Bug#925820: sagemath: ftbfs with GCC-9

[Gianfranco Costamagna]

control: fixed -1 8.8-1
control: close -1
On Wed, 27 Mar 2019 19:47:55 +0000 Matthias Klose <doko at debian.org> wrote:
> Package: src:sagemath
> Version: 8.6-6
> Severity: normal
> Tags: sid bullseye
> User: debian-gcc at lists.debian.org
> Usertags: ftbfs-gcc-9
> 
> 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-9/g++-9, but succeeds to build with gcc-8/g++-8. The
> severity of this report will be raised before the bullseye release,
> so nothing has to be done for the buster release.
> 
> The full build log can be found at:
> http://people.debian.org/~doko/logs/gcc9-20190321/sagemath_8.6-6_unstable_gcc9.log
> The last lines of the build log are at the end of this report.
> 
> To build with GCC 9, either set CC=gcc-9 CXX=g++-9 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-9/porting_to.html
> 
> GCC 9 also passes the linker option --as-needed by default; typical
> build issues are passing libraries before object files to the linker,
> or underlinking of convenience libraries built from the same source.
> 
> [...]
> Error while executing Python code.
> Saved trace to /<<PKGBUILDDIR>>/debian/test/crash_logs/crash_jfpzc0q7.log
> ------------------------------------------------------------------------
> Unhandled SIGABRT: An abort() occurred.
> This probably occurred because a *compiled* module has a bug
> in it and is not properly wrapped with sig_on(), sig_off().
> Python will now terminate.
> ------------------------------------------------------------------------
> 
> **********************************************************************
> sage -t --long --warn-long 57.0 src/sage/graphs/generators/families.py
> **********************************************************************
> File "src/sage/graphs/generators/families.py", line 3179, in sage.graphs.generators.families.MathonPseudocyclicStronglyRegularGraph
> Failed example:
>     L = sum(i*(r[a]-r[b]) for i,(a,b) in zip(range(1,len(ff)+1), ff)); L
> Expected:
>     [ 0  1 -1 -3 -2 -4  3  4  2]
>     [-1  0  1 -4 -3 -2  2  3  4]
>     [ 1 -1  0 -2 -4 -3  4  2  3]
>     [ 3  4  2  0  1 -1 -3 -2 -4]
>     [ 2  3  4 -1  0  1 -4 -3 -2]
>     [ 4  2  3  1 -1  0 -2 -4 -3]
>     [-3 -2 -4  3  4  2  0  1 -1]