Why is sizeof(XID)==8 on AMD64?

[Clemens Eisserer]

Hi Matthieu,

Thanks for your explanation =)

> This is a mistake done 25 years ago or so. It's hard to justify it,
> but it is so. A number of things that are 32 bits on the wire
> are represented as 64 bits long at the API level on LP64 machines.

Is it considered more or less safe to store those 64-bit XIDs in 32bit
variables?
If not really required I would prefer not to change all my code.

Thanks, Clemens