Index: src/atomic.h
==================================================================
--- src/atomic.h
+++ src/atomic.h
@@ -69,11 +69,11 @@
 	    : "r"(i), "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicAdd32Barrier(i, p);
+	return OSAtomicAdd32(i, p);
 #else
 # error of_atomic_int_add not implemented!
 #endif
 }
 
@@ -105,11 +105,11 @@
 	    : "r"(i), "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicAdd32Barrier(i, p);
+	return OSAtomicAdd32(i, p);
 #else
 # error of_atomic_int32_add not implemented!
 #endif
 }
 
@@ -152,13 +152,13 @@
 	);
 
 	return (void*)i;
 #elif defined(OF_HAVE_OSATOMIC)
 # ifdef __LP64__
-	return (void*)OSAtomicAdd64Barrier(i, (int64_t*)p);
+	return (void*)OSAtomicAdd64(i, (int64_t*)p);
 # else
-	return (void*)OSAtomicAdd32Barrier(i, (int32_t*)p);
+	return (void*)OSAtomicAdd32(i, (int32_t*)p);
 # endif
 #else
 # error of_atomic_ptr_add not implemented!
 #endif
 }
@@ -206,11 +206,11 @@
 	    : "r"(i), "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicAdd32Barrier(-i, p);
+	return OSAtomicAdd32(-i, p);
 #else
 # error of_atomic_int_sub not implemented!
 #endif
 }
 
@@ -243,11 +243,11 @@
 	    : "r"(i), "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicAdd32Barrier(-i, p);
+	return OSAtomicAdd32(-i, p);
 #else
 # error of_atomic_int32_sub not implemented!
 #endif
 }
 
@@ -292,13 +292,13 @@
 	);
 
 	return (void*)i;
 #elif defined(OF_HAVE_OSATOMIC)
 # ifdef __LP64__
-	return (void*)OSAtomicAdd64Barrier(-i, (int64_t*)p);
+	return (void*)OSAtomicAdd64(-i, (int64_t*)p);
 # else
-	return (void*)OSAtomicAdd32Barrier(-i, (int32_t*)p);
+	return (void*)OSAtomicAdd32(-i, (int32_t*)p);
 # endif
 #else
 # error of_atomic_ptr_sub not implemented!
 #endif
 }
@@ -352,11 +352,11 @@
 	    : "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicIncrement32Barrier(p);
+	return OSAtomicIncrement32(p);
 #else
 # error of_atomic_int_inc not implemented!
 #endif
 }
 
@@ -394,11 +394,11 @@
 	    : "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicIncrement32Barrier(p);
+	return OSAtomicIncrement32(p);
 #else
 # error of_atomic_int32_inc not implemented!
 #endif
 }
 
@@ -451,11 +451,11 @@
 	    : "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicDecrement32Barrier(p);
+	return OSAtomicDecrement32(p);
 #else
 # error of_atomic_int_dec not implemented!
 #endif
 }
 
@@ -493,11 +493,11 @@
 	    : "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicDecrement32Barrier(p);
+	return OSAtomicDecrement32(p);
 #else
 # error of_atomic_int32_dec not implemented!
 #endif
 }
 
@@ -552,11 +552,11 @@
 	    : "r"(i), "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicOr32Barrier(i, p);
+	return OSAtomicOr32(i, p);
 #else
 # error of_atomic_int_or not implemented!
 #endif
 }
 
@@ -593,11 +593,11 @@
 	    : "r"(i), "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicOr32Barrier(i, p);
+	return OSAtomicOr32(i, p);
 #else
 # error of_atomic_int32_or not implemented!
 #endif
 }
 
@@ -652,11 +652,11 @@
 	    : "r"(i), "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicAnd32Barrier(i, p);
+	return OSAtomicAnd32(i, p);
 #else
 # error of_atomic_int_and not implemented!
 #endif
 }
 
@@ -693,11 +693,11 @@
 	    : "r"(i), "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicAnd32Barrier(i, p);
+	return OSAtomicAnd32(i, p);
 #else
 # error of_atomic_int32_and not implemented!
 #endif
 }
 
@@ -752,11 +752,11 @@
 	    : "r"(i), "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicXor32Barrier(i, p);
+	return OSAtomicXor32(i, p);
 #else
 # error of_atomic_int_xor not implemented!
 #endif
 }
 
@@ -793,11 +793,11 @@
 	    : "r"(i), "r"(p)
 	);
 
 	return i;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicXor32Barrier(i, p);
+	return OSAtomicXor32(i, p);
 #else
 # error of_atomic_int32_xor not implemented!
 #endif
 }
 
@@ -848,11 +848,11 @@
 	    : "cc"
 	);
 
 	return r;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicCompareAndSwapIntBarrier(o, n, p);
+	return OSAtomicCompareAndSwapInt(o, n, p);
 #else
 # error of_atomic_int_cmpswap not implemented!
 #endif
 }
 
@@ -903,11 +903,11 @@
 	    : "cc"
 	);
 
 	return r;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicCompareAndSwap32Barrier(o, n, p);
+	return OSAtomicCompareAndSwap32(o, n, p);
 #else
 # error of_atomic_int32_cmpswap not implemented!
 #endif
 }
 
@@ -959,11 +959,11 @@
 	    : "cc"
 	);
 
 	return r;
 #elif defined(OF_HAVE_OSATOMIC)
-	return OSAtomicCompareAndSwapPtrBarrier(o, n, p);
+	return OSAtomicCompareAndSwapPtr(o, n, p);
 #else
 # error of_atomic_ptr_cmpswap not implemented!
 #endif
 }
 

Index: src/threading.m
==================================================================
--- src/threading.m
+++ src/threading.m
@@ -30,10 +30,13 @@
 void
 of_once(of_once_t *control, void (*func)(void))
 {
 	if (of_atomic_int_cmpswap(control, 0, 1)) {
 		func();
+
+		of_memory_barrier();
+
 		of_atomic_int_inc(control);
 	} else
 		while (*control == 1)
 			of_thread_yield();
 }