On 16 November 2017 at 22:54, Antoine Pitrou <antoine@python.org> wrote:

Hi Victor,

Thanks for the answer!

Le 16/11/2017 à 13:48, Victor Stinner a écrit :
>
> faulthandler has a negligible cost on performance/memory.
>
> For -W default, I guess that your question is the cost on emitting a
> warning: overhead when a warning is displayed, and overhead when the
> warning is filtered. Right?

-Wdefault means -Wonce or -Walways? If the former, I don't expect many
warnings to be emitted.

Confusingly, neither of these: default, once, module, and always are all different settings.

once: once per process (regardless of location)

module: once per module (regardless of line)

default: once per location (line+module combination)

always: every time

Still, even with once-per-location behaviour, the warning overhead should be minimal.

Cheers,

Nick.