I think you could write some sort of simple language that would get expanded into BF.

e.g.

  +6 -> ++++++

You could compile to brainfuck, treating it as a very simple virtual machine. It's just simplified to the point of being incredibly inefficient, like factoring Church-encoded numbers with Prolog's unification, rather than using its built-in mathematical primitives.

(Whether the bf compiler was actually written or just generated by compiling to bf is neither here nor there.)

in fact, there is work on a gcc-backend which outputs brainfuck (name's gcc-bf)