Differential pair dimensions vs. design rules confilct

in the Version: (2017-02-08 revision 0dc1193)-makepkg, release build nightly I stumbled over a design rule / differential pair dimensions issue. Perhaps its my bad, so I do not want to bother the bug list in the first place.

Issue: whenever I touch the design rules, even just checking without any changes made, I get an error (see below).

but then, I think I made the correct settings.

My bad? Bug?

your track width for differential pairs is lower than the main design rule for minimun track width

pcbnew/design rules/global design rules/minimum track width

I guess

Nope.

Looks like another floating point problem.
Can you try to create a test project where you use metric units?
(0.008 inch is 0.2032mm)

Will do in the next days. Thanks. I will use r7663, the later nightlies are painstakingly slow whenever any connectivity is touched (like adding a wire or generating a netlist) and occasionally crash in Pcbnew. But then, these are nightlies…

I am convinced this is a bug. The only thing we can do now is to find a workaround for you.
(And in this process also find out more about the bug such that a better bug report can be made.)

No need to put any effort in there for me. Firstly the project is for personal/hobbyist use only and secondly I am fine with 4.0.5 stable. Was just testing.
But thanks for your offer anyways.

Searching for bugs is not for one user only. It is there to make the software better overall.

Sure, I know. It was about the “…for you”.

Back to topic: I did some addtitional testing.

When Pcbnew starts, it ALWAYS comes up with these settings, even after changing them to - say - 0.008 and storing the project:

So it comes up with 4.9 thou, but complains about 7.8 thou and ignores the values changed in the dialogue.

Different variables used for the dialog and the check?

And there is no entry for the differential pair parameters in the xxxx-kicad_pcb. Which makes it clear why Pcbnew always starts with the same weird settings.

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