1 files changed, 28 insertions, 0 deletions

diff --git a/tests/ui/issues/issue-34796.rs b/tests/ui/issues/issue-34796.rs
new file mode 100644
index 000000000..88d5c50a2
--- /dev/null
+++ b/tests/ui/issues/issue-34796.rs
@@ -0,0 +1,28 @@
+// run-pass
+#![allow(dead_code)]
+// This test case exposes conditions where the encoding of a trait object type
+// with projection predicates would differ between this crate and the upstream
+// crate, because the predicates were encoded in different order within each
+// crate. This led to different symbol hashes of functions using these type,
+// which in turn led to linker errors because the two crates would not agree on
+// the symbol name.
+// The fix was to make the order in which predicates get encoded stable.
+
+// aux-build:issue-34796-aux.rs
+extern crate issue_34796_aux;
+
+fn mk<T>() -> T { loop {} }
+
+struct Data<T, E> {
+    data: T,
+    error: E,
+}
+
+fn main() {
+    issue_34796_aux::bar(|()| {
+        Data::<(), std::io::Error> {
+            data: mk(),
+            error: mk(),
+        }
+    })
+}