[Bug fortran/86033] New: Automated reallocation of empty string array fails with -fcheck=all

["m.diehl at mpie dot de" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86033

            Bug ID: 86033
           Summary: Automated reallocation of empty string array fails
                    with -fcheck=all
           Product: gcc
           Version: 8.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: m.diehl at mpie dot de
  Target Milestone: ---

The following code fails at runtime with
> Fortran runtime error: Different CHARACTER lengths (0/64) in array constructor
if I compile with
> -fcheck=all
in addition to
> gfortran -std=f2008ts

program test

  implicit none
  character(len=64), dimension(:), allocatable :: str64Array
  character(len=64)  :: str64


  allocate(str64Array(0),source=str64) ! empty array

  write(6,*) size(str64Array);  flush(6)    ! gives 0
  write(6,*) len(str64Array(0)); flush(6)   ! gives 64

  str64 ='a'
  str64Array = [str64Array,str64]           ! causes error with -fcheck=all

  write(6,*) size(str64Array);  flush(6)    ! gives 1 if compiled without
-fcheck=all
  write(6,*) len(str64Array(1)); flush(6)   ! gives 64 if compiled without
-fcheck=all

  str64 ='b'
  str64Array = [str64Array,str64]

  write(6,*) size(str64Array);  flush(6)    ! gives 2 if compiled without
-fcheck=all
  write(6,*) len(str64Array(1)); flush(6)   ! gives 64 if compiled without
-fcheck=all
  write(6,*) len(str64Array(2)); flush(6)   ! gives 64 if compiled without
-fcheck=all

  write(6,*) str64Array(1); flush(6)        ! gives a if compiled without
-fcheck=all
  write(6,*) str64Array(2); flush(6)        ! gives b if compiled without
-fcheck=all

end program