Nice to be willing to donate! I hope more people actually do, although that is between Pelle and the individual.
From Pelle's web site:
"Pelles C is totally free. However, some users may want to express their gratitude by donating some money.
If Pelles C is a major part in building a product sold for money, it seems fair (to me) to donate a little bit of that money to Pelles C - but this is never required.
Donations will help to pay for this website, my time spent on support, and any possible new versions. "I don't know that there is willingness to share donation values as you should determine the value it is to you.
I will say I have donated in 2011, 2017, 2021, and 2022. I'll probably donate again with the next version

I do not make any 'for sale' software either.
John Z