diff --git a/error.h b/error.h
index 6b5202a4..e6a4984c 100644
--- a/error.h
+++ b/error.h
@@ -14,7 +14,7 @@ class error : public std::exception
   virtual ~error() throw() {}
 
   virtual const char* what() const throw() {
-    return reason;
+    return reason.c_str();
   }
 };