univariant: field #2 comes after unsized field

[lylythechosenone]

Code

I'm not sure what exactly causes the ICE, but it happened in commit 0bb2479 on my fork of wgpu (lylythechosenone/wgpu).

Meta

rustc --version --verbose:

rustc 1.76.0 (07dca489a 2024-02-04)
binary: rustc
commit-hash: 07dca489ac2d933c78d3c5158e3f43beefeb02ce
commit-date: 2024-02-04
host: aarch64-apple-darwin
release: 1.76.0
LLVM version: 17.0.6

Error output

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

error: internal compiler error: univariant: field #2 comes after unsized field

Backtrace

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

error: internal compiler error: univariant: field #2 comes after unsized field
|
= note: delayed at compiler/rustc_middle/src/ty/layout.rs:286:23
           0: std::backtrace::Backtrace::create
           1: <rustc_errors::DiagCtxtInner>::emit_diagnostic_without_consuming
           2: <rustc_errors::DiagCtxtInner>::emit_diagnostic
           3: <rustc_errors::DiagCtxt>::span_delayed_bug::<rustc_span::span_encoding::Span, alloc::string::String>
           4: <rustc_middle::ty::layout::LayoutCx<rustc_middle::ty::context::TyCtxt> as rustc_abi::layout::LayoutCalculator>::delayed_bug
           5: rustc_abi::layout::univariant::<rustc_target::abi::FieldIdx, rustc_target::abi::VariantIdx, rustc_target::abi::Layout, rustc_middle::ty::layout::LayoutCx<rustc_middle::ty::context::TyCtxt>>
           6: <rustc_middle::ty::layout::LayoutCx<rustc_middle::ty::context::TyCtxt> as rustc_abi::layout::LayoutCalculator>::univariant::<rustc_target::abi::FieldIdx, rustc_target::abi::VariantIdx, rustc_target::abi::Layout>
           7: <rustc_middle::ty::layout::LayoutCx<rustc_middle::ty::context::TyCtxt> as rustc_abi::layout::LayoutCalculator>::layout_of_struct_or_enum::<rustc_target::abi::FieldIdx, rustc_target::abi::VariantIdx, rustc_target::abi::Layout, rustc_ty_utils::layout::layout_of_uncached::{closure#10}, core::iter::adapters::flatten::Flatten<core::option::IntoIter<core::iter::adapters::map::Map<core::iter::adapters::map::Map<core::iter::adapters::map::Map<core::iter::adapters::enumerate::Enumerate<core::slice::iter::Iter<rustc_middle::ty::VariantDef>>, <rustc_index::slice::IndexSlice<rustc_target::abi::VariantIdx, rustc_middle::ty::VariantDef>>::iter_enumerated::{closure#0}>, <rustc_middle::ty::adt::AdtDef>::discriminants::{closure#0}>, rustc_ty_utils::layout::layout_of_uncached::{closure#11}::{closure#0}::{closure#0}>>>>
           8: rustc_ty_utils::layout::layout_of_uncached
           9: rustc_ty_utils::layout::layout_of
          10: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::layout_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 16]>>
          11: <rustc_query_impl::query_impl::layout_of::dynamic_query::{closure#2} as core::ops::function::FnOnce<(rustc_middle::ty::context::TyCtxt, rustc_middle::ty::ParamEnvAnd<rustc_middle::ty::Ty>)>>::call_once
          12: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefaultCache<rustc_middle::ty::ParamEnvAnd<rustc_middle::ty::Ty>, rustc_middle::query::erase::Erased<[u8; 16]>>, false, true, false>, rustc_query_impl::plumbing::QueryCtxt, true>
          13: rustc_query_impl::query_impl::layout_of::get_query_incr::__rust_end_short_backtrace
          14: <rustc_middle::ty::layout::LayoutCx<rustc_middle::ty::context::TyCtxt> as rustc_middle::ty::layout::LayoutOf>::spanned_layout_of
          15: core::iter::adapters::try_process::<core::iter::adapters::by_ref_sized::ByRefSized<core::iter::adapters::map::Map<core::slice::iter::Iter<rustc_middle::ty::FieldDef>, rustc_ty_utils::layout::layout_of_uncached::{closure#8}::{closure#0}>>, rustc_target::abi::Layout, core::result::Result<core::convert::Infallible, &rustc_middle::ty::layout::LayoutError>, <core::iter::adapters::map::Map<core::slice::iter::Iter<rustc_middle::ty::FieldDef>, rustc_ty_utils::layout::layout_of_uncached::{closure#8}::{closure#0}> as core::iter::traits::iterator::Iterator>::try_collect<rustc_index::vec::IndexVec<rustc_target::abi::FieldIdx, rustc_target::abi::Layout>>::{closure#0}, rustc_index::vec::IndexVec<rustc_target::abi::FieldIdx, rustc_target::abi::Layout>>
