Assertion during ArgusCallbacks::after_expansion()

[djc]

Problem

Encountered this while working on https://github.com/KumoCorp/kumomta, in this branch. (I think this is the one I was mentioning earlier in my conversation with @gavinleroy.)

Logs

OS: darwin (24.0.0)
VSCode: 1.93.1
Error message

[INFO src/plugin.rs:238] - Starting rustc analysis...
[INFO src/timer.rs:8] - rustc took 0.0206s
[INFO src/timer.rs:8] - global_ctxt took 0.0000s
[INFO src/find_bodies.rs:52] - Starting find_bodies...
[INFO src/timer.rs:8] - find_bodies took 0.0028s
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:109 ~ kumo_spf[8991]::record::starts_with_number).13) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:109 ~ kumo_spf[8991]::record::starts_with_number).26) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:109 ~ kumo_spf[8991]::record::starts_with_number).69) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:109 ~ kumo_spf[8991]::record::starts_with_number).146) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:113 ~ kumo_spf[8991]::record::starts_with_ident).60) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:129 ~ kumo_spf[8991]::record::{impl#9}::parse::add_literal).44) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:130 ~ kumo_spf[8991]::record::{impl#9}::parse::is_macro_literal).31) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:167 ~ kumo_spf[8991]::record::{impl#13}::fmt).23) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:87 ~ kumo_spf[8991]::record::{impl#0}::parse).30) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:87 ~ kumo_spf[8991]::record::{impl#0}::parse).243) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:89 ~ kumo_spf[8991]::record::{impl#0}::evaluate).158) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:89 ~ kumo_spf[8991]::record::{impl#0}::evaluate).159) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:176 ~ kumo_spf[8991]::record::{impl#14}::fmt).47) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:181 ~ kumo_spf[8991]::record::{impl#15}::fmt).28) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:92 ~ kumo_spf[8991]::record::{impl#1}::parse).93) }
[INFO src/plugin.rs:315] - analyzing BodyId { hir_id: HirId(DefId(0:93 ~ kumo_spf[8991]::record::{impl#1}::evaluate).307) }
thread 'rustc' panicked at compiler/rustc_infer/src/infer/opaque_types/mod.rs:497:9:
assertion `left == right` failed
  left: Some(?4t)
 right: None
stack backtrace:
   0: _rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::panicking::assert_failed_inner
   3: core::panicking::assert_failed::<core::option::Option<rustc_middle::ty::Ty>, core::option::Option<rustc_middle::ty::Ty>>
   4: <rustc_trait_selection::solve::eval_ctxt::EvalCtxt>::evaluate_goal_raw
   5: <rustc_trait_selection::solve::eval_ctxt::EvalCtxt>::enter_root::<core::result::Result<(bool, rustc_type_ir::solve::Certainty), rustc_type_ir::solve::NoSolution>, <rustc_infer::infer::InferCtxt as rustc_trait_selection::solve::eval_ctxt::InferCtxtEvalExt>::evaluate_root_goal::{closure#0}>
   6: <rustc_trait_selection::solve::fulfill::FulfillmentCtxt as rustc_infer::traits::engine::TraitEngine>::select_where_possible
   7: <rustc_hir_typeck::fn_ctxt::FnCtxt>::type_inference_fallback
   8: rustc_hir_typeck::typeck
      [... omitted 2 frames ...]
   9: rustc_middle::query::plumbing::query_get_at::<rustc_query_system::query::caches::VecCache<rustc_span::def_id::LocalDefId, rustc_middle::query::erase::Erased<[u8; 8]>>>
  10: rustc_hir_typeck::inspect_typeck
  11: argus_lib::analysis::obligations
  12: <argus_cli::plugin::ArgusCallbacks<A,T,F> as rustc_driver_impl::Callbacks>::after_expansion::{{closure}}::{{closure}}
  13: alloc::vec::in_place_collect::<impl alloc::vec::spec_from_iter::SpecFromIter<T,I> for alloc::vec::Vec<T>>::from_iter
  14: rustc_middle::ty::context::GlobalCtxt::enter
  15: <argus_cli::plugin::ArgusCallbacks<A,T,F> as rustc_driver_impl::Callbacks>::after_expansion
  16: <rustc_interface::interface::Compiler>::enter::<rustc_driver_impl::run_compiler::{closure#0}::{closure#1}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>
  17: <scoped_tls::ScopedKey<rustc_span::SessionGlobals>>::set::<rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}::{closure#0}::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>
  18: rustc_span::create_session_globals_then::<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_interface::util::run_in_thread_with_globals<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}::{closure#0}::{closure#0}>
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
error: could not compile `kumo-spf` (lib)

Full log: https://paste.rs/HCkYZ

[gavinleroy]

Thank you for tracking that down!

I believe this is a problem with how Argus invokes some rustc APIs, I'll need to investigate further

[djc]

It's weird because it seems very intermittent, happens seemingly randomly while switching tabs to another file. (I do have autosaving enabled so could maybe be triggered by a change? But I don't think I was making a change at the time.)