While Nintendo hasn't issued a patch to fix Pokemon X/Y's Lumiose save bug, they have put out a helpful image. According to Nintendo, you shouldn't save your game when standing in the blue areas.

Nintendo issued a press release about the Lumiose City bug. Areas in blue are places where you should NOT save. pic.twitter.com/IEwzHceaIo

— Tamashii Hiroka (@TamashiiHiroka) October 18, 2013