diff --git a/src/doc/unstable-book/src/language-features/rustc-private.md b/src/doc/unstable-book/src/language-features/rustc-private.md index 97fce5980e40b..3b83a3cf4df8a 100644 --- a/src/doc/unstable-book/src/language-features/rustc-private.md +++ b/src/doc/unstable-book/src/language-features/rustc-private.md @@ -6,6 +6,9 @@ The tracking issue for this feature is: [#27812] ------------------------ -This feature allows access to unstable internal compiler crates. +This feature allows access to unstable internal compiler crates such as `rustc_driver`. -Additionally it changes the linking behavior of crates which have this feature enabled. It will prevent linking to a dylib if there's a static variant of it already statically linked into another dylib dependency. This is required to successfully link to `rustc_driver`. +The presence of this feature changes the way the linkage format for dylibs is calculated in a way +that is necessary for linking against dylibs that statically link `std` (such as `rustc_driver`). +This makes this feature "viral" in linkage; its use in a given crate makes its use required in +dependent crates which link to it (including integration tests, which are built as separate crates).