Hi Nicolas,
I am running Ubuntu 16.04 64bit. Yes, I ran the command sudo ldconfig. I just noticed that cmake generated a couple of warnings. One was associated with 'Policy CMP0026 is not set' and the other was 'Policy CMP0045 is not set'. But the cmake command for python module installation produced only warnings associated with 'Policy CMP0045 is not set'. The make and install commands ran without any warnings or errors. And I saw an error message on terminal after closing GRC - 'XML parser: Found 1 erroneous XML file while loading the block tree (see "Help/Parser errors" for details)' so I checked the XML file again and all entries are correct.
Best
Sakthivel