A number of years ago I implemented xoshiro256** for the GFortran compiler. Previously it used Marsaglia's KISS generator, which wasn't bad but perhaps no longe

A number of years ago I implemented xoshiro256** for the GFortran compiler. Previously it used Marsaglia's KISS generator, which wasn't bad but perhaps no longer state of the art on the TESTU1 etc. tests. Additionally, xoshiro256** can be used in parallel by multiple threads; that took a bit of clever hacking to work around the limitations of the Fortran intrinsics API.