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Compiler crashes on a piece of code that misses some parenthesis around a tuple contained in Result::Ok #94334

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rgiot opened this issue Feb 24, 2022 · 3 comments · Fixed by #94438
Closed

Compiler crashes on a piece of code that misses some parenthesis around a tuple contained in Result::Ok #94334

rgiot opened this issue Feb 24, 2022 · 3 comments · Fixed by #94438
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@compiler-errors
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C-bug Category: This is a bug. I-ICE Issue: The compiler panicked, giving an Internal Compilation Error (ICE) ❄️ regression-from-stable-to-beta Performance or correctness regression from stable to beta. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue.

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@rgiot
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rgiot commented Feb 24, 2022 •
edited by rustbot
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I am doing deep modifications to an existing program that was not raising compilation issues.
It is not yet finished, it is probably not nice rust code, but I am reaching a point where it make crashe the compiler.
You can reproduce it with:

git clone --depth=1 --branch rustc_crash https://github.com/cpcsdk/rust.cpclib.git
cd rust.cpclib/cpclib-asm/ && cargo +nightly build

I have to admit that I do not really know how to guide more to find the reason. But I can make specific tests on request.
I would say it is realted to issue #94291

Code

Here is the problematic code:

fn located_expr(input: Z80Span) -> IResult<Z80Span, LocatedExpr, VerboseError<Z80Span>> {
    let start = input.clone();
    let (stop, exp) = expr(input)?;
    Ok(
        stop,
        LocatedExpr::new(exp, start.take(stop.input_len()-start.input_len()))
    )
}

When trying to reproducing it with this minimal example

use nom::{IResult, error::VerboseError, bytes::complete::tag, InputTake, InputLength};


type Z80Span = nom_locate::LocatedSpan<&'static str>;
struct Expr();
struct LocatedExpr(Expr, Z80Span);
impl LocatedExpr {
    fn new(expr: Expr, span: Z80Span) -> Self {
        todo!();
    }
}

fn expr(input: Z80Span) -> IResult<Z80Span, Expr, VerboseError<Z80Span>> {
    todo!()
}

fn located_expr(input: Z80Span) -> IResult<Z80Span, LocatedExpr, VerboseError<Z80Span>> {
    let start = input.clone();
    let (stop, exp) = expr(input)?;
    Ok(
        stop,
        LocatedExpr::new(exp, start.take(stop.input_len() - start.input_len()))
    )
}

The compiler does not crashes, but raises the following error:

error[E0061]: this enum variant takes 1 argument but 2 arguments were supplied
  --> src/lib.rs:20:5
   |
20 |     Ok(
   |     ^^ expected 1 argument
21 |         stop,
   |         ----
22 |         LocatedExpr::new(exp, start.take(stop.input_len() - start.input_len()))
   |         ----------------------------------------------------------------------- supplied 2 arguments

If I add the missing pair of parenthesis for the tuple contained in Ok in my project, the compiler does not crashes anymore. (Maybe it means the bug is after the detection of these missing parenthesis).

Meta

rustc --version --verbose:

rustc 1.61.0-nightly (532d3cda9 2022-02-23)
binary: rustc
commit-hash: 532d3cda90b8a729cd982548649d32803d265052
commit-date: 2022-02-23
host: x86_64-unknown-linux-gnu
release: 1.61.0-nightly
LLVM version: 14.0.0

Error output

error: internal compiler error: compiler/rustc_typeck/src/check/fn_ctxt/_impl.rs:318:26: while adjusting Expr { hir_id: HirId { owner: DefId(0:984 ~ cpclib_asm[cd45]::parser::parser::located_expr), local_id: 48 }, kind: Path(Resolved(None, Path { span: cpclib-asm/src/parser/parser.rs:3919:31: 3919:36 (#0), res: Local(HirId { owner: DefId(0:984 ~ cpclib_asm[cd45]::parser::parser::located_expr), local_id: 9 }), segments: [PathSegment { ident: start#0, hir_id: Some(HirId { owner: DefId(0:984 ~ cpclib_asm[cd45]::parser::parser::located_expr), local_id: 47 }), res: Some(Local(HirId { owner: DefId(0:984 ~ cpclib_asm[cd45]::parser::parser::located_expr), local_id: 9 })), args: None, infer_args: true }] })), span: cpclib-asm/src/parser/parser.rs:3919:31: 3919:36 (#0) }, can't compose [Borrow(Ref('_#2r, Not)) -> &source::Z80Span] and [Borrow(Ref('_#8r, Not)) -> &source::Z80Span]

