diff --git a/Compiler/BackEnd/HpcOmTaskGraph.mo b/Compiler/BackEnd/HpcOmTaskGraph.mo
index 068fcdc1dae..02b9c7b1044 100644
--- a/Compiler/BackEnd/HpcOmTaskGraph.mo
+++ b/Compiler/BackEnd/HpcOmTaskGraph.mo
@@ -1623,6 +1623,9 @@ algorithm
       list<Integer> cutNodes,odeNodes;
       array<Integer> odeMap;
       list<list<Integer>> graphTmpLst;
+    case(_,{-1},_)
+      equation
+      then (graphIn,{});
     case(_,_,_)
       equation
         // remove the algebraic branches