OC-error prompt

EXC_BAD_ACCESS

Indicates that you send a message to an object that has been freed. Whenever your application tries to reference a corrupted pointer, an exception is thrown by the kernel

The essence of EXC_BAD_ACCESS

EXC is an exception.BAD ACCESS means that the application cannot access the memory area, that is, the area you want to access has been released

Zombie Mode

Hook the address Sanitizer
object to be releasedIt is a zombie object
The pointer to the zombie object is a wild pointer, and sending a message to a wild pointer will EXC_BAD_ACCESS
A null pointer means that the pointer is nil. Sending a message to a null pointer will not respond.