ICE: attrs: None at diagnostics.rs:804:30

[matthiaskrgr]

Code

fn bar() -> String {
    #[cfg(feature = )]
    [1, 2, 3].iter().map().collect::<String>()
    #[attr]
    String::new()
}

Meta

rustc --version --verbose:

rustc 1.76.0-nightly (0919ad183 2023-12-02)
binary: rustc
commit-hash: 0919ad18381f6f4fcaddc809e786553e028bbde0
commit-date: 2023-12-02
host: x86_64-unknown-linux-gnu
release: 1.76.0-nightly
LLVM version: 17.0.5

Error output

<output>

Backtrace

thread 'rustc' panicked at compiler/rustc_parse/src/parser/diagnostics.rs:804:30:
called `Option::unwrap()` on a `None` value
stack backtrace:
   0:     0x7f0bf658b28c - std::backtrace_rs::backtrace::libunwind::trace::hf60fec8ebc0c5e46
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5
   1:     0x7f0bf658b28c - std::backtrace_rs::backtrace::trace_unsynchronized::h6b0117997e292206
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f0bf658b28c - std::sys_common::backtrace::_print_fmt::h44b32f67603b518c
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/sys_common/backtrace.rs:68:5
   3:     0x7f0bf658b28c - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h27fb11da10f33041
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7f0bf65de2c0 - core::fmt::rt::Argument::fmt::h3fc263cbfb58e262
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/core/src/fmt/rt.rs:142:9
   5:     0x7f0bf65de2c0 - core::fmt::write::h02278e02d2d5f049
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/core/src/fmt/mod.rs:1120:17
   6:     0x7f0bf657f17f - std::io::Write::write_fmt::hffc80e01f3ab27bb
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/io/mod.rs:1810:15
   7:     0x7f0bf658b074 - std::sys_common::backtrace::_print::h2544e68645d26127
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7f0bf658b074 - std::sys_common::backtrace::print::h2e0aa5ce667bab38
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7f0bf658dd07 - std::panicking::default_hook::{{closure}}::h0a15ec650eef3042
  10:     0x7f0bf658da6f - std::panicking::default_hook::heb7c98638cae941f
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/panicking.rs:292:9
  11:     0x7f0bf92f1e80 - std[87e1f5a9db75d886]::panicking::update_hook::<alloc[3858379072058137]::boxed::Box<rustc_driver_impl[cfa48c30a51debc9]::install_ice_hook::{closure#0}>>::{closure#0}
  12:     0x7f0bf658e448 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::hdf7e5e901896fee8
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/alloc/src/boxed.rs:2021:9
  13:     0x7f0bf658e448 - std::panicking::rust_panic_with_hook::h5b2da380fe2b9567
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/panicking.rs:783:13
  14:     0x7f0bf658e169 - std::panicking::begin_panic_handler::{{closure}}::h3f96784bf0ca7405
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/panicking.rs:649:13
  15:     0x7f0bf658b756 - std::sys_common::backtrace::__rust_end_short_backtrace::hf79e6243acc919d5
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/sys_common/backtrace.rs:171:18
  16:     0x7f0bf658df02 - rust_begin_unwind
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/panicking.rs:645:5
  17:     0x7f0bf65da995 - core::panicking::panic_fmt::h30900c9a84f4042b
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/core/src/panicking.rs:72:14
  18:     0x7f0bf65daa43 - core::panicking::panic::h234da1d28a5ceaa3
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/core/src/panicking.rs:142:5
  19:     0x7f0bf8015d98 - <rustc_parse[af32aa468c2a8517]::parser::Parser>::attr_on_non_tail_expr
  20:     0x7f0bfad098b0 - <rustc_parse[af32aa468c2a8517]::parser::Parser>::parse_block_tail
