How to append a select of Label to a select of list?

[ivwumupy]

Hi, I'm writing a wrapper of cc_binary:

def _my_binary(name, linker_script, additional_linker_inputs, *kwargs):
    cc_binary(
        name = name,
        # What to do here???
        *kwargs,
    )
my_binary = macro(implementation = _my_binary, ..., inherit_attrs = cc_binary)

I want to append linker_script (a Label) to additional_linker_inputs (a list of Labels). But Bazel keeps complaining about selects.

Failed attempts:

1. additional_linker_inputs = additional_linker_inputs + [linker_script].
   Error: Error in cc_binary: expected value of type 'string' for element 0 of attribute 'additional_linker_inputs' of 'cc_binary', but got select
2. additional_linker_inputs = additional_linker_inputs + linker_script.
   Error: Error: Cannot combine incompatible types (select of list, select of Label)

Issue #8419 is related but I don't need to iterate over the select.

Any help would be appreciated.