Question

I am working on a video processing project using Qt and Opencv with Qt Creator IDE in Windows 7 32bit. I have been successful compiling and running my code. But when I close the gui of my application Windows pops up an error :

MyProgram.exe has stopped working


Problem signature:
  Problem Event Name:   APPCRASH
  Application Name: QtTracker3.exe
  Application Version:  0.0.0.0
  Application Timestamp:    5107b5da
  Fault Module Name:    ntdll.dll
  Fault Module Version: 6.1.7600.16695
  Fault Module Timestamp:   4cc7ab44
  Exception Code:   c0000005
  Exception Offset: 00052073
  OS Version:   6.1.7600.2.3.0.256.1
  Locale ID:    1033
  Additional Information 1: 0a9e
  Additional Information 2: 0a9e372d3b4ad19135b953a78882e789
  Additional Information 3: 0a9e
  Additional Information 4: 0a9e372d3b4ad19135b953a78882e789

I am not a professional programmer and I need not to know whether this happens because my poor programming skills or something else..

Answer 1

Exception code c0000005 is an access violation, also known as general protection fault. The program is reading from, or writing to, an address which is not part of the virtual address space. A very common cause is that you are de-referencing a stale pointer. In other words, the pointer was once valid, but you have subsequently freed it. Then later when you attempt to access it, an exception is raised.

The exception is faulting in ntdll.dll which is a system DLL. That means that something in your program is passing invalid data to a system API.

In order to solve this problem you will likely need to run under the debugger and let the debugger break at the point in the code where the exception occurs. Then you can attempt to work out why the memory that is being accessed is invalid.

That’s something that you can do, but we cannot. You have the code, we do not. So, we can’t give you any more help than this. In any case, there’s no need to despair–these problems are usually easy enough to solve with the help of a debugger.