Compiler crash: 'assertion failed: self.scc_universes[scc] == ty::UniverseIndex::ROOT'

[danheuck]

This appears to be the same assertion as #100818, #97099, and #103186 (though I'm unclear if the cause is the same) occurring on both stable rust 1.65.0 and nightly 1.67.0. The below reproduction is as minimal as I could get it. Worth noting that I don't believe this code would compile even without the ICE.

Code

use core::future::Future;

pub struct Struct<C, Fu, F>
where
    F: Fn(&C) -> Fu,
    Fu: Future,
{
    handler: F,
    context: C,
}

impl<C, Fu, R, F> Struct<C, Fu, F>
where
    F: Fn(&C) -> Fu,
    Fu: Future<Output = R>,
{
    pub const fn new(handler: F, context: C) -> Self {
        Self { handler, context }
    }
}

type TestC = &'static usize;
type TestFu = impl Future;
type TestF = impl Fn(&TestC) -> TestFu;
type TestStruct = Struct<TestC, TestFu, TestF>;

async fn test_handler(context: &TestC) -> () {
    ()
}

fn get_test_struct() -> &'static TestStruct {
    static test_actor: TestStruct = TestStruct::new(test_handler, &0);
    &test_actor
}

Meta

rustc --version --verbose:

rustc 1.65.0 (897e37553 2022-11-02)
binary: rustc
commit-hash: 897e37553bba8b42751c67658967889d11ecd120
commit-date: 2022-11-02
host: x86_64-pc-windows-msvc
release: 1.65.0
LLVM version: 15.0.0

Error output

thread 'rustc' panicked at 'assertion failed: self.scc_universes[scc] == ty::UniverseIndex::ROOT', compiler\rustc_borrowck\src\region_infer\mod.rs:721:9