          16: core::iter::adapters::try_process::<core::iter::adapters::by_ref_sized::ByRefSized<core::iter::adapters::map::Map<core::slice::iter::Iter<rustc_middle::ty::VariantDef>, rustc_ty_utils::layout::layout_of_uncached::{closure#8}>>, rustc_index::vec::IndexVec<rustc_target::abi::FieldIdx, rustc_target::abi::Layout>, core::result::Result<core::convert::Infallible, &rustc_middle::ty::layout::LayoutError>, <core::iter::adapters::map::Map<core::slice::iter::Iter<rustc_middle::ty::VariantDef>, rustc_ty_utils::layout::layout_of_uncached::{closure#8}> as core::iter::traits::iterator::Iterator>::try_collect<rustc_index::vec::IndexVec<rustc_target::abi::VariantIdx, rustc_index::vec::IndexVec<rustc_target::abi::FieldIdx, rustc_target::abi::Layout>>>::{closure#0}, rustc_index::vec::IndexVec<rustc_target::abi::VariantIdx, rustc_index::vec::IndexVec<rustc_target::abi::FieldIdx, rustc_target::abi::Layout>>>
          17: rustc_ty_utils::layout::layout_of_uncached
          18: rustc_ty_utils::layout::layout_of
          19: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::layout_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 16]>>
          20: <rustc_query_impl::query_impl::layout_of::dynamic_query::{closure#2} as core::ops::function::FnOnce<(rustc_middle::ty::context::TyCtxt, rustc_middle::ty::ParamEnvAnd<rustc_middle::ty::Ty>)>>::call_once
          21: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefaultCache<rustc_middle::ty::ParamEnvAnd<rustc_middle::ty::Ty>, rustc_middle::query::erase::Erased<[u8; 16]>>, false, true, false>, rustc_query_impl::plumbing::QueryCtxt, true>
          22: rustc_query_impl::query_impl::layout_of::get_query_incr::__rust_end_short_backtrace
          23: rustc_middle::query::plumbing::query_get_at::<rustc_query_system::query::caches::DefaultCache<rustc_middle::ty::ParamEnvAnd<rustc_middle::ty::Ty>, rustc_middle::query::erase::Erased<[u8; 16]>>>
          24: <rustc_mir_transform::const_prop::CanConstProp>::check
          25: <rustc_mir_transform::const_prop_lint::ConstPropLint as rustc_mir_transform::pass_manager::MirLint>::run_lint
          26: rustc_mir_transform::pass_manager::run_passes_inner
          27: rustc_mir_transform::run_analysis_to_runtime_passes
          28: rustc_mir_transform::mir_drops_elaborated_and_const_checked
          29: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_drops_elaborated_and_const_checked::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
          30: <rustc_query_impl::query_impl::mir_drops_elaborated_and_const_checked::dynamic_query::{closure#2} as core::ops::function::FnOnce<(rustc_middle::ty::context::TyCtxt, rustc_span::def_id::LocalDefId)>>::call_once
          31: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, true>
          32: rustc_query_impl::query_impl::mir_drops_elaborated_and_const_checked::get_query_incr::__rust_end_short_backtrace
          33: rustc_mir_transform::optimized_mir
          34: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::optimized_mir::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
          35: <rustc_query_impl::query_impl::optimized_mir::dynamic_query::{closure#2} as core::ops::function::FnOnce<(rustc_middle::ty::context::TyCtxt, rustc_span::def_id::DefId)>>::call_once
          36: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefaultCache<rustc_span::def_id::DefId, rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, true>
          37: rustc_query_impl::query_impl::optimized_mir::get_query_incr::__rust_end_short_backtrace
