If I have a function that has a variable declared inside it (which is a pointer) that can be set equal to a pointer returned from another function, do i need to delete it before returning from the function?
Code:void test() { Test* t = obj.getTest(); ...elided... //do this? (assuming others need to use what's in get() ) delete t; t = NULL; }
That depends on the semantics of getTest(), namely, whether it transfers ownership. If it is giving you a pointer to data you don't "own," you certain should NOT delete it.Originally Posted by 6tr6tr
Depends on how the function is implemented, but generally no. It is common practice to have functions responsible for any data they allocate. In this case, the returned pointer is probably stored in obj, and will be deleted when that object is destroyed.
It is too clear and so it is hard to see.
A dunce once searched for fire with a lighted lantern.
Had he known what fire was,
He could have cooked his rice much sooner.
This
serves absolutely no purpose - the variable t will no longer exist after you return from the function (which is the very next thing that happens), so there's absolutely no meaning to setting the variable to NULL or any other value at this point.Code:t = NULL;
--
Mats
Compilers can produce warnings - make the compiler programmers happy: Use them!
Please don't PM me for help - and no, I don't do help over instant messengers.
But then again, it likely won't hurt because the compiler might just optimize it away. Even if it doesn't, it hardly takes CPU time, so it's not really harmful.
The best solution would, of course, be to use a smart pointer. Then there is probably no need to set NULL in the first place.
