Re: Do not use -Werror by default in your modules without joining #testable

[Emmanuele Bassi <ebassi gmail com>]

On 2 April 2017 at 16:44, Sébastien Wilmet <swilmet gnome org> wrote:
> On Sun, Apr 02, 2017 at 03:59:39PM +0100, Emmanuele Bassi wrote:
> > The point of my email was, though, that people should be keeping an
> > eye on their modules on the CD pipeline.
>
> It's easier to keep an eye on our local compilation output, and rebuild
> from time to time the dependencies in jhbuild.

Sure, it's "easier" for some people: out of sight, out of mind.

It's also broken, because it relies on humans to do the work of machines.

> GNOME Continuous is useful to detect as early as possible real build
> breakages (a FTBFS *with* --disable-Werror).

> Or determining the culprit
> commit when a unit test starts to fail (and possibly cross-modules, e.g.
> a commit in gtk that makes an app unit test to fail).

You seem to misunderstand what a continuous delivery/continuous
integration pipeline is for.

The whole point of CD/CI is to detect issues early, even before unit
testing fails. Compilation warnings are just a prelude to additional
issues down the line. Otherwise, why using them at all? You can build
with all the compilation warnings turned off already and not care at
all.

If you specifically enable compilation warnings, and then go to the
extra length of enabling -Werror by default, then it means you do care
about them. Caring about them, though, does not stop at the boundary
of your Git repository; that's why we have a continuous delivery
platform: to figure out the impact of changes between modules, and to
ensure that a whole set of modules builds correctly.

Disabling -Werror in Continuous would make *my* life easier — I
wouldn't have to file bugs or tag modules; it would also defeat the
point of having Continuous in the first place.

So, *please*: be proactive, and use the notifications from the
Continuous builder to know if your module is affected, instead of
waiting on a bug to be filed.

Ciao,
 Emmanuele.

-- 
https://www.bassi.io
[@] ebassi [@gmail.com]