Index: src/atomic.h
==================================================================
--- src/atomic.h
+++ src/atomic.h
@@ -497,17 +497,17 @@
 	return NO;
 #elif defined(OF_X86_ASM) || defined(OF_AMD64_ASM)
 	int r;
 
 	__asm__ (
+	    "xorl	%0, %0\n\t"
 	    "lock\n\t"
 	    "cmpxchg	%2, %3\n\t"
-	    "lahf\n\t"
-	    "andb	$64, %%ah\n\t"
-	    "shrb	$6, %%ah\n\t"
-	    "movzx	%%ah, %0\n\t"
-	    : "=a"(r)
+	    "jne	.1\n\t"
+	    "incl	%0\n"
+	    ".1:"
+	    : "=&r"(r)
 	    : "a"(o), "r"(n), "m"(*p)
 	);
 
 	return r;
 #elif defined(OF_HAVE_GCC_ATOMIC_OPS)
@@ -526,20 +526,20 @@
 		return YES;
 	}
 
 	return NO;
 #elif defined(OF_X86_ASM) || defined(OF_AMD64_ASM)
-	uint32_t r;
+	int r;
 
 	__asm__ (
+	    "xorl	%0, %0\n\t"
 	    "lock\n\t"
 	    "cmpxchg	%2, %3\n\t"
-	    "lahf\n\t"
-	    "andb	$64, %%ah\n\t"
-	    "shrb	$6, %%ah\n\t"
-	    "movzx	%%ah, %0\n\t"
-	    : "=a"(r)
+	    "jne	.1\n\t"
+	    "incl	%0\n"
+	    ".1:"
+	    : "=&r"(r)
 	    : "a"(o), "r"(n), "m"(*p)
 	);
 
 	return r;
 #elif defined(OF_HAVE_GCC_ATOMIC_OPS)
@@ -558,25 +558,25 @@
 		return YES;
 	}
 
 	return NO;
 #elif defined(OF_X86_ASM) || defined(OF_AMD64_ASM)
-	uint32_t r;
+	int r;
 
 	__asm__ (
+	    "xorl	%0, %0\n\t"
 	    "lock\n\t"
 	    "cmpxchg	%2, %3\n\t"
-	    "lahf\n\t"
-	    "andb	$64, %%ah\n\t"
-	    "shrb	$6, %%ah\n\t"
-	    "movzx	%%ah, %0\n\t"
-	    : "=a"(r)
-	    : "a"(o), "q"(n), "m"(*p)
+	    "jne	.1\n\t"
+	    "incl	%0\n"
+	    ".1:"
+	    : "=&r"(r)
+	    : "a"(o), "r"(n), "m"(*p)
 	);
 
 	return r;
 #elif defined(OF_HAVE_GCC_ATOMIC_OPS)
 	return __sync_bool_compare_and_swap(p, o, n);
 #elif defined(OF_HAVE_OSATOMIC)
 	return OSAtomicCompareAndSwapPtrBarrier(o, n, p);
 #endif
 }