Remove or allow unused features in library doc and tests

library/alloctests/lib.rs

@@ -16,7 +16,6 @@
 // tidy-alphabetical-start
 #![feature(allocator_api)]
 #![feature(array_into_iter_constructors)]
-#![feature(box_vec_non_null)]
 #![feature(char_internals)]
 #![feature(const_alloc_error)]
 #![feature(const_cmp)]
@@ -55,16 +54,12 @@
 //
 // Language features:
 // tidy-alphabetical-start
-#![feature(cfg_sanitize)]
 #![feature(const_trait_impl)]
 #![feature(dropck_eyepatch)]
-#![feature(lang_items)]
 #![feature(min_specialization)]
-#![feature(negative_impls)]
 #![feature(never_type)]
 #![feature(optimize_attribute)]
 #![feature(prelude_import)]
-#![feature(rustc_allow_const_fn_unstable)]
 #![feature(rustc_attrs)]
 #![feature(staged_api)]
 #![feature(test)]

library/alloctests/tests/lib.rs

@@ -3,7 +3,6 @@
 #![feature(const_heap)]
 #![feature(deque_extend_front)]
 #![feature(iter_array_chunks)]
-#![feature(wtf8_internals)]
 #![feature(cow_is_borrowed)]
 #![feature(core_intrinsics)]
 #![feature(downcast_unchecked)]
@@ -30,8 +29,6 @@
 #![feature(string_remove_matches)]
 #![feature(const_btree_len)]
 #![feature(const_trait_impl)]
-#![feature(panic_update_hook)]
-#![feature(pointer_is_aligned_to)]
 #![feature(test)]
 #![feature(thin_box)]
 #![feature(drain_keep_rest)]

library/core/src/ascii/ascii_char.rs

@@ -878,7 +878,7 @@ pub const fn is_digit(self) -> bool {
     /// # Examples
     ///
     /// ```
-    /// #![feature(ascii_char, ascii_char_variants, is_ascii_octdigit)]
+    /// #![feature(ascii_char, ascii_char_variants)]
     ///
     /// use std::ascii;
     ///

library/core/src/cell.rs

@@ -774,7 +774,6 @@ pub const fn as_slice_of_cells(&self) -> &[Cell<T>] {
 /// following is unsound:
 ///
 /// ```rust
-/// #![feature(cell_get_cloned)]
 /// # use std::cell::Cell;
 ///
 /// #[derive(Copy, Debug)]

library/core/src/convert/num.rs

@@ -219,6 +219,7 @@ fn from(small: bool) -> Self {
     f16;
     doctest_prefix:
     // rustdoc doesn't remove the conventional space after the `///`
+    ///# #![allow(unused_features)]
     ///#![feature(f16)]
     ///# #[cfg(all(target_arch = "x86_64", target_os = "linux"))] {
     ///
@@ -230,6 +231,7 @@ fn from(small: bool) -> Self {
 impl_float_from_bool!(
     f128;
     doctest_prefix:
+    ///# #![allow(unused_features)]
     ///#![feature(f128)]
     ///# #[cfg(all(target_arch = "x86_64", target_os = "linux"))] {
     ///

library/core/src/num/f128.rs

@@ -148,7 +148,10 @@ pub mod consts {
     pub const LN_10: f128 = 2.30258509299404568401799145468436420760110148862877297603333_f128;
 }
 
-#[doc(test(attr(feature(cfg_target_has_reliable_f16_f128), allow(internal_features))))]
+#[doc(test(attr(
+    feature(cfg_target_has_reliable_f16_f128),
+    allow(internal_features, unused_features)
+)))]
 impl f128 {
     /// The radix or base of the internal representation of `f128`.
     #[unstable(feature = "f128", issue = "116909")]
@@ -1470,7 +1473,11 @@ pub const fn algebraic_rem(self, rhs: f128) -> f128 {
 // Functions in this module fall into `core_float_math`
 // #[unstable(feature = "core_float_math", issue = "137578")]
 #[cfg(not(test))]
-#[doc(test(attr(feature(cfg_target_has_reliable_f16_f128), expect(internal_features))))]
+#[doc(test(attr(
+    feature(cfg_target_has_reliable_f16_f128),
+    expect(internal_features),
+    allow(unused_features)
+)))]
 impl f128 {
     /// Returns the largest integer less than or equal to `self`.
     ///

library/core/src/num/f16.rs

@@ -142,7 +142,10 @@ pub mod consts {
     pub const LN_10: f16 = 2.30258509299404568401799145468436421_f16;
 }
 
