#include <urcu/compiler.h>
+#ifndef __SIZEOF_LONG__
+#if defined(__x86_64__) || defined(__amd64__)
+#define __SIZEOF_LONG__ 8
+#else
+#define __SIZEOF_LONG__ 4
+#endif
+#endif
+
#ifndef BITS_PER_LONG
#define BITS_PER_LONG (__SIZEOF_LONG__ * 8)
#endif
#define uatomic_dec(addr) (_uatomic_dec((addr), sizeof(*(addr))))
+#if (BITS_PER_LONG == 64)
+#define URCU_CAS_AVAIL() 1
+#define compat_uatomic_cmpxchg(ptr, old, _new) uatomic_cmpxchg(ptr, old, _new)
+#else
+extern int __urcu_cas_avail;
+extern int __urcu_cas_init(void);
+#define URCU_CAS_AVAIL() \
+ ((likely(__urcu_cas_avail > 0)) ? \
+ (1) : \
+ ((unlikely(__urcu_cas_avail < 0) ? \
+ (__urcu_cas_init()) : \
+ (0))))
+
+extern unsigned long _compat_uatomic_cmpxchg(void *addr, unsigned long old,
+ unsigned long _new, int len);
+
+#define compat_uatomic_cmpxchg(addr, old, _new) \
+ ((__typeof__(*(addr))) _uatomic_cmpxchg((addr), (unsigned long)(old),\
+ (unsigned long)(_new), \
+ sizeof(*(addr))))
+#endif
+
#endif /* _URCU_ARCH_UATOMIC_X86_H */