I downloaded a trial version, and it sucks.
C++, 64 bit.
I commented out a delete statement as the simple test, and
VS 2010 compiler points to memory leaks, and this expensive tool is way off - points me to some DLLs and
handles that are actually properly disposed of.
I did not change any parameters, just ran "Memory error analysis/detect leaks".
What gives?
Am I doing something wrong?
Please advise,
Thank you
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You could also try a different analysis type ("Detect Memory Problems" or "Locate Memory Problems"). These use a slightly different instrumentation approach than "Detect Leaks", and may give different results.
Mark,
I didn't hear anything about Unreachable Leaks. Could you provide aC or C++ test case, please?
Best regards,
Sergey
#include
int *make_unreachable_leak()
{
// Will be reported by Inspector XE
int *tmp = (int *)malloc(sizeof(int));
return NULL;
}
int *make_reachable_leak()
{
// Still accessible through global pointer
// Will not be reported by Inspector XE
int *tmp = (int *)malloc(sizeof(int));
return tmp;
}
int *ptr;
int main(int argc, char **argv)
{
make_unreachable_leak();
ptr = make_reachable_leak();
return 0;
}
int *make_reachable_leak()
{
// Still accessible through global pointer
// Will not be reported by Inspector XE
int *tmp = (int *)malloc(sizeof(int));
return tmp;
}
...
Mark,
>>// Will not be reported by Inspector XE
I think it has to be fixed because this is wrong. In both cases memory is allocated from a heap and
a Win32 API function 'HeapAlloc' is used. I will provide two reports from built-in Memory Leaks detection systems
implemented by Microsoft and for the ScaLib project.
Best regards,
Sergey
[cpp]... RTint *g_iPointer = RTnull; RTint * MakeUnreachableLeak( RTvoid ) // Will be reported by Inspector XE { // RTint *iTmp = ( RTint * )malloc( sizeof( RTint ) ); // RTint *iTmp = ( RTint * )new RTint( 777 ); RTint *iTmp = ( RTint * )CrtNew RTint( 777 ); return ( RTint * )RTnull; } // Accessible through global pointer RTint * MakeReachableLeak( RTvoid ) // Will not be reported by Inspector XE { // RTint *iTmp = ( RTint * )malloc( sizeof( RTint ) ); // RTint *iTmp = ( RTint * )new RTint( 777 ); RTint *iTmp = ( RTint * )CrtNew RTint( 777 ); return ( RTint * )iTmp; } ... ... // Sub-Test 2.1 - Microsoft MLD { RTbool bOk = RTfalse; _CrtSetDbgFlag( _CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF ); _CrtSetReportMode( _CRT_ERROR, _CRTDBG_MODE_DEBUG | _CRTDBG_MODE_WNDW ); MakeUnreachableLeak(); g_iPointer = MakeReachableLeak(); _CrtDumpMemoryLeaks(); } ... or ... // Sub-Test 2.2 - ScaLib MLD { RTbool bOk = RTfalse; MakeUnreachableLeak(); g_iPointer = MakeReachableLeak(); bOk = MemoryTracerData(); bOk = MemoryTracerIntegrity(); } ... [/cpp]
Note: MLD stands for Memory Leaks Detection.
Here are results:
>> Microsoft MLD - CRT-function 'malloc' is used <<
...
Detected memory leaks!
Dumping objects ->
{76} normal block at 0x02124470, 4 bytes long.
Data: < > CD CD CD CD
{75} normal block at 0x02124430, 4 bytes long.
Data: < > CD CD CD CD
Object dump complete.
...
>> Microsoft MLD - C++ operator 'new' is used <<
...
Detected memory leaks!
Dumping objects ->
{76} normal block at 0x02124470, 4 bytes long.
Data: < > 09 03 00 00
{75} normal block at 0x02124430, 4 bytes long.
Data: < > 09 03 00 00
Object dump complete.
...
>> ScaLib MLD - C++ operator 'CrtNew' is used ( the same as 'new' ) <<
...
* Memory Block: 0 *
..\common\prttests.cpp(6527)
Memory Block State: 1 - Allocated by CrtNew
* Memory Block: 1 *
..\common\prttests.cpp(6534)
Memory Block State: 1 - Allocated by CrtNew
Memory Blocks Allocated : 2
Memory Blocks Released : 0
Memory Blocks NOT Released: 2
Memory Tracer Integrity Verified - Memory Leaks Detected
...
...
Detected memory leaks!
Dumping objects ->
{76} normal block at 0x02124470, 4 bytes long.
Data: < > CD CD CD CD [SergeyK] Not initialized by 'malloc'
...
>> Microsoft MLD - C++ operator 'new' is used <<
...
Detected memory leaks!
Dumping objects ->
{76} normal block at 0x02124470, 4 bytes long.
Data: < > 09 03 00 00 [SergeyK] Initialized with a value 777 ( 0x00000309) by 'new'
...
Best regards,
Sergey
Here is good tutorial for the memory leaks detection with the help of windbg : http://www.codeproject.com/Articles/31382/Memory-Leak-Detection-Using-Windbg
can you save a lot of pain caused by manually walk the heap...
In 2007 I worked for an image processingproject and it had more than 30,000 memory leaks...
Some developers / users on the forumare dealing with even more memory leaks, something like 100,000, and
take a look at posts...
WinDbg is a great externalutility but it is not integrated with a Visual Studio IDE by default.
Intel Inspector XE, or Microsoft Memory Leaks Detection ( MLD )API of the CRT library, orScaLib MLD APIare able to point
exactly to a source line where a memory was allocated ( because they could beintergated, or already integrated by default,
withVS IDE )and in that case adeveloper doesn't need to "walk the heap" trying to find something suspicious.
On middle- or large-scale software projects developers arealwaysbusy with completely different things related to
implementation of somenew functionality, or stabilization of some codes, etc.
Here is a short example:
...
* Memory Block: 0 *
..\common\prttests.cpp(6527) [SergeyK]It reports to a line where a new C++ operator was used
Memory Block State: 1 - Allocated by CrtNew
* Memory Block: 1 *
..\common\prttests.cpp(6534) [SergeyK]It reports to a line where a new C++ operator was used
Memory Block State: 1 - Allocated by CrtNew
Memory Blocks Allocated : 2
Memory Blocks Released : 0
Memory Blocks NOT Released: 2
Memory Tracer Integrity Verified - Memory Leaks Detected
...
Best regards,
Sergey
Windbg will be integrated with the next release of Visual Studio.WinDbg is a great externalutility but it is not integrated with a Visual Studio IDE by default
>>and in that case adeveloper doesn't need to "walk the heap" trying to find something suspicious
@Sergey I was talking from the "debugging" point of view:)
Btw I have used extensively windbg and I must say that this tool is outstanding and very versatile.
>> middle- or large-scale software projects developers arealwaysbusy with completely different things related to
implementation of somenew functionality, or stabilization of some codes
Who is responsible for software - OS interaction debugging when something goes wrongand who do it atmachine code level ?
A manager... Because he/shetells software developers what they should do and what they shouldn't... :)
Best regards,
Sergey
