diff --git a/qucs-transcalc/helpdialog.cpp b/qucs-transcalc/helpdialog.cpp
index 33d06344..155a2e5f 100644
--- a/qucs-transcalc/helpdialog.cpp
+++ b/qucs-transcalc/helpdialog.cpp
@@ -46,7 +46,7 @@ HelpDialog::HelpDialog(QWidget *parent)
   resize(350, 230);
 
   vLayout = new QVBoxLayout(this);
-  vLayout->setMargin(3);
+  vLayout->setContentsMargins(3,3,3,3);
   vLayout->setSpacing(3);
 
   Text = new QTextEdit(s, this);
diff --git a/qucs-transcalc/main.cpp b/qucs-transcalc/main.cpp
index 2a1cc69e..e9b32670 100644
--- a/qucs-transcalc/main.cpp
+++ b/qucs-transcalc/main.cpp
@@ -23,7 +23,6 @@
 
 #include <QApplication>
 #include <QString>
-#include <QTextCodec>
 #include <QTranslator>
 #include <QFile>
 #include <QTextStream>
diff --git a/qucs-transcalc/optionsdialog.cpp b/qucs-transcalc/optionsdialog.cpp
index 8968b86c..8d8d23f1 100644
--- a/qucs-transcalc/optionsdialog.cpp
+++ b/qucs-transcalc/optionsdialog.cpp
@@ -37,7 +37,7 @@ OptionsDialog::OptionsDialog(QWidget *parent)
 
   // --------  create dialog widgets  ------------
   vLayout = new QVBoxLayout(this);
-  vLayout->setMargin(3);
+  vLayout->setContentsMargins(3,3,3,3);
   vLayout->setSpacing(3);
 
   QGroupBox * unitsGroup = new QGroupBox(tr("Units"));
diff --git a/qucs-transcalc/qucstrans.cpp b/qucs-transcalc/qucstrans.cpp
index a5ec61db..aedd6dcb 100644
--- a/qucs-transcalc/qucstrans.cpp
+++ b/qucs-transcalc/qucstrans.cpp
@@ -43,7 +43,7 @@
 #include <QDir>
 #include <QButtonGroup>
 #include <QStackedWidget>
-#include <QRegExp>
+#include <QRegularExpression>
 #include <QValidator>
 #include <QClipboard>
 #include <QApplication>