[plt-scheme] LLVM

A couple of years ago there was some talk about using the LLVM
compiler infrastructure for code generation:

http://www.cs.brown.edu/pipermail/plt-scheme/2006-August/014363.html

There were a few shortcomings brought up in that thread, and it was
indicated that if they were addressed LLVM should be re-evaluated, to
provide for low-level optimizations and whole-program native
compilation, among other benefits. Does anyone know if the problems
(tail calls, etc.) are still an issue? If LLVM were considered for
code generation, would its garbage collection utilities[1] simplify
the development of an incremental garbage collector for PLT-Scheme?

    Henk Boom

[1] http://llvm.org/docs/GarbageCollection.html