From 39601efae4bf15a63618b6e634d3f4fc93e6566b Mon Sep 17 00:00:00 2001 From: Nikolas Klauser Date: Fri, 19 Jul 2024 09:28:34 +0200 Subject: [PATCH] [libc++] Take the ABI break for unconditionally --- libcxx/include/__configuration/abi.h | 2 - libcxx/include/list | 134 ++++++++++++--------------- 2 files changed, 61 insertions(+), 75 deletions(-) diff --git a/libcxx/include/__configuration/abi.h b/libcxx/include/__configuration/abi.h index cbde7887becf1e..01e903417d9e88 100644 --- a/libcxx/include/__configuration/abi.h +++ b/libcxx/include/__configuration/abi.h @@ -24,8 +24,6 @@ # define _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT // Fix deque iterator type in order to support incomplete types. # define _LIBCPP_ABI_INCOMPLETE_TYPES_IN_DEQUE -// Fix undefined behavior in how std::list stores its linked nodes. -# define _LIBCPP_ABI_LIST_REMOVE_NODE_POINTER_UB // Fix undefined behavior in how __tree stores its end and parent nodes. # define _LIBCPP_ABI_TREE_REMOVE_NODE_POINTER_UB // Fix undefined behavior in how __hash_table stores its pointer types. diff --git a/libcxx/include/list b/libcxx/include/list index 929c84de7be449..69651260f52059 100644 --- a/libcxx/include/list +++ b/libcxx/include/list @@ -271,19 +271,10 @@ struct __list_node_pointer_traits { typedef __rebind_pointer_t<_VoidPtr, __list_node<_Tp, _VoidPtr> > __node_pointer; typedef __rebind_pointer_t<_VoidPtr, __list_node_base<_Tp, _VoidPtr> > __base_pointer; -#if defined(_LIBCPP_ABI_LIST_REMOVE_NODE_POINTER_UB) - typedef __base_pointer __link_pointer; -#else - typedef __conditional_t::value, __base_pointer, __node_pointer> __link_pointer; -#endif - - typedef __conditional_t::value, __base_pointer, __node_pointer> - __non_link_pointer; + static _LIBCPP_HIDE_FROM_ABI __base_pointer __unsafe_link_pointer_cast(__base_pointer __p) { return __p; } - static _LIBCPP_HIDE_FROM_ABI __link_pointer __unsafe_link_pointer_cast(__link_pointer __p) { return __p; } - - static _LIBCPP_HIDE_FROM_ABI __link_pointer __unsafe_link_pointer_cast(__non_link_pointer __p) { - return static_cast<__link_pointer>(static_cast<_VoidPtr>(__p)); + static _LIBCPP_HIDE_FROM_ABI __base_pointer __unsafe_link_pointer_cast(__node_pointer __p) { + return static_cast<__base_pointer>(static_cast<_VoidPtr>(__p)); } }; @@ -292,16 +283,13 @@ struct __list_node_base { typedef __list_node_pointer_traits<_Tp, _VoidPtr> _NodeTraits; typedef typename _NodeTraits::__node_pointer __node_pointer; typedef typename _NodeTraits::__base_pointer __base_pointer; - typedef typename _NodeTraits::__link_pointer __link_pointer; - __link_pointer __prev_; - __link_pointer __next_; + __base_pointer __prev_; + __base_pointer __next_; - _LIBCPP_HIDE_FROM_ABI __list_node_base() - : __prev_(_NodeTraits::__unsafe_link_pointer_cast(__self())), - __next_(_NodeTraits::__unsafe_link_pointer_cast(__self())) {} + _LIBCPP_HIDE_FROM_ABI __list_node_base() : __prev_(__self()), __next_(__self()) {} - _LIBCPP_HIDE_FROM_ABI explicit __list_node_base(__link_pointer __prev, __link_pointer __next) + _LIBCPP_HIDE_FROM_ABI explicit __list_node_base(__base_pointer __prev, __base_pointer __next) : __prev_(__prev), __next_(__next) {} _LIBCPP_HIDE_FROM_ABI __base_pointer __self() { return pointer_traits<__base_pointer>::pointer_to(*this); } @@ -332,12 +320,12 @@ public: #endif typedef __list_node_base<_Tp, _VoidPtr> __base; - typedef typename __base::__link_pointer __link_pointer; + typedef typename __base::__base_pointer __base_pointer; - _LIBCPP_HIDE_FROM_ABI explicit __list_node(__link_pointer __prev, __link_pointer __next) : __base(__prev, __next) {} + _LIBCPP_HIDE_FROM_ABI explicit __list_node(__base_pointer __prev, __base_pointer __next) : __base(__prev, __next) {} _LIBCPP_HIDE_FROM_ABI ~__list_node() {} - _LIBCPP_HIDE_FROM_ABI __link_pointer __as_link() { return static_cast<__link_pointer>(__base::__self()); } + _LIBCPP_HIDE_FROM_ABI __base_pointer __as_link() { return __base::__self(); } }; template > @@ -350,11 +338,11 @@ class _LIBCPP_TEMPLATE_VIS __list_const_iterator; template class _LIBCPP_TEMPLATE_VIS __list_iterator { typedef __list_node_pointer_traits<_Tp, _VoidPtr> _NodeTraits; - typedef typename _NodeTraits::__link_pointer __link_pointer; + typedef typename _NodeTraits::__base_pointer __base_pointer; - __link_pointer __ptr_; + __base_pointer __ptr_; - _LIBCPP_HIDE_FROM_ABI explicit __list_iterator(__link_pointer __p) _NOEXCEPT : __ptr_(__p) {} + _LIBCPP_HIDE_FROM_ABI explicit __list_iterator(__base_pointer __p) _NOEXCEPT : __ptr_(__p) {} template friend class list; @@ -408,11 +396,11 @@ public: template class _LIBCPP_TEMPLATE_VIS __list_const_iterator { typedef __list_node_pointer_traits<_Tp, _VoidPtr> _NodeTraits; - typedef typename _NodeTraits::__link_pointer __link_pointer; + typedef typename _NodeTraits::__base_pointer __base_pointer; - __link_pointer __ptr_; + __base_pointer __ptr_; - _LIBCPP_HIDE_FROM_ABI explicit __list_const_iterator(__link_pointer __p) _NOEXCEPT : __ptr_(__p) {} + _LIBCPP_HIDE_FROM_ABI explicit __list_const_iterator(__base_pointer __p) _NOEXCEPT : __ptr_(__p) {} template friend class list; @@ -485,8 +473,8 @@ protected: typedef typename __node_alloc_traits::pointer __node_pointer; typedef typename __node_alloc_traits::pointer __node_const_pointer; typedef __list_node_pointer_traits __node_pointer_traits; - typedef typename __node_pointer_traits::__link_pointer __link_pointer; - typedef __link_pointer __link_const_pointer; + typedef typename __node_pointer_traits::__base_pointer __base_pointer; + typedef __base_pointer __link_const_pointer; typedef typename __alloc_traits::pointer pointer; typedef typename __alloc_traits::const_pointer const_pointer; typedef typename __alloc_traits::difference_type difference_type; @@ -499,7 +487,7 @@ protected: __node_base __end_; __compressed_pair __size_alloc_; - _LIBCPP_HIDE_FROM_ABI __link_pointer __end_as_link() const _NOEXCEPT { + _LIBCPP_HIDE_FROM_ABI __base_pointer __end_as_link() const _NOEXCEPT { return __node_pointer_traits::__unsafe_link_pointer_cast(const_cast<__node_base&>(__end_).