Re: Arithmetic expression: evaluation order bug

[Andreas Schwab]

On Dez 30 2022, Steffen Nurpmeso wrote:

> Andreas Schwab wrote in
>  <87358xambe.fsf@igel.home>:
>  |On Dez 29 2022, Alain D D Williams wrote:
>  |> On Thu, Dec 29, 2022 at 10:30:09PM +0100, Steffen Nurpmeso wrote:
>  |>
>  |>> only clang warns on sequencing when tested.
>  |>
>  |> Ah: so only clang gives the warning that the others should probably give.
>  |
>  |$ gcc -Wall t.c
>
> Sorry, that (-Wall) not.
>
>  |t.c: In function ‘main’:
>  |t.c:7:11: warning: operation on ‘i’ may be undefined [-Wsequence-point]
>  |         i += j += i += j;
>  |           ^~
>  |t.c:11:11: warning: operation on ‘i’ may be undefined [-Wsequence-point]
>  |         i += j += i += i;
>  |           ^~
>
> Luckily it is not in real life.

Luckily you are mistaken.

-- 
Andreas Schwab, schwab@linux-m68k.org
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