From 53459ffa8c0b9060f111b4730d1fe58a110470d9 Mon Sep 17 00:00:00 2001
From: Vilim Lendvaj <vilim.lendvaj@sk.t-com.hr>
Date: Mon, 5 May 2025 21:38:25 +0200
Subject: [PATCH] Simplify `Vec::as_non_null` implementation and make it
 `const`

---
 library/alloc/src/raw_vec/mod.rs | 2 +-
 library/alloc/src/vec/mod.rs     | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/library/alloc/src/raw_vec/mod.rs b/library/alloc/src/raw_vec/mod.rs
index a989e5b55b3d1..3e006a2d1bdf1 100644
--- a/library/alloc/src/raw_vec/mod.rs
+++ b/library/alloc/src/raw_vec/mod.rs
@@ -287,7 +287,7 @@ impl<T, A: Allocator> RawVec<T, A> {
     }
 
     #[inline]
-    pub(crate) fn non_null(&self) -> NonNull<T> {
+    pub(crate) const fn non_null(&self) -> NonNull<T> {
         self.inner.non_null()
     }
 
diff --git a/library/alloc/src/vec/mod.rs b/library/alloc/src/vec/mod.rs
index a97912304c894..59879f23d7850 100644
--- a/library/alloc/src/vec/mod.rs
+++ b/library/alloc/src/vec/mod.rs
@@ -1816,10 +1816,10 @@ impl<T, A: Allocator> Vec<T, A> {
     /// [`as_ptr`]: Vec::as_ptr
     /// [`as_non_null`]: Vec::as_non_null
     #[unstable(feature = "box_vec_non_null", reason = "new API", issue = "130364")]
+    #[rustc_const_unstable(feature = "box_vec_non_null", reason = "new API", issue = "130364")]
     #[inline]
-    pub fn as_non_null(&mut self) -> NonNull<T> {
-        // SAFETY: A `Vec` always has a non-null pointer.
-        unsafe { NonNull::new_unchecked(self.as_mut_ptr()) }
+    pub const fn as_non_null(&mut self) -> NonNull<T> {
+        self.buf.non_null()
     }
 
     /// Returns a reference to the underlying allocator.