Remove doc_cfg_hide feature

Author: GuillaumeGomez

compiler/rustc_feature/src/unstable.rs

@@ -473,8 +473,6 @@ declare_features! (
     (unstable, doc_auto_cfg, "1.58.0", Some(43781)),
     /// Allows `#[doc(cfg(...))]`.
     (unstable, doc_cfg, "1.21.0", Some(43781)),
-    /// Allows `#[doc(cfg_hide(...))]`.
-    (unstable, doc_cfg_hide, "1.57.0", Some(43781)),
     /// Allows `#[doc(masked)]`.
     (unstable, doc_masked, "1.21.0", Some(44027)),
     /// Allows `dyn* Trait` objects.

compiler/rustc_span/src/symbol.rs

@@ -841,7 +841,6 @@ symbols! {
         doc_alias,
         doc_auto_cfg,
         doc_cfg,
-        doc_cfg_hide,
         doc_keyword,
         doc_masked,
         doc_notable_trait,

library/alloc/src/lib.rs

@@ -204,7 +204,7 @@
 //
 // Rustdoc features:
 #![feature(doc_cfg)]
-#![feature(doc_cfg_hide)]
+#![cfg_attr(bootstrap, feature(doc_cfg_hide))]
 // Technically, this is a bug in rustdoc: rustdoc sees the documentation on `#[lang = slice_alloc]`
 // blocks is for `&[T]`, which also has documentation using this feature in `core`, and gets mad
 // that the feature-gate isn't enabled. Ideally, it wouldn't check for the feature gate for docs

library/core/src/lib.rs

@@ -159,6 +159,7 @@
 //
 // Language features:
 // tidy-alphabetical-start
+#![cfg_attr(bootstrap, feature(doc_cfg_hide))]
 #![feature(abi_unadjusted)]
 #![feature(adt_const_params)]
 #![feature(allow_internal_unsafe)]
@@ -173,7 +174,6 @@
 #![feature(decl_macro)]
 #![feature(deprecated_suggestion)]
 #![feature(doc_cfg)]
-#![feature(doc_cfg_hide)]
 #![feature(doc_notable_trait)]
 #![feature(extern_types)]
 #![feature(f128)]

library/std/src/lib.rs

@@ -279,6 +279,8 @@
 // tidy-alphabetical-start
 
 // stabilization was reverted after it hit beta
+#![cfg_attr(bootstrap, feature(doc_cfg_hide))]
+#![cfg_attr(not(bootstrap), feature(autodiff))]
 #![feature(alloc_error_handler)]
 #![feature(allocator_internals)]
 #![feature(allow_internal_unsafe)]
@@ -294,7 +296,6 @@
 #![feature(decl_macro)]
 #![feature(deprecated_suggestion)]
 #![feature(doc_cfg)]
-#![feature(doc_cfg_hide)]
 #![feature(doc_masked)]
 #![feature(doc_notable_trait)]
 #![feature(dropck_eyepatch)]