diff --git a/MagickCore/cache-private.h b/MagickCore/cache-private.h
index 58bebe8..9cb0379 100644
--- a/MagickCore/cache-private.h
+++ b/MagickCore/cache-private.h
@@ -249,7 +249,7 @@
 
 extern MagickPrivate VirtualPixelMethod
   GetPixelCacheVirtualMethod(const Image *),
-  SetPixelCacheVirtualMethod(const Image *,const VirtualPixelMethod);
+  SetPixelCacheVirtualMethod(Image *,const VirtualPixelMethod,ExceptionInfo *);
 
 extern MagickPrivate void
   CacheComponentTerminus(void),