rust: qdev: const_refs_to_static

Now that const_refs_static can be assumed, convert the members of
the DeviceImpl trait from functions to constants.  This lets the
compiler know that they have a 'static lifetime, and removes the
need for the weird "Box::leak()".

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250908105005.2119297-10-pbonzini@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

2 files changed, 23 insertions, 29 deletions

diff --git a/rust/qemu-api-macros/src/lib.rs b/rust/qemu-api-macros/src/lib.rs
index 97b2c214b6..a65a7ce2fe 100644
--- a/rust/qemu-api-macros/src/lib.rs
+++ b/rust/qemu-api-macros/src/lib.rs
@@ -289,11 +289,9 @@ fn derive_device_or_error(input: DeriveInput) -> Result<proc_macro2::TokenStream
 
     Ok(quote_spanned! {input.span() =>
         unsafe impl ::qemu_api::qdev::DevicePropertiesImpl for #name {
-            fn properties() -> &'static [::qemu_api::bindings::Property] {
-                static PROPERTIES: &[::qemu_api::bindings::Property] = &[#(#properties_expanded),*];
-
-                PROPERTIES
-            }
+            const PROPERTIES: &'static [::qemu_api::bindings::Property] = &[
+                #(#properties_expanded),*
+            ];
         }
     })
 }
diff --git a/rust/qemu-api-macros/src/tests.rs b/rust/qemu-api-macros/src/tests.rs
index aafffcdce9..0e5a572890 100644
--- a/rust/qemu-api-macros/src/tests.rs
+++ b/rust/qemu-api-macros/src/tests.rs
@@ -101,18 +101,16 @@ fn test_derive_device() {
         },
         quote! {
             unsafe impl ::qemu_api::qdev::DevicePropertiesImpl for DummyState {
-                fn properties() -> &'static [::qemu_api::bindings::Property] {
-                    static PROPERTIES: &[::qemu_api::bindings::Property] =
-                        &[::qemu_api::bindings::Property {
-                            name: ::std::ffi::CStr::as_ptr(c"migrate_clock"),
-                            info: <bool as ::qemu_api::qdev::QDevProp>::VALUE,
-                            offset: ::core::mem::offset_of!(DummyState, migrate_clock) as isize,
-                            set_default: true,
-                            defval: ::qemu_api::bindings::Property__bindgen_ty_1 { u: true as u64 },
-                            ..::qemu_api::zeroable::Zeroable::ZERO
-                        }];
-                    PROPERTIES
-                }
+                const PROPERTIES: &'static [::qemu_api::bindings::Property] = &[
+                    ::qemu_api::bindings::Property {
+                        name: ::std::ffi::CStr::as_ptr(c"migrate_clock"),
+                        info: <bool as ::qemu_api::qdev::QDevProp>::VALUE,
+                        offset: ::core::mem::offset_of!(DummyState, migrate_clock) as isize,
+                        set_default: true,
+                        defval: ::qemu_api::bindings::Property__bindgen_ty_1 { u: true as u64 },
+                        ..::qemu_api::zeroable::Zeroable::ZERO
+                    }
+                ];
             }
         }
     );
@@ -130,18 +128,16 @@ fn test_derive_device() {
         },
         quote! {
             unsafe impl ::qemu_api::qdev::DevicePropertiesImpl for DummyState {
-                fn properties() -> &'static [::qemu_api::bindings::Property] {
-                    static PROPERTIES: &[::qemu_api::bindings::Property] =
-                        &[::qemu_api::bindings::Property {
-                            name: ::std::ffi::CStr::as_ptr(c"migrate-clk"),
-                            info: <bool as ::qemu_api::qdev::QDevProp>::VALUE,
-                            offset: ::core::mem::offset_of!(DummyState, migrate_clock) as isize,
-                            set_default: true,
-                            defval: ::qemu_api::bindings::Property__bindgen_ty_1 { u: true as u64 },
-                            ..::qemu_api::zeroable::Zeroable::ZERO
-                        }];
-                    PROPERTIES
-                }
+                const PROPERTIES: &'static [::qemu_api::bindings::Property] = &[
+                    ::qemu_api::bindings::Property {
+                        name: ::std::ffi::CStr::as_ptr(c"migrate-clk"),
+                        info: <bool as ::qemu_api::qdev::QDevProp>::VALUE,
+                        offset: ::core::mem::offset_of!(DummyState, migrate_clock) as isize,
+                        set_default: true,
+                        defval: ::qemu_api::bindings::Property__bindgen_ty_1 { u: true as u64 },
+                        ..::qemu_api::zeroable::Zeroable::ZERO
+                    }
+                ];
             }
         }
     );