Memory leak in PreferenceFragmentCompat adapter handling [121006469]

Fixed

Bug

Status Update

No update yet.

Description

js...@gmail.com

created issue #1

Dec 14, 2018 07:54PM

RecyclerView registers an observer (

https://android.googlesource.com/platform/frameworks/support/+/androidx-master-dev/recyclerview/recyclerview/src/main/java/androidx/recyclerview/widget/RecyclerView.java#1201) that is only unregistered manually, by either setting the adapter again, or calling unregisterAdapterDataObserver externally.

PreferenceFragmentCompat sets this adapter (PreferenceGroupAdapter), which implicitly registers an observer. PreferenceFragmentCompat never sets the adapter to null when the view is destroyed, so the observer keeps references to the RecyclerView and doesn't get gc'ed.

I've worked around this by explicitly setting the adapter to null in an override of onDestroyView, but since my component doesn't explicitly have ownership of the list handling, I'd argue that PreferenceFragmentCompat should do this cleanup.

It would be solved by setting the RecyclerView adapter to null in the fragment's onDestroyView.

Here's a memory dump.

2018-12-14_10-38-54_921.hprof

23 MB

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Comments

lp...@google.com <lp...@google.com> #2Jan 10, 2019 11:35PM

A couple of questions:

1. Have you saw crash in real device or only in simulators?
2. Do you use dynamic feature for language ID?

lp...@google.com <lp...@google.com> #3Jan 14, 2019 08:41PM

Marked as fixed.

Tested on Android 12 Emulator with custom executor, but cannot repro this issue.

ma...@gmail.com <ma...@gmail.com> #4Feb 28, 2020 01:26PM

Second crash in the description is from a real device. Experienced it myself on two different Xiaomi phones, plus lots of crashes from users in the Google Play console.
Dynamic features are not used in the application.

As a wild guess, I have downgraded build tools from 31.0.0 to 30.0.3, compileSdk from 31 to 30, and moved all work with Language ID to the service in a separate process (just to be sure that crash can kill secondary process instead of main). This combination is in beta for 2 days by now and I don't see any SIGSEGV crashes.

jb...@google.com <jb...@google.com> #5Feb 28, 2020 05:57PM

Hmm, I feel the crash might be something related to separate/secondary process.

I also changed compileSdk and targetSDK to 31 but still cannot repro this issue.

ma...@gmail.com <ma...@gmail.com> #6Feb 29, 2020 09:16PM

On the contrary, there was no separate process before, when crashes started.

In the new build (with the aforementioned changes) I can see SIGSEGV crash, but only one instead of dozens and it has a bit different backtrace:

signal 11 (SIGSEGV), code 1 (SEGV_MAPERR)
liblanguage_id_jni.so (offset 0x11e000)

backtrace:
  #00  pc 000000000003c7c0  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 000000000003b960  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 000000000003bb48  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 000000000003bafc  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 0000000000036c98  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 0000000000032714  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 0000000000031cac  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 0000000000057438  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/oat/arm64/base.odex (offset 0x57000)

Issue 121006469