diff --git a/src/test/run-pass/alt-with-ret-arm.rs b/src/test/run-pass/alt-with-ret-arm.rs
new file mode 100644
index 000000000000..20fe17d4847b
--- /dev/null
+++ b/src/test/run-pass/alt-with-ret-arm.rs
@@ -0,0 +1,11 @@
+fn main() {
+    // sometimes we have had trouble finding
+    // the right type for f, as we unified
+    // bot and u32 here
+    let f = alt uint::from_str("1234") {
+        none { ret () }
+        some(num) { num as u32 }
+    };
+    assert f == 1234u32;
+    log(error, f)
+}