Fortran: Alternate ENTRY points

[stevewpalmer]

We do not currently support ENTRY in subroutines and functions to allow alternate entry points. The logistics of this are quite complex and this document makes useful reading if we want to go ahead.

The complexity is due to the fact that we need to allow "jumping" into the middle of a subroutine bypassing code before the ENTRY but executing the code that follows.

It is questionable whether this has any real use in modern Fortran so spend some time investigating the use case and the value vs. resources required to implement. I suspect this will be a significant amount of work for little real gain. However since this is an unimplemented real Fortran statement, it needs to be mentioned.