Goto a specific Address in C

c pointers assembly goto pointer-address
Rgarg picture Rgarg · Oct 4, 2013 · Viewed 9.3k times · Source

How can I JMP to a specific address in C?

I want to use 

goto 0x10080000

This is not working, is there other way I can change the address of Program Counter??

Answer

Alex picture Alex · Oct 4, 2013

You can cast the address to a function pointer and then jump into:

((void (*)(void))0x10008000)();

To make it a bit more clear:

typedef void (*func_t)(void);
...
((func_t)0x10008000)();

But this is a function, the compiler will emit a branch instruction that expect to return (then is up to you to make your function return or not). Also notice that the compiler will produce a code that expect to find a C function at the given address, about how the function arguments are given and returned.

If you need to emit a branch instruction without return you need to use inline assembly.

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