Hi, effectively the j4 flag is a lot faster! So i tried with the new and the old SFML cmake commands, it's working when i go to attract just after the install but after a reboot, i've some errors like "no file or directory" about libsfml-graphics.so.2.4 and libsfml-windows.so.2.4 files.
But the files are in the /usr/local/lib directory. However there were no errors during the install. My firmware is :
Linux retropie 4.4.13-v7+ #894 SMP Mon Jun 13 13:13:27 BST 2016 armv7l GNU/Linux