diff --git a/src/google/protobuf/stubs/atomicops_internals_atomicword_compat.h b/src/google/protobuf/stubs/atomicops_internals_atomicword_compat.h
index 8d9a726c2..e9d86797b 100644
--- a/src/google/protobuf/stubs/atomicops_internals_atomicword_compat.h
+++ b/src/google/protobuf/stubs/atomicops_internals_atomicword_compat.h
@@ -44,7 +44,7 @@
 // On LP64 platforms, AtomicWord and Atomic64 are both always long,
 // so this problem doesn't occur.
 
-#if !defined(GOOGLE_PROTOBUF_HOST_ARCH_64_BIT)
+#if !defined(GOOGLE_PROTOBUF_ARCH_64_BIT)
 
 namespace google {
 namespace protobuf {
@@ -117,6 +117,6 @@ inline AtomicWord Release_Load(volatile const AtomicWord* ptr) {
 }   // namespace protobuf
 }   // namespace google
 
-#endif  // !defined(GOOGLE_PROTOBUF_HOST_ARCH_64_BIT)
+#endif  // !defined(GOOGLE_PROTOBUF_ARCH_64_BIT)
 
 #endif  // GOOGLE_PROTOBUF_ATOMICOPS_INTERNALS_ATOMICWORD_COMPAT_H_
diff --git a/src/google/protobuf/stubs/atomicops_internals_macosx.h b/src/google/protobuf/stubs/atomicops_internals_macosx.h
index 9af6d636d..f9b7581ad 100644
--- a/src/google/protobuf/stubs/atomicops_internals_macosx.h
+++ b/src/google/protobuf/stubs/atomicops_internals_macosx.h
@@ -136,7 +136,7 @@ inline Atomic64 NoBarrier_CompareAndSwap(volatile Atomic64* ptr,
   Atomic64 prev_value;
   do {
     if (OSAtomicCompareAndSwap64(old_value, new_value,
-                                 const_cast<Atomic64*>(ptr))) {
+                                 reinterpret_cast<volatile int64_t*>(ptr))) {
       return old_value;
     }
     prev_value = *ptr;
@@ -150,18 +150,19 @@ inline Atomic64 NoBarrier_AtomicExchange(volatile Atomic64* ptr,
   do {
     old_value = *ptr;
   } while (!OSAtomicCompareAndSwap64(old_value, new_value,
-                                     const_cast<Atomic64*>(ptr)));
+                                     reinterpret_cast<volatile int64_t*>(ptr)));
   return old_value;
 }
 
 inline Atomic64 NoBarrier_AtomicIncrement(volatile Atomic64* ptr,
                                           Atomic64 increment) {
-  return OSAtomicAdd64(increment, const_cast<Atomic64*>(ptr));
+  return OSAtomicAdd64(increment, reinterpret_cast<volatile int64_t*>(ptr));
 }
 
 inline Atomic64 Barrier_AtomicIncrement(volatile Atomic64* ptr,
                                         Atomic64 increment) {
-  return OSAtomicAdd64Barrier(increment, const_cast<Atomic64*>(ptr));
+  return OSAtomicAdd64Barrier(increment,
+                              reinterpret_cast<volatile int64_t*>(ptr));
 }
 
 inline Atomic64 Acquire_CompareAndSwap(volatile Atomic64* ptr,
@@ -169,8 +170,8 @@ inline Atomic64 Acquire_CompareAndSwap(volatile Atomic64* ptr,
                                        Atomic64 new_value) {
   Atomic64 prev_value;
   do {
-    if (OSAtomicCompareAndSwap64Barrier(old_value, new_value,
-                                        const_cast<Atomic64*>(ptr))) {
+    if (OSAtomicCompareAndSwap64Barrier(
+        old_value, new_value, reinterpret_cast<volatile int64_t*>(ptr))) {
       return old_value;
     }
     prev_value = *ptr;