diff --git a/lib-src/libnyquist/nyquist/xlisp/xlimage.c b/lib-src/libnyquist/nyquist/xlisp/xlimage.c
index 2ea6a7950..a23707633 100644
--- a/lib-src/libnyquist/nyquist/xlisp/xlimage.c
+++ b/lib-src/libnyquist/nyquist/xlisp/xlimage.c
@@ -397,7 +397,7 @@ LOCAL OFFTYPE cvoptr(LVAL p)
 
     /* pointer not within any segment */
     xlerror("bad pointer found during image save",p);
-    return (NIL);
+    return ((OFFTYPE)NIL);
 }
 
 #endif