A bus error occurs in sm OSC under the following conditions.
- sparc64 or any other architectures which need strict alignment.
- `MPI_WIN_POST` or `MPI_WIN_START` is called for a window created
by sm OSC.
- The communicator size is odd and greater than 3.
The lines 283-285 in current `ompi/mca/osc/sm/osc_sm_component.c` has
the following code.
```c
module->global_state = (ompi_osc_sm_global_state_t *) (module->segment_base);
module->node_states = (ompi_osc_sm_node_state_t *) (module->global_state + 1);
module->posts[0] = (uint64_t *) (module->node_states + comm_size);
```
The size of `ompi_osc_sm_node_state_t` is multiples of 4 but not
multiples of 8. So if `comm_size` is odd, `module->posts[0]` does
not aligned to 8. This causes a bus error when accessing
`module->posts[i][j]`.
This patch fixes the alignment of `module->posts[0]` by setting
`module->posts[0]` first.