http://archive.ubuntu.com/ubuntu/pool/main/g/gcc-4.8/

http://packages.ubuntu.com/trusty/devel/g++-4.8

gcc:

gcc-4.8_4.8.4-2ubuntu1~14.04.3_amd64.deb

gcc-4.8-base_4.8.4-2ubuntu1~14.04.3_amd64.deb

gcc-4.8-doc_4.8.4-2ubuntu1~14.04.3_all.deb

gcc-4.8-multilib_4.8.4-2ubuntu1~14.04.3_amd64.deb

gcc-4.8-plugin-dev_4.8.4-2ubuntu1~14.04.3_amd64.deb

 mv gcc-4.8 gcc

g++:

g++-4.8_4.8.4-2ubuntu1~14.04.3_amd64.deb

g++-4.8-multilib_4.8.4-2ubuntu1~14.04.3_amd64.deb

libstdc++-4.8-dev_4.8.4-2ubuntu1~14.04.3_amd64.deb

cpp-4.8_4.8.4-2ubuntu1~14.04.3_amd64.deb

 mv g++-4.8 g++

cmake

1.sudo ./bootstrap

2.sudo make

3.sudo make install

4.cmake --version

Ubuntu1404