[ICE]: opaque type with non-universal region args

[BloodStainedCrow]

Code

pub fn get_all_files_in_dir<'async_recursion>() ->  core::pin::Pin<Box<dyn ::core::future::Future<Output = impl IntoIterator<Item = u32>> + 'async_recursion>> {
    Box::pin(async move {
        let response = vec![];
        let x = response.into_iter();
        let y = get_all_files_in_dir().await;
        let res = if true {
            x
        } else {
            y
        };
        res
    })
}

Affected release channels

• Previous Stable
• Current Stable
• Current Beta
• Current Nightly

Rust Version

$ rustc --version --verbose
rustc 1.78.0 (9b00956e5 2024-04-29)
binary: rustc
commit-hash: 9b00956e56009bab2aa15d7bff10916599e3d6d6
commit-date: 2024-04-29
host: x86_64-unknown-linux-gnu
release: 1.78.0
LLVM version: 18.1.2

Current error output

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: opaque type with non-universal region args

Backtrace

error: internal compiler error: opaque type with non-universal region args
  --> test_ICE/src/main.rs:11:13
   |
11 |             y
   |             ^
   |
note: delayed at compiler/rustc_borrowck/src/region_infer/opaque_types.rs:97:25
         0: <rustc_errors::DiagCtxtInner>::emit_diagnostic
         1: <rustc_errors::DiagCtxt>::emit_diagnostic
         2: <rustc_span::ErrorGuaranteed as rustc_errors::diagnostic::EmissionGuarantee>::emit_producing_guarantee
         3: <rustc_borrowck::region_infer::RegionInferenceContext>::infer_opaque_types::{closure#0}::{closure#1}.cold
         4: <&rustc_middle::ty::list::List<rustc_middle::ty::generic_args::GenericArg> as rustc_type_ir::fold::TypeFoldable<rustc_middle::ty::context::TyCtxt>>::try_fold_with::<rustc_middle::ty::fold::RegionFolder>
         5: rustc_borrowck::nll::compute_regions
         6: rustc_borrowck::do_mir_borrowck
         7: rustc_borrowck::mir_borrowck
         8: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_borrowck::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
         9: 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>
        10: rustc_query_impl::query_impl::mir_borrowck::get_query_incr::__rust_end_short_backtrace
        11: <rustc_borrowck::type_check::TypeChecker>::prove_closure_bounds
        12: <rustc_borrowck::type_check::TypeChecker>::typeck_mir
        13: rustc_borrowck::type_check::type_check
        14: rustc_borrowck::nll::compute_regions
        15: rustc_borrowck::do_mir_borrowck
        16: rustc_borrowck::mir_borrowck
        17: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::mir_borrowck::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
        18: 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>
        19: rustc_query_impl::query_impl::mir_borrowck::get_query_incr::__rust_end_short_backtrace
        20: rustc_hir_analysis::collect::type_of::type_of_opaque
        21: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::type_of_opaque::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
        22: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefIdCache<rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, true>
        23: rustc_query_impl::query_impl::type_of_opaque::get_query_incr::__rust_end_short_backtrace
        24: rustc_hir_analysis::collect::type_of::type_of
        25: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::type_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 8]>>
        26: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefIdCache<rustc_middle::query::erase::Erased<[u8; 8]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, true>
        27: rustc_query_impl::query_impl::type_of::get_query_incr::__rust_end_short_backtrace
        28: rustc_hir_analysis::check::check::check_item_type
        29: rustc_hir_analysis::check::wfcheck::check_well_formed
        30: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_well_formed::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
        31: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::VecCache<rustc_hir::hir_id::OwnerId, rustc_middle::query::erase::Erased<[u8; 1]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, true>
        32: rustc_query_impl::query_impl::check_well_formed::get_query_incr::__rust_end_short_backtrace
        33: rustc_hir_analysis::check::wfcheck::check_mod_type_wf
        34: rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::check_mod_type_wf::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 1]>>
        35: rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::DefaultCache<rustc_span::def_id::LocalModDefId, rustc_middle::query::erase::Erased<[u8; 1]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, true>
        36: rustc_query_impl::query_impl::check_mod_type_wf::get_query_incr::__rust_end_short_backtrace
        37: rustc_hir_analysis::check_crate
        38: rustc_interface::passes::analysis
        39: 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]>>
        40: 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>
        41: rustc_query_impl::query_impl::analysis::get_query_incr::__rust_end_short_backtrace
        42: rustc_interface::interface::run_compiler::<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}
        43: 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>>
        44: <<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}
        45: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
                   at /rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/alloc/src/boxed.rs:2020:9
        46: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
                   at /rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/alloc/src/boxed.rs:2020:9
        47: std::sys::pal::unix::thread::Thread::new::thread_start
                   at /rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/sys/pal/unix/thread.rs:108:17
        48: <unknown>
        49: <unknown>
  --> test_ICE/src/main.rs:11:13
   |
11 |             y
   |             ^

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 1.78.0 (9b00956e5 2024-04-29) running on x86_64-unknown-linux-gnu

note: compiler flags: --crate-type bin -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:
end of query stack

Anything else?

The problem does not appear if the lifetime parameter is removed

[lqd]

As you've noticed, this does not happen on nightly and beta. This issue is a duplicate of #111906, and has already been fixed by PR #116891. That PR will land on stable 1.79 next month.

I'll close this as a duplicate then. Thanks for opening an issue!