface[8fcbc5e5f8656a70]::queries::Queries>::ongoing_codegen
  28:     0x7f5b932e2923 - <rustc_interface[8fcbc5e5f8656a70]::interface::Compiler>::enter::<rustc_driver[a8b7cf0aaae3bece]::run_compiler::{closure#1}::{closure#2}, core[14a5817fc6fced97]::result::Result<core[14a5817fc6fced97]::option::Option<rustc_interface[8fcbc5e5f8656a70]::queries::Linker>, rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>>
  29:     0x7f5b932d62ca - rustc_span[1d346f2d776e330f]::with_source_map::<core[14a5817fc6fced97]::result::Result<(), rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>, rustc_interface[8fcbc5e5f8656a70]::interface::create_compiler_and_run<core[14a5817fc6fced97]::result::Result<(), rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>, rustc_driver[a8b7cf0aaae3bece]::run_compiler::{closure#1}>::{closure#1}>
  30:     0x7f5b932d5ca0 - rustc_interface[8fcbc5e5f8656a70]::interface::create_compiler_and_run::<core[14a5817fc6fced97]::result::Result<(), rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>, rustc_driver[a8b7cf0aaae3bece]::run_compiler::{closure#1}>
  31:     0x7f5b932d4011 - <scoped_tls[72dc8926b5a0bddb]::ScopedKey<rustc_span[1d346f2d776e330f]::SessionGlobals>>::set::<rustc_interface[8fcbc5e5f8656a70]::interface::run_compiler<core[14a5817fc6fced97]::result::Result<(), rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>, rustc_driver[a8b7cf0aaae3bece]::run_compiler::{closure#1}>::{closure#0}, core[14a5817fc6fced97]::result::Result<(), rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>>
  32:     0x7f5b932d3cff - std[5f292d4f9c23a90f]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[8fcbc5e5f8656a70]::util::run_in_thread_pool_with_globals<rustc_interface[8fcbc5e5f8656a70]::interface::run_compiler<core[14a5817fc6fced97]::result::Result<(), rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>, rustc_driver[a8b7cf0aaae3bece]::run_compiler::{closure#1}>::{closure#0}, core[14a5817fc6fced97]::result::Result<(), rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>>::{closure#0}, core[14a5817fc6fced97]::result::Result<(), rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>>
  33:     0x7f5b93928079 - <<std[5f292d4f9c23a90f]::thread::Builder>::spawn_unchecked_<rustc_interface[8fcbc5e5f8656a70]::util::run_in_thread_pool_with_globals<rustc_interface[8fcbc5e5f8656a70]::interface::run_compiler<core[14a5817fc6fced97]::result::Result<(), rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>, rustc_driver[a8b7cf0aaae3bece]::run_compiler::{closure#1}>::{closure#0}, core[14a5817fc6fced97]::result::Result<(), rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>>::{closure#0}, core[14a5817fc6fced97]::result::Result<(), rustc_errors[1e52fd968b2fd3e0]::ErrorGuaranteed>>::{closure#1} as core[14a5817fc6fced97]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  34:     0x7f5b91281143 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h2d81a5fef99140ee
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/alloc/src/boxed.rs:1935:9
  35:     0x7f5b91281143 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h1499905d273c8ff9
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/alloc/src/boxed.rs:1935:9
  36:     0x7f5b91281143 - std::sys::unix::thread::Thread::new::thread_start::hd9acf2283a0a68a9
                               at /rustc/34a6cae28e7013ff0e640026a8e46f315426829d/library/std/src/sys/unix/thread.rs:108:17
  37:     0x7f5b91153609 - start_thread
  38:     0x7f5b91076133 - clone
  39:                0x0 - <unknown>

error: internal compiler error: unexpected panic

note: 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: rustc 1.65.0-nightly (34a6cae28 2022-08-09) running on x86_64-unknown-linux-gnu

note: compiler flags: --crate-type lib -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
error: could not compile `playground`

[Noratrieb]

searched nightlies: from nightly-2022-01-01 to nightly-2022-08-08
regressed nightly: nightly-2022-07-14
searched commit range: 1c7b36d...87588a2
regressed commit: c80dde4

bisected with cargo-bisect-rustc v0.6.4

Host triple: aarch64-apple-darwin
Reproduce with:

cargo bisect-rustc 2022-01-01 --end 2022-08-08 -- check

[Noratrieb]

It was probably regressed by #98574, cc @dingxiangfei2009

[est31]

@rustbot label F-let-else