1 files changed, 18 insertions, 0 deletions

diff --git a/src/test/ui/issues/issue-21600.rs b/src/test/ui/issues/issue-21600.rs
new file mode 100644
index 000000000..2e22e5e6f
--- /dev/null
+++ b/src/test/ui/issues/issue-21600.rs
@@ -0,0 +1,18 @@
+fn call_it<F>(f: F) where F: Fn() { f(); }
+
+struct A;
+
+impl A {
+    fn gen(&self) {}
+    fn gen_mut(&mut self) {}
+}
+
+fn main() {
+    let mut x = A;
+    call_it(|| {
+        call_it(|| x.gen());
+        call_it(|| x.gen_mut());
+        //~^ ERROR cannot borrow `x` as mutable, as it is a captured variable in a `Fn` closure
+        //~| ERROR cannot borrow `x` as mutable, as it is a captured variable in a `Fn` closure
+    });
+}