From 95d6e0b2830c8e6bfd861042f6df6343891d5843 Mon Sep 17 00:00:00 2001
From: Chris Eibl <138194463+chris-eibl@users.noreply.github.com>
Date: Mon, 25 Aug 2025 22:59:52 +0200
Subject: [PATCH] GH-131033: Enable the optimizing macros UNLIKELY and LIKELY
 for Clang (GH-131019)

This includes clang-cl on Windows, which does not define the GCC version that was previously being checked.
---
 Objects/obmalloc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Objects/obmalloc.c b/Objects/obmalloc.c
index deb7fd957e57..2b95ebbf8e5a 100644
--- a/Objects/obmalloc.c
+++ b/Objects/obmalloc.c
@@ -1523,9 +1523,9 @@ PyObject_Free(void *ptr)
 }
 
 
-/* If we're using GCC, use __builtin_expect() to reduce overhead of
+/* Use __builtin_expect() where available to reduce overhead of
    the valgrind checks */
-#if defined(__GNUC__) && (__GNUC__ > 2) && defined(__OPTIMIZE__)
+#if (defined(__clang__) || (defined(__GNUC__) && (__GNUC__ > 2))) && defined(__OPTIMIZE__)
 #  define UNLIKELY(value) __builtin_expect((value), 0)
 #  define LIKELY(value) __builtin_expect((value), 1)
 #else
-- 
2.47.3