Jeff Donner <jeffrey.donner@xxxxxxxxx> writes:
> How do you get no-ops to trigger a warning? Eg this:
>
> void noop()
> {
> int i = 6;
> i |= 0;
>
> int j = 5;
> j += 0;
>
> int k = 3;
> k = k;
> }
>
>> g++ -pedantic -Wall -Wextra -O3 -c noops.cpp
>>
>
> compiles without complaint. Am I just missing a flag? (4.1.x, 4.4.x, 4.6)
There is no general warning for no-ops. I'm not aware of any warning
for |= 0 nor for += 0 nor for self-assignment. The first two cases
don't seem common enough to warn about. Warnings are generally intended
to catch code which is likely a mistake. Is j |= 0 a likely mistake?
Hard to say, particularly if it is really
#ifndef O_BINARY
#define O_BINARY 0
#endif
i |= O_BINARY;
Ian
