[ovs-dev] [PATCH v4 1/1] acinclude: Also use LIBS from dpkg pkg-config

[Ben Pfaff]

On Mon, Feb 11, 2019 at 11:37:25AM +0100, Christian Ehrhardt wrote:
> On Mon, Feb 11, 2019 at 11:06 AM Luca Boccassi <bluca at debian.org> wrote:
> >
> > On Mon, 2019-02-11 at 07:59 +0100, Christian Ehrhardt wrote:
> > > On Sun, Feb 10, 2019 at 5:53 PM Ben Pfaff <blp at ovn.org> wrote:
> > > >
> > > > On Thu, Feb 07, 2019 at 12:46:40PM +0100, Christian Ehrhardt wrote:
> > > > > DPDK 18.11 builds using the more modern meson build system no
> > > > > more
> > > > > provide the -ldpdk linker script. Instead it is expected to use
> > > > > pkgconfig for linker options as well.
> > > > >
> > > > > This change will set DPDK_LIB from pkg-config (if pkg-config was
> > > > > available) and since that already carries the whole-archive flags
> > > > > around the PMDs skips the further wrapping in more whole-archive
> > > > > if that is already part of DPDK_LIB.
> > > > >
> > > > > To work reliable in all environments this needs pkg-config
> > > > > 0.29.1.
> > > > > We want to be able to use PKG_CHECK_MODULES_STATIC which
> > > > > is not yet available in 0.24. Therefore update pkg.m4
> > > > > to pkg-config 0.29.1.
> > > > >
> > > > > This should be backport-safe as these macro files are all
> > > > > versioned.
> > > > > autoconf is smart enough to check the version if you have it
> > > > > locally,
> > > > > and if the system's is higher, it will use that one instead.
> > > > >
> > > > > Finally make configure.ac use the locally provided pkg.m4 before
> > > > > calling the PKG_PROG_PKG_CONFIG macro.
> > > > >
> > > > > Signed-off-by: Christian Ehrhardt <christian.ehrhardt at canonical.c
> > > > > om>
> > > >
> > > > The explicit m4_include([m4/pkg.m4]) should not be
> > > > necessary.  aclocal
> > > > should pick it up automatically.
> > >
> > > Thanks Ben for the hint.
> > > I agree that it might pick it up automatically, but I have learned
> > > not
> > > rely on too much with autotools :-/
> > > @Luca - to add the explicit include was your suggestion from Friday
> > > the 25th, do you see a potential issue if we don't?
> >
> > Yes it should work without - but only one way to be sure :-)
> 
> yeah - "should (tm)" :-)
> 
> @Ben Pfaff - it surely works with the include and I see now drawback :-)
> If you want me I can send a V5 which drops the explicit include, but
> without being called to do so I'd lean towards keeping it explicit to
> be sure.
> Let me know what you prefer.

We rely on aclocal for other .m4 files so I see no reason not to rely on
it here too.