Fix string for raw pointer deref suggestion

Author: varkor

src/librustc_typeck/check/mod.rs

@@ -3386,11 +3386,13 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                         }
                     }
                     ty::RawPtr(..) => {
-                        let base = self.tcx.hir().node_to_pretty_string(base.id);
+                        let base = self.tcx.sess.source_map()
+                            .span_to_snippet(base.span)
+                            .unwrap_or_else(|_| self.tcx.hir().node_to_pretty_string(base.id));
                         let msg = format!("`{}` is a raw pointer; try dereferencing it", base);
                         let suggestion = format!("(*{}).{}", base, field);
                         err.span_suggestion_with_applicability(
-                            field.span,
+                            expr.span,
                             &msg,
                             suggestion,
                             Applicability::MaybeIncorrect,

src/test/ui/issues/issue-11004.stderr

@@ -2,13 +2,17 @@ error[E0609]: no field `x` on type `*mut A`
   --> $DIR/issue-11004.rs:17:21
    |
 LL |     let x : i32 = n.x; //~ no field `x` on type `*mut A`
-   |                     ^ help: `n` is a raw pointer; try dereferencing it: `(*n).x`
+   |                   --^
+   |                   |
+   |                   help: `n` is a raw pointer; try dereferencing it: `(*n).x`
 
 error[E0609]: no field `y` on type `*mut A`
   --> $DIR/issue-11004.rs:18:21
    |
 LL |     let y : f64 = n.y; //~ no field `y` on type `*mut A`
-   |                     ^ help: `n` is a raw pointer; try dereferencing it: `(*n).y`
+   |                   --^
+   |                   |
+   |                   help: `n` is a raw pointer; try dereferencing it: `(*n).y`
 
 error: aborting due to 2 previous errors
 

src/test/ui/parenthesised-deref-suggestion.rs

@@ -0,0 +1,8 @@
+struct Session {
+    opts: u8,
+}
+
+fn main() {
+    let sess: &Session = &Session { opts: 0 };
+    (sess as *const Session).opts; //~ ERROR no field `opts` on type `*const Session`
+}

src/test/ui/parenthesised-deref-suggestion.stderr

@@ -0,0 +1,12 @@
+error[E0609]: no field `opts` on type `*const Session`
+  --> $DIR/parenthesised-deref-suggestion.rs:7:30
+   |
+LL |     (sess as *const Session).opts; //~ ERROR no field `opts` on type `*const Session`
+   |                              ^^^^
+help: `(sess as *const Session)` is a raw pointer; try dereferencing it
+   |
+LL |     (*(sess as *const Session)).opts; //~ ERROR no field `opts` on type `*const Session`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0609`.

src/test/ui/unsafe/unsafe-fn-autoderef.stderr

@@ -2,7 +2,9 @@ error[E0609]: no field `f` on type `*const Rec`
   --> $DIR/unsafe-fn-autoderef.rs:29:14
    |
 LL |     return p.f; //~ ERROR no field `f` on type `*const Rec`
-   |              ^ help: `p` is a raw pointer; try dereferencing it: `(*p).f`
+   |            --^
+   |            |
+   |            help: `p` is a raw pointer; try dereferencing it: `(*p).f`
 
 error: aborting due to previous error