Fixed possible GC-issue when loadable extensions are unavailable

Author: mmottl

lib/sqlite3.ml

@@ -222,7 +222,7 @@ external clear_bindings : stmt -> Rc.t = "caml_sqlite3_clear_bindings"
 external busy_timeout : db -> int -> unit = "caml_sqlite3_busy_timeout"
 
 external enable_load_extension :
-  db -> bool -> bool = "caml_sqlite3_enable_load_extension" "noalloc"
+  db -> bool -> bool = "caml_sqlite3_enable_load_extension"
 
 let row_data stmt = Array.init (data_count stmt) (column stmt)
 let row_names stmt = Array.init (data_count stmt) (column_name stmt)

lib/sqlite3.mli

@@ -192,7 +192,7 @@ external db_close : db -> bool = "caml_sqlite3_close"
 *)
 
 external enable_load_extension :
-  db -> bool -> bool = "caml_sqlite3_enable_load_extension" "noalloc"
+  db -> bool -> bool = "caml_sqlite3_enable_load_extension"
 (** [enable_load_extension db onoff] enable/disable the sqlite3 load
     extension.  @return [false] if the operation fails, [true]
     otherwise. *)