Dereferencing a pointer to 0 in C

Question

Sometimes data at memory address 0x0 is quite valuable -- take x86 real mode IVT as a more known example: it starts at 0x0 and contains pointers to interrupt handlers: a dwo

Answer 1

How do people actually use 0x0 when it's needed?

By either:

• writing the required code in assembly language, or
• writing the code in C and verifying that their compiler generates correct assembly language for the desired operation