C syntax: Difference between revisions

This ensures that further attempts to dereference the pointer, on most systems, will crash the program. If this is not done, the variable becomes a [[dangling pointer]] which can lead to a use-after-free bug. However, if the pointer is a local variable, setting it to {{code|NULL}} does not prevent the program from using other copies of the pointer. Local use-after-free bugs are usually easy for [[static analyzer]]s to recognize. Therefore, this approach is less useful for local pointers and it is more often used with pointers stored in long-living structs. In general though, setting pointers to {{code|NULL}} is good practice {{according to whom|date=August 2020}} as it allows a programmer isto {{code|NULL}}-check pointers prior to dereferencing, thus helping prevent crashes.