How to enable OpenCL extensions?

Question

I am trying to enable the OpenCL extension cl_khr_gl_depth_images to make the following work:

glGenRenderbuffers(1, &gl_depthbuffer);
glBindRenderbuffer(GL_RENDERBUFFER, gl_depthbuffer);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT32F, width, height);
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, gl_depthbuffer);

...

cl_depth = clCreateFromGLRenderbuffer(context, CL_MEM_READ_ONLY, gl_depthbuffer, &error);

At the moment I am getting the following error from the clCreateFromGLRenderbuffer call CL_INVALID_IMAGE_FORMAT_DESCRIPTOR.

I added the following lines to the top of my cpp file:

#include <CL/cl.hpp>

#pragma OPENCL EXTENSION cl_khr_gl_sharing : enable
#pragma OPENCL EXTENSION cl_khr_gl_depth_images : enable

But my compiler gives two unknown pragma warnings and I am still getting the CL_INVALID_IMAGE_FORMAT_DESCRIPTOR error.

Am I including the extensions wrong or can one not use depth-renderbuffers in opencl?

Edit: My Device is supporting the extensions in question! The specification!

Answer 1

As doqtor already pointed out, put the lines

#pragma OPENCL EXTENSION cl_khr_gl_sharing : enable
#pragma OPENCL EXTENSION cl_khr_gl_depth_images : enable

at the top of your OpenCL C source code and not in your C++ code.

The C++ part of all available extensions is enabled by default and the required functions of the extension are automatically compiled into the executable.