diff --git a/util/crc32c.cc b/util/crc32c.cc
index 10b67e418..80094239c 100644
--- a/util/crc32c.cc
+++ b/util/crc32c.cc
@@ -41,7 +41,7 @@
 
 #endif
 
-#if defined(__linux__) && defined(HAVE_ARM64_CRC)
+#if defined(HAVE_ARM64_CRC)
 bool pmull_runtime_flag = false;
 #endif
 
@@ -478,7 +478,7 @@ static bool isAltiVec() {
 }
 #endif
 
-#if defined(__linux__) && defined(HAVE_ARM64_CRC)
+#if defined(HAVE_ARM64_CRC)
 uint32_t ExtendARMImpl(uint32_t crc, const char *buf, size_t size) {
   return crc32c_arm64(crc, (const unsigned char *)buf, size);
 }
@@ -498,7 +498,7 @@ std::string IsFastCrc32Supported() {
   has_fast_crc = false;
   arch = "PPC";
 #endif
-#elif defined(__linux__) && defined(HAVE_ARM64_CRC)
+#elif defined(HAVE_ARM64_CRC)
   if (crc32c_runtime_check()) {
     has_fast_crc = true;
     arch = "Arm64";
@@ -1231,7 +1231,7 @@ uint32_t crc32c_3way(uint32_t crc, const char* buf, size_t len) {
 static inline Function Choose_Extend() {
 #ifdef HAVE_POWER8
   return isAltiVec() ? ExtendPPCImpl : ExtendImpl<Slow_CRC32>;
-#elif defined(__linux__) && defined(HAVE_ARM64_CRC)
+#elif defined(HAVE_ARM64_CRC)
   if(crc32c_runtime_check()) {
     pmull_runtime_flag = crc32c_pmull_runtime_check();
     return ExtendARMImpl;
diff --git a/util/crc32c_arm64.cc b/util/crc32c_arm64.cc
index 566810f4b..80dbf0528 100644
--- a/util/crc32c_arm64.cc
+++ b/util/crc32c_arm64.cc
@@ -5,9 +5,11 @@
 
 #include "util/crc32c_arm64.h"
 
-#if defined(__linux__) && defined(HAVE_ARM64_CRC)
+#if defined(HAVE_ARM64_CRC)
 
+#if defined(__linux__)
 #include <asm/hwcap.h>
+#endif
 #ifdef ROCKSDB_AUXV_GETAUXVAL_PRESENT
 #include <sys/auxv.h>
 #endif
@@ -65,8 +67,8 @@ __attribute__((__no_sanitize__("alignment")))
 __attribute__((__no_sanitize_undefined__))
 #endif
 #endif
-uint32_t crc32c_arm64(uint32_t crc, unsigned char const *data,
-                             unsigned len) {
+uint32_t
+crc32c_arm64(uint32_t crc, unsigned char const *data, size_t len) {
   const uint8_t *buf8;
   const uint64_t *buf64 = (uint64_t *)data;
   int length = (int)len;
diff --git a/util/crc32c_arm64.h b/util/crc32c_arm64.h
index a12354683..b16b1f3e0 100644
--- a/util/crc32c_arm64.h
+++ b/util/crc32c_arm64.h
@@ -7,6 +7,7 @@
 #define UTIL_CRC32C_ARM64_H
 
 #include <cinttypes>
+#include <cstddef>
 
 #if defined(__aarch64__) || defined(__AARCH64__)
 
@@ -33,7 +34,8 @@
   PREF4X64L1(buffer, (PREF_OFFSET), 8) \
   PREF4X64L1(buffer, (PREF_OFFSET), 12)
 
-extern uint32_t crc32c_arm64(uint32_t crc, unsigned char const *data, unsigned len);
+extern uint32_t crc32c_arm64(uint32_t crc, unsigned char const *data,
+                             size_t len);
 extern uint32_t crc32c_runtime_check(void);
 extern bool crc32c_pmull_runtime_check(void);