diff --git a/elab_scope.cc b/elab_scope.cc
index 00f564b10..596ccf028 100644
--- a/elab_scope.cc
+++ b/elab_scope.cc
@@ -22,6 +22,7 @@
 # include  "netmisc.h"
 # include  <cstring>
 # include  <iostream>
+# include  <cstdlib>
 # include  <stdio.h>
 
 /*
diff --git a/net_design.cc b/net_design.cc
index d180f7160..4640003b2 100644
--- a/net_design.cc
+++ b/net_design.cc
@@ -20,6 +20,7 @@
 # include "config.h"
 
 # include  <iostream>
+# include  <cstdlib>
 
 /*
  * This source file contains all the implementations of the Design
diff --git a/net_scope.cc b/net_scope.cc
index 59cdb1790..4425a2a49 100644
--- a/net_scope.cc
+++ b/net_scope.cc
@@ -22,6 +22,7 @@
 
 # include  "netlist.h"
 # include  <cstring>
+# include  <cstdlib>
 # include  <sstream>
 # include  "ivl_assert.h"
 
@@ -218,7 +219,7 @@ map<perm_string,NetScope::param_expr_t>::iterator NetScope::find_parameter(perm_
       if (idx != localparams.end())
 	    return idx;
 
-      return 0;
+      return (map<perm_string,param_expr_t>::iterator) 0;
 }
 
 NetScope::TYPE NetScope::type() const