ICE with `generic_const_exprs` and `adt_const_params`

[Kixiron]

Code

pub struct Changes<const CHANGES: &'static [&'static str]>
where
    [(); CHANGES.len()]:,
{
    changes: [usize; CHANGES.len()],
    has_changed: bool,
}

impl<const CHANGES: &'static [&'static str]> Changes<CHANGES>
where
    [(); CHANGES.len()]:,
{
    pub const fn new() -> Self {
        Self {
            changes: [0; CHANGES.len()],
            has_changed: false,
        }
    }

    pub const fn did_change(&self) -> bool {
        self.has_changed
    }

    pub fn reset(&mut self) {
        self.has_changed = false;
    }

    pub fn combine(&mut self, other: &Self) {
        self.has_changed |= other.has_changed;

        // Sum up all changes
        self.changes
            .iter_mut()
            .zip(&other.changes)
            .for_each(|(total, &additional)| *total += additional);
    }

    pub fn inc<const NAME: &'static str>(&mut self)
    where
        Assert<{ contains(CHANGES, NAME) }>: True,
    {
        self.has_changed = true;

        let index = index_of(CHANGES, NAME);
        self.changes[index] += 1;
    }
}

pub struct Assert<const COND: bool> {}

pub trait True {}

impl True for Assert<true> {}

pub const fn contains(changes: &[&str], name: &str) -> bool {
    let mut idx = 0;
    while idx < changes.len() {
        if str_eq(changes[idx], name) {
            return true;
        }

        idx += 1;
    }

    false
}

const fn index_of(changes: &[&str], name: &str) -> usize {
    let mut idx = 0;
    while idx < changes.len() {
        if str_eq(changes[idx], name) {
            return idx;
        }

        idx += 1;
    }

    panic!()
}

const fn str_eq(lhs: &str, rhs: &str) -> bool {
    let (lhs, rhs) = (lhs.as_bytes(), rhs.as_bytes());

    if lhs.len() != rhs.len() {
        return false;
    }

    let mut idx = 0;
    while idx < lhs.len() {
        if lhs[idx] != rhs[idx] {
            return false;
        }

        idx += 1;
    }

    true
}

Meta

rustc --version --verbose:

rustc 1.62.0-nightly (6dd68402c 2022-05-11)
binary: rustc
commit-hash: 6dd68402c5d7da168f87d8551dd9aed1d8a21893
commit-date: 2022-05-11
host: x86_64-pc-windows-msvc
release: 1.62.0-nightly
LLVM version: 14.0.1

Error output

warning: Error finalizing incremental compilation session directory `\\?\G:\Users\Chase\Code\Rust\cranial-coitus\target\debug\incremental\cranial_coitus-2hk2617a5lyqj\s-g9s3rzollv-1ifjoz6-working`: The system cannot find the file specified. (os error 2)

error: internal compiler error: no errors encountered even though `delay_span_bug` issued

error: internal compiler error: broken MIR in DefId(0:7398 ~ cranial_coitus[a396]::passes::utils::changes::{impl#1}::new) (NoSolution): could not prove Binder(ConstEvaluatable(WithOptConstParam { did: DefId(0:7391 ~ cranial_coitus[a396]::passes::utils::changes::Changes2::{constant#0}), const_param_did: None }, [Const { ty: &[&str], val: Param(CHANGES/#0) }]), [])
  --> src\passes\utils\changes.rs:78:9
   |
78 | /         Self {
79 | |             changes: [0; CHANGES.len()],
80 | |             has_changed: false,
81 | |         }
   | |_________^
   |
   = note: delayed at compiler\rustc_borrowck\src\type_check\canonical.rs:149:13

error: internal compiler error: broken MIR in DefId(0:7402 ~ cranial_coitus[a396]::passes::utils::changes::{impl#1}::combine) (NoSolution): could not prove Binder(WellFormed(&[usize; _]), [])
  --> src\passes\utils\changes.rs:98:18
   |
98 |             .zip(&other.changes)
   |                  ^^^^^^^^^^^^^^
   |
   = note: delayed at compiler\rustc_borrowck\src\type_check\canonical.rs:149:13

