Styjun

I was using Mobile Vision API to detect barcodes using a camera stream, just like in this example: https://github.com/googlesamples/android-vision/tree/master/visionSamples/barcode-reader, unfortunately there is an issue in which the app crash out of the blue due to a null pointer dereference in the barcode reader's native code, see issue #351.

Although the reported issue is on a Pixel device I found the same stacktrace on my Samsung Tab A devices running from Android 7 and 8, here is the stacktrace of the error

 Build fingerprint: 'samsung/gta2xlltespr/gta2xlltespr:8.1.0/M1AJQ/T597PVPU1ASA2:user/release-keys'
03-13 15:42:47.077 F/DEBUG (11969): Revision: '7'
03-13 15:42:47.077 F/DEBUG (11969): ABI: 'arm'
03-13 15:42:47.078 F/DEBUG (11969): pid: 11696, tid: 11874, name: Thread-24 03-13 15:42:47.078 F/DEBUG (11969): signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 0xc
03-13 15:42:47.078 F/DEBUG (11969): Cause: null pointer dereference
03-13 15:42:47.078 F/DEBUG (11969): r0 ea09c5a8 r1 a25b973a r2 ea09b6d0 r3 00000000
03-13 15:42:47.078 F/DEBUG (11969): r4 00000000 r5 ea09b6d0 r6 c7b967f0 r7 c7b96904
03-13 15:42:47.078 F/DEBUG (11969): r8 00000022 r9 00000001 sl 43dc8000 fp 44518000
03-13 15:42:47.078 F/DEBUG (11969): ip eb2b3d58 sp c7b967e0 lr eb28a345 pc c8951c12 cpsr 200d0030
03-13 15:42:47.080 F/DEBUG (11969): 
03-13 15:42:47.080 F/DEBUG (11969): backtrace:
03-13 15:42:47.080 F/DEBUG (11969): #00 pc 00011c12 /data/data/com.google.android.gms/app_vision/barcode/libs/armeabi-v7a/libbarhopper.so
03-13 15:42:47.080 F/DEBUG (11969): #01 pc 0000a345 /data/data/com.google.android.gms/app_vision/barcode/libs/armeabi-v7a/libbarhopper.so
03-13 15:42:47.080 F/DEBUG (11969): #02 pc 0000331d /data/data/com.google.android.gms/app_vision/barcode/libs/armeabi-v7a/libbarhopper.so
03-13 15:42:47.080 F/DEBUG (11969): #03 pc 000043df /data/data/com.google.android.gms/app_vision/barcode/libs/armeabi-v7a/libbarhopper.so
03-13 15:42:47.081 F/DEBUG (11969): #04 pc 00001e63 /data/data/com.google.android.gms/app_vision/barcode/libs/armeabi-v7a/libbarhopper.so
03-13 15:42:47.081 F/DEBUG (11969): #05 pc 00002a91 /data/data/com.google.android.gms/app_vision/barcode/libs/armeabi-v7a/libbarhopper.so
03-13 15:42:47.081 F/DEBUG (11969): #06 pc 00000adf /data/user_de/0/com.google.android.gms/app_chimera/m/00000034/oat/arm/DynamiteModulesA.odex (offset 0x6000)

This is an important feature in my current app and would really appreciate if someone can tell me if it's safe to use MLKit.

SIGSEGV alias 11 means segmentation fault; memory address 0xc not mapped to object; siginfo.h defines that and this is caused by accessing an address which had not been allocated (it's almost the same as an IndexOutOfBoundsException in Java, but on the memory allocation level).

the example app uses hopelessly outdated dependencies. better try the current version:

implementation "com.google.android.gms:play-services-base:16.1.0"
implementation "com.google.android.gms:play-services-vision:17.0.2"

it's difficult to tell if this is "save", because the question does not feature the least code - nor does it tell which version of the library you use. so that's nothing one could reproduce in a reliable manner.