RLS crashes on clippyusing rustc 1.39.0-nightly (eb48d6bde 2019-09-12)

[arturoc]

thread 'rustc' panicked at 'index out of bounds: the len is 1 but the index is 18446744073709551613', src/tools/clippy/clippy_lints/src/misc_early.rs:511:16
stack backtrace:
   0: backtrace::backtrace::libunwind::trace
             at /cargo/registry/src/github.202132.xyz-1ecc6299db9ec823/backtrace-0.3.37/src/backtrace/libunwind.rs:88
   1: backtrace::backtrace::trace_unsynchronized
             at /cargo/registry/src/github.202132.xyz-1ecc6299db9ec823/backtrace-0.3.37/src/backtrace/mod.rs:66
   2: std::sys_common::backtrace::_print_fmt
             at src/libstd/sys_common/backtrace.rs:77
   3: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
             at src/libstd/sys_common/backtrace.rs:61
   4: core::fmt::write
             at src/libcore/fmt/mod.rs:1030
   5: std::io::Write::write_fmt
             at src/libstd/io/mod.rs:1412
   6: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:65
   7: std::sys_common::backtrace::print
             at src/libstd/sys_common/backtrace.rs:50
   8: std::panicking::default_hook::{{closure}}
             at src/libstd/panicking.rs:200
   9: std::panicking::default_hook
             at src/libstd/panicking.rs:214
  10: rustc::util::common::panic_hook
  11: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:481
  12: std::panicking::continue_panic_fmt
             at src/libstd/panicking.rs:384
  13: rust_begin_unwind
             at src/libstd/panicking.rs:311
  14: core::panicking::panic_fmt
             at src/libcore/panicking.rs:85
  15: core::panicking::panic_bounds_check
             at src/libcore/panicking.rs:61
  16: <clippy_lints::misc_early::MiscEarlyLints as rustc::lint::EarlyLintPass>::check_expr
  17: <rustc::lint::context::EarlyLintPassObjects as rustc::lint::EarlyLintPass>::check_expr
  18: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_expr
  19: syntax::visit::walk_expr
  20: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_expr
  21: syntax::visit::walk_expr
  22: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_expr
  23: syntax::visit::walk_fn
  24: syntax::visit::walk_impl_item
  25: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_impl_item
  26: syntax::visit::walk_item
  27: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_item
  28: syntax::visit::walk_item
  29: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_item
  30: syntax::visit::walk_item
  31: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_item
  32: syntax::visit::walk_crate
  33: rustc::lint::context::early_lint_crate
  34: rustc::lint::context::check_ast_crate
  35: rustc::util::common::time
  36: rustc_interface::passes::BoxedResolver::access::{{closure}}
  37: rustc_interface::passes::configure_and_expand::{{closure}}
  38: rustc_data_structures::box_region::PinnedGenerator<I,A,R>::access
  39: rustc_interface::queries::Query<T>::compute
  40: rustc_interface::queries::Query<T>::compute
  41: rustc_interface::queries::<impl rustc_interface::interface::Compiler>::prepare_outputs
  42: rustc_interface::interface::run_compiler_in_existing_thread_pool
  43: std::thread::local::LocalKey<T>::with
  44: scoped_tls::ScopedKey<T>::set
  45: syntax::with_globals
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
query stack during panic:
end of query stack

error: internal compiler error: unexpected panic

note: the compiler unexpectedly panicked. this is a bug.

[flip1995]

Can you share code on which this panic occurs?

[flip1995]

It may have something to do with this index:

rust-clippy/clippy_lints/src/misc_early.rs

Line 490 in 07c0673

let maybe_last_sep_idx = lit_snip.len() - suffix.len() - 1;

[arturoc]

This is happening while compiling a project with 300+ dependencies most of which are not public so it's hard to share. Not even sure which of the crates it's crashing but happy to do more tests if you give me any guidelines on how

[mati865]

Crash message should contain crate name at the bottom, if it's public crate knowing it's name could help.

