A pointer passed to a de-allocation (or re-allocation) function is checked to be valid; it should be previously returned by a corresponding (re-)allocation function and not have been de-allocated before. Table 1. shows the relationships between allocation and de-allocation functions.
Table 1. De-allocation functions and their corresponding allocation functions
| De- or re-allocation function |
Allocation function |
delete |
new |
delete [] |
new [] |
free() |
malloc(), calloc() or realloc() |
realloc() |
malloc(), calloc() or realloc() |
The application will terminate with an informative message and a core dump when a pointer is de-allocated that was not previously allocated with the corresponding allocation function.Note: When libcwd was configured with
–disable-magic then the check whether or not the de-allocated memory block was allocated with the corresponding allocation function is
not performed when the memory block is
invisible. The reason for this is that invisible memory blocks are simply not stored in the internal data structure: No information is known about them.
