Some MPI procedures use address arguments that represent an absolute address in the calling program, or relative displacement arguments that represent differences of two absolute addresses. The datatype of such arguments is MPI_Aint in C and INTEGER (KIND= MPI_ADDRESS_KIND) in Fortran. These types must have the same width and encode address values in the same manner such that address values in one language may be passed directly to another language without conversion. There is the MPI constant MPI_BOTTOM to indicate the start of the address range. For retrieving absolute addresses or any calculation with absolute addresses, one should use the routines and functions provided in Section Address and Size Functions . Section Correct Use of Addresses provides additional rules for the correct use of absolute addresses. For expressions with relative displacements or other usage without absolute addresses, intrinsic operators (e.g., +, -, *) can be used.