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Mixing delete and delete[]

Mixing delete and delete[]

Question:
I am programming with Visual C++ 5.0 and the class library StarView from StarDivision.Looking at the Source from StarView, I found bad code:

void** p = new (void*)[100];...delete p; <-- wrong operator, should be delete[] instead

Could this be the reason for the following warnings during program execution in debug mode:

Could not free object from heap using pointer xyz.

Can the library handle this problem and free the objects correctly?

Answer:
Probably not.

You are correct that arrays allocated using new should normally use the delete [] syntax. However, it is not always necessary to use this syntax.

The delete operator signifies that you are freeing the memory for one or more objects. But C++ does more than just release the memory. It also calls the destructors for objects you are deleting. If you have an array of class objects, then C++ will call the destructor for each object in the array. This is why the delete [] syntax is used. It tells C++ that it must destroy all the objects in the array.

However, many objects, such as char and void* have no destructors. For data types such as these, it really doesn't make any difference if you use delete or delete [].

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