Remember to handle fieldinfo->paramname at sv_dup() time

Author: leonerd

pad.c

@@ -2883,6 +2883,7 @@ Perl_padname_dup(pTHX_ PADNAME *src, CLONE_PARAMS *param)
         dinfo->refcount   = 1;
         dinfo->fieldix    = sinfo->fieldix;
         dinfo->fieldstash = hv_dup_inc(sinfo->fieldstash, param);
+        dinfo->paramname  = sv_dup_inc(sinfo->paramname, param);
 
         PadnameFIELDINFO(dst) = dinfo;
     }