error: internal compiler error: broken MIR in DefId(0:7402 ~ cranial_coitus[a396]::passes::utils::changes::{impl#1}::combine) (NoSolution): could not prove Binder(ConstEvaluatable(WithOptConstParam { did: DefId(0:7397 ~ cranial_coitus[a396]::passes::utils::changes::{impl#1}::{constant#0}), const_param_did: None }, [Const { ty: &[&str], val: Param(CHANGES/#0) }]), [])
  --> src\passes\utils\changes.rs:99:23
   |
99 |             .for_each(|(total, &additional)| *total += additional);
   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: delayed at compiler\rustc_borrowck\src\type_check\canonical.rs:149:13

thread 'rustc' panicked at 'Box<dyn Any>', compiler\rustc_errors\src\lib.rs:1369:13
stack backtrace:
   0:     0x7ff8fe65988f - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h19d347d7cfe5cdb5
   1:     0x7ff8fe69496a - core::fmt::write::ha4c3b8e240caf9f6
   2:     0x7ff8fe64bea9 - <std::io::IoSlice as core::fmt::Debug>::fmt::hc3dee57d919433ff
   3:     0x7ff8fe65d07b - std::panicking::default_hook::h4544884403d9be85
   4:     0x7ff8fe65cc6e - std::panicking::default_hook::h4544884403d9be85
   5:     0x7ff8cb47e8c9 - <rustc_middle[dba4d5507afbab0d]::ty::SymbolName as core[eee2e1d8d36d089]::fmt::Debug>::fmt
   6:     0x7ff8fe65d95a - std::panicking::rust_panic_with_hook::hc1cc4992a4b6ec1b
   7:     0x7ff8cfbe3055 - <rustc_errors[a795d8b482c20b3d]::diagnostic_builder::DiagnosticBuilderInner as core[eee2e1d8d36d089]::ops::drop::Drop>::drop
   8:     0x7ff8cfbe3009 - <rustc_errors[a795d8b482c20b3d]::diagnostic_builder::DiagnosticBuilderInner as core[eee2e1d8d36d089]::ops::drop::Drop>::drop
   9:     0x7ff8cff29399 - rustc_query_system[a0b9f5f0299a8a38]::query::plumbing::incremental_verify_ich_cold
  10:     0x7ff8cfbd5629 - <rustc_feature[ea871e0fc9abb418]::builtin_attrs::AttributeType as core[eee2e1d8d36d089]::fmt::Debug>::fmt
  11:     0x7ff8cfbd9288 - <rustc_errors[a795d8b482c20b3d]::HandlerInner as core[eee2e1d8d36d089]::ops::drop::Drop>::drop
  12:     0x7ff8cb4a5794 - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  13:     0x7ff8cb4a8bca - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  14:     0x7ff8cb493ecd - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  15:     0x7ff8cb491bf9 - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  16:     0x7ff8cb42f540 - <rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::PtxLinker as rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::Linker>::no_default_libraries
  17:     0x7ff8cb432c27 - <rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::PtxLinker as rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::Linker>::no_default_libraries
  18:     0x7ff8cb43c876 - <rustc_driver[dba66f49bbdf914a]::args::Error as core[eee2e1d8d36d089]::fmt::Debug>::fmt
  19:     0x7ff8cb43d998 - <rustc_driver[dba66f49bbdf914a]::args::Error as core[eee2e1d8d36d089]::fmt::Debug>::fmt
  20:     0x7ff8fe66edec - std::sys::windows::thread::Thread::new::h1883b00da4b4f517
  21:     0x7ff95ba97034 - BaseThreadInitThunk
  22:     0x7ff95d2a2651 - RtlUserThreadStart

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 1.62.0-nightly (6dd68402c 2022-05-11) running on x86_64-pc-windows-msvc

note: compiler flags: --crate-type bin -C embed-bitcode=no -C debuginfo=2 -C incremental

note: some of the compiler flags provided by cargo are hidden

query stack during panic:
end of query stack
warning: `cranial-coitus` (bin "cranial-coitus") generated 56 warnings
error: could not compile `cranial-coitus`; 56 warnings emitted

