Fix PR27115 - enable_shared_from_this does not work as a virtual base class. See https://llvm.org/bugs/show_bug.cgi?id=27115 The problem was that the conversion from 'const enable_shared_from_this<T>*' to 'const T*' didn't work if T inherited enable_shared_from_this as a virtual base class. The fix is to take the original pointer passed to shared_ptr's constructor in the __enable_weak_this method and perform an upcast to 'const T*' instead of performing a downcast from the enable_shared_from_this base. git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@273835 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/memory b/include/memory index 587d305..47963e0 100644 --- a/include/memory +++ b/include/memory
@@ -4115,23 +4115,22 @@ private: - template <class _Yp> + template <class _Yp, class _OrigPtr> _LIBCPP_INLINE_VISIBILITY void - __enable_weak_this(const enable_shared_from_this<_Yp>* __e) _NOEXCEPT + __enable_weak_this(const enable_shared_from_this<_Yp>* __e, + _OrigPtr* __ptr) _NOEXCEPT { + typedef typename remove_cv<_Yp>::type _RawYp; if (__e && __e->__weak_this_.expired()) { - weak_ptr<_Yp> __tmp; - __tmp.__ptr_ = const_cast<_Yp*>(static_cast<const _Yp*>(__e)); - __tmp.__cntrl_ = __cntrl_; - __cntrl_->__add_weak(); - __e->__weak_this_.swap(__tmp); + __e->__weak_this_ = shared_ptr<_RawYp>(*this, + const_cast<_RawYp*>(static_cast<const _Yp*>(__ptr))); } } _LIBCPP_INLINE_VISIBILITY - void __enable_weak_this(const volatile void*) _NOEXCEPT {} + void __enable_weak_this(const volatile void*, const volatile void*) _NOEXCEPT {} template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY shared_ptr; template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY weak_ptr; @@ -4165,7 +4164,7 @@ typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk; __cntrl_ = new _CntrlBlk(__p, default_delete<_Yp>(), allocator<_Yp>()); __hold.release(); - __enable_weak_this(__p); + __enable_weak_this(__p, __p); } template<class _Tp> @@ -4180,7 +4179,7 @@ #endif // _LIBCPP_NO_EXCEPTIONS typedef __shared_ptr_pointer<_Yp*, _Dp, allocator<_Yp> > _CntrlBlk; __cntrl_ = new _CntrlBlk(__p, __d, allocator<_Yp>()); - __enable_weak_this(__p); + __enable_weak_this(__p, __p); #ifndef _LIBCPP_NO_EXCEPTIONS } catch (...) @@ -4230,7 +4229,7 @@ ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get()))) _CntrlBlk(__p, __d, __a); __cntrl_ = _VSTD::addressof(*__hold2.release()); - __enable_weak_this(__p); + __enable_weak_this(__p, __p); #ifndef _LIBCPP_NO_EXCEPTIONS } catch (...) @@ -4341,7 +4340,7 @@ { typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk; __cntrl_ = new _CntrlBlk(__r.get(), default_delete<_Yp>(), allocator<_Yp>()); - __enable_weak_this(__r.get()); + __enable_weak_this(__r.get(), __r.get()); __r.release(); } @@ -4369,7 +4368,7 @@ { typedef __shared_ptr_pointer<_Yp*, _Dp, allocator<_Yp> > _CntrlBlk; __cntrl_ = new _CntrlBlk(__r.get(), __r.get_deleter(), allocator<_Yp>()); - __enable_weak_this(__r.get()); + __enable_weak_this(__r.get(), __r.get()); } __r.release(); } @@ -4400,7 +4399,7 @@ reference_wrapper<typename remove_reference<_Dp>::type>, allocator<_Yp> > _CntrlBlk; __cntrl_ = new _CntrlBlk(__r.get(), ref(__r.get_deleter()), allocator<_Yp>()); - __enable_weak_this(__r.get()); + __enable_weak_this(__r.get(), __r.get()); } __r.release(); } @@ -4421,7 +4420,7 @@ shared_ptr<_Tp> __r; __r.__ptr_ = __hold2.get()->get(); __r.__cntrl_ = __hold2.release(); - __r.__enable_weak_this(__r.__ptr_); + __r.__enable_weak_this(__r.__ptr_, __r.__ptr_); return __r; } @@ -4440,7 +4439,7 @@ shared_ptr<_Tp> __r; __r.__ptr_ = __hold2.get()->get(); __r.__cntrl_ = _VSTD::addressof(*__hold2.release()); - __r.__enable_weak_this(__r.__ptr_); + __r.__enable_weak_this(__r.__ptr_, __r.__ptr_); return __r; } @@ -4459,7 +4458,7 @@ shared_ptr<_Tp> __r; __r.__ptr_ = __hold2.get()->get(); __r.__cntrl_ = __hold2.release(); - __r.__enable_weak_this(__r.__ptr_); + __r.__enable_weak_this(__r.__ptr_, __r.__ptr_); return __r; } @@ -4477,7 +4476,7 @@ shared_ptr<_Tp> __r; __r.__ptr_ = __hold2.get()->get(); __r.__cntrl_ = __hold2.release(); - __r.__enable_weak_this(__r.__ptr_); + __r.__enable_weak_this(__r.__ptr_, __r.__ptr_); return __r; } @@ -4495,7 +4494,7 @@ shared_ptr<_Tp> __r; __r.__ptr_ = __hold2.get()->get(); __r.__cntrl_ = __hold2.release(); - __r.__enable_weak_this(__r.__ptr_); + __r.__enable_weak_this(__r.__ptr_, __r.__ptr_); return __r; } @@ -4513,7 +4512,7 @@ shared_ptr<_Tp> __r; __r.__ptr_ = __hold2.get()->get(); __r.__cntrl_ = __hold2.release(); - __r.__enable_weak_this(__r.__ptr_); + __r.__enable_weak_this(__r.__ptr_, __r.__ptr_); return __r; } @@ -4532,7 +4531,7 @@ shared_ptr<_Tp> __r; __r.__ptr_ = __hold2.get()->get(); __r.__cntrl_ = _VSTD::addressof(*__hold2.release()); - __r.__enable_weak_this(__r.__ptr_); + __r.__enable_weak_this(__r.__ptr_, __r.__ptr_); return __r; } @@ -4551,7 +4550,7 @@ shared_ptr<_Tp> __r; __r.__ptr_ = __hold2.get()->get(); __r.__cntrl_ = _VSTD::addressof(*__hold2.release()); - __r.__enable_weak_this(__r.__ptr_); + __r.__enable_weak_this(__r.__ptr_, __r.__ptr_); return __r; } @@ -4570,7 +4569,7 @@ shared_ptr<_Tp> __r; __r.__ptr_ = __hold2.get()->get(); __r.__cntrl_ = _VSTD::addressof(*__hold2.release()); - __r.__enable_weak_this(__r.__ptr_); + __r.__enable_weak_this(__r.__ptr_, __r.__ptr_); return __r; } @@ -4589,7 +4588,7 @@ shared_ptr<_Tp> __r; __r.__ptr_ = __hold2.get()->get(); __r.__cntrl_ = _VSTD::addressof(*__hold2.release()); - __r.__enable_weak_this(__r.__ptr_); + __r.__enable_weak_this(__r.__ptr_, __r.__ptr_); return __r; } 