We’re running a hybrid Flutter/native iOS app. Since a release we did at the start of October we’ve started getting a growing number of these crashes, seemingly only affecting iOS 12 devices, and almost always around 50 seconds after the app launches:
Crashed: PHTFlatFilePhenotype
0 <App name> 0x104d6ac MLKITx_BuildData::BaselineChangelistAsInt() + 71964
1 <App name> 0x1012078 __82-[MLKITx_PHTFlatFilePhenotype registerPackage:version:logSources:params:callback:]_block_invoke.192 + 4329873528
2 libdispatch.dylib 0x5fa38 _dispatch_call_block_and_release + 24
3 libdispatch.dylib 0x607d4 _dispatch_client_callout + 16
4 libdispatch.dylib 0x9324 _dispatch_lane_serial_drain$VARIANT$mp + 592
5 libdispatch.dylib 0x9e40 _dispatch_lane_invoke$VARIANT$mp + 428
6 libdispatch.dylib 0x124ac _dispatch_workloop_worker_thread + 596
7 libsystem_pthread.dylib 0xc114 _pthread_wqthread + 304
8 libsystem_pthread.dylib 0xecd4 start_wqthread + 4
The first release that these started happening in was using Flutter 3.10.0, and a more recent update that still has the problem is on the more recent Flutter 3.13.9.
Because it seems to be coming from within iOS itself (MLKit? Machine Learning kit? – we don’t consciously use this at all in our app) it’s hard to know where to look for a cause… iOS 12 is the latest version that various devices are able to update to, so just telling the user to update iOS isn’t an option. But presumably it is related to something we’ve changed in our code, because it started so suddenly after our app update – I just can’t see any obvious causes by looking at the diffs.
Has anybody else experienced this, and if so, did you manage to find the cause?
Our app does use Firebase as well.