[boost] enabling automatic memory leak detection with VC

From: Robert Ramey (ramey_at_[hidden])
Date: 2004-05-20 13:06:23

While investigating shared_ptr serialization, I've come upon the VC method
used for detecting memory leaks.  I had previously used it as part of MFC
and found it very helpful.  By including the following at the beginning of
one's test program:

#define _CRTDBG_MAP_ALLOC
#include <stdlib.h>
#include <crtdbg.h>

struct leak_reporter {
        static leak_reporter instance;
        leak_reporter(){
                _CrtSetDbgFlag ( _CRTDBG_ALLOC_MEM_DF |
_CRTDBG_LEAK_CHECK_DF );
        }
        ~leak_reporter(){
//		_CrtDumpMemoryLeaks(); // replaced by the above
        }
};
leak_reporter leak_reporter::instance;

The program displays the following in the output window while running under
the VC IDE:

Detected memory leaks!
Dumping objects ->
c:\program files\microsoft visual studio .net 2003\vc7\include\crtdbg.h(689)
: {663} normal block at 0x00325480, 24 bytes long.
 Data: < ,W             > C4 2C 57 00 00 00 00 00 FF FF FF FF 00 00 00 00 
c:\program files\microsoft visual studio .net 2003\vc7\include\crtdbg.h(689)
: {393} normal block at 0x003261F0, 24 bytes long.
 Data: < ,W             > 94 2C 57 00 00 00 00 00 FF FF FF FF 00 00 00 00 
Object dump complete.

The sequential number (663 and 393 in this example) can be used to trap the
debugger at the original allocation when the test is run the next time.

Is this not a worthy idea to be included in the test system - at least for
VC? In this way we would get a report of memory leaks every time we ran a
test.

Robert Ramey