[PATCH v3 6/7] buildtools/chkincs: use a staging directory for headers

[Bruce Richardson]

On Thu, Sep 25, 2025 at 10:42:47AM +0200, David Marchand wrote:
> Hello Bruce,
> 
> On Thu, 25 Sept 2025 at 10:00, Bruce Richardson
> <bruce.richardson at intel.com> wrote:
> >
> > On Wed, Sep 24, 2025 at 07:25:34PM +0200, David Marchand wrote:
> > > A problem with the current headers check is that it relies on
> > > meson dependencies objects that come with their include_directories
> > > directives, and all of those point at the library / driver sources.
> > >
> > > This means that we won't detect a public header including a private
> > > (as in, not exported) header, or a driver only header.
> > >
> > > To address this issue, a staging directory is added and every header
> > > is copied to it.
> > >
> > > Drivers and library headers are staged to two different directories
> > > and the check is updated accordingly.
> > >
> > > Signed-off-by: David Marchand <david.marchand at redhat.com>
> >
> > In general looks ok to me.
> > One small comment though - can we not have "staging" as a top-level
> > directory, but instead hide it inside the buildtools directory, or even the
> > chkincs directory? I dislike having too many subdirectories directly off
> > the root of the project, especially ones purely for internal tooling.
> 
> Well, at first I was trying to change the whole build process iow rely
> only on the staging directory and remove all the include_directories:
> directives from the declare_dependency() objects.
> Libraries and apps were ok, but there were a *lot* of complications
> with drivers (what a *huge mess*, especially for NXP drivers with
> "compat.h" includes, and Marvell drivers to a smaller extent).
> I may retry in the future with some AI tool that will brute force this :-).
> 
> For now, I gave up but did not reconsider the location of the staging part.
> Moving to buildtools is indeed saner as it is only for the check now,
> and I can also make this staging stuff dependent on the check_includes
> option now.
>

I wonder should we just consider making chkincs an install-time job rather
than a build-time one? We could look to build chkincs using a custom
install script (meson.add_install_script) after the header copies are
already done for us. That should cut down on the complexity within the
build system, but it does mean an additional install step to a temporary
directory to get it to run. However, for use in our CI I don't see why
having an install step with DEST_DIR set to /tmp shouldn't be feasible.

/Bruce