Merge pull request #25 from JohnTitor/fix-unaligned-references

JohnTitor · May 23, 2021 · aab0ed6 · aab0ed6
2 parents 64fc427 + cdd2003
commit aab0ed6
Show file tree

Hide file tree

Showing 6 changed files with 21 additions and 18 deletions.
diff --git a/src/lib.rs b/src/lib.rs
@@ -1276,11 +1276,13 @@ impl<'a> Generator<'a> {
                     fn __test_fsize_{ty}_{field}() -> u64;
                 }}
                 unsafe {{
-                    let foo = 0 as *mut {ty};
+                    let zeroed_ty = std::mem::zeroed::<{ty}>();
+                    let ty_ptr = std::ptr::addr_of!((zeroed_ty).{field});
+                    let val = ty_ptr.read_unaligned();
                     same(offset_of!({ty}, {field}),
                          __test_offset_{ty}_{field}(),
                          "field offset {field} of {ty}");
-                    same(mem::size_of_val(&(*foo).{field}) as u64,
+                    same(mem::size_of_val(&val) as u64,
                          __test_fsize_{ty}_{field}(),
                          "field size {field} of {ty}");
                 }}
@@ -1325,10 +1327,13 @@ impl<'a> Generator<'a> {
                                                       -> *mut u8;
                 }}
                 unsafe {{
-                    let foo = 0 as *mut {ty};
-                    same(&(*foo).{field} as *const _ as *mut _,
-                         __test_field_type_{ty}_{field}(foo),
+                    let mut zeroed_ty = mem::zeroed::<{ty}>();
+                    let ty_ptr_mut = std::ptr::addr_of_mut!(zeroed_ty);
+                    let field_ptr = std::ptr::addr_of!(zeroed_ty.{field});
+                    same(field_ptr as *mut _,
+                         __test_field_type_{ty}_{field}(ty_ptr_mut),
                          "field type {field} of {ty}");
+                    mem::forget(zeroed_ty);
                 }}
             "#,
                 ty = ty,
@@ -1850,9 +1855,11 @@ impl<'a> Generator<'a> {
                     self.rust,
                     r#"
                     unsafe {{
-                      let size = mem::size_of_val(&(*foo).{field});
-                      let off = offset_of!({ty}, {field}) as usize;
-                      v.push((off, size));
+                        let ty_ptr = std::ptr::addr_of!((*foo).{field});
+                        let val = ty_ptr.read_unaligned();
+                        let size = mem::size_of_val(&val);
+                        let off = offset_of!({ty}, {field}) as usize;
+                        v.push((off, size));
                     }}
                     "#,
                     ty = rust,

diff --git a/testcrate/src/bin/t1.rs b/testcrate/src/bin/t1.rs
@@ -1,6 +1,5 @@
 #![cfg(not(test))]
 #![deny(warnings)]
-#![allow(unaligned_references)]
 
 use libc::*;
 use testcrate::t1::*;

diff --git a/testcrate/src/bin/t1_cxx.rs b/testcrate/src/bin/t1_cxx.rs
@@ -1,6 +1,5 @@
 #![cfg(not(test))]
 #![deny(warnings)]
-#![allow(unaligned_references)]
 
 use libc::*;
 use testcrate::t1::*;

diff --git a/testcrate/src/bin/t2.rs b/testcrate/src/bin/t2.rs
@@ -1,6 +1,5 @@
 #![cfg(not(test))]
 #![deny(warnings)]
-#![allow(unaligned_references)]
 
 use testcrate::t2::*;
 

diff --git a/testcrate/src/bin/t2_cxx.rs b/testcrate/src/bin/t2_cxx.rs
@@ -1,6 +1,5 @@
 #![cfg(not(test))]
 #![deny(warnings)]
-#![allow(unaligned_references)]
 
 use testcrate::t2::*;
 

diff --git a/testcrate/tests/all.rs b/testcrate/tests/all.rs
@@ -15,22 +15,22 @@ fn cmd(name: &str) -> Command {
 #[test]
 fn t1() {
     let (o, status) = output(&mut cmd("t1"));
-    assert!(status.success(), o);
-    assert!(!o.contains("bad "), o);
+    assert!(status.success(), "{}", o);
+    assert!(!o.contains("bad "), "{}", o);
     eprintln!("o: {}", o);
 }
 
 #[test]
 fn t1_cxx() {
     let (o, status) = output(&mut cmd("t1_cxx"));
-    assert!(status.success(), o);
-    assert!(!o.contains("bad "), o);
+    assert!(status.success(), "{}", o);
+    assert!(!o.contains("bad "), "{}", o);
 }
 
 #[test]
 fn t2() {
     let (o, status) = output(&mut cmd("t2"));
-    assert!(!status.success(), o);
+    assert!(!status.success(), "{}", o);
     let errors = [
         "bad T2Foo signed",
         "bad T2TypedefFoo signed",
@@ -74,7 +74,7 @@ fn t2() {
 #[test]
 fn t2_cxx() {
     let (o, status) = output(&mut cmd("t2_cxx"));
-    assert!(!status.success(), o);
+    assert!(!status.success(), "{}", o);
     let errors = [
         "bad T2Foo signed",
         "bad T2TypedefFoo signed",