The GPL is (in)famously viral. You can't base something on a GPLed codebase and say that your thing isn't covered by the GPL. The GPL is specifically designed to forbid that specific thing.
If Linux DRM weren't licensed under more permissive terms, OpenBSD simply wouldn't permit its inclusion.
Clearly two different files don't share the same address space. So no problem.
When I compile my GPL code with a copy of somebody else's MIT code into a binary (shared address space), other people's copy of that MIT code is still MIT licensed.