| This patch addresses upstream issues 5331 | |
| <https://svn.boost.org/trac/boost/attachment/ticket/5331> and 6692 | |
| <https://svn.boost.org/trac/boost/attachment/ticket/6692> by removing | |
| the use of the deprecated swp{b} instructions on ARMv6 and ARMv7 | |
| architectures, replacing them with the newer {ld,st}rex. |