// Loosely derived from http://www.altdevblogaday.com/2011/06/23/improving-opengl-error-messages/
static void debug_callback_arb(GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar *message, GLvoid *pUser_param);
+ static void debug_callback(GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar *message, GLvoid *pUser_param);
bool is_extension_supported(const char *pExt);