Adding a zeroize function for flat types

zeroize/src/lib.rs

@@ -795,6 +795,20 @@ unsafe fn volatile_set<T: Copy + Sized>(dst: *mut T, src: T, count: usize) {
     }
 }
 
+/// Zeroizes a flat type/struct. Only zeroizes the values that it owns, and it does not work on
+/// dynamically sized values or trait objects.
+#[inline(always)]
+pub fn zeroize_flat_type<T: Sized>(data: &mut T) {
+    let size = mem::size_of::<T>();
+    let data_ptr = (data as *mut T).cast::<u8>();
+    // Safety:
+    //
+    // This is safe because `mem::size_of<T>()` returns the exact size of the object in memory, and
+    // `data_ptr` points directly to the first byte of the data.
+    unsafe { volatile_set(data_ptr, 0, size) }
+    atomic_fence()
+}
+
 /// Internal module used as support for `AssertZeroizeOnDrop`.
 #[doc(hidden)]
 pub mod __internal {