diff --git a/src/Makefile b/src/Makefile
index c1558d4..b23af1d 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -1,5 +1,6 @@
 OBJS=main.o sysinput.o fbinit.o fbprimitive.o log.o gpio.o msg_queue.o time_func.o config.o splash.o
 LIBS=-lbcm2835 -lpthread
+CFLAGS=-g
 
 upiwin: $(OBJS)
 	gcc -o upiwin $(OBJS) $(LIBS)
diff --git a/src/config.c b/src/config.c
index 89cdbfc..4b6dd20 100644
--- a/src/config.c
+++ b/src/config.c
@@ -46,8 +46,9 @@ static void run_exit_funcs(void)
   {
     p = exitfuncs;
     exitfuncs = p->next;
-    for (i = p->num_funcs - 1; i >= 0; i++)
-      (*(p->funcs[i]))();
+    for (i = p->num_funcs - 1; i >= 0; i--)
+      if (p->funcs[i])
+        (*(p->funcs[i]))();
     free(p);
   }
 }
diff --git a/src/fbprimitive.c b/src/fbprimitive.c
index 2292f48..805dcd4 100644
--- a/src/fbprimitive.c
+++ b/src/fbprimitive.c
@@ -73,10 +73,10 @@ void Fb_line(INT32 x1, INT32 y1, INT32 x2, INT32 y2, UINT16 color, BOOL xor)
 
 void Fb_rectangle(INT32 x1, INT32 y1, INT32 x2, INT32 y2, UINT16 color, BOOL xor)
 {
-  FB_line(x1, y1, x2, y1, color, xor);
-  FB_line(x2, y1 + 1, x2, y2 - 1, color, xor);
-  FB_line(x1, y2, x2, y2, color, xor);
-  FB_line(x1, y1 + 1, x1, y2 - 1, color, xor);
+  Fb_line(x1, y1, x2, y1, color, xor);
+  Fb_line(x2, y1 + 1, x2, y2 - 1, color, xor);
+  Fb_line(x1, y2, x2, y2, color, xor);
+  Fb_line(x1, y1 + 1, x1, y2 - 1, color, xor);
 }
 
 void Fb_filled_rectangle(INT32 x1, INT32 y1, INT32 x2, INT32 y2, UINT16 color, BOOL xor)
diff --git a/src/main.c b/src/main.c
index bd939e9..414f931 100644
--- a/src/main.c
+++ b/src/main.c
@@ -14,10 +14,10 @@ static void do_draw(void)
 {
   Fb_filled_rectangle(10, 10, 50, 50, FBPRIMCLR_RED, FALSE);
   Fb_filled_rectangle(60, 10, 100, 50, FBPRIMCLR_GREEN, FALSE);
-  Fb_filled_rectangle(110, 10, 160, 50, FBPRIMCLR_BLUE, FALSE);
+  Fb_filled_rectangle(110, 10, 150, 50, FBPRIMCLR_BLUE, FALSE);
   Fb_filled_rectangle(10, 60, 50, 100, FBPRIMCLR_CYAN, FALSE);
   Fb_filled_rectangle(60, 60, 100, 100, FBPRIMCLR_MAGENTA, FALSE);
-  Fb_filled_rectangle(110, 60, 160, 100, FBPRIMCLR_YELLOW, FALSE);
+  Fb_filled_rectangle(110, 60, 150, 100, FBPRIMCLR_YELLOW, FALSE);
 }
 
 int main(int argc, char *argv[])