diff --git a/dix/colormap_priv.h b/dix/colormap_priv.h
index 22d80be6d..ce18ce29b 100644
--- a/dix/colormap_priv.h
+++ b/dix/colormap_priv.h
@@ -108,4 +108,7 @@ int StoreColors(ColormapPtr pmap, int count, xColorItem * defs, ClientPtr client
 
 int IsMapInstalled(Colormap map, WindowPtr pWin);
 
+/* only exported for glx, but should not be used by external drivers */
+_X_EXPORT Bool ResizeVisualArray(ScreenPtr pScreen, int new_vis_count, DepthPtr depth);
+
 #endif /* _XSERVER_DIX_COLORMAP_PRIV_H */
diff --git a/glx/glxscreens.c b/glx/glxscreens.c
index 5321fdac5..e5c5f974c 100644
--- a/glx/glxscreens.c
+++ b/glx/glxscreens.c
@@ -32,8 +32,11 @@
 
 #include "dix/screen_hooks_priv.h"
 
-#include <GL/glxtokens.h>
 #include <string.h>
+#include <GL/glxtokens.h>
+
+#include "dix/colormap_priv.h"
+
 #include <windowstr.h>
 #include <os.h>
 
diff --git a/include/colormap.h b/include/colormap.h
index 216a4c932..48ae0d649 100644
--- a/include/colormap.h
+++ b/include/colormap.h
@@ -55,8 +55,4 @@ SOFTWARE.
 
 typedef CARD32 Pixel;
 
-extern _X_EXPORT Bool ResizeVisualArray(ScreenPtr /* pScreen */ ,
-                                        int /* new_vis_count */ ,
-                                        DepthPtr /* depth */ );
-
 #endif                          /* CMAP_H */