Question

我已经实现了一个用Fortran编写的通用链表（genII.f90） http://fortranwiki.org/fortran/show/Linked+list。

我测试它并且一切正常，除了LI_Remove_Head函数似乎没有释放内存的事实。

我在原始模块中添加了函数LI_Destruct（见下文），同样的结果是它没有释放内存。

SUBROUTINE LI_Destruct(List)  
implicit none
TYPE(List_Type),INTENT(INOUT),TARGET :: List
TYPE(Link_Ptr_Type) :: Link_current, Link_next

Link_next%P =>List%Head%next


do while (associated(Link_next%P))
    Link_current%P => Link_next%P

    Link_next%P => Link_next%P%next
    deallocate(Link_current%P)
end do
end subroutine LI_destruct

我当然想念一些，所以我的问题是两个： 1-代码中是否有错误？出于什么原因，“deallocate”没有清空记忆？

2-它是否更好，几乎是标准的fortran通用链表？

我添加了下面用于进行测试的简单代码：

PROGRAM test_list

! Defines data and other list(s) and arrays for particles. 

USE Generic_List, ONLY : Link_Ptr_Type,Link_Type,List_Type
USE Generic_List, ONLY : LI_Init_List,LI_Add_To_Head,LI_Add_To_Tail,LI_Get_Head,&
     LI_Remove_Head,LI_Get_Next,LI_Associated,LI_Get_Len, LI_destruct

IMPLICIT NONE

TYPE:: Particle_data
    REAL, dimension(2)   :: pos       !! Coordinate dimensionali 
END TYPE Particle_data 

! Definition of the types necessary for the list
TYPE Particle_Node
  TYPE(Link_Type) :: Link
  TYPE(Particle_data), pointer :: Data  
END TYPE Particle_Node

TYPE Particle_Node_ptr
  TYPE(Particle_Node), pointer :: P
END TYPE Particle_Node_ptr

! Create array of lists in order to allow classify the particles
TYPE(List_Type), allocatable      :: ao_Particle_List(:)
TYPE(Link_Ptr_Type)  :: Link
TYPE(Particle_Node_ptr)  :: Particle_elem

!-------------------------------------------------------------!
!-------------------------------------------------------------!

INTEGER, parameter :: Npart_test = 1000000  ! , nPart
INTEGER :: i,iter,j,item,nBuffer
REAL :: pos(2)

    nBuffer = 5

    IF (ALLOCATED(ao_Particle_List)) DEALLOCATE(ao_Particle_List)
    ALLOCATE(ao_Particle_List(0:nBuffer))  

    ! Init list used for temporary construction
    DO iter=0,nBuffer
        CALL LI_Init_List(ao_Particle_List(iter))
    ENDDO

    DO j=1,NBuffer
        DO i=1,Npart_test
            pos(1)=i*1.0;  pos(2)=j*i

            ALLOCATE(Particle_elem%P); ALLOCATE(Particle_elem%P%Data)   ! Allocate data before store
            Particle_elem%P%Data%pos = pos

            ! Elem is treated and should be put at head of the list ao_Particle_List(item)
            item=j
            Link = TRANSFER(Particle_elem,Link); CALL LI_Add_To_Head(Link,ao_Particle_List(item)) ! STORAGE
        END DO
    END DO

    WRITE(*,*) "List is full, see RAM"; READ(*,*)


    ! Write(*,*) "Destruct list"
    DO iter=0,nBuffer
        CALL LI_Destruct(ao_Particle_List(iter))  
    ENDDO

    IF (ALLOCATED(ao_Particle_List)) DEALLOCATE(ao_Particle_List)
    WRITE(*,*) "List is empty, see RAM";     READ(*,*)

END PROGRAM

感谢所有人，约翰

Answer 1

好的问题解决了。由于存在传输操作，似乎无法在LI_DESTRUCT函数中完成数据。

解除分配链表的正确方法是（与fortran wiki中的示例略有不同）：

DO
    Link = LI_Remove_Head(ao_Particle_List)
    IF(.NOT.LI_Associated(Link))EXIT
    User = TRANSFER(Link,User)
!~                 WRITE(6,*)User%P%Data%Index,User%P%Data%User_Stuff
    DEALLOCATE(User%P%Data)
    DEALLOCATE(User%P)
ENDDO

解除分配Fortran链表时出现内存故障，

1 个答案: