c - Why is this code able to access a null pointer without causing a crash? -


i have come across following piece of code, finds offset of member within structure. not able make out why not crash, though tries derefer null pointer

struct a_ {     int a;     int b; };  int main() {     int offset = &(((struct a_ *) 0x0)->b);     printf ("offset of b = %x\n", offset); }   output = 4

however not able make out why not crash, though tries derefer null pointer.

you forming invalid address undefined behavior there no dereference of null pointer because of & operator cancels dereference.


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