Compiler panic when running 'cargo check' with missing crate

[dbrgn]

With both current stable and nightly...

$ rustup update nightly
$ rustup override set nightly
$ rustc --version
rustc 1.17.0-nightly (8c4f2c64c 2017-03-22)

...when compiling this crate...

[package]
name = "crash"
version = "0.1.0"

[dependencies]
diesel = { version = "0.11.0", features = ["postgres", "chrono"] }
diesel_codegen = { version = "0.11.0", features = ["postgres"] }

// src/main.rs
#[macro_use] extern crate diesel;
#[macro_use] extern crate diesel_codegen;
extern crate chrono;

use chrono::{DateTime, UTC};

#[derive(Queryable, Debug)]
struct Foo {
    bar: u32,
    date: DateTime<UTC>,
}

fn main() {
    println!("Hello, world!");
}

...the compiler crashes on cargo check:

$ cargo check
   Compiling crash v0.1.0 (file:///tmp/crash)
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

thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', /checkout/src/libcore/option.rs:329
note: Run with `RUST_BACKTRACE=1` for a backtrace.

error: Could not compile `crash`.

To learn more, run the command again with --verbose.

Here's the backtrace:

thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', /checkout/src/libcore/option.rs:329
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
stack backtrace:
   0: rustc_metadata::creader::CrateLoader::resolve_crate
   1: <rustc_metadata::creader::CrateLoader<'a> as rustc::middle::cstore::CrateLoader>::process_item
   2: rustc_resolve::build_reduced_graph::<impl rustc_resolve::Resolver<'a>>::build_reduced_graph_for_item
   3: <rustc_resolve::build_reduced_graph::BuildReducedGraphVisitor<'a, 'b> as syntax::visit::Visitor<'a>>::visit_item
   4: <rustc_resolve::build_reduced_graph::BuildReducedGraphVisitor<'a, 'b> as syntax::visit::Visitor<'a>>::visit_item
   5: rustc_resolve::macros::<impl syntax::ext::base::Resolver for rustc_resolve::Resolver<'a>>::visit_expansion
   6: syntax::ext::expand::MacroExpander::collect_invocations
   7: syntax::ext::expand::MacroExpander::expand
   8: syntax::ext::expand::MacroExpander::expand_crate
   9: rustc_driver::driver::phase_2_configure_and_expand::{{closure}}
  10: rustc_driver::driver::phase_2_configure_and_expand
  11: rustc_driver::driver::compile_input
  12: rustc_driver::run_compiler
  13: std::panicking::try::do_call
  14: __rust_maybe_catch_panic
             at /checkout/src/libpanic_unwind/lib.rs:98
  15: <F as alloc::boxed::FnBox<A>>::call_box
  16: std::sys::imp::thread::Thread::new::thread_start
             at /checkout/src/liballoc/boxed.rs:650
             at /checkout/src/libstd/sys_common/thread.rs:21
             at /checkout/src/libstd/sys/unix/thread.rs:84
  17: start_thread
  18: clone

The problem does not happen when using cargo run:

$ cargo run
   Compiling crash v0.1.0 (file:///tmp/crash)
error[E0463]: can't find crate for `chrono`
 --> src/main.rs:3:1
  |
3 | extern crate chrono;
  | ^^^^^^^^^^^^^^^^^^^^ can't find crate

error: aborting due to previous error

error: Could not compile `crash`.

Might be related to #40755.

[abonander]

Should have been fixed with #40542, please try again with a newer nightly (when one is available) and let me know if it still happens.

[dbrgn]

@abonander just tested it on current nightly (3da4023 2017-03-24), bug seems fixed! Thank you! ✨

[mkollaro]

I got this issue with cargo check on stable Rust. I was removing a dependency, but forgot to delete extern crate X from main.rs, while I already deleted it from Cargo.toml. The cargo check command panics because of this, but cargo build doesn't have the issue and correctly complained that I don't have crate X.