__self()); } @@ -511,7 +499,7 @@ protected: _LIBCPP_HIDE_FROM_ABI size_type __node_alloc_max_size() const _NOEXCEPT { return __node_alloc_traits::max_size(__node_alloc()); } - _LIBCPP_HIDE_FROM_ABI static void __unlink_nodes(__link_pointer __f, __link_pointer __l) _NOEXCEPT; + _LIBCPP_HIDE_FROM_ABI static void __unlink_nodes(__base_pointer __f, __base_pointer __l) _NOEXCEPT; _LIBCPP_HIDE_FROM_ABI __list_imp() _NOEXCEPT_(is_nothrow_default_constructible<__node_allocator>::value); _LIBCPP_HIDE_FROM_ABI __list_imp(const allocator_type& __a); @@ -548,7 +536,7 @@ protected: } template - _LIBCPP_HIDE_FROM_ABI __node_pointer __create_node(__link_pointer __prev, __link_pointer __next, _Args&&... __args) { + _LIBCPP_HIDE_FROM_ABI __node_pointer __create_node(__base_pointer __prev, __base_pointer __next, _Args&&... __args) { __node_allocator& __alloc = __node_alloc(); __allocation_guard<__node_allocator> __guard(__alloc, 1); // Begin the lifetime of the node itself. Note that this doesn't begin the lifetime of the value @@ -593,7 +581,7 @@ private: // Unlink nodes [__f, __l] template -inline void __list_imp<_Tp, _Alloc>::__unlink_nodes(__link_pointer __f, __link_pointer __l) _NOEXCEPT { +inline void __list_imp<_Tp, _Alloc>::__unlink_nodes(__base_pointer __f, __base_pointer __l) _NOEXCEPT { __f->__prev_->__next_ = __l->__next_; __l->__next_->__prev_ = __f->__prev_; } @@ -621,8 +609,8 @@ __list_imp<_Tp, _Alloc>::~__list_imp() { template void __list_imp<_Tp, _Alloc>::clear() _NOEXCEPT { if (!empty()) { - __link_pointer __f = __end_.__next_; - __link_pointer __l = __end_as_link(); + __base_pointer __f = __end_.__next_; + __base_pointer __l = __end_as_link(); __unlink_nodes(__f, __l->__prev_); __sz() = 0; while (__f != __l) { @@ -668,7 +656,7 @@ class _LIBCPP_TEMPLATE_VIS list : private __list_imp<_Tp, _Alloc> { typedef typename base::__node_alloc_traits __node_alloc_traits; typedef typename base::__node_base __node_base; typedef typename base::__node_base_pointer __node_base_pointer; - typedef typename base::__link_pointer __link_pointer; + typedef typename base::__base_pointer __base_pointer; public: typedef _Tp value_type; @@ -917,9 +905,9 @@ private: template _LIBCPP_HIDE_FROM_ABI iterator __insert_with_sentinel(const_iterator __p, _Iterator __f, _Sentinel __l); - _LIBCPP_HIDE_FROM_ABI static void __link_nodes(__link_pointer __p, __link_pointer __f, __link_pointer __l); - _LIBCPP_HIDE_FROM_ABI void __link_nodes_at_front(__link_pointer __f, __link_pointer __l); - _LIBCPP_HIDE_FROM_ABI void __link_nodes_at_back(__link_pointer __f, __link_pointer __l); + _LIBCPP_HIDE_FROM_ABI static void __link_nodes(__base_pointer __p, __base_pointer __f, __base_pointer __l); + _LIBCPP_HIDE_FROM_ABI void __link_nodes_at_front(__base_pointer __f, __base_pointer __l); + _LIBCPP_HIDE_FROM_ABI void __link_nodes_at_back(__base_pointer __f, __base_pointer __l); _LIBCPP_HIDE_FROM_ABI iterator __iterator(size_type __n); // TODO: Make this _LIBCPP_HIDE_FROM_ABI template @@ -953,7 +941,7 @@ list(from_range_t, _Range&&, _Alloc = _Alloc()) -> list -inline void list<_Tp, _Alloc>::__link_nodes(__link_pointer __p, __link_pointer __f, __link_pointer __l) { +inline void list<_Tp, _Alloc>::__link_nodes(__base_pointer __p, __base_pointer __f, __base_pointer __l) { __p->__prev_->__next_ = __f; __f->__prev_ = __p->__prev_; __p->__prev_ = __l; @@ -962,7 +950,7 @@ inline void list<_Tp, _Alloc>::__link_nodes(__link_pointer __p, __link_pointer _ // Link in nodes [__f, __l] at the front of the list template -inline void list<_Tp, _Alloc>::__link_nodes_at_front(__link_pointer __f, __link_pointer __l) { +inline void list<_Tp, _Alloc>::__link_nodes_at_front(__base_pointer __f, __base_pointer __l) { __f->__prev_ = base::__end_as_link(); __l->__next_ = base::__end_.