Thanks for the tips! They helped me a lot. I managed to build Cabbage!
The only problem now is that the UI doesn't get updated properly. So menus pile up on top of each other. When I load an example the window size will change but it still show the start-up screen. Also I cannot get the source editor to open up.
I'll leave a note of what worked to build on Raspbian for reference.
I had to update gcc and g++ to version 4.8
sudo apt-get install gcc-4.8
sudo apt-get install g++-4.8
I then changed the symlinks to gcc and g++ to point to the 4.8 versions, so that the gcc and g++ commands pick the right version.
ln -s /usr/bin/gcc-4.8 /usr/bin/gcc
ln -s /usr/bin/g++-4.8 /usr/bin/g++
Also make sure to have the correct version of CSound installed (the default was 5.x, and 6.0.3 is needed). Building CSound is easy, just follow these instructions:
The last thing is to make sure the VST SDK is at ~/SDKs/vstsdk2.4
I was not able to make it work with any other location, some Juce sources would fail.