Results 1 to 8 of 8

Thread: Crash in qtgui4.dll

  1. #1
    Join Date
    Jul 2010
    Posts
    14
    Qt products
    Qt4 Qt/Embedded
    Platforms
    Unix/X11 Windows

    Default Crash in qtgui4.dll

    Hi,

    where can i find information about what is going on in the librarys from Qt.

    My appllication crashes at the adress 1a38dc in the qtgui4.dll.
    Is it possible to check which function is called, so that i can check my code why this happens?
    The debug version didn't help, because i can't run it on this machine.

    Every help is appreciated

    HeReSY

  2. #2
    Join Date
    Sep 2009
    Location
    UK
    Posts
    2,447
    Thanks
    6
    Thanked 348 Times in 333 Posts
    Qt products
    Qt4
    Platforms
    Windows

    Default Re: Crash in qtgui4.dll

    That's exactly what the debug version is for. Why can't you run it on your machine?

  3. #3
    Join Date
    Nov 2010
    Posts
    315
    Thanked 53 Times in 51 Posts
    Qt products
    Qt4
    Platforms
    Unix/X11 Windows Symbian S60 Maemo/MeeGo

    Default Re: Crash in qtgui4.dll

    In Qt Creator (or other IDE) run your application in debug mode (play button with beetle on top of it).
    When crush happens, you should be able to see call stack in IDE and locate where is problem in your application.

  4. #4
    Join Date
    Jan 2006
    Location
    Munich, Germany
    Posts
    4,714
    Thanks
    21
    Thanked 418 Times in 411 Posts
    Qt products
    Qt3 Qt4 Qt5 Qt/Embedded
    Platforms
    Unix/X11 Windows

    Default Re: Crash in qtgui4.dll

    Most probably you don't even need to dwell in the Qt lib since the problem is probably in your code, just the crash it self happens in Qt.
    Run your app in a debugger, and see which is the last line in your code before the crash - this is where your problem is.
    ==========================signature=============== ==================
    S.O.L.I.D principles (use them!):
    https://en.wikipedia.org/wiki/SOLID_...iented_design)

    Do you write clean code? - if you are TDD'ing then maybe, if not, your not writing clean code.

  5. #5
    Join Date
    Jan 2008
    Location
    Alameda, CA, USA
    Posts
    5,233
    Thanks
    303
    Thanked 864 Times in 851 Posts
    Qt products
    Qt5
    Platforms
    Windows

    Default Re: Crash in qtgui4.dll

    Quote Originally Posted by high_flyer View Post
    Most probably you don't even need to dwell in the Qt lib since the problem is probably in your code, just the crash it self happens in Qt.
    Run your app in a debugger, and see which is the last line in your code before the crash - this is where your problem is.
    Well usually, but not always. If memory has been corrupted earlier by some application code, the problem may not show up until the corrupt memory is accessed. In general though, knowing which line in the app causes the crash usually points in the right direction.

    I remember a colleague of mine who spent days debugging through the Motif libraries because he was convinced the code was buggy. Of course, it was his code that was at fault...

  6. #6
    Join Date
    Jan 2006
    Location
    Munich, Germany
    Posts
    4,714
    Thanks
    21
    Thanked 418 Times in 411 Posts
    Qt products
    Qt3 Qt4 Qt5 Qt/Embedded
    Platforms
    Unix/X11 Windows

    Default Re: Crash in qtgui4.dll

    Well usually, but not always.
    Did I say always?
    I said probably!
    ==========================signature=============== ==================
    S.O.L.I.D principles (use them!):
    https://en.wikipedia.org/wiki/SOLID_...iented_design)

    Do you write clean code? - if you are TDD'ing then maybe, if not, your not writing clean code.

  7. #7
    Join Date
    Jan 2008
    Location
    Alameda, CA, USA
    Posts
    5,233
    Thanks
    303
    Thanked 864 Times in 851 Posts
    Qt products
    Qt5
    Platforms
    Windows

    Default Re: Crash in qtgui4.dll

    I guess I meant to say that the problem may not be
    the last line in the code before the crash
    . However, crashes are almost always the programmer's fault. Except in my code, of course...

  8. #8
    Join Date
    Jul 2010
    Posts
    14
    Qt products
    Qt4 Qt/Embedded
    Platforms
    Unix/X11 Windows

    Default Re: Crash in qtgui4.dll

    Thanks for the answers.

    I hope i find the crash. I had a memory leak in my application, and sometimes it crashes.
    That never appears on my machine, because my machine had much more ram than the testmachine.

Similar Threads

  1. Runtime error QtGui4.dll VS2008
    By mbisotto in forum Installation and Deployment
    Replies: 3
    Last Post: 20th October 2010, 19:52
  2. Crash gracefully? No crash!
    By lni in forum Qt Programming
    Replies: 0
    Last Post: 7th July 2010, 03:59
  3. how to optimize the size of QtCore4.dll and QtGui4.dll
    By lovelypp in forum Qt Programming
    Replies: 1
    Last Post: 13th July 2008, 11:28
  4. qtgui4.dll error in visual c++ 2005
    By Comptrol in forum Installation and Deployment
    Replies: 33
    Last Post: 19th June 2008, 07:18
  5. Compiling QtCore4 and QtGUI4 as small as possible
    By pkirk25 in forum Qt Programming
    Replies: 5
    Last Post: 8th December 2006, 21:50

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Digia, Qt and their respective logos are trademarks of Digia Plc in Finland and/or other countries worldwide.