diff --git a/rtgui/adjuster.cc b/rtgui/adjuster.cc
index bbd6e76cf..f0e53fbbf 100644
--- a/rtgui/adjuster.cc
+++ b/rtgui/adjuster.cc
@@ -17,7 +17,7 @@
  *  along with RawTherapee.  If not, see <http://www.gnu.org/licenses/>.
  */
 #include "adjuster.h"
-#include <sigc++/class_slot.h>
+#include <sigc++/slot.h>
 #include <cmath>
 #include "multilangmgr.h"
 #include "../rtengine/rtengine.h"
diff --git a/rtgui/preferences.cc b/rtgui/preferences.cc
index 9c0918189..141ad35d3 100644
--- a/rtgui/preferences.cc
+++ b/rtgui/preferences.cc
@@ -16,7 +16,7 @@
  *  You should have received a copy of the GNU General Public License
  *  along with RawTherapee.  If not, see <http://www.gnu.org/licenses/>.
  */
-#include <sigc++/class_slot.h>
+#include <sigc++/slot.h>
 #include "preferences.h"
 #include "multilangmgr.h"
 #include "splash.h"
diff --git a/rtgui/thresholdadjuster.cc b/rtgui/thresholdadjuster.cc
index a7e21a26d..800f6edf5 100644
--- a/rtgui/thresholdadjuster.cc
+++ b/rtgui/thresholdadjuster.cc
@@ -17,7 +17,7 @@
  *  along with RawTherapee.  If not, see <http://www.gnu.org/licenses/>.
  */
 #include "thresholdadjuster.h"
-#include <sigc++/class_slot.h>
+#include <sigc++/slot.h>
 #include <cmath>
 #include "multilangmgr.h"
 #include "../rtengine/rtengine.h"
diff --git a/rtgui/tonecurve.cc b/rtgui/tonecurve.cc
index 770652430..799513c2a 100644
--- a/rtgui/tonecurve.cc
+++ b/rtgui/tonecurve.cc
@@ -18,7 +18,7 @@
  */
 #include "tonecurve.h"
 #include "adjuster.h"
-#include <sigc++/class_slot.h>
+#include <sigc++/slot.h>
 #include <iomanip>
 #include "ppversion.h"
 #include "edit.h"