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Build tflite c++ lib for android with ndk 25 > with bazel

I'm building a huge project that requires ndk versions above 25 (I'm using 25.0.8775105 right now). And I would like to use TFLite on my project. Following the docs, to cross-compile it on my x86-64 machine to be suitable for arm64-v8a architectures the instructions goes as follows:
Get tensorflow source
Install bazel (I've tried both 6.0.0 and the 7.0.0-prebuild)
Run ./configure and say y to Would you like to interactively configure ./WORKSPACE for Android builds?, then configure it.
Run bazel build -c opt --config=android_arm64 //tensorflow/lite:libtensorflowlite.so
Extract the .so file and get the header files than use like any other library.
When I run ./configure and say yes to configuring ./WORKSPACE, it wants me to provide an ndk directory. However, when I provide it (it being /home/tb/Android/Sdk/ndk/25.0.8775105 on my system, very similar to what's recommended) I get hit with this: WARNING: The NDK version in /home/tb/Android/Sdk/ndk/25.0.8775105 is 25, which is not supported by Bazel (officially supported versions: [19, 20, 21]). Please use another version. Compiling Android targets may result in confusing errors. followed by an error caused by this:
Traceback (most recent call last):
File "/home/tb/Desktop/tensorflow/tensorflow_src/./configure.py", line 1363, in <module>
main()
File "/home/tb/Desktop/tensorflow/tensorflow_src/./configure.py", line 1336, in main
create_android_ndk_rule(environ_cp)
File "/home/tb/Desktop/tensorflow/tensorflow_src/./configure.py", line 653, in create_android_ndk_rule
get_ndk_api_level(environ_cp, android_ndk_home_path))
File "/home/tb/Desktop/tensorflow/tensorflow_src/./configure.py", line 747, in get_ndk_api_level
api_levels = sorted(os.listdir(platforms))
FileNotFoundError: [Errno 2] No such file or directory: '/home/tb/Android/Sdk/ndk/25.0.8775105/platforms'
I've tried compiling it with bazel build -c opt //tensorflow/lite:libtensorflowlite.so --fat_apk_cpu=arm64-v8a which did in fact built the .so file, but when I try to build the code it says C/C++: ld: error: undefined symbol: tflite::impl::Interpreter::Invoke(), I did run my project on linux and it works fine, android uses a similar if not the same cmake file so I think the .so is broken.
What should I do? Does anyone have a link to, preferably official, pre-built tflite aarch64 / arm64-v8a .so file for c++?
Update: I've opened an issue detailing everything I've tried up to now.

