Fortress, a new language designed specifically for high-performance computing (HPC), has been released on SunSource under the BSD language. The preliminary interpreter is based on the JVM. Fortress is intended as a modern day replacement for Fortran.
Fortress was created as part of Sun's work on the DARPA HPCS program. Sun has since been knocked out of the program, but Guy Steele has continued work on the language. X10 from IBM and Chapel from Cray are also HPC languages under development.
While the Fortress interpreter is currently based on the JVM, it is a new language and has not been tied to any legacy language syntax or semantics. To tailor itself to the HPC programming, Fortress supports mathematical notation and static checking of physical units and dimensions. Also, many of the core language constructs are parallel by default, helping to tailor it to multi-core systems. There are signs that Fortress may not stay on the JVM, but may eventually have its own virtual machine. For instance, Fortress has a different memory model than Java and, according to the latest language specification (still in alpha), it will support some form of software transactional memory (STM).
Fortress is currently only an interpreted language, but the intention is to make an optimizing compiler available at some point in the future.