https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99545
--- Comment #6 from Jürgen Reuter <juergen.reuter at desy dot de> ---
Voila, here is a short reproducer:
module commands
implicit none
private
type, abstract :: range_t
integer :: step_mode = 0
integer :: n_step = 0
end type range_t
type, extends (range_t) :: range_int_t
integer :: i_step = 0
end type range_int_t
type, extends (range_t) :: range_real_t
real :: lr_step = 0
end type range_real_t
type :: cmd_scan_t
private
class(range_t), dimension(:), allocatable :: range
contains
procedure :: compile => cmd_scan_compile
end type cmd_scan_t
contains
subroutine cmd_scan_compile (cmd)
class(cmd_scan_t), intent(inout) :: cmd
allocate (range_int_t :: cmd%range (3))
allocate (range_real_t :: cmd%range (3))
end subroutine cmd_scan_compile
end module commands
