[Bug fortran/78757] New: ICE with function returning a pointer to a character

["jb at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78757

            Bug ID: 78757
           Summary: ICE with function returning a pointer to a character
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jb at gcc dot gnu.org
  Target Milestone: ---

The following testcase causes an ICE when compiling with -O1 on
x86_64-pc-linux-gnu on todays (2016-12-09) trunk:

! Reduced and modified from char_result_8.f90
! { dg-do run }
program main
  implicit none

  character (len = 30), target :: string
  character(len=30), pointer :: s

  s => f4(70_8)

contains

  function f4 (i)
    integer(8) :: i
    character (len = i), pointer :: f4
    f4 => string
  end function f4

end program main


A slightly different way of causing (most likely) the same bug to appear
(compile with "-O1 -fdefault-integer-8"):

! Reduced from char_result_8.f90
! { dg-options "-fdefault-integer-8" }
! { dg-do run }
program main
  implicit none

  character (len = 30), target :: string
  character(len=30), pointer :: s

  s => f4(70)

contains

  function f4 (i)
    integer :: i
    character (len = i), pointer :: f4
    f4 => string
  end function f4

end program main