1 files changed, 36 insertions, 0 deletions
diff --git a/tests/ui/deriving/deriving-with-repr-packed.rs b/tests/ui/deriving/deriving-with-repr-packed.rs
new file mode 100644
index 000000000..8ce444be1
--- /dev/null
+++ b/tests/ui/deriving/deriving-with-repr-packed.rs
@@ -0,0 +1,36 @@
+// run-pass
+// check that derive on a packed struct does not call field
+// methods with a misaligned field.
+
+use std::mem;
+
+#[derive(Copy, Clone)]
+struct Aligned(usize);
+
+#[inline(never)]
+fn check_align(ptr: *const Aligned) {
+    assert_eq!(ptr as usize % mem::align_of::<Aligned>(),
+               0);
+}
+
+impl PartialEq for Aligned {
+    fn eq(&self, other: &Self) -> bool {
+        check_align(self);
+        check_align(other);
+        self.0 == other.0
+    }
+}
+
+#[repr(packed)]
+#[derive(Copy, Clone, PartialEq)]
+struct Packed(Aligned, Aligned);
+
+#[derive(PartialEq)]
+#[repr(C)]
+struct Dealigned<T>(u8, T);
+
+fn main() {
+    let d1 = Dealigned(0, Packed(Aligned(1), Aligned(2)));
+    let ck = d1 == d1;
+    assert!(ck);
+}