Android debug symbols not symbolicated when using Flutter flavors with --split-debug-info

[Kobby-Bawuah]

Environment

sentry_dart_plugin: 3.2.1 (latest)
sentry_flutter: 9.10.0 / 9.11.0
Flutter: 3.38.9 (stable)
Platform: Android (arm64)
Build type: appbundle with flavors

Steps to Reproduce

• Have a Flutter project with multiple Android flavors (e.g. googlePlay, appGallery)
• Build with flavors and --split-debug-info:
  flutter build appbundle --flavor=googlePlay --obfuscate --split-debug-info=debug_info/googlePlay --extra-gen-snapshot-options=--save-obfuscation-map=build/obfuscation.map.json
• Configure pubspec.yaml:
  sentry: symbols_path: debug_info upload_source_maps: true upload_sources: true dart_symbol_map_path: build/obfuscation.map.json
• Run dart run sentry_dart_plugin
• Trigger an error on Android and view the issue in Sentry

Expected Result

Android stack traces are symbolicated, with function names, file names, and line numbers visible — the same as iOS.

Actual Result

All Android stack frames show symbolicator_status: "missing_symbol". iOS events from the same project are symbolicated correctly.

Root cause: Debug ID mismatch between uploaded .symbols file and the libapp.so in the final APK.

The upload logs show the plugin uploads symbols from the wrong flavor:
UPLOADED edda1b4f-6d6f-b66d-128a-5ff367eac22c (merged_native_libs/googlePlayRelease/.../libapp.so; arm64 library)UPLOADED edda1b4f-6d6f-b66d-128a-5ff3d45a56ef (flutter/appGalleryRelease/arm64-v8a/app.so; arm64 library)

The debug companion (with DWARF info) is uploaded with the appGallery debug ID:
UPLOADED edda1b4f-6d6f-b66d-128a-5ff3d45a56ef (app.android-arm64.symbols; arm64 debug companion)

But the running app reports the googlePlay debug ID:
debug_id: "edda1b4f-6d6f-b66d-128a-5ff367eac22c"

In Sentry's Debug Files, searching for the event's debug ID shows only the stripped libapp.so (symtab + unwind, no debug). The debug companion with full DWARF info is associated with a different debug ID.

Key observations:

• Removing --flavor from the build command results in correct symbolication
• Cleaning the build environment (including debug_info/ and .dart_tool/) before building does not fix the issue
• The .dart_tool/flutter_build/ directory generates separate subdirectories for each flavor, and the plugin/CLI picks up artifacts from the wrong one
• iOS is unaffected because dSYM generation doesn't have this flavor interaction

DARTPL-25 — "Missing debug symbols since updating to Flutter 3.32.8" (closed as not planned, same root cause)

[linear]

DARTPL-39

[Kobby-Bawuah]

ZD Ticket for more context: https://sentry.zendesk.com/agent/tickets/174070

[buenaflor]

I believe this issue has been introduced in 3.2.0.

I am investigating adding a flavor config

[buenaflor]

Is it possible to verify if this issue happens in 3.1.1 as well

[Maatteogekko]

Yes, still happens on 3.1.1. The issue id on our sentry dashboard is 7287857904.

These are the logs of the plugin:

[❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚] 0% reading config values..        
Searching for pubspec.yaml or sentry.properties config...

Found config from pubspec.yaml

Downloading Sentry CLI 2.41.1 from https://downloads.sentry-cdn.com/sentry-cli/2.41.1/sentry-cli-Darwin-universal to .dart_tool/pub/bin/sentry_dart_plugin/sentry-cli

Sentry CLI binary checksum verification passed successfully (hash: 4b6703bb6160accb7d3552128945357910ff273fde5d5a8aa4d1668958bb9472).

