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Yes, correct me if I'm wrong, but I thought the point was that 0x8000 is like negative zero and so of no utility, redundant. So let's make it useful.

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A couple of things that are special about 2s compliment

- There are no redundant numbers like -0

- Adding two integers together in this format works with negative and positive numbers with no special case.

-1 is actually 0xFF or 0xFFFF etc. So 0xFF + 0x01 (-1 + 1) "overflows" to 0.

It's not. 0x8000 is the smallest (-32,768) integer that can be represented with 16-bits and two's complement.

abs() of this value also happens to exceed the maximum positive value. Which means that in C, a simple negation can cause signed integer overflow -(-32768), and therefore UB.

Yeah, I think it is funny that in a standard binary, it would replace negative zero and makes some sense. In two's complement, it replaces the minimum value.

Fair that sentinel value is sentinel value, I suppose. But it is not like it is not a known and unique number in that encoding.

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