[vql]

Quote:

#include <stdio.h>
class A {
public:
void PrintMe();
};

void A::PrintMe()
{
printf("Hello World\n");
}

void main()
{
A* p = 0;
p->PrintMe(); // why not crash
}

Please explain why the program is not crash when access to function PrintMe of object NULL. Please explain me clearly. Thanks.

[shabbir]

Because you compiler does find that function where p points.

[DaWei]

Because your compiler is not standards compliant (neither is MS) in this respect.

Your use of the return type, "void", for main is also non-compliant.

[vql]

Quote:

Originally Posted by shabbir

Because you compiler does find that function where p points.

I think you are wrong because p is NULL pointer. The function also have a address, where p points to. But compiler can not know p's address -> so compiler also don't know the function's address.

[shabbir]

Quote:

Originally Posted by vql

I think you are wrong because p is NULL pointer. The function also have a address, where p points to. But compiler can not know p's address -> so compiler also don't know the function's address.

If you are using MS compiler try using an F11 at the function call and see what happens