1 files changed, 14 insertions, 0 deletions

diff --git a/tests/ui/issues/issue-39984.rs b/tests/ui/issues/issue-39984.rs
new file mode 100644
index 000000000..1c9ae26ca
--- /dev/null
+++ b/tests/ui/issues/issue-39984.rs
@@ -0,0 +1,14 @@
+// check-pass
+#![allow(dead_code)]
+#![allow(unreachable_code)]
+// Regression test for issue #39984.
+//
+// The key here is that the error type of the `Ok` call ought to be
+// constrained to `String`, even though it is dead-code.
+
+fn main() {}
+
+fn t() -> Result<(), String> {
+    return Err("".into());
+    Ok(())
+}