Re: [PATCH v2 5/5] gitlab-ci.d: Build with --enable-fdt=system by default

[Thomas Huth <thuth@redhat.com>]

On 23/02/2023 15.02, Daniel P. Berrangé wrote:
> On Tue, Feb 07, 2023 at 09:14:47PM +0100, Thomas Huth wrote:
>> By using --enable-fdt=system we can make sure that the configure
>> script does not try to check out the "dtc" submodule. This should
>> help to safe some precious CI minutes in the long run.
> 
> If our containers have the system dtc installed, I'm pretty
> surprised that configure is choosing to use dtc submodule.
> I thought we won't touch the submodule at all if system dtc
> was sufficiently new.
> 
> IOW, do we have a logic bug in configure making it incorrectly
> use dtc submodules ?

Yes, it sounds weird at the first glance, but it's really this way (look for 
the "Simpler to always update submodule, even if not needed" comment in the 
configure script): The problem is that the initial submodule handling is 
done in configure already, so you have to know the needed submodules there 
already. But the check for usability of libfdt is only done in meson.build, 
so you already need to have the submodule available there in case the 
system's libfdt is not usable.

It could maybe cleaned up somehow, but OTOH, I'm still hoping that we can 
rid of the dtc submodule in the near future, so it's maybe not worth the 
effort to spend too much time with this right now.

  Thomas