refactor: remove #![feature(const_fn_fn_ptr_basics)]

The `const_fn_fn_ptr_basics` feature was stabilized by
<rust-lang/rust#93827>.

README.md

@@ -46,7 +46,6 @@ The R3 original kernel is provided as a separate package [`r3_kernel`][].
 ## Example
 
 ```rust
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(naked_functions)]

examples/basic/src/main.rs

@@ -1,4 +1,3 @@
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(const_mut_refs)]

examples/basic_gr_peach/src/main.rs

@@ -1,4 +1,3 @@
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(const_mut_refs)]

examples/basic_nucleo_f401re/src/main.rs

@@ -1,4 +1,3 @@
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(naked_functions)]

examples/basic_rp_pico/src/main.rs

@@ -1,4 +1,3 @@
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(naked_functions)]

examples/basic_wio_terminal/src/main.rs

@@ -1,4 +1,3 @@
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(naked_functions)]

examples/smp_rp_pico/src/main.rs

@@ -1,4 +1,3 @@
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(naked_functions)]

src/r3/src/lib.rs

@@ -1,7 +1,6 @@
 #![feature(arbitrary_enum_discriminant)]
 #![feature(type_changing_struct_update)]
 #![feature(const_precise_live_drops)]
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(type_alias_impl_trait)]
 #![feature(const_trait_impl)]
 #![feature(const_mut_refs)]

src/r3/src/tests.rs

@@ -8,8 +8,7 @@ pub(crate) macro doc_test(
     $( #[doc = $doc:expr] )*
 ) {concat!(
 ignore_if_port_std_does_not_support_target!($head), "\n ",
-"#   #![feature(const_fn_fn_ptr_basics)]
- #   #![feature(const_refs_to_cell)]
+"#   #![feature(const_refs_to_cell)]
  #   #![feature(const_trait_impl)]
  #   #![feature(const_mut_refs)]
  #   #![deny(unsafe_op_in_unsafe_fn)]

src/r3_core/src/bind.rs

@@ -692,7 +692,6 @@ impl<'pool, System, T> DivideBind<'pool, System, T> {
 /// # Examples
 ///
 /// ```rust
-/// #![feature(const_fn_fn_ptr_basics)]
 /// #![feature(const_trait_impl)]
 /// #![feature(const_mut_refs)]
 /// use r3_core::{bind::Bind, kernel::{Cfg, traits}, prelude::*};
@@ -821,7 +820,6 @@ impl<'pool, const LEN: usize, System, T> const UnzipBind for Bind<'pool, System,
 /// # Example
 ///
 /// ```rust
-/// #![feature(const_fn_fn_ptr_basics)]
 /// #![feature(const_trait_impl)]
 /// #![feature(const_mut_refs)]
 /// use r3_core::{

src/r3_core/src/kernel/timer.rs

@@ -272,7 +272,6 @@ define_object! {
 /// ## Periodic Timer
 ///
 /// ```rust
-/// # #![feature(const_fn_fn_ptr_basics)]
 /// # #![feature(const_trait_impl)]
 /// # #![feature(const_mut_refs)]
 /// use r3_core::{kernel::{Cfg, StaticTimer, traits}, time::Duration};
@@ -313,7 +312,6 @@ define_object! {
 /// ## One-Shot Timer
 ///
 /// ```rust
-/// # #![feature(const_fn_fn_ptr_basics)]
 /// # #![feature(const_trait_impl)]
 /// # #![feature(const_mut_refs)]
 /// use r3_core::{kernel::{Cfg, StaticTimer, traits, prelude::*}, time::Duration};

src/r3_core/src/lib.md

@@ -103,7 +103,6 @@ fn task_body() {
 Configuration functions are highly composable as they can make nested calls to other configuration functions. In some sense, this is a way to attribute a certain semantics to a group of kernel objects, encapsulate them, and expose a higher-level interface. For example, a [mutex object] similar to `std::sync::Mutex` can be created by combining [`kernel::Mutex`]`<System>` (a low-level mutex object) and a [`hunk::Hunk`]`<System, UnsafeCell<T>>` (a typed hunk), which in turn is built on top of [`kernel::Hunk`]`<System>` (a low-level untyped hunk).
 
