You are basically arguing CF == !CF. On MIPS you literally have to compare your result with an operand in order to establish if there was an overflow. On Arm yo

You are basically arguing CF == !CF. On MIPS you literally have to compare your result with an operand in order to establish if there was an overflow. On Arm you just look at the status register. When I was doing embedded development, I used C as portable assembly in practice and I know I wasn't the only one. Can you do everything an architecture enables you in a portable way? No, of course not.