From: Nathan Moinvaziri <nathan@nathanm.com>
Date: Thu, 4 Jan 2024 22:32:06 +0000 (-0800)
Subject: Prefer HAVE_ALIGNED_ALLOC when available in zng_alloc
X-Git-Tag: 2.2.0~83
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=42db8b86a842e92e2dd9695860b03bcbdf3fe1c0;p=thirdparty%2Fzlib-ng.git

Prefer HAVE_ALIGNED_ALLOC when available in zng_alloc

Added some more helpful comments for people who come across this code.
---

diff --git a/zutil_p.h b/zutil_p.h
index caec91d5..bc6f9698 100644
--- a/zutil_p.h
+++ b/zutil_p.h
@@ -16,15 +16,17 @@
 
 /* Function to allocate 16 or 64-byte aligned memory */
 static inline void *zng_alloc(size_t size) {
-#ifdef HAVE_POSIX_MEMALIGN
+#ifdef HAVE_ALIGNED_ALLOC
+    return (void *)aligned_alloc(64, size);  /* Defined in C11 */
+#elif defined(HAVE_POSIX_MEMALIGN)
     void *ptr;
     return posix_memalign(&ptr, 64, size) ? NULL : ptr;
 #elif defined(_WIN32)
     return (void *)_aligned_malloc(size, 64);
 #elif defined(__APPLE__)
-    return (void *)malloc(size);     /* MacOS always aligns to 16 bytes */
-#elif defined(HAVE_ALIGNED_ALLOC)
-    return (void *)aligned_alloc(64, size);
+    /* Fallback for when posix_memalign and aligned_alloc are not available.
+     * On macOS, it always aligns to 16 bytes. */
+    return (void *)malloc(size);
 #else
     return (void *)memalign(64, size);
 #endif