This corrects a linker error on OpenBSD, where the function is called letoh64. See also http://git.kernel.org/cgit/docs/man-pages/man-pages.git/tree/man3/endian.3#n84.
@@ -58,7 +58,11 @@
__BYTE_ORDER == __LITTLE_ENDIAN
# define _le64toh(x) ((uint64_t)(x))
# else
-# define _le64toh(x) le64toh(x)
+# if defined(__OpenBSD__)
+# define _le64toh(x) letoh64(x)
+# else
+# define _le64toh(x) le64toh(x)
+# endif
# endif
#endif