improper_ctypes complains about types that contain PhantomData #34798
Description
#[repr(C)] pub struct Foo(::std::marker::PhantomData<i32>); extern { pub fn f(foo: *mut Foo); } fn main() {}warning: found non-foreign-function-safe member in struct marked #[repr(C)]: found struct without foreign-function-safe representation annotation in foreign module, consider adding a #[repr(C)] attribute to the type, #[warn(improper_ctypes)] on by default --> <anon>:5:19 5 |> pub fn f(foo: *mut Foo); |> ^^^^^^^^ This comes up in bindings generated from C code that contains unions (the __BindgenUnionField type).