          38: rustc_middle::query::plumbing::query_get_at::<rustc_query_system::query::caches::DefaultCache<rustc_span::def_id::DefId, rustc_middle::query::erase::Erased<[u8; 8]>>>
          39: <clippy_lints::redundant_clone::RedundantClone as rustc_lint::passes::LateLintPass>::check_fn
          40: rustc_hir::intravisit::walk_impl_item::<rustc_lint::late::LateContextAndPass<rustc_lint::late::RuntimeCombinedLateLintPass>>
          41: <rustc_lint::late::LateContextAndPass<rustc_lint::late::RuntimeCombinedLateLintPass> as rustc_hir::intravisit::Visitor>::visit_nested_impl_item
          42: rustc_hir::intravisit::walk_item::<rustc_lint::late::LateContextAndPass<rustc_lint::late::RuntimeCombinedLateLintPass>>
          43: <rustc_lint::late::LateContextAndPass<rustc_lint::late::RuntimeCombinedLateLintPass> as rustc_hir::intravisit::Visitor>::visit_nested_item
          44: rustc_hir::intravisit::walk_item::<rustc_lint::late::LateContextAndPass<rustc_lint::late::RuntimeCombinedLateLintPass>>
          45: <rustc_lint::late::LateContextAndPass<rustc_lint::late::RuntimeCombinedLateLintPass> as rustc_hir::intravisit::Visitor>::visit_nested_item
          46: rustc_lint::late::late_lint_crate
          47: <rustc_session::session::Session>::time::<(), rustc_lint::late::check_crate::{closure#0}::{closure#0}>
          48: <rustc_data_structures::sync::parallel::ParallelGuard>::run::<(), rustc_lint::late::check_crate::{closure#0}>
          49: rustc_data_structures::sync::parallel::disabled::join::<rustc_lint::late::check_crate::{closure#0}, rustc_lint::late::check_crate::{closure#1}, (), ()>
          50: rustc_lint::late::check_crate
          51: <rustc_session::session::Session>::time::<(), rustc_interface::passes::analysis::{closure#6}::{closure#1}::{closure#0}::{closure#0}::{closure#2}::{closure#0}>
          52: <rustc_data_structures::sync::parallel::ParallelGuard>::run::<(), rustc_interface::passes::analysis::{closure#6}::{closure#1}::{closure#0}::{closure#0}::{closure#2}>
          53: std::panicking::try::<(), core::panic::unwind_safe::AssertUnwindSafe<rustc_interface::passes::analysis::{closure#6}::{closure#1}::{closure#0}>>
          54: <rustc_data_structures::sync::parallel::ParallelGuard>::run::<(), rustc_interface::passes::analysis::{closure#6}::{closure#1}::{closure#0}>
          55: <rustc_session::session::Session>::time::<(), rustc_interface::passes::analysis::{closure#6}>
          56: rustc_interface::passes::analysis
          57: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
          58: <rustc_query_impl::query_impl::analysis::dynamic_query::{closure#2} as core::ops::function::FnOnce<(rustc_middle::ty::context::TyCtxt, ())>>::call_once
          59: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 1]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, true>
          60: rustc_query_impl::query_impl::analysis::get_query_incr::__rust_end_short_backtrace
          61: <rustc_middle::ty::context::GlobalCtxt>::enter::<rustc_driver_impl::run_compiler::{closure#0}::{closure#0}::{closure#3}, core::result::Result<(), rustc_span::ErrorGuaranteed>>
          62: <rustc_interface::interface::Compiler>::enter::<rustc_driver_impl::run_compiler::{closure#0}::{closure#0}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>
          63: rustc_span::create_session_globals_then::<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}>
          64: std::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface::util::run_in_thread_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>
          65: <<std::thread::Builder>::spawn_unchecked_<rustc_interface::util::run_in_thread_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
          66: std::sys::unix::thread::Thread::new::thread_start
          67: __pthread_joiner_wake
        

