Array deletion

[Fatboy]

What happens if you don't delete arrays that you've declared and defined? Is there any harm done to the memory of the computer?


Another problem is that when I declare arrays as class members, everything works fine. But when I try to delete the arrays in the destructor of the class, the program runs but also gives an assertion error!!! Why?

[HighCommander4]

You're only supposed to delete arrays that you allocated memory for using new or new[]. Deleting static arrays (arrays not allocated with new or new[]) is undefined behaviour.

[Krzemo]

If U delete array (created with new operator !!!) u should do it that way:

 int *pArray= new int [10];
...
delete [] pArray;

Best regards,
Krzemo.

[Fatboy]

Oh! I didn't know that I only need to delete static arrays, thank you.

[Krzemo]

Oh! I didn't know that I only need to delete static arrays, thank you.

It should be:

Oh! I didn't know that I only need to delete nonstatic arrays, thank you.

[cilu]

See this FAQ about memory leaks.

Do not make the confussion between statically declared arrays

char array[10];

and static arrays:

static char array[10]; //static statically declared array
static char* parray = new char[..]; // static dinamically declared array

When modifying a variable, the static keyword specifies that the variable has static duration (it is allocated when the program begins and deallocated when the program ends) and initializes it to 0 unless another value is specified. When modifying a variable or function at file scope, the static keyword specifies that the variable or function has internal linkage (its name is not visible from outside the file in which it is declared).

A variable declared static in a function retains its state between calls to that function.

When modifying a data member in a class declaration, the static keyword specifies that one copy of the member is shared by all instances of the class. When modifying a member function in a class declaration, the static keyword specifies that the function accesses only static members.

[wien]

To cut it short... When you new you delete, when you new[] you delete[], and when you malloc you free. Other than that, don't worry about it!

[_uj]

A vector (from the C++ standard library) is often better than an ordinary array. It has automatic memory management.

[TheCPUWizard]

...and in any case, no harm will ever occur to the memory of the computer, and in general even sloppy programs will not hold onto memory after the process completes... NOT advocating sloppy programming

[XeRoO]

...and in any case, no harm will ever occur to the memory of the computer, and in general even sloppy programs will not hold onto memory after the process completes... NOT advocating sloppy programming

unless you could use up all the free mem... but that would have to be one big program...

[TheCPUWizard]

Actually a run-away can easily exhaust the entire 2GB address space for the process. Depending on virtual memory limits, this may have a fatal impact on the execution of other processes, but still no harm will come to the memory