https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86328
Bug ID: 86328
Summary: Runtime segfault reading an allocatable class(*)
object in allocate statements
Product: gcc
Version: 8.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: mscfd at gmx dot net
Target Milestone: ---
The following code leads to a runtime segfault:
program ptr_alloc
type :: t
class(*), allocatable :: val
end type t
type :: list
type(t), dimension(:), pointer :: ll
integer :: cnt
end type list
integer :: i
type(list) :: a
allocate(a%ll(1:1))
do i = 1,10
print *,i
a%cnt = i
allocate(a%ll(i)%val, source=i)
call rrr(a)
end do
contains
subroutine rrr(a)
type(list) :: a
integer :: s, i
type(t), dimension(:), pointer :: mm
s = ubound(a%ll,1) + 1
allocate(mm(1:s))
do i = 1, s-1
if (allocated(a%ll(i)%val)) then
allocate(mm(i)%val, source=a%ll(i)%val)
! allocate(mm(i)%val, mold=a%ll(i)%val)
! mm(i)%val = a%ll(i)%val
deallocate(a%ll(i)%val)
end if
end do
deallocate(a%ll)
a%ll => mm
end subroutine rrr
end program ptr_alloc
Using the commented mold and assignment version also leads to a segfault. Using
allocation on assignment (just the commented assignment) works, but then the
deallocation statement fails with a segfault.
valgrind reports an "Invalid read of size 8".
