'rustc' panicked at 'forcing query with already existing `DepNode`

[timbru]

Hi,

We run cargo clippy --all --all-features -- -D warnings using Github actions for our project and it started failing with a compiler panic. I have the same issues if I run this on my Mac mini M1. If I just run cargo clippy --all --all-features it works, and I get no warnings.

This seems to have been triggered by this commit:
NLnetLabs/rpki-rs@67c6b99

Output of the error from my machine:

thread 'rustc' panicked at 'forcing query with already existing `DepNode`
- query-key: ParamEnvAnd { param_env: ParamEnv { caller_bounds: [Binder(TraitPredicate(<R as std::io::BufRead>, polarity:Positive), []), Binder(TraitPredicate(<R as std::io::Read>, polarity:Positive), []), Binder(TraitPredicate(<R as std::marker::Sized>, polarity:Positive), [])], reveal: UserFacing }, value: Const { ty: xml::decode::Name, val: Value(ByRef { alloc: Allocation { bytes: [0, 0, 0, 0, 0, 0, 0, 0, 49, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [(Size { raw: 0 }, alloc194), (Size { raw: 16 }, alloc153)] }), init_mask: InitMask { blocks: [4294967295], len: Size { raw: 32 } }, align: Align { pow2: 3 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) } }
- dep-node: destructure_const(dbbd680d64dbbc1d-1e554034797ecc7c)', /rustc/db9d1b20bba1968c1ec1fc49616d4742c1725b4b/compiler/rustc_query_system/src/dep_graph/graph.rs:236:9
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-clippy/issues/new

note: Clippy version: clippy 0.1.58 (db9d1b20 2022-01-20)

query stack during panic:
#0 [destructure_const] destructure constant
#1 [check_match] match-checking `remote::publication::<impl at src/remote/publication.rs:552:1: 717:2>::decode::{closure#0}`
end of query stack
error: could not compile `rpki`

[timbru]

Update:

It also happened during a verbose build: cargo build --all-features --verbose.

I managed to work around the issue in this commit:
NLnetLabs/rpki-rs@021bbb3

It is somehow related to a match that I am doing using const values, when I changed this match here to use a const &[u8] instead of our own type things worked again:
https://github.com/NLnetLabs/rpki-rs/blob/021bbb3cb9db07332d7438883f30238f39ea37b6/src/remote/publication.rs#L607

Somehow it was still okay with other such occurrences.

In any case.. I have refactored my code and this is not in my way anymore. Leaving this here as it seems to point to some issue.

[giraffate]

Thanks for the report!

It's a duplicate of rust-lang/rust#89690, so I'm closing this.

[deepu105]

Seeing this again when running clippy in Rust 1.73, don't have it in 1.72

rust-lang/rust#83085 (comment)