Xcode console output is full of CoreUI warnings about image subtype mismatches when running on Mac Catalyst

CoreUI is sending warning messages to the Xcode console when creating a UIImage from an image file with Mac idiom from the asset catalog, while running on Catalyst.

  • My target is set to support running on Mac Catalyst with Optimize for Mac enabled (the latter seems to be the most important part).
  • Loading the image into a UIImage with the designated initializer and presenting it in a UIImageView produces the following console messages:
2023-02-15 10:53:18.014394+0100 CatalystImageConsoleMessage[64253:8834791] [framework] CoreUI: _Bool CUIValidateIdiomSubtypes(NSInteger, NSUInteger *) got a device subtype '32401' that it match with idiom '7':mac. Assuming subtype should be 0 instead.
2023-02-15 10:53:18.014446+0100 CatalystImageConsoleMessage[64253:8834791] [framework] CoreUI: _Bool CUIValidateIdiomSubtypes(NSInteger, NSUInteger *) got a device subtype '32401' that it match with idiom '7':mac. Assuming subtype should be 0 instead.
2023-02-15 10:53:18.014503+0100 CatalystImageConsoleMessage[64253:8834791] [framework] CoreUI: _Bool CUIValidateIdiomSubtypes(NSInteger, NSUInteger *) got a device subtype '32401' that it match with idiom '7':mac. Assuming subtype should be 0 instead.
2023-02-15 10:53:18.014533+0100 CatalystImageConsoleMessage[64253:8834791] [framework] CoreUI: _Bool CUIValidateIdiomSubtypes(NSInteger, NSUInteger *) got a device subtype '32401' that it match with idiom '7':mac. Assuming subtype should be 0 instead.

Working with more than a handful of images from the catalog makes the Xcode console output borderline unreadable because of these messages. The console doesn't have an option to filter out messages (and in general we consider it bad practice to ignore messages on the console).

Tested on Xcode 14.2 with macOS 13.2.

You can find a sample project at https://github.com/tamasjager/CatalystImageConsoleMessage.

Thank you! I filed a feedback report with Apple about this issue and received several replies, however, the cause of the issue and was unclear to us. I have added your findings and repo link to the official Apple feedback report. Your findings are invaluable.

Hi! Any news on this? It makes debugging in Xcode painfully slow and the console is pretty much useless (Xcode 14.2, macOS 13.3.1).

Hi. I have the same message with Catalyst optimised for macOS when showing a VStack of an Image and a Text in a LazyVGrid.

Still present in Xcode 15.0 (15A240d). At least with the new debug console the messages of the "com.apple.coreui" subsystem can be filtered out.

Xcode console output is full of CoreUI warnings about image subtype mismatches when running on Mac Catalyst
 
 
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