Re: [Qemu-devel] [PULL 0/4] Build system patches for 2019-07-02

[Peter Maydell]

On Wed, 3 Jul 2019 at 06:18, Markus Armbruster <address@hidden> wrote:
>
> Peter Maydell <address@hidden> writes:
> > This seems to break the incremental builds (most hosts):
> >
> > make: Entering directory '/home/petmay01/qemu-for-merges/build/w64'
> > make: *** No rule to make target 'subdir-slirp', needed by
> > 'config-host.h'.  Stop.
> > make: *** Waiting for unfinished jobs....
> > config-host.mak is out-of-date, running configure
> > Install prefix    c:/Program Files/QEMU
> > [rest of configure output snipped; no other output]
>
> PATCH 3 changes the dependency configure writes to config-host.h like
> this:
>
>      if [ "$slirp" = "git" -o "$slirp" = "internal" ]; then
>     -    echo "config-host.h: subdir-slirp" >> $config_host_mak
>     +    echo "config-host.h: slirp/all" >> $config_host_mak
>      fi
>
> For me, make complains, reruns configure (which adjusts the dependency),
> then happily makes everything.
>
> Hmm, I see.  Without -k, make stops after rerunning configure.
>
> Is that a problem?

Yes: most people don't run 'make -k'. We should strive to avoid
breaking incremental builds, I think they are the most common
way developers build QEMU.

thanks
-- PMM