diff --git a/src/propgrid/property.cpp b/src/propgrid/property.cpp
index d72447cb49..97122b7559 100644
--- a/src/propgrid/property.cpp
+++ b/src/propgrid/property.cpp
@@ -1904,7 +1904,7 @@ wxString wxPGProperty::GetFlagsAsString( FlagType flagsMask ) const
                 s << wxS("|");
             s << fs;
         }
-        a = a << 1;
+        a <<= 1;
     }
 
     return s;