ICE: `range start index 2 out of range for slice of length 1`

[matthiaskrgr]

snippet:

fn serial_init() {
    lolunknown(COM_LCR_WLEN8 & (*"Sized".to_string().into_boxed_str()));
}

Version information

rustc 1.77.0-nightly (ca9ff83f1 2023-12-27)
binary: rustc
commit-hash: ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e
commit-date: 2023-12-27
host: x86_64-unknown-linux-gnu
release: 1.77.0-nightly
LLVM version: 17.0.6

Command:
/home/matthias/.rustup/toolchains/master/bin/rustc

Program output

error[E0425]: cannot find value `COM_LCR_WLEN8` in this scope
 --> /tmp/icemaker_global_tempdir.7uNXIvlaAV6Z/rustc_testrunner_tmpdir_reporting.Str0Z6Gmtz0Q/mvce.rs:2:16
  |
2 |     lolunknown(COM_LCR_WLEN8 & (*"Sized".to_string().into_boxed_str()));
  |                ^^^^^^^^^^^^^ not found in this scope

error[E0601]: `main` function not found in crate `mvce`
 --> /tmp/icemaker_global_tempdir.7uNXIvlaAV6Z/rustc_testrunner_tmpdir_reporting.Str0Z6Gmtz0Q/mvce.rs:3:2
  |
3 | }
  |  ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.7uNXIvlaAV6Z/rustc_testrunner_tmpdir_reporting.Str0Z6Gmtz0Q/mvce.rs`

error[E0425]: cannot find function `lolunknown` in this scope
 --> /tmp/icemaker_global_tempdir.7uNXIvlaAV6Z/rustc_testrunner_tmpdir_reporting.Str0Z6Gmtz0Q/mvce.rs:2:5
  |
2 |     lolunknown(COM_LCR_WLEN8 & (*"Sized".to_string().into_boxed_str()));
  |     ^^^^^^^^^^ not found in this scope

