1 files changed, 18 insertions, 0 deletions

diff --git a/src/test/ui/issues/issue-7013.stderr b/src/test/ui/issues/issue-7013.stderr
new file mode 100644
index 000000000..f6cb1cbdc
--- /dev/null
+++ b/src/test/ui/issues/issue-7013.stderr
@@ -0,0 +1,18 @@
+error[E0277]: `Rc<RefCell<A>>` cannot be sent between threads safely
+  --> $DIR/issue-7013.rs:26:19
+   |
+LL |     let a = A {v: box B{v: None} as Box<dyn Foo + Send>};
+   |                   ^^^^^^^^^^^^^^ `Rc<RefCell<A>>` cannot be sent between threads safely
+   |
+   = help: within `B`, the trait `Send` is not implemented for `Rc<RefCell<A>>`
+   = note: required because it appears within the type `Option<Rc<RefCell<A>>>`
+note: required because it appears within the type `B`
+  --> $DIR/issue-7013.rs:10:8
+   |
+LL | struct B {
+   |        ^
+   = note: required for the cast from `B` to the object type `dyn Foo + Send`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.