Help with memory management in C++

[saikat056]

Hi guys,
I am in a problem to manage memory in c++. I just can't figure out where in my program memory leaks. I used "new" and "delete" very carefully.
1. Can anyone help me with a tool in linux to detect memory leaks?
2. Can anyone please share possible scenarios where "memory leak" may occur?

Following are my possible strategies that I applied to avoid memory leak:
1. After declaration of a pointer, I assign 0 to it.
Box * b =0;

2. Before using "new", I check whether the pointer is 0 or not.

if(!b)

b = new Box();

3. I free the memory at appropriate places:
Class Segment
{

private:
Box * b;
Box ** arrBox;

};

Segment::Segment()
{

b = new Box();
arrBox = new Box*[10];
for (int i =0; i < 10; i++)
arrBox[i] = new Box();

}

~Segment::Segment()
{

if(b)
{

delete b;
b = 0;

}
for (int i = 0; i < 10; i++)
{

if(arrBox[i])
{

delete arrBox[i];
arrBox[i] = 0;

}

}
if(arrBox)
{

delete [] arrBox;
arrBox = 0;

}

}

4. I have also avoided the case where I am initializing an object in a loop:

while(i<10)
{

b =new Box();
i++;

}

The above are the cases that I checked for memory management. Please share your ideas to have more situations where memory leak may occur.

Thanks,
Saikat

[atreyu]

I haven't looked at your code, but I can suggest Valgrind to you. It may already be available in your distro's repos.

[JohnGraham]

I'd also recommend valgrind. Also consider using smart pointers like auto_ptr to make life easier for yourself.

[Roxoff]

I believe that what you are doing here:

Segment::Segment()
{
b = new Box();
arrBox = new Box[10];
for (int i =0; i < 10; i++)
arrBox[i] = new Box();

is creating an array of 10 Box instances, then looping around and overwriting each instance in the array with a new instance created with new. This will leak memory. Perhaps instead of using an array like this, you should consider using the STL, something like std::vector or std::array should do it.

[saikat056]

The line
arrBox = new Box[10];

should be

arrBox = new Box*[10];

Thank you for help!

[saikat056]

Valgrind is very helpful. Thank you!!