1 files changed, 21 insertions, 0 deletions
diff --git a/src/test/ui/typeck/project-cache-issue-37154.rs b/src/test/ui/typeck/project-cache-issue-37154.rs
new file mode 100644
index 000000000..b10239c22
--- /dev/null
+++ b/src/test/ui/typeck/project-cache-issue-37154.rs
@@ -0,0 +1,21 @@
+// run-pass
+
+#![allow(dead_code)]
+// Regression test for #37154: the problem here was that the cache
+// results in a false error because it was caching placeholder results
+// even after those placeholder regions had been popped.
+
+trait Foo {
+    fn method(&self) {}
+}
+
+struct Wrapper<T>(T);
+
+impl<T> Foo for Wrapper<T> where for<'a> &'a T: IntoIterator<Item=&'a ()> {}
+
+fn f(x: Wrapper<Vec<()>>) {
+    x.method(); // This works.
+    x.method(); // error: no method named `method`
+}
+
+fn main() { }