PA-Required to go to work for meeting on day(s) off, canceled no notice, no compensation or pay (hourly employee). Is it legal?

Had a scheduled meeting I was required to go to at work on what was supposed to be a day off. I verified the time and place the day before with the boss. When I show up at said time, I'm told it's been canceled. My commute isn't horribly long, but some have to drive an hour or so. Now I'm aware they would be required to pay us had the meeting taken place while we were there, but can they require you to come in any time, make you drive in for nothing with no compensation?