Apple is switching the processor architecture of it’s Macs. Again (I transitioned PerfectTablePlan from PowerPC to Intel some hears ago). This time to their own M1 ARM chips. Reports so far have been very positive about speed and battery life of the new processors. Obviously most current Mac software has been written for Intel Macs, so they are using the Rosetta2 emulation layer to run apps compiled for Intel Macs on the ARM chips. I’m not sure how much of a performance hit this causes, but clearly it would be better to run native ARM binaries on an ARM machine. Also Apple, being Apple, want to move everyone to ARM as quickly as possible. Tough luck if you just spent big bucks on a shiny new Intel Mac.

One of my customers emailed me that the latest version of my Hyper Plan visual planner, built with Qt 5.13.1, didn’t run on an new M1 Mac. I don’t currently have an M1 Mac to test it on. But my Easy Data Transform software , built with Qt 5.15.2, apparently works fine on an M1 Mac. So I recompiled Hyper Plan using Qt 5.15.2, and was told it now works. I have found a couple of minor differences in behaviour between Qt 5.13.1 and 5.15.2, but they are too obscure to go into here. Some Qt apps may still have issues on ARM.

Currently Qt is only available as Intel binaries. Efforts are in progress to be able to build Qt as M1 (ARM) binaries. When that is complete it should be possible to ship Qt applications as a ‘fat binary’ with both Intel and ARM executables, as I did with the PowerPC to Intel transition. I’m not sure if this is going to be supported on Qt 5 and 6 or just Qt 6.

** Update Dec-2021 **

Qt 6.2 supports building M1 ARM and Intel binaries. There is no official support for M1 Arm binaries for Qt 5.

** Update Apr-2022 **

Evan of ModernCSV alterted me to an article on deploying a ‘fat binary’ from Qt 5.