PR 61281: Memory corruption on assigning a polymorphic variable to a non-polymorphic one

[Damian Rouson]

Gfortran developers,

I just submitted the following as PR 61281:

The code below demonstrates a bug isolated from code from my collaborator Rob Rosenberg of the Naval Research Laboratory.  The code exhibits an apparent memory corruption issue with gfortran 4.9 dated 20140416.  Gfortran 4.8.2 rejects the code with the message below.

Damian


$ cat rob.f90 
 type employees
   character(3) :: name="rob"
 end type 
 type companies
   type(employees) :: list
 end type 
 type(companies) :: nrl
 print *,nrl%list
 call map
 print *,nrl%list
contains
 type (employees) function give_raise(e) 
   class(employees) :: e ! Switch to "type" to hide bug
   give_raise=e
 end function 
 subroutine map() 
   nrl%list=give_raise(nrl%list)
 end subroutine
end 
$ gfortran rob.f90 
$ ./a.out
rob
8??
$ gfortran --version
GNU Fortran (MacPorts gcc49 4.9-20140416_0) 4.9.0 20140416 (prerelease)
Copyright (C) 2014 Free Software Foundation, Inc.
$ sudo port select --set gcc mp-gcc48
Selecting 'mp-gcc48' for 'gcc' succeeded. 'mp-gcc48' is now active.
$ gfortran rob.f90 
rob.f90:14.15:

    give_raise=e
               1
Error: Can't convert CLASS(employees) to TYPE(employees) at (1)
localhost:Desktop rouson$ gfortran --version
GNU Fortran (MacPorts gcc48 4.8.2_0) 4.8.2