diff --git a/compiler/rustc_arena/src/lib.rs b/compiler/rustc_arena/src/lib.rs
index 5151c358774e..a0350dd6ff31 100644
--- a/compiler/rustc_arena/src/lib.rs
+++ b/compiler/rustc_arena/src/lib.rs
@@ -10,7 +10,6 @@
 // tidy-alphabetical-start
 #![allow(clippy::mut_from_ref)] // Arena allocators are one place where this pattern is fine.
 #![allow(internal_features)]
-#![cfg_attr(bootstrap, feature(maybe_uninit_slice))]
 #![cfg_attr(test, feature(test))]
 #![deny(unsafe_op_in_unsafe_fn)]
 #![doc(test(no_crate_inject, attr(deny(warnings), allow(internal_features))))]
diff --git a/compiler/rustc_codegen_llvm/src/lib.rs b/compiler/rustc_codegen_llvm/src/lib.rs
index 4d0f8dbb9302..65e1bc5c8434 100644
--- a/compiler/rustc_codegen_llvm/src/lib.rs
+++ b/compiler/rustc_codegen_llvm/src/lib.rs
@@ -5,7 +5,6 @@
 //! This API is completely unstable and subject to change.
 
 // tidy-alphabetical-start
-#![cfg_attr(bootstrap, feature(slice_as_array))]
 #![feature(assert_matches)]
 #![feature(extern_types)]
 #![feature(file_buffered)]
diff --git a/compiler/rustc_hir/src/lib.rs b/compiler/rustc_hir/src/lib.rs
index 7a5776f0d5a9..7c9c15c16df4 100644
--- a/compiler/rustc_hir/src/lib.rs
+++ b/compiler/rustc_hir/src/lib.rs
@@ -3,7 +3,6 @@
 //! [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/hir.html
 
