Rust parser accepting subset of C/C++

Maybe the rust community may not like this but a rustc with the a modified parser that accept a subset of C/C++ could help with extra compile time checks to a good subset of C/C++ as an auxiliary tool, I found this project/hn submission that uses macros to accept a Java like syntax https://news.ycombinator.com/item?id=17734648 that is interesting but due to using macros is a bit limited.

Does anyone know any similar project preferable with a modified parser that allow a more natural C/C++ syntax ?

In theory even with the different basic assumption of pass by value versus move by default, I believe that's possible to achieve an interesting result.