RF lens on a 5D DSLR, anyone?

I'm guessing it is not possible since I am not finding any information on the 2 being paired. But, I am interested to know if the RF lenses can mount on a DSLR such as the 5DSR.

Thanks for any info.

They are getting mounted. But focus range is limited to close.

Not possible in any practical way because of the mirrorbox. RF flange distance is much shorter

I would think that because of the flange distance difference, 20mm for the R and 44 for the EF, and the difference in the number of pins, R is totally incompatible with EF and EF-S. The only thing the same is the mount diameter.

One other difference, the R mount is keyed differently.

Thanks to you all for the clarification.