thread 'rustc' panicked at compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs:895:93:
range start index 2 out of range for slice of length 1
stack backtrace:
   0:     0x7fb547be9756 - std::backtrace_rs::backtrace::libunwind::trace::he999339051b091b1
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5
   1:     0x7fb547be9756 - std::backtrace_rs::backtrace::trace_unsynchronized::h9f78cacd86ef3c7d
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7fb547be9756 - std::sys_common::backtrace::_print_fmt::h5c2049bdc1f08508
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/sys_common/backtrace.rs:68:5
   3:     0x7fb547be9756 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hdd02066d05dd488e
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7fb547c3c080 - core::fmt::rt::Argument::fmt::h07dee6933df37465
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/core/src/fmt/rt.rs:142:9
   5:     0x7fb547c3c080 - core::fmt::write::ha16d8ae3c0bc27dc
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/core/src/fmt/mod.rs:1120:17
   6:     0x7fb547bdd40f - std::io::Write::write_fmt::h324b94efcec0fb0f
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/io/mod.rs:1810:15
   7:     0x7fb547be9534 - std::sys_common::backtrace::_print::h180e4cd35bfe4d65
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7fb547be9534 - std::sys_common::backtrace::print::h11fb4e42bbc715d4
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7fb547bec2c7 - std::panicking::default_hook::{{closure}}::h80aaed4cbdabb91a
  10:     0x7fb547bec029 - std::panicking::default_hook::h502b9a16d472ee07
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/panicking.rs:292:9
  11:     0x7fb544950cfc - std[855c18717e34e1aa]::panicking::update_hook::<alloc[c9845d7f62b03ea1]::boxed::Box<rustc_driver_impl[8fbc4de111867a14]::install_ice_hook::{closure#0}>>::{closure#0}
  12:     0x7fb547beca16 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h3aa4b4d4e29eab1e
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/alloc/src/boxed.rs:2029:9
  13:     0x7fb547beca16 - std::panicking::rust_panic_with_hook::hbddb29b82c27d8de
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/panicking.rs:783:13
  14:     0x7fb547bec762 - std::panicking::begin_panic_handler::{{closure}}::he139ae91aec90704
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/panicking.rs:657:13
  15:     0x7fb547be9c56 - std::sys_common::backtrace::__rust_end_short_backtrace::h3623a41a8c78295c
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/sys_common/backtrace.rs:171:18
  16:     0x7fb547bec4c0 - rust_begin_unwind
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/panicking.rs:645:5
  17:     0x7fb547c38785 - core::panicking::panic_fmt::hb165c617d5590abc
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/core/src/panicking.rs:72:14
  18:     0x7fb547c3e992 - core::slice::index::slice_start_index_len_fail_rt::h4ea466071628761d
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/core/src/slice/index.rs:52:5
  19:     0x7fb547c3e992 - core::slice::index::slice_start_index_len_fail::h35439c30e726957c
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/core/src/slice/index.rs:40:9
  20:     0x7fb54545e62c - <rustc_infer[f6bc2f3403a9f908]::infer::error_reporting::TypeErrCtxt as rustc_trait_selection[f0efaf6ce0ee3458]::traits::error_reporting::suggestions::TypeErrCtxtExt>::suggest_dereferences
  21:     0x7fb54547fffd - <rustc_infer[f6bc2f3403a9f908]::infer::error_reporting::TypeErrCtxt as rustc_trait_selection[f0efaf6ce0ee3458]::traits::error_reporting::type_err_ctxt_ext::TypeErrCtxtExt>::report_selection_error
  22:     0x7fb5454a76e1 - <rustc_infer[f6bc2f3403a9f908]::infer::error_reporting::TypeErrCtxt as rustc_trait_selection[f0efaf6ce0ee3458]::traits::error_reporting::type_err_ctxt_ext::InferCtxtPrivExt>::report_fulfillment_error
  23:     0x7fb54547b877 - <rustc_infer[f6bc2f3403a9f908]::infer::error_reporting::TypeErrCtxt as rustc_trait_selection[f0efaf6ce0ee3458]::traits::error_reporting::type_err_ctxt_ext::TypeErrCtxtExt>::report_fulfillment_errors
  24:     0x7fb54660aac1 - <rustc_hir_typeck[27e83c694fc7bb73]::fn_ctxt::FnCtxt>::type_inference_fallback
  25:     0x7fb545efe3ca - rustc_hir_typeck[27e83c694fc7bb73]::typeck
  26:     0x7fb545efd735 - rustc_query_impl[52c3636fd1c621b8]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[52c3636fd1c621b8]::query_impl::typeck::dynamic_query::{closure#2}::{closure#0}, rustc_middle[eadc16aa5b2d798c]::query::erase::Erased<[u8; 8usize]>>
  27:     0x7fb545e16003 - rustc_query_system[6816ad35e73f53f7]::query::plumbing::try_execute_query::<rustc_query_impl[52c3636fd1c621b8]::DynamicConfig<rustc_query_system[6816ad35e73f53f7]::query::caches::VecCache<rustc_span[7d331dab010f821e]::def_id::LocalDefId, rustc_middle[eadc16aa5b2d798c]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[52c3636fd1c621b8]::plumbing::QueryCtxt, false>
  28:     0x7fb545e15c90 - rustc_query_impl[52c3636fd1c621b8]::query_impl::typeck::get_query_non_incr::__rust_end_short_backtrace
