Changed locking code to std::atomic
diff --git a/src/main/cpp/writerappender.cpp b/src/main/cpp/writerappender.cpp
index 235717c..4e85a44 100644
--- a/src/main/cpp/writerappender.cpp
+++ b/src/main/cpp/writerappender.cpp
@@ -305,6 +305,5 @@
 
 void WriterAppender::setImmediateFlush(bool value)
 {
-    std::unique_lock lock(mutex);
     immediateFlush = value;
 }
diff --git a/src/main/include/log4cxx/writerappender.h b/src/main/include/log4cxx/writerappender.h
index d8c6980..9907ddf 100644
--- a/src/main/include/log4cxx/writerappender.h
+++ b/src/main/include/log4cxx/writerappender.h
@@ -53,7 +53,7 @@
     <code>true</code> by default.
 
     */
-    bool immediateFlush;
+	std::atomic<bool> immediateFlush;
 
     /**
     The encoding to use when opening an input stream.