/*

	 cl::CommandQueue::getInfo<CL_QUEUE_CONTEXT>() doesn't increase the
	 reference count of the cl::Context object returned by this method. This
	 results in a program crash when the destructur is called for the
	 unreferenced instance. The problem probably exists for other getInfo<...>
	 variants since the code is shared.

	 This file demonstrates the problem. The program crashes in 
	 ReferenceHandler<cl_context>::release(), which is invoked from
	 cl::Context::~Context(). If the context's reference count is increased
	 explicitly (by setting "#if 1" in line 47), the program finishes without
	 error.

*/

#include <iostream>

#define __CL_ENABLE_EXCEPTIONS
#include <CL/cl.hpp>

using namespace std;


int
test_opencl_bug()
{
	try {
		// get list of platforms and devices:
		vector<cl::Platform> platforms;
		vector<cl::Device> devices;
		cl::Platform::get(&platforms);
		platforms[0].getDevices(CL_DEVICE_TYPE_ALL, &devices);
		
		// create a context:
		cl::Context context(devices);

		// create a command queue:
		cl::CommandQueue queue(context, devices[0], 0);

		// print current context reference count:
		cout << "ref count = " << context.getInfo<CL_CONTEXT_REFERENCE_COUNT>() << endl;

		// access context associated with command queue:
		cl::Context context2(queue.getInfo<CL_QUEUE_CONTEXT>());

#if 0
		// If the context's reference count is increased explicitly at this point,
		// the program finishes without error:
		::clRetainContext(context2());
#endif

		cout << "ref count = " << context.getInfo<CL_CONTEXT_REFERENCE_COUNT>() << endl;
	}
	catch(cl::Error err) {
		cerr << "ERROR: " << err.what() << "(" << err.err() << ")" << endl;
	}

	return EXIT_SUCCESS;
}