Backtrace

warning: Error finalizing incremental compilation session directory `\\?\G:\Users\Chase\Code\Rust\cranial-coitus\target\debug\incremental\cranial_coitus-2hk2617a5lyqj\s-g9s4782zug-1fg2gpo-working`: The system cannot find the file specified. (os error 2)

error: internal compiler error: no errors encountered even though `delay_span_bug` issued

error: internal compiler error: broken MIR in DefId(0:7410 ~ cranial_coitus[a396]::passes::utils::changes::const_checked::{impl#0}::new) (NoSolution): could not prove Binder(ConstEvaluatable(WithOptConstParam { did: DefId(0:7403 ~ cranial_coitus[a396]::passes::utils::changes::const_checked::Changes2::{constant#0}), const_param_did: None }, [Const { ty: &[&str], val: Param(CHANGES/#0) }]), [])
  --> src\passes\utils\changes.rs:84:13
   |
84 | /             Self {
85 | |                 changes: [0; CHANGES.len()],
86 | |                 has_changed: false,
87 | |             }
   | |_____________^
   |
   = note: delayed at compiler\rustc_borrowck\src\type_check\canonical.rs:149:13

error: internal compiler error: broken MIR in DefId(0:7414 ~ cranial_coitus[a396]::passes::utils::changes::const_checked::{impl#0}::combine) (NoSolution): could not prove Binder(WellFormed(&[usize; _]), [])
   --> src\passes\utils\changes.rs:104:22
    |
104 |                 .zip(&other.changes)
    |                      ^^^^^^^^^^^^^^
    |
    = note: delayed at compiler\rustc_borrowck\src\type_check\canonical.rs:149:13

error: internal compiler error: broken MIR in DefId(0:7414 ~ cranial_coitus[a396]::passes::utils::changes::const_checked::{impl#0}::combine) (NoSolution): could not prove Binder(ConstEvaluatable(WithOptConstParam { did: DefId(0:7409 ~ cranial_coitus[a396]::passes::utils::changes::const_checked::{impl#0}::{constant#0}), const_param_did: None }, [Const { ty: &[&str], val: Param(CHANGES/#0) }]), [])
   --> src\passes\utils\changes.rs:105:27
    |
105 |                 .for_each(|(total, &additional)| *total += additional);
    |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: delayed at compiler\rustc_borrowck\src\type_check\canonical.rs:149:13

thread 'rustc' panicked at 'Box<dyn Any>', compiler\rustc_errors\src\lib.rs:1369:13
stack backtrace:
   0:     0x7ff8fe65988f - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h19d347d7cfe5cdb5
   1:     0x7ff8fe69496a - core::fmt::write::ha4c3b8e240caf9f6
   2:     0x7ff8fe64bea9 - <std::io::IoSlice as core::fmt::Debug>::fmt::hc3dee57d919433ff
   3:     0x7ff8fe65d07b - std::panicking::default_hook::h4544884403d9be85
   4:     0x7ff8fe65cc6e - std::panicking::default_hook::h4544884403d9be85
   5:     0x7ff8cb47e8c9 - <rustc_middle[dba4d5507afbab0d]::ty::SymbolName as core[eee2e1d8d36d089]::fmt::Debug>::fmt
   6:     0x7ff8fe65d95a - std::panicking::rust_panic_with_hook::hc1cc4992a4b6ec1b
   7:     0x7ff8cfbe3055 - <rustc_errors[a795d8b482c20b3d]::diagnostic_builder::DiagnosticBuilderInner as core[eee2e1d8d36d089]::ops::drop::Drop>::drop
   8:     0x7ff8cfbe3009 - <rustc_errors[a795d8b482c20b3d]::diagnostic_builder::DiagnosticBuilderInner as core[eee2e1d8d36d089]::ops::drop::Drop>::drop
   9:     0x7ff8cff29399 - rustc_query_system[a0b9f5f0299a8a38]::query::plumbing::incremental_verify_ich_cold
  10:     0x7ff8cfbd5629 - <rustc_feature[ea871e0fc9abb418]::builtin_attrs::AttributeType as core[eee2e1d8d36d089]::fmt::Debug>::fmt
  11:     0x7ff8cfbd9288 - <rustc_errors[a795d8b482c20b3d]::HandlerInner as core[eee2e1d8d36d089]::ops::drop::Drop>::drop
  12:     0x7ff8cb4a5794 - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  13:     0x7ff8cb4a8bca - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  14:     0x7ff8cb493ecd - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  15:     0x7ff8cb491bf9 - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  16:     0x7ff8cb42f540 - <rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::PtxLinker as rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::Linker>::no_default_libraries
  17:     0x7ff8cb432c27 - <rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::PtxLinker as rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::Linker>::no_default_libraries
  18:     0x7ff8cb43c876 - <rustc_driver[dba66f49bbdf914a]::args::Error as core[eee2e1d8d36d089]::fmt::Debug>::fmt
  19:     0x7ff8cb43d998 - <rustc_driver[dba66f49bbdf914a]::args::Error as core[eee2e1d8d36d089]::fmt::Debug>::fmt
  20:     0x7ff8fe66edec - std::sys::windows::thread::Thread::new::h1883b00da4b4f517
  21:     0x7ff95ba97034 - BaseThreadInitThunk
  22:     0x7ff95d2a2651 - RtlUserThreadStart

