`./x doc core` doesn't work

[ChrisDenton]

I tried this:

./x doc core

I expected it to work the same as ./x check core but instead I got the following panic:

thread 'main' panicked at src\bootstrap\src\core\build_steps\compile.rs:416:13:
missing crate for path core

Backtrace

stack backtrace:
   0: std::panicking::begin_panic_handler
             at /rustc/38213856a8a3a6d49a234e0d95a722a4f28a2b18/library\std\src\panicking.rs:692
   1: core::panicking::panic_fmt
             at /rustc/38213856a8a3a6d49a234e0d95a722a4f28a2b18/library\core\src\panicking.rs:75
   2: bootstrap::core::builder::RunConfig::cargo_crates_in_set
             at .\src\bootstrap\src\core\builder\mod.rs:132
   3: bootstrap::core::build_steps::compile::std_crates_for_run_make
             at .\src\bootstrap\src\core\build_steps\compile.rs:416
   4: bootstrap::core::build_steps::doc::impl$7::make_run
             at .\src\bootstrap\src\core\build_steps\doc.rs:582
   5: bootstrap::core::builder::StepDescription::maybe_run
             at .\src\bootstrap\src\core\builder\mod.rs:418
   6: bootstrap::core::builder::StepDescription::run
             at .\src\bootstrap\src\core\builder\mod.rs:548
   7: bootstrap::core::builder::Builder::run_step_descriptions
             at .\src\bootstrap\src\core\builder\mod.rs:1204
   8: bootstrap::core::builder::Builder::execute_cli
             at .\src\bootstrap\src\core\builder\mod.rs:1184
   9: bootstrap::Build::build
             at .\src\bootstrap\src\lib.rs:600
  10: bootstrap::main
             at .\src\bootstrap\src\bin\main.rs:97
  11: core::ops::function::FnOnce::call_once<void (*)(),tuple$<> >
             at /rustc/38213856a8a3a6d49a234e0d95a722a4f28a2b18\library\core\src\ops\function.rs:250
  12: core::hint::black_box
             at /rustc/38213856a8a3a6d49a234e0d95a722a4f28a2b18\library\core\src\hint.rs:475