Interpreting Memory Block Types
As seen in Enabling Memory Leak Detection, the memory leak information identifies each block of leaked memory as a normal block, a client block, or a CRT block. In practice, normal blocks and client blocks are the only types you are likely to see.
- A normal block is ordinary memory allocated by your program.
- A client block is a special type of memory block used by MFC programs for objects that require a destructor. The MFC new operation creates either a normal block or a client block, as appropriate for the object being created.
- A CRT block is a block of memory allocated by the CRT library for its own use. The CRT library handles the deallocation for these blocks, so it is unlikely you will see these in the memory leak report unless something is seriously wrong (for example, the CRT library is corrupted).
There are two block types you will never see in the memory leak information:
- A free block is a block of memory that has been released.
- An ignore block is a block that you have specifically marked so it doesn't appear in the memory leak report.