[pkg-lxc-devel] Bug#853531: lxc: ftbfs with GCC-7

[Matthias Klose]

Package: src:lxc
Version: 1:2.0.7-1
Severity: normal
Tags: sid buster
User: debian-gcc at lists.debian.org
Usertags: ftbfs-gcc-7

Please keep this issue open in the bug tracker for the package it
was filed for.  If a fix in another package is required, please
file a bug for the other package (or clone), and add a block in this
package. Please keep the issue open until the package can be built in
a follow-up test rebuild.

The package fails to build in a test rebuild on at least amd64 with
gcc-7/g++-7, but succeeds to build with gcc-6/g++-6. The
severity of this report may be raised before the buster release.
There is no need to fix this issue in time for the stretch release.

The full build log can be found at:
http://people.debian.org/~doko/logs/gcc7-20170126/lxc_2.0.7-1_unstable_gcc7.log
The last lines of the build log are at the end of this report.

To build with GCC 7, either set CC=gcc-7 CXX=g++-7 explicitly,
or install the gcc, g++, gfortran, ... packages from experimental.

  apt-get -t=experimental install g++ 

Common build failures are new warnings resulting in build failures with
-Werror turned on, or new/dropped symbols in Debian symbols files.
For other C/C++ related build failures see the porting guide at
http://gcc.gnu.org/gcc-7/porting_to.html

[...]
conf.c: In function 'lxc_assign_network':
conf.c:3096:25: error: '%lu' directive output may be truncated writing between 1 and 20 bytes into a region of size 19 [-Werror=format-truncation=]
   snprintf(pidstr, 19, "%lu", (unsigned long) pid);
                         ^~~
conf.c:3096:24: note: using the range [1, 18446744073709551615] for directive argument
   snprintf(pidstr, 19, "%lu", (unsigned long) pid);
                        ^~~~~
In file included from /usr/include/stdio.h:938:0,
                 from conf.c:35:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: format output between 2 and 21 bytes into a destination of size 19
   return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        __bos (__s), __fmt, __va_arg_pack ());
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
confile.c: In function 'network_new_hwaddrs':
confile.c:2889:38: error: '%02x' directive output may be truncated writing between 2 and 8 bytes into a region of size 6 [-Werror=format-truncation=]
  snprintf(hwaddr, 18, "00:16:3e:%02x:%02x:%02x",
                                      ^~~~
confile.c:2889:23: note: using the range [0, 4294967295] for directive argument
  snprintf(hwaddr, 18, "00:16:3e:%02x:%02x:%02x",
                       ^~~~~~~~~~~~~~~~~~~~~~~~~
confile.c:2889:23: note: using the range [0, 4294967295] for directive argument
In file included from /usr/include/stdio.h:938:0,
                 from confile.c:24:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: format output between 18 and 36 bytes into a destination of size 18
   return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        __bos (__s), __fmt, __va_arg_pack ());
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
Makefile:1604: recipe for target 'liblxc_la-confile.lo' failed
make[4]: *** [liblxc_la-confile.lo] Error 1
cc1: all warnings being treated as errors
Makefile:1597: recipe for target 'liblxc_la-conf.lo' failed
make[4]: *** [liblxc_la-conf.lo] Error 1
libtool: compile:  gcc -DHAVE_CONFIG_H -I. -I../../src -Wdate-time -D_FORTIFY_SOURCE=2 -fPIC -DPIC -DLXCROOTFSMOUNT=\"/usr/lib/x86_64-linux-gnu/lxc/rootfs\" -DLXCPATH=\"/var/lib/lxc\" -DLXC_GLOBAL_CONF=\"/etc/lxc/lxc.conf\" -DLXCINITDIR=\"/usr/lib/x86_64-linux-gnu\" -DLIBEXECDIR=\"/usr/lib/x86_64-linux-gnu\" -DLXCTEMPLATEDIR=\"/usr/share/lxc/templates\" -DLXCTEMPLATECONFIG=\"/usr/share/lxc/config\" -DLOGPATH=\"/var/lib/lxc\" -DLXC_DEFAULT_CONFIG=\"/etc/lxc/default.conf\" -DLXC_USERNIC_DB=\"/run/lxc/nics\" -DLXC_USERNIC_CONF=\"/etc/lxc/lxc-usernet\" -DDEFAULT_CGROUP_PATTERN=\"/lxc/%n\" -DRUNTIME_PATH=\"/run\" -DSBINDIR=\"/usr/sbin\" -I ../../src -I ../../src/lxc -I ../../src/lxc/bdev -I ../../src/lxc/cgroups -DHAVE_APPARMOR -DHAVE_SELINUX -DUSE_CONFIGPATH_LOGS -DHAVE_SECCOMP -pthread -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -Wall -Werror -c lxccontainer.c -o liblxc_la-lxccontainer.o >/dev/null 2>&1
make[4]: Leaving directory '/<<PKGBUILDDIR>>/src/lxc'
Makefile:444: recipe for target 'all-recursive' failed
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory '/<<PKGBUILDDIR>>/src'
Makefile:383: recipe for target 'all' failed
make[2]: *** [all] Error 2
make[2]: Leaving directory '/<<PKGBUILDDIR>>/src'
Makefile:536: recipe for target 'all-recursive' failed
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory '/<<PKGBUILDDIR>>'
dh_auto_build: make -j64 returned exit code 2
debian/rules:10: recipe for target 'build' failed
make: *** [build] Error 2
dpkg-buildpackage: error: debian/rules build gave error exit status 2