note: the compiler unexpectedly panicked. this is a bug.
Backtrace 


thread 'rustc' panicked at 'Box<dyn Any>', compiler/rustc_errors/src/lib.rs:1160:9
stack backtrace:
   0:     0x7f09b1552d2c - std::backtrace_rs::backtrace::libunwind::trace::ha6a3383edab6e13f
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7f09b1552d2c - std::backtrace_rs::backtrace::trace_unsynchronized::h7678ada881e148be
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f09b1552d2c - std::sys_common::backtrace::_print_fmt::h0fccf51c6aaaecaa
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/sys_common/backtrace.rs:66:5
   3:     0x7f09b1552d2c - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hd62bee1af47947a0
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/sys_common/backtrace.rs:45:22
   4:     0x7f09b15b29dc - core::fmt::write::ha9439145beb73667
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/core/src/fmt/mod.rs:1190:17
   5:     0x7f09b1542e58 - std::io::Write::write_fmt::h6c29ca798b983a86
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/io/mod.rs:1657:15
   6:     0x7f09b1556d07 - std::sys_common::backtrace::_print::h3035fd29ed56746e
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/sys_common/backtrace.rs:48:5
   7:     0x7f09b1556d07 - std::sys_common::backtrace::print::h67b4e33a29e4428d
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/sys_common/backtrace.rs:35:9
   8:     0x7f09b1556d07 - std::panicking::default_hook::{{closure}}::h82b81eb8bc9dd6ef
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/panicking.rs:295:22
   9:     0x7f09b15569bf - std::panicking::default_hook::h2bb2e237c5c6b178
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/panicking.rs:314:9
  10:     0x7f09b1cec111 - rustc_driver[26d3d5263add57]::DEFAULT_HOOK::{closure#0}::{closure#0}
  11:     0x7f099c85e423 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h2048d48fe6c1b2ad
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/alloc/src/boxed.rs:1868:9
  12:     0x7f099c8919ac - proc_macro::bridge::client::<impl proc_macro::bridge::Bridge>::enter::{{closure}}::{{closure}}::h54144fafa68fac7a
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/proc_macro/src/bridge/client.rs:319:21
  13:     0x7f099c890c70 - std::panicking::update_hook::{{closure}}::h19bf199960f99baf
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/panicking.rs:258:41
  14:     0x7f09b15575d6 - std::panicking::rust_panic_with_hook::hdbef34545998f799
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/panicking.rs:702:17
  15:     0x7f09b2dc1d71 - std[159a6a17188a9e73]::panicking::begin_panic::<rustc_errors[a8dffc0962701d3a]::ExplicitBug>::{closure#0}
  16:     0x7f09b2dc1cd6 - std[159a6a17188a9e73]::sys_common::backtrace::__rust_end_short_backtrace::<std[159a6a17188a9e73]::panicking::begin_panic<rustc_errors[a8dffc0962701d3a]::ExplicitBug>::{closure#0}, !>
  17:     0x7f09b2dc81cf - std[159a6a17188a9e73]::panicking::begin_panic::<rustc_errors[a8dffc0962701d3a]::ExplicitBug>
  18:     0x7f09b2dd52fd - std[159a6a17188a9e73]::panic::panic_any::<rustc_errors[a8dffc0962701d3a]::ExplicitBug>
  19:     0x7f09b2dd4587 - <rustc_errors[a8dffc0962701d3a]::HandlerInner>::bug
  20:     0x7f09b2dd4080 - <rustc_errors[a8dffc0962701d3a]::Handler>::bug
  21:     0x7f09b2c50421 - rustc_middle[98146359f81daf65]::ty::context::tls::with_opt::<rustc_middle[98146359f81daf65]::util::bug::opt_span_bug_fmt<rustc_span[7d35b7cf06b95e2a]::span_encoding::Span>::{closure#0}, ()>
  22:     0x7f09b2c50650 - rustc_middle[98146359f81daf65]::util::bug::opt_span_bug_fmt::<rustc_span[7d35b7cf06b95e2a]::span_encoding::Span>
  23:     0x7f09b2c505c6 - rustc_middle[98146359f81daf65]::util::bug::bug_fmt
  24:     0x7f09b30cc1da - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::apply_adjustments
  25:     0x7f09b3152718 - <rustc_typeck[c75d5fa9d82901dd]::check::method::confirm::ConfirmContext>::confirm
