diff --git a/src/devices/screen.h b/src/devices/screen.h
index 9a37e2a..9d3e7e7 100644
--- a/src/devices/screen.h
+++ b/src/devices/screen.h
@@ -22,7 +22,7 @@ void screen_change(int x1, int y1, int x2, int y2);
 void screen_fill(Uint8 *layer, int color);
 void screen_palette(void);
 void screen_resize(Uint16 width, Uint16 height, int scale);
-void screen_redraw();
+void screen_redraw(void);
 
 Uint8 screen_dei(Uxn *u, Uint8 addr);
 void screen_deo(Uxn *u, Uint8 addr);
diff --git a/src/devices/system.h b/src/devices/system.h
index 8b0d7c1..882ff66 100644
--- a/src/devices/system.h
+++ b/src/devices/system.h
@@ -19,4 +19,4 @@ int system_boot(Uint8 *ram, char *rom);
 Uint8 system_dei(Uxn *u, Uint8 addr);
 void system_deo(Uxn *u, Uint8 addr);
 
-extern Uxn bios;
\ No newline at end of file
+extern Uxn bios;