diff --git a/libsrc/dummy2.cpp b/libsrc/dummy2.cpp
new file mode 100644
index 00000000..dda00e51
--- /dev/null
+++ b/libsrc/dummy2.cpp
@@ -0,0 +1,4 @@
+/* mac os x libtool needs to links libraries containing c++ (eg. cimg) with 
+ * g++ ... force this with a dummy c++ file at the top level
+ */
+const int im__dummy_value = 42;