[Bug fortran/78737] linking error with deferred, undefined user-defined derived-type I/O

[jvdelisle at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78737

--- Comment #1 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
I cc'ed Paul on this one. Not sure what is going on here, but I will be looking
at it.