--- ./lib/core/src/perl/RefHash.xs.orig	2013-08-14 13:17:10.000000000 -0600
+++ ./lib/core/src/perl/RefHash.xs	2014-01-08 13:50:43.368174796 -0700
@@ -89,7 +89,7 @@ SV* ref2key(SV *keysv, tmp_keysv *tmp_ke
    }                                                                    \
 } STMT_END
 
-static char err_ref[]="Reference as a key in a normal hash";
+static const char err_ref[]="Reference as a key in a normal hash";
 
 static inline
 int ref_key_allowed(HV *class)