[kernel]: error: ‘PATH_MAX’ undeclared (first use in this function)

内核2.6.18.8交叉编译问题，描述如下：

scripts/mod/sumversion.c: In function ‘get_src_version’:
scripts/mod/sumversion.c:384: error: ‘PATH_MAX’ undeclared (first use
in this function)
scripts/mod/sumversion.c:384: error: (Each undeclared identifier is
reported only once
scripts/mod/sumversion.c:384: error: for each function it appears in.)
scripts/mod/sumversion.c:384: warning: unused variable ‘filelist’
make[3]: *** [scripts/mod/sumversion.o] Error 1
make[2]: *** [scripts/mod] Error 2
make[1]: *** [scripts] Error 2
make[1]: Leaving directory `/home/nios2/uClinux-dist/linux-2.6.x'
make: *** [linux] Error 1

解决方法：

# vi scripts/mod/sumversion.c

头文件包含中查看是否有limits.h，若没有，包含进去即可

#inlcude <limits.h>