Deprecation: argument `ul` for format specification `"%lu"` must be `int`, not `ulong`

[Walter Bright]

On 8/25/2020 2:28 AM, ParticlePeter wrote:
> The code I am talking about is unchanged since at least, dmd 2.086, 
> now I am getting the Deprecation message.

That's because printf format checking is a new feature. Your code was actually 
broken before, although it appeared to work. It would likely have failed more 
obviously if there were more argments after ul, or if your machine was bigendian.

This change uncovered a lot of similar latent bugs in programs.