__next_; __l->__next_->__prev_ = __l; @@ -971,7 +959,7 @@ inline void list<_Tp, _Alloc>::__link_nodes_at_front(__link_pointer __f, __link_ // Link in nodes [__f, __l] at the back of the list template -inline void list<_Tp, _Alloc>::__link_nodes_at_back(__link_pointer __f, __link_pointer __l) { +inline void list<_Tp, _Alloc>::__link_nodes_at_back(__base_pointer __f, __base_pointer __l) { __l->__next_ = base::__end_as_link(); __f->__prev_ = base::__end_.__prev_; __f->__prev_->__next_ = __f; @@ -1163,7 +1151,7 @@ list<_Tp, _Alloc>::insert(const_iterator __p, size_type __n, const value_type& _ #ifndef _LIBCPP_HAS_NO_EXCEPTIONS } catch (...) { while (true) { - __link_pointer __prev = __e.__ptr_->__prev_; + __base_pointer __prev = __e.__ptr_->__prev_; __node_pointer __current = __e.__ptr_->__as_node(); this->__delete_node(__current); if (__prev == 0) @@ -1205,7 +1193,7 @@ list<_Tp, _Alloc>::__insert_with_sentinel(const_iterator __p, _Iterator __f, _Se #ifndef _LIBCPP_HAS_NO_EXCEPTIONS } catch (...) { while (true) { - __link_pointer __prev = __e.__ptr_->__prev_; + __base_pointer __prev = __e.__ptr_->__prev_; __node_pointer __current = __e.__ptr_->__as_node(); this->__delete_node(__current); if (__prev == 0) @@ -1224,7 +1212,7 @@ list<_Tp, _Alloc>::__insert_with_sentinel(const_iterator __p, _Iterator __f, _Se template void list<_Tp, _Alloc>::push_front(const value_type& __x) { __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, __x); - __link_pointer __nl = __node->__as_link(); + __base_pointer __nl = __node->__as_link(); __link_nodes_at_front(__nl, __nl); ++base::__sz(); } @@ -1232,7 +1220,7 @@ void list<_Tp, _Alloc>::push_front(const value_type& __x) { template void list<_Tp, _Alloc>::push_back(const value_type& __x) { __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, __x); - __link_pointer __nl = __node->__as_link(); + __base_pointer __nl = __node->__as_link(); __link_nodes_at_back(__nl, __nl); ++base::__sz(); } @@ -1242,7 +1230,7 @@ void list<_Tp, _Alloc>::push_back(const value_type& __x) { template void list<_Tp, _Alloc>::push_front(value_type&& __x) { __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::move(__x)); - __link_pointer __nl = __node->__as_link(); + __base_pointer __nl = __node->__as_link(); __link_nodes_at_front(__nl, __nl); ++base::__sz(); } @@ -1250,7 +1238,7 @@ void list<_Tp, _Alloc>::push_front(value_type&& __x) { template void list<_Tp, _Alloc>::push_back(value_type&& __x) { __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::move(__x)); - __link_pointer __nl = __node->__as_link(); + __base_pointer __nl = __node->__as_link(); __link_nodes_at_back(__nl, __nl); ++base::__sz(); } @@ -1265,7 +1253,7 @@ void list<_Tp, _Alloc>::emplace_front(_Args&&... __args) { __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::forward<_Args>(__args)...); - __link_pointer __nl = __node->__as_link(); + __base_pointer __nl = __node->__as_link(); __link_nodes_at_front(__nl, __nl); ++base::__sz(); # if _LIBCPP_STD_VER >= 17 @@ -1283,7 +1271,7 @@ void list<_Tp, _Alloc>::emplace_back(_Args&&... __args) { __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::forward<_Args>(__args)...); - __link_pointer __nl = __node->__as_link(); + __base_pointer __nl = __node->__as_link(); __link_nodes_at_back(__nl, __nl); ++base::__sz(); # if _LIBCPP_STD_VER >= 17 @@ -1296,7 +1284,7 @@ template typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::emplace(const_iterator __p, _Args&&... __args) { __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::forward<_Args>(__args)...); - __link_pointer __nl = __node->__as_link(); + __base_pointer __nl = __node->__as_link(); __link_nodes(__p.