1 files changed, 14 insertions, 0 deletions

diff --git a/src/test/ui/issues/issue-43355.stderr b/src/test/ui/issues/issue-43355.stderr
new file mode 100644
index 000000000..531130fec
--- /dev/null
+++ b/src/test/ui/issues/issue-43355.stderr
@@ -0,0 +1,14 @@
+error[E0119]: conflicting implementations of trait `Trait1<std::boxed::Box<_>>` for type `A`
+  --> $DIR/issue-43355.rs:13:1
+   |
+LL | impl<X, T> Trait1<X> for T where T: Trait2<X> {
+   | -------------------------- first implementation here
+...
+LL | impl<X> Trait1<Box<X>> for A {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `A`
+   |
+   = note: downstream crates may implement trait `Trait2<std::boxed::Box<_>>` for type `A`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0119`.