1 files changed, 9 insertions, 0 deletions
diff --git a/tests/ui/type-alias-impl-trait/auxiliary/coherence_cross_crate_trait_decl.rs b/tests/ui/type-alias-impl-trait/auxiliary/coherence_cross_crate_trait_decl.rs
new file mode 100644
index 000000000..712ed5543
--- /dev/null
+++ b/tests/ui/type-alias-impl-trait/auxiliary/coherence_cross_crate_trait_decl.rs
@@ -0,0 +1,9 @@
+pub trait SomeTrait {}
+
+impl SomeTrait for () {}
+
+// Adding this `impl` would cause errors in this crate's dependent,
+// so it would be a breaking change. We explicitly don't add this impl,
+// as the dependent crate already assumes this impl exists and thus already
+// does not compile.
+//impl SomeTrait for i32 {}