[NFC] [libcxx] Remove shared_ptr's no-rvalue unique_ptr converting constructor.

[zoecarver]

Summary

All compilers supported by libc++ have rvalues in C++03 mode so, there is no need for this non-rvalue overload.

[zoecarver]

This passes all memory tests in C++03, C++11, and C++2a mode.

libcxx/include/memory

template<class _Yp>
         shared_ptr(auto_ptr<_Yp>&& __r,
                    typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
 #else
     template<class _Yp>
         shared_ptr(auto_ptr<_Yp> __r,
                    typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
 #endif
 #endif
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
     template <class _Yp, class _Dp>
         shared_ptr(unique_ptr<_Yp, _Dp>&&,
                    typename enable_if
                    <
                        !is_lvalue_reference<_Dp>::value &&
                        !is_array<_Yp>::value &&
                        is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
                        __nat
                    >::type = __nat());
     template <class _Yp, class _Dp>
         shared_ptr(unique_ptr<_Yp, _Dp>&&,
                    typename enable_if
                    <
                        is_lvalue_reference<_Dp>::value &&
                        !is_array<_Yp>::value &&
                        is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
                        __nat
                    >::type = __nat());
-#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-    template <class _Yp, class _Dp>
-        shared_ptr(unique_ptr<_Yp, _Dp>,
-                   typename enable_if
-                   <
-                       !is_lvalue_reference<_Dp>::value &&
-                       !is_array<_Yp>::value &&
-                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
-                       __nat
-                   >::type = __nat());
-    template <class _Yp, class _Dp>
-        shared_ptr(unique_ptr<_Yp, _Dp>,
-                   typename enable_if
-                   <
-                       is_lvalue_reference<_Dp>::value &&
-                       !is_array<_Yp>::value &&
-                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
-                       __nat
-                   >::type = __nat());
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
     ~shared_ptr();
 
     _LIBCPP_INLINE_VISIBILITY
     shared_ptr& operator=(const shared_ptr& __r) _NOEXCEPT;
     template<class _Yp>
         typename enable_if
         <
#endif
     __cntrl_ = new _CntrlBlk(__r.get(), default_delete<_Yp>(), allocator<_Yp>());
     __enable_weak_this(__r.get(), __r.get());
     __r.release();
 }
 #endif
 
 template<class _Tp>
 template <class _Yp, class _Dp>
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
 shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
-#else
-shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
-#endif
                             typename enable_if
                             <
                                 !is_lvalue_reference<_Dp>::value &&
                                 !is_array<_Yp>::value &&
                                 is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
                                 __nat
                             >::type)
     : __ptr_(__r.get())
#endif
         __cntrl_ = new _CntrlBlk(__r.get(), __r.get_deleter(), _AllocT());
         __enable_weak_this(__r.get(), __r.get());
     }
     __r.release();
 }
 
 template<class _Tp>
 template <class _Yp, class _Dp>
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
 shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
-#else
-shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
-#endif
                             typename enable_if
                             <
                                 is_lvalue_reference<_Dp>::value &&
                                 !is_array<_Yp>::value &&
                                 is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
                                 __nat
                             >::type)
     : __ptr_(__r.get())

libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/unique_ptr.pass.cpp

assert(A::count == 0);
         globalMemCounter.throw_after = 0;
         try
         {
             std::shared_ptr<B> p(std::move(ptr));
             assert(false);
         }
         catch (...)
         {
-#if TEST_STD_VER >= 11
             assert(A::count == 1);
             assert(B::count == 1);
             assert(ptr.get() == raw_ptr);
-#else
-            (void) raw_ptr; // silence 'unused variable' warning
-            assert(A::count == 0);
-            assert(B::count == 0);
-            assert(ptr.get() == 0);
-#endif // TEST_STD_VER >= 11
         }
     }
 #endif
 
 #if TEST_STD_VER > 14
     {
       std::unique_ptr<int> ptr;
       std::shared_ptr<int> p(std::move(ptr));