1 files changed, 15 insertions, 0 deletions
diff --git a/src/test/ui/traits/mutual-recursion-issue-75860.rs b/src/test/ui/traits/mutual-recursion-issue-75860.rs
new file mode 100644
index 000000000..d7d7307b4
--- /dev/null
+++ b/src/test/ui/traits/mutual-recursion-issue-75860.rs
@@ -0,0 +1,15 @@
+pub fn iso<A, B, F1, F2>(a: F1, b: F2) -> (Box<dyn Fn(A) -> B>, Box<dyn Fn(B) -> A>)
+    where
+        F1: (Fn(A) -> B) + 'static,
+        F2: (Fn(B) -> A) + 'static,
+{
+    (Box::new(a), Box::new(b))
+}
+pub fn iso_un_option<A, B>() -> (Box<dyn Fn(A) -> B>, Box<dyn Fn(B) -> A>) {
+   let left = |o_a: Option<_>| o_a.unwrap();
+    let right = |o_b: Option<_>| o_b.unwrap();
+    iso(left, right)
+    //~^ ERROR overflow
+}
+
+fn main() {}