diff --git a/lib/System/DynamicLibrary.cpp b/lib/System/DynamicLibrary.cpp
index 056fed0..9bec68e 100644
--- a/lib/System/DynamicLibrary.cpp
+++ b/lib/System/DynamicLibrary.cpp
@@ -107,7 +107,8 @@
     a_handle = lt_dlopenext(filename);
 
   if (a_handle == 0)
-    throw std::string("Can't open :") + filename + ": " + lt_dlerror();
+    throw std::string("Can't open :") +
+          (filename ? filename : "<current process>") + ": " + lt_dlerror();
 
   lt_dlmakeresident(a_handle);