[Bug fortran/126517] Assigning an unallocated allocatable function result array to an allocatable causes segmentation fault

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126517

--- Comment #5 from Mikael Morin <mikael at gcc dot gnu.org> ---
(In reply to Steve Kargl from comment #3)
> Your example suggests that gfortran should issue an error/warning
> about an unallocated function result.  Given the complexity of 
> the allocation/deallocation code, this may be a difficult thing to
> get right.

Thomas' recent -Wunused-vars warning doesn't catch it.
I've opened PR126530 for that.