Panic during 'hir_expand'

[xldenis]

When trying to view RA diagnostics I found this message instead:

rust-analyzer: [ERROR hir_expand] Failed mapping up more for 20..27
rust-analyzer: thread '<unnamed>' panicked at 'internal error: entered unreachable code: pattern has unexpected type: pat: Pat { ty: FnDefId(44)<[?0 := {error}]>, kind: Variant { substs: [?0 := {error}], enum_variant: EnumVariantId { parent: EnumId(21), local_id: Idx::<EnumVariantData>(1) }, subpatterns: [] } }, ty: FnDefId(44)<[?0 := {error}]>', crates/hir_ty/src/diagnostics/match_check/deconstruct_pat.rs:947:25
rust-analyzer: stack backtrace:
rust-analyzer:    0: rust_begin_unwind
rust-analyzer:              at /rustc/f1edd0429582dd29cccacaf50fd134b05593bd9c/library/std/src/panicking.rs:517:5
rust-analyzer:    1: core::panicking::panic_fmt
rust-analyzer:              at /rustc/f1edd0429582dd29cccacaf50fd134b05593bd9c/library/core/src/panicking.rs:100:14
rust-analyzer:    2: hir_ty::diagnostics::match_check::deconstruct_pat::DeconstructedPat::from_pat
rust-analyzer:    3: hir_ty::diagnostics::expr::BodyValidationDiagnostic::collect
rust-analyzer:    4: hir::DefWithBody::diagnostics
rust-analyzer:    5: hir::ModuleDef::diagnostics
rust-analyzer:    6: hir::Module::diagnostics
rust-analyzer:    7: ide_diagnostics::diagnostics
rust-analyzer:    8: std::panicking::try
rust-analyzer:    9: ide::Analysis::diagnostics
rust-analyzer:   10: rust_analyzer::handlers::publish_diagnostics
rust-analyzer:   11: core::ops::function::impls::<impl core::ops::function::FnMut<A> for &mut F>::call_mut
rust-analyzer:   12: alloc::vec::source_iter_marker::<impl alloc::vec::spec_from_iter::SpecFromIter<T,I> for alloc::vec::Vec<T>>::from_iter
rust-analyzer:   13: <F as threadpool::FnBox>::call_box
rust-analyzer: note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
rust-analyzer: [ERROR hir_expand] Failed mapping up more for 20..27
rust-analyzer: Panic context:
rust-analyzer: >
rust-analyzer: version: c574cf351 2022-01-06 dev
rust-analyzer: request: textDocument/documentHighlight DocumentHighlightParams {
rust-analyzer:     text_document_position_params: TextDocumentPositionParams {
rust-analyzer:         text_document: TextDocumentIdentifier {
rust-analyzer:             uri: Url {
rust-analyzer:                 scheme: "file",
rust-analyzer:                 cannot_be_a_base: false,
rust-analyzer:                 username: "",
rust-analyzer:                 password: None,
rust-analyzer:                 host: None,
rust-analyzer:                 port: None,
rust-analyzer:                 path: "/Users/xavier/Code/creusot/creusot/tests/should_succeed/syntax/07_extern_spec.rs",
rust-analyzer:                 query: None,
rust-analyzer:                 fragment: None,
rust-analyzer:             },
rust-analyzer:         },
rust-analyzer:         position: Position {
rust-analyzer:             line: 13,
rust-analyzer:             character: 21,
rust-analyzer:         },
rust-analyzer:     },
rust-analyzer:     work_done_progress_params: WorkDoneProgressParams {
rust-analyzer:         work_done_token: None,
rust-analyzer:     },
rust-analyzer:     partial_result_params: PartialResultParams {
rust-analyzer:         partial_result_token: None,
rust-analyzer:     },
rust-analyzer: }
rust-analyzer: 
rust-analyzer: thread '<unnamed>' panicked at 'Bad offset: range 0..220 offset 221', /Users/xavier/.cargo/registry/src/gb.xjqchip.workers.dev-1ecc6299db9ec823/rowan-0.15.2/src/cursor.rs:751:9
rust-analyzer: stack backtrace:
rust-analyzer:    0: rust_begin_unwind
rust-analyzer:              at /rustc/f1edd0429582dd29cccacaf50fd134b05593bd9c/library/std/src/panicking.rs:517:5
rust-analyzer:    1: core::panicking::panic_fmt
rust-analyzer:              at /rustc/f1edd0429582dd29cccacaf50fd134b05593bd9c/library/core/src/panicking.rs:100:14
rust-analyzer:    2: rowan::cursor::SyntaxNode::token_at_offset
rust-analyzer:    3: ide::highlight_related::highlight_related
rust-analyzer:    4: std::panicking::try
rust-analyzer:    5: ide::Analysis::highlight_related
rust-analyzer:    6: rust_analyzer::handlers::handle_document_highlight
rust-analyzer:    7: std::panicking::try
rust-analyzer:    8: <F as threadpool::FnBox>::call_box
rust-analyzer: note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

