atomic: fix example code

patch by gregor jasny

svn path=/trunk/libs/atomic/; revision=82361
atomic: uclibc doesn't seem to have intptr_t

fixes #7979

svn path=/trunk/boost/atomic/; revision=82754
atomic: adapt for constexpr and noexcept

Signed-off-by: Tim Blechmann <tim@klingt.org>

svn path=/trunk/boost/atomic/; revision=82870
Atomic: fixing Windows compilation problem

svn path=/trunk/boost/atomic/; revision=82942
Atomic: fix some minor issues.

svn path=/trunk/boost/atomic/; revision=82947
1. Fixed compilation with MSVC 2003.
2. Fixed incorrect reinterpret_casts in constexpr constructors that could result in buffer overruns. The initializing constructors for non-integral atomics are not constexpr yet because memcpy must be used inside.
3. Made atomic_flag default constructors constexpr. This is not by the standard but we do not implement ATOMIC_FLAG_INIT yet, so the default constructor is needed and it should be constexpr when possible.
4. Fixed a few syntax errors and cleaned up the code a bit.
5. Moved operator value_type() to the interface class in order not to duplicate it in base_atomic specializations.
6. The return type of operator=() changed to follow the standard.

svn path=/trunk/boost/atomic/; revision=83096
Fixed typo in the comment.

svn path=/trunk/boost/atomic/; revision=83097
Fixed typo.

svn path=/trunk/boost/atomic/; revision=83098
Added missing constexpr/noexcept.

svn path=/trunk/boost/atomic/; revision=83099