Stabilize naked_functions

This stabilizes the feature described in RFC 2972,
which supersedes the earlier RFC 1201.

Closes #32408
Closes #90957

Author: bstrie

compiler/rustc_error_codes/src/error_codes/E0787.md

@@ -3,8 +3,6 @@ An unsupported naked function definition.
 Erroneous code example:
 
 ```compile_fail,E0787
-#![feature(naked_functions)]
-
 #[naked]
 pub extern "C" fn f() -> u32 {
     42

compiler/rustc_feature/src/accepted.rs

@@ -203,6 +203,8 @@ declare_features! (
     /// Allows patterns with concurrent by-move and by-ref bindings.
     /// For example, you can write `Foo(a, ref b)` where `a` is by-move and `b` is by-ref.
     (accepted, move_ref_pattern, "1.49.0", Some(68354), None),
+    /// Allows using `#[naked]` on functions.
+    (accepted, naked_functions, "1.60.0", Some(90957), None),
     /// Allows using `#![no_std]`.
     (accepted, no_std, "1.6.0", None, None),
     /// Allows defining identifiers beyond ASCII.

compiler/rustc_feature/src/active.rs

@@ -435,8 +435,6 @@ declare_features! (
     (active, more_qualified_paths, "1.54.0", Some(86935), None),
     /// Allows the `#[must_not_suspend]` attribute.
     (active, must_not_suspend, "1.57.0", Some(83310), None),
-    /// Allows using `#[naked]` on functions.
-    (active, naked_functions, "1.9.0", Some(32408), None),
     /// Allows specifying modifiers in the link attribute: `#[link(modifiers = "...")]`
     (active, native_link_modifiers, "1.53.0", Some(81490), None),
     /// Allows specifying the as-needed link modifier

compiler/rustc_feature/src/builtin_attrs.rs

@@ -360,6 +360,7 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
     // Code generation:
     ungated!(inline, Normal, template!(Word, List: "always|never"), FutureWarnFollowing),
     ungated!(cold, Normal, template!(Word), WarnFollowing),
+    ungated!(naked, Normal, template!(Word), WarnFollowing),
     ungated!(no_builtins, CrateLevel, template!(Word), WarnFollowing),
     ungated!(target_feature, Normal, template!(List: r#"enable = "name""#), DuplicatesOk),
     ungated!(track_caller, Normal, template!(Word), WarnFollowing),
@@ -379,7 +380,6 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
     // ==========================================================================
 
     // Linking:
-    gated!(naked, Normal, template!(Word), WarnFollowing, naked_functions, experimental!(naked)),
     gated!(
         link_ordinal, Normal, template!(List: "ordinal"), ErrorPreceding, raw_dylib,
         experimental!(link_ordinal)

compiler/rustc_lint_defs/src/builtin.rs

@@ -2745,8 +2745,6 @@ declare_lint! {
     /// ### Example
     ///
     /// ```rust
-    /// #![feature(naked_functions)]
-    ///
     /// use std::arch::asm;
     ///
     /// #[naked]

src/doc/unstable-book/src/compiler-flags/sanitizer.md

@@ -199,8 +199,6 @@ LLVM CFI can be enabled with -Zsanitizer=cfi and requires LTO (i.e., -Clto).
 ## Example
 
 ```text
-#![feature(naked_functions)]
-
 use std::arch::asm;
 use std::mem;
 

src/test/codegen/naked-functions.rs

@@ -3,7 +3,7 @@
 // only-x86_64
 
 #![crate_type = "lib"]
-#![feature(naked_functions)]
+
 use std::arch::asm;
 
 // CHECK: Function Attrs: naked

src/test/codegen/naked-noinline.rs

@@ -2,8 +2,8 @@
 // compile-flags: -O -Zmir-opt-level=3
 // needs-asm-support
 // ignore-wasm32
+
 #![crate_type = "lib"]
-#![feature(naked_functions)]
 
 use std::arch::asm;
 

src/test/ui/asm/naked-functions-ffi.rs

@@ -1,6 +1,6 @@
 // check-pass
 // needs-asm-support
-#![feature(naked_functions)]
+
 #![crate_type = "lib"]
 
 use std::arch::asm;

src/test/ui/asm/naked-functions-unused.rs

@@ -1,8 +1,8 @@
 // revisions: x86_64 aarch64
 //[x86_64] only-x86_64
 //[aarch64] only-aarch64
+
 #![deny(unused)]
-#![feature(naked_functions)]
 #![crate_type = "lib"]
 
 pub trait Trait {