Fabrice Bellard is smart enough that he can probably work directly with obfuscated code without it having to go through a separate translation process. The "obfuscated" source could in fact be the original :)
http://nsl.com/papers/origins.htm
(Arthur Whitney's initial implementation of "J")
The rationale is: To write a J interpreter/compiler you need to know J. If you know J, then J-style C is easy to work with.