Re: [Tinycc-devel] bug?

[John Regehr]

Sorry, I mean it prints "-255".

I'm using tcc-0.9.24 on Ubnutu Linux.

John Regehr



John Regehr wrote:
> For the program below, tcc emits a program that prints "255" whereas 
> most compilers would say that the program should print "1".
>
> Of course wrapping the signed scalar p_99 has undefined behavior, so 
> what I am asking is: is tcc intentionally exploiting the undefinedness 
> of the program, or is this a bug?
>
> Thanks,
>
> John Regehr
>
>
>
> #include <stdio.h>
>
> int g_254;
>
> void func_97 (signed char p_99);
> void func_97 (signed char p_99)
> {
>   for (; p_99; p_99 -= 1)
>     g_254 = p_99;
> }
>
> int
> main (void)
> {
>   func_97 (-1);
>   printf ("%d\n", g_254);
>   return 0;
> }
>
>
> _______________________________________________
> Tinycc-devel mailing list
> address@hidden
> http://lists.nongnu.org/mailman/listinfo/tinycc-devel