我无法解决我的Fortran代码的问题。它编译但在执行期间可靠地死亡（分段错误）。
主程序将我的班级cell_autom实例化为ma。它还将我的类random_pathfinder实例化为pf，并将我的ma实例作为参数传递给它的构造函数：
use ClassCellularAutomata
use ClassRule
use ClassRandomPathfinder
implicit none
class(random_pathfinder), allocatable :: pf
class(cell_autom), allocatable :: ma
integer, parameter :: width = 30
integer, parameter :: T_steps = 3
integer, parameter :: step_dist = 4
double precision, parameter :: goal_score = 0.90
allocate(ma, source = moore_autom(width, width, T_steps))
call ma%rule%generate_random()
call ma%random_seed_field()
allocate(pf, source = random_pathfinder(ma, step_dist, goal_score))
call pf%run_pathfinder()
现在，在pf构造函数语句setup中allocate(inst%autom, source = autom)的构造期间发生了分段错误：
module ClassRandomPathfinder
use ClassCellularAutomata
use ClassRule
implicit none
type random_pathfinder
class(cell_autom), allocatable :: autom
type(rule) :: goal_rule
integer :: step_dist
logical, allocatable :: goal_pattern(:,:)
logical, allocatable :: steps_done(:)
double precision :: current_score, goal_score
integer(kind=4) :: path_length
contains
procedure, pass(this) :: run_pathfinder
end type
interface random_pathfinder
procedure setup
end interface
contains
function setup(autom, step_dist, goal_score) result(inst)
implicit none
class(random_pathfinder), allocatable :: inst
class(cell_autom) :: autom
integer, intent(in) :: step_dist
double precision, intent(in) :: goal_score
integer :: i
! Set init values
allocate(inst%autom, source = autom)
inst%step_dist = step_dist
inst%goal_score = goal_score
! Setup the random pathfinder
! Init goal rule
inst%goal_rule = inst%autom%rule
! Run it once to get the goal pattern
call inst%autom%run()
inst%goal_pattern = inst%autom%get_last_pattern()
! Reset the automaton
call inst%autom%reset_to_last_start()
! change the rule
do i = 1, inst%step_dist
call inst%autom%rule%flip_random_rule_entry()
end do
end function setup
我的第一个想法是责怪分配声明本身或我的autom或cell_autom定义。但在我注释掉这一行（以及其他行）之后，分段错误恰好在下一行中发生inst%分配。所以我想问题出在我的random_pathfinder类或它的构造函数上。
我对Fortran的新手很陌生，并且不知道出了什么问题。也许你们中的一个人看到了一个或几个明显的错误。
我正在使用f08和gfortran编译器。另一个问题是gdb并没有在oop程序中停留在我的geany断点上（是的，我使用了-g标志）。
要完成此操作，请参阅我的cell_autom类型定义：
type cell_autom
! M x N fields, T_steps time steps
integer :: M=0, N=0, T_steps=0
! set true to export an image array every step
logical :: export_every_step = .False., print_every_step = .False.
! field_a and field_b will be iterated and set alternatingly
logical, allocatable :: field_a(:,:), field_b(:,:), start_pattern(:,:)
! image array holds a 0/1 integer representation of a field
integer, allocatable :: image_array(:,:)
! rule holds the update rule
class(rule), allocatable :: rule
! data_dir is the directory where image and info files will be saved
character(len=4) :: data_dir
contains
procedure, pass(this) :: general_init
procedure, pass(this) :: setupField
procedure, pass(this) :: random_seed_field
procedure, pass(this) :: single_random_seed_field
procedure, nopass :: compare_fields
procedure, pass(this) :: reset_fields
procedure, pass(this) :: export_image_array
procedure, nopass :: print_logical_array
procedure, pass(this) :: write_info_file
procedure, pass(this) :: print_and_export_each_step
procedure, pass(this) :: save_rule
procedure, pass(this) :: open_rule
procedure, pass(this) :: run
procedure, pass(this) :: field_iteration
procedure, pass(this) :: get_last_pattern
procedure, pass(this) :: reset_to_last_start
end type cell_autom
! A general Moore automaton
type, extends(cell_autom) :: moore_autom
contains
procedure, pass(this) :: field_iteration => moore_iteration
end type
contains
! Constructor for moore_autom
function init_moore_autom(M, N, T_steps) result(inst)
implicit none
type(moore_autom) :: inst
type(rule) :: moore_rule
integer, intent(in) :: M, N, T_steps
call inst%general_init(M, N, T_steps)
call moore_rule%init_moore()
allocate(inst%rule, source = moore_rule)
end function init_moore_autom