[arturoc]

this is all i get in the output from RLS:

thread 'rustc' panicked at 'index out of bounds: the len is 1 but the index is 18446744073709551613', src/tools/clippy/clippy_lints/src/misc_early.rs:511:16
stack backtrace:
   0: backtrace::backtrace::libunwind::trace
             at /cargo/registry/src/github.202132.xyz-1ecc6299db9ec823/backtrace-0.3.37/src/backtrace/libunwind.rs:88
   1: backtrace::backtrace::trace_unsynchronized
             at /cargo/registry/src/github.202132.xyz-1ecc6299db9ec823/backtrace-0.3.37/src/backtrace/mod.rs:66
   2: std::sys_common::backtrace::_print_fmt
             at src/libstd/sys_common/backtrace.rs:77
   3: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
             at src/libstd/sys_common/backtrace.rs:61
   4: core::fmt::write
             at src/libcore/fmt/mod.rs:1030
   5: std::io::Write::write_fmt
             at src/libstd/io/mod.rs:1412
   6: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:65
   7: std::sys_common::backtrace::print
             at src/libstd/sys_common/backtrace.rs:50
   8: std::panicking::default_hook::{{closure}}
             at src/libstd/panicking.rs:200
   9: std::panicking::default_hook
             at src/libstd/panicking.rs:214
  10: rustc::util::common::panic_hook
  11: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:481
  12: std::panicking::continue_panic_fmt
             at src/libstd/panicking.rs:384
  13: rust_begin_unwind
             at src/libstd/panicking.rs:311
  14: core::panicking::panic_fmt
             at src/libcore/panicking.rs:85
  15: core::panicking::panic_bounds_check
             at src/libcore/panicking.rs:61
  16: <clippy_lints::misc_early::MiscEarlyLints as rustc::lint::EarlyLintPass>::check_expr
  17: <rustc::lint::context::EarlyLintPassObjects as rustc::lint::EarlyLintPass>::check_expr
  18: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_expr
  19: syntax::visit::walk_expr
  20: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_expr
  21: syntax::visit::walk_expr
  22: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_expr
  23: syntax::visit::walk_fn
  24: syntax::visit::walk_impl_item
  25: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_impl_item
  26: syntax::visit::walk_item
  27: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_item
  28: syntax::visit::walk_item
  29: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_item
  30: syntax::visit::walk_item
  31: <rustc::lint::context::EarlyContextAndPass<T> as syntax::visit::Visitor>::visit_item
  32: syntax::visit::walk_crate
  33: rustc::lint::context::early_lint_crate
  34: rustc::lint::context::check_ast_crate
  35: rustc::util::common::time
  36: rustc_interface::passes::BoxedResolver::access::{{closure}}
  37: rustc_interface::passes::configure_and_expand::{{closure}}
  38: rustc_data_structures::box_region::PinnedGenerator<I,A,R>::access
  39: rustc_interface::queries::Query<T>::compute
  40: rustc_interface::queries::Query<T>::compute
  41: rustc_interface::queries::<impl rustc_interface::interface::Compiler>::prepare_outputs
  42: rustc_interface::interface::run_compiler_in_existing_thread_pool
  43: std::thread::local::LocalKey<T>::with
  44: scoped_tls::ScopedKey<T>::set
  45: syntax::with_globals
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
query stack during panic:
end of query stack

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/blob/master/CONTRIBUTING.md#bug-reports

note: rustc 1.39.0-nightly (eb48d6bde 2019-09-12) running on x86_64-unknown-linux-gnu

The package compiles fine out of RLS

[flip1995]

Does it also pass when you run cargo clippy (not cargo build) on the project? If so, could you share the version of Clippy (cargo clippy --version)?

I it crashes while running cargo clippy, the crate name should be displayed.

[flip1995]

As a sitenote: a similar issue (#4480) was fixed in #4486. But the nightly 2019-09-12 includes this fix. So maybe something else is broken.

[JohnTitor]

@arturoc Could you check if latest nightly's Clippy fixes your issue?

[arturoc]

sorry don't remember how i worked around this issue or if it was fixed at some point but i haven't seen this problem in latest versions so i'll assume it was fixed. i'll close this and report back if i ever found this again.

Thanks!