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 1.62.0-nightly (6dd68402c 2022-05-11) running on x86_64-pc-windows-msvc

note: compiler flags: --crate-type bin -C embed-bitcode=no -C debuginfo=2 -C incremental

note: some of the compiler flags provided by cargo are hidden

query stack during panic:
end of query stack
warning: `cranial-coitus` (bin "cranial-coitus") generated 56 warnings
error: could not compile `cranial-coitus`; 56 warnings emitted

[rodrimati1992]

A reduced version:

#![feature(adt_const_params, generic_const_exprs)]

pub struct Changes<const CHANGES: &'static [&'static str]>
where
    [(); CHANGES.len()]:,
{
    changes: [usize; CHANGES.len()],
}

impl<const CHANGES: &'static [&'static str]> Changes<CHANGES>
where
    [(); CHANGES.len()]:,
{
    pub const fn new() -> Self {
        Self {
            changes: [0; CHANGES.len()],
        }
    }
}

Error message

error: internal compiler error: no errors encountered even though `delay_span_bug` issued

error: internal compiler error: broken MIR in DefId(0:11 ~ playground[c737]::{impl#0}::new) (NoSolution): could not prove Binder(ConstEvaluatable(WithOptConstParam { did: DefId(0:5 ~ playground[c737]::Changes::{constant#0}), const_param_did: None }, [Const { ty: &[&str], val: Param(CHANGES/#0) }]), [])
  [--> src/lib.rs:15:9
](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021#)   |
15 | /         Self {
16 | |             changes: [0; CHANGES.len()],
17 | |         }
   | |_________^
   |
   = note: delayed at compiler/rustc_borrowck/src/type_check/canonical.rs:149:13

