[Qt-interest] QWidget: Must construct a QApplication before a QPaintDevice

[Brad Howes]

On Aug 31, 2009, at 11:22 AM, Andre Somers wrote:

> I am experiencing a weird problem. When I compile my program with the
> release flag, I get the above error if I run it through the  
> debugger. If
> I run it directly, it aborts with a code 3. However, when I compile a
> debug version of my program, the problem does not occur.


What compiler/OS are you running on? In my experience, crashes that  
occur in an optimized build (I assume that is what you mean by  
'release') vs. a debug build happen due to uninitialized memory or  
invalid parameter count -- a quite common one in my C days was printf 
() bugs. For C++, a couple of things come to mind: uninitialized POD  
members, invalid assumptions on object lifetimes, race condition.

Brad

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Brad Howes
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