This project is aobut how to build a GCC Cross-Compiler, in my blog http://fichugh.blogspot.tw/2016/02/how-to-build-gcc-cross-compiler.html
I writed a script to test (download and build) automatically, the thing you have to do is modified the wget-list file for the newest version of packages, and run run_it.sh
my build time is around 10 m
just try :
$ time sh run_it.sh