diff --git a/src/rules.cc b/src/rules.cc
index 81e3e767..3136301a 100644
--- a/src/rules.cc
+++ b/src/rules.cc
@@ -103,6 +103,7 @@ int Rules::loadFromUri(const char *uri) {
 
     if (driver->parseFile(uri) == false) {
         m_parserError << driver->m_parserError.str();
+        delete driver;
         return -1;
     }