Using int64 on a lower bit data class

Using int64 to convert from a 32-bit to int64 data class, essentially adding 0 bytes to extend the class.

Apart from extra space being used, are there any other negatives to doing this? I would assume no resolution is lost as all the original data is still stored in the int64 class.

Answer 1

[Walter Roberson]

int64() of int32 data just sign extends

int64() of uint32 data just zero extends

uint64() of int32 data would result in 0 for any negative data because of saturation

uint64 of uint32 data would just 0 extend.

[James Best]

Thanks for your help, this makes a lot more sense now.