Heisenbug!

FreeDOOM e3m8 uses only vanilla features, it has no extra colormaps or anything, does not even exceed visplane limits or anything. Yet, upon loading of the map every single pure vanilla engine crashes (or in true vanilla doom, freezes). I put a compiled version of the original source under gdb, and it ran perfectly. So I couldn't find the source of the bug. I tried again to do that with choco-doom. choco-doom segfaulted, but I had no symbols so I couldn't tell where. wtf. I even decomposed it into a .dwd file with my own wad2dwd converter, and rebuilt it with doombsp, and still crashes vanilla, but runs in all other ports.

Does the player start directly on top of a vertex by some chance?

I think I've found it - too many scrolling lines. Does the map really need 142 of them?

Yes it was the scrolling lines :) Now my only question was why did it work the first time I popped xdoom in the debugger? D:

Don't know if I can help you there, maybe the gods were smiling on you that day?

I guess... Well thank you :D