From the OpenGL Registry:
"2012/08/13: specs named GL_ARB_debug_group, GL_ARB_debug_label, and
GL_ARB_debug_output2 were published in error during the initial OpenGL 4.3
release. All functionality in these documents was combined into
the extension GL_KHR_debug. They have been withdrawn from the registry,
and a few other extensions were renumbered to avoid holes in the numbering
scheme."
ARB_clear_buffer_object not started
ARB_compute_shader started (gallium)
ARB_copy_image not started
-ARB_debug_group not started
-ARB_debug_label not started
-ARB_debug_output DONE
-ARB_debug_output2 not started
+KHR_debug some work done (ARB_debug_output)
ARB_explicit_uniform_location not started
ARB_fragment_layer_viewport not started
ARB_framebuffer_no_attachments not started