Failed spares set use index to own id

Former-commit-id: e4da5bd5d8

src/storage/dft/DFT.cpp

@@ -263,10 +263,10 @@ namespace storm {
                     stream << "\t** " << storm::storage::toChar(state->getElementState(elem->id()));
                     if(elem->isSpareGate()) {
                         size_t useId = state->uses(elem->id());
-                        if(state->isActive(useId)) {
-                            stream << " actively ";
+                        if(useId == elem->id() || state->isActive(useId)) {
+                            stream << "actively ";
                         }
-                        stream << " using " << useId;
+                        stream << "using " << useId;
                     }
                 }
                 stream << std::endl;
@@ -287,8 +287,8 @@ namespace storm {
                     if(elem->isSpareGate()) {
                         stream << "[";
                         size_t useId = state->uses(elem->id());
-                        if(state->isActive(useId)) {
-                            stream << " actively ";
+                        if(useId == elem->id() || state->isActive(useId)) {
+                            stream << "actively ";
                         }
                         stream << "using " << useId << "]";
                     }

src/storage/dft/DFTElements.h

@@ -412,12 +412,12 @@ namespace storm {
             }
 
             /**
-             * Finish failed/failsafe spare gate by activating the children and setting the useIndex to zero.
+             * Finish failed/failsafe spare gate by activating the children and setting the useIndex to the spare id.
              * This prevents multiple fail states with different usages or activations.
              * @param state The current state.
              */
             void finalizeSpare(DFTState<ValueType>& state) const {
-                state.setUses(this->mId, 0);
+                state.setUses(this->mId, this->mId);
                 for (auto child : this->children()) {
                     if (!state.isActive(child->id())) {
                         state.activate(child->id());