CODEWITHSUNDEEP
c++pointers
Mr. Fahrenheit
Mr. Fahrenheit

Reputation: 35

Do I need to call delete to a pointer assigned to another pointer?

Say I have this:

char* data = new char[3];
char* tmp = data;
data = new char[3];

after that should I call delete for both pointers like so:

delete[] data;
delete[] tmp;

or is it just for data:

delete[] data;

I tried the first way but it gave me a heap error, the second way didn't cause me any problems, but then what happens to the memory tmp is pointing to, would there be a memory leak there?.

Upvotes: 0

Views: 58

Answers (1)

Abhijit
Abhijit

Reputation: 63777

It is important to understand that the delete operator releases any memory that was allocated by a previous new. So depending upon, the occurrence of new, the call to delete for the same allocated memory should match.

In your case, there are two invocation to new, new char[3] assigned to data which was further assigned to tmp. At this point, both tmp and data refers (points) to the same memory location on the heap. A second invocation of new , new char[3] further allocates memory equivalent to 3 character storage and assigns it to data. Thus it would make sense, to call delete twice on both the allocated blocks, refereed individually by tmp and data.

Upvotes: 2

Related Questions