Description of the problem / feature request:

Given the following BUILD file:

cc_binary(
    name = "hello",            
    srcs = ["hello.c"],        
    no_such_attribute = None,
)

I would expect some sort of error to be printed. There is an error if the invalid attribute is set to some non-None value (0, False, whatever) but None is just silently ignored.

A warning would also be acceptable (backwards compatibility and all), maybe with a flag to make it a hard error (defaulting to true in the next breaking release).

This behavior happens for both built-in and Starlark-defined rules.

What operating system are you running Bazel on?

macOS

What's the output of bazel info release?

release 2.2.0