Sentry CLI downloaded successfully.
☑ reading config values                                                             
☑ validating config values                                                             
[❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚] 18% uploading debug symbols..                                
> Found 0 debug information files
> No debug information files found

> Found 146 debug information files (1 with embedded sources)

> Resolved source code for 4 debug information files

> Prepared debug information files for upload

> Uploaded 8 missing debug information files

> File upload complete:

  UPLOADED 3dede911-8a22-7e86-4ea9-e7ff1b341a00 (stripped_native_libs/googlePlayRelease/stripGooglePlayReleaseDebugSymbols/out/lib/armeabi-v7a/libapp.so; arm library)
  UPLOADED 00ce8f83-2087-944d-cc74-84da0b5fee03 (flutter/appGalleryRelease/x86_64/app.so; x86_64 library)
  UPLOADED 00ce8f83-2087-944d-cc74-84da126b5c81 (stripped_native_libs/googlePlayRelease/stripGooglePlayReleaseDebugSymbols/out/lib/x86_64/libapp.so; x86_64 library)
  UPLOADED 3dede911-8a22-7e86-4ea9-e7ff1b341a00 (merged_native_libs/googlePlayRelease/mergeGooglePlayReleaseNativeLibs/out/lib/armeabi-v7a/libapp.so; arm library)
  UPLOADED 00ce8f83-2087-944d-cc74-84da126b5c81 (merged_native_libs/googlePlayRelease/mergeGooglePlayReleaseNativeLibs/out/lib/x86_64/libapp.so; x86_64 library)
  UPLOADED 3dede911-8a22-7e86-4ea9-e7ffa26bc1dc (flutter/appGalleryRelease/armeabi-v7a/app.so; arm library)
  UPLOADED edda1b4f-8628-a867-128a-5ff3a435a626 (flutter/appGalleryRelease/arm64-v8a/app.so; arm64 library)
  UPLOADED edda1b4f-8628-a867-128a-5ff360b23c6d (stripped_native_libs/googlePlayRelease/stripGooglePlayReleaseDebugSymbols/out/lib/arm64-v8a/libapp.so; arm64 library)

> Found 1 debug information file

> Resolved source code for 1 debug information file

> Prepared debug information files for upload

> Uploaded 2 missing debug information files

> File upload complete:

  UPLOADED 00ce8f83-2087-944d-cc74-84da0b5fee03 (app.android-x64.symbols; x86_64 debug companion)
  UPLOADED 00ce8f83-2087-944d-cc74-84da0b5fee03 (app.android-x64.symbols; x86_64 sources)

> Found 1 debug information file

> Resolved source code for 1 debug information file

> Prepared debug information files for upload

> Uploaded 2 missing debug information files

> File upload complete:

  UPLOADED edda1b4f-8628-a867-128a-5ff3a435a626 (app.android-arm64.symbols; arm64 sources)
  UPLOADED edda1b4f-8628-a867-128a-5ff3a435a626 (app.android-arm64.symbols; arm64 debug companion)

> Found 1 debug information file

> Resolved source code for 1 debug information file

> Prepared debug information files for upload

> Uploaded 2 missing debug information files

> File upload complete:

  UPLOADED 3dede911-8a22-7e86-4ea9-e7ffa26bc1dc (app.android-arm.symbols; arm sources)
  UPLOADED 3dede911-8a22-7e86-4ea9-e7ffa26bc1dc (app.android-arm.symbols; arm debug companion)
☑ uploading debug symbols                                                             

Created release [redacted]@8.4.1+348
[❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚❚] 27% uploading source maps..                               
Web build directory "build/web" does not exist, skipping JS file enumeration.

Skipping source maps upload. Could not inject debug ids.
☑ uploading source maps                                                             

+---------------+--------------+
| Repository    | Revision     |
+---------------+--------------+
| [redacted] / App | b3766d018b3f |
+---------------+--------------+

Finalized release [redacted]@8.4.1+348

[denrase]

When multiple flavors share the same --split-debug-info directory, the second flutter build overwrites the first flavor's .symbols files. By the time the plugin runs, only the last-built flavor's debug companions exist — the other flavor gets missing_symbol. Checked with on Flutter 3.38.9.

