1 files changed, 50 insertions, 0 deletions
diff --git a/tests/ui/traits/vtable/multiple-auto.rs b/tests/ui/traits/vtable/multiple-auto.rs
new file mode 100644
index 00000000000..87ee865868b
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+++ b/tests/ui/traits/vtable/multiple-auto.rs
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+// Related to <https://github.com/rust-lang/rust/issues/113840>
+//
+// This test makes sure that multiple auto traits can reuse the
+// same pointer for upcasting (e.g. `Send`/`Sync`)
+
+#![crate_type = "lib"]
+#![feature(rustc_attrs, auto_traits)]
+
+// Markers
+auto trait M0 {}
+auto trait M1 {}
+auto trait M2 {}
+
+// Just a trait with a method
+trait T {
+    fn method(&self) {}
+}
+
+trait A: M0 + M1 + M2 + T {}
+
+trait B: M0 + M1 + T + M2 {}
+
+trait C: M0 + T + M1 + M2 {}
+
+trait D: T + M0 + M1 + M2 {}
+
+struct S;
+
+impl M0 for S {}
+impl M1 for S {}
+impl M2 for S {}
+impl T for S {}
+
+#[rustc_dump_vtable]
+impl A for S {}
+//~^ ERROR vtable entries
+
+#[rustc_dump_vtable]
+impl B for S {}
+//~^ ERROR vtable entries
+
+#[rustc_dump_vtable]
+impl C for S {}
+//~^ ERROR vtable entries
+
+#[rustc_dump_vtable]
+impl D for S {}
+//~^ ERROR vtable entries
+
+fn main() {}