diff --git a/src/richtext/richtextbuffer.cpp b/src/richtext/richtextbuffer.cpp
index e8aee90954..5881f6f45c 100644
--- a/src/richtext/richtextbuffer.cpp
+++ b/src/richtext/richtextbuffer.cpp
@@ -12441,6 +12441,7 @@ wxRichTextAttr wxRichTextDrawingContext::GetVirtualAttributes(wxRichTextObject*
         {
             bool success = handler->GetVirtualAttributes(attr, obj);
             wxASSERT(success);
+            wxUnusedVar(success);
         }
 
         node = node->GetNext();