Function egl_debug_proc 

unsafe extern "system" fn egl_debug_proc(
    error: Enum,
    command_raw: *const c_char,
    message_type: u32,
    _thread_label: *const c_void,
    _object_label: *const c_void,
    message_raw: *const c_char,
)

Available on gles and neither Windows nor webgl only.