Re: [Interest] Use Qt release DLLs while debugging application
On Tuesday, 24 April 2018 22:35:00 PDT Rainer Wiesenfarth wrote: > Note: You have to make sure that any other library you link against is > using the same C runtime And that's exactly the problem. With MSVC, the definition of "debug" and "release" can take one of two meanings: optimised or not versus the runtime it's linking against. By default, people build non-optimised code (/Od) with debugging symbols (/Zi) against the debug runtime (/MDd). But you can compile optimised code (/O2) against the debug runtime (/MDd) and you can compile non- optimised code with debugging symbols (/Od /Zi) against the release runtime (/MD). -- Thiago Macieira - thiago.macieira (AT) intel.com Software Architect - Intel Open Source Technology Center ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Use Qt release DLLs while debugging application
On 2018-04-25 07:35, Rainer Wiesenfarth wrote: *You can, if* you are interested in the debug code of your application only, but not in the one of Qt and the C runtime. If you use the release version of Qt, you have to make sure that you link with the same runtime, i.e. you use /MD (Mulit-threaded DLL) for your debug build instead of /MDd (Multi-threaded Debug DLL). Note: You have to make sure that any other library you link against is using the same C runtime Note: I have no idea how to configure this using QMake (we use hand-crafted .vcxproj and .props) Cheers, Rainer Morning, just want to add, qDebug() output works fine in Release builds also. I.e. just printf()-style debugging but sometimes that's all you need. Rgrds Henry ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Use Qt release DLLs while debugging application
On Tue, Apr 24, 2018 at 10:34 PM, Thiago Macieira wrote: > On Monday, 23 April 2018 22:34:20 PDT Hamish Moffatt wrote: > > This must be an FAQ, but can I use the Qt release mode DLLs while > > running my application compiled for debug? (In Visual Studio 2015, Qt > 5.8). > > > [...] > > > You can't do that because of Microsoft (see Gunnar's reply). > [...] > This is only half the truth: *You can, if* you are interested in the debug code of your application only, but not in the one of Qt and the C runtime. If you use the release version of Qt, you have to make sure that you link with the same runtime, i.e. you use /MD (Mulit-threaded DLL) for your debug build instead of /MDd (Multi-threaded Debug DLL). Note: You have to make sure that any other library you link against is using the same C runtime Note: I have no idea how to configure this using QMake (we use hand-crafted .vcxproj and .props) Cheers, Rainer -- Software Engineer | Trimble Imaging Division Rotebühlstraße 81 | 70178 Stuttgart | Germany Office +49 711 22881 0 | Fax +49 711 22881 11 http://www.trimble.com/imaging/ | http://www.inpho.de/ Trimble Germany GmbH, Am Prime Parc 11, 65479 Raunheim Eingetragen beim Amtsgericht Darmstadt unter HRB 83893, Geschäftsführer: Dr. Frank Heimberg, Jürgen Kesper ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Use Qt release DLLs while debugging application
On Monday, 23 April 2018 22:34:20 PDT Hamish Moffatt wrote: > This must be an FAQ, but can I use the Qt release mode DLLs while > running my application compiled for debug? (In Visual Studio 2015, Qt 5.8). > > I looked through the mkspecs and it doesn't seem possible. The > qtPlatformTargetSuffix function defined in qt_functions.prf always adds > the d suffix when compiling for debug. > > > I ask because I'm not debugging Qt, and the XML parsing in Qt5Xml seems > to be horrendously slow in debug mode. It's using 45% of my total CPU > time, versus 11% in release mode. I'm not actively debugging anything > remotely related to XML but this is killing debug time for me. You can't do that because of Microsoft (see Gunnar's reply). But you can recompile the debug library with optimisation enabled. Or you can compile your release binary without optimisations and with debug symbols. Exercise left to the reader. -- Thiago Macieira - thiago.macieira (AT) intel.com Software Architect - Intel Open Source Technology Center ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
Re: [Interest] Use Qt release DLLs while debugging application
I would recommend setting the /Zo option for enhanced debugging information in your application release build. ( is default in vs 2017). Alternatively you can change disable your optimisation in release build with /Od. you CANNOT use a qt application debug build with Qt realease dlls, because that will crash , due to using a mix of release and debug c-runtime dlls, which have different memory allocators. The debug c runtime will allocate extra bytes for debugging purposes, which the release allocator does not know of. So it crashes if you allocate with the debug allocator and delete with the release allocator or vice versa. Regards, Gunnar Roth -- Original Message -- From: "Hamish Moffatt" To: "interest@qt-project.org" Sent: 24/04/2018 07:34:20 Subject: [Interest] Use Qt release DLLs while debugging application This must be an FAQ, but can I use the Qt release mode DLLs while running my application compiled for debug? (In Visual Studio 2015, Qt 5.8). I looked through the mkspecs and it doesn't seem possible. The qtPlatformTargetSuffix function defined in qt_functions.prf always adds the d suffix when compiling for debug. I ask because I'm not debugging Qt, and the XML parsing in Qt5Xml seems to be horrendously slow in debug mode. It's using 45% of my total CPU time, versus 11% in release mode. I'm not actively debugging anything remotely related to XML but this is killing debug time for me. Hamish ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
[Interest] Use Qt release DLLs while debugging application
This must be an FAQ, but can I use the Qt release mode DLLs while running my application compiled for debug? (In Visual Studio 2015, Qt 5.8). I looked through the mkspecs and it doesn't seem possible. The qtPlatformTargetSuffix function defined in qt_functions.prf always adds the d suffix when compiling for debug. I ask because I'm not debugging Qt, and the XML parsing in Qt5Xml seems to be horrendously slow in debug mode. It's using 45% of my total CPU time, versus 11% in release mode. I'm not actively debugging anything remotely related to XML but this is killing debug time for me. Hamish ___ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
