Richard Holloway's answer to this thread nicely explains how to upgrade from 4.6.3 to 4.7.0 (on 12.04, in my case) but I would like to upgrade to 4.7.1, which has been available for awhile. However there is no package g++-4.7.1 and I don't know otherwise how to do it, does anyone else?
Wow, this was excruciating. Here's how I did it (NB, for a 32-bit system):
$sudo apt-get install gcc-multilib
$sudo apt-get install m4
Download mpfr, configure, make, make install
Download gmp, configure, make, make install
Download mpc, configure, make, make install
In order to compensate for insufficient path information, added this to .bashrc
export LD_LIBRARY_PATH=/usr/local/lib:$LD_LIBRARY_PATH
export LIBRARY_PATH=/usr/lib/i386-linux-gnu export
export C_INCLUDE_PATH=/usr/include/i386-linux-gnu export
export CPLUS_INCLUDE_PATH=/usr/include/i386-linux-gnu
the former I got from here and the latter from here, modified appropriately for my install locations.
.7. Add these symlinks for the same reason:
$sudo ln -s /usr/include/i386-linux-gnu/gnu/stubs-32.h /usr/include/gnu
$sudo ln -s /usr/lib/i386-linux-gnu/crti.o /usr/lib/crti.o
$sudo ln -s /usr/lib/i386-linux-gnu/crt1.o /usr/lib/crt1.o
$sudo ln -s /usr/lib/i386-linux-gnu/crtn.o /usr/lib/crtn.o
$sudo ln -s /usr/local/lib/libmpc.so.3
/usr/lib/libmpc.so.3
.8. Download g++-4.7.1, configure, make, make install
