[Patch, fortran] PR32665 - allocatable array on lhs deleted while still in use on rhs

[Tobias Burnus]

:REVIEWMAIL:
Paul Richard Thomas wrote:
> (i) An array constructor, used as an argument in the constructor of a
> structure with allocatable components, yielded incorrect bounds for
> the allocatable component.  This manifests itself as memory leaks, bad
> accesses and segfaults at runtime (PR31320).
> (ii)  The dependency between the rhs and lhs, where the lhs appears as
> a reference in its own constructor, led to an ICE because the array
> was deallocated at the start of the assignment.
> Regtested on Cygwin_NT/amd64 - does not break cp2k - OK for trunk?

OK. Thanks for the fix.

Tobias


Side remark: The generated executable leaks memory:

 96 bytes in 1 blocks are definitely lost in loss record 1 of 2
    at 0x4C22D06: malloc (in
/usr/lib64/valgrind/amd64-linux/vgpreload_memcheck.so)
    by 0x40122B: MAIN__ (alloc_comp_assign_2.f90:11)
    by 0x401EEB: main (fmain.c:22)

 96 bytes in 1 blocks are definitely lost in loss record 2 of 2
    at 0x4C22D06: malloc (in
/usr/lib64/valgrind/amd64-linux/vgpreload_memcheck.so)
    by 0x400BCA: MAIN__ (alloc_comp_assign_2.f90:10)
    by 0x401EEB: main (fmain.c:22)


for this stripped down test case:

  type :: a
    integer, allocatable :: i(:)
  end type a
  type :: b
    type (a), allocatable :: at(:)
  end type b
  type(a) :: x(2)
  type(b) :: y(2)
  integer i
  y(1) = b ((/x(1),x(2)/))
  y(2) = b ((/x(2),x(1)/))
  forall (i=1:2) y(i) = b ((/x(i)/))
end