  26:     0x7f09b30d48c3 - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::lookup_method
  27:     0x7f09b30bf23b - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::check_expr_kind
  28:     0x7f09b30a4808 - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::check_argument_types
  29:     0x7f09b3081738 - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::check_call
  30:     0x7f09b30bf15c - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::check_expr_kind
  31:     0x7f09b30a4808 - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::check_argument_types
  32:     0x7f09b3081738 - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::check_call
  33:     0x7f09b30bf15c - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::check_expr_kind
  34:     0x7f09b30bd102 - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::check_expr_with_expectation
  35:     0x7f09b30ab854 - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::check_block_with_expected
  36:     0x7f09b30bd102 - <rustc_typeck[c75d5fa9d82901dd]::check::fn_ctxt::FnCtxt>::check_expr_with_expectation
  37:     0x7f09b31bd4ed - rustc_typeck[c75d5fa9d82901dd]::check::check::check_fn
  38:     0x7f09b313932a - <rustc_infer[6a8a85696ee20aa1]::infer::InferCtxtBuilder>::enter::<&rustc_middle[98146359f81daf65]::ty::context::TypeckResults, <rustc_typeck[c75d5fa9d82901dd]::check::inherited::InheritedBuilder>::enter<rustc_typeck[c75d5fa9d82901dd]::check::typeck_with_fallback<rustc_typeck[c75d5fa9d82901dd]::check::typeck::{closure#0}>::{closure#1}, &rustc_middle[98146359f81daf65]::ty::context::TypeckResults>::{closure#0}>
  39:     0x7f09b311a69d - rustc_typeck[c75d5fa9d82901dd]::check::typeck
  40:     0x7f09b40ebe10 - <rustc_query_system[e5ce915dae2fd7e8]::dep_graph::graph::DepGraph<rustc_middle[98146359f81daf65]::dep_graph::dep_node::DepKind>>::with_task::<rustc_middle[98146359f81daf65]::ty::context::TyCtxt, rustc_span[7d35b7cf06b95e2a]::def_id::LocalDefId, &rustc_middle[98146359f81daf65]::ty::context::TypeckResults>
  41:     0x7f09b35d2a48 - rustc_query_system[e5ce915dae2fd7e8]::query::plumbing::try_execute_query::<rustc_query_impl[c516436ef3f447dc]::plumbing::QueryCtxt, rustc_query_system[e5ce915dae2fd7e8]::query::caches::DefaultCache<rustc_span[7d35b7cf06b95e2a]::def_id::LocalDefId, &rustc_middle[98146359f81daf65]::ty::context::TypeckResults>>
  42:     0x7f09b3629a0c - <rustc_query_impl[c516436ef3f447dc]::Queries as rustc_middle[98146359f81daf65]::ty::query::QueryEngine>::typeck
  43:     0x7f09b317a42a - <rustc_middle[98146359f81daf65]::hir::map::Map>::par_body_owners::<rustc_typeck[c75d5fa9d82901dd]::check::typeck_item_bodies::{closure#0}>
  44:     0x7f09b3e10dec - rustc_typeck[c75d5fa9d82901dd]::check::typeck_item_bodies
  45:     0x7f09b410ac21 - <rustc_query_system[e5ce915dae2fd7e8]::dep_graph::graph::DepGraph<rustc_middle[98146359f81daf65]::dep_graph::dep_node::DepKind>>::with_task::<rustc_middle[98146359f81daf65]::ty::context::TyCtxt, (), ()>
  46:     0x7f09b405712c - rustc_query_system[e5ce915dae2fd7e8]::query::plumbing::try_execute_query::<rustc_query_impl[c516436ef3f447dc]::plumbing::QueryCtxt, rustc_query_system[e5ce915dae2fd7e8]::query::caches::DefaultCache<(), ()>>
  47:     0x7f09b407fa88 - rustc_query_system[e5ce915dae2fd7e8]::query::plumbing::get_query::<rustc_query_impl[c516436ef3f447dc]::queries::typeck_item_bodies, rustc_query_impl[c516436ef3f447dc]::plumbing::QueryCtxt>
  48:     0x7f09b3e14cb9 - <rustc_session[9a0814f637980201]::session::Session>::time::<(), rustc_typeck[c75d5fa9d82901dd]::check_crate::{closure#7}>
  49:     0x7f09b3e114e3 - rustc_typeck[c75d5fa9d82901dd]::check_crate
  50:     0x7f09b3b9e877 - rustc_interface[773294294e34a240]::passes::analysis
  51:     0x7f09b4106f70 - <rustc_query_system[e5ce915dae2fd7e8]::dep_graph::graph::DepGraph<rustc_middle[98146359f81daf65]::dep_graph::dep_node::DepKind>>::with_task::<rustc_middle[98146359f81daf65]::ty::context::TyCtxt, (), core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>>
