From 878bcfd0a1e02a172c51654a718eb4f504b11e2b Mon Sep 17 00:00:00 2001
From: Artyom Pavlov <newpavlov@gmail.com>
Date: Fri, 1 Mar 2024 15:39:30 +0300
Subject: [PATCH] Fix Nightly warnings (#1055)

---
 blobby/src/lib.rs               |  1 -
 dbl/src/lib.rs                  |  2 --
 zeroize/src/lib.rs              | 57 ++++++++++++++-------------------
 zeroize/tests/zeroize_derive.rs |  1 +
 4 files changed, 25 insertions(+), 36 deletions(-)

diff --git a/blobby/src/lib.rs b/blobby/src/lib.rs
index b7d1737b..665b8b2d 100644
--- a/blobby/src/lib.rs
+++ b/blobby/src/lib.rs
@@ -51,7 +51,6 @@
 extern crate alloc;
 
 use alloc::{boxed::Box, collections::BTreeMap, vec, vec::Vec};
-use core::iter::Iterator;
 
 /// Iterator over binary blobs
 pub struct BlobIterator<'a> {
diff --git a/dbl/src/lib.rs b/dbl/src/lib.rs
index 7cd04e8b..00b49e19 100644
--- a/dbl/src/lib.rs
+++ b/dbl/src/lib.rs
@@ -9,8 +9,6 @@
 use hybrid_array::typenum::{U16, U32, U8};
 use hybrid_array::Array;
 
-use core::convert::TryInto;
-
 const C64: u64 = 0b1_1011;
 const C128: u64 = 0b1000_0111;
 const C256: u64 = 0b100_0010_0101;
diff --git a/zeroize/src/lib.rs b/zeroize/src/lib.rs
index 9326d075..6764015e 100644
--- a/zeroize/src/lib.rs
+++ b/zeroize/src/lib.rs
@@ -41,15 +41,13 @@
 //! ```
 //! use zeroize::Zeroize;
 //!
-//! fn main() {
-//!     // Protip: don't embed secrets in your source code.
-//!     // This is just an example.
-//!     let mut secret = b"Air shield password: 1,2,3,4,5".to_vec();
-//!     // [ ... ] open the air shield here
-//!
-//!     // Now that we're done using the secret, zero it out.
-//!     secret.zeroize();
-//! }
+//! // Protip: don't embed secrets in your source code.
+//! // This is just an example.
+//! let mut secret = b"Air shield password: 1,2,3,4,5".to_vec();
+//! // [ ... ] open the air shield here
+//!
+//! // Now that we're done using the secret, zero it out.
+//! secret.zeroize();
 //! ```
 //!
 //! The [`Zeroize`] trait is impl'd on all of Rust's core scalar types including
@@ -68,6 +66,7 @@
 //! memory is zeroed by converting it to a `Vec<u8>` and back into a `CString`.
 //! (NOTE: see "Stack/Heap Zeroing Notes" for important `Vec`/`String`/`CString` details)
 //!
+//! [`CString`]: https://doc.rust-lang.org/std/ffi/struct.CString.html
 //!
 //! The [`DefaultIsZeroes`] marker trait can be impl'd on types which also
 //! impl [`Default`], which implements [`Zeroize`] by overwriting a value with
@@ -143,7 +142,7 @@
 //! ```
 //! use zeroize::Zeroizing;
 //!
-//! fn main() {
+//! fn use_secret() {
 //!     let mut secret = Zeroizing::new([0u8; 5]);
 //!
 //!     // Set the air shield password
@@ -153,6 +152,8 @@
 //!
 //!     // The contents of `secret` will be automatically zeroized on drop
 //! }
+//!
+//! # use_secret()
 //! ```
 //!
 //! ## What guarantees does this crate provide?
@@ -800,31 +801,21 @@ unsafe fn volatile_set<T: Copy + Sized>(dst: *mut T, src: T, count: usize) {
 /// type that already implements `ZeroizeOnDrop`.
 ///
 /// # Safety
-/// - The type must not contain references to outside data or dynamically sized data, such as Vec<X>
-///   or String<X>.
-/// - This function can invalidate the type if it is used after this function is called on it. It is
-///   advisable to call this function in `impl Drop`.
-/// - The bit pattern of all zeroes must be valid for the data being zeroized. This may not be true for
-///   enums and pointers.
+/// - The type must not contain references to outside data or dynamically sized data, such as
+///   `Vec<T>` or `String`.
+/// - Values stored in the type must not have `Drop` impls.
+/// - This function can invalidate the type if it is used after this function is called on it.
+///   It is advisable to call this function only in `impl Drop`.
+/// - The bit pattern of all zeroes must be valid for the data being zeroized. This may not be
+///   true for enums and pointers.
 ///
 /// # Incompatible data types
-/// Some data types that cannot be safely zeroized using `zeroize_flat_type` include, but are not
-/// limited to:
-/// - pointers such as
-///   - *const u8
-///   - *mut u8
-/// - references such as
-///   - &T
-///   - &mut T
-/// - smart pointers and collections
-///   - Arc<T>
-///   - Box<T>
-///   - Vec<T>
-///   - HashMap<T1, T2>
-///   - String
-///
-/// Some data types that may be invalid after calling `zeroize_flat_type`:
-/// - enums
+/// Some data types that cannot be safely zeroized using `zeroize_flat_type` include,
+/// but are not limited to:
+/// - References: `&T` and `&mut T`
+/// - Non-nullable types: `NonNull<T>`, `NonZeroU32`, etc.
+/// - Enums with explicit non-zero tags.
+/// - Smart pointers and collections: `Arc<T>`, `Box<T>`, `Vec<T>`, `HashMap<K, V>`, `String`, etc.
 ///
 /// # Examples
 /// Safe usage for a struct containing strictly flat data:
diff --git a/zeroize/tests/zeroize_derive.rs b/zeroize/tests/zeroize_derive.rs
index c561ba61..e7939bf0 100644
--- a/zeroize/tests/zeroize_derive.rs
+++ b/zeroize/tests/zeroize_derive.rs
@@ -345,6 +345,7 @@ fn derive_zeroize_with_marker() {
         field: Option<A>,
     }
 
+    #[allow(dead_code)]
     trait Secret: ZeroizeOnDrop + Zeroize {}
 
     impl<A: Marker> Secret for Test<A> {}