This commit add the following Fortran named constants which are
defined in the MPI standard but are missing in Open MPI.
- `MPI_LONG_LONG` (defined as a synonym of `MPI_LONG_LONG_INT`)
- `MPI_CXX_FLOAT_COMPLEX`
- `MPI_C_BOOL`
And this commit also changes the value of the following Fortran
named constant for consistency.
- `MPI_C_COMPLEX`
`(MPI_C_FLOAT_COMPLEX` is defined as a synonym of this)
Each needs a different solution described below.
For `MPI_LONG_LONG`:
The value of `MPI_LONG_LONG` is defined to have a same value
as `MPI_LONG_LONG_INT` because of the following reasons.
1. It is defined as a synonym of `MPI_LONG_LONG_INT` in
the MPI standard.
2. `MPI_LONG_LONG_INT` and `MPI_LONG_LONG` has a same value
for C in `mpi.h`.
3. `ompi_mpi_long_long` is not defined in
`ompi/datatype/ompi_datatype_module.c`.
For `MPI_CXX_FLOAT_COMPLEX`:
Existing `MPI_CXX_COMPLEX` is replaced with `MPI_CXX_FLOAT_COMPLEX`
bacause `MPI_CXX_FLOAT_COMPLEX` is the right name defined in MPI-3.1
and `MPI_CXX_COMPLEX` is not defined in MPI-3.1 (nor older).
But for compatibility, `MPI_CXX_COMPLEX` is treated as a synonym
of `MPI_CXX_FLOAT_COMPLEX` on Open MPI.
For `MPI_C_BOOL`:
`MPI_C_BOOL` is newly added. The value which `MPI_C_COMPLEX` had
used (68) is assinged for it because the value becomes no longer
in use (described later) and it is a suited position as a datatype
added on MPI-2.2.
For `MPI_C_COMPLEX`:
Existing `MPI_C_FLOAT_COMPLEX` is replaced with `MPI_C_COMPLEX`
and `MPI_C_FLOAT_COMPLEX` is changed to have the same value.
In other words, make `MPI_C_COMPLEX` the canonical name and
make `MPI_C_FLOAT_COMPLEX` an alias of it.
This is bacause the relation of these datatypes is same as
the relation of `MPI_LONG_LONG_INT` and `MPI_LONG_LONG`, and
`MPI_LONG_LONG_INT` and `MPI_LONG_LONG` are implemented like that.
But in the datatype engine, we use `ompi_mpi_c_float_complex`
instead of `ompi_mpi_c_complex` as a variable name to keep
the consistency with the other similar types such as
`ompi_mpi_c_double_complex` (see George's comment in open-mpi/ompi#1927).
We don't delete `ompi_mpi_c_complex` now because it is used in
some other places in Open MPI code. It may be cleand up in the future.
In addition, `MPI_CXX_COMPLEX`, which was defined only in the Open MPI
Fortran binding, is added to `mpi.h` for the C binding.
This commit breaks binary compatibility of Fortran `MPI_C_COMPLEX`.
When this commit is merged into v2.x branch, the change of
`MPI_C_COMPLEX` should be excluded.