Libdl.so missing DSO from command line (undefined reference)

[spiketg]

I've been porting this code to work with opencv3. So far I have made it through most of the compilation but I keep getting this error when its almost complete. I have looked at a number of occurances of this issue but none of the solutions have worked for me as yet. Any help would be greatly appreciated then, once the OpenCV3 version is working I'd be happy to share my code.

So far I've tried:
-creating the symbolic link to libdl.so manually (as this solved a few similar errors I had earlier in the compliation)
-adding -ldl as a flag, and in the cmakelists

• rearranging the order of the included libraries as that has been known to have an effect

so far nothing has worked.
any advice?

[ 92%] Linking CXX executable ../bin/TestBump /usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/7/../../../../lib/libhdf5.a(H5PL.o): undefined reference to symbol 'dlclose@@GLIBC_2.2.5' /usr/lib/gcc/x86_64-linux-gnu/7/../../../x86_64-linux-gnu/libdl.so: error adding symbols: DSO missing from command line collect2: error: ld returned 1 exit status config/CMakeFiles/TestBump.dir/build.make:149: recipe for target 'bin/TestBump' failed make[2]: *** [bin/TestBump] Error 1 CMakeFiles/Makefile2:196: recipe for target 'config/CMakeFiles/TestBump.dir/all' failed make[1]: *** [config/CMakeFiles/TestBump.dir/all] Error 2 Makefile:129: recipe for target 'all' failed make: *** [all] Error 2