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    //! Just like [`Cell`] but with [volatile] read / write operations
    //!
    //! [`Cell`]: https://doc.rust-lang.org/std/cell/struct.Cell.html
    //! [volatile]: https://doc.rust-lang.org/std/ptr/fn.read_volatile.html

    #![deny(missing_docs)]
    #![deny(warnings)]
    #![cfg_attr(feature = "const-fn", feature(const_fn))]
    #![no_std]

    use core::cell::UnsafeCell;
    use core::ptr;

    /// Just like [`Cell`] but with [volatile] read / write operations
    ///
    /// [`Cell`]: https://doc.rust-lang.org/std/cell/struct.Cell.html
    /// [volatile]: https://doc.rust-lang.org/std/ptr/fn.read_volatile.html
    pub struct VolatileCell<T> {
        value: UnsafeCell<T>,
    }

    impl<T> VolatileCell<T> {
        /// Creates a new `VolatileCell` containing the given value
        #[cfg(feature = "const-fn")]
        pub const fn new(value: T) -> Self {
            VolatileCell { value: UnsafeCell::new(value) }
        }

        /// Creates a new `VolatileCell` containing the given value
        ///
        /// NOTE A `const fn` variant is available under the "const-fn" Cargo
        /// feature
        #[cfg(not(feature = "const-fn"))]
        pub fn new(value: T) -> Self {
            VolatileCell { value: UnsafeCell::new(value) }
        }

        /// Returns a copy of the contained value
        #[inline(always)]
        pub fn get(&self) -> T
            where T: Copy
        {
            unsafe { ptr::read_volatile(self.value.get()) }
        }

        /// Sets the contained value
        #[inline(always)]
        pub fn set(&self, value: T)
            where T: Copy
        {
            unsafe { ptr::write_volatile(self.value.get(), value) }
        }
    }

    // NOTE implicit because of `UnsafeCell`
    // unsafe impl<T> !Sync for VolatileCell<T> {}

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