thread 'rustc' panicked at 'Box<dyn Any>', compiler/rustc_errors/src/lib.rs:1369:13
stack backtrace:
   0:     0x7f2991265fbd - std::backtrace_rs::backtrace::libunwind::trace::hfff13da9629808b3
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7f2991265fbd - std::backtrace_rs::backtrace::trace_unsynchronized::h574c052d104edbb2
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f2991265fbd - std::sys_common::backtrace::_print_fmt::hdec7c42a9aaff178
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/std/src/sys_common/backtrace.rs:66:5
   3:     0x7f2991265fbd - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h7b437db464fe2eae
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/std/src/sys_common/backtrace.rs:45:22
   4:     0x7f29912c1c4c - core::fmt::write::ha127ca1dd987811c
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/core/src/fmt/mod.rs:1196:17
   5:     0x7f2991257731 - std::io::Write::write_fmt::haed364b23f647916
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/std/src/io/mod.rs:1654:15
   6:     0x7f2991268cd5 - std::sys_common::backtrace::_print::hb1db8a563e06b2cc
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/std/src/sys_common/backtrace.rs:48:5
   7:     0x7f2991268cd5 - std::sys_common::backtrace::print::h16e06d5c2185a605
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/std/src/sys_common/backtrace.rs:35:9
   8:     0x7f2991268cd5 - std::panicking::default_hook::{{closure}}::hc4512ccdd0ac08a5
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/std/src/panicking.rs:295:22
   9:     0x7f2991268949 - std::panicking::default_hook::hf0d6585cd7a26bd4
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/std/src/panicking.rs:314:9
  10:     0x7f2991a2dff1 - rustc_driver[8ee73bb5f36af3de]::DEFAULT_HOOK::{closure#0}::{closure#0}
  11:     0x7f29912694a6 - std::panicking::rust_panic_with_hook::hb5d5e6f805719e75
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/std/src/panicking.rs:702:17
  12:     0x7f2992ba9cd1 - std[ac1b39edc8935404]::panicking::begin_panic::<rustc_errors[7358869d503cdbaa]::ExplicitBug>::{closure#0}
  13:     0x7f2992ba9c36 - std[ac1b39edc8935404]::sys_common::backtrace::__rust_end_short_backtrace::<std[ac1b39edc8935404]::panicking::begin_panic<rustc_errors[7358869d503cdbaa]::ExplicitBug>::{closure#0}, !>
  14:     0x7f2992bad906 - std[ac1b39edc8935404]::panicking::begin_panic::<rustc_errors[7358869d503cdbaa]::ExplicitBug>
  15:     0x7f2992bb19e6 - std[ac1b39edc8935404]::panic::panic_any::<rustc_errors[7358869d503cdbaa]::ExplicitBug>
  16:     0x7f2994370c41 - <rustc_errors[7358869d503cdbaa]::HandlerInner as core[295e1f7691ff5442]::ops::drop::Drop>::drop
  17:     0x7f2993ac4198 - core[295e1f7691ff5442]::ptr::drop_in_place::<rustc_session[ff20e138b897b605]::parse::ParseSess>
  18:     0x7f2993ac64b3 - <alloc[94313895c08d63e9]::rc::Rc<rustc_session[ff20e138b897b605]::session::Session> as core[295e1f7691ff5442]::ops::drop::Drop>::drop
  19:     0x7f2993ac306d - core[295e1f7691ff5442]::ptr::drop_in_place::<rustc_interface[d033f7e4bca3d7ee]::interface::Compiler>
