Returning Large Objects in Functions

Question

Compare the following two pieces of code, the first using a reference to a large object, and the second has the large object as the return value. The emphasis on a \"large o

Answer 1

Your first snippet is especially useful when you do things like have getObjData() implemented in one DLL, call it from another DLL, and the two DLLs are implemented in different languages or different versions of the compiler for the same language. The reason is because when they are compiled in different compilers they often use different heaps. You must allocate and deallocate memory from within the same heap, else you will corrupt memory.

But if you don't do something like that, I would normally simply return a pointer (or smart pointer) to memory your function allocates:

LargeObj* getObjData()
{
  LargeObj* ret = new LargeObj;
  ret->fillWithData() ;
  return ret;
}

...unless I have a specific reason not to.