我在定义 mpi_type_contiguous 和稍后使用 mpi_gatherv 时遇到了一个奇怪的问题。类型定义为：
type glist
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!uncomment line below for int version:
! integer :: iref , biref
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
real(8) :: rvar
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!uncomment line below for buggy version:
integer :: ciref
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
end type glist
现在的代码不起作用。如果我要发表评论integer :: ciref，它会起作用。如果我real(8) :: rvar改为注释并取消注释其他两个整数，情况也是如此integer :: iref, biref。
这意味着错误取决于数据类型的大小，但前提是其中有 a real(8)。如果我有一个real(8)和两个，int那么它会再次起作用。
该代码设计为使用 3 个线程（！）运行。我用 openmpi 和 gfortran (mpif90) 运行它。没有特殊的编译标志和使用mpirun -np 3 filename. 如果有人可以用 mpich 运行它或用 ifort 或任何有趣的东西编译它，以便找出问题出在哪里。
- - 编辑 - -
Platinummonkey 建议在下面使用mpi_type_struct，但它仍然不起作用。如果我sizeof(glist)像上面那样使用 glist，我会得到 16 而不是 12 作为答案。
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在此先感谢您的帮助。
完整的代码是（不要担心其中一些可以忽略）
module mod_glist
type glist
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!uncomment line below for int version:
! integer :: iref , biref
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
real(8) :: rvar
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!uncomment line below for buggy version:
integer :: ciref
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
end type glist
contains
subroutine sof_glist(sof)
implicit none
integer, intent(out) :: sof
type(glist) :: dum
integer :: val
val = 0
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!uncomment line below for int version:
! val = kind(dum%iref) + kind(dum%biref)
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
val = val + kind(dum%rvar)
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!uncomment line below for buggy version:
val = val + kind(dum%ciref)
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
sof = val/kind(0)
write(*,*) 'Size in bytes, integers: ', sof, val
end subroutine
end module mod_glist
program test_mpi_gatherv
use mpi
use mod_glist
implicit none
integer :: err, np, tp, nglout, i, j, nglin, sofgl, mpi_type_glist
type(glist), dimension(:), allocatable :: gl, glcom, glsave
integer , dimension(:), allocatable :: glsize, nglinv, nglinp
integer(kind=mpi_address_kind) :: ii, ij
call mpi_init(err)
call mpi_comm_size(mpi_comm_world, np, err)
call mpi_comm_rank(mpi_comm_world, tp, err)
tp = tp + 1
call sof_glist(sofgl)
call mpi_type_contiguous(sofgl, mpi_integer, mpi_type_glist, err)
call mpi_type_commit(mpi_type_glist, err)
call mpi_type_get_extent(mpi_type_glist, ii, ij, err)
write(*,*) 'extend: ', ii, ij
allocate(glsize(np), nglinv(np), nglinp(np))
glsize(1) = 5
glsize(2) = 4
glsize(3) = 3
glsize(4:np) = 0
allocate(gl(glsize(tp)))
j = 1
do i = 1,tp-1
j = j+glsize(i)
enddo
do i = 1,glsize(tp)
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!uncomment line below for int version:
! gl(i)%iref = j
! gl(i)%biref = -j
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
gl(i)%rvar = real(j,8)
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!uncomment line below for buggy version:
gl(i)%ciref = -j*10
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
j = j+1
enddo
do i=1,np ! setting up stuff can be ignored
if(i.eq.1)then
if(tp.eq.i)then
nglinv(1) = 0
nglinv(2) = 2
nglinv(3) = 3
nglinp(1) = 0
nglinp(2) = nglinv(1) + nglinp(1)
nglinp(3) = nglinv(2) + nglinp(2)
nglin = nglinv(1) + nglinv(2) + nglinv(3)
allocate(glcom(nglin))
nglout = 0
else
if(tp.eq.2)then
nglout = 2
allocate(glcom(nglout))
glcom(1) = gl(1)
glcom(2) = gl(3)
elseif(tp.eq.3)then
nglout = 3
allocate(glcom(nglout))
glcom(1) = gl(1)
glcom(2) = gl(2)
glcom(3) = gl(3)
endif
endif
elseif(i.eq.2)then
if(tp.eq.i)then
nglinv(1) = 3
nglinv(2) = 0
nglinv(3) = 2
nglinp(1) = 0
nglinp(2) = nglinv(1) + nglinp(1)
nglinp(3) = nglinv(2) + nglinp(2)
nglin = nglinv(1) + nglinv(2) + nglinv(3)
allocate(glcom(nglin))
nglout = 0
else
if(tp.eq.1)then
nglout = 3
allocate(glcom(nglout))
glcom(1) = gl(2)
glcom(2) = gl(4)
glcom(3) = gl(5)
elseif(tp.eq.3)then
nglout = 2
allocate(glcom(nglout))
glcom(1) = gl(2)
glcom(2) = gl(3)
endif
endif
elseif(i.eq.3)then
if(tp.eq.i)then
nglinv(1) = 0
nglinv(2) = 2
nglinv(3) = 0
nglinp(1) = 0
nglinp(2) = nglinv(1) + nglinp(1)
nglinp(3) = nglinv(2) + nglinp(2)
nglin = nglinv(1) + nglinv(2) + nglinv(3)
allocate(glcom(nglin))
nglout = 0
else
if(tp.eq.1)then
nglout = 0
allocate(glcom(nglout))
elseif(tp.eq.2)then
nglout = 2
allocate(glcom(nglout))
glcom(1) = gl(1)
glcom(2) = gl(4)
endif
endif
endif ! end of setting up stuff
if(i.eq.tp) allocate(glsave(nglin))
! debug output
call mpi_barrier(mpi_comm_world, err)
write(*,*) i, tp, nglout, nglin
call mpi_barrier(mpi_comm_world, err)
if(i.eq.tp) write(*,*) i, nglinv, nglinp
call mpi_barrier(mpi_comm_world, err)
! end debug output
call mpi_gatherv(glcom, nglout, mpi_type_glist, glsave, nglinv, nglinp, mpi_type_glist, i-1, mpi_comm_world, err)
if(allocated(glcom)) deallocate(glcom)
enddo
! debug output
call mpi_barrier(mpi_comm_world, err)
do i = 1,nglin
write(*,*) tp, i, glsave(i)
enddo
! end debug output
call mpi_finalize(err)
end program