There is an exciting new JIT engine under construction at the moment
by Vladimir Makarov from RedHat - https://github.com/vnmakarov/mir.
This project is exciting because it aims to deliver a JIT engine that
achieves 70% of the performance of gcc/clang while remaining a very
small library. The library is so small that it takes only a second or
two to build.
Incredibly, Vladimir has also provided a C11 front-end to the JIT,
including a built in C-preprocessor.
I am really pleased to say that Ravi supports this backend already;
although official releases won't be available until the JIT library