Fix compiler warnings (#808)

Signed-off-by: Steve Peters <[email protected]>

src/FrameSemantics.cc

@@ -284,7 +284,7 @@ static Errors resolveModelPoseWithPlacementFrame(
 
 /////////////////////////////////////////////////
 Errors buildFrameAttachedToGraph(
-    ScopedGraph<FrameAttachedToGraph> &_out, const Model *_model, bool _isRoot)
+    ScopedGraph<FrameAttachedToGraph> &_out, const Model *_model, bool)
 {
   Errors errors;
 
@@ -313,22 +313,6 @@ Errors buildFrameAttachedToGraph(
 
   const std::string scopeContextName = "__model__";
 
-  auto rootId = ignition::math::graph::kNullId;
-  if (_isRoot)
-  {
-    // The __root__ vertex identifies the scope that contains a root level
-    // model. In the PoseRelativeTo graph, this vertex is connected to the model
-    // with an edge that holds the value of //model/pose. However, in the
-    // FrameAttachedTo graph, the vertex is disconnected because nothing is
-    // attached to it. Since only links and static models are allowed to be
-    // disconnected in this graph, the STATIC_MODEL was chosen as its frame
-    // type. A different frame type could potentially be used, but that adds
-    // more complexity to the validateFrameAttachedToGraph code.
-    _out = _out.AddScopeVertex(
-        "", "__root__", scopeContextName, sdf::FrameType::STATIC_MODEL);
-    rootId = _out.ScopeVertexId();
-  }
-
   const auto modelId = _out.AddVertex(_model->Name(), frameType).Id();
 
   auto outModel = _out.AddScopeVertex(

src/World.cc

@@ -216,7 +216,7 @@ Errors World::Load(sdf::ElementPtr _sdf, const ParserConfig &_config)
 
   for (const auto &ifaceModelPair : this->dataPtr->interfaceModels)
   {
-    frameNames.insert(ifaceModelPair.second->Name()).second;
+    frameNames.insert(ifaceModelPair.second->Name());
   }
 
   // Load all the physics.