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0 pointskzrdude5d ago0 comments

My go-to example of "UB is everywhere" is this one:

    int increment(int x) {
        return x + 1;
    }

Which is UB for certain values of x.

0 comments

TBF that is the same as saying "signed overflow is UB".

kzrdudeOP4d ago

yes but it is a 'picture' that makes you think about it in a different way.

C23 removed the whole stuff about indeterminate value and trap representation. Underflow/overflow being silent or not is implementation defined.

Signed overflow is just undefined.

j / k navigate · click thread line to collapse

TBF that is the same as saying "signed overflow is UB".

kzrdudeOP4d ago

yes but it is a 'picture' that makes you think about it in a different way.

C23 removed the whole stuff about indeterminate value and trap representation. Underflow/overflow being silent or not is implementation defined.

Signed overflow is just undefined.

j / k navigate · click thread line to collapse