diff --git a/examples/boing.c b/examples/boing.c
index d3b34172..6dbca066 100644
--- a/examples/boing.c
+++ b/examples/boing.c
@@ -43,7 +43,6 @@
 void init( void );
 void display( void );
 void reshape( GLFWwindow window, int w, int h );
-int window_close_callback(GLFWwindow window);
 void DrawBoingBall( void );
 void BounceBall( double dt );
 void DrawBoingBallBand( GLfloat long_lo, GLfloat long_hi );
@@ -250,7 +249,7 @@ void reshape( GLFWwindow window, int w, int h )
 /*****************************************************************************
  * Window close callback
  *****************************************************************************/
-int window_close_callback(GLFWwindow window)
+static int window_close_callback(GLFWwindow window)
 {
     running = GL_FALSE;
     return GL_TRUE;
diff --git a/examples/gears.c b/examples/gears.c
index 4ce68ab6..9d9c7d60 100644
--- a/examples/gears.c
+++ b/examples/gears.c
@@ -268,7 +268,7 @@ void reshape( GLFWwindow window, int width, int height )
 
 
 /* close callback */
-int window_close_callback(GLFWwindow window)
+static int window_close_callback(GLFWwindow window)
 {
     running = 0;
     return GL_TRUE;