Comment 114 for bug 1522422

There are plans to get Drupal 7 working with PHP 7, but there are still some issues remaining. With everything that's going on with Drupal 8, I don't think folks have had a chance to jump into this too deeply just yet. For more information, see https://www.drupal.org/node/2454439.

I wouldn't focus too much on the Debian packages. In my experience, they're not used very widely (as stated above) as there are usually custom changes. So getting Drupal 7 running on PHP 7 (without the Debian packages) would be the goal here. The packages aren't even mentioned in the official installation guide, https://www.drupal.org/documentation/install/download, or on the OS-specific page: https://www.drupal.org/node/557908.

Having said that, though, I'd be curious to know if the package maintainers had any insight they could share.