---

yaml
---
r: 233391
b: refs/heads/beta
c: ad700ab
h: refs/heads/master
i:
  233389: 0d96d4c
  233387: 524562e
  233383: 94e54b8
  233375: 754b5b5
v: v3

Author: nikomatsakis

[refs]

@@ -23,7 +23,7 @@ refs/tags/0.9: 36870b185fc5f5486636d4515f0e22677493f225
 refs/tags/0.10: ac33f2b15782272ae348dbd7b14b8257b2148b5a
 refs/tags/0.11.0: e1247cb1d0d681be034adb4b558b5a0c0d5720f9
 refs/tags/0.12.0: f0c419429ef30723ceaf6b42f9b5a2aeb5d2e2d1
-refs/heads/beta: fda9b8396057426e86409fd75c69d896b05c372e
+refs/heads/beta: ad700abea4c6718628a4ceccccdad6a633f1dd9c
 refs/tags/1.0.0-alpha: e42bd6d93a1d3433c486200587f8f9e12590a4d7
 refs/heads/tmp: 370fe2786109360f7c35b8ba552b83b773dd71d6
 refs/tags/1.0.0-alpha.2: 4c705f6bc559886632d3871b04f58aab093bfa2f

branches/beta/src/librustc/middle/ty.rs

@@ -6233,13 +6233,18 @@ impl<'tcx> ctxt<'tcx> {
     /// themselves. This should really be a unique type; `FreshTy(0)` is a
     /// popular choice.
     ///
+    /// NB: in some cases, particularly around higher-ranked bounds,
+    /// this function returns a kind of conservative approximation.
+    /// That is, all regions returned by this function are definitely
+    /// required, but there may be other region bounds that are not
+    /// returned, as well as requirements like `for<'a> T: 'a`.
+    ///
     /// Requires that trait definitions have been processed so that we can
     /// elaborate predicates and walk supertraits.
     pub fn required_region_bounds(&self,
                                   erased_self_ty: Ty<'tcx>,
                                   predicates: Vec<ty::Predicate<'tcx>>)
-                                  -> Vec<ty::Region>
-    {
+                                  -> Vec<ty::Region>    {
         debug!("required_region_bounds(erased_self_ty={:?}, predicates={:?})",
                erased_self_ty,
                predicates);
@@ -6268,11 +6273,7 @@ impl<'tcx> ctxt<'tcx> {
                         // construct such an object, but this seems
                         // correct even if that code changes).
                         if t == erased_self_ty && !r.has_escaping_regions() {
-                            if r.has_escaping_regions() {
-                                Some(ty::ReStatic)
-                            } else {
-                                Some(r)
-                            }
+                            Some(r)
                         } else {
                             None
                         }