@Axel-Spoerl said in A Strange Qt and postgresql problem ! when using Kaspersky:

If everything is configured properly and you use pgsql > 10.7, the only idea I have is that Kaspersky (partly) blocks network traffic coming from an executable, which it doesn't know. But that's where my knowledge ends and you have to turn to the Kaspersky support.

Thank You so much bro <3 for great support
by the way i am using postgresql version 14 the latest one

i agree with you there's a problem on kaspersky they partly affect any unsigned software when connecting to postgresql ... (kaspersky set my tested softwares as (low restricted which is the best group when application doesn't have digital signature) in application control

Low Restricted. This group includes applications for which the following conditions are met: Applications are not digitally signed by trusted vendors. Applications are not recorded in the trusted applications database of Kaspersky Security Network.

@BigBen said in Potential memory leak in QSignalMapper : Qt version 6.3.0:

connect(myMapper, SIGNAL(mapped(int)), this, SLOT(up(int)));

I'm pretty sure that this:
connect(myMapper, SIGNAL(mapped(int)), this, SLOT(up(int)));

should not be done in the loop.
There should only be one connect of the mapper to the receiving object

@leonardoMB

Ok never mind. Using latest of the greatest (Qt 5.15.9) seems to solve the problem. No leaks detected.

@Christian-Ehrlicher Thanks for tracking that down. Hope Qt gets it fixed soon.

@Roysten-Rigobert Why don't you create menu/actions at once by making menu as member variable?

and in contextMenu(QPoint) slot call only the menu->exec(mapToGlobal(pos));

@SpaceToon said in Replacing QList of objects with QLIst of pointers to these objects:

why in my solution with the pointers an exception occurs.

Because the pointer you store a dangling - the object behind is already deleted when deviceDiscovered() is finished (or a little bit later, don't know the code which calls this function).

You need to add extra logic in your prog.

Your problem seems very similar to the Copy/Cut/Paste logic. You don't know if the paste command is valid because you don't know if the user press copy command before that.
Well, is up to you to register the states of this commands.

So you need to implement the logic suitable to your case, for example, if the list of items is empty, obviously you cannot edit it, etc.

About the interfaces (as others said), create them on the fly could be tricky and error prone. You can do it if only minor changes are to be made (hide/disable a few button/options)
If the interfaces are very different, better way to create a unique persistent widget for each, and put them in a StackedWidget.

Good luck :;)

@legitnameyo
Although what @Kent-Dorfman says about stack-allocated destructor auto-closing is quite correct, I would always put in an explicit close() as soon as I am finished with any file, personally. It's good practice, especially for potential future code changes. You never need flush() on read, and you don't need flush() on write if it's immediately followed by close().

@fcarney I can't beleive I missed your question. Comparing with Heob, Deleaker provides more features like taking snapshot at any moment, and comparing them later. Besides heap allocations, Deleaker also tracks COM/ActiveX/GDI/USER32 leaks etc.

@aha_1980

That's what I thought. If I manually start valgrid it runs fine, it produces a report as well.
I just wanted to make it work with Qt because it looks more convenient.

I'll try updating Qt creator later on.

Thanks

Just by loading one page and coming back, we can't make out the memory leak. Try multiple times like this. If you see a increase & no decrease then we can conclude memory leak. If you can send me the complete example, we can try as well.

Hi @wthung, I don't think this forum supports file uploads.

Can you create a simple example that demonstrates the memory leak? Just post the code here, no need to upload an attachment.

Like I already wrote, it has nothing to do with Qt. Qt is a C++ framework, it doesn't do anything special with respect to memory management.

So yes, since the OP wrote that the memory was not freed after the application ended then he needs to elaborate on that.

Hi and welcome to devnet,

That version of QtJambi is not part of Qt. In fact QtJambi has been deprecated a long time ago and the version you are using is a community edition. You should ask the authors of it directly.

@Stefan-Monov76
The automatic deletion of QObject childs by the parents is used in whole Qt frame work and
is fully documented and will not change in any version.
http://doc.qt.io/qt-5/objecttrees.html

Thanks Wieland for taking a look. And thanks for the mailing list suggestion! Good to know of more Qt resources.

I've filed a bug: https://bugreports.qt.io/browse/QTBUG-56774

@Wieland No, we are using the <video> tag in HTML5, together with JS to play webM format video. With 5.6, the video goes up all the time till the system crashes.

The problem is disappeared in 5.7 with newer Chromium core, but it leads out a new problem as indicated the https://bugreports.qt.io/browse/QTBUG-53411.

When we use 5.7, the memory is fairly stable, but then after the first run, the JS will fail to work with the application due to a bug in QwebchannelTransport.

We tried to build QT from source code, but the WebEngine won't build (see my other post).

We are looking for a compiled WebEngine module with the bugs fixed as indicated in the QTBug-53411.

Thank you.