ARCH = arm
CROSS_COMPILE = /usr/local/arm/3.3.2/bin/arm-linux-

之后，正式编译busybox，哇呜啊，出现了UBI的错误哦。

miscutils/ubi_tools.c:63:26: error: mtd/ubi-user.h: No such file or directory
miscutils/ubi_tools.c: In function 'ubi_tools_main':
miscutils/ubi_tools.c:133: error: 'UBI_DEV_NUM_AUTO' undeclared (first use in this function)
miscutils/ubi_tools.c:133: error: (Each undeclared identifier is reported only once
miscutils/ubi_tools.c:133: error: for each function it appears in.)
miscutils/ubi_tools.c:134: error: 'UBI_VOL_NUM_AUTO' undeclared (first use in this function)
miscutils/ubi_tools.c:153: error: storage size of 'req' isn't known
miscutils/ubi_tools.c:161: error: 'UBI_IOCATT' undeclared (first use in this function)
miscutils/ubi_tools.c:153: warning: unused variable 'req'
miscutils/ubi_tools.c:167: error: 'UBI_IOCDET' undeclared (first use in this function)
miscutils/ubi_tools.c:170: error: storage size of 'req' isn't known
miscutils/ubi_tools.c:177: error: 'UBI_MAX_VOLUME_NAME' undeclared (first use in this function)
miscutils/ubi_tools.c:184: error: 'UBI_STATIC_VOLUME' undeclared (first use in this function)
miscutils/ubi_tools.c:186: error: 'UBI_DYNAMIC_VOLUME' undeclared (first use in this function)
miscutils/ubi_tools.c:195: error: 'UBI_IOCMKVOL' undeclared (first use in this function)
miscutils/ubi_tools.c:170: warning: unused variable 'req'
miscutils/ubi_tools.c:201: error: 'UBI_IOCRMVOL' undeclared (first use in this function)
miscutils/ubi_tools.c:204: error: storage size of 'req' isn't known
miscutils/ubi_tools.c:214: error: 'UBI_IOCRSVOL' undeclared (first use in this function)
miscutils/ubi_tools.c:204: warning: unused variable 'req'
miscutils/ubi_tools.c:222: error: 'UBI_IOCVOLUP' undeclared (first use in this function)
make[1]: *** [miscutils/ubi_tools.o] 错误 1
make: *** [miscutils] 错误 2

出现这么多的错误，核心问题就是出现在miscutils/ubi_tools.c:63:26: error: mtd/ubi-user.h: No such file or directory这个上面，无法找到mtd/ubi-user.h头文件，查阅了相关资料后，原来这是一个Linux下新支持的UBI文件系统，需要手工加入。从Linux2.6.29的include\mtd\ubi-user.h拷贝到busybox下的include\mtd下，如果busybox下的include没有mtd文件夹，那就先建立一个mtd文件夹，然后复制了。这样做了之后，编译就OK了。出现下面的信息就说明编译成功了。

LINK busybox_unstripped
Trying libraries: crypt m
Library crypt is not needed, excluding it
Library m is needed, can't exclude it (yet)
Final link with: m
DOC busybox.pod
DOC BusyBox.txt
DOC busybox.1
DOC BusyBox.html

之后就是安装busybox了。make install 等一会就可以看到_install文件夹了。差不多300多MB啊。当然你可以根据自己的需要去裁剪busybox啊。见下面部分信息：

./_install//usr/sbin/ubimkvol -> ../../bin/busybox
./_install//usr/sbin/ubirmvol -> ../../bin/busybox
./_install//usr/sbin/ubirsvol -> ../../bin/busybox
./_install//usr/sbin/ubiupdatevol -> ../../bin/busybox
./_install//usr/sbin/udhcpd -> ../../bin/busybox

--------------------------------------------------
You will probably need to make your busybox binary
setuid root to ensure all configured applets will
work properly.