ICE: let_else with -Zunpretty=hir, let-else-binding-immutable.r, None in compiler/rustc_ast_pretty/src/pp.rs

[matthiaskrgr]

./src/test/ui/let-else/let-else-binding-immutable.rs

Code

// from rfc2005 test suite

#![feature(let_else)]

pub fn main() {
    let Some(x) = &Some(3) else {
        panic!();
    };
    *x += 1; //~ ERROR: cannot assign to `*x`, which is behind a `&` reference
}

Meta

rustc --version --verbose:

rustc 1.64.0-nightly (87588a2af 2022-07-13)
binary: rustc
commit-hash: 87588a2afd9ca903366f0deaf84d805f34469384
commit-date: 2022-07-13
host: x86_64-unknown-linux-gnu
release: 1.64.0-nightly
LLVM version: 14.0.6

Error output

rustc ./src/test/ui/let-else/let-else-binding-immutable.rs -Zunpretty=hir

Backtrace

thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', compiler/rustc_ast_pretty/src/pp.rs:412:52
stack backtrace:
   0:     0x7fe2d78a2850 - std::backtrace_rs::backtrace::libunwind::trace::h546e34b136647819
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   1:     0x7fe2d78a2850 - std::backtrace_rs::backtrace::trace_unsynchronized::h76e576fe0a1ec65e
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7fe2d78a2850 - std::sys_common::backtrace::_print_fmt::h3489fbb9d5d01094
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/sys_common/backtrace.rs:66:5
   3:     0x7fe2d78a2850 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h401cfc97a3c2f247
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/sys_common/backtrace.rs:45:22
   4:     0x7fe2d78fbe2c - core::fmt::write::h327c921ac5532dc9
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/core/src/fmt/mod.rs:1198:17
   5:     0x7fe2d7893e15 - std::io::Write::write_fmt::h334c1fe5d85b41a9
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/io/mod.rs:1672:15
   6:     0x7fe2d78a54e1 - std::sys_common::backtrace::_print::hddc5656bc817cc55
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/sys_common/backtrace.rs:48:5
   7:     0x7fe2d78a54e1 - std::sys_common::backtrace::print::h46adcb0dcb6fbe81
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/sys_common/backtrace.rs:35:9
   8:     0x7fe2d78a54e1 - std::panicking::default_hook::{{closure}}::h7e55301ce91fa17d
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/panicking.rs:295:22
   9:     0x7fe2d78a51b3 - std::panicking::default_hook::he24b412fa8dea167
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/panicking.rs:314:9
  10:     0x7fe2d8147e04 - rustc_driver[24990f24c5f9557a]::DEFAULT_HOOK::{closure#0}::{closure#0}
  11:     0x7fe2d78a5cb6 - std::panicking::rust_panic_with_hook::hd6be56b55800f278
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/panicking.rs:702:17
  12:     0x7fe2d78a5ac9 - std::panicking::begin_panic_handler::{{closure}}::h299e1cde9b2d55bf
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/panicking.rs:586:13
  13:     0x7fe2d78a2d34 - std::sys_common::backtrace::__rust_end_short_backtrace::h217affeadc688779
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/sys_common/backtrace.rs:138:18
  14:     0x7fe2d78a5832 - rust_begin_unwind
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/panicking.rs:584:5
  15:     0x7fe2d7869b73 - core::panicking::panic_fmt::hce80afc1c6c77893
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/core/src/panicking.rs:142:14
  16:     0x7fe2d7869a3d - core::panicking::panic::h3f12aada7d8b1473
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/core/src/panicking.rs:48:5
  17:     0x7fe2da289fcf - <rustc_ast_pretty[c2f1cb48f89c6c8]::pp::Printer>::eof
  18:     0x7fe2d8e5005c - rustc_hir_pretty[ace3b7ae5e9072c9]::print_crate
  19:     0x7fe2d8139ba3 - rustc_driver[24990f24c5f9557a]::pretty::print_after_hir_lowering::{closure#1}
  20:     0x7fe2d81397bc - rustc_driver[24990f24c5f9557a]::pretty::print_after_hir_lowering
  21:     0x7fe2d81223ba - <rustc_interface[d9e16a24b5464548]::passes::QueryContext>::enter::<rustc_driver[24990f24c5f9557a]::run_compiler::{closure#1}::{closure#2}::{closure#1}, core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>>
  22:     0x7fe2da2ea90f - <rustc_interface[d9e16a24b5464548]::interface::Compiler>::enter::<rustc_driver[24990f24c5f9557a]::run_compiler::{closure#1}::{closure#2}, core[734affb1a3eaf053]::result::Result<core[734affb1a3eaf053]::option::Option<rustc_interface[d9e16a24b5464548]::queries::Linker>, rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>>
  23:     0x7fe2da2e676f - rustc_span[b8cb56592c4d9b67]::with_source_map::<core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>, rustc_interface[d9e16a24b5464548]::interface::create_compiler_and_run<core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>, rustc_driver[24990f24c5f9557a]::run_compiler::{closure#1}>::{closure#1}>
  24:     0x7fe2da302880 - rustc_interface[d9e16a24b5464548]::interface::create_compiler_and_run::<core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>, rustc_driver[24990f24c5f9557a]::run_compiler::{closure#1}>
  25:     0x7fe2da316a02 - <scoped_tls[93927b52d599628f]::ScopedKey<rustc_span[b8cb56592c4d9b67]::SessionGlobals>>::set::<rustc_interface[d9e16a24b5464548]::interface::run_compiler<core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>, rustc_driver[24990f24c5f9557a]::run_compiler::{closure#1}>::{closure#0}, core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>>
  26:     0x7fe2da2e8cff - std[66dc708de7974585]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[d9e16a24b5464548]::util::run_in_thread_pool_with_globals<rustc_interface[d9e16a24b5464548]::interface::run_compiler<core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>, rustc_driver[24990f24c5f9557a]::run_compiler::{closure#1}>::{closure#0}, core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>>::{closure#0}, core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>>
  27:     0x7fe2da302cd9 - <<std[66dc708de7974585]::thread::Builder>::spawn_unchecked_<rustc_interface[d9e16a24b5464548]::util::run_in_thread_pool_with_globals<rustc_interface[d9e16a24b5464548]::interface::run_compiler<core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>, rustc_driver[24990f24c5f9557a]::run_compiler::{closure#1}>::{closure#0}, core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>>::{closure#0}, core[734affb1a3eaf053]::result::Result<(), rustc_errors[7a9b9cc96f052d83]::ErrorGuaranteed>>::{closure#1} as core[734affb1a3eaf053]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  28:     0x7fe2d78af703 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h332a3f23c5b3d8bc
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/alloc/src/boxed.rs:1934:9
  29:     0x7fe2d78af703 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h33b3da7f4496df00
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/alloc/src/boxed.rs:1934:9
  30:     0x7fe2d78af703 - std::sys::unix::thread::Thread::new::thread_start::hf48274d01b2ded65
                               at /rustc/87588a2afd9ca903366f0deaf84d805f34469384/library/std/src/sys/unix/thread.rs:108:17
  31:     0x7fe2d768054d - <unknown>
  32:     0x7fe2d7705874 - clone
  33:                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 1.64.0-nightly (87588a2af 2022-07-13) running on x86_64-unknown-linux-gnu

note: compiler flags: -Z unpretty=hir

query stack during panic:
end of query stack