A strange crash about FontAssetDownloadManager

Which iOS version are you running?

I started seeing a large number of these crashes starting on June 8. Same backtrace.

So far seeing only on iOS 14.4.2.

I'm seeing the same crash in iOS 14.4.2, 14.4, and 14.3 in an iPad app. First started seeing them on June 8.

NSInvalidArgumentException: -[__NSCFNumber compare:]: nil argument

0  CoreFoundation          ___exceptionPreprocess
1  libobjc.A.dylib         _objc_exception_throw
2  CoreFoundation          __CFThrowFormattedException
3  CoreFoundation          -[__NSCFNumber compare:].cold.1
4  CoreFoundation          -[__NSCFNumber compare:]
5  CoreFoundation          -[__NSCFNumber isEqualToNumber:]
6  CoreText                +[FontAssetDownloadManager filterIncompatibleAsset:]
7  CoreText                +[FontAssetDownloadManager availableMobileAssetsWithOptions:error:]
8  CoreText                +[FontAssetDownloadManager availableMobileAssetsWithOptions:manager:error:]
9  CoreText                -[FontAssetDownloadManager mobileAssetsForUnmatched:]
10 CoreText                -[FontAssetDownloadManager downloadFontAssets]
11 CoreText                ___CTFontDescriptorMatchFontDescriptorsWithProgressHandler_block_invoke
12 libdispatch.dylib       __dispatch_call_block_and_release
13 libdispatch.dylib       __dispatch_client_callout
14 libdispatch.dylib       __dispatch_lane_serial_drain$VARIANT$mp
15 libdispatch.dylib       __dispatch_lane_invoke$VARIANT$mp
16 libdispatch.dylib       __dispatch_workloop_worker_thread
17 libsystem_pthread.dylib __pthread_wqthread
18 libsystem_pthread.dylib _start_wqthread

I'm also seeing this under similar circumstances, since around June 8. I'm also seeing reports from as far back as iOS 14.0.

Please post the fully symbolicated Apple crash report using the attachment feature.

To clarify my comment, I'm looking for the entire crash report, not just a portion of it. We always want to see the full crash reports.

I have added steps to reproduce and a detailed explanation of the crash to FB9147434.

At this time, the fix seems to be to update to iOS 14.5 or above.

I have added steps to reproduce and a detailed explanation of the crash to FB9147434.

I took a look at your bug report and you’ve only attached third-party crash reports. Unfortunately that really limits our ability to help. Do you have any Apple crash reports for this problem?

At this time, the fix seems to be to update to iOS 14.5 or above.

OK, well that’s good news anyway.

Other folks on this thread:

• Are you seeing this on 14.5 or later?

• If so, please post an Apple crash report. Use the text attachment feature (click the paperclip icon and then choose Add File) to avoid clogging up the timeline.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

I'm not seeing any crashes beyond iOS 14.5 in the Xcode organizer. I can provide any older iOS 14 crashes from Xcode if that's useful.

Hi eskimo, attached a screenshot as well as stack trace. Please help fix this issue ASAP as all our users under 14.5 are experiencing this since 6/8.

Also a screenshot from Xcode crash report, which confirmed the affected systems from 14.0-14.4

We're also seeing this. It popped up on our radar on June 7 and quickly became our top crash, both in our application and in applications that use our framework. The crash occurred outside of our release cycle and affects iOS 14 versions before 14.5.

https://twitter.com/steipete/status/1402874404187615232?s=21

I just filed FB9158935 with details and crash reports attached. I hope that helps.

fayedua wrote:

attached a screenshot as well as stack trace.

Thanks but, alas, it doesn’t help. To make progress with issues like this I need an Apple crash report.

MatejB wrote:

I just filed FB9158935 with details and crash reports attached.

Thanks!

Based on the crash reports attached to that bug I believe that this is a known issue in Core Text that was fixed in iOS 14.5 (r. 74664417).

That gels with this:

The crash occurred outside of our release cycle and affects iOS 14 versions before 14.5.

and various comments from tjlihao, wooster, and dbxzsw.

So, in summary:

• If you have users seeing this on earlier systems, suggest that they update to the latest OS.

• If you see this occur on 14.5 or later, that’s a new issue and definitely bugworthy.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

I've reached out to our WWDC contact to see if there's any possibility to revert this server-side change to the list from before June 7. We're calling font loading code on initialize so this issue results in a crash-on-launch for products using our SDK that have been using the downloadable fonts feature in the past.

To repeat: This is a regression Apple introduced server-side onto existing, working code. This should be reverted.

This is definitely a bug caused by Apple updating the server during WWDC. Any app that supports downloadable font installation will cause a lot of bugs. I request that this update be rolled back immediately.