## Debug problems with qt 5.1.0 plugins

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peri
Posts: 3
Joined: 26 Feb 2014, 18:04

### Debug problems with qt 5.1.0 plugins

I am running windows 7 and qt 5.1.0 using mingw and there are no other compiler installed. The qt is installed from offlineinstaller in the qt-archive .My problem is, that I cannot debug qt plugins namely v_repExtMtb.dll. I have recompiled Vrep the 3 systemplugins and vrep.exe to qt 5.1.0 and everything works fine. Only thing is ,that my V_rep.dll and Vrep.exe are somewhat smaller (8609KM to 10599KB and 98 to 184KB). I have also compiled v_repExtMtb.dll in release and it works fine. Here is what I do, when I debug. I build the debug and then I copy the installationdirectory (-the programming folder and v_repExtMtb.dll) to the debug directory. I set the vrep.exe file in the debug directory to be attached and the working directory to debug. When I start debugging, Vrep starts, but does not return an application screen. In qt it stops at a brakepoint in access, where I can see debuginformation. The problem is that vrep.exe crashes when it meets my V_repExtMtb.dll. What am I missing.

Thank you Coppelia for an amazing virtual world.
Best regards Peri Stant

coppelia
Posts: 7691
Joined: 14 Dec 2012, 00:25

### Re: Debug problems with qt 5.1.0 plugins

Hello Peri,

difficult to say what is going wrong.
You could try to temporarily remove the UI part from the v_repExtMTB plugin (meaning also compiling it without QT += widgets) and see if you still run into the same kind of problem. Also, remove the speed optimization flags for the debug operation (-O3)

Cheers

peri
Posts: 3
Joined: 26 Feb 2014, 18:04

### Re: Debug problems with qt 5.1.0 plugins

Hello Forum
I have done according to your advises, but it does not work. When I debug v_rep.exe I can see where it crashes, namely simloadmodule inside Vrep Library.
The crash only happens, when i debug. If I do not get advise, I will have to proceed in another direction. Either I have to install qt4.83 and an old copy of vrep or obtain a license for Qt5.1.1. Before making that decision I would like to know if Qt4.83, now available open source, works stablely with an old vrep?

Best regards Peri

coppelia
Posts: 7691
Joined: 14 Dec 2012, 00:25

### Re: Debug problems with qt 5.1.0 plugins

Peri,

when debugging, try to remove all plugins, and see if you can debug fine. Then, keep just the one plugin and see if you can debug fine. If not, try simplifying it to the extreme (by keeping all 3 entry points empty), until you can debug it.
I guess your problem is more linked to the Qt setup/debugger setup, than V-REP, and I am not sure whether switching to a different Qt release might resolve your problem.

Cheers

peri
Posts: 3
Joined: 26 Feb 2014, 18:04

### Re: Debug problems with qt 5.1.0 plugins

Hello forum-
I have just found out, that qt5.1.1 is available as opensource, so i have already testet it and i still can't debug. If i copy the installationfolder to the debug folder, then I can run vrep without crash but without recognition of the plugin.
If I try to debug it the applicationscreen does not appear, but i can see debuginformation in CAccess::create-NonGui, also about QObjects.

Best regards Peri