Question

Inside my template function I have the following code:

TypeName myFunction()
{

    TypeName result;
    void * storage = malloc( sizeof( TypeName ) );

    /*Magic code that stores a value in the space pointed to by storage*/

    result = *(TypeName *)storage;

    free( storage );
    return result;
}

This causes an “HEAP CORRUPTION DETECTED” error.If I don’t call the free() function, the error doesn’t occur, but I am afraid that I am creating a memory leak.what would be the proper way to return the value of “storage” and then deallocate the memory?

Answer 1

What about:

TypeName myFunction() {
    TypeName result;
    void* storage = &result;

    /*Magic code that stores a value in the space pointed to by storage*/

    return result;
}

Here, all your variables will be stored on the stack so you shouldn’t encounter heap-related problems (depending on what exactly your “magic” code does).

Is there a reason why you have your storage array separate from result? If the results will simply be copied into result, it would make more sense (IMHO) to only use one object (and either keep a void* pointer to it or type-cast &result as needed).

If there is a reason to use a separate storage and result, you will probably get better milage using TypeName storage = new TypeName and delete instead of malloc(4) and free.