  20:     0x7f2993ac29d4 - rustc_span[14222bfc8ecd5677]::with_source_map::<core[295e1f7691ff5442]::result::Result<(), rustc_errors[7358869d503cdbaa]::ErrorGuaranteed>, rustc_interface[d033f7e4bca3d7ee]::interface::create_compiler_and_run<core[295e1f7691ff5442]::result::Result<(), rustc_errors[7358869d503cdbaa]::ErrorGuaranteed>, rustc_driver[8ee73bb5f36af3de]::run_compiler::{closure#1}>::{closure#1}>
  21:     0x7f2993aae0c4 - rustc_interface[d033f7e4bca3d7ee]::interface::create_compiler_and_run::<core[295e1f7691ff5442]::result::Result<(), rustc_errors[7358869d503cdbaa]::ErrorGuaranteed>, rustc_driver[8ee73bb5f36af3de]::run_compiler::{closure#1}>
  22:     0x7f2993a98692 - <scoped_tls[2d60114f458dc383]::ScopedKey<rustc_span[14222bfc8ecd5677]::SessionGlobals>>::set::<rustc_interface[d033f7e4bca3d7ee]::interface::run_compiler<core[295e1f7691ff5442]::result::Result<(), rustc_errors[7358869d503cdbaa]::ErrorGuaranteed>, rustc_driver[8ee73bb5f36af3de]::run_compiler::{closure#1}>::{closure#0}, core[295e1f7691ff5442]::result::Result<(), rustc_errors[7358869d503cdbaa]::ErrorGuaranteed>>
  23:     0x7f2993aaf7bf - std[ac1b39edc8935404]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[d033f7e4bca3d7ee]::util::run_in_thread_pool_with_globals<rustc_interface[d033f7e4bca3d7ee]::interface::run_compiler<core[295e1f7691ff5442]::result::Result<(), rustc_errors[7358869d503cdbaa]::ErrorGuaranteed>, rustc_driver[8ee73bb5f36af3de]::run_compiler::{closure#1}>::{closure#0}, core[295e1f7691ff5442]::result::Result<(), rustc_errors[7358869d503cdbaa]::ErrorGuaranteed>>::{closure#0}, core[295e1f7691ff5442]::result::Result<(), rustc_errors[7358869d503cdbaa]::ErrorGuaranteed>>
  24:     0x7f2993aaf8f9 - <<std[ac1b39edc8935404]::thread::Builder>::spawn_unchecked_<rustc_interface[d033f7e4bca3d7ee]::util::run_in_thread_pool_with_globals<rustc_interface[d033f7e4bca3d7ee]::interface::run_compiler<core[295e1f7691ff5442]::result::Result<(), rustc_errors[7358869d503cdbaa]::ErrorGuaranteed>, rustc_driver[8ee73bb5f36af3de]::run_compiler::{closure#1}>::{closure#0}, core[295e1f7691ff5442]::result::Result<(), rustc_errors[7358869d503cdbaa]::ErrorGuaranteed>>::{closure#0}, core[295e1f7691ff5442]::result::Result<(), rustc_errors[7358869d503cdbaa]::ErrorGuaranteed>>::{closure#1} as core[295e1f7691ff5442]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  25:     0x7f29912733c3 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h54f496eb95d11bdf
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/alloc/src/boxed.rs:1872:9
  26:     0x7f29912733c3 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h6d49434441582c00
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/alloc/src/boxed.rs:1872:9
  27:     0x7f29912733c3 - std::sys::unix::thread::Thread::new::thread_start::hbff7f546b16d10d6
                               at /rustc/f1f721e64014863f41c1a386b04af04c2de25321/library/std/src/sys/unix/thread.rs:108:17
  28:     0x7f29911a3609 - start_thread
  29:     0x7f29910bc133 - clone
  30:                0x0 - <unknown>

