[Crashlytics] Native stack not symbolicated for armeabi-v7a builds on 64-bit devices running in compatibility mode

[IosephKnecht]

Describe your environment

• Firebase Component: Crashlytics
• SDK Version: com.google.firebase:firebase-crashlytics-ndk:19.2.1
• Gradle Plugin Version: com.google.firebase:firebase-crashlytics-gradle:2.9.9
• Firebase CLI Version (for manual upload): 15.21.0
• Android Gradle Plugin (AGP): 8.10.1
• NDK Version: 29.0.14206865
• Device: Samsung SM-S911B (Android 16)

Describe the problem

Native crash stacks are not symbolicated in the Firebase Crashlytics console for armeabi-v7a (32-bit) builds when running on a 64-bit device in compatibility mode. The same build works correctly on a native 64-bit (arm64-v8a) APK on the same device.

Steps to reproduce:

1. Build an APK containing native libraries only for the armeabi-v7a ABI.
2. Install and run the APK on a 64-bit ARM device (e.g., Samsung SM-S911B).
3. Trigger a native crash (e.g., via SIGABRT or a deliberate null pointer dereference).
4. Observe the crash report in the Firebase Crashlytics console.

Expected result:
The crash report is successfully received, and the native stack trace is fully symbolicated (showing function names and line numbers).

Actual result:
The crash report is successfully received, but the native stack trace is not symbolicated. Only memory addresses or raw function offsets are shown.

Additional investigation and findings

1. The symbols themselves are delivered.

   • Repeated manual uploading of symbols using the Firebase CLI (firebase crashlytics:symbols:upload) did not resolve the issue, ruling out a CI/upload problem.

2. The minidump is valid and can be symbolicated locally.

   • A raw minidump file (from the device path .../native/pending) from a crash on the armeabi-v7a build was extracted and processed locally using minidump_stackwalk with the corresponding symbol files.
   • The local symbolication was successful, producing a fully readable stack trace.

3. The issue is specific to armeabi-v7a on a 64-bit host.

   • The same device (SM-S911B) running the arm64-v8a version of the same APK produces a symbolicated stack trace in the Crashlytics console without any issues.
     arm-v7a stacktrace from Crashlytics
     arm64-v8a stacktrace from Crashlytics

Key Question

The local symbolication test confirms that the minidump and symbols are valid. The problem therefore appears to be specific to the backend processing of minidumps generated from a 32-bit (armeabi-v7a) process running on a 64-bit device. Is this a known limitation or bug?

Suggested hypothesis

The local symbolication test confirms that the minidump and symbols are valid. The problem therefore appears to be specific to the backend processing of minidumps generated from a 32-bit (armeabi-v7a) process running on a 64-bit device.

While the issue is unlikely to be related to 16KB page alignment (as this is not a strict requirement for armeabi-v7a), it may be caused by differences in how the 32-bit unwind data is interpreted by the backend, or a bug in the backend's minidump processing for this specific scenario.

P.S

We are considering updating the Firebase Gradle plugin to 3.x.x and the Firebase BoM to 34.x.x, but would appreciate guidance before doing so.

[lehcar09]

Hi @IosephKnecht, thank you for raising this issue. I tried replicating this scenario, however, I wasn't able to get a hold of a 64-bit device.

Could you try reproducing the issue using the latest Firebase Crashlytics Gradle plugin and see if the issue persists? You can check this FAQ section on how to migrate to Crashlytics Gradle plugin v3.

We usually recomment to ensure that you're using the latest Firebase Crashlytics Gradle plugin to ensure that you have the latest bug fixes and improvements. In addition to that, the Crashlytics Gradle plugin (v3.0.0) includes breaking changes
and improvements on support for native apps and customized builds. This release also includes the changes listed in this release note.

[IosephKnecht]

Hi @lehcar09, returning with feedback. What I did:

• Updated crashlytics gradle plugin from 2.9.9 to 3.0.7
• Updated google services plugin plugin from 4.3.14 to 4.5.0
• Updated com.google.firebase:firebase-crashlytics-ndk from 19.2.1 to 20.0.6 (by updating the BOM to 34.15.0)

And reproduced the issue on the same device (SM-S911B). Unfortunately, a stack was still not symbolicated.
Perhaps I missed something during the update?

[lehcar09]

Thank you for checking the issue in the latest SDK version. Let me consult this to our engineers and get back to you. Thanks!