note: we would appreciate a bug report: https://github.com/rust-lang/rust-clippy/issues/new?template=ice.yml

note: rustc 1.76.0 (07dca489a 2024-02-04) running on aarch64-apple-darwin

note: compiler flags: --crate-type lib -C embed-bitcode=no -C debuginfo=2 -C split-debuginfo=unpacked -C incremental=[REDACTED]

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

query stack during panic:
end of query stack
note: Clippy version: clippy 0.1.76 (07dca489 2024-02-04)

note: we would appreciate a bug report: https://github.com/rust-lang/rust-clippy/issues/new?template=ice.yml

note: rustc 1.76.0 (07dca489a 2024-02-04) running on aarch64-apple-darwin

note: compiler flags: -C embed-bitcode=no -C debuginfo=2 -C split-debuginfo=unpacked -C incremental=[REDACTED]

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

query stack during panic:
end of query stack
note: Clippy version: clippy 0.1.76 (07dca489 2024-02-04)

[lylythechosenone]

@compiler-errors I'm not really sure how to minimize it. Currently, I have no idea which struct is causing the error, nor why. I have tried using cargo-minimize, but it did do very much at all. Let me know if there's something else I should try.

P.S. the scope of the changes isn't too huge, and I'm 100% sure that the issue relates to the new ?Sized bounds on Api types.

[jieyouxu]

ERROR rustc_abi::layout dl=TargetDataLayout { endian: little, i1_align: AbiAndPrefAlign { abi: Align(1 bytes), pref: Align(1 bytes) }, i8_align: AbiAndPrefAlign { abi: Align(1 bytes), pref: Align(1 bytes) }, i16_align: AbiAndPrefAlign { abi: Align(2 bytes), pref: Align(2 bytes) }, i32_align: AbiAndPrefAlign { abi: Align(4 bytes), pref: Align(4 bytes) }, i64_align: AbiAndPrefAlign { abi: Align(8 bytes), pref: Align(8 bytes) }, i128_align: AbiAndPrefAlign { abi: Align(16 bytes), pref: Align(16 bytes) }, f16_align: AbiAndPrefAlign { abi: Align(2 bytes), pref: Align(2 bytes) }, f32_align: AbiAndPrefAlign { abi: Align(4 bytes), pref: Align(4 bytes) }, f64_align: AbiAndPrefAlign { abi: Align(8 bytes), pref: Align(8 bytes) }, f128_align: AbiAndPrefAlign { abi: Align(16 bytes), pref: Align(16 bytes) }, pointer_size: Size(8 bytes), pointer_align: AbiAndPrefAlign { abi: Align(8 bytes), pref: Align(8 bytes) }, aggregate_align: AbiAndPrefAlign { abi: Align(1 bytes), pref: Align(8 bytes) }, vector_align: [(Size(8 bytes), AbiAndPrefAlign { abi: Align(8 bytes), pref: Align(8 bytes) }), (Size(16 bytes), AbiAndPrefAlign { abi: Align(16 bytes), pref: Align(16 bytes) })], instruction_address_space: AddressSpace(0), c_enum_min_size: I32 }, fields=[Layout { size: Size(0 bytes), align: AbiAndPrefAlign { abi: Align(1 bytes), pref: Align(8 bytes) }, abi: Aggregate { sized: false }, fields: Arbitrary { offsets: [], memory_index: [] }, largest_niche: None, variants: Single { index: 0 }, max_repr_align: None, unadjusted_abi_align: Align(1 bytes) }, Layout { size: Size(0 bytes), align: AbiAndPrefAlign { abi: Align(1 bytes), pref: Align(8 bytes) }, abi: Aggregate { sized: false }, fields: Arbitrary { offsets: [], memory_index: [] }, largest_niche: None, variants: Single { index: 0 }, max_repr_align: None, unadjusted_abi_align: Align(1 bytes) }], repr=ReprOptions { int: None, align: None, pack: None, flags: , field_shuffle_seed: 779237850841490393 }, kind=AlwaysSized
note: no errors encountered even though delayed bugs were created

