On Thu, Sep 28, 2017 at 12:25 AM, Eric Blake <ebl...@redhat.com> wrote:
> [adding gnulib] > > On 09/27/2017 04:36 PM, Christian Ehrhardt wrote: > > Hi, > > there seems to be an incompatibility to the last glibc due to [1]. > > Gnulib needs to be updated to track the glibc changes (it looks like > that is actually under way already), Yeah that seems to be part of the effort I linked. > then libvirt needs to pick up the > updated gnulib. I copied in current gnulib from git and it didn't resolve yet. But maybe it is just something that still is work in progress. > I'll leave the rest of your email intact in case it > helps gnulib readers, but I'll probably help resolve the issue when I > get a chance. > > I'm assuming you hit this failure on rawhide, as that is the platform > most likely to be using bleeding-edge glibc with the getopt changes? It was Ubuntu 17.10 (Artful) which is on 2.26 > > > Eventually this breaks gnulib unittests (and maybe more). > > Debugging went from an assert, to bidngin different symbols, to changed > > function names to different header resolution. > > > > Because it expects it to behave "posixly" but arguments are changed > > differently. > > FAIL: test-getopt-posix > > ======================= > > > > ../../../../gnulib/tests/test-getopt.h:754: assertion 'strcmp (argv[1], > > "donald") == 0' failed > > > > # get and build latest libvirt to get the local gnulib > > $ wget http://libvirt.org/sources/libvirt-3.7.0.tar.xz > > $ tar xf libvirt-3.7.0.tar.xz > > $ cd libvirt > > $ apt build-dep libvirt > > $ ./autogen.sh > > $ make -j4 > > > > > > You can run the following simplified test derived from the unit test (it > is > > much shorter, so easier to debug e.g. in -E). > > > > $ cat << EOF >> test1.c > > #include <config.h> > > #include <unistd.h> > > > > #include <stdbool.h> > > #include <stdio.h> > > #include <stdlib.h> > > > > int main (void) > > { > > return 0; > > } > > EOF > > $ gcc -I ./gnulib/lib -I . test1.c -H > > > > You can see in -H output already the difference in the paths of the > headers > > that it uses: > > > > Glibc <2.26 > > . ./config.h > > .. ./config-post.h > > . /usr/include/unistd.h > > [...] > > .. /usr/include/getopt.h > > > > Glibc >=2.26 > > . ./config.h > > .. ./config-post.h > > . ./gnulib/lib/unistd.h > > [...] > > > > ... /usr/include/x86_64-linux-gnu/bits/getopt_posix.h > > .... /usr/include/x86_64-linux-gnu/bits/getopt_core. > > > > > > If you build with -E you'll also see that it now uses getopt from glibc > > instead of the prefixed rpl_getopt from gnulib. > > > > It behaves as if it would not find gnulib and instead fall back to glibc. > > But it finds gnulib, instead due to glibc's changes its implementation is > > fetched before and due to that pulling in glibc's behavior while the unit > > test is verifying against the one it expects from gnulib. > > > > > > Sorry, but I don't see the right fix here yet - I could easily silence > the > > test but that is no fix. Especially if there might be implications due to > > handling the args (slightly) differently. > > > > I really wanted to come up with the same test against gnulib alone, but I > > was lost in the build system for too long and could not get the example > to > > fail without libvirt (OTOH I'm sure it would). > > > > Therefore I'm reaching out to you for your help and experience on the > build > > system what could be done. > > > > [1]: https://sourceware.org/ml/libc-alpha/2017-04/msg00115.html > > > > > > > > -- > > libvir-list mailing list > > libvir-l...@redhat.com > > https://www.redhat.com/mailman/listinfo/libvir-list > > > > -- > Eric Blake, Principal Software Engineer > Red Hat, Inc. +1-919-301-3266 > Virtualization: qemu.org | libvirt.org > > -- Christian Ehrhardt Software Engineer, Ubuntu Server Canonical Ltd
