Blacklisting doesn't hide inner types, and the template analysis gets confused.

Input C/C++ Header

template <typename T>
struct Transform {
  T t;
};

template <typename A, typename B, typename C>
struct TransformOp {
  A a;
  B b;
  C c;
  struct InterpolateMatrix_Body {
    Transform<TransformOp<A, B, C>> from;
    Transform<TransformOp<A, B, C>> to;
    A a;
  };
};

Bindgen Invocation

$ ./target/debug/bindgen t.hpp --blacklist-type TransformOp --blacklist-type Transform

Actual Results

#[repr(C)]
pub struct TransformOp_InterpolateMatrix_Body<A> {
    pub from: Transform<TransformOp<A, B, C>>,
    pub to: Transform<TransformOp<A, B, C>>,
    pub a: A,
    pub _phantom_0: ::std::marker::PhantomData<::std::cell::UnsafeCell<A>>,
}

Which as you can see uses the types B, and C, which we forget to append to the aliases. I think blacklisting something should stop generating all the inner types, but not sure if anybody relies on that.

Reproduce the output from t.hpp with the shown bindgen invocation and blacklists for TransformOp and Transform. Trace how blacklisting interacts with the generated InterpolateMatrix_Body inner type and its aliases, then verify that the resulting bindings no longer produce the inconsistent A-only alias output.