QTextEdit memory leak : is this a bug?

[Wing_Zero]

Hi at all,
the issue i'm having with a simple program, is as simple as terrifying.

My app is a dialog with 6 QTextEdit form.
Every time a push a button i first clear (QTextEdit::clear() ) all the forms and then i set up the string (QTextEdit::setText("foo")).

Every time one of these 2 operations it is execuded the memory amount increases without never decrease.(also if I do online the Clear method).

This is definietly a memory leak, but that' certinly not my fault.

How I'm wrong? It is this the way that QTextEdit is supposed to work?

Googling a little bit I've found this:

http://lists.trolltech.com/qt-interest/2001-10/thread01084-0.html

That's exactly my issue, but no one replies with a solution.

Thanks in advance to anyone who will try to help me :)
And, as usual, sorry for my bad english.

Wing

[Ginsengelf]

Hi, are you sure it's not the UndoRedo function? Set

setUndoRedoEnabled(false) for the QTextEdit objects and try again.

Ginsengelf

[Wing_Zero]

Thanks for the answer.
I Think that this was the right solution to my problem... but wei i setted undeRedo false for all of my QTextEdit nothing's changed. It do the same thing. A bad memory leak.

[lsvichet]

Hi all,
I have this problem too. :crying:

[ChrisW67]

Congratulations ;)

What Qt version? Compiler? What have you tried? What are you doing exactly?

Post a small, compilable example that demonstrates the problem. We have yet to see any code and referenced mailing list thread is talking about Qt 3.0.0.

[lsvichet]

For me, i used Qt 4.7.0 32 bits on Windows 7 64 bits. Here is an example:


#include <QApplication>
#include <Qt/qtextedit.h>

int main(int argc, char* argv[])
{
QApplication app(argc, argv);
QTextEdit *text=new QTextEdit;
text->resize(400,400);
text->setUndoRedoEnabled(false);
text->show();

return app.exec();
}

i) When i compile the code, i see in windows task manager that the memory used (by the exe result from this code ) is 12,700 K
ii) i copy a large text from notepad and past into textedit field, the memory used become : 13,500 K
iii) I move the cursor back/forward inside the text by arrow key, the memory used increased to : 16,100 K. I wait for a minute and it still 16,100 K.
iv) i delete the text that i just past from textedit field, the memory used is still 14,000 K. I wait for many minutes and it is still 14, 000 K.
v) if i continue past/delete manay time the memory used will increase more and more like: to 24, 000 K and it can be bigger than that.

[MarekR22]

Releasing memory in program doesn't mean that system will regain this memory! Most of compilers (not only C++) moves released memory to a pool for future reuse to improve performance.
So you can't relay on system information about application memory consumption. You have to have some better proof of memory leak!

[FelixB]

btw, as long as you don't delete your QTextEdit you're creating a memory leak by yourself ;)

[stampede]

if i continue past/delete manay time the memory used will increase more and more like: to 24, 000 K and it can be bigger than that.
Can you crash the app this way, just by paste & delete text in QTextEdit ? ( sorry, I don't have the time to test it :) )