assertion failed when use mp_encode_int

[stdanley]

hello, all
I have been using this libray, but failed at encode_int. when I looked into the code, I found:
"
MP_IMPL char *
mp_encode_int(char *data, int64_t num)
{
assert(num < 0);
if (num >= -0x20) {

"
what's the reason to force "num <0"

[rtsisyk]

Please use encode_uint for unsigned numbers.

[Totktonada]

The story is in #1.