Hmm if there is something like that, I've never seen it. I think things between /* */ are just comments, and there's not usually a distinction between comments and comments-within-comments.
In general I would recommend to
1) Make sure your code is in VCS like git. 2) Delete instead of comment out code that isn't used, unless you're sure it's temporary.
Because commented-out code keeps piling on and really doesn't help readability of your code.
If you change your mind you can get it back from the history.