Dereference null return value in make_shared_object.hpp

[Gaurav Gupta <g.gupta@…>]

Using some static analyzer tool , Boost reports warning messages Dereference null return value.

In codes like: boost::detail::sp_ms_deleter< T > * pd = static_cast<boost::detail::sp_ms_deleter< T > *>( pt._internal_get_untyped_deleter() );

pd is dereference in next line : void * pv = pd->address();

If pd is NULL in above call, dereferencing it may cause crash.

It can be avoided by using: BOOST_ASSERT(!pd);

It is at many places.