bug fix in error trace printing

added a class for Token elimination (not done yet)

1 files changed, 5 insertions, 2 deletions

diff --git a/Source/Concurrency/YieldTypeChecker.cs b/Source/Concurrency/YieldTypeChecker.cs
index a848ebeb..086e68fa 100644
--- a/Source/Concurrency/YieldTypeChecker.cs
+++ b/Source/Concurrency/YieldTypeChecker.cs
@@ -63,8 +63,11 @@ namespace Microsoft.Boogie
             String s = "\nBody of " + impl.Proc.Name + " is not yield_type_safe at phase " + currPhaseNum.ToString() + "\n";

             foreach (var move in errorAutomaton.GetMoves())

             {

-                IToken tok = nodeToAbsy[move.SourceState].tok;

-                s += string.Format("{0}({1}, {2})\n", tok.filename, tok.line, tok.col);

+                if (nodeToAbsy.ContainsKey(move.SourceState))

+                {

+                    IToken tok = nodeToAbsy[move.SourceState].tok;

+                    s += string.Format("{0}({1}, {2})\n", tok.filename, tok.line, tok.col);

+                }

             }

             return s;

         }