  52:     0x7f09b404ce40 - rustc_query_system[e5ce915dae2fd7e8]::query::plumbing::try_execute_query::<rustc_query_impl[c516436ef3f447dc]::plumbing::QueryCtxt, rustc_query_system[e5ce915dae2fd7e8]::query::caches::DefaultCache<(), core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>>>
  53:     0x7f09b408eb65 - rustc_query_system[e5ce915dae2fd7e8]::query::plumbing::get_query::<rustc_query_impl[c516436ef3f447dc]::queries::analysis, rustc_query_impl[c516436ef3f447dc]::plumbing::QueryCtxt>
  54:     0x7f09b3b7c8f8 - <rustc_interface[773294294e34a240]::passes::QueryContext>::enter::<rustc_driver[26d3d5263add57]::run_compiler::{closure#1}::{closure#2}::{closure#3}, core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>>
  55:     0x7f09b3b6bb6a - <rustc_interface[773294294e34a240]::interface::Compiler>::enter::<rustc_driver[26d3d5263add57]::run_compiler::{closure#1}::{closure#2}, core[b1995bd94a57dbad]::result::Result<core[b1995bd94a57dbad]::option::Option<rustc_interface[773294294e34a240]::queries::Linker>, rustc_errors[a8dffc0962701d3a]::ErrorReported>>
  56:     0x7f09b3b6dd66 - rustc_span[7d35b7cf06b95e2a]::with_source_map::<core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>, rustc_interface[773294294e34a240]::interface::create_compiler_and_run<core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>, rustc_driver[26d3d5263add57]::run_compiler::{closure#1}>::{closure#1}>
  57:     0x7f09b3b6b571 - rustc_interface[773294294e34a240]::interface::create_compiler_and_run::<core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>, rustc_driver[26d3d5263add57]::run_compiler::{closure#1}>
  58:     0x7f09b3b56e72 - <scoped_tls[54534a13b092d0ba]::ScopedKey<rustc_span[7d35b7cf06b95e2a]::SessionGlobals>>::set::<rustc_interface[773294294e34a240]::interface::run_compiler<core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>, rustc_driver[26d3d5263add57]::run_compiler::{closure#1}>::{closure#0}, core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>>
  59:     0x7f09b3b5672d - std[159a6a17188a9e73]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[773294294e34a240]::util::run_in_thread_pool_with_globals<rustc_interface[773294294e34a240]::interface::run_compiler<core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>, rustc_driver[26d3d5263add57]::run_compiler::{closure#1}>::{closure#0}, core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>>::{closure#0}, core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>>
  60:     0x7f09b3b54f19 - <<std[159a6a17188a9e73]::thread::Builder>::spawn_unchecked_<rustc_interface[773294294e34a240]::util::run_in_thread_pool_with_globals<rustc_interface[773294294e34a240]::interface::run_compiler<core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>, rustc_driver[26d3d5263add57]::run_compiler::{closure#1}>::{closure#0}, core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>>::{closure#0}, core[b1995bd94a57dbad]::result::Result<(), rustc_errors[a8dffc0962701d3a]::ErrorReported>>::{closure#1} as core[b1995bd94a57dbad]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  61:     0x7f09b1563163 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hed4bb989451a58dc
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/alloc/src/boxed.rs:1854:9
  62:     0x7f09b1563163 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::ha3b82106bd47d0e3
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/alloc/src/boxed.rs:1854:9
  63:     0x7f09b1563163 - std::sys::unix::thread::Thread::new::thread_start::h170b42a5b9d0a9fe
                               at /rustc/532d3cda90b8a729cd982548649d32803d265052/library/std/src/sys/unix/thread.rs:108:17
  64:     0x7f09b12fc927 - start_thread
                               at ./nptl/./nptl/pthread_create.c:435:8
  65:     0x7f09b138c9e4 - __clone
                               at ./misc/../sysdeps/unix/sysv/linux/x86_64/clone.S:100
  66:                0x0 - <unknown>

