I think 3.5 minutes down to less than 15 seconds for a recent kernel is probably possible. On the other hand, tcc generates code which runs 3.5x slower, so you'd have to be doing a lot of compiling and not much running for it to save any time. JIT'ing the kernel is a fun exercise, nonetheless.
http://lists.nongnu.org/archive/html/tinycc-devel/2013-02/ms...
I think 3.5 minutes down to less than 15 seconds for a recent kernel is probably possible. On the other hand, tcc generates code which runs 3.5x slower, so you'd have to be doing a lot of compiling and not much running for it to save any time. JIT'ing the kernel is a fun exercise, nonetheless.