Add E0614

Author: GuillaumeGomez

src/librustc_typeck/check/mod.rs

@@ -3217,15 +3217,15 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                                         .join(", ");
 
             struct_span_err!(tcx.sess, span, E0063,
-                        "missing field{} {}{} in initializer of `{}`",
-                        if remaining_fields.len() == 1 {""} else {"s"},
-                        remaining_fields_names,
-                        truncated_fields_error,
-                        adt_ty)
-                        .span_label(span, format!("missing {}{}",
-                            remaining_fields_names,
-                            truncated_fields_error))
-                        .emit();
+                             "missing field{} {}{} in initializer of `{}`",
+                             if remaining_fields.len() == 1 { "" } else { "s" },
+                             remaining_fields_names,
+                             truncated_fields_error,
+                             adt_ty)
+                            .span_label(span, format!("missing {}{}",
+                                        remaining_fields_names,
+                                        truncated_fields_error))
+                            .emit();
         }
     }
 
@@ -3458,10 +3458,9 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                             oprnd_t = self.make_overloaded_lvalue_return_type(method).ty;
                             self.write_method_call(expr.id, method);
                         } else {
-                            self.type_error_message(expr.span, |actual| {
-                                format!("type `{}` cannot be \
-                                        dereferenced", actual)
-                            }, oprnd_t);
+                            type_error_struct!(tcx.sess, expr.span, oprnd_t, E0614,
+                                               "type `{}` cannot be dereferenced",
+                                               oprnd_t).emit();
                             oprnd_t = tcx.types.err;
                         }
                     }

src/librustc_typeck/diagnostics.rs

@@ -4286,6 +4286,27 @@ println!("x: {} y: {}", s.x, s.y);
 ```
 "##,
 
+E0614: r##"
+Attempted to dereference a variable which cannot be dereferenced.
+
+Erroneous code example:
+
+```compile_fail,E0614
+let y = 0u32;
+*y; // error: type `u32` cannot be dereferenced
+```
+
+Only types implementing `std::ops::Deref` can be dereferenced (such as `&T`).
+Example:
+
+```
+let y = 0u32;
+let x = &y;
+// So here, `x` is a `&u32`, so we can dereference it:
+*x; // ok!
+```
+"##,
+
 E0617: r##"
 Attempted to pass an invalid type of variable into a variadic function.
 

src/test/compile-fail/E0614.rs

@@ -0,0 +1,14 @@
+// Copyright 2017 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.
+
+fn main() {
+    let y = 0u32;
+    *y; //~ ERROR E0614
+}