Auto merge of rust-lang#73032 - yoshuawuyts:stabilize-leading_trailing_ones, r=Amanieu

stabilize leading_trailing_ones

This PR stabilizes the `leading_trailing_ones` feature. It's been available on nightly since the start of the year, and hasn't had any issues since. It seems unlikely we'll want to change this, so following up on @djc's suggestion in rust-lang#57969 (comment) I'd like to put forward this PR to stabilize the feature and make it part of `1.46.0`. Thanks!

cc/ @djc @rust-lang/libs

Author: bors

src/libcore/num/mod.rs

@@ -457,13 +457,13 @@ $EndFeature, "
 Basic usage:
 
 ```
-", $Feature, "#![feature(leading_trailing_ones)]
-let n = -1", stringify!($SelfT), ";
+", $Feature, "let n = -1", stringify!($SelfT), ";
 
 assert_eq!(n.leading_ones(), ", stringify!($BITS), ");",
 $EndFeature, "
 ```"),
-            #[unstable(feature = "leading_trailing_ones", issue = "57969")]
+            #[stable(feature = "leading_trailing_ones", since = "1.46.0")]
+            #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")]
             #[inline]
             pub const fn leading_ones(self) -> u32 {
                 (self as $UnsignedT).leading_ones()
@@ -478,13 +478,13 @@ $EndFeature, "
 Basic usage:
 
 ```
-", $Feature, "#![feature(leading_trailing_ones)]
-let n = 3", stringify!($SelfT), ";
+", $Feature, "let n = 3", stringify!($SelfT), ";
 
 assert_eq!(n.trailing_ones(), 2);",
 $EndFeature, "
 ```"),
-            #[unstable(feature = "leading_trailing_ones", issue = "57969")]
+            #[stable(feature = "leading_trailing_ones", since = "1.46.0")]
+            #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")]
             #[inline]
             pub const fn trailing_ones(self) -> u32 {
                 (self as $UnsignedT).trailing_ones()
@@ -2695,12 +2695,12 @@ assert_eq!(n.trailing_zeros(), 3);", $EndFeature, "
 Basic usage:
 
 ```
-", $Feature, "#![feature(leading_trailing_ones)]
-let n = !(", stringify!($SelfT), "::MAX >> 2);
+", $Feature, "let n = !(", stringify!($SelfT), "::MAX >> 2);
 
 assert_eq!(n.leading_ones(), 2);", $EndFeature, "
 ```"),
-            #[unstable(feature = "leading_trailing_ones", issue = "57969")]
+            #[stable(feature = "leading_trailing_ones", since = "1.46.0")]
+            #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")]
             #[inline]
             pub const fn leading_ones(self) -> u32 {
                 (!self).leading_zeros()
@@ -2716,12 +2716,12 @@ of `self`.
 Basic usage:
 
 ```
-", $Feature, "#![feature(leading_trailing_ones)]
-let n = 0b1010111", stringify!($SelfT), ";
+", $Feature, "let n = 0b1010111", stringify!($SelfT), ";
 
 assert_eq!(n.trailing_ones(), 3);", $EndFeature, "
 ```"),
-            #[unstable(feature = "leading_trailing_ones", issue = "57969")]
+            #[stable(feature = "leading_trailing_ones", since = "1.46.0")]
+            #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")]
             #[inline]
             pub const fn trailing_ones(self) -> u32 {
                 (!self).trailing_zeros()

src/libcore/tests/lib.rs

@@ -40,7 +40,6 @@
 #![feature(const_raw_ptr_deref)]
 #![feature(never_type)]
 #![feature(unwrap_infallible)]
-#![feature(leading_trailing_ones)]
 #![feature(const_forget)]
 #![feature(option_unwrap_none)]
 #![feature(peekable_next_if)]