Using rustc 1.16.0 (30cf806 2017-03-10) and cargo-0.17.0-nightly (f9e5481 2017-03-03).

thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libcore/option.rs:323
stack backtrace:
   1:     0x7f8643d0540c - std::sys::imp::backtrace::tracing::imp::write::hf33ae72d0baa11ed
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:42
   2:     0x7f8643d139ae - std::panicking::default_hook::{{closure}}::h59672b733cc6a455
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/panicking.rs:351
   3:     0x7f8643d13553 - std::panicking::default_hook::h1670459d2f3f8843
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/panicking.rs:361
   4:     0x7f8643d13e4b - std::panicking::rust_panic_with_hook::hcf0ddb069e7beee7
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/panicking.rs:555
   5:     0x7f8643d13ce4 - std::panicking::begin_panic::hd6eb68e27bdf6140
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/panicking.rs:517
   6:     0x7f8643d13c09 - std::panicking::begin_panic_fmt::hfea5965948b877f8
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/panicking.rs:501
   7:     0x7f8643d13b97 - rust_begin_unwind
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/panicking.rs:477
   8:     0x7f8643d50edd - core::panicking::panic_fmt::hc0f6d7b2c300cdd9
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libcore/panicking.rs:69
   9:     0x7f8643d50e14 - core::panicking::panic::h7abeb5b818ec354e
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libcore/panicking.rs:49
  10:     0x7f86419d8876 - rustc_metadata::creader::CrateLoader::resolve_crate::h6e72600e2dd6f65b
  11:     0x7f86419df98f - <rustc_metadata::creader::CrateLoader<'a> as rustc::middle::cstore::CrateLoader>::process_item::h3593d13570805f47
  12:     0x7f86411ff8b0 - rustc_resolve::build_reduced_graph::<impl rustc_resolve::Resolver<'a>>::build_reduced_graph_for_item::h3cc2f08d7828c563
  13:     0x7f864120667f - <rustc_resolve::build_reduced_graph::BuildReducedGraphVisitor<'a, 'b> as syntax::visit::Visitor<'a>>::visit_item::h775ca4c5a23a8667
  14:     0x7f8641206b7f - <rustc_resolve::build_reduced_graph::BuildReducedGraphVisitor<'a, 'b> as syntax::visit::Visitor<'a>>::visit_item::h775ca4c5a23a8667
  15:     0x7f86411fa5bf - rustc_resolve::macros::<impl syntax::ext::base::Resolver for rustc_resolve::Resolver<'a>>::visit_expansion::hc836a3e7268abdbf
  16:     0x7f863d69877a - syntax::ext::expand::MacroExpander::collect_invocations::h32417ac98c0c9be1
  17:     0x7f863d697140 - syntax::ext::expand::MacroExpander::expand::h695353fd58aabfd3
  18:     0x7f863d696ba5 - syntax::ext::expand::MacroExpander::expand_crate::h9811866201c8237a
  19:     0x7f86440a00dc - rustc_driver::driver::phase_2_configure_and_expand::{{closure}}::h231d639b5d33e30c
  20:     0x7f86440977f5 - rustc_driver::driver::phase_2_configure_and_expand::hd9965365e42d7a90
  21:     0x7f864409043a - rustc_driver::driver::compile_input::hd9f060ee16a643fb
  22:     0x7f86440dc844 - rustc_driver::run_compiler::h762802568c0e140e
  23:     0x7f8643fe8edb - std::panicking::try::do_call::h935e2f773deaf841
  24:     0x7f8643d1cc8a - __rust_maybe_catch_panic
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libpanic_unwind/lib.rs:98
  25:     0x7f8644011112 - <F as alloc::boxed::FnBox<A>>::call_box::he43811d1f6894655
  26:     0x7f8643d12804 - std::sys::imp::thread::Thread::new::thread_start::he668872ac11287ba
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/liballoc/boxed.rs:624
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/sys_common/thread.rs:21
                        at /buildslave/rust-buildbot/slave/stable-dist-rustc-linux/build/src/libstd/sys/unix/thread.rs:84
  27:     0x7f863c7d0183 - start_thread
  28:     0x7f86439c037c - clone
  29:                0x0 - <unknown>

[dbrgn]

@mkollaro try upgrading to nightly 2017-03-24 (rustup update nightly).

[mkollaro]

Got fixed 5 seconds before I added my comment...well it doesn't really trouble me, I can use cargo check once I remove the extern crate that shouldn't have been there.

For those who hit against this issue before it lands in stable: just run cargo build, fix the error, then run cargo check again.