From eb64585d3c7152ebf9e3d1bf07b47de8ff09718e Mon Sep 17 00:00:00 2001
From: missing <piecenotfound@gmail.com>
Date: Sun, 25 Dec 2022 22:43:23 -0600
Subject: [PATCH] clarify provenance issue in `new_owned`

---
 src/lib.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/lib.rs b/src/lib.rs
index 72b2037..7761f6a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -94,6 +94,9 @@ impl Stringish {
     /// Alternatively, use the [`Ish::ish`] method.
     #[must_use]
     pub fn new_owned(s: String) -> Self {
+        // converting to a `Vec` is necessary since `s.as_mut_ptr()` would call `str::as_mut_ptr`
+        // through deref coercion, which would only give us a pointer with provenance to the
+        // initialized part of the `String`, which is not enough to deallocate.
         let mut v = ManuallyDrop::new(s.into_bytes());
         Self {
             // SAFETY: `v.as_mut_ptr()` is never null