Meson build

[Pavel Hrdina]

On Tue, Sep 01, 2020 at 03:13:39PM +0200, Ján Tomko wrote:
> On a Tuesday in 2020, Pavel Hrdina wrote:
> > On Sun, Aug 30, 2020 at 02:34:56AM +0200, Toolybird wrote:
> > > Hi,
> > > 
> > > Just a heads up on my experiences with the new build system.
> > > 
> > > Arch Linux
> > > meson-0.55.1
> > > 
> > > Overall, it looks good, so well done!
> > > 
> > > Just a couple of minor things I noted:
> > > 
> > > 1. Arch uses a meson wrapper script (arch-meson) that sets:
> > > 
> > >   --buildtype plain
> > > 
> > > This seems to trigger a bug in meson that results in copious bogus compiler warnings:
> > > 
> > > cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
> > > cc1: warning: ‘-Wformat-extra-args’ ignored without ‘-Wformat’ [-Wformat-extra-args]
> > > cc1: warning: ‘-Wformat-zero-length’ ignored without ‘-Wformat’ [-Wformat-zero-length]
> > > cc1: warning: ‘-Wformat-contains-nul’ ignored without ‘-Wformat’ [-Wformat-contains-nul]
> > > cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
> > > 
> > > which of course breaks -Werror builds.
> > > 
> > > I can easily work around it by setting `-D git_werror=disabled' or even better still:
> > > 
> > > CFLAGS+=" -Wall" arch-meson...
> > 
> > This should be easily fixable by adding -Wformat in our list of flags
> > that we pass to compiler. We were incorrectly relying on meson to add
> > -Wformat automatically and since we add the other -Wformat* flags
> > manually we should add -Wformat as well. I'll post a patch to fix this.
> > 
> 
> What would that fix?
> 
> It would neither be a plain build, nor a full -Werror build (since we're
> missing -Wall).

It would fix building libvirt from git in case user uses
buildtype=plain.

> > > Maybe this github issue is related?:
> > > 
> > > https://github.com/mesonbuild/meson/issues/7399
> > > 
> > > 2. Arch currently builds libvirt with support for ZFS. Seeing as ZFS is not in the distro proper, a simple Autoconf tweak is used:
> > > 
> > > ZFS=/usr/bin/zfs ZPOOL=/usr/bin/zpool \
> > > ./configure ...
> > > 
> > > This is surprisingly hard to emulate with meson, in fact it appears impossible, unless I resort to dodgy hacks with sed etc.
> > 
> > I'm not sure I understand the reasoning behind this.
> > 
> > For normal usage users of libvirt should not fake that something exists
> > to make libvirt building the support for it because obviously it will
> > not work.
> > 
> > If you are asking from packager POV you should add ZFS as regular build
> > dependency and also run dependency.
> > 
> 
> If it's possible to fake it, it's not a build dependency.
> 
> Jano
> 
> > I'm looking into the arch linux packaging and if that's your concern I
> > guess you should create libvirt-storage-zfs sub-package like it is done
> > for gluster, iscsi-direct and rbd.
> > 
> > Pavel
> 
> 


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://listman.redhat.com/archives/libvirt-users/attachments/20200901/13f9c68c/attachment.sig>