diff --git a/src/main.cpp b/src/main.cpp
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -19,18 +19,52 @@
 
 #include <QApplication>
 #include <QtGlobal>
+#include <iostream>
 
 #include "mainwindow.h"
 #include "tooltipfilter.h"
 #include "version.h"
 
-MainWindow* pMainWindow;
+MainWindow* pMainWindow = nullptr;
 
 void messageHandler(QtMsgType type, const QMessageLogContext &context,
                     const QString &msg)
 {
-    // TODO: don't call MainWindow::messageHandler if window is destroyed
-    pMainWindow->messageHandler(type, context, msg);
+    QString logString;
+
+    switch (type)
+    {
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 5, 0))
+        case QtInfoMsg:
+            logString = "[Info] " + msg;
+            break;
+#endif
+        case QtDebugMsg:
+            logString = "[Debug] " + msg;
+            break;
+        case QtWarningMsg:
+            logString = "[Warning] " + msg;
+            break;
+        case QtCriticalMsg:
+            logString = "[Error] " + msg;
+            break;
+        case QtFatalMsg:
+            logString = "[Fatal] " + msg;
+            break;
+    }
+
+    std::cerr << logString.toStdString() << std::endl;
+
+    if (pMainWindow != nullptr)
+    {
+        // TODO: don't call MainWindow::messageHandler if window is destroyed
+        pMainWindow->messageHandler(type, logString, msg);
+    }
+
+    if (type == QtFatalMsg)
+    {
+        __builtin_trap();
+    }
 }
 
 int main(int argc, char *argv[])
@@ -38,11 +72,11 @@ int main(int argc, char *argv[])
     QApplication a(argc, argv);
     QApplication::setApplicationName(PROGRAM_NAME_STRING);
     QApplication::setApplicationVersion(VERSION_STRING);
+
+    qInstallMessageHandler(messageHandler);
     MainWindow w;
     pMainWindow = &w;
 
-    qInstallMessageHandler(messageHandler);
-
     ToolTipFilter ttf;
     a.installEventFilter(&ttf);
 
diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -478,44 +478,16 @@ PlotViewSettings MainWindow::viewSetting
 }
 
 void MainWindow::messageHandler(QtMsgType type,
-                                const QMessageLogContext &context,
+                                const QString &logString,
                                 const QString &msg)
 {
-    QString logString;
-
-    switch (type)
-    {
-#if (QT_VERSION >= QT_VERSION_CHECK(5, 5, 0))
-        case QtInfoMsg:
-            logString = "[Info] " + msg;
-            break;
-#endif
-        case QtDebugMsg:
-            logString = "[Debug] " + msg;
-            break;
-        case QtWarningMsg:
-            logString = "[Warning] " + msg;
-            break;
-        case QtCriticalMsg:
-            logString = "[Error] " + msg;
-            break;
-        case QtFatalMsg:
-            logString = "[Fatal] " + msg;
-            break;
-    }
-
-    if (ui != NULL) ui->ptLog->appendPlainText(logString);
-    std::cerr << logString.toStdString() << std::endl;
+    if (ui != NULL)
+        ui->ptLog->appendPlainText(logString);
 
     if (type != QtDebugMsg && ui != NULL)
     {
         ui->statusBar->showMessage(msg, 5000);
     }
-
-    if (type == QtFatalMsg)
-    {
-        __builtin_trap();
-    }
 }
 
 void MainWindow::saveAllSettings(QSettings* settings)
diff --git a/src/mainwindow.h b/src/mainwindow.h
--- a/src/mainwindow.h
+++ b/src/mainwindow.h
@@ -62,8 +62,7 @@ public:
 
     PlotViewSettings viewSettings() const;
 
-    void messageHandler(QtMsgType type, const QMessageLogContext &context,
-                        const QString &msg);
+    void messageHandler(QtMsgType type, const QString &logString, const QString &msg);
 
 private:
     Ui::MainWindow *ui;