nios eclipse :cygpath: can't convert empty path

kangqiaoyibie

**** Build of configuration Default for project mynios_ch395 ****

make all
系统找不到指定的路径。
系统找不到指定的路径。
Info: Building ../mynios_ch395_bsp/
make --no-print-directory -C ../mynios_ch395_bsp/
cygpath: can't convert empty path
process_begin: CreateProcess(NULL, pwd, ...) failed.
make[1]: *** No rule to make target `/system.h', needed by `all'.  Stop.
make: *** [../mynios_ch395_bsp/-recurs-make-lib] Error 2

**** Build Finished ****
不知道怎么解。。。。
我安装了MINGW，指定了环境变量，还是不行