Backtrace

stack backtrace:
   0:     0x7ffa62ca8fb2 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h1086ecfa86360858
   1:     0x7ffa62ce40db - core::fmt::write::hbadbc3de7beb6abb
   2:     0x7ffa62c9b8aa - <std::io::IoSlice as core::fmt::Debug>::fmt::hb7e33fb242ec9ac1
   3:     0x7ffa62cac5b4 - std::panicking::default_hook::hb8b3ce065b661264
   4:     0x7ffa62cac1ea - std::panicking::default_hook::hb8b3ce065b661264
   5:     0x7ffa3abe25ee - rustc_driver[c6471a3a75cc3305]::describe_lints
   6:     0x7ffa62cacfb2 - std::panicking::rust_panic_with_hook::h33e40e3f5d3be1f3
   7:     0x7ffa62caccfa - <std::panicking::begin_panic_handler::StrPanicPayload as core::panic::BoxMeUp>::get::h5aceb4e60531e534
   8:     0x7ffa62ca9cbf - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h1086ecfa86360858
   9:     0x7ffa62caca00 - rust_begin_unwind
  10:     0x7ffa62d19905 - core::panicking::panic_fmt::h0af4781e6a0c54d3
  11:     0x7ffa62d197ac - core::panicking::panic::hd1f6d7a0e46f29da
  12:     0x7ffa3a3f7435 - <rustc_infer[3acbbff32055c339]::infer::InferCtxt as rustc_borrowck[7ffb48d475d38a4e]::universal_regions::InferCtxtExt>::replace_late_bound_regions_with_nll_infer_vars
  13:     0x7ffa3a3ea95e - <rustc_borrowck[7ffb48d475d38a4e]::constraints::OutlivesConstraintSet as core[8087a2e8d825f5e1]::ops::index::Index<rustc_borrowck[7ffb48d475d38a4e]::constraints::OutlivesConstraintIndex>>::index
  14:     0x7ffa3a2e31a8 - <rustc_middle[12c473a188441910]::ty::adjustment::AutoBorrowMutability as rustc_mir_build[236c88af9e57eadb]::thir::cx::expr::ToBorrowKind>::to_borrow_kind
  15:     0x7ffa3a2db836 - <rustc_middle[12c473a188441910]::ty::adjustment::AutoBorrowMutability as rustc_mir_build[236c88af9e57eadb]::thir::cx::expr::ToBorrowKind>::to_borrow_kind
  16:     0x7ffa3a2dae38 - <rustc_middle[12c473a188441910]::ty::adjustment::AutoBorrowMutability as rustc_mir_build[236c88af9e57eadb]::thir::cx::expr::ToBorrowKind>::to_borrow_kind
  17:     0x7ffa38f76ba8 - <rustc_query_impl[9648f954f060bbf5]::queries::is_reachable_non_generic as rustc_query_system[658c00a88212f6cf]::query::config::QueryDescription<rustc_query_impl[9648f954f060bbf5]::plumbing::QueryCtxt>>::execute_query
  18:     0x7ffa390cffbe - <&[rustc_type_ir[1421f89e31f06786]::Variance] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode  
  19:     0x7ffa3a60b7a3 - <&[(rustc_middle[12c473a188441910]::ty::Predicate, rustc_span[335b190b38ec46cb]::span_encoding::Span)] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode
  20:     0x7ffa3a54a875 - <rustc_query_impl[9648f954f060bbf5]::Queries as rustc_middle[12c473a188441910]::ty::query::QueryEngine>::as_any
  21:     0x7ffa3c24ad66 - <rustc_typeck[49c87e7593e195a8]::collect::type_of::find_opaque_ty_constraints_for_tait::ConstraintLocator as rustc_hir[fcc301f55e55bb6a]::intravisit::Visitor>::visit_trait_item    
  22:     0x7ffa3c23da23 - <rustc_typeck[49c87e7593e195a8]::check::method::suggest::SelfSource as core[8087a2e8d825f5e1]::fmt::Debug>::fmt
  23:     0x7ffa3c2c7f7b - <rustc_typeck[49c87e7593e195a8]::check::upvar::MigrationWarningReason as core[8087a2e8d825f5e1]::fmt::Debug>::fmt
  24:     0x7ffa3c23d9e3 - <rustc_typeck[49c87e7593e195a8]::check::method::suggest::SelfSource as core[8087a2e8d825f5e1]::fmt::Debug>::fmt
  25:     0x7ffa3c2d0048 - <rustc_typeck[49c87e7593e195a8]::check::upvar::MigrationWarningReason as core[8087a2e8d825f5e1]::fmt::Debug>::fmt
  26:     0x7ffa3c23da2e - <rustc_typeck[49c87e7593e195a8]::check::method::suggest::SelfSource as core[8087a2e8d825f5e1]::fmt::Debug>::fmt
  27:     0x7ffa3c2cc649 - <rustc_typeck[49c87e7593e195a8]::check::upvar::MigrationWarningReason as core[8087a2e8d825f5e1]::fmt::Debug>::fmt
  28:     0x7ffa3c24a5c9 - <rustc_typeck[49c87e7593e195a8]::check::PlaceOp as core[8087a2e8d825f5e1]::fmt::Debug>::fmt
