[Android] 16KB Page Size Compatibility Issue in React Native Core Libraries

[amanchd16]

Description

Priority: High - Affects all React Native Android apps and Google Play Store compatibility 🚨

Summary

React Native core libraries (libjsi.so, libreactnative.so, libhermes.so, libhermestooling.so, libfbjni.so, libc++_shared.so) are not compatible with Android's 16KB page size requirement on 32-bit architectures, causing Google Play Store warnings and potential crashes on devices with 16KB page sizes.

Environment

React Native version: 0.80.0 / 1
Platform: Android
NDK version: 27.1.122
Architecture affected: armeabi-v7a, x86 (32-bit architectures)
Architecture working: arm64-v8a, x86_64 (64-bit architectures)
Build tools: 35.0.0

Google Play Store now enforces 16KB page size compatibility for Android apps. Our analysis reveals that React Native's core native libraries have page alignment issues on 32-bit architectures, while 64-bit architectures work correctly.

❌ Problem architectures (aligned to 0x4 - 4KB):

armeabi-v7a/libjsi.so - JavaScript Interface
armeabi-v7a/libreactnative.so - React Native Core
armeabi-v7a/libhermes.so - Hermes JavaScript Engine
armeabi-v7a/libhermestooling.so - Hermes Tooling
armeabi-v7a/libfbjni.so - Facebook JNI
armeabi-v7a/libc++_shared.so - C++ Standard Library
x86/libjsi.so
x86/libreactnative.so
x86/libhermes.so
x86/libhermestooling.so
x86/libfbjni.so
x86/libc++_shared.so

✅ Working architectures (aligned to 0x4000 - 16KB):

arm64-v8a/libjsi.so
arm64-v8a/libreactnative.so
arm64-v8a/libhermes.so
arm64-v8a/libhermestooling.so
arm64-v8a/libfbjni.so
arm64-v8a/libc++_shared.so
x86_64/* (all corresponding libraries)

Request

This is a critical compatibility issue affecting all React Native Android applications. Please prioritize updating the build configuration to ensure all React Native core libraries support 16KB page sizes across all architectures.
Suggested timeline: This should be addressed in the next patch release due to its impact on Google Play Store compatibility.

Steps to reproduce

Reproducer: RNTesterPlayground.js is not applicable for this issue.

This is a native library build configuration issue, not a JavaScript runtime issue. The problem exists in how React Native's native libraries (.so files) are compiled and linked by the NDK build system.

To reproduce the actual issue:

1. Build any React Native Android app
2. Extract the APK: unzip app-release.apk -d extracted/
3. Analyze native libraries: objdump -x extracted/lib/armeabi-v7a/libreactnative.so | grep Align
4. Observe 4KB alignment (0x4) instead of required 16KB alignment (0x4000)

JavaScript code cannot reproduce this because it's a compilation/linking issue that affects the ELF binary format of native libraries, not runtime behavior.

React Native Version

0.80.1

Affected Platforms

Runtime - Android

Output of npx @react-native-community/cli info

System:
  OS: macOS 15.5
  CPU: (8) arm64 Apple M1
  Memory: 144.73 MB / 16.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 22.0.0
    path: ~/.nvm/versions/node/v22.0.0/bin/node
  Yarn:
    version: 1.22.19
    path: /opt/homebrew/bin/yarn
  npm:
    version: 10.5.1
    path: ~/.nvm/versions/node/v22.0.0/bin/npm
  Watchman:
    version: 2025.04.14.00
    path: /opt/homebrew/bin/watchman
Managers:
  CocoaPods:
    version: 1.15.2
    path: /Users/amandhiman/.rvm/gems/ruby-2.7.5/bin/pod
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 24.2
      - iOS 18.2
      - macOS 15.2
      - tvOS 18.2
      - visionOS 2.2
      - watchOS 11.2
  Android SDK:
    Android NDK: 22.1.7171670
IDEs:
  Android Studio: 2024.3 AI-243.26053.27.2432.13536105
  Xcode:
    version: 16.2/16C5032a
    path: /usr/bin/xcodebuild
Languages:
  Java:
    version: 23.0.1
    path: /usr/bin/javac
  Ruby:
    version: 2.7.5
    path: /Users/amandhiman/.rvm/rubies/ruby-2.7.5/bin/ruby
npmPackages:
  "@react-native-community/cli":
    installed: 19.0.0
    wanted: 19.0.0
  react:
    installed: 19.1.0
    wanted: 19.1.0
  react-native:
    installed: 0.80.0
    wanted: 0.80.0
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: true
  newArchEnabled: true
iOS:
  hermesEnabled: true
  newArchEnabled: true

