Lambda the Ultimate

I will always have a soft spot in my (otherwise cold, desolate, inchoate) heart for SML.

Their main page is unreachable for me just now (you can get e.g. the google cached version of it still if you like), but their last announcement was in April of this year (2014) so I hope the project is still alive.

SML# is an extension of Standard ML with practically important features, including record polymorphism, seamless interoperability with C, true separate compilation and linking, and native multithread support on multicore CPUs.

The most notable change in SML# version 2 is that the SML# compiler now works with the LLVM Compiler Infrastructure. The new SML# compiler compiles SML# code including all of the above features to LLVM IR code and produces native code through LLVM. More than half of compilation phases and library modules has been rewritten for the LLVM support. These changes also greatly speed up the compilation processes.

The major difficulties we have overcome in SML#-LLVM codegen is the treatment of polymorphism and separate compilation with SML#'s native ("unboxed") data representations. This aspect requires both a certain amount of additional type theoretical development specific to LLVM target and careful constructions of LLVM codegen. We hope to report this somewhere.