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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=pbonzini@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.644, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 5/2/25 13:01, Manos Pitsidianakis wrote: > On Fri, 02 May 2025 13:23, Paolo Bonzini wrote: >> Signed-off-by: Paolo Bonzini >> --- >> docs/devel/rust.rst | 4 -- >> rust/hw/timer/hpet/src/fw_cfg.rs | 6 +- >> rust/qemu-api/src/zeroable.rs | 104 +++++-------------------------- >> 3 files changed, 18 insertions(+), 96 deletions(-) > > Reviewed-by: Manos Pitsidianakis > > BTW There's this TODO in qom.rs, ObjectImpl trait > >> /// `&mut T`. TODO: add a bound of >> //[`Zeroable`](crate::zeroable::Zeroable) >> /// to T; this is more easily done once Zeroable does not require a manual >> /// implementation (Rust 1.75.0). >> const CLASS_INIT: fn(&mut Self::Class); Yes, good point. When I wrote the TODO, my idea here was to have some kind of #[derive(Zeroable)] macro so that the compiler can "confirm" the safety of implementing Zeroable by hand. However, most of the time the class will be just a C-defined class (DeviceClass or SysBusDeviceClass), and then it's not even possible to add the derive attribute to the declaration. So adding the bound to ObjectType::Class is feasible now that one can just add unsafe impl Zeroable for bindings::ObjectClass {} unsafe impl Zeroable for bindings::DeviceClass {} unsafe impl Zeroable for bindings::SysBusDeviceClass {} unsafe impl Zeroable for bindings::ResettableClass {} etc.; in fact it was already possible when Zhao added the impl_zeroed! macro in commit aaf3778baaa ("rust/zeroable: Implement Zeroable with const_zero macro", 2025-01-28). Paolo