diff --git a/include/log4cplus/qt6messagehandler.h b/include/log4cplus/qt6messagehandler.h
index cf21ba513..183ecc503 100644
--- a/include/log4cplus/qt6messagehandler.h
+++ b/include/log4cplus/qt6messagehandler.h
@@ -43,6 +43,7 @@
 #endif
 
 #include <QtCore>
+#include <type_traits>
 
 #if defined (_WIN32)
   #if defined (log4cplusqt6debugappender_EXPORTS) \
diff --git a/qt6debugappender/qt6debugappender.cxx b/qt6debugappender/qt6debugappender.cxx
index 41c976a50..6b99fc326 100644
--- a/qt6debugappender/qt6debugappender.cxx
+++ b/qt6debugappender/qt6debugappender.cxx
@@ -35,6 +35,7 @@
 #include <log4cplus/spi/factory.h>
 #include <log4cplus/spi/loggingevent.h>
 #include <log4cplus/logger.h>
+#include <cstdlib>
 #include <sstream>
 #include <iomanip>
 #include <QtGlobal>