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Re: warning: operation on 'zero' may be undefined
Paul Brook wrote:
>> foo.cxx: In function `int main()':
>> foo.cxx:4: warning: operation on 'zero' may be undefined
>>
>> What does this mean ?
>
> You incrementing and assigning to the same variable in one statement,
> which invokes undefined behaviour.
>
> The code you wrote can be interpreted as
> zero = zero%3;
> or
> zero = (zero % 3) + 1
> or possibly even something entirely different.
The error message could use a clarification though.
Giovanni Bajo