+#include <stdio.h>
+
+static inline lispobj
+swap_lispobjs(volatile lispobj *dest, lispobj value)
+{
+ lispobj old_value;
+#if defined(LISP_FEATURE_DARWIN)
+ asm ("lock/xchg %0,(%1)"
+ : "=r" (old_value)
+ : "r" (dest), "0" (value)
+ : "memory");
+#else
+ asm ("lock xchg %0,(%1)"
+ : "=r" (old_value)
+ : "r" (dest), "0" (value)
+ : "memory");
+#endif
+ return old_value;
+}
+
+extern void fast_bzero_detect(void *, size_t);
+extern void (*fast_bzero_pointer)(void *, size_t);
+