diff --git a/PDT/Matcher.tcc b/PDT/Matcher.tcc
--- a/PDT/Matcher.tcc
+++ b/PDT/Matcher.tcc
@@ -1,60 +1,60 @@
 // -*- C++ -*-
 //
 // Matcher.tcc is a part of ThePEG - Toolkit for HEP Event Generation
 // Copyright (C) 1999-2017 Leif Lonnblad
 //
 // ThePEG is licenced under version 3 of the GPL, see COPYING for details.
 // Please respect the MCnet academic guidelines, see GUIDELINES for details.
 //
 //
 // This is the implementation of the non-inlined templated member
 // functions of the Matcher class.
 //
 
 namespace ThePEG {
 
 template <class T>
 Matcher<T>::~Matcher() {
-  assert ( initMatcher.check() );
+  if( !initMatcher.check() ){assert(false)};
 } 
 
 template <class T>
 NoPIOClassDescription< Matcher<T> > Matcher<T>::initMatcher;
 
 template <class T>
 PMPtr Matcher<T>::Create(const string & newName, string antiName) {
   typedef typename Ptr< Matcher<T> >::pointer MatcherPtr;
   typedef typename Ptr< Matcher<typename T::CC> >::pointer AMatcherPtr;
   PMPtr pm = new_ptr<MatcherPtr>();
   registerRepository(pm, newName);
   if ( typeid(T) == typeid(typename T::CC) ) return pm;
   if ( antiName.empty() ) antiName = newName + "~";
   PMPtr apm = new_ptr<AMatcherPtr>();
   setCC(pm, apm);
   registerRepository(apm, antiName);
   return pm;
 }
 
 template <class T>
 PMPtr Matcher<T>::pmclone() const {
   return new_ptr(*this);
 }
 
 template <class T>
 IBPtr Matcher<T>::clone() const {
   return pmclone();
 }
 
 template <class T>
 IBPtr Matcher<T>::fullclone() const {
   PMPtr pm = pmclone();
   registerRepository(pm);
   if ( !CC() ) return pm;
   PMPtr apm = CC()->pmclone();
   setCC(pm, apm);
   registerRepository(apm);
   return pm;
 }
 
 }