PR libstdc++/53830

[pf3gnuchains/gcc-fork.git] / libstdc++-v3 / include / std / condition_variable

diff --git a/libstdc++-v3/include/std/condition_variable b/libstdc++-v3/include/std/condition_variable
index c4e2080..85b50a7 100644 (file)
--- a/libstdc++-v3/include/std/condition_variable
+++ b/libstdc++-v3/include/std/condition_variable
@@ -176,6 +176,26 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     condition_variable                 _M_cond;
     mutex                              _M_mutex;
 
+    // scoped unlock - unlocks in ctor, re-locks in dtor
+    template<typename _Lock>
+      struct _Unlock
+      {
+       explicit _Unlock(_Lock& __lk) : _M_lock(__lk) { __lk.unlock(); }
+
+       ~_Unlock() noexcept(false)
+       {
+         if (uncaught_exception())
+           __try { _M_lock.lock(); } __catch(...) { }
+         else
+           _M_lock.lock();
+       }
+
+       _Unlock(const _Unlock&) = delete;
+       _Unlock& operator=(const _Unlock&) = delete;
+
+       _Lock& _M_lock;
+      };
+
   public:
 
     condition_variable_any() noexcept;
@@ -202,21 +222,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       void
       wait(_Lock& __lock)
       {
-       // scoped unlock - unlocks in ctor, re-locks in dtor
-       struct _Unlock {
-         explicit _Unlock(_Lock& __lk) : _M_lock(__lk) { __lk.unlock(); }
-         ~_Unlock() noexcept(false)
-         {
-           if (uncaught_exception())
-             __try { _M_lock.lock(); } __catch(...) { }
-           else
-             _M_lock.lock();
-         }
-         _Lock& _M_lock;
-       };
-
        unique_lock<mutex> __my_lock(_M_mutex);
-       _Unlock __unlock(__lock);
+       _Unlock<_Lock> __unlock(__lock);
        // _M_mutex must be unlocked before re-locking __lock so move
        // ownership of _M_mutex lock to an object with shorter lifetime.
        unique_lock<mutex> __my_lock2(std::move(__my_lock));
@@ -237,11 +244,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       wait_until(_Lock& __lock,
                 const chrono::time_point<_Clock, _Duration>& __atime)
       {
-        unique_lock<mutex> __my_lock(_M_mutex);
-        __lock.unlock();
-        cv_status __status = _M_cond.wait_until(__my_lock, __atime);
-        __lock.lock();
-        return __status;
+       unique_lock<mutex> __my_lock(_M_mutex);
+       _Unlock<_Lock> __unlock(__lock);
+       // _M_mutex must be unlocked before re-locking __lock so move
+       // ownership of _M_mutex lock to an object with shorter lifetime.
+       unique_lock<mutex> __my_lock2(std::move(__my_lock));
+       return _M_cond.wait_until(__my_lock2, __atime);
       }
 
     template<typename _Lock, typename _Clock,