Re: What is your opinion about unsigned int u = -2 ?

On 8/11/24 4:08 PM, Vir Campestris wrote:

On 11/08/2024 20:33, Tim Rentsch wrote:

Ick.  That choice is exactly backwards IMO.  Converting -1 to
an unsigned type always sets all the bits.  Converting -1u to
an unsigned type can easily do the wrong thing, depending
on the target type.

 "Converting -1 to an unsigned type always sets all the bits"
 In any normal twos complement architecture that's the case. But there are a few oddballs out there where -1 is +1, except that the dedicated sign bit is set.
 Andy

But, when that -1 value is converted to an unsigned type, that VALUE will be adjusted modulo the appropriate power of two.
signed to unsigned conversion works on VALUE, not bit pattern, so is invariant with the representation of the negative values.
Yes, in a union with a signed and unsigned, the type punning will let you see the representation of the types, but assignment works on values.