Stacktrace or Logs

 ❌ Not 16KB aligned
Checking: ./armeabi-v7a/libfbjni.so
  Align: 0x4
 ❌ Not 16KB aligned
Checking: ./x86/libfbjni.so
  Align: 0x4
  ❌ Not 16KB aligned
Checking: ./armeabi-v7a/libreactnative.so
  Align: 0x4
  ❌ Not 16KB aligned
Checking: ./x86/libreactnative.so
  Align: 0x4
❌ Not 16KB aligned
Checking: ./armeabi-v7a/libhermestooling.so
  Align: 0x4
  ❌ Not 16KB aligned
Checking: ./armeabi-v7a/libhermes.so
  Align: 0x4
 ❌ Not 16KB aligned
Checking: ./x86/libhermestooling.so
  Align: 0x4
  ❌ Not 16KB aligned
Checking: ./x86/libhermes.so
  Align: 0x4
  ❌ Not 16KB aligned
Checking: ./armeabi-v7a/libjsi.so
  Align: 0x4
  ❌ Not 16KB aligned
Checking: ./x86/libjsi.so
  Align: 0x4

MANDATORY Reproducer

https://github.com/amanchd16/taxy

Screenshots and Videos

High Impact Issue:

• Affects ALL React Native Android apps
• Google Play Store shows warnings about 16KB page size compatibility
• Apps may crash on devices with 16KB page sizes
• Future Android versions may reject apps without 16KB compatibility
• Affects app distribution and user experience

16KB Libs.pdf

[alanleedev]

"16 KB pages are only supported on arm64 targets with 16 KB kernels. " from https://source.android.com/docs/core/architecture/16kb-page-size/16kb

Why do you think we need to support 16KB for ARMv7?
Could you share the exact Google Play Store warnings that you are seeing?

[alanleedev]

https://developer.android.com/guide/practices/page-sizes
--> "Starting November 1st, 2025, all new apps and updates to existing apps submitted to Google Play and targeting Android 15+ devices must support 16 KB page sizes on 64-bit devices."

[jvenene]

Alan, I saw in the React Native 0.77 announcement that building for 16 KB page size is now supported and is currently opt-in. Do you have a timeline for when it will be the default for new RN apps? I'm wondering because the Play Store requirement is coming up in a few months.

[alanleedev]

@jvenene It is ready since 0.77 and there is no opt-in.
Opt-in here means that developers needed to opt-in to actually enable 16KB page size for testing on selected Android 15 devices; https://reactnative.dev/blog/2025/01/21/version-0.77#android-version-15-support--16kb-page-support)

[alanleedev]

@amanchd16 I am closing this issue but do comment if you still see a problem.

[kiet-ap]

@amanchd16
You only need to care about arm64-v8a and x86_64 and in 0.77, react native .so files are all aligned.

If any arm64-v8a or x86_64 shared libraries are UNALIGNED, you'll need to update the packaging for those libraries, then recompile your app and retest by following the steps in this section.

[davidch-lqc]

In android/app/build.gradle, add this:

android {
    defaultConfig {
        ndk {
            abiFilters "arm64-v8a", "x86_64"
        }
    }
}

Not 100% sure though.. have to test if it works first

Sources:

• https://developer.android.com/google/play/requirements/64-bit
• https://stackoverflow.com/questions/54476308/support-to-64-bit-gives-error-on-adding-ndk-abifilters-in-build-gradle

[BogdanRad]

In android/app/build.gradle, add this:

android {
    defaultConfig {
        ndk {
            abiFilters "arm64-v8a", "x86_64"
        }
    }
}

Not 100% sure though.. have to test if it works first

Sources:

• https://developer.android.com/google/play/requirements/64-bit
• https://stackoverflow.com/questions/54476308/support-to-64-bit-gives-error-on-adding-ndk-abifilters-in-build-gradle

It's not working.. :(

[shuo-hiwintech]

How to support 16KB Page Size?

[parthshiroya6]

If you upgrade to Android 36 (targetSdkVersion 36) and encounter errors like:

then add the following configuration in your android/app/build.gradle file to exclude the problematic libraries:

android {
    ndkVersion rootProject.ext.ndkVersion
    buildToolsVersion rootProject.ext.buildToolsVersion
    compileSdk rootProject.ext.compileSdkVersion

    packagingOptions {
        // Add these lines to handle 16KB page size issue
        jniLibs {
            useLegacyPackaging = true
        }

        // Exclude problematic libraries if needed
        exclude "lib/x86_64/libandroidlame.so"
        exclude "lib/x86_64/libucrop.so"
    }
}

...

[Abhishek-Tripathy]

If you are using react-native-pdf, then the pdfium will also give you 16kb error, in that case open the node modules of this package and go into android then build.gradle, there go to bottom and change this

implementation 'io.legere:pdfiumandroid:1.0.33

earlier whatever version you have might give you that error, change to this and you are good to go, just remember to have ndk 28+

[gkasireddy202]

@parthshiroya6 - I added this line to my project, and my project has the following version.
buildToolsVersion = "35.0.0"
minSdkVersion = 24
compileSdkVersion = 35
targetSdkVersion = 35
ndkVersion = "27.1.12297006"
kotlinVersion = "2.0.21"
The 16KB warning pop-up has disappeared after I added this code to my project.
I am facing this issue with the react-native-compressor library. This library does not support 16KB.
Can I proceed to upload my AAB to the Google Play Store?
Will the 16 KB warning disappear after I upload the app to the Play Store in the Google Play Console?

packagingOptions {
// Add these lines to handle 16KB page size issue
jniLibs {
useLegacyPackaging = true
}

    // Exclude problematic libraries if needed
    exclude "lib/x86_64/libandroidlame.so"
}

}