Additional Trace

query stack during panic:
#0 [typeck] type-checking `parser::parser::located_expr`
#1 [typeck_item_bodies] type-checking all item bodies
#2 [analysis] running analysis passes on this crate
end of query stack
@rgiot rgiot added C-bug Category: This is a bug. I-ICE Issue: The compiler panicked, giving an Internal Compilation Error (ICE) ❄️ T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Feb 24, 2022
@compiler-errors
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@ouz-a, does #94355 fix this? (or is it related)

@ouz-a
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ouz-a commented Feb 26, 2022

@ouz-a, does #94355 fix this? (or is it related)

My pr doesn't fix this but it sure looks like these are related.

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compiler-errors commented Feb 26, 2022 •
edited
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I have a PR that generalizes the fix in #94355, I think I understand the root cause.

@rustbot claim

@compiler-errors compiler-errors mentioned this issue Feb 28, 2022
Merged
@bors bors closed this as completed in 2353e83 Mar 1, 2022
@tmiasko tmiasko added the regression-from-stable-to-beta Performance or correctness regression from stable to beta. label Mar 3, 2022
@rustbot rustbot added the I-prioritize Issue: Indicates that prioritization has been requested for this issue. label Mar 3, 2022
@compiler-errors compiler-errors mentioned this issue Mar 5, 2022
Merged
matthiaskrgr added a commit to matthiaskrgr/rust that referenced this issue Mar 7, 2022
@matthiaskrgr
Rollup merge of rust-lang#94636 - compiler-errors:issue-94599, r=davi…
9c7ff1a 
…dtwco

Check extra function arg exprs even if the fn is not C-variadic

We should still call check_expr on the args that exceed the formal input ty count, so that we have expr types to emit during writeback.

Not sure where this regressed, but it wasn't due to the same root cause as rust-lang#94334 I think. I thought this might've regressed in rust-lang#92360, but I think that is in stable, ad the test I provided (which minimizes rust-lang#94599) passes on stable in playground. Maybe it regressed in rust-lang#93118.

Anywho, fixes rust-lang#94599.
@apiraino apiraino removed the I-prioritize Issue: Indicates that prioritization has been requested for this issue. label Mar 10, 2022
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C-bug Category: This is a bug. I-ICE Issue: The compiler panicked, giving an Internal Compilation Error (ICE) ❄️ regression-from-stable-to-beta Performance or correctness regression from stable to beta. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue.
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Check method input expressions once compiler-errors/rust
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@rgiot @compiler-errors @apiraino @rustbot @tmiasko @ouz-a