gcc7: some conda builds are failing

[looooo]

please have a look at:
conda-forge/netgen-feedstock#14

For linux we build for gcc (4.8 / 7.3) x py (2.7 / 3.6 / 3.7). So this is alread a quite big build-matrix. Maybe someone can have a look and give some hints for the problems. Maybe some modifications in the source could make netgen more solid for compiling on different system / distros.

[looooo]

I am now trying to build everything without visualization. But there is still a problem with the visuzalization-stuff:

-O3 -DNDEBUG -fPIC   -std=gnu++14 -MD -MT libsrc/occ/CMakeFiles/occvis.dir/vsocc.cpp.o -MF libsrc/occ/CMakeFiles/occvis.dir/vsocc.cpp.o.d -o libsrc/occ/CMakeFiles/occvis.dir/vsocc.cpp.o -c ../libsrc/occ/vsocc.cpp
In file included from ../libsrc/include/../visualization/visual.hpp:20:0,
                 from ../libsrc/include/visual.hpp:1,
                 from ../libsrc/occ/vsocc.cpp:25:
../libsrc/include/../visualization/../include/incopengl.hpp:12:14: fatal error: GL/glu.h: No such file or directory
 #    include <GL/glu.h>

I guess this file shouldn't be part of the build for -DUSE_GUI=OFF \

[looooo]

should be fixed with #21

But now I am seeing another problem for osx:

import: 'netgen'
Traceback (most recent call last):
  File "/Users/distiller/miniconda3/conda-bld/netgen_1543334948821/test_tmp/run_test.py", line 2, in <module>
    import netgen
  File "/Users/distiller/miniconda3/conda-bld/netgen_1543334948821/_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placeh/lib/python3.7/site-packages/netgen/__init__.py", line 17, in <module>
    from . import libngpy
ImportError: dlopen(/Users/distiller/miniconda3/conda-bld/netgen_1543334948821/_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placeh/lib/python3.7/site-packages/netgen/libngpy.so, 2): Symbol not found: _Ng_Redraw

[luzpaz]

https://ngsolve.org/forum/ngspy-forum/722-netgen-and-ngsolve-github-repo-pending-prs