[PATCH 07/13] rust: modernize #[derive(Object)] for ELF platforms

Paolo Bonzini posted 13 patches 4 days, 8 hours ago
There is a newer version of this series
[PATCH 07/13] rust: modernize #[derive(Object)] for ELF platforms
Posted by Paolo Bonzini 4 days, 8 hours ago
Some newer ABI implementations do not provide .ctors; and while
some linkers rewrite .ctors into .init_array, not all of them do.
Use the newer .init_array ABI, which works more reliably, and
apply it to all non-Apple, non-Windows platforms.

This is similar to how the ctor crate operates; without this change,
"#[derive(Object)]" does not work on Fedora 41.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 rust/qemu-api-macros/src/lib.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/rust/qemu-api-macros/src/lib.rs b/rust/qemu-api-macros/src/lib.rs
index 59aba592d9a..be8874caea1 100644
--- a/rust/qemu-api-macros/src/lib.rs
+++ b/rust/qemu-api-macros/src/lib.rs
@@ -16,8 +16,8 @@ pub fn derive_object(input: TokenStream) -> TokenStream {
     let expanded = quote! {
         #[allow(non_upper_case_globals)]
         #[used]
-        #[cfg_attr(target_os = "linux", link_section = ".ctors")]
-        #[cfg_attr(target_os = "macos", link_section = "__DATA,__mod_init_func")]
+        #[cfg_attr(not(any(target_vendor = "apple", target_os = "windows")), link_section = ".init_array")]
+        #[cfg_attr(target_vendor = "apple", link_section = "__DATA,__mod_init_func")]
         #[cfg_attr(target_os = "windows", link_section = ".CRT$XCU")]
         pub static #module_static: extern "C" fn() = {
             extern "C" fn __register() {
-- 
2.46.2
Re: [PATCH 07/13] rust: modernize #[derive(Object)] for ELF platforms
Posted by Junjie Mao 1 day, 13 hours ago
Paolo Bonzini <pbonzini@redhat.com> writes:

> Some newer ABI implementations do not provide .ctors; and while
> some linkers rewrite .ctors into .init_array, not all of them do.
> Use the newer .init_array ABI, which works more reliably, and
> apply it to all non-Apple, non-Windows platforms.
>
> This is similar to how the ctor crate operates; without this change,
> "#[derive(Object)]" does not work on Fedora 41.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Junjie Mao <junjie.mao@hotmail.com>

--
Best Regards
Junjie Mao