Re: [PATCH 00/10] qom: Constify class_data

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 10/2/25 13:30, Paolo Bonzini wrote:
> On 2/10/25 11:25, Philippe Mathieu-Daudé wrote:
>> Following Richard's suggestion [*], make QOM class data *const*.
>>
>> Note, rust code not modified...
> 
> Untested but it should be something like
> 
> diff --git a/rust/qemu-api/src/qom.rs b/rust/qemu-api/src/qom.rs
> index f36be2831eb..8603f7cc657 100644
> --- a/rust/qemu-api/src/qom.rs
> +++ b/rust/qemu-api/src/qom.rs
> @@ -180,7 +180,7 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> 
> Result<(), fmt::Error> {
> 
>   unsafe extern "C" fn rust_class_init<T: ObjectType + 
> ClassInitImpl<T::Class>>(
>       klass: *mut ObjectClass,
> -    _data: *mut c_void,
> +    _data: *const c_void,
>   ) {
>       let mut klass = NonNull::new(klass)
>           .unwrap()
> @@ -523,7 +523,7 @@ pub trait ObjectImpl: ObjectType + 
> ClassInitImpl<Self::Class> {
>       /// the effects of copying the contents of the parent's class struct
>       /// to the descendants.
>       const CLASS_BASE_INIT: Option<
> -        unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut c_void),
> +        unsafe extern "C" fn(klass: *mut ObjectClass, data: *const 
> c_void),
>       > = None;
> 
>       const TYPE_INFO: TypeInfo = TypeInfo {
> @@ -544,7 +544,7 @@ pub trait ObjectImpl: ObjectType + 
> ClassInitImpl<Self::Class> {
>           class_size: core::mem::size_of::<Self::Class>(),
>           class_init: Some(rust_class_init::<Self>),
>           class_base_init: Self::CLASS_BASE_INIT,
> -        class_data: core::ptr::null_mut(),
> +        class_data: core::ptr::null(),
>           interfaces: core::ptr::null_mut(),
>       };
> 
> 
> to be split across patches 8-10.

Thanks!