project: add a recursion limit to "tail-recursive" projections

Fixes #21946
Fixes #23992
Fixes #25945

2 files changed, 50 insertions, 0 deletions

diff --git a/src/test/compile-fail/issue-21946.rs b/src/test/compile-fail/issue-21946.rs
new file mode 100644
index 00000000000..0d652be5c26
--- /dev/null
+++ b/src/test/compile-fail/issue-21946.rs
@@ -0,0 +1,22 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+trait Foo {
+    type A;
+}
+
+struct FooStruct;
+
+impl Foo for FooStruct {
+//~^ ERROR overflow evaluating the requirement `<FooStruct as Foo>::A`
+    type A = <FooStruct as Foo>::A;
+}
+
+fn main() {}
diff --git a/src/test/run-pass/issue-23992.rs b/src/test/run-pass/issue-23992.rs
new file mode 100644
index 00000000000..d1ee4208b78
--- /dev/null
+++ b/src/test/run-pass/issue-23992.rs
@@ -0,0 +1,28 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub struct Outer<T: Trait>(T);
+pub struct Inner<'a> { value: &'a bool }
+
+pub trait Trait {
+    type Error;
+    fn ready(self) -> Self::Error;
+}
+
+impl<'a> Trait for Inner<'a> {
+    type Error = Outer<Inner<'a>>;
+    fn ready(self) -> Outer<Inner<'a>> { Outer(self) }
+}
+
+fn main() {
+    let value = true;
+    let inner = Inner { value: &value };
+    assert_eq!(inner.ready().0.value, &value);
+}