diff --git a/ChangeLog b/ChangeLog
index 29ba18febd..8bbf41ad02 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Sat Dec 29 21:51:30 2012  Shugo Maeda  <shugo@ruby-lang.org>
+
+	* ext/curses/curses.c (window_cury, window_curx, window_maxy,
+	  window_maxx, window_begy, window_begx): use RB_UNUSED_VAR()
+	  to suppress unused-but-set-variable warnings.
+
 Sat Dec 29 16:45:00 2012  Zachary Scott  <zachary@zacharyscott.net>
 
 	* iseq.c (RubyVM::InstructionSequence): rdoc formatting
diff --git a/ext/curses/curses.c b/ext/curses/curses.c
index a2ddb6a1ec..175e32cff9 100644
--- a/ext/curses/curses.c
+++ b/ext/curses/curses.c
@@ -1663,11 +1663,10 @@ static VALUE
 window_cury(VALUE obj)
 {
     struct windata *winp;
-    int x, y;
+    int RB_UNUSED_VAR(x), y;
 
     GetWINDOW(obj, winp);
     getyx(winp->window, y, x);
-    (void)x;
     return INT2FIX(y);
 }
 
@@ -1680,11 +1679,10 @@ static VALUE
 window_curx(VALUE obj)
 {
     struct windata *winp;
-    int x, y;
+    int x, RB_UNUSED_VAR(y);
 
     GetWINDOW(obj, winp);
     getyx(winp->window, y, x);
-    (void)y;
     return INT2FIX(x);
 }
 
@@ -1705,7 +1703,6 @@ window_maxy(VALUE obj)
     {
 	int x, y;
 	getmaxyx(winp->window, y, x);
-	(void)x;
 	return INT2FIX(y);
     }
 #else
@@ -1730,7 +1727,6 @@ window_maxx(VALUE obj)
     {
 	int x, y;
 	getmaxyx(winp->window, y, x);
-	(void)y;
 	return INT2FIX(x);
     }
 #else
@@ -1747,12 +1743,11 @@ static VALUE
 window_begy(VALUE obj)
 {
     struct windata *winp;
-    int x, y;
+    int RB_UNUSED_VAR(x), y;
 
     GetWINDOW(obj, winp);
 #ifdef getbegyx
     getbegyx(winp->window, y, x);
-    (void)x;
 #else
     y = winp->window->_begy;
 #endif
@@ -1768,12 +1763,11 @@ static VALUE
 window_begx(VALUE obj)
 {
     struct windata *winp;
-    int x, y;
+    int x, RB_UNUSED_VAR(y);
 
     GetWINDOW(obj, winp);
 #ifdef getbegyx
     getbegyx(winp->window, y, x);
-    (void)y;
 #else
     x = winp->window->_begx;
 #endif