Don't neglect to "return *this".

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@165860 91177308-0d34-0410-b5e6-96231b3b80d8

include/chrono

@@ -728,8 +728,8 @@ public:
 
     // arithmetic
 
-    _LIBCPP_INLINE_VISIBILITY time_point& operator+=(const duration& __d) {__d_ += __d;}
+	_LIBCPP_INLINE_VISIBILITY time_point& operator+=(const duration& __d) {__d_ += __d; return *this;}
-    _LIBCPP_INLINE_VISIBILITY time_point& operator-=(const duration& __d) {__d_ -= __d;}
+	_LIBCPP_INLINE_VISIBILITY time_point& operator-=(const duration& __d) {__d_ -= __d; return *this;}
 
     // special values
 

include/fstream

@@ -344,6 +344,7 @@ basic_filebuf<_CharT, _Traits>::operator=(basic_filebuf&& __rhs)
 {
     close();
     swap(__rhs);
+    return *this;
 }
 
 #endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES

include/functional

@@ -1351,6 +1351,7 @@ function<_Rp(_ArgTypes...)>::operator=(function&& __f) _NOEXCEPT
         __f_ = __f.__f_;
         __f.__f_ = 0;
     }
+    return *this;
 }
 
 template<class _Rp, class ..._ArgTypes>
@@ -1362,6 +1363,7 @@ function<_Rp(_ArgTypes...)>::operator=(nullptr_t) _NOEXCEPT
     else if (__f_)
         __f_->destroy_deallocate();
     __f_ = 0;
+    return *this;
 }
 
 template<class _Rp, class ..._ArgTypes>

include/future

@@ -1872,6 +1872,7 @@ __packaged_task_function<_Rp(_ArgTypes...)>::operator=(__packaged_task_function&
         __f_ = __f.__f_;
         __f.__f_ = nullptr;
     }
+    return *this;
 }
 
 template<class _Rp, class ..._ArgTypes>

include/regex

@@ -2562,6 +2562,7 @@ public:
         {
             __member_init(__f);
             __parse(__first, __last);
+            return *this;
         }
 
 #ifndef _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS

include/string

@@ -2208,6 +2208,7 @@ basic_string<_CharT, _Traits, _Allocator>::assign(_InputIterator __first, _Input
     clear();
     for (; __first != __last; ++__first)
         push_back(*__first);
+    return *this;
 }
 
 template <class _CharT, class _Traits, class _Allocator>

include/vector

@@ -2700,6 +2700,7 @@ vector<bool, _Allocator>::operator=(vector&& __v)
 {
     __move_assign(__v, integral_constant<bool,
           __storage_traits::propagate_on_container_move_assignment::value>());
+    return *this;
 }
 
 template <class _Allocator>