Subsurface on Opensuse Tumbleweed

[Thiago Macieira]

On Wednesday, 20 June 2018 12:35:45 PDT Martin Gysel wrote:
> I get the following backtrace:
> 
> QPainter::begin: Paint device returned engine == 0, type: 2

Thanks Martin.

I don't see anything in the backtrace belonging to Subsurface, so this appears 
to be a regular Qt regression. Turns out there were a lot of changes to 
QHeaderView earlier this year, so one of the must be at fault. I can't spot 
which one just by looking though.

To help constrain the search, do you know if this warning was printed with 
Qt 5.10 too?

> #3  0x00007ffff2724f74 in QPainter::begin(QPaintDevice*) () from
> /usr/lib64/libQt5Gui.so.5
> #4  0x00007ffff3551777 in  () from /usr/lib64/libQt5Widgets.so.5
> #5  0x00007ffff3551c0c in QHeaderView::mousePressEvent(QMouseEvent*) ()
> from /usr/lib64/libQt5Widgets.so.5

I'm trying to guess which frame is that ??, but it's not clear what it is. My 
first guess was QHeaderViewPrivate::setupSectionIndicator, which does have a 
QPainter, but that function is painting on a QPixmap and that wouldn't have 
printed the warning. But that leaves me out of options.

Can you install the debug symbols for the library?

	zypper in libQt5Gui5-debuginfo

That should resolve the ?? to something useful, and possibly also give us line 
numbers.

PS: I'm experimenting with an optimised build of Qt5 that you can find at 
https://build.opensuse.org/package/show/
home:thiagomacieira:branches:openSUSE:Factory/libqt5-qtbase

-- 
Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
   Software Architect - Intel Open Source Technology Center