auto merge of #17761 : bkoropoff/rust/issue-17758, r=alexcrichton

This fixes an ICE and closes issue #17758

src/librustc/middle/typeck/infer/error_reporting.rs

@@ -869,6 +869,19 @@ impl<'a, 'tcx> ErrorReporting for InferCtxt<'a, 'tcx> {
                         ast::TypeImplItem(_) => None,
                     }
                 },
+                ast_map::NodeTraitItem(ref item) => {
+                    match **item {
+                        ast::ProvidedMethod(ref m) => {
+                            Some((m.pe_fn_decl(),
+                                  m.pe_generics(),
+                                  m.pe_fn_style(),
+                                  m.pe_ident(),
+                                  Some(&m.pe_explicit_self().node),
+                                  m.span))
+                        }
+                        _ => None
+                    }
+                }
                 _ => None
             },
             None => None

src/test/compile-fail/issue-17758.rs

@@ -0,0 +1,22 @@
+// Copyright 2014 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.
+
+// Test that regionck suggestions in a provided method of a trait
+// don't ICE
+
+trait Foo<'a> {
+    fn foo(&'a self);
+    fn bar(&self) {
+        self.foo();
+        //~^ ERROR mismatched types: expected `&'a Self`, found `&Self` (lifetime mismatch)
+    }
+}
+
+fn main() {}