I had the same problem after upgrading to Ubuntu 14.10. I found this link which describes the steps to be followed in order to apply the patch. It takes a while since you have to start all over again: downloading, building, installing... but it worked for me! Sorry I'm not an expert and I can't provide further details.
Here are the steps described in the link above:
If you want to patch and build mysql-workbench yourself, get the source from for 6.2.3. From the directory you downloaded it to, do:
wget 'http://dev.mysql.com/get/Downloads/MySQLGUITools/mysql-workbench-community-6.2.3-src.tar.gz'
tar xvf mysql-workbench-community-6.2.3-src.tar.gz && cd mysql-workbench-community-6.2.3-src
wget -O patch-glib.diff 'http://bugs.mysql.com/file.php?id=21874&bug_id=74147'
patch -p0 < patch-glib.diff
sudo apt-get build-dep mysql-workbench
sudo apt-get install libgdal-dev
cd build
cmake .. -DBUILD_CONFIG=mysql_release
make
sudo make install
Hope this can be helpful.