  29:     0x7fb54623afaf - <rustc_middle[eadc16aa5b2d798c]::hir::map::Map>::par_body_owners::<rustc_hir_analysis[b169b98e228215e2]::check_crate::{closure#7}>::{closure#0}
  30:     0x7fb5462397a5 - rustc_hir_analysis[b169b98e228215e2]::check_crate
  31:     0x7fb5465548a9 - rustc_interface[d612fcec1432366d]::passes::analysis
  32:     0x7fb5465544dd - rustc_query_impl[52c3636fd1c621b8]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[52c3636fd1c621b8]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[eadc16aa5b2d798c]::query::erase::Erased<[u8; 1usize]>>
  33:     0x7fb546b9f900 - rustc_query_system[6816ad35e73f53f7]::query::plumbing::try_execute_query::<rustc_query_impl[52c3636fd1c621b8]::DynamicConfig<rustc_query_system[6816ad35e73f53f7]::query::caches::SingleCache<rustc_middle[eadc16aa5b2d798c]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[52c3636fd1c621b8]::plumbing::QueryCtxt, false>
  34:     0x7fb546b9f707 - rustc_query_impl[52c3636fd1c621b8]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  35:     0x7fb546c36752 - rustc_interface[d612fcec1432366d]::interface::run_compiler::<core[14b734a3e12aace1]::result::Result<(), rustc_span[7d331dab010f821e]::ErrorGuaranteed>, rustc_driver_impl[8fbc4de111867a14]::run_compiler::{closure#0}>::{closure#0}
  36:     0x7fb546bbe706 - std[855c18717e34e1aa]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[d612fcec1432366d]::util::run_in_thread_with_globals<rustc_interface[d612fcec1432366d]::util::run_in_thread_pool_with_globals<rustc_interface[d612fcec1432366d]::interface::run_compiler<core[14b734a3e12aace1]::result::Result<(), rustc_span[7d331dab010f821e]::ErrorGuaranteed>, rustc_driver_impl[8fbc4de111867a14]::run_compiler::{closure#0}>::{closure#0}, core[14b734a3e12aace1]::result::Result<(), rustc_span[7d331dab010f821e]::ErrorGuaranteed>>::{closure#0}, core[14b734a3e12aace1]::result::Result<(), rustc_span[7d331dab010f821e]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[14b734a3e12aace1]::result::Result<(), rustc_span[7d331dab010f821e]::ErrorGuaranteed>>
  37:     0x7fb546bbe533 - <<std[855c18717e34e1aa]::thread::Builder>::spawn_unchecked_<rustc_interface[d612fcec1432366d]::util::run_in_thread_with_globals<rustc_interface[d612fcec1432366d]::util::run_in_thread_pool_with_globals<rustc_interface[d612fcec1432366d]::interface::run_compiler<core[14b734a3e12aace1]::result::Result<(), rustc_span[7d331dab010f821e]::ErrorGuaranteed>, rustc_driver_impl[8fbc4de111867a14]::run_compiler::{closure#0}>::{closure#0}, core[14b734a3e12aace1]::result::Result<(), rustc_span[7d331dab010f821e]::ErrorGuaranteed>>::{closure#0}, core[14b734a3e12aace1]::result::Result<(), rustc_span[7d331dab010f821e]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[14b734a3e12aace1]::result::Result<(), rustc_span[7d331dab010f821e]::ErrorGuaranteed>>::{closure#1} as core[14b734a3e12aace1]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  38:     0x7fb547bf6945 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h6a024772f7810b01
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/alloc/src/boxed.rs:2015:9
  39:     0x7fb547bf6945 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h5739f1057fc9bfd8
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/alloc/src/boxed.rs:2015:9
  40:     0x7fb547bf6945 - std::sys::unix::thread::Thread::new::thread_start::hd654374c5da395df
                               at /rustc/ca9ff83f1be558d4ce0a9a49b3d4d25034e5bd1e/library/std/src/sys/unix/thread.rs:108:17
  41:     0x7fb541aaa9eb - <unknown>
  42:     0x7fb541b2e7cc - <unknown>
  43:                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: rustc 1.77.0-nightly (ca9ff83f1 2023-12-27) running on x86_64-unknown-linux-gnu

query stack during panic:
#0 [typeck] type-checking `serial_init`
#1 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 3 previous errors

Some errors have detailed explanations: E0425, E0601.
For more information about an error, try `rustc --explain E0425`.

[matthiaskrgr]

Regression in #118431 cc sjwang05

[sjwang05]

@rustbot claim

[estebank]

@sjwang05 just to jump start, I just checked the contents of inner in the case presented:

 INFO rustc_trait_selection::traits::error_reporting::suggestions inner.trait_ref.args=[str], inner.trait_ref=<str as std::marker::Sized>

I'm checking what breaks in the test suite if we change the slicing to args[1..] (which intuitively makes more sense but am still trying to piece things together). Edit: Ah, yeah, that won't work.

[sjwang05]

Thanks for the help, turns out I could've just used iter().skip(2) instead of slicing all along 🤦. I'll submit the PR once the test suite finishes running locally.

As a side note, do you know why some binops seem to have 3 args? Intuitively it'd make sense to only have 2 args for the lhs and rhs tys--my guess is that the "extra" arg is something effects-related, but I'm not familiar at all with that part of the code.