On Mon, Mar 30, 2020 at 04:37:59PM +0200, Kevin Wolf wrote: > Am 30.03.2020 um 15:42 hat Daniel P. Berrangé geschrieben: > > On Mon, Mar 30, 2020 at 02:31:52PM +0100, Peter Maydell wrote: > > > On Mon, 30 Mar 2020 at 14:26, Markus Armbruster <arm...@redhat.com> wrote: > > > > > > > > Peter Maydell <peter.mayd...@linaro.org> writes: > > > > > > > > > AIUI from Paolo, the intention is to deprecate and eventually > > > > > stop supporting "in-tree" builds, so that the only option is > > > > > building in a separate build directory. I thought we should > > > > > probably mention that in the 5.0 changelog, so I wrote up some > > > > > text: > > > > > > > > > > https://wiki.qemu.org/ChangeLog/5.0#Build_Information > > > > > > > > Overdue. Thanks for doing this! > > > > > > > > > Suggestions for changes/comments etc welcome. > > > > > > > > Looks fine to me. > > > > > > Consensus in the thread seemed to lean towards having > > > the 'configure/make' runes auto-create a build directory; > > > if we want to do that we should probably not say anything in > > > the release notes, because we'll cause people to change > > > unnecessarily. Or at least have them say "We recommend > > > out-of-tree builds. In future we might make the commands > > > that currently do an in-tree build automatically create > > > and use a build directory for you." rather than a blanket > > > "we're going to drop this and you should change what you > > > do now". > > > > > > Thoughts? > > > > When the time comes to switch to Meson, we'll be forcing a > > separate build directory & that will also potentially involve > > a change in build instructions for users. > > > > So if we expect Meson will arrive in QEMU soon (say before end > > of this year), then I'd try to keep changes related to make to > > the bare minimum, and have Meson switch as the "flag day" when > > developers are forced to adapt their build process. > > > > IOW, merely warn people that in-tree builds are deprecated and > > not tested by the project and enourage switching to out of tree > > builds. Dont try to magically create a separate build dir now. > > If manually dealing with separate build directories is inconvenient > today, it will still be inconvenient with Meson, so this would mean > introducing the automatic directly creation together with the other > changes to enable Meson. Which is fine by me, as long as it is really > done when the external directory becomes mandatory, so that people won't > have to switch back and forth between directories.
>From packaging point of view if something has auto* files the default is IIRC to do in-tree build with most package managers. You have to adjust manually for out-of-tree build. I am not sure what is state of Meson support in packaging scripts across distributions. Most likely it will not be picked automagically so you have to provide a custom build script anyway. Then it is the time to look up the canonical build instructions. In other words dealing with Meson is inconvenient either way. Building in-tree or out-of-tree becomes a non-issue whan you switch to exotic build system anyway. That's not to say that auto* tools are great. It's just the replacements have issues that are not well understood by average Joe Packager while the auto* tools have good old issues people know how to deal with. Thanks Michal