Error when attempting to configure cmake for cross compilation to android

I have been trying to build a c++ library for android using cmake cross compilation.
The library itself is a trivial test I made purely for testing the androind build process.
I have been using the cmake gui (v 3.25.0) on a windows machine.
I use a visual studio 2019 generator in cmake and specify a toolchain file.
Unfortunately, I seem to get the same error whatever I try. I tried searching for similar problems and trouble shooting, but have so far been unable to make any progress. If anyone with more experience could lend a hand, I would be very grateful!
I have attempted setting many different variables in the toolchain file in an attempt to resolve the problem, but the basic version of what I am working with is:
set(CMAKE_SYSTEM_NAME Android)
set(CMAKE_ANDROID_ARCH_ABI armeabi-v7a)
set(CMAKE_ANDROID_NDK C:/Microsoft/AndroidNDK64/android-ndk-r16b/)
The error I run into happens whenever I configure cmake. The outut I get from cmake looks something like this:
Android: Targeting API '27' with architecture 'arm', ABI 'armeabi-v7a', and processor 'armv7-a'
Android: Selected Clang toolchain 'arm-linux-androideabi-clang' with GCC toolchain 'arm-linux-androideabi-4.9'
The C compiler identification is Clang 5.0.300080
The CXX compiler identification is Clang 5.0.300080
Detecting C compiler ABI info
Detecting C compiler ABI info - failed
Check for working C compiler: C:/Microsoft/AndroidNDK64/android-ndk-r16b//toolchains/llvm/prebuilt/windows-x86_64/bin/clang.exe
Check for working C compiler: C:/Microsoft/AndroidNDK64/android-ndk-r16b//toolchains/llvm/prebuilt/windows-x86_64/bin/clang.exe - broken
CMake Error at C:/Program Files/CMake/share/cmake-3.25/Modules/CMakeTestCCompiler.cmake:70 (message):
The C compiler
"C:/Microsoft/AndroidNDK64/android-ndk-r16b//toolchains/llvm/prebuilt/windows-x86_64/bin/clang.exe"
is not able to compile a simple test program.
It fails with the following output:
Change Dir: C:/Users/username/Documents/Code Projects/Android Test/build/CMakeFiles/CMakeScratch/TryCompile-zqgcqm
Run Build Command(s):C:/Program Files (x86)/Microsoft Visual Studio/2019/Community/MSBuild/Current/Bin/MSBuild.exe cmTC_b0f1d.vcxproj /p:Configuration=Debug /p:Platform=x64 /p:VisualStudioVersion=16.0 /v:m && Microsoft (R) Build Engine version 16.11.2+f32259642 for .NET Framework
Copyright (C) Microsoft Corporation. All rights reserved.
ANDROID_HOME=C:\\Microsoft\AndroidSDK\25
ANT_HOME=C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Apps\apache-ant-1.9.3
JAVA_HOME=C:\Program Files\Eclipse Foundation\jdk-8.0.302.8-hotspot
NDK_ROOT=C:\\Microsoft\AndroidNDK64\android-ndk-r16b
testCCompiler.c
clang.exe : warning : argument unused during compilation: '-mthumb' [-Wunused-command-line-argument] [C:\Users\username\Documents\Code Projects\Android Test\build\CMakeFiles\CMakeScratch\TryCompile-zqgcqm\cmTC_b0f1d.vcxproj]
clang.exe : warning : argument unused during compilation: '-mfpu=vfpv3-d16' [-Wunused-command-line-argument] [C:\Users\username\Documents\Code Projects\Android Test\build\CMakeFiles\CMakeScratch\TryCompile-zqgcqm\cmTC_b0f1d.vcxproj]
clang.exe : warning : argument unused during compilation: '-mfloat-abi=softfp' [-Wunused-command-line-argument] [C:\Users\username\Documents\Code Projects\Android Test\build\CMakeFiles\CMakeScratch\TryCompile-zqgcqm\cmTC_b0f1d.vcxproj]
CLANGCOMPILE : error : unknown target CPU 'armv7-a' [C:\Users\username\Documents\Code Projects\Android Test\build\CMakeFiles\CMakeScratch\TryCompile-zqgcqm\cmTC_b0f1d.vcxproj]
CMake will not be able to correctly generate this project.
Call Stack (most recent call first):
CMakeLists.txt:4 (project)
Configuring incomplete, errors occurred!
I initially used used the NDK version found in the android tools for visual studio found at: "C:/Microsoft/AndroidNDK64/android-ndk-r16b/"
as an NDK version.
I have also tried directly downloading the latest version of the NDK and pointing to that with CMAKE_ANDROID_NDK in the toolchain file, though this did not seem to make any change.
I have tried directly using the toolchain.cmake files found at "NDK/build/cmake/android.toolchain.cmake"
for both the NDK versions described above. This too gave the same error.
Any ideas what could be causing this or how to fix?

