The vast majority of the time, the GCC community is a very civil, cooperative space. On the rare occasions that it isn't, it's helpful to have something to point to to remind people of our expectations. It's also good for newcomers to have something to refer to, for both how they are expected to conduct themselves and how they can expect to be treated.
More importantly, if there is offensive behavior that isn't addressed immediately, it's important for there to be a way to report that to the project leadership so that we can intervene.
The Guidelines are helpful for establishing the kind of behavior we want to see, but it's also important to have a reporting mechanism to help people feel safe and supported in the community, and to help leadership to hear about problems that might otherwise have escaped their notice.
Certainly, in many cases. And we hope referring to the CoC might be helpful then, as well. If the problem is successfully resolved, no report is necessary, though individuals might still want to let the CoC committee know about the incident just for their information.
The CoC committee will get their perspective, and any other available information, before taking any action.
Besides which, we expect the response to the vast majority of incidents to be email asking those involved to moderate their behavior. That has been the experience of other free software projects after adopting a code of conduct: see the Linux Kernel CoC reports for an example.
No, this is a code of conduct, not a code of philosophy. And it only deals with behavior within the context of the GCC project; for instance, harassment in private email in response to a public discussion is covered, a social media post about politics is not.
Yes. We may take no action if the issue seems to have been resolved, but it can be helpful to have context for future discussions.
Please also see the Reporting Guidelines and Response Guide. If they don't answer your question either, email conduct@gcc.gnu.org with any additional questions or feedback.