[Buildroot] [PATCH] libselinux: set PREFIX to generate proper .pc file
Marcus Folkesson
marcus.folkesson at gmail.com
Sun Jan 7 16:51:32 UTC 2018
Hi Thomas,
On Sun, Jan 07, 2018 at 05:34:27PM +0100, Thomas Petazzoni wrote:
> Hello,
>
> On Sun, 7 Jan 2018 17:24:34 +0100, Marcus Folkesson wrote:
>
> > > How can this work without passing PREFIX=/usr also at install time ?
> > > (Same question for libsemanage and libsepol).
> >
> > If not PREFIX is passed, it get the value of $(DESTDIR)/usr, which I
> > think is correct?
>
> No, in the standard semantic of DESTDIR and PREFIX:
>
> - PREFIX should be /usr, and DESTDIR $(TARGET_DIR) or $(STAGING_DIR)
> for target installation
>
> - PREFIX should be $(HOST_DIR) for host installation, DESTDIR is not
> used
>
> PREFIX is where the software is going to be executed from. So the
> software is going to be executed from /usr for target software, from
> $(HOST_DIR) for host software. PREFIX potentially has an effect on the
> stuff being built: PREFIX might end up being hardcoded into the
> binaries being compiled.
>
> DESTDIR is used to divert the installation. It is only meaningful
> during installation. It has no effect on the stuff being built: DESTDIR
> is never going to be hardcoded in a binary.
>
You are right.
> > If PREFIX=/usr at install time, it tries to install on the host
> > system.
>
> That's bogus.
Just to make clear - *this* package will try to install on the host
system.
>
> > I guess autotools would have done a better job with DESTDIR and PREFIX.
>
> Yes.
>
> > What I can tell, the libselinux.pc is the only target that make use of
> > PREFIX during compile time.
> >
> > But maybe I should set PREFIX explicitly to $(XXXXX_DIR)/usr during
> > installation just for clarity?
>
> In the standard (autotools) semantic of PREFIX,
> PREFIX=$(TARGET_DIR)/usr is wrong, see above.
>
> > From libselinux/src/Makefile:
> > PREFIX ?= $(DESTDIR)/usr
>
> Yes that's just plain wrong.
>
> So, two options:
>
> - We fix libselinux Makefile to have a more standard DESTDIR/PREFIX
> usage.
I think we should go for this one in the long run.
I will try to come up with something and get it upstreams for the
selinux project.
Should we keep libselinux Makefile as-is in meanwhile or add patches?
I can take responsibility for the packages being fixed when it is
upstreams.
>
> - We keep libselinux Makefile as-is, but we had some comments in
> libselinux.mk that explain the weird PREFIX/DESTDIR usage.
>
> Thanks!
>
> Thomas
> --
> Thomas Petazzoni, CTO, Free Electrons
> Embedded Linux and Kernel engineering
> http://free-electrons.com
Best regards
Marcus Folkesson
More information about the buildroot
mailing list