From 773997b9789c8499b234f15ab56a7eac415fcc9f Mon Sep 17 00:00:00 2001
From: itsjunetime <junewelker@gmail.com>
Date: Wed, 16 Oct 2024 14:19:34 -0600
Subject: [PATCH] Switch back to casting metadata to *const u8 for c_char = i8
 platforms

---
 arrow-schema/src/ffi.rs | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arrow-schema/src/ffi.rs b/arrow-schema/src/ffi.rs
index 80b23e593421..70650d769cf6 100644
--- a/arrow-schema/src/ffi.rs
+++ b/arrow-schema/src/ffi.rs
@@ -336,7 +336,12 @@ impl FFI_ArrowSchema {
             Ok(HashMap::new())
         } else {
             let mut pos = 0;
-            let buffer: *const u8 = self.metadata;
+
+            // On some platforms, c_char = u8, and on some, c_char = i8. Where c_char = u8, clippy
+            // wants to complain that we're casting to the same type, but if we remove the cast,
+            // this will fail to compile on the other platforms. So we must allow it.
+            #[allow(clippy::unnecessary_cast)]
+            let buffer: *const u8 = self.metadata as *const u8;
 
             fn next_four_bytes(buffer: *const u8, pos: &mut isize) -> [u8; 4] {
                 let out = unsafe {