Ok, so I was misunderstanding a few things about cross-compiling to android.
First, if I want to be able to use the static library (e.g in android studio), I will need to generate and build a solution for more than one android ABI.
The ABI's to build for are: armeabi-v7a, arm64-v8a, x86_64, x86. I then need to check for each android ABI in the CMakeLists.txt file of Android studio (e.g. elseif(ANDROID_ABI STREQUAL arm64-v8a)) and swap out the location of the library to import to the build folder of that particular ABI.
As far as I am aware, it is unfortunately not possible to generate for all these ABI's as seperate platforms within the same visual studio solution. Given that, cmake must be run 4 seperate times to different build folders, each time targeting a different ABI and generator platform. To save the hassle of doing this manually, creating a batch (.bat) script to automate the process seems the best way to go. This will involve using cmake from the command line instead of the GUI version. The script can also be made to build the generated projects to save opening each one in visual studio and building there.
The batch script I have made to generate and build cross-compilation projects for android is as follows:
#echo OFF
set BUILD_DIR=build
set ANDROID_NDK=C:\Microsoft\AndroidNDK\android-ndk-r23c
set GENERATOR="Visual Studio 17 2022"
set CMAKE_GENERATOR=-G %GENERATOR%
set CMAKE_TOOLCHAIN_FILE=-DCMAKE_TOOLCHAIN_FILE=%ANDROID_NDK%\build\cmake\android.toolchain.cmake
set CMAKE_SYSTEM_NAME=-DCMAKE_SYSTEM_NAME=Android
set EXTRA_CMAKE_ARGS=-DBUILD_SHARED_LIBS=true -DANDROID_TOOLCHAIN=clang -DANDROID_STL=c++_static
CALL :build_android armeabi-v7a ARM 16
CALL :build_android arm64-v8a ARM64 21
CALL :build_android x86_64 x64 21
CALL :build_android x86 x86 16
EXIT /B %ERRORLEVEL%
:build_android
set ABI_VERSION=%~1
set GENERATOR_PLATFORM=%~2
set MINIMUM_API_LEVEL=%~3
set CMAKE_ANDROID_ARCH_ABI=-DANDROID_ABI=%ABI_VERSION%
set ABI_BUILD_DIR=%BUILD_DIR%\%ABI_VERSION%
set CMAKE_GENERATOR_PLATFORM=-A %GENERATOR_PLATFORM%
set CMAKE_BUILD_DIR=-B %ABI_BUILD_DIR%
set CMAKE_MIN_API=-DANDROID_PLATFORM=android-%MINIMUM_API_LEVEL%
set CMAKE_ARGS=%CMAKE_BUILD_DIR% %CMAKE_ANDROID_ARCH_ABI% %CMAKE_GENERATOR% %CMAKE_GENERATOR_PLATFORM% %CMAKE_SYSTEM_NAME% %CMAKE_TOOLCHAIN_FILE% %CMAKE_MIN_API%
echo building for android ABI: %ABI_VERSION%
echo cmake arguments = %CMAKE_ARGS%
echo:
cmake %CMAKE_ARGS% %EXTRA_CMAKE_ARGS%
echo:
cmake --build %ABI_BUILD_DIR% --target ALL_BUILD
echo:
echo:
EXIT /B 0
This worked for my simple test library, but I guess depending on the project the arguments to the cmake commands may need to be tweaked.

Android NDK - Building Limbo Android returns fatal error: config.h: No such file or directory

I'm trying to rebuild Limbo Android. I'm on Linux Mint.
All I changed was android-config.mak NDK_ROOT, exported variables NDK_ROOT. I've also exported NDK_MODULE_PATH to /home/pathtoandroidndk/sources, as per README instructions.
From terminal I do cd limbo-android/jni and then make.
Building returns this error:
jni/glib/glib/./libcharset/localcharset.c:22:20: fatal error: config.h: No such file or directory
compilation terminated.
make: *** [obj/local/armeabi-v7a/objs-debug/glib-2.0/./libcharset/localcharset.o] Error 1
make: Leaving directory `/home/me/limbo-android'
I've tried modifing Android.mk following instructions from Android NDK - Additional Include Directories and Unable to find header files - Android NDK, without success.
I came to conclusion that each module inside limbo-android needs it's own config.h file, while libcharset does not have one.
How do I solve this error? Is there a generic config.h (the one from NDK maybe?)
NOTE: I can build it without any problems on Windows 8.1 using mingw.

cocos2d-x 3.0 rc0 : develop for android in eclipse

I'm on windows xp & Eclipse Kepler. I want to develop with cocos2d-x, but I have some problem.
First, I created project.
cocos new MyGame -p com.myprog.MyGame -l cpp -d MyGame
and I tried run:
cd MyGame
cocos run -s MyGame -p android
and it succeeded.
The problem happens when I open it by eclipse. I create eclipse project, Android Project From Existing Code.
But I can't know what to do next.. even I don't know how to build! (Project - Build doesn't work..)
Moreover, Classes, cocos2dx, extensions and scripting folder are broken..
I tried to find solution, but people are saying about only cocos2d-x 2.x ...
Even if README.md seems to say about 2.x!
Could anyone tell me how do I do?

