diff --git a/elab_net.cc b/elab_net.cc
index 289f6aefe..fd945b54f 100644
--- a/elab_net.cc
+++ b/elab_net.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: elab_net.cc,v 1.194 2007/01/20 02:10:45 steve Exp $"
+#ident "$Id: elab_net.cc,v 1.195 2007/01/31 04:21:10 steve Exp $"
 #endif
 
 # include "config.h"
@@ -28,6 +28,7 @@
 # include  "compiler.h"
 
 # include  <iostream>
+# include  "ivl_assert.h"
 
 /*
  * This is a state flag that determines whether an elaborate_net must
@@ -1742,9 +1743,9 @@ NetNet* PEIdent::elaborate_net_array_(Design*des, NetScope*scope,
 				      Link::strength_t drive0,
 				      Link::strength_t drive1) const
 {
-      assert(msb_ == 0);
-      assert(lsb_ == 0);
-      assert(idx_.size() == 1);
+      ivl_assert(*this, msb_ == 0);
+      ivl_assert(*this, lsb_ == 0);
+      ivl_assert(*this, idx_.size() == 1);
 
       NetExpr*index_ex = elab_and_eval(des, scope, idx_[0], -1);
       if (index_ex == 0)
@@ -2894,6 +2895,9 @@ NetNet* PEUnary::elaborate_net(Design*des, NetScope*scope,
 
 /*
  * $Log: elab_net.cc,v $
+ * Revision 1.195  2007/01/31 04:21:10  steve
+ *  Add method to bind assertions to verilog source lines.
+ *
  * Revision 1.194  2007/01/20 02:10:45  steve
  *  Get argument widths right for shift results.
  *
diff --git a/ivl_assert.h b/ivl_assert.h
new file mode 100644
index 000000000..503e148b6
--- /dev/null
+++ b/ivl_assert.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2007 Stephen Williams (steve@icarus.com)
+ *
+ *    This source code is free software; you can redistribute it
+ *    and/or modify it in source code form under the terms of the GNU
+ *    General Public License as published by the Free Software
+ *    Foundation; either version 2 of the License, or (at your option)
+ *    any later version.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+#ifdef HAVE_CVS_IDENT
+#ident "$Id: ivl_assert.h,v 1.1 2007/01/31 04:21:10 steve Exp $"
+#endif
+
+#ifndef __ivl_assert_h
+#define __ivl_assert_h
+
+# include  <assert.h>
+
+#define ivl_assert(tok, expression)  \
+      do {			    \
+	    if (! (expression))     \
+		  __ivl_assert(#expression, tok, __FILE__, __LINE__);	\
+      } while(0)
+
+#define __ivl_assert(expression, tok, file, line)  \
+      do { \
+	    cerr << (tok).get_line() << ": assert: " \
+		 << file << ":" << line \
+		 << ": failed assertion " << (expression) << endl; \
+	    abort(); \
+      } while(0)
+
+
+#endif