The sad thing is---there are processors that can do that. The MIPS can trap on overflow (the ADD instruction will do that) but C compilers tend to use the non-

The sad thing is---there are processors that can do that. The MIPS can trap on overflow (the ADD instruction will do that) but C compilers tend to use the non-trapping versions of said instructions (ADDU---add unsigned). The VAX architecture (to go back some thirty-five years) can trap or not---there's a bit in the flags register that controls overflow traps. On the x86 line, you can trap on overflow, but the check has to happen after each instruction. The obvious method (using INTO) is slow (http://boston.conman.org/2015/09/05.2 http://boston.conman.org/2015/09/05.2) while using a conditional jump (JO) doesn't incur much overhead (http://boston.conman.org/2015/09/07.1 http://boston.conman.org/2015/09/07.1) but it does lead to overall slower code because you have to use instructions that set the overflow flag. LEA (can be used to add and multiply) never sets the overflow flag, so instead of using a single instruction to, say, multiply by 16 and add 7, you have to use multiple instructions.