Invalid value accepted for `#[macro_export(local_inner_macros)]`

[theemathas]

The reference seems to indicate that #[macro_export(local_inner_macros)] does not accept additional values for local_inner_macros. However, the following code currently compiles without errors.

#[macro_export(local_inner_macros(false))]
macro_rules! foo {
    () => {};
}

#[macro_export(local_inner_macros = false)]
macro_rules! bar {
    () => {};
}

As far as I can tell, the false value is entirely ignored, making the attributes equivalent to just #[macro_export(local_inner_macros)]. (The same is true when using string literals and numerical literals instead of false.)

I think this code should probably be rejected.

The parsing of this attribute was ported to the new attribute parsing infrastructure in #143857.

cc @JonathanBrouwer @jdonszelmann @Periodic1911

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Reproducible on the playground with version 1.96.0-nightly (2026-04-07 c756124775121dea0e64)