You can uninstall or removes an installed gcc-4.7-arm-linux-gnueabi-base package itself from Ubuntu 14.04 LTS (Trusty Tahr) through the terminal,
$ sudo apt-get remove gcc-4.7-arm-linux-gnueabi-base
If you would like to remove gcc-4.7-arm-linux-gnueabi-base and it's dependent packages which are no longer needed from Ubuntu,
$ sudo apt-get remove --auto-remove gcc-4.7-arm-linux-gnueabi-base
If you use with purge options to gcc-4.7-arm-linux-gnueabi-base package all the configuration and dependent packages will be removed.
$ sudo apt-get purge gcc-4.7-arm-linux-gnueabi-base
If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.
$ sudo apt-get purge --auto-remove gcc-4.7-arm-linux-gnueabi-base