Hi,

To convert between OCaml Int64 and C Integer, I think uint64_t or
int64_t can be the target C type. Int64_val is the macro converting
OCaml value to int64, I failed to find the macro for the other
direction under ./byterun. ./byterun/ints.c defines operations on
int64, caml_copy_int64(I64_of_intnat(..)) seems to be working for such
conversion? But mlvalues.h does not declare them to use. How can I
convert int64 to value?

Thanks
-- 
Jianzhou