> I think that I should have Cc'ed the OP. Resending...
>
> On 2026-07-14 09:56:44 +0000, Alexy via Tinycc-devel wrote:
> > #include <stdio.h>
> >
> > int main()
> > {
> > char t[5][0];
> [...]
>
> This is a constraint violation:
>
> In ISO C99, 6.7.5.2 Array declarators:
>
> [...] If they delimit an expression (which specifies the size of an
> array), the expression shall have an integer type. If the expression
> is a constant expression, it shall have a value greater than zero.
> [...]
>
> So this is just a missing diagnostic, not a serious bug!
>
One nuance: TCC intentionally accepts zero length arrays as a GNU
extension. The real gap is that TCC has no effective strict/pedantic
mode in which the required ISO diagnostic is emitted.
After accepting the extension, every inner array access is undefined.
t[5] additionally exceeds the outer array. A zero row size also
explains why different rows may map to the same address.
A warning or pedantic mode enhancement would be appropriate. Rejecting
[0] unconditionally would break GNU compatibility.
Mounir IDRASSI
_______________________________________________
Tinycc-devel mailing list
[email protected]
https://lists.nongnu.org/mailman/listinfo/tinycc-devel
