diff --git a/CMakeLists.txt b/CMakeLists.txt
index e9b6dca0..013a5d90 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -399,7 +399,6 @@ set(STA_TCL_FILES
   dcalc/DelayCalc.tcl
   parasitics/Parasitics.tcl
   sdf/Sdf.tcl
-  tcl/Compatibility.tcl
   verilog/Verilog.tcl
   )
 
diff --git a/search/Sta.cc b/search/Sta.cc
index 4f0d2e5c..58d11153 100644
--- a/search/Sta.cc
+++ b/search/Sta.cc
@@ -3151,14 +3151,14 @@ Sta::pathDcalcAnalysisPt(Path *path)
 }
 
 Vertex *
-Sta::maxPathCountVertex() const
+Sta::maxArrivalCountVertex() const
 {
   Vertex *max_vertex = nullptr;
   VertexIndex max_count = 0;
   VertexIterator vertex_iter(graph_);
   while (vertex_iter.hasNext()) {
     Vertex *vertex = vertex_iter.next();
-    VertexIndex count = vertexPathCount(vertex);
+    VertexIndex count = vertexArrivalCount(vertex);
     if (count > max_count) {
       max_count = count;
       max_vertex = vertex;
@@ -3168,19 +3168,23 @@ Sta::maxPathCountVertex() const
 }
 
 int
-Sta::vertexPathCount(Vertex  *vertex) const
+Sta::vertexArrivalCount(Vertex  *vertex) const
 {
-  return search_->tagGroup(vertex)->arrivalCount();
+  auto tag_group = search_->tagGroup(vertex);
+  if (tag_group)
+    return tag_group->arrivalCount();
+  else
+    return 0;
 }
 
 int
-Sta::pathCount() const
+Sta::arrivalCount() const
 {
   int count = 0;
   VertexIterator vertex_iter(graph_);
   while (vertex_iter.hasNext()) {
     Vertex *vertex = vertex_iter.next();
-    count += vertexPathCount(vertex);
+    count += vertexArrivalCount(vertex);
   }
   return count;
 }
diff --git a/search/Sta.hh b/search/Sta.hh
index 125c96ef..74d9b92a 100644
--- a/search/Sta.hh
+++ b/search/Sta.hh
@@ -1026,9 +1026,9 @@ public:
   TagIndex tagCount() const;
   TagGroupIndex tagGroupCount() const;
   int clkInfoCount() const;
-  int pathCount() const;
-  int vertexPathCount(Vertex  *vertex) const;
-  Vertex *maxPathCountVertex() const;
+  int arrivalCount() const;
+  int vertexArrivalCount(Vertex  *vertex) const;
+  Vertex *maxArrivalCountVertex() const;
 
   LogicValue simLogicValue(const Pin *pin);
   // Iterator for instances sorted by max driver pin slew.
diff --git a/tcl/StaTcl.i b/tcl/StaTcl.i
index e51fcc14..426ea1a5 100644
--- a/tcl/StaTcl.i
+++ b/tcl/StaTcl.i
@@ -5070,9 +5070,9 @@ clk_info_count()
 }
 
 int
-path_count()
+arrival_count()
 {
-  return Sta::sta()->pathCount();
+  return Sta::sta()->arrivalCount();
 }
 
 void