@addWithOverflow is easy to implement in C, but you still need to look at the assembler code to see if the compiler did the right thing. I don't like that tens

@addWithOverflow is easy to implement in C, but you still need to look at the assembler code to see if the compiler did the right thing. I don't like that tension between C code you've arranged in just the right way and hoping that it continues to generate the assembler output it did once. I guess a portable set of compiler intrinsics it what is really needed to solve this problem. There is an x86 intrinsic for 32 x 32 -> 64 bit multiply now-a-days https://docs.microsoft.com/en-us/cpp/intrinsics/emul-emulu?view=msvc-160 https://docs.microsoft.com/en-us/cpp/intrinsics/emul-emulu?v... And one for 32 + 32 -> 32 + carry also. Though I don't know how portable __emulu is.. does it work on ARM for instance?