This is not happening when using flavor-specific --split-debug-info paths:

 # ❌ Shared path — second build overwrites first flavor's .symbols
 flutter build appbundle --flavor=googlePlay --obfuscate --split-debug-info=debug_info
 flutter build appbundle --flavor=appGallery --obfuscate --split-debug-info=debug_info

 # ✅ Separate paths — each flavor's .symbols are preserved
 flutter build appbundle --flavor=googlePlay --obfuscate --split-debug-info=debug_info/googlePlay
 flutter build appbundle --flavor=appGallery --obfuscate --split-debug-info=debug_info/appGallery

With symbols_path: debug_info in your pubspec, the plugin should recursively find and upload .symbols from both subdirectories.

We verified this on a real Sentry project — shared path produces missing_symbol for the first-built flavor, while separate paths result in full symbolication for both. For this we threw two errors with unique separate message per flavor.

@Kobby-Bawuah From the initial message of you I'm assuming that you have separate split-debug-info and the symbols_path with the parent directory, so this setup should work.

[denrase]

Could you help us narrow down what's different in your setup? If you're still facing this, it would help to see:

1. The full build script with both flavor commands in order
2. After both builds, the output of find debug_info -type f -name "*.symbols" and file on each — this shows the debug IDs embedded in the files
3. The full plugin output with SENTRY_LOG_LEVEL=debug dart run sentry_dart_plugin
4. The debug_id from a failing event in Sentry (visible in the event's debug meta)

Comparing 2 and 4 would tell us whether the .symbols have the wrong debug ID or whether the mismatch happens elsewhere.

[Maatteogekko]

Hello, this still reproduces for me. These are the requested info.

1. flutter build appbundle --obfuscate --split-debug-info=debug_info/googlePlay --extra-gen-snapshot-options=--save-obfuscation-map=build/obfuscation.map.json --flavor=googlePlay Note that I don't need to build the second flavor for this to reproduce. I cleaned my workspace of all flutter things, then ran the command above, followed by the sentry plugin.
2. find debug_info -type f -name "*.symbols" with file info

debug_info/googlePlay/app.android-x64.symbols -  ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, BuildID[md5/uuid]=098f22967ac8d45821ce97ce52f93830, with debug_info, not stripped
debug_info/googlePlay/app.android-arm64.symbols - ELF 64-bit LSB shared object, ARM aarch64, version 1 (SYSV), dynamically linked, BuildID[md5/uuid]=7a3ef93056d347233fa36f07aea82bcc, with debug_info, not stripped
debug_info/googlePlay/app.android-arm.symbols - ELF 32-bit LSB shared object, ARM, EABI5 version 1 (SYSV), dynamically linked, BuildID[md5/uuid]=b42ed7fe1a1e770714e0b836e57038fc, with debug_info, not stripped

3. See attachment (plugin version is 3.2.1)
4. This is the debug_id of the image loaded by sentry for this issue: 30f93e7a-d356-2347-3fa3-6f07d5b6d4c4. (issue id: 7341068855)

---

My sentry plugin config:

sentry:
  symbols_path: debug_info
  upload_source_maps: true
  upload_sources: true
  dart_symbol_map_path: build/obfuscation.map.json

sentry_symbols_upload.log

[DmitrijBuckovsky]

Hi, I had the same problem and spent the whole day trying to figure out what the problem was. Thanks to AI GPT-5.4 max, we found this solution. Try it out if it helps you. Honestly, I don't understand the problem too well, so I'm attaching the generated answer from AI here:

---

The app uses multiple Android product flavors (for example production and development). We were intentionally building only a single flavor (production) with --obfuscate and --split-debug-info, and the Sentry upload itself was working, but the uploaded symbols did not match the runtime binary that was actually installed.

