bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Rollup merge of #138844 - petrochenkov:cfgtrace2, r=nnethercote

Browse source 
expand: Leave traces when expanding `cfg` attributes

This is the same as https://github.com/rust-lang/rust/pull/138515, but for `cfg(true)` instead of `cfg_attr`.

The difference is that `cfg(true)`s already left "traces" after themselves - the `cfg` attributes themselves, with `expanded_inert_attrs` set to true, with full tokens, available to proc macros.
This is not a reasonably expected behavior, but it could not be removed without a replacement, because a [major rustdoc feature](https://github.com/rust-lang/rfcs/pull/3631) and a number of clippy lints rely on it. This PR implements a replacement.

This needs a crater run, because it changes observable behavior (in an intended way) - proc macros can no longer see expanded `cfg(true)` attributes.

(Some minor unnecessary special casing for `sym::cfg_attr` is also removed in this PR.)

r? `@nnethercote`
This commit is contained in:
Jacob Pratt 2025-03-27 13:11:17 -04:00 • committed by GitHub
commit 3a8621d681
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
24 changed files with 88 additions and 108 deletions
Download patch file Download diff file Expand all files Collapse all files

2
compiler/rustc_query_system/src/ich/mod.rs
View file

@ -8,7 +8,7 @@ mod hcx;
mod impls_syntax;
pub const IGNORED_ATTRIBUTES: &[Symbol] = &[
sym::cfg,
sym::cfg_trace, // FIXME should this really be ignored?
sym::rustc_if_this_changed,
sym::rustc_then_this_would_need,
sym::rustc_dirty,