So, firstly, this could be an issue with my files I suppose, however I don't recall having this issue in Windows (with the same files).
I compiled from source, latest release, Manjaro Linux.
For DOOM, or DOOM 2, as soon as I select my difficulty level (or a demo decides it wants to play), the game just freezes.
Can't even ^C the console to close it, I have to kill the process!
Here is the output after trying to start the game (all output before that appears normal): https://pastebin.com/FCn3zCnR
Interestingly, when I tried a mod (in the ipk3 format), it worked fine, I was able to load into the first level and everything seemed fine.
Tried a few others, and they seemed to work as well.
So, I think there's definitely some relation either to the files themselves, or just to something relating to the original WAD format that isn't working? Or I could be totally wrong. Most of the console output that I actually understand, seems related to audio, but there weren't any issues with audio, at least on the title screens.