Re: [PATCH v06 18/36] uapi linux/errqueue.h: include linux/time.h in user space

From: Willem de Bruijn
Date: Sun Aug 06 2017 - 18:04:40 EST


On Sun, Aug 6, 2017 at 5:52 PM, Mikko Rapeli <mikko.rapeli@xxxxxx> wrote:
> On Sun, Aug 06, 2017 at 05:42:13PM -0400, Willem de Bruijn wrote:
>> On Sun, Aug 6, 2017 at 5:33 PM, Mikko Rapeli <mikko.rapeli@xxxxxx> wrote:
>> > On Sun, Aug 06, 2017 at 05:24:20PM -0400, Willem de Bruijn wrote:
>> >> >> > +#ifdef __KERNEL__
>> >> >> > +#include <linux/time.h>
>> >> >> > +#else
>> >> >> > +#include <time.h>
>> >> >> > +#endif /* __KERNEL__ */
>> >> >>
>> >> >> This will break applications that include <linux/time.h> manually.
>> >> >> I previously sent a patch to use libc-compat to make compilation succeed
>> >> >> when both are included in the case where <linux/time.h> is included after
>> >> >> <time.h>.
>> >> >>
>> >> >> https://lkml.org/lkml/2016/9/12/872
>> >> >>
>> >> >> The inverse will require changes to the libc header to avoid redefining
>> >> >> symbols already defined by <linux/time.h>
>> >> >>
>> >> >> The second patch in that 2-patch set included <linux/time.h>
>> >> >> unconditionally after the fix. This broke builds that also included
>> >> >> <time.h> in the wrong order. I did not resubmit the first patch as a
>> >> >> stand-alone, as it is not sufficient to avoid breakage.
>> >> >
>> >> > I wasn't aware of your change, but I was about to send this to fix the
>> >> > case when glibc <time.h> is included before <linux/time.h>:
>> >> >
>> >> > https://github.com/mcfrisk/linux/commit/f3952a27b8a21c6478d26e6246055383483f6a66
>> >>
>> >> There are a few differences between the two. Including <time.h> does not
>> >> unconditionally define all the symbols. Some are conditional on additional
>> >> state, such as __timespec_defined.
>> >
>> > Yep, your patch seems better for libc-compat.h. Could you send it again?
>>
>> Okay. Or feel free to include it in the patchset if that helps resolve
>> dependencies.
>
> If you don't have the time, I will send tomorrow a new version of this
> patch which fixes the commit topic and before that your libc-compat.h change
> so both could be applied together.

Please do. Thanks!