diff --git a/src/app/qgsmaptooladdfeature.h b/src/app/qgsmaptooladdfeature.h
index 77f4ea49be2f..c081b62f08aa 100644
--- a/src/app/qgsmaptooladdfeature.h
+++ b/src/app/qgsmaptooladdfeature.h
@@ -13,6 +13,9 @@
  *                                                                         *
  ***************************************************************************/
 
+#ifndef QGSMAPTOOLADDFEATURE_H
+#define QGSMAPTOOLADDFEATURE_H
+
 #include "qgsmaptooldigitizefeature.h"
 #include "qgis_app.h"
 
@@ -51,3 +54,5 @@ class APP_EXPORT QgsMapToolAddFeature : public QgsMapToolDigitizeFeature
     */
     bool mCheckGeometryType;
 };
+
+#endif // QGSMAPTOOLADDFEATURE_H
diff --git a/src/app/qgsmaptooladdpart.h b/src/app/qgsmaptooladdpart.h
index 6037f8b1f901..9ab97db60473 100644
--- a/src/app/qgsmaptooladdpart.h
+++ b/src/app/qgsmaptooladdpart.h
@@ -13,6 +13,9 @@
  *                                                                         *
  ***************************************************************************/
 
+#ifndef QGSMAPTOOLADDPART_H
+#define QGSMAPTOOLADDPART_H
+
 #include "qgsmaptoolcapturelayergeometry.h"
 #include "qgis_app.h"
 
@@ -47,3 +50,5 @@ class APP_EXPORT QgsMapToolAddPart : public QgsMapToolCaptureLayerGeometry
 
     void finalizeEditCommand( QgsVectorLayer *layer, Qgis::GeometryOperationResult errorCode );
 };
+
+#endif // QGSMAPTOOLADDPART_H
diff --git a/src/app/qgsmaptooladdring.h b/src/app/qgsmaptooladdring.h
index de7c04bcfe84..d9893ba6b5ef 100644
--- a/src/app/qgsmaptooladdring.h
+++ b/src/app/qgsmaptooladdring.h
@@ -13,6 +13,9 @@
  *                                                                         *
  ***************************************************************************/
 
+#ifndef QGSMAPTOOLADDRING_H
+#define QGSMAPTOOLADDRING_H
+
 #include "qgsmaptoolcapture.h"
 #include "qgis_app.h"
 
@@ -31,3 +34,5 @@ class APP_EXPORT QgsMapToolAddRing: public QgsMapToolCapture
     QgsVectorLayer *getCheckLayer();
     void polygonCaptured( const QgsCurvePolygon *polygon ) override;
 };
+
+#endif // QGSMAPTOOLADDRING_H
diff --git a/src/app/qgsmaptoolfillring.h b/src/app/qgsmaptoolfillring.h
index 8d551638b241..05e7acd0e9f8 100644
--- a/src/app/qgsmaptoolfillring.h
+++ b/src/app/qgsmaptoolfillring.h
@@ -14,6 +14,9 @@
  *                                                                         *
  ***************************************************************************/
 
+#ifndef QGSMAPTOOLFILLRING_H
+#define QGSMAPTOOLFILLRING_H
+
 #include "qgsmaptoolcapture.h"
 #include "qgis_app.h"
 
@@ -40,3 +43,5 @@ class APP_EXPORT QgsMapToolFillRing: public QgsMapToolCapture
 
     QgsVectorLayer *getCheckLayer();
 };
+
+#endif // QGSMAPTOOLFILLRING_H
diff --git a/src/app/qgsprojectproperties.h b/src/app/qgsprojectproperties.h
index d0ba5799a4f7..ba136e0593cc 100644
--- a/src/app/qgsprojectproperties.h
+++ b/src/app/qgsprojectproperties.h
@@ -17,6 +17,9 @@
  ***************************************************************************/
 
 
+#ifndef QGSPROJECTPROPERTIES_H
+#define QGSPROJECTPROPERTIES_H
+
 #include "ui_qgsprojectpropertiesbase.h"
 
 #include "qgsoptionsdialogbase.h"
@@ -305,3 +308,5 @@ class APP_EXPORT QgsProjectProperties : public QgsOptionsDialogBase, private Ui:
 
     friend class TestQgsProjectProperties;
 };
+
+#endif // QGSPROJECTPROPERTIES_H
diff --git a/src/core/providers/memory/qgsmemoryprovider.h b/src/core/providers/memory/qgsmemoryprovider.h
index 5101f2167841..b423538382c8 100644
--- a/src/core/providers/memory/qgsmemoryprovider.h
+++ b/src/core/providers/memory/qgsmemoryprovider.h
@@ -13,6 +13,9 @@
  *                                                                         *
  ***************************************************************************/
 
+#ifndef QGSMEMORYPROVIDER_H
+#define QGSMEMORYPROVIDER_H
+
 #define SIP_NO_FILE
 
 #include "qgsvectordataprovider.h"
@@ -113,3 +116,4 @@ class QgsMemoryProviderMetadata final: public QgsProviderMetadata
 };
 
 ///@endcond
+#endif // QGSMEMORYPROVIDER_H
diff --git a/src/gui/qgsdial.h b/src/gui/qgsdial.h
index 68583e8bf1dc..bb616117e848 100644
--- a/src/gui/qgsdial.h
+++ b/src/gui/qgsdial.h
@@ -15,6 +15,9 @@
  *                                                                         *
  ***************************************************************************/
 
+#ifndef QGSDIAL_H
+#define QGSDIAL_H
+
 #include <QDial>
 #include <QVariant>
 #include "qgis_gui.h"
@@ -57,3 +60,5 @@ class GUI_EXPORT QgsDial : public QDial
 
     QVariant mMin, mMax, mStep, mValue;
 };
+
+#endif // QGSDIAL_H
diff --git a/src/gui/qgsslider.h b/src/gui/qgsslider.h
index b0c92b0a6265..752aebb9b518 100644
--- a/src/gui/qgsslider.h
+++ b/src/gui/qgsslider.h
@@ -15,6 +15,9 @@
  *                                                                         *
  ***************************************************************************/
 
+#ifndef QGSSLIDER_H
+#define QGSSLIDER_H
+
 #include <QSlider>
 #include "qgis_sip.h"
 #include <QVariant>
@@ -57,3 +60,5 @@ class GUI_EXPORT QgsSlider : public QSlider
 
     QVariant mMin, mMax, mStep, mValue;
 };
+
+#endif // QGSSLIDER_H
diff --git a/src/providers/oracle/ocispatial/main.h b/src/providers/oracle/ocispatial/main.h
index 83da23141ec6..63cce3816166 100644
--- a/src/providers/oracle/ocispatial/main.h
+++ b/src/providers/oracle/ocispatial/main.h
@@ -41,6 +41,9 @@
 **
 ****************************************************************************/
 
+#ifndef MAIN_H
+#define MAIN_H
+
 #include <qsqldriverplugin.h>
 #include "qsql_ocispatial.h"
 
@@ -54,3 +57,5 @@ class QOCISpatialDriverPlugin : public QSqlDriverPlugin
 
     QSqlDriver *create( const QString & ) override;
 };
+
+#endif // MAIN_H