Unable to build lime with android ndk r28

[tobil4sk]

Two of our dependencies fail to build with android ndk r28:

openal:

./lib/openal/al/event.cpp:189:9: warning: ignoring temporary created by a constructor declared with 'nodiscard' attribute [-Wunused-value]
  189 |         std::lock_guard<std::mutex>{context->mEventCbLock};
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning generated.
Error: ./lib/openal/common/almalloc.cpp:24:12: error: use of undeclared identifier 'aligned_alloc'
   24 |     return aligned_alloc(alignment, size);
      |            ^
1 error generated.

sdl:

Error: ./lib/sdl/src/sensor/android/SDL_androidsensor.c:174:9: error: 'ALooper_pollAll' is unavailable: obsoleted in Android 1 - ALooper_pollAll may ignore wakes. Use ALooper_pollOnce instead. See The API documentation for more information
  174 |     if (ALooper_pollAll(0, NULL, &events, (void**)&source) == LOOPER_ID_USER) {
      |         ^
/home/tobil/Dev/Android/SDK/ndk/r28/toolchains/llvm/prebuilt/linux-x86_64/bin/../sysroot/usr/include/android/looper.h:234:5: note: 'ALooper_pollAll' has been explicitly marked unavailable here
  234 | int ALooper_pollAll(int timeoutMillis, int* outFd, int* outEvents, void** outData)
      |     ^
1 error generated.

[tobil4sk]

Note, these issues also happen with r27c, which is currently the oldest ndk version that's still in support: https://github.com/android/ndk/wiki#releases

[joshtynjala]

We recently updated the 8.3.0-Dev branch to use SDL 2.30.12. I wonder if that version supports NDK r27 and r28? That was the newest SDL2 update at the time, but it looks like there may be a couple of newer SDL2 updates since then that we could try.

[dimensionscape]

aligned_alloc is introduced in sdk 28, so make sure the minSdkVersion is set to 28.

The sdl issue is due to ALooper_pollAll being obsolete. ALooper_pollOnce should be used instead. Cursory glance at sdl 2.30 shows they made the change here: https://github.com/libsdl-org/SDL/blob/9464f334b5637649fed69680dbc90250c91111b3/src/sensor/android/SDL_androidsensor.c#L164

So we should be ok

[tobil4sk]

aligned_alloc is introduced in sdk 28, so make sure the minSdkVersion is set to 28.

For some reason, with any ndk >= 20, hxcpp seems to ignore the PLATFORM define and instead reads the PLATFORM_NUMBER, which is later used to set PLATFORM internally.

https://github.com/HaxeFoundation/hxcpp/blob/dd050c019a85f4a12c9955265c82ec0e3307466d/tools/hxcpp/Setup.hx#L516-L527

https://github.com/HaxeFoundation/hxcpp/blob/dd050c019a85f4a12c9955265c82ec0e3307466d/toolchain/android-toolchain-clang.xml#L6

https://github.com/HaxeFoundation/hxcpp/blob/dd050c019a85f4a12c9955265c82ec0e3307466d/toolchain/android-toolchain-clang.xml#L31

The hxcpp setup seems a bit messy, but either way, replacing PLATFORM=android-28 with PLATFORM_NUMBER=28 would do what lime needs.

With this flag set and with the 8.3.0-Dev branch for the newer sdl, I am able to build the ndll successfully, thanks!