  21:     0x7f0bfa9da5a2 - <rustc_parse[af32aa468c2a8517]::parser::Parser>::parse_fn
  22:     0x7f0bfacf77ef - <rustc_parse[af32aa468c2a8517]::parser::Parser>::parse_item_kind
  23:     0x7f0bfa9f293f - <rustc_parse[af32aa468c2a8517]::parser::Parser>::parse_item_common
  24:     0x7f0bfa9effec - <rustc_parse[af32aa468c2a8517]::parser::Parser>::parse_mod
  25:     0x7f0bfb58b490 - rustc_interface[940fd56aa190939d]::passes::parse
  26:     0x7f0bfb58b20e - <rustc_interface[940fd56aa190939d]::queries::Queries>::parse
  27:     0x7f0bfb581f25 - rustc_interface[940fd56aa190939d]::interface::run_compiler::<core[75c7cbfbe7f98c9f]::result::Result<(), rustc_span[63578016ae5b5f6e]::ErrorGuaranteed>, rustc_driver_impl[cfa48c30a51debc9]::run_compiler::{closure#0}>::{closure#0}
  28:     0x7f0bfb575549 - std[87e1f5a9db75d886]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[940fd56aa190939d]::util::run_in_thread_with_globals<rustc_interface[940fd56aa190939d]::util::run_in_thread_pool_with_globals<rustc_interface[940fd56aa190939d]::interface::run_compiler<core[75c7cbfbe7f98c9f]::result::Result<(), rustc_span[63578016ae5b5f6e]::ErrorGuaranteed>, rustc_driver_impl[cfa48c30a51debc9]::run_compiler::{closure#0}>::{closure#0}, core[75c7cbfbe7f98c9f]::result::Result<(), rustc_span[63578016ae5b5f6e]::ErrorGuaranteed>>::{closure#0}, core[75c7cbfbe7f98c9f]::result::Result<(), rustc_span[63578016ae5b5f6e]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[75c7cbfbe7f98c9f]::result::Result<(), rustc_span[63578016ae5b5f6e]::ErrorGuaranteed>>
  29:     0x7f0bfb575373 - <<std[87e1f5a9db75d886]::thread::Builder>::spawn_unchecked_<rustc_interface[940fd56aa190939d]::util::run_in_thread_with_globals<rustc_interface[940fd56aa190939d]::util::run_in_thread_pool_with_globals<rustc_interface[940fd56aa190939d]::interface::run_compiler<core[75c7cbfbe7f98c9f]::result::Result<(), rustc_span[63578016ae5b5f6e]::ErrorGuaranteed>, rustc_driver_impl[cfa48c30a51debc9]::run_compiler::{closure#0}>::{closure#0}, core[75c7cbfbe7f98c9f]::result::Result<(), rustc_span[63578016ae5b5f6e]::ErrorGuaranteed>>::{closure#0}, core[75c7cbfbe7f98c9f]::result::Result<(), rustc_span[63578016ae5b5f6e]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[75c7cbfbe7f98c9f]::result::Result<(), rustc_span[63578016ae5b5f6e]::ErrorGuaranteed>>::{closure#1} as core[75c7cbfbe7f98c9f]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  30:     0x7f0bf65982d5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h7c5f0316c4d081e7
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/alloc/src/boxed.rs:2007:9
  31:     0x7f0bf65982d5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::ha58713453cbc0382
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/alloc/src/boxed.rs:2007:9
  32:     0x7f0bf65982d5 - std::sys::unix::thread::Thread::new::thread_start::h8f26f58dd762698d
                               at /rustc/0919ad18381f6f4fcaddc809e786553e028bbde0/library/std/src/sys/unix/thread.rs:108:17
  33:     0x7f0bf63889eb - <unknown>
  34:     0x7f0bf640c7cc - <unknown>
  35:                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-2023-12-02T11_40_29-2632871.txt` to your bug report

query stack during panic:
end of query stack

[eggyal]

searched nightlies: from nightly-2023-10-01 to nightly-2023-12-02
regressed nightly: nightly-2023-11-21
searched commit range: 9a66e44...3a85a5c
regressed commit: 46ecc10

bisected with cargo-bisect-rustc v0.6.7

Host triple: aarch64-unknown-linux-gnu
Reproduce with:

cargo bisect-rustc --start=2023-10-01 --end=2023-12-02 --regress=ice 

#117988 looks most likely responsible, cc @estebank