Odd crash when trying to init/shutdown multiple times

[slewicki]

I know I've already asked quite a bit of questions in here already, so let me take the time to thank you all for an outstanding library and a great community.

I've ported over some of my OpenGL functionality into BGFX and am noticing a crash in BGFX when we execute our unit tests. Our unit tests run in a way that setup and tear down our system multiple times to test proper initialization and shutdown. This was setup using an OpenGL context within a GLFW window.

With the transition to BGFX I've noticed that the first test will run with no issue, but the second test crashes. I tried to isolate the test that caused the crash and running the test by itself passes. I created a basic sample program that initializes a GLFW window and inits BGFX before shutting down and repeating the process (Which can be found below). I noticed the crash was caused from an existing issue and tried to try again with multi-threading disabled and get a different crash of BGFX_FATAL(NULL != m_hdc, Fatal::UnableToInitialize, "GetDC failed!");

Any advice would be greatly appreciated

#include <bgfx/bgfx.h>
#include <bgfx/platform.h>
#include <bx/bx.h>
#include <bx/math.h>

#define GLFW_EXPOSE_NATIVE_WIN32

#include <GLFW/glfw3.h>
#include <GLFW/glfw3native.h>

#include <iostream>

GLFWwindow* window;

static void glfw_errorCallback(int error, const char* description)
{
  fprintf(stderr, "GLFW error %d: %s\n", error, description);
}

int Init(bgfx::RendererType::Enum type)
{
  // Create a GLFW window without an OpenGL context.
  glfwSetErrorCallback(glfw_errorCallback);
  if (!glfwInit())
  {
  fprintf(stderr, "GLFW error callback failed to get set\n");
  return 1;
  }

  glfwWindowHint(GLFW_CLIENT_API, GLFW_NO_API);

  window = glfwCreateWindow(640, 480, "BGFX Test Visualizer", nullptr, nullptr);
  if (!window)
  {
  fprintf(stderr, "GLFW window was not created\n");
  return 1;
  }

  // Initialize bgfx using the native window handle and window resolution.
  bgfx::Init init;
  init.platformData.nwh = glfwGetWin32Window(window);

  int width, height;
  glfwGetWindowSize(window, &width, &height);
  init.type = type;
  init.resolution.width = (uint32_t)width;
  init.resolution.height = (uint32_t)height;
  init.resolution.reset = BGFX_RESET_VSYNC;
  if (!bgfx::init(init))
  {
    fprintf(stderr, "Failed to initialize BGFX\n");
    return 1;
  }

  return 0;
}

void Finalize()
{
  bgfx::shutdown();
  glfwTerminate();
  window = NULL;
}

int main()
{
  int errorCode = Init(bgfx::RendererType::OpenGL);
  if (errorCode)
  {
    return errorCode;
  }

  while (!glfwWindowShouldClose(window))
  {
    glfwPollEvents();
  }
  Finalize();

  errorCode = Init(bgfx::RendererType::OpenGL);
  if (errorCode)
  {
    return errorCode;
  }

  while (!glfwWindowShouldClose(window))
  {
    glfwPollEvents();
  }
  Finalize();

  return 0;
}

[evilduck41]

I had this issue and found I had to compile with BGFX_CONFIG_MULTITHREADED=0 for the bgfx project. Apparently mulithread doesn't like this cycle and the renderFrame before init still doesn't shut off multithreading code.