incremental ICE: fingerprints for evaluate_obligation compiling chalk

[matthiaskrgr]

Code

This happens with the chalk crate

git clone https://github.com/rust-lang/chalk
cd chalk
git checkout f7c7856edee8f80636f5a9ef6edc8a1fd42ed940
cargo build
find . | grep \.rs$ | xargs touch   
cargo build # => boom

Meta

rustc --version --verbose:

rustc 1.52.0-nightly (acca81892 2021-03-13)
binary: rustc
commit-hash: acca818928654807ed3bc1ce0e97df118f8716c8
commit-date: 2021-03-13
host: x86_64-unknown-linux-gnu
release: 1.52.0-nightly
LLVM version: 12.0.0

Error output

   Compiling lalrpop v0.19.0
   Compiling chalk-solve v0.62.0-dev.0 (/tmp/chalk/chalk-solve)
   Compiling chalk-parse v0.62.0-dev.0 (/tmp/chalk/chalk-parse)
   Compiling chalk-engine v0.62.0-dev.0 (/tmp/chalk/chalk-engine)
   Compiling chalk-recursive v0.62.0-dev.0 (/tmp/chalk/chalk-recursive)
   Compiling chalk-integration v0.62.0-dev.0 (/tmp/chalk/chalk-integration)
thread 'rustc' panicked at 'found unstable fingerprints for evaluate_obligation(e3239918b04f5ea6-d9d33836ead20deb)', /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/compiler/rustc_query_system/src/query/plumbing.rs:593:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

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 1.52.0-nightly (acca81892 2021-03-13) running on x86_64-unknown-linux-gnu

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

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

query stack during panic:
#0 [evaluate_obligation] evaluating trait selection obligation `chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>: std::marker::Sized`
#1 [normalize_projection_ty] normalizing `Canonical { max_universe: U0, variables: [], value: ParamEnvAnd { param_env: ParamEnv { caller_bounds: [], reveal: All }, value: ProjectionTy { substs: [std::iter::Map<chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>, [closure@<chalk_solve::rust_ir::AssociatedTyValue<interner::ChalkIr> as chalk_solve::clauses::program_clauses::ToProgramClauses<interner::ChalkIr>>::to_program_clauses::{closure#0}::{closure#3}]>], item_def_id: DefId(2:6999 ~ core[3998]::iter::traits::collect::IntoIterator::IntoIter) } } }`
end of query stack
error: could not compile `chalk-integration`

