diff --git a/MagickCore/cache-private.h b/MagickCore/cache-private.h
index 9b89131..3b80ee6 100644
--- a/MagickCore/cache-private.h
+++ b/MagickCore/cache-private.h
@@ -116,6 +116,9 @@
     *cache,
     *pixels;
 
+  MagickBooleanType
+    is_authentic_pixels;
+
   void
     *metacontent;