diff --git a/test/fixed_size_queue_tests.cpp b/test/fixed_size_queue_tests.cpp
index 99084661a..0fbfd845a 100644
--- a/test/fixed_size_queue_tests.cpp
+++ b/test/fixed_size_queue_tests.cpp
@@ -44,5 +44,6 @@ int main(int, char**)
     assert(*b++ == 4);
     assert(*b++ == 5);
     assert(b == q.end());
+    return 0;
 }
 
diff --git a/test/owi_st_tests.cpp b/test/owi_st_tests.cpp
index fa4aebb8c..6ae3b3780 100644
--- a/test/owi_st_tests.cpp
+++ b/test/owi_st_tests.cpp
@@ -74,4 +74,5 @@ main()
     assert(c1o1->get_object_id()==1);
 
     std::cout << "Test concluded successfully\n";
+    return 0;
 }
diff --git a/test/while_tests.cpp b/test/while_tests.cpp
index 12fa82154..dbbee9b39 100644
--- a/test/while_tests.cpp
+++ b/test/while_tests.cpp
@@ -194,6 +194,8 @@ main()
     // check wether as_parser<> works:
     while_p('"')['"'];
     do_p['"'].while_p('"');
+
+    return error_count!=0;
 }
 ////////////////////////////////////////////////////////////////////////////////
 // End of File