[SOLVED] OpenAL application crashes/hangs when I pass non-nullptr to `alBufferData()` from native code

I'm trying to play some sound on Android using OpenAL and C/C++. I'm using SDL framework.

I keep getting mysterious crashes with alBufferData() even when my code is as simple as:

ALuint buf, src;
alGenBuffers(1, &buf);
alGenSources(1, &src);
uint8_t data[8000]{};
alBufferData(buf, AL_FORMAT_MONO8, data, 8000, 8000);
alSourcei(src, AL_BUFFER, buf);
alSourcePlay(src);

Every time the program reaches alBufferData() it crashes or hangs. I'm not getting any kind of error message.

Surprisingly enough, if I pass 0 instead of actual pointer to alBufferData(), then the program runs fine and plays some random noise.

I have absolutely no idea what's wrong.

MCVE:

#include <cstdlib>
#include <cmath>
#include <string>

#include <SDL2/SDL.h>
#include <AL/al.h>
#include <AL/alc.h>

#if !defined(ANDROID) && !defined(__ANDROID__)
#define GLEW_STATIC
#include <GL/glew.h>
#else
#include <GLES2/gl2.h>
#endif

void Msg(const char *txt)
{
    SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_INFORMATION, "test app", txt, 0);
}
void Err(const char *txt)
{
    Msg(txt);
    std::exit(0);
}

int SDL_main(int, char **)
{
    Msg("Running build compiled at " __DATE__ " " __TIME__);

    if (SDL_Init(SDL_INIT_EVENTS | SDL_INIT_VIDEO))
        Err("SDL init failed");
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
    #if !defined(ANDROID) && !defined(__ANDROID__)
    SDL_Window *win = SDL_CreateWindow("test app", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 800, 600, SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);
    #else
    SDL_Window *win = SDL_CreateWindow("test app", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 800, 600, SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_FULLSCREEN);
    #endif
    if (!win)
        Err("Window creation failed");
    SDL_GLContext con = SDL_GL_CreateContext(win);
    if (!con)
        Err("OpenGL context creation failed");
    #if !defined(ANDROID) && !defined(__ANDROID__)
    glewExperimental = 1;
    if (glewInit() != GLEW_OK)
        Msg("GLEW init failed");
    while (glGetError()) {}
    #endif
    SDL_GL_SetSwapInterval(1);

    ALCdevice *device = alcOpenDevice(0);
    if (!device)
        Err("OpenAL init failed");
    const ALCint config_array[] = {ALC_FREQUENCY, 44100, ALC_MONO_SOURCES, 4, ALC_STEREO_SOURCES, 4, 0};
    ALCcontext *context = alcCreateContext(device, config_array);
    if (!context)
        Err("OpenAL context creation failed");
    if (!alcMakeContextCurrent(context))
        Err("OpenAL context switching failed");


    uint8_t sound_wave[8000];
    for (int i = 0; i < 8000; i++)
    {
        float pi = std::atan(1)*4;
        sound_wave[i] = int(std::pow(std::sin(i * pi / 180 * 4),0.5) * 127) + 127;

        auto smoothstep = [](float x){return 2*x*x*x-3*x*x;};
        if (i < 1000)
            sound_wave[i] *= smoothstep(i / 1000.f);
        else if (i >= 7000)
            sound_wave[i] *= smoothstep((8000 - i) / 1000.f);
    }

    ALuint buf, src;
    int frames = 0;

    while (1)
    {
        SDL_Event event;
        bool click = 0;
        while (SDL_PollEvent(&event))
        {
            switch (event.type)
            {
              case SDL_QUIT:
                std::exit(0);
                break;
              case SDL_KEYDOWN:
                click = 1;
                break;
            }
        }

        switch (frames)
        {
          case 3:  Msg("Creating a buffer");   break;
          case 4:  alGenBuffers(1, &buf); if (!buf) Err("No buffer"); break;
          case 5:  Msg("Creating a source");   break;
          case 6:  alGenSources(1, &src); if (!src) Err("No source"); break;
          case 7:  Msg("Setting buffer data"); break;
          case 8:
            alBufferData(buf, AL_FORMAT_MONO8, sound_wave, 8000, 8000);
            if (int err = alGetError()) // This code is not reached
                Msg((std::string("Error code: ") + std::to_string(err)).c_str());
            break;
          case 9:  Msg("Attaching buffer");    break;
          case 10: alSourcei(src, AL_BUFFER, buf);  break;
          case 11: Msg("Done");                break;
        }
        if (frames < 12)
            frames++;

        if (frames == 12 && click)
            alSourcePlay(src);

        SDL_GL_SwapWindow(win);
    }
}

Here is my Application.mk:

APP_ABI := armeabi armeabi-v7a x86 mips

APP_STL := c++_shared

LOCAL_SHARED_LIBRARIES := c++_shared
APP_CFLAGS += -w
APP_CPPFLAGS += -fexceptions -frtti -I../lib/include
APP_CPPFLAGS += -std=c++14 -O3 -s
NDK_TOOLCHAIN_VERSION := clang

I'm using OpenAL which was prebuilt using standalone toolchains. I don't know if it matters, but here is my build command (this one is for armv7-a, for other ABIs there are different commands):

cmake -D CMAKE_SYSTEM_NAME:string=android -D CMAKE_C_COMPILER:filepath="Y:/clang_3.8_android_api12_androideabi/bin/arm-linux-androideabi-clang.cmd" ^
                                          -D CMAKE_CXX_COMPILER:filepath="Y:/clang_3.8_android_api12_androideabi/bin/arm-linux-androideabi-clang++.cmd" ^
                                          -D CMAKE_C_FLAGS:string="-w -O3 -mthumb -march=armv7-a -mfloat-abi=softfp -mfpu=vfpv3-d16" ^
                                          -D CMAKE_CXX_FLAGS:string="-w -O3 -mthumb -march=armv7-a -mfloat-abi=softfp -mfpu=vfpv3-d16" ^
                                          -D CMAKE_SHARED_LINKER_FLAGS:string="-lc++_shared" ^
                                          -D CMAKE_MODULE_LINKER_FLAGS:string="-lc++_shared" ^
                                          -D CMAKE_BUILD_TYPE:string="Release" ^
                                          -G "MinGW Makefiles" ^
                                          ../../..
mingw32-make.exe

EDIT:

Now it's getting more interesting. I've managed to make it work once, but after a tiny unrelated change to the source code it broke again.

There MUST be some kind undefined behaviour somewhere, but I'm sure it's not on my side.

Is it a bug in OpenAL? The exact version I'm using is openal-soft-1.17.1.

EDIT:

Updated to OpenAL 1.17.2. No luck, same error.

EDIT:

Here is logcat output for the mcve from the emulator.
It's hosted externally because it's 2000+ lines long.

If I understood correctly, the log says that there is a heap corruption and that that application had sigsegv'ed in dlmalloc(). But I have no idea how to fix it.

I've tried to add SDL_INIT_AUDIO flag to SDL_Init() - same error.