bug#22186: Use {C,CPLUS,OBJC}_INCLUDE_PATH instead of CPATH

[ludo@gnu.org (Ludovic Courtès)]

Andy Wingo <wingo@igalia.com> skribis:

> On Thu 17 Dec 2015 22:43, ludo@gnu.org (Ludovic Courtès) writes:
>
>> Andy Wingo <wingo@igalia.com> skribis:
>>
>>> We should be using C_INCLUDE_PATH instead of CPATH, to mark system
>>> headers as system headers.  Except that C_INCLUDE_PATH only works for
>>> C, so we need to also set CPLUS_INCLUDE_PATH and OBJC_INCLUDE_PATH.
>>> And that's the proposal of this bug :)
>>
>> The intent of this “system header” classification, AIUI, is to not
>> bother users with issues in libc headers.
>
> I don't think this is true, for what it's worth :)  If we take FHS
> systems to be the de-facto default standard on how things should behave,
> -isystem covers all of /usr/include, so in practice it covers not just
> libc warnings, but many other warnings, which when you pass -Werror
> would then become errors.

Now that you mention it, it makes a lot of sense to me; I must have
lived away from FHS for too long now.  ;-)

We’re right on time to make the change you propose in ‘core-updates’.
I’ll give it a try and we’ll see how it goes.

Thanks for bearing with me!

Ludo’.