1 files changed, 24 insertions, 0 deletions

diff --git a/tests/ui/issues/issue-58375-monomorphize-default-impls.rs b/tests/ui/issues/issue-58375-monomorphize-default-impls.rs
new file mode 100644
index 000000000..6da6f398d
--- /dev/null
+++ b/tests/ui/issues/issue-58375-monomorphize-default-impls.rs
@@ -0,0 +1,24 @@
+// Make sure that the mono-item collector does not crash when trying to
+// instantiate a default impl for DecodeUtf16<<u8 as A>::Item>
+// See https://github.com/rust-lang/rust/issues/58375
+
+// build-pass
+// compile-flags:-C link-dead-code
+
+#![crate_type = "rlib"]
+
+pub struct DecodeUtf16<I>(I);
+
+pub trait Arbitrary {
+    fn arbitrary() {}
+}
+
+pub trait A {
+    type Item;
+}
+
+impl A for u8 {
+    type Item = char;
+}
+
+impl Arbitrary for DecodeUtf16<<u8 as A>::Item> {}