rust-lang / rust-lang/rust

[ICE]: found unstable fingerprints for trait_explicit_predicates_and_bounds

Open
#158,203 0 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

C-bug I-ICE needs-triage S-needs-repro T-compiler
Dominant language
Rust
Stars
119k
Forks
16.1k
PR metrics pending

Description

Code

Unfortunately the code cannot be provided.

Meta

rustc --version --verbose:

rustc 1.55.0 (c8dfcfe04 2021-09-06)
binary: rustc
commit-hash: c8dfcfe046a7680554bf4eb612bad840e7631c4b
commit-date: 2021-09-06
host: x86_64-unknown-linux-gnu
release: 1.55.0
LLVM version: 12.0.1
Error output
thread 'rustc' panicked at /rustc-dev/bc2112ed56c99fa649e09ab3ab286afab3d9059a/compiler/rustc_middle/src/verify_ich.rs:82:9:
Found unstable fingerprints for trait_explicit_predicates_and_bounds(my_crate[e7b1]::RoTable): GenericPredicates { parent: None, predicates: [(Binder { value: TraitPredicate(<Self as std::marker::MetaSized>, polarity:Positive), bound_vars: [] }, my-crate/src/lib.rs:157:1: 170:2 (#112)), (Binder { value: TraitPredicate(<K as std::marker::Sized>, polarity:Positive), bound_vars: [] }, my-crate/src/lib.rs:157:19: 157:20 (#113)), (Binder { value: TraitPredicate(<V as std::marker::Sized>, polarity:Positive), bound_vars: [] }, my-crate/src/lib.rs:157:22: 157:23 (#114)), (Binder { value: TraitPredicate(<K as ende::en::Encode>, polarity:Positive), bound_vars: [] }, my-crate/src/lib.rs:159:8: 159:18 (#0)), (Binder { value: TraitPredicate(<K as ende::de::Decode>, polarity:Positive), bound_vars: [] }, my-crate/src/lib.rs:159:21: 159:31 (#0)), (Binder { value: TraitPredicate(<V as ende::de::Decode>, polarity:Positive), bound_vars: [] }, my-crate/src/lib.rs:160:8: 160:18 (#0))] }
Backtrace 

