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Problems attempting to build oboe c++ library using cmake on windows

I am attempting to build 'oboe' on a windows machine using cmake (version 3.25.0) and a visual studio generator. The end goal is to create a c++ audio library that uses oboe as the back end for android, but as a first step simply geting oboe to build is the plan.
I have managed to succesfully generate build and use a static library with a few simple test functions using the method described below, but I run into errors when attempting to build oboe.
I have also managed to get oboe to build by using the method described in the documentation and
doing add_subdirectory etc. in the CMakeLists file of android studio. However I am trying to generate/ build using cmake outside of android studio.
The oboe repo is found here: https://github.com/google/oboe
The toolchain file I am using is: 'android.toolchain.cmake' included in the NDK at the location: ndk version/build/cmake/android.toolchain.cmake
I use a batch script to automate generating/ building to several different android ABI's, inspired by a similar shell script included with the oboe repo 'build_all_android.sh'. The .bat script I made is shown below:
#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
When I run this using the ANDROID_NDK variable (line 3) pointing to the root of the up to date ndk that comes with the visual studio 2022 android tools, I get an error:
-- The C compiler identification is unknown
-- The CXX compiler identification is unknown
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - failed
-- Check for working C compiler: C:/Microsoft/AndroidNDK/android-ndk-r23c/toolchains/llvm/prebuilt/windows-x86_64/bin/clang.exe
-- Check for working C compiler: C:/Microsoft/AndroidNDK/android-ndk-r23c/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/AndroidNDK/android-ndk-r23c/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/user/Documents/Code Projects/oboe/build/x86/CMakeFiles/CMakeScratch/TryCompile-pp2ibg
Run Build Command(s):C:/Program Files/Microsoft Visual Studio/2022/Community/MSBuild/Current/Bin/amd64/MSBuild.exe cmTC_c21fb.vcxproj /p:Configuration=Debug /p:Platform=x86 /p:VisualStudioVersion=17.0 /v:m && MSBuild version 17.4.1+9a89d02ff for .NET Framework
ANDROID_HOME=C:\\Microsoft\AndroidSDK\25
ANDROID_SDK_ROOT=C:\\Microsoft\AndroidSDK\25
ANT_HOME=
JAVA_HOME=C:\Program Files\Android\jdk\jdk-8.0.302.8-hotspot\jdk8u302-b08
NDK_ROOT=C:\Microsoft\AndroidNDK\android-ndk-r23c
testCCompiler.c
In file included from <built-in>:349:
<command line>(1,9): warning : '__ANDROID_API__' macro redefined [-Wmacro-redefined] [C:\Users\user\Documents\Code Projects\oboe\build\x86\CMakeFiles\CMakeScratch\TryCompile-pp2ibg\cmTC_c21fb.vcxproj]
#define __ANDROID_API__ 1
^
<built-in>(342,9): note: previous definition is here
#define __ANDROID_API__ __ANDROID_MIN_SDK_VERSION__
^
1 warning generated.
ld: error: cannot open crtbegin_so.o: No such file or directory
ld: error: unable to find library -llog
ld: error: unable to find library -landroid
ld: error: cannot open crtend_so.o: No such file or directory
clang: error: linker command failed with exit code 1 (use -v to see invocation)
C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Microsoft\VC\v170\Application Type\Android\3.0\Android.Common.targets(125,5): error MSB6006: "clang.exe" exited with code 1. [C:\Users\user\Documents\Code Projects\oboe\build\x86\CMakeFiles\CMakeScratch\TryCompile-pp2ibg\cmTC_c21fb.vcxproj]
CMake will not be able to correctly generate this project.
and cmake fails to generate the project. I can actually get this to generate correctly, but only if I set the android NDK version within the cross-compilation options of visual studio to use the NDK bundled with my installation of Android studio, and also set the ANDROID_NDK variable of the batch script to point to the same root.
In this case, though cmake generates the project the build fails with a similar reason to the warning given above:
Building Custom Rule C:/Users/user/Documents/Code Projects/oboe/CMakeLists.txt
AAudioLoader.cpp
In file included from <built-in>:404:
<command line>(1,9): error : '__ANDROID_API__' macro redefined [-Werror,-Wmacro-redefined] [C:\Users\user\Documents\Co
de Projects\oboe\build\x86\oboe.vcxproj]
#define __ANDROID_API__ 16
^
<built-in>(394,9): note: previous definition is here
#define __ANDROID_API__ __ANDROID_MIN_SDK_VERSION__
^
1 error generated.
Thanks in advance for any help, it is much appreciated!

Your build fails because you instruct the compiler to view the warning '__ANDROID_API__' macro redefined as an error. And this warning seems to occur because Visual Studio still sets the macro __ANDROID_API__ instead of setting __ANDROID_MIN_SDK_VERSION__. I think that is a Visual Studio bug that was introduced when they started shipping the NDK 23 instead of 21.
EDIT:
This issue is being tracked here.

