How to do "Set Next Statement" or "Set Instruction Pointer" in GDB[]
This is actually quite simple! a quick look into the manual gave me the answer.
Constraint: It's disallowed to jump between functions, as the stack frames are left unchanged.
Suppose you want to go to line #n, type these two commands in GDB and you're there:
tbreak n jump n
tbreak - so that debugger will be in "break" mode
jump - to actually change the PC.