Backtrace

thread 'rustc' panicked at 'found unstable fingerprints for evaluate_obligation(e3239918b04f5ea6-d9d33836ead20deb)', /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/compiler/rustc_query_system/src/query/plumbing.rs:593:5
stack backtrace:
   0:     0x7f1905b59930 - std::backtrace_rs::backtrace::libunwind::trace::hfe3b1cace85e87d8
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/../../backtrace/src/backtrace/libunwind.rs:90:5
   1:     0x7f1905b59930 - std::backtrace_rs::backtrace::trace_unsynchronized::h542330af06479043
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f1905b59930 - std::sys_common::backtrace::_print_fmt::h6b88726367858985
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/sys_common/backtrace.rs:67:5
   3:     0x7f1905b59930 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hcd76ce6b485adbea
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/sys_common/backtrace.rs:46:22
   4:     0x7f1905bc7abf - core::fmt::write::h127419eb46f2ecc9
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/core/src/fmt/mod.rs:1092:17
   5:     0x7f1905b4da42 - std::io::Write::write_fmt::h0facb64ef2e7f5d8
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/io/mod.rs:1567:15
   6:     0x7f1905b5d675 - std::sys_common::backtrace::_print::h7bf1633ea5421f7b
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/sys_common/backtrace.rs:49:5
   7:     0x7f1905b5d675 - std::sys_common::backtrace::print::h5cc4d09049928ba5
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/sys_common/backtrace.rs:36:9
   8:     0x7f1905b5d675 - std::panicking::default_hook::{{closure}}::h9e84dc005bfc9fc7
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/panicking.rs:208:50
   9:     0x7f1905b5d1d3 - std::panicking::default_hook::h123278a03b1f796b
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/panicking.rs:225:9
  10:     0x7f190632f3fb - rustc_driver::report_ice::h036d06dbb7c2c24c
  11:     0x7f18ed8764f3 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h09b6f9ae26022dbe
                               at /home/matthias/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/boxed.rs:1560:9
  12:     0x7f18ed884836 - proc_macro::bridge::client::<impl proc_macro::bridge::Bridge>::enter::{{closure}}::{{closure}}::hefb8f10999b1a6c9
                               at /home/matthias/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/proc_macro/src/bridge/client.rs:320:21
  13:     0x7f1905b5dde0 - std::panicking::rust_panic_with_hook::h4040631aa6c7bc27
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/panicking.rs:595:17
  14:     0x7f1905b5d957 - std::panicking::begin_panic_handler::{{closure}}::h02a17b22ac092d08
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/panicking.rs:497:13
  15:     0x7f1905b59dec - std::sys_common::backtrace::__rust_end_short_backtrace::h6063b024443b5852
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/sys_common/backtrace.rs:141:18
  16:     0x7f1905b5d8b9 - rust_begin_unwind
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/panicking.rs:493:5
  17:     0x7f1905b2203b - std::panicking::begin_panic_fmt::h10b51f96d6207ff1
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/panicking.rs:435:5
  18:     0x7f19084a4809 - rustc_query_system::query::plumbing::incremental_verify_ich::h05b884ecbbf51fd4
  19:     0x7f19084aca01 - rustc_query_system::query::plumbing::load_from_disk_and_cache_in_memory::h867c5b7e6e93eed6
  20:     0x7f19084c0c28 - rustc_data_structures::stack::ensure_sufficient_stack::h69fbfd9dd474f86f
  21:     0x7f190799fd06 - rustc_query_system::query::plumbing::get_query_impl::ha8a27c9cad3ab0ff
  22:     0x7f19079f5833 - <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::evaluate_obligation::h6779a474fcff6b3d
  23:     0x7f1907e97fa1 - <rustc_infer::infer::InferCtxt as rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt>::evaluate_obligation::hf892191b66f145b6
  24:     0x7f1907e981a0 - <rustc_infer::infer::InferCtxt as rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt>::evaluate_obligation_no_overflow::hf88d6e76ac547df5
  25:     0x7f1907ea0914 - rustc_trait_selection::traits::fulfill::FulfillProcessor::process_trait_obligation::h22b93a7d22097138
  26:     0x7f1907e9f091 - rustc_trait_selection::traits::fulfill::FulfillProcessor::progress_changed_obligations::ha00d22645f34c749
  27:     0x7f1907eb4994 - rustc_data_structures::obligation_forest::ObligationForest<O>::process_obligations::hcb7d4f2d75404ae5
  28:     0x7f1907e9ebb6 - <rustc_trait_selection::traits::fulfill::FulfillmentContext as rustc_infer::traits::engine::TraitEngine>::select_where_possible::hb21f38706f3ef1ce
  29:     0x7f1908237b21 - <rustc_infer::infer::InferCtxtBuilder as rustc_trait_selection::infer::InferCtxtBuilderExt>::enter_canonical_trait_query::h9e8771b7b83dd016
