Starting April 12, users running the current version of macOS High Sierra were greeted with a warning the first time they launched any non-Apple app that wasn’t 64-bit. See above for what it looks like in CrossOver.
Apple has been migrating its software along with its hardware from 32 to 64-bit over the past few years. There are several reasons why transitioning to 64-bit only is inevitable and advantageous: 64-bit apps have access to more memory and allow for much more efficient performance. As Apple introduces new OS-level technologies, they are written for and require 64-bit only apps. When you have the ability to run both 64 and 32-bit apps, all of the libraries, frameworks, and parts of the operating system that the applications rely on also have to come in 64 and 32-bit variants. Even if there is only one 32 bit application installed, the system needs to bring in 32 bit variations of all the other 64 bit libraries. Modern operating systems employ dynamic linking, so multiple applications that use the same library only load it into memory once. As soon as the user launches a 32-bit app, now there are two copies of those libraries in memory. Once the transition is complete, users will all see the benefit that comes from ditching the 32-bit libraries necessary to run the old applications across the entire operating system, resulting in faster load times and improved battery life.
The transition away from 32-bit apps has already begun, and at some point in the future those apps will not be able to run at all on current macOS releases. So far, Apple has not made any specific announcements about when that may happen (though we are nearing this year’s developer conference, where we may get more information).
At Apple’s Worldwide Developer Conference last year, the transition to a 64-bit only operating system was announced, stating that macOS High Sierra would be the last version of macOS to run 32-bit applications “without compromise”. For now, the one-time warning when a 32-bit app is launched is just that — a warning. The performance goes unchanged, and the alert only appears the one time.
This week we are releasing CrossOver 17.5, the first step towards full 64-bit compatibility. To accomplish this, we’ve removed the Legacy X Window System. This has been included in CrossOver only as a fallback for a few years now, and will affect a very small number of applications. If you are using CrossOver to run an application that relies on the Legacy X Window System, please contact our Support Team so we can work to find a solution for you.
CrossOver 17.5 also contains several bug fixes targeted at Office 2016. Microsoft Word, Excel, and Powerpoint should install more easily and see fewer crashes and freezes.
This is only the first step in the process of aligning with the new 64-bit only conventions going forward. If you have any problems with a change as it’s implemented, or if you have any questions about the process in general please let us know through our support system. This is going to be an exciting year with some big changes on the back-end, and it is our goal to make this transition as smooth as possible for our users.
Brian joined CodeWeavers in 2017 after working undercover at Apple for seven years. He currently holds a degree in satire but doesn’t like to brag about it. He is a member of the CodeWeavers Support team, so if you have a problem getting your application to run, there’s a good chance you’ll be hearing from him.