[Qt-interest] How to detect memory leaks

[Santhosh Y]

> I think you can use _CrtMemCheckpoint, _CrtMemDifference to detect 
> memory leak on Windows.

Please see my below main(); Here I declared a variable s1,s2,s3, and I 
used with *CrtMemCheckpoint & * *CrtDumpMemoryLeaks** *as shown below
=================================================
*_CrtMemState  s1;  // Global declaration*
*_CrtMemState  s2;  // Global declaration*
*_CrtMemState  s3;  // Global declaration*

int main(int argc, char **argv)
{
     QApplication app(argc, argv);
     Q_INIT_RESOURCE(gui);

*    _CrtMemCheckpoint(&s1);*

     NewGUICOMObj appobject(argv[0]);
     if (appobject.createInstance() == -1) {
         // failure in create instance call
         return -1;
     }


     //successfully launched event loop
     int value =   app.exec();

*    _CrtMemCheckpoint(&s2);*


      if(_*CrtMemDifference(&s3, &s1, &s2)*)
        {
       printf("\nOOps! Memory leak detected\n") ;
*      _CrtDumpMemoryLeaks() ; *
       // alternatively you can use _CrtMemDumpAllObjectsSince for

       //dumping from specific check point

        }

     return value;
}
=================================================

/// output is :-

Dumping objects ->
{166167} normal block at 0x0ED00018, 16 bytes long.
  Data: <  Z 0 Z 0 Z    e> B8 B1 5A 02 30 85 5A 03 30 85 5A 03 C4 CC B2 65
{163467} normal block at 0x0ECFB9B8, 80 bytes long.
  Data: < ~ > D0 7E CF 0E 00 0C 00 A0 01 08 00 A0 00 02 00 00
{162176} normal block at 0x0ECFB508, 124 bytes long.
Object dump complete.


*How to read the above output. How to make out where the 16 bytes memory 
leak is present in my source code!*
Please tell me is this the correct way of doing this.

Thanks

>
> For Linux, since there is no similar API to do the heap check, you can 
> use Valgrind (|VALGRIND_COUNT_LEAKS)
>
> Regards
>
> Johnson
>
>
>
>
> |
> On Mon, Jul 12, 2010 at 4:46 PM, Santhosh Y <santhosh at softjin.com 
> <mailto:santhosh at softjin.com>> wrote:
>
>     Hi,
>
>     How to see memory leaks in my Qt application. Would like to know
>     the amount of memory leak in my application.
>
>     I am working on Windows OS,  using
>
>         1. Microsoft Visual Studio 2008
>             Version 9.0.21022.8 RTM
>             Microsoft .NET Framework
>             Version 3.5 SP1
>         2. Qt 4.5.2 version
>
>     1. Any idea of how to run purify for a Qt application.
>     2. Any flags to be added to the project file / Visual studio for
>     detecting memory leaks?
>
>     Thanks in advance.
>
>     Regards,
>     Santhosh
>
>     -- 
>     ----------------------------------------------------
>     Y Santhosh Kumar -
>     Senior Software Engineer,
>     SoftJin Technologies Pvt Ltd,
>     www.softjin.com  <http://www.softjin.com>
>     ----------------------------------------------------
>          
>
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> -- 
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> ____________________________
> Keep it simple, stupid


-- 
----------------------------------------------------
Y Santhosh Kumar -
Senior Software Engineer,
SoftJin Technologies Pvt Ltd,
www.softjin.com
----------------------------------------------------



Business Disclaimer
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If  you  are  not  the  intended recipient please be advised that you have
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