  30:     0x7f190823ade7 - rustc_traits::normalize_projection_ty::normalize_projection_ty::h9df43f7fb0706b28
  31:     0x7f19084baab6 - rustc_query_impl::<impl rustc_query_system::query::config::QueryAccessors<rustc_query_impl::plumbing::QueryCtxt> for rustc_query_impl::queries::normalize_projection_ty>::compute::h9da8acf630b1a05d
  32:     0x7f19069c563c - rustc_query_system::query::config::QueryVtable<CTX,K,V>::compute::hd06f761d3342c820
  33:     0x7f1906b63b19 - rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps::h87c0eea4975040f5
  34:     0x7f1906aaab9f - rustc_query_system::dep_graph::graph::DepGraph<K>::with_ignore::ha306d91155a0d536
  35:     0x7f19069742cb - rustc_query_system::query::plumbing::load_from_disk_and_cache_in_memory::h38741992d06ef360
  36:     0x7f19084c260b - rustc_data_structures::stack::ensure_sufficient_stack::ha17f9b92d16e2497
  37:     0x7f190844af70 - rustc_query_system::query::plumbing::get_query_impl::h980fc17272b2bac8
  38:     0x7f190852b427 - <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::normalize_projection_ty::h3e9345a583e17be8
  39:     0x7f1907ea11aa - <rustc_trait_selection::traits::query::normalize::QueryNormalizer as rustc_middle::ty::fold::TypeFolder>::fold_ty::hc869c3da976a3493
  40:     0x7f1907e9c5a5 - rustc_middle::ty::fold::TypeFoldable::fold_with::hcbc0e67575b7c505
  41:     0x7f1907ee702f - rustc_middle::ty::structural_impls::<impl rustc_middle::ty::fold::TypeFoldable for &rustc_middle::ty::TyS>::super_fold_with::h3aa49e1bbcb3a364
  42:     0x7f1907ea0c5f - <rustc_trait_selection::traits::query::normalize::QueryNormalizer as rustc_middle::ty::fold::TypeFolder>::fold_ty::hc869c3da976a3493
  43:     0x7f1907716128 - <rustc_infer::infer::at::At as rustc_trait_selection::traits::query::normalize::AtExt>::normalize::hf222a0482fb341e2
  44:     0x7f1907714256 - rustc_infer::infer::InferCtxtBuilder::enter::h3a3eb22ae58e478f
  45:     0x7f1907716c7a - rustc_traits::normalize_erasing_regions::normalize_generic_arg_after_erasing_regions::h005ef1d2d20883c8
  46:     0x7f1906b59914 - rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps::h2db1958328ab07c7
  47:     0x7f1906aab1cc - rustc_query_system::dep_graph::graph::DepGraph<K>::with_ignore::he3f25a72f93d852b
  48:     0x7f1906978075 - rustc_query_system::query::plumbing::load_from_disk_and_cache_in_memory::h6f10869d8f3d56ab
  49:     0x7f19084c66b0 - rustc_data_structures::stack::ensure_sufficient_stack::hfdb747dde41ae689
  50:     0x7f19079a4113 - rustc_query_system::query::plumbing::get_query_impl::hb2c100313112ca48
  51:     0x7f19079f5699 - <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::normalize_generic_arg_after_erasing_regions::h84b86402eb1ff5de
  52:     0x7f1907fd7e98 - <rustc_middle::ty::normalize_erasing_regions::NormalizeAfterErasingRegionsFolder as rustc_middle::ty::fold::TypeFolder>::fold_ty::h237c91612a2a365e
  53:     0x7f1907b6b21e - <rustc_mir::monomorphize::collector::MirNeighborCollector as rustc_middle::mir::visit::Visitor>::visit_terminator::h0bf2654c31e0daee
  54:     0x7f1907b6daf7 - rustc_mir::monomorphize::collector::collect_neighbours::hdb969d412161bcd5
  55:     0x7f1907b677ce - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  56:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  57:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  58:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  59:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  60:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  61:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  62:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  63:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  64:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  65:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  66:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  67:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  68:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  69:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  70:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  71:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  72:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  73:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  74:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  75:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  76:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  77:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  78:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  79:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  80:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  81:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  82:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  83:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  84:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  85:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  86:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  87:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  88:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  89:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  90:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  91:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  92:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  93:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  94:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  95:     0x7f1907b678c2 - rustc_mir::monomorphize::collector::collect_items_rec::h3721b047c4f9883e
  96:     0x7f190867c4f3 - rustc_session::utils::<impl rustc_session::session::Session>::time::h0440f4f414c9ef02
  97:     0x7f190865968f - rustc_mir::monomorphize::collector::collect_crate_mono_items::h7b2de256f929a618
  98:     0x7f19086830d1 - rustc_mir::monomorphize::partitioning::collect_and_partition_mono_items::h63793682e86156a6
  99:     0x7f19084ba816 - rustc_query_impl::<impl rustc_query_system::query::config::QueryAccessors<rustc_query_impl::plumbing::QueryCtxt> for rustc_query_impl::queries::collect_and_partition_mono_items>::compute::h78d360549ea1445a
 100:     0x7f1906b630d2 - rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps::h84096843adea5251
 101:     0x7f1908551029 - rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl::hc9d4ad7fd89c2c9c
 102:     0x7f19084bda49 - rustc_data_structures::stack::ensure_sufficient_stack::h2203d7d1590a246c
 103:     0x7f1908485e06 - rustc_query_system::query::plumbing::force_query_with_job::h845e082b4c1c35bd
 104:     0x7f1906929e3d - rustc_query_system::query::plumbing::force_query_impl::h78d71823a415af29
 105:     0x7f19068f992b - rustc_query_system::query::plumbing::force_query::heb2cf16257c27c3b
 106:     0x7f19069cd1aa - rustc_query_impl::query_callbacks::collect_and_partition_mono_items::force_from_dep_node::h3d94b3d33ba0799a
 107:     0x7f1907a0eb58 - rustc_query_system::dep_graph::graph::DepGraph<K>::try_mark_previous_green::h9257a9babe92c54c
 108:     0x7f1907a0e975 - rustc_query_system::dep_graph::graph::DepGraph<K>::try_mark_green_and_read::hbf9b915c03770b75
 109:     0x7f19084c13bb - rustc_data_structures::stack::ensure_sufficient_stack::h7fa65d951e50b4fd
 110:     0x7f19084411c5 - rustc_query_system::query::plumbing::get_query_impl::h7ba870440529c740
 111:     0x7f190852af9f - <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::exported_symbols::h995c15aeed103867
 112:     0x7f1907cff311 - rustc_metadata::rmeta::encoder::EncodeContext::encode_crate_root::hcb36823456f51dd6
 113:     0x7f1908752e46 - rustc_metadata::rmeta::encoder::encode_metadata_impl::h0790ae1c4e3ddfae
 114:     0x7f190876cef1 - rustc_data_structures::sync::join::h9d9a97d6c927a0d2
 115:     0x7f190875ab5e - rustc_metadata::rmeta::decoder::cstore_impl::<impl rustc_middle::middle::cstore::CrateStore for rustc_metadata::creader::CStore>::encode_metadata::h33472d8fd43fc7ed
 116:     0x7f190897d465 - rustc_middle::ty::context::TyCtxt::encode_metadata::h12bbfca9093c4007
 117:     0x7f19080aa19e - rustc_interface::passes::QueryContext::enter::h7ccf5bf25c21ab1e
 118:     0x7f19080b1c46 - rustc_interface::queries::Queries::ongoing_codegen::h8d1f35e791cf687b
 119:     0x7f190806c606 - rustc_interface::queries::<impl rustc_interface::interface::Compiler>::enter::h8ab0a704bae2634f
 120:     0x7f1908066bf1 - rustc_span::with_source_map::h512fd197bcd2b7c3
 121:     0x7f190806bee3 - scoped_tls::ScopedKey<T>::set::hd407f010a973eb63
 122:     0x7f190806d3a4 - std::sys_common::backtrace::__rust_begin_short_backtrace::h3c42279179caa5db
 123:     0x7f1908088765 - core::ops::function::FnOnce::call_once{{vtable.shim}}::hd56f564efc764ea1
 124:     0x7f1905b6d258 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hd8ea7ada17dfa868
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/alloc/src/boxed.rs:1546:9
 125:     0x7f1905b6d258 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h91ce3a636c58b978
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/alloc/src/boxed.rs:1546:9
 126:     0x7f1905b6d258 - std::sys::unix::thread::Thread::new::thread_start::h2e193c2e23720fdf
                               at /rustc/acca818928654807ed3bc1ce0e97df118f8716c8/library/std/src/sys/unix/thread.rs:71:17
 127:     0x7f1905a76299 - start_thread
 128:     0x7f190598b053 - clone
 129:                0x0 - <unknown>