__ptr_, __nl, __nl); ++base::__sz(); return iterator(__nl); @@ -1305,7 +1293,7 @@ typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::emplace(const_iterator _ template typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::insert(const_iterator __p, value_type&& __x) { __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, std::move(__x)); - __link_pointer __nl = __node->__as_link(); + __base_pointer __nl = __node->__as_link(); __link_nodes(__p.__ptr_, __nl, __nl); ++base::__sz(); return iterator(__nl); @@ -1316,7 +1304,7 @@ typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::insert(const_iterator __ template void list<_Tp, _Alloc>::pop_front() { _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "list::pop_front() called with empty list"); - __link_pointer __n = base::__end_.__next_; + __base_pointer __n = base::__end_.__next_; base::__unlink_nodes(__n, __n); --base::__sz(); this->__delete_node(__n->__as_node()); @@ -1325,7 +1313,7 @@ void list<_Tp, _Alloc>::pop_front() { template void list<_Tp, _Alloc>::pop_back() { _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(!empty(), "list::pop_back() called on an empty list"); - __link_pointer __n = base::__end_.__prev_; + __base_pointer __n = base::__end_.__prev_; base::__unlink_nodes(__n, __n); --base::__sz(); this->__delete_node(__n->__as_node()); @@ -1334,8 +1322,8 @@ void list<_Tp, _Alloc>::pop_back() { template typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::erase(const_iterator __p) { _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__p != end(), "list::erase(iterator) called with a non-dereferenceable iterator"); - __link_pointer __n = __p.__ptr_; - __link_pointer __r = __n->__next_; + __base_pointer __n = __p.__ptr_; + __base_pointer __r = __n->__next_; base::__unlink_nodes(__n, __n); --base::__sz(); this->__delete_node(__n->__as_node()); @@ -1347,7 +1335,7 @@ typename list<_Tp, _Alloc>::iterator list<_Tp, _Alloc>::erase(const_iterator __f if (__f != __l) { base::__unlink_nodes(__f.__ptr_, __l.__ptr_->__prev_); while (__f != __l) { - __link_pointer __n = __f.__ptr_; + __base_pointer __n = __f.__ptr_; ++__f; --base::__sz(); this->__delete_node(__n->__as_node()); @@ -1376,7 +1364,7 @@ void list<_Tp, _Alloc>::resize(size_type __n) { #ifndef _LIBCPP_HAS_NO_EXCEPTIONS } catch (...) { while (true) { - __link_pointer __prev = __e.__ptr_->__prev_; + __base_pointer __prev = __e.__ptr_->__prev_; __node_pointer __current = __e.__ptr_->__as_node(); this->__delete_node(__current); if (__prev == 0) @@ -1400,7 +1388,7 @@ void list<_Tp, _Alloc>::resize(size_type __n, const value_type& __x) { size_type __ds = 0; __node_pointer __node = this->__create_node(/* prev = */ nullptr, /* next = */ nullptr, __x); ++__ds; - __link_pointer __nl = __node->__as_link(); + __base_pointer __nl = __node->__as_link(); iterator __r = iterator(__nl); iterator __e = __r; #ifndef _LIBCPP_HAS_NO_EXCEPTIONS @@ -1412,7 +1400,7 @@ void list<_Tp, _Alloc>::resize(size_type __n, const value_type& __x) { #ifndef _LIBCPP_HAS_NO_EXCEPTIONS } catch (...) { while (true) { - __link_pointer __prev = __e.