That's a reasonable assumption, but it turns out to rarely be the case with WG5/SC22/J3. There are exceptions (like SIND, SINPI, &c.), but most new features in

That's a reasonable assumption, but it turns out to rarely be the case with WG5/SC22/J3. There are exceptions (like SIND, SINPI, &c.), but most new features in Fortran standards are committee inventions without prototypes, reference implementations, or official conformance test suites. This leads to incompatible implementations, and then lack of use in codes that need to be portable. It's a mess, really. I have a test suite of examples of this kind of thing that accumulated during the implementation of flang-new, in which it was a difficult task to figure out what portable Fortran really means in a way that's meaningful to users.