-#[doc(test(attr(feature(cfg_target_has_reliable_f16_f128), allow(internal_features))))]
+#[doc(test(attr(
+    feature(cfg_target_has_reliable_f16_f128),
+    allow(internal_features, unused_features)
+)))]
 impl f16 {
     /// The radix or base of the internal representation of `f16`.
     #[unstable(feature = "f16", issue = "116909")]

library/core/src/num/f32.rs

@@ -1821,6 +1821,7 @@ pub const fn fract(x: f32) -> f32 {
     /// # Examples
     ///
     /// ```
+    /// # #![allow(unused_features)]
     /// #![feature(core_float_math)]
     ///
     /// # // FIXME(#140515): mingw has an incorrect fma

library/core/src/num/f64.rs

@@ -1819,6 +1819,7 @@ pub const fn fract(x: f64) -> f64 {
     /// # Examples
     ///
     /// ```
+    /// # #![allow(unused_features)]
     /// #![feature(core_float_math)]
     ///
     /// # // FIXME(#140515): mingw has an incorrect fma

library/core/src/num/uint_macros.rs

@@ -3072,7 +3072,6 @@ pub const fn widening_mul(self, rhs: Self) -> (Self, Self) {
         /// implementing it for wider-than-native types.
         ///
         /// ```
-        /// #![feature(const_unsigned_bigint_helpers)]
         /// fn scalar_mul_eq(little_endian_digits: &mut Vec<u16>, multiplicand: u16) {
         ///     let mut carry = 0;
         ///     for d in little_endian_digits.iter_mut() {
@@ -3097,6 +3096,7 @@ pub const fn widening_mul(self, rhs: Self) -> (Self, Self) {
         /// except that it gives the value of the overflow instead of just whether one happened:
         ///
         /// ```
+        /// # #![allow(unused_features)]
         /// #![feature(const_unsigned_bigint_helpers)]
         /// let r = u8::carrying_mul(7, 13, 0);
         /// assert_eq!((r.0, r.1 != 0), u8::overflowing_mul(7, 13));
@@ -3109,6 +3109,7 @@ pub const fn widening_mul(self, rhs: Self) -> (Self, Self) {
         /// [`wrapping_add`](Self::wrapping_add) methods:
         ///
         /// ```
+        /// # #![allow(unused_features)]
         /// #![feature(const_unsigned_bigint_helpers)]
         /// assert_eq!(
         ///     789_u16.carrying_mul(456, 123).0,

library/core/src/ptr/alignment.rs

@@ -112,7 +112,6 @@ pub const fn of_val<T: MetaSized>(val: &T) -> Self {
     ///
     /// ```
     /// #![feature(ptr_alignment_type)]
-    /// #![feature(layout_for_ptr)]
     /// use std::ptr::Alignment;
     ///
     /// assert_eq!(unsafe { Alignment::of_val_raw(&5i32) }.as_usize(), 4);

library/core/src/ptr/mut_ptr.rs

@@ -1800,7 +1800,6 @@ pub const fn is_empty(self) -> bool {
     ///
     /// ```
     /// #![feature(raw_slice_split)]
-    /// #![feature(slice_ptr_get)]
     ///
     /// let mut v = [1, 0, 3, 0, 5, 6];
     /// let ptr = &mut v as *mut [_];

library/core/src/time.rs

@@ -690,7 +690,6 @@ pub const fn checked_add(self, rhs: Duration) -> Option<Duration> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(duration_constants)]
     /// use std::time::Duration;
     ///
     /// assert_eq!(Duration::new(0, 0).saturating_add(Duration::new(0, 1)), Duration::new(0, 1));
@@ -801,7 +800,6 @@ pub const fn checked_mul(self, rhs: u32) -> Option<Duration> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(duration_constants)]
     /// use std::time::Duration;
     ///
     /// assert_eq!(Duration::new(0, 500_000_001).saturating_mul(2), Duration::new(1, 2));

