Understanding of C programming syntax [duplicate]

Question

i came across this syntax and i am not able to know how to start understanding this.

How to start decoding of such piece of c programming code.

(*(void(*)())0)();

i have tried to compile this code and it compile without any warning or error. SO it seems valid syntax of c programming.

Answer 1

Break it as follows:

• (void(*)()) represents a cast of 0. Here its is a pointer to a function with return type void and can have any number of arguments.

     (  void  (*)  ( )  )
         ^     ^    ^
         |     |    |
         |     |    |
         |     |    |
         |     |    |
         +     |    +
  Return type  |    Function
               |
            Pointer
  

• *(void(*)())0 is dereferencing the address 0x00000000. I think its a function address there.

• (*(void(*)())0)(); call the function.