Re: [Qemu-devel] [PATCH v4] cutils: Provide strchrnul

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Peter Maydell (peter.maydell@linaro.org) wrote:
> On 11 June 2018 at 08:56, Markus Armbruster <armbru@redhat.com> wrote:
> > You're not printing $strchrnul like we print other configuration
> > results.  Hmm, we're not printing several of them.  Question for
> > maintainers (MAINTAINERS doesn't have any, so I'm cc'ing the top three
> > coughed up by get_maintainer.pl): bug or feature?  If feature, how do we
> > decide what to print?
> 
> If we printed everything that we tested for then the output would
> be unhelpfully enormous. My view is that we should print the
> "interesting" things for the user, ie the higher-level things
> that the user could potentially turn on by installing more
> libraries or has turned off explicitly or whatever. Reporting
> whether the host OS has strchrnul or whether we've had to
> provide our own implementation is doubly uninteresting:
>  * there's nothing the user could do to change this
>  * there is no visible effect (missing features, worse performance)
> 
> There's an argument that we should also log every config check
> result somehow (I think autoconf configures do this), but I
> don't think that our 'print stuff to stdout' is the right place
> for that.

We're not completely consistent, but I agree that we shouldn't print
the tiny things:

We're printing things that:
   a) Are user visible (e.g. KVM support)
   b) Reasonably major choices we make (e.g. coroutine backend)
   c) Some lesser things (madvise/posix_madvise/posix_memalign)
     However even (c) could be a problem if none were found

We probably shouldn't bother with printing things that have
no impact to either the user, or someone trying to cofnigure it and
wondering why a feature is missing.

Dave



> thanks
> -- PMM
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK