Run unit tests with C++ too

[Bruce Richardson]

On Wed, May 01, 2024 at 10:10:57AM +0100, Ferruh Yigit wrote:
> On 4/30/2024 9:57 PM, Patrick Robb wrote:
> > 
> > 
> > On Tue, Apr 30, 2024 at 4:13 PM Mattias Rönnblom <hofors at lysator.liu.se
> > <mailto:hofors at lysator.liu.se>> wrote:
> > 
> >     On 2024-04-30 15:52, Patrick Robb wrote:
> >     >
> >     >
> >     > On Sun, Apr 28, 2024 at 3:46 AM Mattias Rönnblom
> >     <hofors at lysator.liu.se <mailto:hofors at lysator.liu.se>
> >     > <mailto:hofors at lysator.liu.se <mailto:hofors at lysator.liu.se>>>
> >     > wrote:
> >     >
> >     >     It would be great if the unit test suite (app/test/*) was
> >     compiled (and
> >     >     run) using a C++ (C++11) compiler as well. At least, if such
> >     >is      available.
> >     >
> >     >
> >     > Sure, the UNH Lab can try this.
> >     >
> >     >
> >     >     With the current state of affairs, header file macros or
> >     functions are
> >     >     not verified to be functional (or even valid) C++.
> >     >
> >     >     "C is a subset of C++", which was never true, is becoming
> >     >less and      less so.
> >     >
> >     >     If all unit tests aren't valid C++, maybe one could start
> >     >with
> >     an "opt
> >     >     in" model.
> >     >
> >     >
> >     > Okay, so basically run the fast-test suite, record all that don't
> >     pass,
> >     > submit a bugzilla ticket stating which unit tests are not valid
> >     > on a certain c++ compiler, then bring CI Testing online using the
> >     > valid subset of fast-tests. This should work.
> >     >
> > 
> >     Sounds good.
> > 
> >     Just to be clear: the above includes extending the DPDK build
> >     system to build the app/test/dpdk-test binary in two versions: one
> >     C and one C++, so that anyone can run the C++ tests locally as
> >     well. Correct?
> > 
> > 
> > Okay, so now I am understanding this is not yet available. When I
> > responded this morning I was figuring that c++ compiler support was
> > available and I simply wasn't aware, and that we could quite easily set
> > cc={some c++ compiler}, meson would pick it up, and we would be able to
> > build DPDK and then run unit tests in this manner in CI testing. 
> > 
> > I didn't mean to suggest we would submit patches extending the build
> > system to this end. That's probably a little out of scope for what we
> > try to accomplish at the Community Lab. 
> > 
> > But if the aforementioned build system support is added, of course we
> > are willing to add that as a build environment for unit tests and
> > report those respective results.   
> 
> Does it have to be 'app/test/dpdk-test', why not build examples with C++?
> 
> Examples source codes can be installed with existing build support.
> Later we can build these examples with C++, this doesn't require any
> update in build system.
>
Reading through the history, I believe the ask here is to have the headers
validated for C++ compatibility. We previously added support to "chkincs"
for this - we can build chkincs-cpp with g++ as well as a regular
C-compiled chkincs binary.

/Bruce