wget ftp://xmlsoft.org/libxml2/libxml2-2.7.2.tar.gz
./configure CC=aarch64-linux-gnu-gcc --host=arm-linux --prefix=/home/book/tool/libxml2-2.7.2/build_out --with-python=no --without-zlib 
make 
make install

问题：
–without-zlib选项很重要，如果不加此选项，make的时候会提示如下错误:

./.libs/libxml2.so: undefined reference to `gzopen'  
./.libs/libxml2.so: undefined reference to `gzclose'  
./.libs/libxml2.so: undefined reference to `deflate'  
./.libs/libxml2.so: undefined reference to `gzrewind'  
./.libs/libxml2.so: undefined reference to `gzwrite'  
./.libs/libxml2.so: undefined reference to `crc32'  
./.libs/libxml2.so: undefined reference to `deflateEnd'  
./.libs/libxml2.so: undefined reference to `gzdopen'  
./.libs/libxml2.so: undefined reference to `deflateInit2_'  
./.libs/libxml2.so: undefined reference to `gzread'  
collect2: ld returned 1 exit status