Installation Process:
Cocos2d require NDK and Cygwin
First install NDK ->
This links may help you :
http://nikhilvithlani.blogspot.in/2013/07/install-android-ndk-for-windows_6.html
Cocos 2d installation link:
http://www.cocos2d-x.org/wiki/How_to_set_up_the_android_cocos2d-x_development_environment_on_Windows_7
Download cocos 2d version and follow the instruction in above link
This packages you required in cygwin: search and install:
autoconf, automake, binutils, gcc-core, gcc-g**, gcc4-core, gcc4-g**, gdb, pcre, pcre-devel, gawk, make
After installation cygwin,ndk and you need to config in C/C++ preference in eclipse(Don't forget to install c/c++ plugin in eclipse)
My NDK and PATH is :
NDK_ROOT->C:/android-ndk-r9c
PATH->C:\android-ndk-r9c;C:\Cygwin\bin;
Then import the sample project :
cocos2d-x-2.2.2\samples\Cpp\HelloCpp\proj.android
Import the library :
cocos2d-x-2.2.2\cocos2dx\platform\android\java
Add the library to hello world project
when you import hello world project eclipse automatically include the header files:
bash F:/cocos2d-x-2.2.2/samples/Cpp/HelloCpp/proj.android/build_native.sh
cygwin warning:
MS-DOS style path detected: F:\cocos2d-x-2.2.2\samples\Cpp\HelloCpp\proj.android
Preferred POSIX equivalent is: /cygdrive/f/cocos2d-x-2.2.2/samples/Cpp/HelloCpp/proj.android
CYGWIN environment variable option "nodosfilewarning" turns off this warning.
Consult the user's guide for more details about POSIX paths:
http://cygwin.com/cygwin-ug-net/using.html#using-pathnames
NDK_ROOT = C:/android-ndk-r9c
COCOS2DX_ROOT = /cygdrive/f/cocos2d-x-2.2.2/samples/Cpp/HelloCpp/proj.android/../../../..
APP_ROOT = /cygdrive/f/cocos2d-x-2.2.2/samples/Cpp/HelloCpp/proj.android/..
APP_ANDROID_ROOT = /cygdrive/f/cocos2d-x-2.2.2/samples/Cpp/HelloCpp/proj.android
Using prebuilt externals
+ C:/android-ndk-r9c/ndk-build -C /cygdrive/f/cocos2d-x-2.2.2/samples/Cpp/HelloCpp/proj.android NDK_MODULE_PATH=/cygdrive/f/cocos2d-x-2.2.2/samples/Cpp/HelloCpp/proj.android/../../../..:/cygdrive/f/cocos2d-x-2.2.2/samples/Cpp/HelloCpp/proj.android/../../../../cocos2dx/platform/third_party/android/prebuilt
make: Entering directory '/cygdrive/f/cocos2d-x-2.2.2/samples/Cpp/HelloCpp/proj.android'
Android NDK: WARNING: APP_PLATFORM android-9 is larger than android:minSdkVersion 8 in ./AndroidManifest.xml
Android NDK: WARNING:/cygdrive/f/cocos2d-x-2.2.2/samples/Cpp/HelloCpp/proj.android/../../../../cocos2dx/Android.mk:cocos2dx_static: LOCAL_LDLIBS is always ignored for static libraries
[armeabi] Install : libhellocpp.so => libs/armeabi/libhellocpp.so
make: Leaving directory '/cygdrive/f/cocos2d-x-2.2.2/samples/Cpp/HelloCpp/proj.android'
After get output in console right click project and goto properties and choose paths and symbols under c/c++ general
Run the project and you can see the output :
Useful links:
http://www.youtube.com/watch?v=2itbQceTQGI

You can handle it in different way though you are on windows you have to use Microsoft Visual Studio Express 2012 for Windows Desktop its free and also it will give you good IntelliSense support.
Every time you edit using MS VS2012 run proj.android/build_native.py and then you can run your app from eclipse as usual.

