


Why Does Calling a Class Method Through a NULL Pointer Sometimes Seem to Work in C ?
Calling Class Methods Through NULL Class Pointers: An Undefined Behavior
The provided code snippet raises the question of calling class methods through a NULL class pointer. The code includes a class named ABC with a member function and a main function that attempts to access the class method using a NULL pointer.
Contrary to expectations, the code executes successfully without any apparent issues. This can be explained by the concept of undefined behavior in C .
When invoking a member function via a NULL class pointer, the behavior is deemed undefined. This means that an arbitrary action could occur, ranging from normal execution to unexpected crashes.
However, in this specific instance, the apparent functionality stems from the fact that the print method does not utilize the this pointer, which refers to the object being operated on. This allows the function to execute without explicit reliance on an instantiated object.
Hence, it is vital to emphasize that accessing member functions through NULL class pointers is highly discouraged, as the results are unpredictable and could lead to unexpected consequences.
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