library/coretests/tests/lib.rs

@@ -13,7 +13,6 @@
 #![feature(cfg_target_has_reliable_f16_f128)]
 #![feature(char_internals)]
 #![feature(char_max_len)]
-#![feature(clamp_magnitude)]
 #![feature(clone_to_uninit)]
 #![feature(const_array)]
 #![feature(const_bool)]
@@ -35,7 +34,6 @@
 #![feature(const_trait_impl)]
 #![feature(const_unsigned_bigint_helpers)]
 #![feature(control_flow_ok)]
-#![feature(core_float_math)]
 #![feature(core_intrinsics)]
 #![feature(core_intrinsics_fallbacks)]
 #![feature(core_io_borrowed_buf)]
@@ -47,7 +45,6 @@
 #![feature(drop_guard)]
 #![feature(duration_constants)]
 #![feature(duration_constructors)]
-#![feature(error_generic_member_access)]
 #![feature(exact_div)]
 #![feature(exact_size_is_empty)]
 #![feature(extend_one)]
@@ -55,7 +52,6 @@
 #![feature(f16)]
 #![feature(f128)]
 #![feature(float_algebraic)]
-#![feature(float_gamma)]
 #![feature(float_minimum_maximum)]
 #![feature(flt2dec)]
 #![feature(fmt_internals)]
@@ -94,7 +90,6 @@
 #![feature(nonzero_from_str_radix)]
 #![feature(numfmt)]
 #![feature(one_sided_range)]
-#![feature(option_reduce)]
 #![feature(pattern)]
 #![feature(pointer_is_aligned_to)]
 #![feature(portable_simd)]
@@ -114,7 +109,6 @@
 #![feature(step_trait)]
 #![feature(str_internals)]
 #![feature(strict_provenance_lints)]
-#![feature(test)]
 #![feature(trusted_len)]
 #![feature(trusted_random_access)]
 #![feature(try_blocks)]

library/std/src/num/f128.rs

@@ -16,6 +16,7 @@
 use crate::sys::cmath;
 
 #[cfg(not(test))]
+#[doc(test(attr(allow(unused_features))))]
 impl f128 {
     /// Raises a number to a floating point power.
     ///

library/std/src/num/f16.rs

@@ -916,7 +916,6 @@ pub fn atanh(self) -> f16 {
     ///
     /// ```
     /// #![feature(f16)]
-    /// #![feature(float_gamma)]
     /// # #[cfg(not(miri))]
     /// # #[cfg(target_has_reliable_f16_math)] {
     ///
@@ -952,7 +951,6 @@ pub fn gamma(self) -> f16 {
     ///
     /// ```
     /// #![feature(f16)]
-    /// #![feature(float_gamma)]
     /// # #[cfg(not(miri))]
     /// # #[cfg(target_has_reliable_f16_math)] {
     ///
@@ -988,7 +986,6 @@ pub fn ln_gamma(self) -> (f16, i32) {
     ///
     /// ```
     /// #![feature(f16)]
-    /// #![feature(float_erf)]
     /// # #[cfg(not(miri))]
     /// # #[cfg(target_has_reliable_f16_math)] {
     /// /// The error function relates what percent of a normal distribution lies
@@ -1028,7 +1025,6 @@ pub fn erf(self) -> f16 {
     ///
     /// ```
     /// #![feature(f16)]
-    /// #![feature(float_erf)]
     /// # #[cfg(not(miri))]
     /// # #[cfg(target_has_reliable_f16_math)] {
     /// let x: f16 = 0.123;

library/std/tests/floats/lib.rs

@@ -1,4 +1,4 @@
-#![feature(f16, f128, float_gamma, float_minimum_maximum, cfg_target_has_reliable_f16_f128)]
+#![feature(f16, f128, float_gamma, cfg_target_has_reliable_f16_f128)]
 #![expect(internal_features)] // for reliable_f16_f128
 
 use std::fmt;

library/std/tests/volatile-fat-ptr.rs

@@ -1,5 +1,4 @@
 #![allow(stable_features)]
-#![feature(volatile)]
 
 use std::ptr::{read_volatile, write_volatile};
 

library/std_detect/tests/cpu-detection.rs

@@ -1,4 +1,4 @@
-#![allow(internal_features)]
+#![allow(internal_features, unused_features)]
 #![feature(stdarch_internal)]
 #![cfg_attr(target_arch = "arm", feature(stdarch_arm_feature_detection))]
 #![cfg_attr(

library/std_detect/tests/macro_trailing_commas.rs

@@ -1,4 +1,4 @@
-#![allow(internal_features)]
+#![allow(internal_features, unused_features)]
 #![cfg_attr(
     any(
         target_arch = "arm",