From 7dd1b6a22fc7c98cc3e3daeaae3a51bc184fee34 Mon Sep 17 00:00:00 2001
From: kadmin <julianknodt@gmail.com>
Date: Tue, 4 Aug 2020 23:07:04 +0000
Subject: [PATCH] Add regression test

---
 .../ui/const-generics/issues/issue-64494.rs   | 19 +++++++++++++++++++
 .../const-generics/issues/issue-64494.stderr  | 18 ++++++++++++++++++
 2 files changed, 37 insertions(+)
 create mode 100644 src/test/ui/const-generics/issues/issue-64494.rs
 create mode 100644 src/test/ui/const-generics/issues/issue-64494.stderr

diff --git a/src/test/ui/const-generics/issues/issue-64494.rs b/src/test/ui/const-generics/issues/issue-64494.rs
new file mode 100644
index 0000000000000..4c755530b9979
--- /dev/null
+++ b/src/test/ui/const-generics/issues/issue-64494.rs
@@ -0,0 +1,19 @@
+#![feature(const_generics)]
+#![allow(incomplete_features)]
+
+trait Foo {
+    const VAL: usize;
+}
+
+trait MyTrait {}
+
+trait True {}
+struct Is<const T: bool>;
+impl True for Is<{true}> {}
+
+impl<T: Foo> MyTrait for T where Is<{T::VAL == 5}>: True {}
+//~^ ERROR constant expression depends on a generic parameter
+impl<T: Foo> MyTrait for T where Is<{T::VAL == 6}>: True {}
+//~^ ERROR constant expression depends on a generic parameter
+
+fn main() {}
diff --git a/src/test/ui/const-generics/issues/issue-64494.stderr b/src/test/ui/const-generics/issues/issue-64494.stderr
new file mode 100644
index 0000000000000..30dca16964317
--- /dev/null
+++ b/src/test/ui/const-generics/issues/issue-64494.stderr
@@ -0,0 +1,18 @@
+error: constant expression depends on a generic parameter
+  --> $DIR/issue-64494.rs:14:53
+   |
+LL | impl<T: Foo> MyTrait for T where Is<{T::VAL == 5}>: True {}
+   |                                                     ^^^^
+   |
+   = note: this may fail depending on what value the parameter takes
+
+error: constant expression depends on a generic parameter
+  --> $DIR/issue-64494.rs:16:53
+   |
+LL | impl<T: Foo> MyTrait for T where Is<{T::VAL == 6}>: True {}
+   |                                                     ^^^^
+   |
+   = note: this may fail depending on what value the parameter takes
+
+error: aborting due to 2 previous errors
+