Fix double free bug when server is shut down

Thanks @oleastre

diff --git a/src/mapgen.h b/src/mapgen.h
index cfecb3206ac56d4fd772085fde5fde0da23a6855..cf2120a7a2843f98398b7effc213feee79b1cae3 100644 (file)
--- a/src/mapgen.h
+++ b/src/mapgen.h
@@ -136,6 +136,7 @@ struct MapgenFactory {
 
 class GenElement {
 public:
+       virtual ~GenElement() {}
        u32 id;
        std::string name;
 };