 // tidy-alphabetical-start
-#![cfg_attr(bootstrap, feature(debug_closure_helpers))]
 #![feature(associated_type_defaults)]
 #![feature(closure_track_caller)]
 #![feature(const_default)]
diff --git a/compiler/rustc_hir_analysis/src/lib.rs b/compiler/rustc_hir_analysis/src/lib.rs
index 538fb8c7df1e..65f6a11e8e9b 100644
--- a/compiler/rustc_hir_analysis/src/lib.rs
+++ b/compiler/rustc_hir_analysis/src/lib.rs
@@ -58,7 +58,6 @@ This API is completely unstable and subject to change.
 // tidy-alphabetical-start
 #![allow(rustc::diagnostic_outside_of_impl)]
 #![allow(rustc::untranslatable_diagnostic)]
-#![cfg_attr(bootstrap, feature(debug_closure_helpers))]
 #![feature(assert_matches)]
 #![feature(gen_blocks)]
 #![feature(if_let_guard)]
diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs
index 810760e9f53e..e2a061cab680 100644
--- a/compiler/rustc_lint/src/builtin.rs
+++ b/compiler/rustc_lint/src/builtin.rs
@@ -2683,7 +2683,6 @@ declare_lint! {
     ///
     /// ```rust,compile_fail
     /// # #![allow(unused)]
-    /// # #![cfg_attr(bootstrap, deny(deref_nullptr))]
     /// use std::ptr;
     /// unsafe {
     ///     let x = &*ptr::null::<i32>();
diff --git a/compiler/rustc_lint_defs/src/builtin.rs b/compiler/rustc_lint_defs/src/builtin.rs
index 99cce0c44b86..6bd0efd5d751 100644
--- a/compiler/rustc_lint_defs/src/builtin.rs
+++ b/compiler/rustc_lint_defs/src/builtin.rs
@@ -2346,8 +2346,7 @@ declare_lint! {
     /// [sanitize]: https://doc.rust-lang.org/nightly/unstable-book/language-features/no-sanitize.html
     /// ### Example
     ///
-    #[cfg_attr(bootstrap, doc = "```ignore")]
-    #[cfg_attr(not(bootstrap), doc = "```rust,no_run")]
+    /// ```rust,no_run
     /// #![feature(sanitize)]
     ///
     /// #[sanitize(realtime = "nonblocking")]
@@ -2356,8 +2355,7 @@ declare_lint! {
     /// fn main() {
     ///     x();
     /// }
-    #[cfg_attr(bootstrap, doc = "```")]
-    #[cfg_attr(not(bootstrap), doc = "```")]
+    /// ```
     ///
     /// {{produces}}
     ///
@@ -4907,8 +4905,7 @@ declare_lint! {
     ///
     /// ### Example
     ///
-    #[cfg_attr(bootstrap, doc = "```ignore")]
-    #[cfg_attr(not(bootstrap), doc = "```rust,compile_fail")]
+    /// ```rust,compile_fail
     /// #![feature(supertrait_item_shadowing)]
     /// #![deny(resolving_to_items_shadowing_supertrait_items)]
     ///
@@ -4924,8 +4921,7 @@ declare_lint! {
     ///
     /// struct MyType;
     /// MyType.hello();
-    #[cfg_attr(bootstrap, doc = "```")]
-    #[cfg_attr(not(bootstrap), doc = "```")]
+    /// ```
     ///
     /// {{produces}}
     ///
@@ -4951,8 +4947,7 @@ declare_lint! {
     ///
     /// ### Example
     ///
-    #[cfg_attr(bootstrap, doc = "```ignore")]
-    #[cfg_attr(not(bootstrap), doc = "```rust,compile_fail")]
+    /// ```rust,compile_fail"
     /// #![feature(supertrait_item_shadowing)]
     /// #![deny(shadowing_supertrait_items)]
     ///
@@ -4965,8 +4960,7 @@ declare_lint! {
     ///     fn hello(&self) {}
     /// }
     /// impl<T> Downstream for T {}
-    #[cfg_attr(bootstrap, doc = "```")]
-    #[cfg_attr(not(bootstrap), doc = "```")]
+    /// ```
     ///
     /// {{produces}}
     ///
diff --git a/compiler/rustc_target/src/lib.rs b/compiler/rustc_target/src/lib.rs
index 1210169b3a5c..dfa1b2320718 100644
--- a/compiler/rustc_target/src/lib.rs
+++ b/compiler/rustc_target/src/lib.rs
@@ -8,7 +8,6 @@
 //! LLVM.
 
 // tidy-alphabetical-start
-#![cfg_attr(bootstrap, feature(debug_closure_helpers))]
 #![expect(internal_features)]
 #![feature(iter_intersperse)]
 #![feature(rustc_attrs)]
diff --git a/library/proc_macro/src/lib.rs b/library/proc_macro/src/lib.rs
index 9287807c43e3..a0b6656c8ded 100644
--- a/library/proc_macro/src/lib.rs
+++ b/library/proc_macro/src/lib.rs
@@ -22,7 +22,6 @@
 #![feature(staged_api)]
 #![feature(allow_internal_unstable)]
 #![feature(decl_macro)]
-#![cfg_attr(bootstrap, feature(maybe_uninit_write_slice))]
 #![feature(negative_impls)]
 #![feature(panic_can_unwind)]
 #![feature(restricted_std)]
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index c74c556b6210..137319ae0c06 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -1,5 +1,4 @@
 // tidy-alphabetical-start
-#![cfg_attr(bootstrap, feature(debug_closure_helpers))]
 #![doc(
     html_root_url = "https://doc.rust-lang.org/nightly/",
     html_playground_url = "https://play.rust-lang.org/"
diff --git a/src/tools/miri/src/lib.rs b/src/tools/miri/src/lib.rs
index 743caed6dbb6..7ce2ab3b3a43 100644
--- a/src/tools/miri/src/lib.rs
+++ b/src/tools/miri/src/lib.rs
@@ -17,7 +17,6 @@
 #![feature(derive_coerce_pointee)]
 #![feature(arbitrary_self_types)]
 #![feature(iter_advance_by)]
-#![cfg_attr(bootstrap, feature(duration_from_nanos_u128))]
 // Configure clippy and other lints
 #![allow(
     clippy::collapsible_else_if,