  29:     0x7ffa3a116700 - <rustc_typeck[49c87e7593e195a8]::check::UnsafetyState>::recurse
  30:     0x7ffa3a69f389 - <&[(rustc_middle[12c473a188441910]::ty::Predicate, rustc_span[335b190b38ec46cb]::span_encoding::Span)] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode
  31:     0x7ffa3a67c76a - <&[(rustc_middle[12c473a188441910]::ty::Predicate, rustc_span[335b190b38ec46cb]::span_encoding::Span)] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode
  32:     0x7ffa3aaae51c - <rustc_middle[12c473a188441910]::ty::context::TyCtxt>::bound_type_of
  33:     0x7ffa3a9508d0 - <rustc_trait_selection[51ac1f8d3e2d292c]::traits::select::SelectionContext>::evaluate_root_obligation
  34:     0x7ffa3a936ad6 - <rustc_trait_selection[51ac1f8d3e2d292c]::traits::select::SelectionContext>::evaluate_root_obligation
  35:     0x7ffa3a95dadb - <rustc_trait_selection[51ac1f8d3e2d292c]::traits::select::SelectionContext>::select
  36:     0x7ffa3a936bf5 - <rustc_trait_selection[51ac1f8d3e2d292c]::traits::select::SelectionContext>::evaluate_root_obligation
  37:     0x7ffa3a95dadb - <rustc_trait_selection[51ac1f8d3e2d292c]::traits::select::SelectionContext>::select
  38:     0x7ffa3a9359ca - <rustc_trait_selection[51ac1f8d3e2d292c]::traits::select::SelectionContext>::evaluate_root_obligation
  39:     0x7ffa3a41f836 - <regex[c10d5b7862cb2dbf]::re_bytes::CaptureNames as core[8087a2e8d825f5e1]::iter::traits::iterator::Iterator>::size_hint
  40:     0x7ffa3a40b925 - <rustc_infer[3acbbff32055c339]::infer::InferCtxt as rustc_borrowck[7ffb48d475d38a4e]::universal_regions::InferCtxtExt>::replace_late_bound_regions_with_nll_infer_vars
  41:     0x7ffa3a6953d2 - <&[(rustc_middle[12c473a188441910]::ty::Predicate, rustc_span[335b190b38ec46cb]::span_encoding::Span)] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode
  42:     0x7ffa3a668608 - <&[(rustc_middle[12c473a188441910]::ty::Predicate, rustc_span[335b190b38ec46cb]::span_encoding::Span)] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode
  43:     0x7ffa3a54f9a6 - <rustc_query_impl[9648f954f060bbf5]::Queries as rustc_middle[12c473a188441910]::ty::query::QueryEngine>::as_any
  44:     0x7ffa3a916be1 - <rustc_trait_selection[51ac1f8d3e2d292c]::traits::fulfill::FulfillProcessor as rustc_data_structures[1b20f7c7eb90dc04]::obligation_forest::ObligationProcessor>::process_obligation 
  45:     0x7ffa3a9c6f9f - <rustc_middle[12c473a188441910]::ty::Predicate as rustc_trait_selection[51ac1f8d3e2d292c]::traits::query::type_op::normalize::Normalizable>::type_op_method
  46:     0x7ffa3a90cc4b - <rustc_trait_selection[51ac1f8d3e2d292c]::traits::engine::ObligationCtxt>::select_all_or_error
  47:     0x7ffa38d4f3ca - <rustc_typeck[49c87e7593e195a8]::expr_use_visitor::ExprUseVisitor>::consume_body
  48:     0x7ffa38d2db00 - <<rustc_typeck[49c87e7593e195a8]::check::method::confirm::ConfirmContext>::instantiate_method_substs::MethodSubstsCtxt as rustc_typeck[49c87e7593e195a8]::astconv::CreateSubstsForGenericArgsCtxt>::inferred_kind
  49:     0x7ffa39fe4bc3 - <<rustc_typeck[49c87e7593e195a8]::check::method::confirm::ConfirmContext>::instantiate_method_substs::MethodSubstsCtxt as rustc_typeck[49c87e7593e195a8]::astconv::CreateSubstsForGenericArgsCtxt>::args_for_def_id
  50:     0x7ffa38f75a98 - <rustc_query_impl[9648f954f060bbf5]::queries::is_reachable_non_generic as rustc_query_system[658c00a88212f6cf]::query::config::QueryDescription<rustc_query_impl[9648f954f060bbf5]::plumbing::QueryCtxt>>::execute_query
  51:     0x7ffa390d3a9e - <&[rustc_type_ir[1421f89e31f06786]::Variance] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode  
  52:     0x7ffa3a61066a - <&[(rustc_middle[12c473a188441910]::ty::Predicate, rustc_span[335b190b38ec46cb]::span_encoding::Span)] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode
  53:     0x7ffa3a54e0c8 - <rustc_query_impl[9648f954f060bbf5]::Queries as rustc_middle[12c473a188441910]::ty::query::QueryEngine>::as_any
  54:     0x7ffa3a11b89f - rustc_typeck[49c87e7593e195a8]::check::rvalue_scopes::resolve_rvalue_scopes
  55:     0x7ffa38d2f6f5 - <<rustc_typeck[49c87e7593e195a8]::check::method::confirm::ConfirmContext>::instantiate_method_substs::MethodSubstsCtxt as rustc_typeck[49c87e7593e195a8]::astconv::CreateSubstsForGenericArgsCtxt>::inferred_kind
  56:     0x7ffa38f75a98 - <rustc_query_impl[9648f954f060bbf5]::queries::is_reachable_non_generic as rustc_query_system[658c00a88212f6cf]::query::config::QueryDescription<rustc_query_impl[9648f954f060bbf5]::plumbing::QueryCtxt>>::execute_query
  57:     0x7ffa390d3a9e - <&[rustc_type_ir[1421f89e31f06786]::Variance] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode  
  58:     0x7ffa3a61066a - <&[(rustc_middle[12c473a188441910]::ty::Predicate, rustc_span[335b190b38ec46cb]::span_encoding::Span)] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode
  59:     0x7ffa390b89bc - <&[rustc_type_ir[1421f89e31f06786]::Variance] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode  
  60:     0x7ffa38d9b975 - <rustc_typeck[49c87e7593e195a8]::check::cast::CastCheck>::check
  61:     0x7ffa38dab74b - rustc_typeck[49c87e7593e195a8]::check::dropck::check_drop_impl
  62:     0x7ffa38d8848a - <rustc_typeck[49c87e7593e195a8]::check::fn_ctxt::FnCtxt>::write_user_type_annotation
  63:     0x7ffa38d34819 - rustc_typeck[49c87e7593e195a8]::check_crate
  64:     0x7ffa3945a63f - rustc_interface[9c167b8dd5fe1201]::passes::analysis
  65:     0x7ffa38f7830e - <rustc_query_impl[9648f954f060bbf5]::queries::is_reachable_non_generic as rustc_query_system[658c00a88212f6cf]::query::config::QueryDescription<rustc_query_impl[9648f954f060bbf5]::plumbing::QueryCtxt>>::execute_query
  66:     0x7ffa390ed9c3 - <&[rustc_type_ir[1421f89e31f06786]::Variance] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode  
  67:     0x7ffa39070ca7 - <&[rustc_type_ir[1421f89e31f06786]::Variance] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode  
  68:     0x7ffa390c10b6 - <&[rustc_type_ir[1421f89e31f06786]::Variance] as rustc_serialize[5ba6e6ef117c5717]::serialize::Decodable<rustc_query_impl[9648f954f060bbf5]::on_disk_cache::CacheDecoder>>::decode  
  69:     0x7ffa3855c9d9 - rustc_driver[c6471a3a75cc3305]::args::arg_expand_all
  70:     0x7ffa3852a3a8 - rustc_driver[c6471a3a75cc3305]::main
  71:     0x7ffa3855e32a - <rustc_middle[12c473a188441910]::ty::SymbolName as core[8087a2e8d825f5e1]::fmt::Debug>::fmt
  72:     0x7ffa38545e60 - rustc_driver[c6471a3a75cc3305]::main
  73:     0x7ffa3855d7d7 - <rustc_middle[12c473a188441910]::ty::SymbolName as core[8087a2e8d825f5e1]::fmt::Debug>::fmt
  74:     0x7ffa3854e109 - rustc_driver[c6471a3a75cc3305]::main
  75:     0x7ffa3854e56d - rustc_driver[c6471a3a75cc3305]::main
  76:     0x7ffa62cbd7cc - std::sys::windows::thread::Thread::new::h742bb0c6405f02e2
  77:     0x7ffb262b7034 - BaseThreadInitThunk
  78:     0x7ffb27c826a1 - RtlUserThreadStart

error: internal compiler error: unexpected panic

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 1.65.0 (897e37553 2022-11-02) running on x86_64-pc-windows-msvc

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

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

query stack during panic:
#0 [mir_borrowck] borrow-checking `get_test_struct::test_actor`
#1 [type_of] computing type of `TestF::{opaque#0}`
#2 [evaluate_obligation] evaluating trait selection obligation `Struct<&'static usize, TestFu, TestF>: core::marker::Sync`
#3 [check_well_formed] checking that `get_test_struct::test_actor` is well-formed
#4 [check_mod_type_wf] checking that types are well-formed in top-level module
#5 [analysis] running analysis passes on this crate
end of query stack