Can't build on arch-linux

[FranciscoVasconcelos]

I'm getting the following error while trying to build in arch-linux:

[  4%] Linking CXX shared library lib/libvsr_shared.so
/usr/bin/cmake -E cmake_link_script CMakeFiles/vsr_shared.dir/link.txt --verbose=1
/usr/bin/c++ -fPIC  -g -O3 -ftemplate-depth-1200 -Wno-switch -Wno-deprecated-declarations -Wno-int-to-pointer-cast -DVSR_PRECISION_DOUBLE -O2 -g -DNDEBUG -shared -Wl,-soname,libvsr_shared.so -o lib/libvsr_shared.so CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_cubicLattice.cpp.o CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_frame.cpp.o CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_op.cpp.o CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_round.cpp.o   -L/home/francisco/git-repos/versor/build/lib
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_frame.cpp.o:(.bss+0x0): multiple definition of `vsr::cga::pointsOnSphere'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x0): first defined here
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_frame.cpp.o:(.bss+0x1): multiple definition of `vsr::cga::pointOnSphere'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x1): first defined here
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_frame.cpp.o:(.bss+0x2): multiple definition of `vsr::cga::pairOnSphere'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x2): first defined here
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_frame.cpp.o:(.bss+0x3): multiple definition of `vsr::cga::pointsOnCircle'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x3): first defined here
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_frame.cpp.o:(.bss+0x4): multiple definition of `vsr::cga::pointOnCircle'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x4): first defined here
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_frame.cpp.o:(.bss+0x5): multiple definition of `vsr::cga::pointOnLine'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x5): first defined here
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_op.cpp.o:(.bss+0x0): multiple definition of `vsr::cga::pointsOnSphere'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x0): first defined here
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_op.cpp.o:(.bss+0x1): multiple definition of `vsr::cga::pointOnSphere'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x1): first defined here
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_op.cpp.o:(.bss+0x2): multiple definition of `vsr::cga::pairOnSphere'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x2): first defined here
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_op.cpp.o:(.bss+0x3): multiple definition of `vsr::cga::pointsOnCircle'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x3): first defined here
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_op.cpp.o:(.bss+0x4): multiple definition of `vsr::cga::pointOnCircle'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x4): first defined here
/usr/bin/ld: CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_op.cpp.o:(.bss+0x5): multiple definition of `vsr::cga::pointOnLine'; CMakeFiles/vsr_shared.dir/src/space/vsr_cga3D_external_linkage.cpp.o:(.bss+0x5): first defined here
collect2: error: ld returned 1 exit status
make[2]: *** [CMakeFiles/vsr_shared.dir/build.make:161: lib/libvsr_shared.so] Error 1
make[2]: Leaving directory '/home/francisco/git-repos/versor/build'
make[1]: *** [CMakeFiles/Makefile2:546: CMakeFiles/vsr_shared.dir/all] Error 2
make[1]: Leaving directory '/home/francisco/git-repos/versor/build'
make: *** [Makefile:146: all] Error 2

[StumpfMichael]

I have the same problem in Ubuntu 20.04.

Perhaps symbols from versor/include/vsr/space/vsr_cga3D_op.h are included several times.

[StumpfMichael]

Ok, in this h-file is a section with lamdas, defined with "auto" which has external linkage by default. To change it to local linkage just add "const" and you should be able to build the libraries. Example
auto pointsOnSphere ... => const auto pointsOnSphere ...

[Mgomez-01]

I just went through the same problem, and adding const to the declarations fixed it for me.