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0 pointsJoker_vD6d ago0 comments

Ah, INT_MIN. If I had a nickel every time I saw an implementation of inttostr/strtoint that don't properly handle it, I'd probably have about $5. So I too thought about possibility of it serving as a NaN of signed integers... but I doubt we'll see it any time soon.

Also, apparently, shifting a negative number to the left is UB in C.

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Dylan168076d ago· 2 in thread

Left shifting a large positive number is also UB. C made a lot of things undefined that would make much more sense as implementation defined.

Joker_vDOP6d ago

Yep. Basically, if you take a signed int/long/etc. and a set bit shifts left into the sign bit — UB.

> a lot of things... would make much more sense as implementation defined.

Or even just defined. Apparently, the fact that shifting right a signed number is done arithmetically, not logically, is implementation-defined too.

Well, at lest bitwise not/and/or are (almost) fully defined even for signed integers, so that's something.

Dylan168075d ago

Well at the time it made sense not to force two's complement. But I would try harder to trim the UB list over time.

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