timingdiagram crash if dataset not present

[guitorri]

Issue: crash when trying to load a schematic containing a timingdiagram for which the dataset is missing. Reproduce: see attached files https://gist.github.com/guitorri/c204875db4ae20f89584

With 0.0.18 it loads and empty diagram. If you run with 0.0.18 it fills the diagram with data. With master if you try to open the attached .sch (or delete the dataset vhdl_vector.dat and open) the schematic with it crashes with (OSX):

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   org.qucs                        0x00000001054c363c Q3GList::count() const + 12 (q3glist.h:160)
1   org.qucs                        0x000000010590e0f5 Q3PtrList<DataX>::isEmpty() const + 21 (q3ptrlist.h:88)
2   org.qucs                        0x000000010592c99a TimingDiagram::calcDiagram() + 3178 (timingdiagram.cpp:171)
3   org.qucs                        0x00000001058fb05b Diagram::updateGraphData() + 43 (diagram.cpp:809)
4   org.qucs                        0x00000001058f930a Diagram::loadGraphData(QString const&) + 986 (diagram.cpp:771)
5   org.qucs                        0x00000001054e0844 Schematic::reloadGraphs() + 212 (schematic.cpp:1275)

[yodalee]

Can you see #28 I ran to a similar situation then. Maybe it's related?

[guitorri]

It looks like the same issue. Right now it points to: https://github.com/Qucs/qucs/blob/master/qucs/qucs/diagrams/timingdiagram.cpp#L171 Graph was ported to QList but cPointsX is still Q3PtrList.

[yodalee]

I use same way to send the patch, but maybe it's not the best way to do this.

[guitorri]

Your patch seems good.

[yodalee]

It's just a copy and paste (._.)

[guitorri]

Hehe, now I understood, you took it from the previous fix on truthdiagram.... :)

[guitorri]

Fixed in ad1ac336fa, thanks!