stack backtrace:
   0:     0x7f6dcb1dcccb - <std[9155b05baf46f0b5]::backtrace::Backtrace>::create
   1:     0x7f6dcb1dcc15 - <std[9155b05baf46f0b5]::backtrace::Backtrace>::force_capture
   2:     0x7f6dca24a73d - std[9155b05baf46f0b5]::panicking::update_hook::<alloc[4a86d35f348a3b04]::boxed::Box<rustc_driver_impl[b791fc15675dcea2]::install_ice_hook::{closure#1}>>::{closure#0}
   3:     0x7f6dcb1f0852 - std[9155b05baf46f0b5]::panicking::panic_with_hook
   4:     0x7f6dcb1d2c42 - std[9155b05baf46f0b5]::panicking::panic_handler::{closure#0}
   5:     0x7f6dcb1c7169 - std[9155b05baf46f0b5]::sys::backtrace::__rust_end_short_backtrace::<std[9155b05baf46f0b5]::panicking::panic_handler::{closure#0}, !>
   6:     0x7f6dcb1d46ad - __rustc[b4c4dac14d05b73]::rust_begin_unwind
   7:     0x7f6dc810455c - core[b26e7c5dab710dcd]::panicking::panic_fmt
   8:     0x7f6dca7f0f46 - rustc_middle[cb7c4bb37f51aac1]::verify_ich::incremental_verify_ich_failed
   9:     0x7f6dccae5b55 - rustc_middle[cb7c4bb37f51aac1]::verify_ich::incremental_verify_ich::<rustc_middle[cb7c4bb37f51aac1]::query::erase::ErasedData<[u8; 24usize]>>
  10:     0x7f6dcc65ecd1 - rustc_query_impl[f814d044a8094e2a]::execution::try_execute_query::<rustc_data_structures[788feccef7b56953]::vec_cache::VecCache<rustc_span[4065efe3f3bc8177]::def_id::LocalDefId, rustc_middle[cb7c4bb37f51aac1]::query::erase::ErasedData<[u8; 24usize]>, rustc_middle[cb7c4bb37f51aac1]::dep_graph::graph::DepNodeIndex>, true>
  11:     0x7f6dcc65e409 - rustc_query_impl[f814d044a8094e2a]::query_impl::trait_explicit_predicates_and_bounds::execute_query_incr::__rust_end_short_backtrace
  12:     0x7f6dcc917baf - rustc_hir_analysis[f8649c0bc5b32aaa]::collect::item_bounds::associated_type_bounds
  13:     0x7f6dcc916948 - rustc_hir_analysis[f8649c0bc5b32aaa]::collect::item_bounds::explicit_item_bounds_with_filter
  14:     0x7f6dcc916814 - rustc_hir_analysis[f8649c0bc5b32aaa]::collect::item_bounds::explicit_item_bounds
  15:     0x7f6dcc9167f2 - rustc_query_impl[f814d044a8094e2a]::query_impl::explicit_item_bounds::invoke_provider_fn::__rust_begin_short_backtrace
  16:     0x7f6dcbe4c939 - rustc_query_impl[f814d044a8094e2a]::execution::try_execute_query::<rustc_middle[cb7c4bb37f51aac1]::query::caches::DefIdCache<rustc_middle[cb7c4bb37f51aac1]::query::erase::ErasedData<[u8; 16usize]>>, true>
  17:     0x7f6dcbe4a161 - rustc_query_impl[f814d044a8094e2a]::execution::force_query_dep_node::<rustc_middle[cb7c4bb37f51aac1]::query::caches::DefIdCache<rustc_middle[cb7c4bb37f51aac1]::query::erase::ErasedData<[u8; 16usize]>>>
  18:     0x7f6dcacfcbad - <rustc_query_impl[f814d044a8094e2a]::dep_kind_vtables::make_dep_kind_vtable_for_query<rustc_query_impl[f814d044a8094e2a]::query_impl::explicit_item_bounds::VTableGetter>::{closure#0} as core[b26e7c5dab710dcd]::ops::function::FnOnce<(rustc_middle[cb7c4bb37f51aac1]::ty::context::TyCtxt, rustc_middle[cb7c4bb37f51aac1]::dep_graph::dep_node::DepNode, rustc_middle[cb7c4bb37f51aac1]::dep_graph::serialized::SerializedDepNodeIndex)>>::call_once
  19:     0x7f6dcb823e63 - <rustc_middle[cb7c4bb37f51aac1]::dep_graph::graph::DepGraphData>::try_mark_previous_green
  20:     0x7f6dcb823a94 - <rustc_middle[cb7c4bb37f51aac1]::dep_graph::graph::DepGraphData>::try_mark_previous_green
  21:     0x7f6dcb823a94 - <rustc_middle[cb7c4bb37f51aac1]::dep_graph::graph::DepGraphData>::try_mark_previous_green
  22:     0x7f6dcb823a94 - <rustc_middle[cb7c4bb37f51aac1]::dep_graph::graph::DepGraphData>::try_mark_previous_green
  23:     0x7f6dcb823a94 - <rustc_middle[cb7c4bb37f51aac1]::dep_graph::graph::DepGraphData>::try_mark_previous_green
  24:     0x7f6dcbba6923 - <rustc_middle[cb7c4bb37f51aac1]::dep_graph::graph::DepGraph>::try_mark_green
  25:     0x7f6dcbba66e5 - rustc_query_impl[f814d044a8094e2a]::execution::ensure_can_skip_execution::<rustc_data_structures[788feccef7b56953]::vec_cache::VecCache<rustc_span[4065efe3f3bc8177]::def_id::CrateNum, rustc_middle[cb7c4bb37f51aac1]::query::erase::ErasedData<[u8; 16usize]>, rustc_middle[cb7c4bb37f51aac1]::dep_graph::graph::DepNodeIndex>>
  26:     0x7f6dccb25b46 - rustc_query_impl[f814d044a8094e2a]::query_impl::check_type_wf::execute_query_incr::__rust_end_short_backtrace
  27:     0x7f6dcbca781e - rustc_hir_analysis[f8649c0bc5b32aaa]::check_crate
  28:     0x7f6dcbca9d0c - rustc_interface[84e7048b04034882]::passes::analysis
  29:     0x7f6dcca607c2 - rustc_query_impl[f814d044a8094e2a]::execution::try_execute_query::<rustc_middle[cb7c4bb37f51aac1]::query::caches::SingleCache<rustc_middle[cb7c4bb37f51aac1]::query::erase::ErasedData<[u8; 0usize]>>, true>
  30:     0x7f6dcca600f7 - rustc_query_impl[f814d044a8094e2a]::query_impl::analysis::execute_query_incr::__rust_end_short_backtrace
  31:     0x7f6dcc999c52 - rustc_interface[84e7048b04034882]::interface::run_compiler::<(), rustc_driver_impl[b791fc15675dcea2]::run_compiler::{closure#0}>::{closure#1}
  32:     0x7f6dcc9ceffa - std[9155b05baf46f0b5]::sys::backtrace::__rust_begin_short_backtrace::<rustc_interface[84e7048b04034882]::util::run_in_thread_with_globals<rustc_interface[84e7048b04034882]::util::run_in_thread_pool_with_globals<rustc_interface[84e7048b04034882]::interface::run_compiler<(), rustc_driver_impl[b791fc15675dcea2]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>
  33:     0x7f6dcc9cedad - <std[9155b05baf46f0b5]::thread::lifecycle::spawn_unchecked<rustc_interface[84e7048b04034882]::util::run_in_thread_with_globals<rustc_interface[84e7048b04034882]::util::run_in_thread_pool_with_globals<rustc_interface[84e7048b04034882]::interface::run_compiler<(), rustc_driver_impl[b791fc15675dcea2]::run_compiler::{closure#0}>::{closure#1}, ()>::{closure#0}, ()>::{closure#0}::{closure#0}, ()>::{closure#1} as core[b26e7c5dab710dcd]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  34:     0x7f6dcc9c5290 - <std[9155b05baf46f0b5]::sys::thread::unix::Thread>::new::thread_start
  35:     0x7f6dc66a755f - <unknown>
  36:     0x7f6dc67265ac - <unknown>
  37:                0x0 - <unknown>


rustc version: 1.98.0-nightly (bc2112ed5 2026-06-18)
platform: x86_64-unknown-linux-gnu

query stack during panic:
#0 [trait_explicit_predicates_and_bounds] computing explicit predicates of trait `RoTable`
#1 [explicit_item_bounds] finding item bounds for `RoTable::prefix::{anon_assoc#0}`
#2 [analysis] running analysis passes on crate `my_crate`
end of query stack

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with compiler/rustc_middle/src/verify_ich.rs at the reported panic and trace the trait_explicit_predicates_and_bounds query through explicit_item_bounds and analysis. The report provides no reproducible code, so first determine whether the unstable fingerprint can be reproduced; done means the compiler no longer panics for a reproducer and the behavior is covered by an appropriate regression test.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
compilers
Issue type
Bug
Difficulty
5/5
Estimated time
Over a week
Activity status
Quiet
Clarity
Needs clarification
Newbie friendliness
20/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.