diff --git a/config.c b/config.c
index f44025b..8a5fee6 100644
--- a/config.c
+++ b/config.c
@@ -6,7 +6,7 @@
 #include "zathura.h"
 
 void
-config_load_default()
+config_load_default(void)
 {
   if(!Zathura.UI.session)
     return;
diff --git a/config.h b/config.h
index f9f46b8..7b8293b 100644
--- a/config.h
+++ b/config.h
@@ -3,6 +3,6 @@
 #ifndef CONFIG_H
 #define CONFIG_H
 
-void config_load_default();
+void config_load_default(void);
 
 #endif // CONFIG_H