Fixing build issues on mac.
Fixing build issues on mac.

NicolasSchnitzler/medInria-public,rdebroiz/medInria-public,aabadie/medInria-public,NicolasSchnitzler/medInria-public,rdebroiz/medInria-public,aabadie/medInria-public,rdebroiz/medInria-public,aabadie/medInria-public,NicolasSchnitzler/medInria-public