You can static assert that the offset of your VLA member is the size of your structure. I haven't thought about alignment requirements, but for many needs it will do the job.
I had to disable my GPUs and use Intel so I could get inside and manually install NVIDIA driver. I don't have much experience with setting boot options. Shouldn't have to take 2 years to fix, though, but I guess it was a weird card.
Not just that, but everyone has a unique way they walk, called their gait, so if you are identified once (usually by facial recognition) your gait can be used to identify you forever after, even if you try to hide your identity.
Only way to go undetected then is to purposely change your gait and other things, but the important thing here is:
We are at a point where the effort you have to go through to remain anonymous in the public is so high that it may not be worth the effort.