Use explicit pointer casting

This commit replaces calls to `pointer::cast` with explicit casting via `as *mut SomeType`. This reduces the likelihood of our codegen generating unsound code that casts a pointer to the wrong type.
chinedufn · Apr 29, 2024 · b4ba1a7 · b4ba1a7
1 parent 9d02d8f
commit b4ba1a7
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Showing 2 changed files with 6 additions and 4 deletions.
diff --git a/crates/swift-bridge-ir/src/bridged_type/bridged_opaque_type.rs b/crates/swift-bridge-ir/src/bridged_type/bridged_opaque_type.rs
@@ -322,9 +322,11 @@ impl BridgeableType for OpaqueForeignType {
                     }
                 }
                 HostLang::Swift => {
+                    let ty = &self.ty;
+
                     quote! {
                         if let Some(val) = #expression {
-                            val.0.cast()
+                            val.0 as *mut super::#ty
                         } else {
                             std::ptr::null_mut()
                         }
@@ -517,7 +519,7 @@ impl BridgeableType for OpaqueForeignType {
                             if val.is_null() {
                                 None
                             } else {
-                                Some(#ty(val.cast()))
+                                Some(#ty(val as *mut std::ffi::c_void))
                             }
                         }
                     }

diff --git a/crates/swift-bridge-ir/src/codegen/codegen_tests/option_codegen_tests.rs b/crates/swift-bridge-ir/src/codegen/codegen_tests/option_codegen_tests.rs
@@ -676,7 +676,7 @@ mod extern_rust_fn_return_option_opaque_swift_type {
                 #[export_name = "__swift_bridge__$some_function"]
                 pub extern "C" fn __swift_bridge__some_function() -> *mut super::SomeSwiftType {
                     if let Some(val) = super::some_function() {
-                        val.0.cast()
+                        val.0 as *mut super::SomeSwiftType
                     } else {
                         std::ptr::null_mut()
                     }
@@ -929,7 +929,7 @@ mod extern_rust_fn_with_option_opaque_swift_type_arg {
                         if val.is_null() {
                             None
                         } else {
-                            Some(SomeSwiftType(val.cast()))
+                            Some(SomeSwiftType(val as *mut std::ffi::c_void))
                         }
                     })
                 }