Android ndk-build command does nothing

I have a similar question to that posted here:
Android NDK: why ndk-build doesn't generate .so file and a new libs folder in Eclipse?
...though I am running Windows 7, not Mac os. Essentially the ndk-build command is run, gives no error but doesn't create an .so file (also, since I'm on windows this should create a .dll and not an .so?). I tried running the command from the root, jni, src folders etc. but got the same result; cmd just returns to the prompter after a few seconds. I ran it again from the jni folder with NDK_LOG=1 parameter to see what was happening. Here is a portion of the transcript of the log results after running ndk-build in the jni folder (after it successfully identified the platform, etc.)...
Android NDK: Looking for jni/Android.mk in /workspace/NdkFooActivity/jni
Android NDK: Looking for jni/Android.mk in /workspace/NdkFooActivity
Android NDK: Found it !
Android NDK: Found project path: /workspace/NdkFooActivity
Android NDK: Ouput path: /workspace/NdkFooActivity/obj
Android NDK: Parsing /cygdrive/c/android-ndk-r8/build/core/default-application.mk
Android NDK: Found APP_PLATFORM=android-15 in /workspace/NdkFooActivity/project.properties
Android NDK: Application local targets unknown platform 'android-15'
Android NDK: Switching to android-14
Android NDK: Using build script /workspace/NdkFooActivity/jni/Android.mk
Android NDK: Application 'local' is not debuggable
Android NDK: Selecting release optimization mode (app is not debuggable)
Android NDK: Adding import directory: /cygdrive/c/android-ndk-r8/sources
Android NDK: Building application 'local' for ABI 'armeabi'
Android NDK: Using target toolchain 'arm-linux-androideabi-4.4.3' for 'armeabi' ABI
Android NDK: Looking for imported module with tag 'cxx-stl/system'
Android NDK: Probing /cygdrive/c/android-ndk-r8/sources/cxx-stl/system/Android.mk
Android NDK: Found in /cygdrive/c/android-ndk-r8/sources/cxx-stl/system
Android NDK: Cygwin dependency file conversion script:
...after which point it just runs the script mentioned in the last line, then terminates. Any ideas? Thanks!

Set up a builder. Refer to following article for how to do that:
http://maxters.net/2011/02/android-ndk-builder-for-eclipse-in-windows/
There is a "small" change beginning NDK r8 – Cygwin is not necessary anymore and I had a trouble when building native libraries with Cygwin and NDK r8 – there was some error message about cxx-stl...
Almost everything in the link above is OK, but leave Arguments in the Main tab blank and change Location to:
${env_var:ANDROID_NDK_ROOT}/ndk-build.cmd
I use system variable path ANDROID_NDK_ROOT, but you can provide a full path to the ndk-build.cmd.
Also, there is no need to set any variable in the Environment tab.
Set up your builder this way and you will be fine.
Just a note, Android is built on the top of the Linux OS, so even if you are on Windows you will get Linux libraries with .so extension.

Following link was instructive but missing a detail if you are configuring NDK support in Eclipse after CDT it already depricated (summer of 2017 already).
http://maxters.net/2011/02/android-ndk-builder-for-eclipse-in-windows/
Where you need to configure your external builder Location, instead of pointing to cygwin\bin\bash.exe and adding as Argument your ndk-build.cmd location this is what worked for me on Windows 7 and 10.
In "Edit Configuration" dialog for external builder do following:
- for Location -> specify where your "ndk-build.cmd" is. i.e "D:\Android\NDK\ndk-build.cmd"
- for Arguments -> just specify "all"

The NDK build system relies on wildcards to find the sources to compile. If you have a path wrong somewhere, it will find no sources and do nothing. Check Android.mk very carefully. More can't be said unless you post Android.mk and a description of the source tree.