add test program for MPI_Waitall with MPI_STATUSES_IGNORE

tests/irecv_isend_waitall_1.f90

@@ -0,0 +1,62 @@
+program irecv_isend_waitall_1
+    use mpi
+    implicit none
+
+    integer, parameter :: N = 4
+    real(8) :: array2d(N,N)
+    integer :: rank, nprocs, ierr
+    integer :: requests(2)
+    integer :: i
+    ! Added variables for verification
+    real(8) :: expected_array(N,N)
+    real(8) :: received_array(N,N)
+
+    call MPI_INIT(ierr)
+    call MPI_COMM_RANK(MPI_COMM_WORLD, rank, ierr)
+    call MPI_COMM_SIZE(MPI_COMM_WORLD, nprocs, ierr)
+
+    if (nprocs < 2) then
+      if (rank == 0) print *, 'This program requires at least 2 processes'
+      call MPI_FINALIZE(ierr)
+      stop
+    endif
+
+    if (rank == 0) then
+      array2d = reshape([(real(i,8), i=1,N*N)], [N,N])
+      print *, 'Rank 0 preparing to send array:'
+      print *, array2d
+      call MPI_ISEND(array2d, N*N, MPI_DOUBLE_PRECISION, 1, 99, &
+                    MPI_COMM_WORLD, requests(1), ierr)
+      ! Store expected array for later verification
+      expected_array = array2d
+    endif
+
+    if (rank == 1) then
+      call MPI_IRECV(array2d, N*N, MPI_DOUBLE_PRECISION, 0, 99, &
+                    MPI_COMM_WORLD, requests(1), ierr)
+
+      print *, 'Rank 1 doing some work before checking receive...'
+    endif
+
+    if (rank == 0 .or. rank == 1) then
+      call MPI_WAITALL(1, requests, MPI_STATUSES_IGNORE, ierr)
+    endif
+
+    if (rank == 1) then
+      print *, 'Rank 1 received array:'
+      print *, array2d
+      ! Store received array for verification
+      received_array = array2d
+    endif
+
+    call MPI_BCAST(received_array, N*N, MPI_DOUBLE_PRECISION, 1, MPI_COMM_WORLD, ierr)
+    ! Ensure rank 0 has the expected array broadcast to all ranks
+    if (rank /= 0) expected_array = reshape([(real(i,8), i=1,N*N)], [N,N])
+
+    if (any(expected_array /= received_array)) then
+      print *, 'Rank ', rank, ': Verification failed - arrays do not match'
+      error stop 'MPI communication verification failed'
+    endif
+
+    call MPI_FINALIZE(ierr)
+end program