From 6351bfd182267133409c5174decdff2071f90454 Mon Sep 17 00:00:00 2001
From: Yuki Okushi <huyuumi.dev@gmail.com>
Date: Sun, 16 Feb 2020 02:53:58 +0900
Subject: [PATCH] Add test for issue-39618

---
 src/test/ui/specialization/issue-39618.rs | 24 +++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 src/test/ui/specialization/issue-39618.rs

diff --git a/src/test/ui/specialization/issue-39618.rs b/src/test/ui/specialization/issue-39618.rs
new file mode 100644
index 00000000000..78894a56997
--- /dev/null
+++ b/src/test/ui/specialization/issue-39618.rs
@@ -0,0 +1,24 @@
+// Regression test for #39618, shouldn't crash.
+// check-pass
+
+#![feature(specialization)]
+
+trait Foo {
+    fn foo(&self);
+}
+
+trait Bar {
+    fn bar(&self);
+}
+
+impl<T> Bar for T where T: Foo {
+    fn bar(&self) {}
+}
+
+impl<T> Foo for T where T: Bar {
+    fn foo(&self) {}
+}
+
+impl Foo for u64 {}
+
+fn main() {}