Tracking Issue for -Z crate-attr

This is a tracking issue for the -Z crate-attr unstable option (RFC 3791).

About tracking issues

Tracking issues are used to record the overall progress of implementation.
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Steps

• Adjust documentation (see instructions on rustc-dev-guide)
• Stabilization PR (see instructions on rustc-dev-guide)

Unresolved Questions

• this likely needs an RFC, since it landed without much discussion? i am tentatively planning to do this at the same time as an RFC for #![register_tool].
• probably we will want to limit the syntax? for example, -Z crate-attr='crate_name= /* foo */ "test"' is currently accepted without warning, and -Z crate-attr='crate_name=/*' gives an error about an unterminated block comment. explicitly rejected by the RFC
• fix interactions with doctests: https://github.com/rust-lang/rust/issues/138491
• we should improve diagnostics; currently we treat the attribute as surrounded by #![ /*...*/ ], but don't show the surrounding code in the error:

; rustc src/main.rs -Z crate-attr='#![crate_name="test"]'
error: expected identifier, found `#`
 --> <crate attribute>:1:1
  |
1 | #![crate_name="test"]
  | ^ expected identifier

• fix lint controls to desugar to crate-attr, as described in the RFC
• test that editions and file!/line!/column! behave as specified in the RFC

Implementation history

• Initial implementation: https://github.com/rust-lang/rust/pull/52355
• Recommended in other diagnostics: https://github.com/rust-lang/rust/pull/114959
• Documentation and tests: https://github.com/rust-lang/rust/pull/138288
• Improve diagnostics for crate-attr itself: https://github.com/rust-lang/rust/pull/138336
• Fix rustdoc support: https://github.com/rust-lang/rust/pull/147292
• Additional tests: https://github.com/rust-lang/rust/pull/160145

Read RFC 3791 and the rustc-dev-guide instructions linked in the checklist, then review the remaining lint-control and edition/file!/line!/column! requirements. Done means those behaviors are tested, the documentation is updated, and a stabilization PR is prepared.