[Debian-med-packaging] Bug#984058: igraph: ftbfs with GCC-11

[Matthias Klose]

Package: src:igraph
Version: 0.8.5+ds1-1
Severity: normal
Tags: sid bookworm
User: debian-gcc at lists.debian.org
Usertags: ftbfs-gcc-11

[This bug is not targeted to the upcoming bullseye release]

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-11/g++-11, but succeeds to build with gcc-10/g++-10. The
severity of this report will be raised before the bookworm release,
so nothing has to be done for the bullseye release.

The full build log can be found at:
http://people.debian.org/~doko/logs/20210228/filtered/gcc11/igraph_0.8.5+ds1-1_unstable_gcc11.log
The last lines of the build log are at the end of this report.

To build with GCC 11, either set CC=gcc-11 CXX=g++-11 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-11/porting_to.html

GCC 11 defaults to the GNU++17 standard.  If your package installs
header files in /usr/include, please don't work around C++17 issues
by choosing a lower C++ standard for the package build, but fix these
issues to build with the C++17 standard.

[...]

Thread-safety tests

247: Simple error handling test :                    skipped (mt.at:26)
248: Thread-safe ARPACK:                             skipped (mt.at:31)

Spectral coarse graining

249: Solving the SCG problem (igraph_scg_grouping) : ok
250: Solving the SCG problem, adjacency matrix (igraph_scg_grouping) : ok
251: Solving the SCG problem, stochastic matrix (igraph_scg_grouping) : ok
252: Solving the SCG problem, laplacian matrix (igraph_scg_grouping) : ok
253: SCG semi-projectors, symmetric (igraph_scg_semiprojectors) : ok
254: SCG semi-projectors, stochastic (igraph_scg_semiprojectors) : ok
255: SCG semi-projectors, laplacian (igraph_scg_semiprojectors) : ok
256: SCG of a graph, adjacency matrix (igraph_scg) : ok
257: SCG of a graph, stochastic matrix (igraph_scg) : ok
258: SCG of a graph, laplacian matrix (igraph_scg) : ok

Random number generators

259: Random seed:                                    ok
260: RNG reproducibility:                            ok
261: MT19937 RNG on 64 bit machines:                 ok
262: Exponentially distributed random numbers:       ok
263: Random sampling from consecutive sequence:      ok
264: Fisher-Yates shuffle:                           ok

Quick sort

265: Regular qsort (igraph_qsort):                   ok
266: qsort with extra argument (igraph_qsort_r):     ok

Maximum matchings

267: Maximum bipartite matching (igraph_maximum_bipartite_matching):  ok

Embeddings

268: Adjacency spectral embedding (igraph_adjacency_spectral_embedding):  ok

## ------------- ##
## Test results. ##
## ------------- ##

ERROR: 266 tests were run,
9 failed unexpectedly.
2 tests were skipped.
## -------------------------- ##
## testsuite.log was created. ##
## -------------------------- ##

Please send `tests/testsuite.log' and all information you think might help:

   To: <igraph at igraph.org>
   Subject: [igraph 0.8.5] testsuite: 65 69 77 85 166 178 189 199 231 failed

You may investigate any problem if you feel able to do so, in which
case the test suite provides a good starting point.  Its output may
be found below `tests/testsuite.dir'.

make[3]: *** [Makefile:503: check-local] Error 1
make[3]: Leaving directory '/<<PKGBUILDDIR>>/_build/tests'
make[2]: *** [Makefile:366: check-am] Error 2
make[2]: Leaving directory '/<<PKGBUILDDIR>>/_build/tests'
make[1]: *** [Makefile:499: check-recursive] Error 1
make[1]: Leaving directory '/<<PKGBUILDDIR>>/_build'
dh_auto_test: error: cd _build && make -j4 check VERBOSE=1 returned exit code 2
make: *** [debian/rules:8: binary] Error 25
dpkg-buildpackage: error: debian/rules binary subprocess returned exit status 2