diff --git a/src/cooling/Compton/cooling.h b/src/cooling/Compton/cooling.h
index 77252140d21ca910c0b98c68fbb0e89eea37f6ee..3b5325e9ef25d3153baa9025f00f59b340094776 100644
--- a/src/cooling/Compton/cooling.h
+++ b/src/cooling/Compton/cooling.h
@@ -44,8 +44,7 @@
  * @param restart_flag Are we calling this directly after a restart?
  */
 INLINE static void cooling_update(const struct cosmology* cosmo,
-                                  struct cooling_function_data* cooling,
-                                  const int restart_flag) {
+                                  struct cooling_function_data* cooling) {
   // Add content if required.
 }
 
diff --git a/src/cooling/const_du/cooling.h b/src/cooling/const_du/cooling.h
index 8dc545f5b18cc784274921a226a7d679c367a7e4..0253682aa51993568349df9ebb5e32f42c518dff 100644
--- a/src/cooling/const_du/cooling.h
+++ b/src/cooling/const_du/cooling.h
@@ -54,8 +54,7 @@
  * @param restart_flag Are we calling this directly after a restart?
  */
 INLINE static void cooling_update(const struct cosmology* cosmo,
-                                  struct cooling_function_data* cooling,
-                                  const int restart_flag) {
+                                  struct cooling_function_data* cooling) {
   // Add content if required.
 }
 
diff --git a/src/cooling/const_lambda/cooling.h b/src/cooling/const_lambda/cooling.h
index 09c96413ce0d061c01bc267af46e65ee23d2834f..963723785a1bf85fad4dd9ddbd2eb9927eedf9ea 100644
--- a/src/cooling/const_lambda/cooling.h
+++ b/src/cooling/const_lambda/cooling.h
@@ -53,8 +53,7 @@
  * @param restart_flag Are we calling this directly after a restart?
  */
 INLINE static void cooling_update(const struct cosmology* cosmo,
-                                  struct cooling_function_data* cooling,
-                                  const int restart_flag) {
+                                  struct cooling_function_data* cooling) {
   // Add content if required.
 }