native-lib: bump libffi

Cargo.toml

@@ -39,7 +39,7 @@ features = ['unprefixed_malloc_on_supported_platforms']
 [target.'cfg(unix)'.dependencies]
 libc = "0.2"
 # native-lib dependencies
-libffi = { version = "4.1.1", optional = true }
+libffi = { version = "5.0.0", optional = true }
 libloading = { version = "0.8", optional = true }
 serde = { version = "1.0.219", features = ["derive"], optional = true }
 

src/shims/native_lib/ffi.rs

@@ -9,11 +9,9 @@ use libffi::middle::{Arg as ArgPtr, Cif, Type as FfiType};
 ///
 /// The safety invariants of the foreign function being called must be upheld (if any).
 pub unsafe fn call<R: libffi::high::CType>(fun: CodePtr, args: &mut [OwnedArg]) -> R {
-    let arg_ptrs: Vec<_> = args.iter().map(|arg| arg.ptr()).collect();
     let cif = Cif::new(args.iter_mut().map(|arg| arg.ty.take().unwrap()), R::reify().into_middle());
-    // SAFETY: Caller upholds that the function is safe to call, and since we
-    // were passed a slice reference we know the `OwnedArg`s won't have been
-    // dropped by this point.
+    let arg_ptrs: Vec<_> = args.iter().map(|arg| ArgPtr::new(&*arg.bytes)).collect();
+    // SAFETY: Caller upholds that the function is safe to call.
     unsafe { cif.call(fun, &arg_ptrs) }
 }
 
@@ -31,16 +29,4 @@ impl OwnedArg {
     pub fn new(ty: FfiType, bytes: Box<[u8]>) -> Self {
         Self { ty: Some(ty), bytes }
     }
-
-    /// Creates a libffi argument pointer pointing to this argument's bytes.
-    /// NB: Since `libffi::middle::Arg` ignores the lifetime of the reference
-    /// it's derived from, it is up to the caller to ensure the `OwnedArg` is
-    /// not dropped before unsafely calling `libffi::middle::Cif::call()`!
-    fn ptr(&self) -> ArgPtr {
-        // FIXME: Using `&self.bytes[0]` to reference the whole array is
-        // definitely unsound under SB, but we're waiting on
-        // https://github.com/libffi-rs/libffi-rs/commit/112a37b3b6ffb35bd75241fbcc580de40ba74a73
-        // to land in a release so that we don't need to do this.
-        ArgPtr::new(&self.bytes[0])
-    }
 }