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diff --git a/tests/ui/derives/deriving-with-repr-packed-2.rs b/tests/ui/derives/deriving-with-repr-packed-2.rs
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+// Check that deriving certain builtin traits on certain packed structs cause
+// errors. To avoid potentially misaligned references, field copies must be
+// used, which involves adding `T: Copy` bounds.
+
+#[derive(Copy, Clone, Default, PartialEq, Eq)]
+#[repr(packed)]
+pub struct Foo<T>(T, T, T);
+
+struct NonCopy;
+
+fn main() {
+ // This one is fine because `u32` impls `Copy`.
+ let x: Foo<u32> = Foo(1, 2, 3);
+ _ = x.clone();
+
+ // This one is an error because `NonCopy` doesn't impl `Copy`.
+ let x: Foo<NonCopy> = Foo(NonCopy, NonCopy, NonCopy);
+ _ = x.clone();
+ //~^ ERROR the method `clone` exists for struct `Foo<NonCopy>`, but its trait bounds were not satisfied
+}