It seems obvious now, but of course there was no warning and I
simply could not spot the error among all the other changes I
had made. Gah.
Can we just please give up on Qt4 already and start using
Qt5-style signal/slot connections that would catch this kind of
error at compile time?
We discussed dropping support for Qt4 back in March and June of
this year. I think most of us agreed that it was a good idea
but we haven't followed through.
If we agree that this is the right move for 6.1, then I'm
willing to do most or all of the work to fix the configure
script and start updating the sources immediately. If we delay,
I think we will have to wait until after the 6.1 release as this
is a fairly big change so deserves sufficient time for testing.
No objection. The last Qt4 release was December, 2011 or
approximately 8 years ago. Even most long-term release
distributions provide only 3 or 5 years support, so the number of
users for Octave who require this feature is already very small.