[Bug libfortran/30617] Implement a run time diagnostic for invalid recursive I/O

[jvdelisle at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=30617

--- Comment #48 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
See my comment here:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123106#c5

I think this runtime error will be straight forward.