Fortran has multiple incompatible implementations and a standard that's supported completely by none of them, and that hasn't maintained 100% forward compatibility across revisions. It'll still be around in the sense that English will be -- there will be a thing by that name -- but it's impossible to say now exactly what it will be, or to write Fortran now that will still work identically without change for the next century. I think C'89 uniprocessor code would stand a better chance.