Configure and Compile U-Boot stuck in

i just follow up everythings same with the link…

and following below… and then… below…

$ git checkout rel_socfpga_v2013.01.01_15.09.01_pr
error: Your local changes to the following files would be overwritten by checkout:
arch/arm/cpu/armv7/config.mk
arch/arm/cpu/armv7/socfpga/sdram.c
arch/arm/cpu/armv7/socfpga/spl.c
arch/arm/include/asm/arch-socfpga/sdram.h
arch/arm/lib/board.c
board/altera/socfpga/build.h
common/spl/spl.c
drivers/spi/cadence_qspi_apb.c
include/linux/compiler-gcc.h
include/linux/compiler-gcc5.h
include/status_led.h
Please, commit your changes or stash them before you can switch branches.
Aborting

how can i do for next? give me any answer…