 ```rust
-# #![feature(const_fn_fn_ptr_basics)]
 # #![feature(const_trait_impl)]
 # #![feature(const_mut_refs)]
 # use r3_core::kernel::{Cfg, traits};

src/r3_core/src/lib.rs

@@ -10,7 +10,6 @@
 #![feature(const_precise_live_drops)]
 #![feature(const_raw_ptr_comparison)]
 #![feature(generic_associated_types)]
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_slice_first_last)]
 #![feature(cfg_target_has_atomic)] // `#[cfg(target_has_atomic_load_store)]`
 #![feature(const_cell_into_inner)]

src/r3_kernel/src/lib.rs

@@ -3,7 +3,6 @@
 #![feature(maybe_uninit_uninit_array)]
 #![feature(const_precise_live_drops)]
 #![feature(const_raw_ptr_comparison)]
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(cfg_target_has_atomic)] // `#[cfg(target_has_atomic_load_store)]`
 #![feature(const_intrinsic_copy)]
 #![feature(exhaustive_patterns)] // `let Ok(()) = Ok::<(), !>(())`

src/r3_port_arm/src/lib.rs

@@ -1,4 +1,3 @@
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_ptr_offset_from)]
 #![feature(const_refs_to_cell)]
 #![feature(const_ptr_offset)]

src/r3_port_arm_m/src/lib.rs

@@ -1,4 +1,3 @@
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_ptr_offset_from)]
 #![feature(generic_const_exprs)]
 #![feature(const_refs_to_cell)]

src/r3_port_arm_m_test_driver/src/main.rs

@@ -1,4 +1,3 @@
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(naked_functions)]

src/r3_port_arm_test_driver/src/main.rs

@@ -3,7 +3,6 @@
 //! padding-bottom: 100%" href="http://derpibooru.org/2079083"
 //! title="Screwdriver"></a></div>
 #![doc = include_str!("./common.md")]
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(naked_functions)]

src/r3_port_riscv/src/lib.rs

@@ -1,4 +1,3 @@
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(generic_const_exprs)]
 #![feature(const_trait_impl)]
 #![feature(naked_functions)]

src/r3_port_riscv_test_driver/src/main.rs

@@ -1,4 +1,3 @@
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(const_ptr_offset)]

src/r3_port_std/src/lib.md

@@ -3,7 +3,6 @@ The port for running [`::r3_kernel`][] in a hosted environment
 # Usage
 
 ```rust
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(const_mut_refs)]

src/r3_port_std/tests/test_suite.rs

@@ -1,5 +1,4 @@
 //! Runs test cases defined in `r3_test_suite`.
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_refs_to_cell)]
 #![feature(const_trait_impl)]
 #![feature(const_mut_refs)]

src/r3_portkit/src/lib.rs

@@ -1,5 +1,4 @@
 //! R3 PortKit
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(generic_const_exprs)]
 #![feature(adt_const_params)]
 #![feature(naked_functions)]

src/r3_support_rp2040/src/lib.rs

@@ -3,7 +3,6 @@
 //!
 //! [R3]: ::r3
 //! [Raspberry Pi Pico]: https://pico.raspberrypi.org
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(exhaustive_patterns)]
 #![feature(const_trait_impl)]
 #![feature(const_mut_refs)]

src/r3_support_rza1/src/lib.rs

@@ -4,7 +4,6 @@
 //! [R3]: ::r3
 //! [RZ/A1H]: https://www.renesas.com/us/en/products/microcontrollers-microprocessors/rz/rza/rza1h.html
 //! [GR-PEACH]: https://www.renesas.com/us/en/products/gadget-renesas/boards/gr-peach.html
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(const_trait_impl)]
 #![feature(const_mut_refs)]
 #![cfg_attr(

src/r3_test_suite/src/lib.rs

@@ -1,5 +1,4 @@
 #![feature(const_fn_floating_point_arithmetic)]
-#![feature(const_fn_fn_ptr_basics)]
 #![feature(cfg_target_has_atomic)]
 #![feature(const_transmute_copy)]
 #![feature(const_refs_to_cell)]