Rust-clippy: `clippy-driver` crashes without arguments (index out of bounds)

[ashemedai]

Ran clippy-driver without parameters and got an ICE.

I tried this code:

clippy-driver

I expected to see this happen: See some help output

Instead, this happened: received an ICE

Meta

rustc --version --verbose:

% rustc --version --verbose
rustc 1.38.0 (625451e37 2019-09-23)
binary: rustc
commit-hash: 625451e376bb2e5283fc4741caa0a3e8a2ca4d54
commit-date: 2019-09-23
host: x86_64-apple-darwin
release: 1.38.0
LLVM version: 9.0

% cargo clippy -V
clippy 0.0.212 (3aea8603 2019-09-03)

Backtrace:

% RUST_BACKTRACE=1 clippy-driver
thread 'main' panicked at 'index out of bounds: the len is 1 but the index is 1', /rustc/625451e376bb2e5283fc4741caa0a3e8a2ca4d54/src/libcore/slice/mod.rs:2715:10
stack backtrace:
   0: std::panicking::default_hook::{{closure}}
   1: std::panicking::default_hook
   2: std::panicking::rust_panic_with_hook
   3: std::panicking::continue_panic_fmt
   4: rust_begin_unwind
   5: core::panicking::panic_fmt
   6: core::panicking::panic_bounds_check
   7: <std::panic::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once
   8: std::panicking::try::do_call
   9: __rust_maybe_catch_panic
  10: rustc_driver::report_ices_to_stderr_if_any
  11: clippy_driver::main
  12: std::rt::lang_start::{{closure}}
  13: std::panicking::try::do_call
  14: __rust_maybe_catch_panic
  15: std::rt::lang_start_internal
  16: main

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 1.38.0 (625451e37 2019-09-23) running on x86_64-apple-darwin

[phansch]

Could you try running the command with RUST_BACKTRACE=full as well? That should give a bit more information. If possible, could you also provide the source code where this crash happens?

[mati865]

@phansch it crashes without any code. It's not a lint but rather clippy-driver binary what crashes here.

[mati865]

It must be this line: https://github.com/rust-lang/rust-clippy/blob/1d0f62570b2f58b09b991f7312dd1f1564c613f0/src/driver.rs#L302

[ashemedai]

What @mati865 says, just running it in an empty directory without any arguments. I can get you a full backtrace tomorrow morning, as needed.

[llogiq]

Yeah, we should probably check if there is any arg in orig_args and issue some usage info otherwise.

[ashemedai]

Full backtrace:

% RUST_BACKTRACE=full clippy-driver
thread 'main' panicked at 'index out of bounds: the len is 1 but the index is 1', /rustc/625451e376bb2e5283fc4741caa0a3e8a2ca4d54/src/libcore/slice/mod.rs:2715:10
stack backtrace:
   0:        0x10b3f5c92 - std::panicking::default_hook::{{closure}}::h3f994bbc901f9889
   1:        0x10b3f595d - std::panicking::default_hook::h6c261b7dad1af707
   2:        0x10b3f6470 - std::panicking::rust_panic_with_hook::hd3c20890ac648923
   3:        0x10b3f5fad - std::panicking::continue_panic_fmt::hf444d349a369432b
   4:        0x10b3f5e99 - rust_begin_unwind
   5:        0x10b421c12 - core::panicking::panic_fmt::h7bf9e431fd27d405
   6:        0x10b421bc9 - core::panicking::panic_bounds_check::h945cc15e7a0d27ba
   7:        0x10ad9f3b3 - <std::panic::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once::hd67d0aeef970b729
   8:        0x10ad8f15e - std::panicking::try::do_call::h11c6ee48236c5b67
   9:        0x10b4057cf - __rust_maybe_catch_panic
  10:        0x10ad88e12 - rustc_driver::report_ices_to_stderr_if_any::h67c06ffbfebe6f4c
  11:        0x10ad9ca9e - clippy_driver::main::h2220a55246cb76db
  12:        0x10ad8f146 - std::rt::lang_start::{{closure}}::h61b9bee55274c3f2
  13:        0x10b3f5e18 - std::panicking::try::do_call::h8ffcb2a43dbb732c
  14:        0x10b4057cf - __rust_maybe_catch_panic
  15:        0x10b3f68ee - std::rt::lang_start_internal::ha688fd553625ef6f
  16:        0x10ad9cad9 - main

error: internal compiler error: unexpected panic