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		ryao 9 months ago \| parent \| context \| favorite \| on: Making memcpy(NULL, NULL, 0) well-defined Where does it say that? I thought this was a famous example from formal methods showing why something really simple could be wrong. It would be strange for the standard to say to ignore it. The behavior is also well defined in two’s complement. People just don’t like it.

plorkyeran 9 months ago [–]

https://busybox.net/~landley/c99-draft.html#7.20.6.1

"The abs, labs, and llabs functions compute the absolute value of an integer j. If the result cannot be represented, the behavior is undefined. (242)"

242 The absolute value of the most negative number cannot be represented in two's complement.

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