* include/bits/shared_ptr_base.h (__shared_ptr::operator->): Change
	_GLIBCXX_DEBUG_ASSERT to _GLIBCXX_DEBUG_PEDASSERT.
	* include/bits/unique_ptr.h (unique_ptr::operator->): Likewise.
	* testsuite/20_util/shared_ptr/observers/get.cc: Test operator-> on
	empty shared_ptr.

From-SVN: r227524