__ptr_->__prev_; + __base_pointer __prev = __e.__ptr_->__prev_; __node_pointer __current = __e.__ptr_->__as_node(); this->__delete_node(__current); if (__prev == 0) @@ -1432,8 +1420,8 @@ void list<_Tp, _Alloc>::splice(const_iterator __p, list& __c) { _LIBCPP_ASSERT_VALID_INPUT_RANGE( this != std::addressof(__c), "list::splice(iterator, list) called with this == &list"); if (!__c.empty()) { - __link_pointer __f = __c.__end_.__next_; - __link_pointer __l = __c.__end_.__prev_; + __base_pointer __f = __c.__end_.__next_; + __base_pointer __l = __c.__end_.__prev_; base::__unlink_nodes(__f, __l); __link_nodes(__p.__ptr_, __f, __l); base::__sz() += __c.__sz(); @@ -1444,7 +1432,7 @@ void list<_Tp, _Alloc>::splice(const_iterator __p, list& __c) { template void list<_Tp, _Alloc>::splice(const_iterator __p, list& __c, const_iterator __i) { if (__p.__ptr_ != __i.__ptr_ && __p.__ptr_ != __i.__ptr_->__next_) { - __link_pointer __f = __i.__ptr_; + __base_pointer __f = __i.__ptr_; base::__unlink_nodes(__f, __f); __link_nodes(__p.__ptr_, __f, __f); --__c.__sz(); @@ -1455,9 +1443,9 @@ void list<_Tp, _Alloc>::splice(const_iterator __p, list& __c, const_iterator __i template void list<_Tp, _Alloc>::splice(const_iterator __p, list& __c, const_iterator __f, const_iterator __l) { if (__f != __l) { - __link_pointer __first = __f.__ptr_; + __base_pointer __first = __f.__ptr_; --__l; - __link_pointer __last = __l.__ptr_; + __base_pointer __last = __l.__ptr_; if (this != std::addressof(__c)) { size_type __s = std::distance(__f, __l) + 1; __c.__sz() -= __s; @@ -1545,8 +1533,8 @@ void list<_Tp, _Alloc>::merge(list& __c, _Comp __comp) { ; base::__sz() += __ds; __c.__sz() -= __ds; - __link_pointer __f = __f2.__ptr_; - __link_pointer __l = __m2.__ptr_->__prev_; + __base_pointer __f = __f2.__ptr_; + __base_pointer __l = __m2.__ptr_->__prev_; __f2 = __m2; base::__unlink_nodes(__f, __l); __m2 = std::next(__f1); @@ -1580,7 +1568,7 @@ list<_Tp, _Alloc>::__sort(iterator __f1, iterator __e2, size_type __n, _Comp& __ return __f1; case 2: if (__comp(*--__e2, *__f1)) { - __link_pointer __f = __e2.__ptr_; + __base_pointer __f = __e2.__ptr_; base::__unlink_nodes(__f, __f); __link_nodes(__f1.__ptr_, __f, __f); return __e2; @@ -1595,8 +1583,8 @@ list<_Tp, _Alloc>::__sort(iterator __f1, iterator __e2, size_type __n, _Comp& __ iterator __m2 = std::next(__f2); for (; __m2 != __e2 && __comp(*__m2, *__f1); ++__m2) ; - __link_pointer __f = __f2.__ptr_; - __link_pointer __l = __m2.__ptr_->__prev_; + __base_pointer __f = __f2.__ptr_; + __base_pointer __l = __m2.__ptr_->__prev_; __r = __f2; __e1 = __f2 = __m2; base::__unlink_nodes(__f, __l); @@ -1610,8 +1598,8 @@ list<_Tp, _Alloc>::__sort(iterator __f1, iterator __e2, size_type __n, _Comp& __ iterator __m2 = std::next(__f2); for (; __m2 != __e2 && __comp(*__m2, *__f1); ++__m2) ; - __link_pointer __f = __f2.__ptr_; - __link_pointer __l = __m2.__ptr_->__prev_; + __base_pointer __f = __f2.__ptr_; + __base_pointer __l = __m2.__ptr_->__prev_; if (__e1 == __f2) __e1 = __m2; __f2 = __m2;