Fix size/align of ucontext_t on aarch64-apple-darwin

alexcrichton · alexcrichton · commit 283ef4b2407a · 2023-08-02T01:08:01.000-07:00
This commit effectively reverts #2817. Currently `ucontext_t` has both the wrong size and the wrong alignment for aarch64-apple-darwin which causes problems for users referencing the structure [1]. The issue linked from #2817 claimed that it fixed #2812 but that's still an issue where FFI warnings are still emitted for usage of `ucontext_t` due to its transitive usage of `u128`. I'm not sure how to fix #2812 myself, but given that #2817 doesn't appear to solve its original intent and additionally the size/align are currently wrong this commit reverts in the meantime. [1]: bytecodealliance/wasmtime#6785 (comment)
diff --git a/src/unix/bsd/apple/b64/aarch64/align.rs b/src/unix/bsd/apple/b64/aarch64/align.rs
@@ -15,7 +15,6 @@ s! {
         pub uc_link: *mut ::ucontext_t,
         pub uc_mcsize: usize,
         pub uc_mcontext: mcontext_t,
-        __mcontext_data: __darwin_mcontext64,
     }
 
     pub struct __darwin_mcontext64 {

Original file line number	Diff line number	Diff line change
`@@ -15,7 +15,6 @@ s! {`
`15`	`15`	`pub uc_link: *mut ::ucontext_t,`
`16`	`16`	`pub uc_mcsize: usize,`
`17`	`17`	`pub uc_mcontext: mcontext_t,`
`18`		`- __mcontext_data: __darwin_mcontext64,`
`19`	`18`	`}`
`20`	`19`
`21`	`20`	`pub struct __darwin_mcontext64 {`