note: those delayed bugs will now be shown as internal compiler errors

error: internal compiler error: univariant: field #2 comes after unsized field

[lylythechosenone]

Alright I may have actually just found it. It seems like it's in this struct:

pub struct OpenDevice<A: Api>
where
    A::Device: Sized,
    A::Queue: Sized,
{
    pub device: A::Device,
    pub queue: A::Queue,
}

[lukas-code]

Here is a self-contained reproducer, can probably be minimized further: playground link

trait Api: Sized {
    type Device: ?Sized;
}

struct OpenDevice<A: Api>
where
    A::Device: Sized,
{
    device: A::Device,
    queue: (),
}

trait Adapter {
    type A: Api;

    fn open() -> OpenDevice<Self::A>
    where
        <Self::A as Api>::Device: Sized;
}

struct ApiS;

impl Api for ApiS {
    type Device = [u8];
}

impl<T> Adapter for T {
    type A = ApiS;

    fn open() -> OpenDevice<Self::A>
    where
        <Self::A as Api>::Device: Sized,
    {
        unreachable!()
    }
}

[lylythechosenone]

@lukas-code thank you very much. I was gone else I would've done that myself 😅.

[matthiaskrgr]

Regression in nightly-2023-08-30
looking for regression commit between 2023-08-29 and 2023-08-30
fetching (via remote github) commits from max(4e78abb, 2023-08-27) to 84a9f4c
ending github query because we found starting sha: 4e78abb
get_commits_between returning commits, len: 13
commit[0] 2023-08-28: Auto merge of #115326 - matthiaskrgr:rollup-qsoa8ar, r=matthiaskrgr
commit[1] 2023-08-28: Auto merge of #115182 - RalfJung:abi-compat-sign, r=b-naber
commit[2] 2023-08-29: Auto merge of #115309 - hermitcore:hermit-net-init, r=cuviper
commit[3] 2023-08-29: Auto merge of #115260 - scottmcm:not-quite-so-cold, r=WaffleLapkin
commit[4] 2023-08-29: Auto merge of #115312 - hermitcore:hermit-is_interrupted, r=thomcc
commit[5] 2023-08-29: Auto merge of #113859 - Manishearth:vec-as-mut-ptr-stacked-borrow, r=dtolnay
commit[6] 2023-08-29: Auto merge of #114795 - RalfJung:cell-swap, r=dtolnay
commit[7] 2023-08-29: Auto merge of #115277 - RalfJung:is_1zst, r=davidtwco
commit[8] 2023-08-29: Auto merge of #114894 - Zoxc:sharded-cfg-cleanup2, r=cjgillot
commit[9] 2023-08-29: Auto merge of #112775 - c410-f3r:t3st3ss, r=petrochenkov
commit[10] 2023-08-29: Auto merge of #115183 - flip1995:clippyup, r=Manishearth,oli-obk
commit[11] 2023-08-29: Auto merge of #115354 - matthiaskrgr:rollup-4cotcxz, r=matthiaskrgr
commit[12] 2023-08-29: Auto merge of #114114 - keith:ks/always-add-lc_build_version-for-metadata-object-files, r=wesleywiser
ERROR: no CI builds available between 4e78abb and 84a9f4c within last 167 days