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Subject: Re: [RFC] roundup.3: New page documenting roundup(3) (was: bug in
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To: Alejandro Colomar <alx.manpages@gmail.com>,
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On 1/17/23 12:24, Alejandro Colomar wrote:
>=20
>  =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 This=C2=A0 macro=C2=A0 produces=C2=
=A0 incorrect values when x + step would=20
> overflow or
>  =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 wrap around

The macro can have undefined behavior on overflow, if the result type is=20
signed. So I suggest replacing "produces incorrect values" with "has=20
undefined behavior".

I suppose you could also document that the behavior is well-defined if=20
the result type is unsigned, but that sounds like overkill.