Work around for DeviceAttribute extraction issue

AttributeCombiner.cpp

@@ -944,17 +944,21 @@ void AttributeCombiner::add_dynamic_commands()
 
         for (int i = 0; i < nbDev; i++) {
             for (int j = 0; j < nbAtt; j++) {
-                if (!arl[j][i].has_failed() && !arl[j][i].get_data().is_empty() && arl[j][i].group_element_enabled()) {
+                if (!arl[j][i].has_failed() && arl[j][i].group_element_enabled()) {
                     vector<inType> val;
                     arl[j][i] >> val;
-                    if (firstValue) {
+                    if( val.size()>0 ) {
+                      if (firstValue) {
                         value = val[0];
-                        if(item->rwType == Tango::READ_WRITE){
-                            setPoint = val[1];
+                        if (item->rwType == Tango::READ_WRITE) {
+                          setPoint = val[1];
                         }
                         firstValue = false;
-                    } else {
+                      } else {
                         allEqual = allEqual && (val[0] == value);
+                      }
+                    } else {
+                      allEqual = false;
                     }
                 } else {
                     if (arl[j][i].has_failed() && arl[j][i].group_element_enabled()) {
@@ -1149,18 +1153,22 @@ void AttributeCombiner::add_dynamic_commands()
       for (int i = 0; i < nbDev; i++) {
 
         for (int j = 0; j < nbAtt; j++) {
-          if (arl[j][i].has_failed() || arl[j][i].get_data().is_empty()) {
+          if (arl[j][i].has_failed()) {
             readVal[i * nbAtt + j] = invalid;
             if (isRW) readSetPoint[i * nbAtt + j] = invalid;
-	    if(arl[j][i].has_failed())
-              addError(i, arl[j][i]);
+            addError(i, arl[j][i]);
           } else {
             if (arl[j][i].group_element_enabled()) {
               if (item->type != Tango::DEV_STATE && isRW) {
                 vector<inType> v;
                 arl[j][i] >> v;
-                readVal[i * nbAtt + j] = (outType) v[0];
-                readSetPoint[i * nbAtt + j] = (outType) v[1];
+                if(v.size()>0) {
+                  readVal[i * nbAtt + j] = (outType) v[0];
+                  readSetPoint[i * nbAtt + j] = (outType) v[1];
+                } else {
+                  readVal[i * nbAtt + j] = invalid;
+                  if (isRW) readSetPoint[i * nbAtt + j] = invalid;
+                }
               } else {
                 inType v;
                 arl[j][i] >> v;