respect the tcx's recursion limit when peeling

tests/ui/pattern/deref-patterns/recursion-limit.rs

@@ -0,0 +1,23 @@
+//! Test that implicit deref patterns respect the recursion limit
+#![feature(deref_patterns)]
+#![allow(incomplete_features)]
+#![recursion_limit = "8"]
+
+use std::ops::Deref;
+
+struct Cyclic;
+impl Deref for Cyclic {
+    type Target = Cyclic;
+    fn deref(&self) -> &Cyclic {
+        &Cyclic
+    }
+}
+
+fn main() {
+    match &Box::new(Cyclic) {
+        () => {}
+        //~^ ERROR: reached the recursion limit while auto-dereferencing `Cyclic`
+        //~| ERROR: the trait bound `Cyclic: DerefPure` is not satisfied
+        _ => {}
+    }
+}

tests/ui/pattern/deref-patterns/recursion-limit.stderr

@@ -0,0 +1,18 @@
+error[E0055]: reached the recursion limit while auto-dereferencing `Cyclic`
+  --> $DIR/recursion-limit.rs:18:9
+   |
+LL |         () => {}
+   |         ^^ deref recursion limit reached
+   |
+   = help: consider increasing the recursion limit by adding a `#![recursion_limit = "16"]` attribute to your crate (`recursion_limit`)
+
+error[E0277]: the trait bound `Cyclic: DerefPure` is not satisfied
+  --> $DIR/recursion-limit.rs:18:9
+   |
+LL |         () => {}
+   |         ^^ the trait `DerefPure` is not implemented for `Cyclic`
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0055, E0277.
+For more information about an error, try `rustc --explain E0055`.