diff --git a/panels/wacom/calibrator/calibrator-gui.h b/panels/wacom/calibrator/calibrator-gui.h
index bf3e84af1..d3301c138 100644
--- a/panels/wacom/calibrator/calibrator-gui.h
+++ b/panels/wacom/calibrator/calibrator-gui.h
@@ -21,11 +21,12 @@
  * THE SOFTWARE.
  */
 
-#ifndef __CALIBRATOR_GUI_H__
-#define __CALIBRATOR_GUI_H__
+#pragma once
 
 #include <gtk/gtk.h>
 
+G_BEGIN_DECLS
+
 /* struct to hold min/max info of the X and Y axis */
 typedef struct
 {
@@ -60,4 +61,5 @@ void calib_area_get_axis (CalibArea *area,
 
 void calib_area_get_padding (CalibArea *area,
                              XYinfo    *padding);
-#endif /* __CALIBRATOR_GUI_H__ */
+
+G_END_DECLS
diff --git a/panels/wacom/calibrator/calibrator.h b/panels/wacom/calibrator/calibrator.h
index 786fd6162..dab7a2fec 100644
--- a/panels/wacom/calibrator/calibrator.h
+++ b/panels/wacom/calibrator/calibrator.h
@@ -21,12 +21,13 @@
  * THE SOFTWARE.
  */
 
-#ifndef _calibrator_h
-#define _calibrator_h
+#pragma once
 
 #include <glib.h>
 #include "calibrator-gui.h"
 
+G_BEGIN_DECLS
+
 /*
  * Number of blocks. We partition the screen into 'num_blocks' x 'num_blocks'
  * rectangles of equal size. We then ask the user to press points that are
@@ -95,4 +96,4 @@ gboolean finish     (struct Calib *c,
                  XYinfo       *new_axis,
                  gboolean         *swap);
 
-#endif /* _calibrator_h */
+G_END_DECLS