It may be close to a technical impossibility, but the Circle compiler by Sean Baxter is attempting it. That's based on an aggressive "de-pointerization" (see [1] in particular for details). There's also academic work[2] to compile C++ to shaders. I agree that it's an open question how well that will work out.
Also as pointed out elsethread, now that buffer device address is starting to land, the friction to compile pointer-intense C++ code should decrease even more. These are exciting times!
[1]: https://github.com/seanbaxter/shaders#approaching-circle-sha...