Tools U-boot Terminal Errors

Hello guys,

i was following the guide http://elinux.org/Building_BBB_Kernel in order to build kernel linux on BBBlack. However, when i type on the terminal “make sandbox_defconfig tools-only” the outputs are the errors shown in the figure (consequently it doesn’t install mkimage program). How can i fix it?

DeepinScreenshot20170510173040.png