libobjc2 | Objective-C runtime library intended for use with Clang | Compiler library

Although I cannot tell what exactly the bug was in my case, I got some external help and together we came up with a solution that worked for me. For debugging purposes, we created a test user account in my Ubuntu environment and repeated the whole process. It worked flawlessly. We concluded that something must have been wrong locally with regard to my user account. I am sure there was something wrong with my environment variables, although I failed to clearly identify the bug (I am a Linux beginner). I chose the easy way out, backed up important files, deleted and re-created my root user account and then it worked. I hope, this may help any other who has the same problem. @skaak, thank you for your help and suggestions!