Potential memory leak in QSignalMapper : Qt version 6.3.0

BigBen

Hi, I have the following code, using QSignalMapper:

QSignalMapper* myMapper = new QSignalMapper(this);

        for(int j=0;j<myList.size(); j++){
            connect(myList[j]->timer, SIGNAL(timeout()), myMapper, SLOT(map()));
            myMapper->setMapping(myList[j]->timer, j);
            connect(myMapper, SIGNAL(mapped(int)), this, SLOT(up(int)));
        }

However, this is not working, and giving me the warning:

potential leak of memory pointed to by 'myMapper'

I don't understand why this is not working, and why I am getting the memory leak warning.

I am using Qt version 6.3.0

Thanks

SGaist

Hi,

What exactly is not working ?

As for the warning, you declared myMapper somewhere and never delete it hence the warning. myMapper having a parent means that it will be deleted at some point when the parent is deleted however your tool is likely not aware of that.

BigBen

@SGaist
The up() slot is supposed to show a video in a label. It does not do that with this code.

I am using Qt Creator. Is there some way I can fix something to get rid of this warning?

I was wondering if this has got something to do with the Qt version. Since the same code is working properly in Qt version 5.

SGaist

Not knowing what tool you are using I can't answer for the warning.

As for the slot, did you check that it has been called ?
How are you managing that video ?

mranger90

@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