+++ Johannes Schauer [2015-09-16 23:10 +0200]: > Hi, > > I'm really not the best person to answer your questions but since nobody else > replied yet, I'm gonna go ahead anyways.
You did a pretty good job of answering :-) > Quoting nice sw123 (2015-09-16 10:29:22) > > does the method of crosscompiling as described here > > https://wiki.debian.org/CrossCompiling work for all deb source packages ?? > > no. Nor will this be the case in the foreseeable future. Quite a lot of them could be made to eventually, but it's a massive job. > Some source packages happen to cross compile after you installed the right > cross compiler and then by doing: > > dpkg-buildpackage -aarmhf > > but this is certainly the minority. Right, although it's a non-trivial minority now. Many more could be made to work at this level with relatively small amounts of work. > > I've tried (under stretch) to build the mosquitto (MQTT) broker > > apt-get source mosquitto > > cd mosquitto* > > sbuild --host=armhf -d stretch-amd64-sbuild > > > After solving initial problems (had to install qemu in the schroot, so that > > python2.7-minimal:armhf can be configured)... > > You discovered yet another common problem. Installing qemu should not be > required for proper cross compilation. Instead you probably want > python2.7-minimal for your *build* architecture instead for armhf as it is > probably just used to run some Python scripts. This might mean that mosquitto > needs to build-depend on python with the :native qualifier. But since all of > this is really new, even how to do this properly has not yet fully been > figured > out yet. Right qemu is the wrong fix (although it may be expedient for other reasons). you want python:amd64 not python:armhf (And josch, this isn't really new - we've been working on it for 5 years now - it's just not finished yet: these things take _ages_ if you do them properly:-) OK, so you can get this working better if you do: apt-get install --no-install-recommends crossbuild-essential-armhf python-all debhelper apt-get install --no-install-recommends libssl-dev:armhf libc-ares-dev:armhf libwebsockets-dev:armhf libwrap0-dev:armhf uthash-dev:armhf uuid-dev:armhf to work round the wrong-arch python issue. Then dpkg-buildpackage -aarmhf -d (actually the -d isn't needed in this case but it usually is if apt-get build-dep -a$arch didn't 'just work') However as you've already found this fails to search /usr/include/arm-linux-gnueabihf for openssl/opensslconf.h That seems like a genuine problem. It might be the cross-toolchain (the gcc5 one is very new). I'll investigate a bit further. > > I've also seen http://people.linaro.org/~wookey/buildd/ which lists > > "Currently-running builds" "Debian Testing, using multiarch/sbuild All > > packages" ... (unfortunately my current 'package of interest' -> mosquitto > > is missing) > > http://people.linaro.org/~wookey/buildd/testing/sbuild/latest/status.html Yeah, the 'currently running' bit is wrong too at the moment :-) We plan to set up a more permanent cross-buildd to get better stats on the archive. > > Here I see that not everything is passing. What exactly is the implication? This is work-in-progress, but we've just had some major steps forward so that now crossbuild-essential-$arch is installable in the archive. There are a few more core pieces to fix, then it's mostly a matter of making sure that upstreams+ debian packaging are cross-friendly. Now will be a much more satifying time to get stuck in than a few years ago :-) > > Is there an ongoing effort to get these packages to crosscompile? (Can one > > get involved [any learning sources recommended?] and join in?) Please do. There is a debian-cross mailing list, and we mostly use the #debian-bootstrap IRC channel to talk about this stuff. Wookey -- Principal hats: Linaro, Debian, Wookware, ARM http://wookware.org/
