Re: [avr-gcc-list] [Bug target/35634] New: [avr] result of char promotion comes out of CHAR_MIN/MAX

[Paulo Marques]

Dmitry K. wrote:
> [...]
> void foo (int i)
> {
>     static int n;
>     if (i < CHAR_MIN || i > CHAR_MAX)
>         abort ();
>     if (++n > 1000)
>         exit (0);
> }
>
> int main ()
> {
>     char c;
>     for (c = 0; ; c++) foo (c);
> }

Is this strictly wrong, from the C definition point of view?

I know that signed overflow is "undefined". How does this test case 
interacts with -fwrapv and -fno-strict-overflow?

For those unaware of signed overflow issues, there is a nice sum up here:

http://www.airs.com/blog/archives/120

I know that turning "undefined" into an "out of range" result is ugly, 
but so is signed overflow....

--
Paulo Marques
Software Development Department - Grupo PIE, S.A.
Phone: +351 252 290600, Fax: +351 252 290601
Web: www.grupopie.com

"...so she told me it was either her or the ham radio, over."