Fix leak in __enable_weak_this(). Thanks to Arthur O'Dwyer for finding it.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@271487 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 2 deletions

diff --git a/include/memory b/include/memory
index 014635234..8324d1c5f 100644
--- a/include/memory
+++ b/include/memory
@@ -4122,9 +4122,11 @@ private:
         {
             if (__e && __e->__weak_this_.expired())
             {
-                __e->__weak_this_.__ptr_ = const_cast<_Yp*>(static_cast<const _Yp*>(__e));
-                __e->__weak_this_.__cntrl_ = __cntrl_;
+                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);
             }
         }