diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 487f587..13ebfd1 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -102,6 +102,7 @@ boost_test(TYPE run SOURCES std_interop_test9.cpp)
 boost_test(TYPE run SOURCES ec_location_test.cpp)
 
 boost_test(TYPE run SOURCES error_condition_test3.cpp)
+boost_test(TYPE run SOURCES error_code_test2.cpp)
 
 # result
 
diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index bc529f1..0c3cd6c 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -124,6 +124,7 @@ run std_interop_test9.cpp ;
 run ec_location_test.cpp ;
 
 run error_condition_test3.cpp ;
+run error_code_test2.cpp ;
 
 # result
 
diff --git a/test/error_code_test2.cpp b/test/error_code_test2.cpp
new file mode 100644
index 0000000..e4686d4
--- /dev/null
+++ b/test/error_code_test2.cpp
@@ -0,0 +1,94 @@
+// Copyright 2020, 2021 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// http://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/system/error_code.hpp>
+#include <boost/system/generic_category.hpp>
+#include <boost/system/system_category.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+namespace sys = boost::system;
+
+int main()
+{
+    char buffer[ 1024 ];
+
+    sys::error_code ec;
+
+    BOOST_TEST_EQ( ec.value(), 0 );
+    BOOST_TEST( ec.category() == sys::system_category() );
+    BOOST_TEST_EQ( ec.message(), ec.category().message( ec.value() ) );
+    BOOST_TEST_CSTR_EQ( ec.message( buffer, sizeof( buffer ) ), ec.category().message( ec.value(), buffer, sizeof( buffer ) ) );
+    BOOST_TEST( !ec.failed() );
+    BOOST_TEST( !ec );
+
+    BOOST_TEST_EQ( ec.to_string(), std::string( "system:0" ) );
+
+    {
+        sys::error_code ec2( ec );
+
+        BOOST_TEST_EQ( ec2.value(), 0 );
+        BOOST_TEST( ec2.category() == sys::system_category() );
+        BOOST_TEST_EQ( ec2.message(), ec2.category().message( ec2.value() ) );
+        BOOST_TEST_CSTR_EQ( ec2.message( buffer, sizeof( buffer ) ), ec2.category().message( ec2.value(), buffer, sizeof( buffer ) ) );
+        BOOST_TEST( !ec2.failed() );
+        BOOST_TEST( !ec2 );
+
+        BOOST_TEST_EQ( ec, ec2 );
+        BOOST_TEST_NOT( ec != ec2 );
+
+        BOOST_TEST_EQ( ec2.to_string(), std::string( "system:0" ) );
+    }
+
+    {
+        sys::error_code ec2( ec.value(), ec.category() );
+
+        BOOST_TEST_EQ( ec2.value(), 0 );
+        BOOST_TEST( ec2.category() == sys::system_category() );
+        BOOST_TEST_EQ( ec2.message(), ec2.category().message( ec2.value() ) );
+        BOOST_TEST_CSTR_EQ( ec2.message( buffer, sizeof( buffer ) ), ec2.category().message( ec2.value(), buffer, sizeof( buffer ) ) );
+        BOOST_TEST( !ec2.failed() );
+        BOOST_TEST( !ec2 );
+
+        BOOST_TEST_EQ( ec, ec2 );
+        BOOST_TEST_NOT( ec != ec2 );
+
+        BOOST_TEST_EQ( ec2.to_string(), std::string( "system:0" ) );
+    }
+
+    {
+        sys::error_code ec2( 5, sys::generic_category() );
+
+        BOOST_TEST_EQ( ec2.value(), 5 );
+        BOOST_TEST( ec2.category() == sys::generic_category() );
+        BOOST_TEST_EQ( ec2.message(), ec2.category().message( ec2.value() ) );
+        BOOST_TEST_CSTR_EQ( ec2.message( buffer, sizeof( buffer ) ), ec2.category().message( ec2.value(), buffer, sizeof( buffer ) ) );
+        BOOST_TEST( ec2.failed() );
+        BOOST_TEST( ec2 );
+        BOOST_TEST_NOT( !ec2 );
+
+        BOOST_TEST_NE( ec, ec2 );
+        BOOST_TEST( ec != ec2 );
+
+        BOOST_TEST_EQ( ec2.to_string(), std::string( "generic:5" ) );
+    }
+
+    {
+        sys::error_code ec2( 5, sys::system_category() );
+
+        BOOST_TEST_EQ( ec2.value(), 5 );
+        BOOST_TEST( ec2.category() == sys::system_category() );
+        BOOST_TEST_EQ( ec2.message(), ec2.category().message( ec2.value() ) );
+        BOOST_TEST_CSTR_EQ( ec2.message( buffer, sizeof( buffer ) ), ec2.category().message( ec2.value(), buffer, sizeof( buffer ) ) );
+        BOOST_TEST( ec2.failed() );
+        BOOST_TEST( ec2 );
+        BOOST_TEST_NOT( !ec2 );
+
+        BOOST_TEST_NE( ec, ec2 );
+        BOOST_TEST( ec != ec2 );
+
+        BOOST_TEST_EQ( ec2.to_string(), std::string( "system:5" ) );
+    }
+
+    return boost::report_errors();
+}