Dear grasp developers,
it appears that the Makefile contains the wrong jj2lsj90 target. As far as I can understand, this is due to the fact that the last commit removed jj2lsj90 in favor for jj2lsj90_2025. So the fix would be simply to either renaming the jj2lsj90_2025 back to jj2lsj90 or modifying the Makefile to reflect the change.
I have tried to compile with CMake but haven't had any success with that.