Slow build speeds with sip v6

[Phil Thompson]

On 22/01/2024 22:49, Nyall Dawson wrote:
> Hi list,
> 
> When moving to sip version 6 (v6.7.12) I've noticed a massive 
> regression in
> the compile times for a large project compared with sip 4 (v4.19.25) . 
> It's
> now taking around 10 minutes for the sip-build process to complete, 
> whereas
> on sip4 it was less than a minute.
> 
> (I'm using the sip / sip6 packages from Fedora 39, but I've also had
> reports of the same performance regression for the Ubuntu packages)
> 
> Is this a known issue? Is there anything I can try to restore similar
> performance to sip 4?

sip v4 is a C implementation first written over 25 years ago and poorly 
written and difficult to maintain and enhance. sip v6.8 is the result of 
a complete re-write in Python with the aim of making it easier for the 
users of sip to be able to contribute to its further development.

So far I have concentrated on correctness and ignored performance 
completely. However for sip v7 the plan is to...

- remove all deprecated features
- move all remaining knowledge of PyQt from sip to PyQt-builder v2
- performance improvements (low hanging fruit)
- move to GitHub (issue tracker etc)

So, to answer your question, what would be really useful at this stage 
is a profile of sip-build in your particular context.

Phil