I'm using rust-analyzer c574cf351 2022-01-06 dev, with rustc 1.60.0-nightly (ad46af247 2022-01-14) inside ST4.

In all fairness the project I'm working on is not the most typical Rust project, it's a rustc driver which also makes heavy use of proc macros.

[iDawer]

Do are both panics come when opening creusot/creusot/tests/should_succeed/syntax/07_extern_spec.rs file?

Regarding the first panic could you provide please an expansion of the extern_spec! macro call there? I'd like to look into generated match expressions.

[xldenis]

Yes of course, I should add this crash is not deterministic, ie: while getting the expanded form for you I didn't encounter the issue, however here is the expansion of that file:

#![feature(prelude_import)]
#![no_std]
#[prelude_import]
use ::std::prelude::rust_2015::*;
#[macro_use]
extern crate std;
extern crate creusot_contracts;
use creusot_contracts::*;

#[creusot::spec::requires =
  "extern_spec_b7977fad_f137_461f_bd4c_aaedc58f42a2_3dec2d31_da27_4359_a823_012d79f94ede"]
#[creusot::no_translate]
#[creusot::extern_spec]
fn extern_spec_b7977fad_f137_461f_bd4c_aaedc58f42a2<T>() -> Vec<T> {
    #[allow(unused_must_use)]
    let _ =
        #[creusot::no_translate] #[creusot::item =
                                   "extern_spec_b7977fad_f137_461f_bd4c_aaedc58f42a2_3dec2d31_da27_4359_a823_012d79f94ede"] #[creusot::decl::spec] ||
                                                                                                                                                       {
                                                                                                                                                           creusot_contracts::stubs::equal(true,
                                                                                                                                                                                           true)
                                                                                                                                                       };
    std::vec::Vec::new()
}

fn main() { let v: Vec<bool> = Vec::new(); }

Created using rustc --extern creusot_contracts=./target/debug/libcreusot_contracts.rlib -Ldependency=./target/debug/deps/ -Zunpretty=expanded creusot/tests/should_succeed/syntax/07_extern_spec.rs

[flodiebold]

@xldenis were you using a build of rust-analyzer with debug_assertions enabled? That error shouldn't be a panic in release builds 😕
Your expanded code doesn't contain any matches, so it's probably not the problematic code.

Actually, there are two seemingly unrelated panics here, the Bad offset: range 0..220 offset 221 and the pattern has unexpected type one.

[xldenis]

I installed from source using the steps in the readme, that is: cargo xtask install --server

[iDawer]

The first error comes from match check diagnostic on creusot/src/translation/function/statement.rs. It has been resolved in #11899.

@xldenis I see {error}'s in the log. I've got the same when "rust-analyzer.rustcSource": "discover", was not set. Is it set for you? Does rust-analyzer resolve rustc sources?

[xldenis]

Is it set for you?

Yes

Does rust-analyzer resolve rustc sources?

Yes quite well in fact :)

[Veykril]

Closing as there is not much to do here from our side