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 1.52.0-nightly (acca81892 2021-03-13) running on x86_64-unknown-linux-gnu

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

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

query stack during panic:
#0 [evaluate_obligation] evaluating trait selection obligation `chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>: std::marker::Sized`
#1 [normalize_projection_ty] normalizing `Canonical { max_universe: U0, variables: [], value: ParamEnvAnd { param_env: ParamEnv { caller_bounds: [], reveal: All }, value: ProjectionTy { substs: [std::iter::Map<chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>, [closure@<chalk_solve::rust_ir::AssociatedTyValue<interner::ChalkIr> as chalk_solve::clauses::program_clauses::ToProgramClauses<interner::ChalkIr>>::to_program_clauses::{closure#0}::{closure#3}]>], item_def_id: DefId(2:6999 ~ core[3998]::iter::traits::collect::IntoIterator::IntoIter) } } }`
#2 [normalize_generic_arg_after_erasing_regions] normalizing `fn(std::iter::Map<chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>, [closure@<chalk_solve::rust_ir::AssociatedTyValue<interner::ChalkIr> as chalk_solve::clauses::program_clauses::ToProgramClauses<interner::ChalkIr>>::to_program_clauses::{closure#0}::{closure#1}]>, <std::iter::Map<chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>, [closure@<chalk_solve::rust_ir::AssociatedTyValue<interner::ChalkIr> as chalk_solve::clauses::program_clauses::ToProgramClauses<interner::ChalkIr>>::to_program_clauses::{closure#0}::{closure#3}]> as std::iter::IntoIterator>::IntoIter) -> std::iter::Chain<std::iter::Map<chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>, [closure@<chalk_solve::rust_ir::AssociatedTyValue<interner::ChalkIr> as chalk_solve::clauses::program_clauses::ToProgramClauses<interner::ChalkIr>>::to_program_clauses::{closure#0}::{closure#1}]>, <std::iter::Map<chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>, [closure@<chalk_solve::rust_ir::AssociatedTyValue<interner::ChalkIr> as chalk_solve::clauses::program_clauses::ToProgramClauses<interner::ChalkIr>>::to_program_clauses::{closure#0}::{closure#3}]> as std::iter::IntoIterator>::IntoIter> {std::iter::Chain::<std::iter::Map<chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>, [closure@<chalk_solve::rust_ir::AssociatedTyValue<interner::ChalkIr> as chalk_solve::clauses::program_clauses::ToProgramClauses<interner::ChalkIr>>::to_program_clauses::{closure#0}::{closure#1}]>, <std::iter::Map<chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>, [closure@<chalk_solve::rust_ir::AssociatedTyValue<interner::ChalkIr> as chalk_solve::clauses::program_clauses::ToProgramClauses<interner::ChalkIr>>::to_program_clauses::{closure#0}::{closure#3}]> as std::iter::IntoIterator>::IntoIter>::new}`
#3 [collect_and_partition_mono_items] collect_and_partition_mono_items
#4 [exported_symbols] exported_symbols
end of query stack
error: could not compile `chalk-integration`

To learn more, run the command again with --verbose.

[Aaron1011]

This is issue #80691 - it is now exposed due to #83007

[matthiaskrgr]

updated error msg with #83314 :

   Compiling chalk-integration v0.62.0-dev.0 (/home/matthias/vcs/github/chalk/chalk-integration)
thread 'rustc' panicked at 'found unstable fingerprints for evaluate_obligation(e3239918b04f5ea6-d9d33836ead20deb): Ok(EvaluatedToOk)', /rustc/61edfd591cedff66fca639c02f66984f6271e5a6/compiler/rustc_query_system/src/query/plumbing.rs:593:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

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 1.52.0-nightly (61edfd591 2021-03-20) running on x86_64-unknown-linux-gnu

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

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

query stack during panic:
#0 [evaluate_obligation] evaluating trait selection obligation `chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>: std::marker::Sized`
#1 [normalize_projection_ty] normalizing `Canonical { max_universe: U0, variables: [], value: ParamEnvAnd { param_env: ParamEnv { caller_bounds: [], reveal: All }, value: ProjectionTy { substs: [std::iter::Map<chalk_ir::BindersIntoIterator<&std::vec::Vec<chalk_ir::Binders<chalk_ir::WhereClause<interner::ChalkIr>>>>, [closure@<chalk_solve::rust_ir::AssociatedTyValue<interner::ChalkIr> as chalk_solve::clauses::program_clauses::ToProgramClauses<interner::ChalkIr>>::to_program_clauses::{closure#0}::{closure#3}]>], item_def_id: DefId(2:6993 ~ core[3998]::iter::traits::collect::IntoIterator::IntoIter) } } }`
end of query stack
error: could not compile `chalk-integration`

To learn more, run the command again with --verbose.

[lqd]

I've spent too much time on this 😅

Here's chalk reduced to 200 lines, triggering the incremental bug #80691. As always: cargo build && touch src/main.rs && cargo build to trigger the ICE.

It's small but not minimal per se: the Fold, Interner, and Binders abstractions could still be removed I presume. Still, it's pretty small compared to the full chalk + its dependencies, and should be a good starting point if someone wants to take it further down to a unit test.

EDIT: slightly further reduced, at 180 lines

[matthiaskrgr]

@Aaron1011 I can no longer reproduce the ICE with rustc 1.53.0-nightly (07e0e2ec2 2021-03-24).
Can this be closed?

[jyn514]

This was likely #83538, closing since it's fixed on nightly.