Daniel Marjamäki <daniel.marjam...@gmail.com> writes:
> Do you have any opinion about adding a warning for:
>
> int f(char c)
> {
> return 10 * (c == 13) ? 1 : 2;
> }
>
> The multiplication has no effect. The function returns either 1 or 2.
>
> It would be interesting to know how a MELT script could look like for
> such a case.
The problem with warnings for this kind of code in C/C++ is that it
often arises in macro expansions. I think it would be necessary to
first develop a scheme which lets us determine whether code resulted
from a macro expansion or not, which I think would be quite useful in a
number of different cases.
> As far as I see the multiplication doesn't exist in the gimple format
> (looking at a.c.004t.gimple generated by -fdump-tree-all).
It gets constant folded in the front end.
Ian
