How to uninstall gcc installed from source?

Question

How can I uninstall a gcc build which I installed from source.I am using gcc 4.9 and I'm on ubuntu 12.04.

Or is there a way to upgrade to latest gcc versions through the ubuntu repository?

Answer 1

When you build a package from source there is unfortunately no magic uninstall usually, however you can approximate this, credit to this mailing list thread.

Basically you should install again into a temporary directory and list all the files created in said directory, then you can delete all of them from the main system through a script.

Here is an example of a script to uninstall GCC in this way:

make install DESTDIR=/tmp/gccinst
find /tmp/gccinst | sed -e s,/tmp/gccinst,, | \
(while read F; do rm "$F"; done)

Run it from inside the gcc source directory as root.

To answer your second question you can install the latest gcc available in the ubuntu repo with:

apt-get install gcc

Overlay repos may have newer versions, I have seen a suggestion there is a newer version at ubuntu-toolchain-r/test (install via):

sudo add-apt-repository ppa:ubuntu-toolchain-r/test

But I am not sure if they have added 4.9 there yet. If not you will indeed have to install from source.

EDIT:

It looks like @roelofs found a better guide to install the repo in his answer, so go look there too and remember to give him an upvote if it helps :)

Answer 2

In GCC 5.1.0, although there is no top-level uninstall target, some directories do have it, in particular gcc, so you can do:

cd build/gcc
sudo make uninstall

This does not remove everything that was installed, but it removes major executables like gcc, g++, cpp... contained in that directory, so it might be enough.