anchor.diff:      while (parentClass >= 0) {
         vcm[parentClass] = <int>[];
         for (int j = 0, n = classMethods[parentClass].length; j < n; j++) {
  -        if (rollDice(8)) {
  +        // Call methods are presently always already overriden, so we
  +        // shouldn't override them here.
  +        if (rollDice(8) && !(classMethods[parentClass][j] is CallMethod)) {
             currentClass = parentClass;
             currentMethod = j;
             classMethods[parentClass][j].emit();
  
positive.code: // Version of DartFuzz. Increase this each time changes are made
  // to preserve the property that a given version of DartFuzz yields
  // the same fuzzed program for a deterministic random seed.
  const String version = '1.73';
  
  // Restriction on statements and expressions.
  const int stmtDepth = 1;
  
negative.code:         namePrefix: methodName);
      classFields = fillTypes2(limit2: numClasses, limit1: numLocalVars);
      final int numClassMethods = 1 + numClasses - classFields.length;
      classMethods = getClassMethods(classFields.length, numClassMethods,
          numMethodParams, fillTypes1(limit: numMethodParams));
      virtualClassMethods = <Map<int, List<int>>>[];
      classParents = <int>[];
      // Setup optional ffi methods and types.
  