diff --git a/libs/gst/control/dparammanager.h b/libs/gst/control/dparammanager.h
index ec11631b6d..c3277e75cb 100644
--- a/libs/gst/control/dparammanager.h
+++ b/libs/gst/control/dparammanager.h
@@ -136,7 +136,7 @@ struct _GstDParamAsyncToUpdate {
 
 #define GST_DPMAN_CALLBACK_UPDATE(dpwrap, value) ((dpwrap->update_func)(value, dpwrap->update_data))
 
-void _gst_dpman_initialize();
+void _gst_dpman_initialize(void);
 GType gst_dpman_get_type (void);
 GstDParamManager* gst_dpman_new (gchar *name, GstElement *parent);
 void gst_dpman_set_parent (GstDParamManager *dpman, GstElement *parent);
diff --git a/libs/gst/control/unitconvert.h b/libs/gst/control/unitconvert.h
index c0836193aa..3acea459d0 100644
--- a/libs/gst/control/unitconvert.h
+++ b/libs/gst/control/unitconvert.h
@@ -54,7 +54,7 @@ struct _GstUnitConvertClass {
 	/* signal callbacks */
 };
 
-GstUnitConvert* gst_unitconv_new ();
+GstUnitConvert* gst_unitconv_new (void);
 void _gst_unitconv_initialize (void);
 
 gboolean gst_unitconv_set_convert_units(GstUnitConvert *unitconv, gchar *from_unit_named, gchar *to_unit_named);
diff --git a/tests/lat.c b/tests/lat.c
index bccfddfdb9..12ce41a9f1 100644
--- a/tests/lat.c
+++ b/tests/lat.c
@@ -54,7 +54,7 @@ GstElement *identity_add(GstPipeline *pipeline, GstElement *first, int count) {
   return last;
 }
 
-GstElement *fakesrc() {
+GstElement *fakesrc(void) {
   GstElement *src;
 
   src = gst_element_factory_make("fakesrc","src");
@@ -67,7 +67,7 @@ GstElement *fakesrc() {
   return src;
 }
 
-GstElement *fakesink() {
+GstElement *fakesink(void) {
   GstElement *sink;
 
   sink = gst_element_factory_make("fakesink","fakesink");