diff --git a/example/bench.cpp b/example/bench.cpp
index 94ca7dc3..abbd379a 100644
--- a/example/bench.cpp
+++ b/example/bench.cpp
@@ -15,7 +15,7 @@ using namespace c11log;
 using namespace utils;
 
 
-int main(int argc, char* argv[])
+int main_(int argc, char* argv[])
 {
     const unsigned int howmany = argc <= 1 ? 500000 : atoi(argv[1]);
 
diff --git a/include/c11log/details/fast_oss.h b/include/c11log/details/fast_oss.h
index 448a82ad..cb4c8f99 100644
--- a/include/c11log/details/fast_oss.h
+++ b/include/c11log/details/fast_oss.h
@@ -22,7 +22,6 @@ public:
 
     stack_devicebuf() = default;
     ~stack_devicebuf() = default;
-    stack_devicebuf& operator=(const stack_devicebuf&) = delete;
 
     stack_devicebuf(const stack_devicebuf& other) :std::basic_streambuf<char>(), _stackbuf(other._stackbuf)
     {}
@@ -34,6 +33,12 @@ public:
         other.clear();
     }
 
+    stack_devicebuf& operator=(stack_devicebuf&& other)
+    {
+        std::swap(_stackbuf, other._stackbuf);
+        return *this;
+    }
+
     const stackbuf_t& buf() const
     {
         return _stackbuf;
@@ -76,8 +81,7 @@ public:
     fast_oss() :std::ostream(&_dev) {}
     ~fast_oss() = default;
 
-    fast_oss& operator=(const fast_oss& other) = delete;
-    fast_oss& operator=(const fast_oss&& other) = delete;
+
 
     fast_oss(const fast_oss& other) :std::basic_ios<char>(), std::ostream(&_dev), _dev(other._dev)
     {}
@@ -87,6 +91,21 @@ public:
         other.clear();
     }
 
+
+    fast_oss& operator=(fast_oss&& other)
+    {
+        swap(*this, other);
+        return *this;
+    }
+
+    void swap(fast_oss& first, fast_oss& second) // nothrow
+    {
+        using std::swap;
+        swap(first._dev, second._dev);
+    }
+
+
+
     std::string str()
     {
         auto buffer = _dev.buf();
@@ -136,8 +155,8 @@ public:
         auto buffer = oss.buf();
         _dev.sputn(buffer.data(), buffer.size());
     }
-    
-    
+
+
 private:
     stack_devicebuf _dev;
 };
diff --git a/include/c11log/details/log_msg.h b/include/c11log/details/log_msg.h
index bb0d47b5..6faa4a5e 100644
--- a/include/c11log/details/log_msg.h
+++ b/include/c11log/details/log_msg.h
@@ -38,8 +38,8 @@ struct log_msg
         swap(l.level, r.level);
         swap(l.time, r.time);
         swap(l.tm_time, r.tm_time);
-        //swap(l.raw, r.raw);
-        //swap(l.formatted, r.formatted);
+        swap(l.raw, r.raw);
+        swap(l.formatted, r.formatted);
     }
 
 
diff --git a/include/c11log/details/stack_buf.h b/include/c11log/details/stack_buf.h
index d0f01dc5..6ea661ef 100644
--- a/include/c11log/details/stack_buf.h
+++ b/include/c11log/details/stack_buf.h
@@ -19,9 +19,6 @@ public:
     static const unsigned short stack_size = STACK_SIZE;
     stack_buf() :_v(), _stack_size(0) {}
     ~stack_buf() = default;
-
-    stack_buf& operator=(const stack_buf& other) = delete;
-
     stack_buf(const stack_buf& other):stack_buf(other, delegate_copy_move {})
     {}
 
@@ -29,6 +26,16 @@ public:
     {
         other.clear();
     }
+    template<class T1>
+    stack_buf& operator=(T1&& other)
+    {
+        _stack_size = other._stack_size;
+        if (other.vector_used())
+            _v = std::forward<T1>(other)._v;
+        else
+            std::copy_n(other._stack_array.begin(), other._stack_size, _stack_array.begin());
+        return *this;
+    }
 
     void append(const char* buf, std::size_t buf_size)
     {
@@ -62,14 +69,6 @@ public:
         _v.clear();
     }
 
-    /* bufpair_t get() const
-     {
-         if (vector_used())
-             return bufpair_t(_v.data(), _v.size());
-         else
-             return bufpair_t(_stack_array.data(), _stack_size);
-     }*/
-
     const char* data() const
     {
         if (vector_used())
diff --git a/include/c11log/logger.h b/include/c11log/logger.h
index 194f670b..f395cb90 100644
--- a/include/c11log/logger.h
+++ b/include/c11log/logger.h
@@ -114,8 +114,10 @@ inline c11log::logger::logger(const std::string& logger_name, const It& begin, c
 
 template <typename... Args>
 inline c11log::details::line_logger c11log::logger::log(level::level_enum lvl, const Args&... args) {
-    details::line_logger l(this, lvl, should_log(lvl));
-    _variadic_log(l, args...);
+    bool msg_enabled = should_log(lvl);
+    details::line_logger l(this, lvl, msg_enabled);
+    if (msg_enabled)
+        _variadic_log(l, args...);
     return l;
 }