diff --git a/elab_pexpr.cc b/elab_pexpr.cc
index b2ba09148..9e95f79e8 100644
--- a/elab_pexpr.cc
+++ b/elab_pexpr.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: elab_pexpr.cc,v 1.16 2002/08/12 01:34:59 steve Exp $"
+#ident "$Id: elab_pexpr.cc,v 1.17 2002/11/09 01:40:19 steve Exp $"
 #endif
 
 # include "config.h"
@@ -108,11 +108,6 @@ NetEConcat* PEConcat::elaborate_pexpr(Design*des, NetScope*scope) const
 		       << *ex << endl;
 		  des->errors += 1;
 
-	    } else if (ex->expr_width() == 0) {
-		  cerr << ex->get_line() << ": internal error: "
-		       << "Operand of concatenation has no width: "
-		       << *ex << endl;
-		  des->errors += 1;
 	    }
 
 	    tmp->set(idx, ex);
@@ -222,6 +217,9 @@ NetExpr*PEUnary::elaborate_pexpr (Design*des, NetScope*scope) const
 
 /*
  * $Log: elab_pexpr.cc,v $
+ * Revision 1.17  2002/11/09 01:40:19  steve
+ *  Postpone parameter width check to evaluation.
+ *
  * Revision 1.16  2002/08/12 01:34:59  steve
  *  conditional ident string using autoconfig.
  *
diff --git a/eval_tree.cc b/eval_tree.cc
index 7dd237a97..c1c7afa27 100644
--- a/eval_tree.cc
+++ b/eval_tree.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: eval_tree.cc,v 1.42 2002/10/19 22:59:49 steve Exp $"
+#ident "$Id: eval_tree.cc,v 1.43 2002/11/09 01:40:19 steve Exp $"
 #endif
 
 # include "config.h"
@@ -752,7 +752,13 @@ NetEConst* NetEConcat::eval_tree()
 			     << "operand has indefinite width: "
 			     << *parms_[idx] << endl;
 			local_errors += 1;
+		  } else if (expr->expr_width() == 0) {
+			cerr << expr->get_line() << ": internal error: "
+			     << "Operand of concatenation has no width: "
+			     << *expr << endl;
+			local_errors += 1;
 		  }
+
 		  gap += expr->expr_width();
 	    }
 
@@ -1134,6 +1140,9 @@ NetEConst* NetEUReduce::eval_tree()
 
 /*
  * $Log: eval_tree.cc,v $
+ * Revision 1.43  2002/11/09 01:40:19  steve
+ *  Postpone parameter width check to evaluation.
+ *
  * Revision 1.42  2002/10/19 22:59:49  steve
  *  Redo the parameter vector support to allow
  *  parameter names in range expressions.
diff --git a/net_expr.cc b/net_expr.cc
index 5beb05efb..b7a697d4f 100644
--- a/net_expr.cc
+++ b/net_expr.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: net_expr.cc,v 1.9 2002/11/06 02:25:13 steve Exp $"
+#ident "$Id: net_expr.cc,v 1.10 2002/11/09 01:40:19 steve Exp $"
 #endif
 
 # include  "config.h"
@@ -109,6 +109,11 @@ NetEConcat::~NetEConcat()
 	    delete parms_[idx];
 }
 
+bool NetEConcat::has_width() const
+{
+      return true;
+}
+
 void NetEConcat::set(unsigned idx, NetExpr*e)
 {
       assert(idx < parms_.count());
@@ -237,6 +242,9 @@ bool NetESelect::set_width(unsigned w)
 
 /*
  * $Log: net_expr.cc,v $
+ * Revision 1.10  2002/11/09 01:40:19  steve
+ *  Postpone parameter width check to evaluation.
+ *
  * Revision 1.9  2002/11/06 02:25:13  steve
  *  No need to keep excess width from an
  *  unsigned constant value, if it can
diff --git a/netlist.h b/netlist.h
index db7acdb60..62bcbf9d3 100644
--- a/netlist.h
+++ b/netlist.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: netlist.h,v 1.268 2002/11/02 03:27:52 steve Exp $"
+#ident "$Id: netlist.h,v 1.269 2002/11/09 01:40:19 steve Exp $"
 #endif
 
 /*
@@ -2428,6 +2428,7 @@ class NetEConcat  : public NetExpr {
       NetExpr* parm(unsigned idx) const { return parms_[idx]; }
 
       virtual NexusSet* nex_input();
+      virtual bool has_width() const;
       virtual bool set_width(unsigned w);
       virtual NetEConcat* dup_expr() const;
       virtual NetEConst*  eval_tree();
@@ -3083,6 +3084,9 @@ extern ostream& operator << (ostream&, NetNet::Type);
 
 /*
  * $Log: netlist.h,v $
+ * Revision 1.269  2002/11/09 01:40:19  steve
+ *  Postpone parameter width check to evaluation.
+ *
  * Revision 1.268  2002/11/02 03:27:52  steve
  *  Allow named events to be referenced by
  *  hierarchical names.