diff --git a/src/doc/src/reference/build-scripts.md b/src/doc/src/reference/build-scripts.md index ee2416817b5..1f1fd0041dc 100644 --- a/src/doc/src/reference/build-scripts.md +++ b/src/doc/src/reference/build-scripts.md @@ -258,12 +258,16 @@ identifier, the value should be a string. ### `cargo::rustc-check-cfg=CHECK_CFG` {#rustc-check-cfg} +*See the announcement [blog post][check-cfg-blog-post] for more a global view of the feature.* + Add to the list of expected config names and values that is used when checking the _reachable_ cfg expressions. For details on the syntax of `CHECK_CFG`, see `rustc` [`--check-cfg` flag][option-check-cfg]. See also the [`unexpected_cfgs`][unexpected-cfgs] lint. +> Note: `cargo:rustc-check-cfg` (single-colon) can be used if your MSRV is below Rust 1.77 + The instruction can be used like this: ```rust,no_run @@ -288,7 +292,13 @@ if foo_bar_condition { } ``` +For a more complete example see in the [build script examples][build-script-examples] page +the [conditional compilation][conditional-compilation-example] example. + +[check-cfg-blog-post]: https://blog.rust-lang.org/2024/05/06/check-cfg.html [option-check-cfg]: ../../rustc/command-line-arguments.md#option-check-cfg +[build-script-examples]: build-script-examples.md +[conditional-compilation-example]: build-script-examples.md#conditional-compilation ### `cargo::rustc-env=VAR=VALUE` {#rustc-env}