You should really redirect before you start page output
  • line 1336 of /lib/outputrenderers.php: call to debugging()
  • line 3074 of /lib/weblib.php: call to core_renderer->redirect_message()
  • line 360 of /lib/setuplib.php: call to redirect()
  • line ? of unknownfile: call to default_exception_handler()

出力エラーが発生したため自動リダイレクトを無効にします。