Avoid all other warnings

ColoredSquare.c

@@ -70,14 +70,20 @@ void ColoredSquare_set_color (ColoredSquare *this, int color)
 ColoredSquare* ColoredSquare_new (double a, int color)
 {
   static ColoredSquare_interface vtable =
+    {
+      {
+        {
           {
             (void* (*) (void *)) ColoredSquare_clone,
-      (void (*) (void *)) Square_destroy,
+            (void (*) (void *)) Square_destroy
+          },
           (const char* (*) (Figure *)) ColoredSquare_type,
           (void (*) (Figure *)) ColoredSquare_draw,
-      (double (*) (Figure *)) Square_area,
+          (double (*) (Figure *)) Square_area
+        },
         Square_resize,
-      Square_diag_length,
+        Square_diag_length
+      },
       ColoredSquare_set_color
     };
   ColoredSquare *square = malloc (sizeof (*square));

Square.c

@@ -101,12 +101,16 @@ double Square_diag_length (Square *this)
 Square* Square_new (double a)
 {
   static Square_interface vtable =
+    {
+      {
         {
           (void* (*) (void *)) Square_clone,
-      (void (*) (void *)) Square_destroy,
+          (void (*) (void *)) Square_destroy
+        },
         (const char* (*) (Figure *)) Square_type,
         (void (*) (Figure *)) Square_draw,
-      (double (*) (Figure *)) Square_area,
+        (double (*) (Figure *)) Square_area
+      },
       Square_resize,
       Square_diag_length
     };

main.c

@@ -3,7 +3,7 @@
 
 #include "ColoredSquare.h"
 
-int main (int argc, char *argv[])
+int main (void)
 {
   unsigned long i = 0;
   Figure *fig[3];