What was happening:

• The project had multiple Android release flavors.
• Even though we were invoking only a production release build, Flutter/Gradle did not stay isolated to only the selected release flavor during symbol generation.
• Because the split-debug-info output path was shared, the generated app.android-arm64.symbols file could end up being produced from another release flavor.
• In our case, we were building production, but the generated symbols matched the other flavor’s release output instead of the runtime binary we actually shipped.
• Sentry then received valid debug files, but they did not match the runtime app.so Build ID / Debug ID, so Dart stack traces stayed unsymbolicated (no Dart file names, line numbers, or source context).

In short: we were only asking Flutter to build one flavor, but the release symbol generation was not properly isolated to that flavor, and the shared symbol output could be overwritten by another release flavor.

The fix was to explicitly keep only the requested release flavor in the build graph.

Example Gradle fix:

android {
    flavorDimensions += "default"

    productFlavors {
        create("production") {
            dimension = "default"
        }
        create("development") {
            dimension = "default"
        }
    }

    variantFilter {
        val activeFlavor = project.findProperty("active-flavor")?.toString()?.lowercase()
            ?: return@variantFilter
        val buildTypeName = buildType?.name ?: return@variantFilter
        val variantFlavors = flavors.map { it.name.lowercase() }

        if (buildTypeName == "release" &&
            variantFlavors.isNotEmpty() &&
            activeFlavor !in variantFlavors
        ) {
            ignore = true
        }
    }
}

Then build with the selected flavor explicitly:

flutter build appbundle \
  --flavor production \
  -Pactive-flavor=production \
  -t lib/main_production.dart \
  --obfuscate \
  --split-debug-info=build/app/outputs/symbols \
  --extra-gen-snapshot-options=--save-obfuscation-map=build/app/obfuscation.map.json

And upload with:

dart run sentry_dart_plugin

After that, the generated Flutter symbols matched the actual runtime binary, and Sentry started showing proper Dart file names, line numbers, and source context.

A useful local verification before uploading anything is to compare the Build ID of the runtime app.so and the generated .symbols file:

file build/app/intermediates/flutter/productionRelease/arm64-v8a/app.so
file build/app/outputs/symbols/app.android-arm64.symbols

The BuildID[md5/uuid] values must match.

[denrase]

Thank you @Maatteogekko & @DmitrijBuckovsky, i'll look into this and report back.

[denrase]

You are correct @DmitrijBuckovsky, this is indeed the solution here. I verified this locally, and it works as a workaround.

The issue is that a release build for one flavor can still compile another release flavor, which can overwrite the selected flavor’s --split-debug-info output. This seems to be a flutter behaviour we cannot change. The result is .symbols files that don’t match the final app binary. Thank you @Maatteogekko, I could reproduce this with the info you provided. 🙇

A minimal workaround is to ignore non-selected release variants in Gradle and pass the active flavor from the build command.

In android/app/build.gradle.kts:

  android {
      variantFilter {
          if (buildType?.name != "release") return@variantFilter

          val activeFlavor = (project.findProperty("active-flavor") as String?)
              ?.lowercase()
              ?: return@variantFilter

          val variantFlavors = flavors.map { flavor -> flavor.name.lowercase() }
          if (activeFlavor !in variantFlavors) {
              ignore = true
          }
       }
   }

Then build with matching values for --flavor and also pass the active-flavor:

flutter build appbundle \
  --flavor=googlePlay \
  --target=lib/main_googlePlay.dart \
  --obfuscate \
  --split-debug-info=debug_info/googlePlay \
  --android-project-arg=active-flavor=googlePlay

Confirmed that with this in place:

• only the selected release flavor is compiled
• the generated app.android-*.symbols match the final AAB

Thank you @DmitrijBuckovsky, we will add this to the readme. I'll also check if we can filter out symbols with incorrect debug ids, so we don't upload them and also notify users when the plugin runs.