diff --git a/test/throw_from_library_test.cpp b/test/throw_from_library_test.cpp
index 8690a8b..a3dc073 100644
--- a/test/throw_from_library_test.cpp
+++ b/test/throw_from_library_test.cpp
@@ -93,7 +93,7 @@ void test_throw_line()
     {
         boost::source_location loc = boost::get_throw_location( x );
 
-        BOOST_TEST_NE( loc.line(), 0 );
+        BOOST_TEST_NE( loc.line(), 0u );
     }
     catch( ... )
     {
diff --git a/test/throw_with_location_test2.cpp b/test/throw_with_location_test2.cpp
index d52a3cd..74fb854 100644
--- a/test/throw_with_location_test2.cpp
+++ b/test/throw_with_location_test2.cpp
@@ -31,7 +31,7 @@ int main()
         // So we can't be more specific in testing it.
 
         BOOST_TEST_CSTR_NE( loc.file_name(), "" );
-        BOOST_TEST_NE( loc.line(), 0 );
+        BOOST_TEST_NE( loc.line(), 0u );
     }
     catch( ... )
     {
diff --git a/test/throw_with_location_test3.cpp b/test/throw_with_location_test3.cpp
index c37071f..b8271fa 100644
--- a/test/throw_with_location_test3.cpp
+++ b/test/throw_with_location_test3.cpp
@@ -25,8 +25,8 @@ int main()
 
         BOOST_TEST_CSTR_EQ( loc.file_name(), "" );
         BOOST_TEST_CSTR_EQ( loc.function_name(), "" );
-        BOOST_TEST_EQ( loc.line(), 0 );
-        BOOST_TEST_EQ( loc.column(), 0 );
+        BOOST_TEST_EQ( loc.line(), 0u );
+        BOOST_TEST_EQ( loc.column(), 0u );
     }
 
     return boost::report_errors();