Hi, Under fortran, MPI_Win_allocate_shared is called with a window size of zero for some processes. The output pointer is then not valid for these processes (null pointer). Did I understood this wrongly? shouldn't the pointers be contiguous, so that for a zero sized window, the pointer should point to the start of the segment of the next rank? The documentation explicitly specifies "size = 0 is valid".
Attached a small code, where rank=0 allocate a window of size zero. All the other ranks get valid pointers, except rank 0. Best regards, Peter