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 1.62.0-nightly (f1f721e64 2022-05-13) 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

Rust version

Tested in play.rust-lang.org using 1.62.0-nightly (2022-05-13 f1f721e64014863f41c1)

[Kixiron]

The other ICE block is also standalone

#![feature(adt_const_params, generic_const_exprs)]

pub struct Changes<const CHANGES: &'static [&'static str]>
where
    [(); CHANGES.len()]:,
{
    changes: [usize; CHANGES.len()],
}

impl<const CHANGES: &'static [&'static str]> Changes<CHANGES>
where
    [(); CHANGES.len()]:,
{
    pub fn combine(&mut self, other: &Self) {
        for _change in &self.changes {}
    }
}

error: internal compiler error: no errors encountered even though `delay_span_bug` issued

error: internal compiler error: broken MIR in DefId(0:7397 ~ cranial_coitus[a396]::passes::utils::changes::{impl#1}::combine) (NoSolution): could not prove Binder(WellFormed(&[usize; _]), [])
  --> src\passes\utils\changes.rs:75:24
   |
75 |         for _change in &self.changes {}
   |                        ^^^^^^^^^^^^^
   |
   = note: delayed at compiler\rustc_borrowck\src\type_check\canonical.rs:149:13

thread 'rustc' panicked at 'Box<dyn Any>', compiler\rustc_errors\src\lib.rs:1369:13
stack backtrace:
   0:     0x7ff8fe65988f - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h19d347d7cfe5cdb5
   1:     0x7ff8fe69496a - core::fmt::write::ha4c3b8e240caf9f6
   2:     0x7ff8fe64bea9 - <std::io::IoSlice as core::fmt::Debug>::fmt::hc3dee57d919433ff
   3:     0x7ff8fe65d07b - std::panicking::default_hook::h4544884403d9be85
   4:     0x7ff8fe65cc6e - std::panicking::default_hook::h4544884403d9be85
   5:     0x7ff8cb47e8c9 - <rustc_middle[dba4d5507afbab0d]::ty::SymbolName as core[eee2e1d8d36d089]::fmt::Debug>::fmt
   6:     0x7ff8fe65d95a - std::panicking::rust_panic_with_hook::hc1cc4992a4b6ec1b
   7:     0x7ff8cfbe3055 - <rustc_errors[a795d8b482c20b3d]::diagnostic_builder::DiagnosticBuilderInner as core[eee2e1d8d36d089]::ops::drop::Drop>::drop
   8:     0x7ff8cfbe3009 - <rustc_errors[a795d8b482c20b3d]::diagnostic_builder::DiagnosticBuilderInner as core[eee2e1d8d36d089]::ops::drop::Drop>::drop
   9:     0x7ff8cff29399 - rustc_query_system[a0b9f5f0299a8a38]::query::plumbing::incremental_verify_ich_cold
  10:     0x7ff8cfbd5629 - <rustc_feature[ea871e0fc9abb418]::builtin_attrs::AttributeType as core[eee2e1d8d36d089]::fmt::Debug>::fmt
  11:     0x7ff8cfbd9288 - <rustc_errors[a795d8b482c20b3d]::HandlerInner as core[eee2e1d8d36d089]::ops::drop::Drop>::drop
  12:     0x7ff8cb4a5794 - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  13:     0x7ff8cb4a8bca - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  14:     0x7ff8cb493ecd - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  15:     0x7ff8cb491bf9 - rustc_driver[dba66f49bbdf914a]::pretty::print_after_hir_lowering
  16:     0x7ff8cb42f540 - <rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::PtxLinker as rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::Linker>::no_default_libraries
  17:     0x7ff8cb432c27 - <rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::PtxLinker as rustc_codegen_ssa[a427f0aa3144ff71]::back::linker::Linker>::no_default_libraries
  18:     0x7ff8cb43c876 - <rustc_driver[dba66f49bbdf914a]::args::Error as core[eee2e1d8d36d089]::fmt::Debug>::fmt
  19:     0x7ff8cb43d998 - <rustc_driver[dba66f49bbdf914a]::args::Error as core[eee2e1d8d36d089]::fmt::Debug>::fmt
  20:     0x7ff8fe66edec - std::sys::windows::thread::Thread::new::h1883b00da4b4f517
  21:     0x7ff95ba97034 - BaseThreadInitThunk
  22:     0x7ff95d2a2651 - RtlUserThreadStart

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 1.62.0-nightly (6dd68402c 2022-05-11) running on x86_64-pc-windows-msvc

note: compiler flags: --crate-type bin -C embed-bitcode=no -C debuginfo=2 -C incremental

note: some of the compiler flags provided by cargo are hidden

query stack during panic:
end of query stack

[matthiaskrgr]

for the first example:

#![feature(adt_const_params, generic_const_exprs)]

pub struct Changes<const CHANGES: &'static [&'static str]>
where
    [(); CHANGES.len()]:,
{
    changes: [usize; CHANGES.len()],
}

impl<const CHANGES: &'static [&'static str]> Changes<CHANGES>
where
    [(); CHANGES.len()]:,
{
    pub const fn new() -> Self {
        Self {
            changes: [0; CHANGES.len()],
        }
    }
}

searched toolchains nightly-2021-12-01 through nightly-2022-05-12
Regression in nightly-2021-12-06

searched toolchains efec545293b9263be9edfb283a7aa66350b3acbf through e2116acae59654bfab2a9729a024f3e2fd6d4b02

Regression in 772d51f 🤔

EDIT: same for the second snippet.

[b-naber]

This is caused by #90529. Seems as if this issue takes care of this FIXME ^^.

Not sure what the right solution is, we originally tried to skip reborrows because implicit autorefs/autoderefs lead to confusing error messages given that we don't support derefs and refs in abstract consts. Maybe the right solution is to just clarify that autorefs/autoderefs happen there. Thoughts @lcnr?

[Alexendoo]

No longer ICEs since #98669 (perhaps due to #98499?)