From 0e30223564e272b698250e41255e188e0a7d1430 Mon Sep 17 00:00:00 2001
From: Andrew Lamb <andrew@nerdnetworks.org>
Date: Fri, 9 Jan 2026 16:17:55 -0500
Subject: [PATCH 1/2] perf: Avoid allocation in
 PrimitiveArray::reinterpret_cast

---
 arrow-array/src/array/primitive_array.rs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arrow-array/src/array/primitive_array.rs b/arrow-array/src/array/primitive_array.rs
index 457c2428145e..cde490a3ab18 100644
--- a/arrow-array/src/array/primitive_array.rs
+++ b/arrow-array/src/array/primitive_array.rs
@@ -859,11 +859,9 @@ impl<T: ArrowPrimitiveType> PrimitiveArray<T> {
     where
         K: ArrowPrimitiveType<Native = T::Native>,
     {
-        let d = self.to_data().into_builder().data_type(K::DATA_TYPE);
-
         // SAFETY:
         // Native type is the same
-        PrimitiveArray::from(unsafe { d.build_unchecked() })
+        PrimitiveArray::new(self.values.clone(), self.nulls.clone())
     }
 
     /// Applies a unary infallible function to a primitive array, producing a

From 0dcbcd67b54c0142e8a2f85037a0ede65cd6f293 Mon Sep 17 00:00:00 2001
From: Andrew Lamb <andrew@nerdnetworks.org>
Date: Fri, 9 Jan 2026 16:24:20 -0500
Subject: [PATCH 2/2] stale commens

---
 arrow-array/src/array/primitive_array.rs | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arrow-array/src/array/primitive_array.rs b/arrow-array/src/array/primitive_array.rs
index cde490a3ab18..87de5f61605f 100644
--- a/arrow-array/src/array/primitive_array.rs
+++ b/arrow-array/src/array/primitive_array.rs
@@ -859,8 +859,6 @@ impl<T: ArrowPrimitiveType> PrimitiveArray<T> {
     where
         K: ArrowPrimitiveType<Native = T::Native>,
     {
-        // SAFETY:
-        // Native type is the same
         PrimitiveArray::new(self.values.clone(), self.nulls.clone())
     }