Android NDK fails to compile Telegram project

Android NDK compile fails at
[arm64-v8a] Install : libtmessages.29.so => libs/arm64-v8a/libtmessages.29.so
[armeabi-v7a] SharedLibrary : libtmessages.29.so
jni/./ffmpeg/armv7-a/libavutil.a(mem.o): In function `av_malloc':
mem.c:(.text+0x60): undefined reference to `posix_memalign'
collect2.exe: error: ld returned 1 exit status
make: *** [obj/local/armeabi-v7a/libtmessages.29.so] Error 1
Can anybody suggest me what's wrong with it.
I am using Android Studio 3.1.4.
NDK: android-ndk-r17c
Using Windows 7 32bit.
This happens while compiling on fresh download of Telegram source code from
git clone — recursive https://github.com/DrKLO/Telegram.git
First I thought this might be because of NDK, I tried with ndk-r16b with same error while ndk-r14b and r15b return
Android NDK: ERROR:jni/Android.mk:avutil: The LOCAL_SRC_FILES for a prebuilt library should only contain one item
G:/Softwares/android-ndk-r15c/build//../build/core/prebuilt-library.mk:28: *** missing separator. Stop.
If anybody has gone through this, please mention here what is the cause behind this and how we can do it.

Use ndk r16b.
Works fine with the latest changes at a724d96e
Found the answer here:
https://github.com/grishka/libtgvoip/issues/8#issuecomment-417647322

Android NDK sample build error linux

Hello I am new to Android and I am trying to build the hello-jni sample that is included in the NDK but I get the error below, any idea how to fix it?
15:57:10 ** Build of configuration Default for project HelloJni **
/media/Project/adt-bundle-linux-x86-20131030/adt-bundle-linux-x86-20131030/android-ndk-r9c/ndk-build
all Android NDK: WARNING: APP_PLATFORM android-19 is larger than
android:minSdkVersion 3 in ./AndroidManifest.xml [armeabi-v7a]
Compile thumb : hello-jni <= hello-jni.c arm-linux-androideabi-gcc:
error trying to exec
'/media/Project/adt-bundle-linux-x86-20131030/adt-bundle-linux-x86-20131030/android-ndk-r9c/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/as':
execv: Exec format error make: *
[obj/local/armeabi-v7a/objs/hello-jni/hello-jni.o] Error 1
15:57:10 Build Finished (took 230ms)
This is what I am using:
Ubuntu 10.04.4
ADT bundle for linux (v22.3.0-887826)
NDK r9c
Thanks in advance

The WARNING is correct, and should be ignored.
Regarding the gcc error, you probably have a problem with installation of NDK. How did you unpack it? Check
ls -l /media/Project/adt-bundle-linux-x86-20131030/adt-bundle-linux-x86-20131030/android-ndk-r9c/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/arm-linux-androideabi/bin/as
This should be a symbolic link to ../../bin/arm-linux-androideabi-as, and both should have executable permissions.

Android NDK arm-linux-androideabi-g++: error

I am trying to compile android-NDK project which uses L2CAP Bluetooth profile.When I compile in eclipse with android-ndk-r8d-windows and android-sdk-4.2 I am getting following error
arm-linux-androideabi-g++: error: libbluetooth.so: No such file or directory
make: *** [obj/local/armeabi/libl2cap_BTComm.so] Error 1
Please help me in solving this

I got the same problem in Ubuntu 12.04 while building the ndk project using ndk-build.
The problem is the missing g++ compiler. After install a GNU C++ compiler it works now.
Interestingly, when I recompile the whole project from fresh it got the same complain again.
(before I was using cygwin and ubuntu to compile the same project and it was working)

Its been over a year now since the last reply but I think the answer is to use the -l option of g++ to add the directory with the lib to g++'s search paths.

opencv.hpp not found in NDK build on Windows

I am getting some issues here while I am trying to compile my code with Cgywin.
$ /cygdrive/c/native_work/android-ndk-r8b/ndk-build
Android NDK: WARNING: Unsupported source file extensions in jni/Android.mk for module main
Android NDK: NotePaperDetector.hpp
Install : libmain.so => libs/armeabi-v7a/libmain.so
so how I can compile the .hpp file ?
Now as #mah you said I have removed it from my Android.mk but now its showing some different error -
$ /cygdrive/c/native_work/android-ndk-r8b/ndk-build
Compile++ thumb : main <= NotePaperDetector.cpp
In file included from jni/NotePaperDetector.hpp:4:0,
from jni/NotePaperDetector.cpp:1:
jni/NoteLocation.hpp:4:30: fatal error: opencv2/opencv.hpp: No such file or directory
compilation terminated.
/cygdrive/c/native_work/android-ndk-r8b/build/core/build-binary.mk:255: recipe for target `obj/local/armeabi-v7a/objs/main/NotePaperDetector.o' failed
make: *** [obj/local/armeabi-v7a/objs/main/NotePaperDetector.o] Error 1

With the latest NDK releases you don't need Cygwin at all.
By the way a GNU/Linux platform is always the best for Android developers.