rustc_mir: use the right type for associated const literals.

Author: eddyb

src/librustc_mir/hair/cx/expr.rs

@@ -927,7 +927,7 @@ fn convert_path_expr<'a, 'tcx>(
             ExprKind::Literal {
                 literal: cx.tcx.mk_const(ty::Const {
                     val: ConstValue::Unevaluated(def_id, substs),
-                    ty: cx.tcx.type_of(def_id),
+                    ty: cx.tables().node_type(expr.hir_id),
                 }),
                 user_ty,
             }

src/test/ui/dropck/dropck_trait_cycle_checked.stderr

@@ -2,7 +2,7 @@ error[E0597]: `o2` does not live long enough
   --> $DIR/dropck_trait_cycle_checked.rs:111:13
    |
 LL |     let (o1, o2, o3): (Box<dyn Obj>, Box<dyn Obj>, Box<dyn Obj>) = (O::new(), O::new(), O::new());
-   |                                                                               -------- cast requires that `o2` is borrowed for `'static`
+   |                                                                     -------- cast requires that `o2` is borrowed for `'static`
 LL |     o1.set0(&o2);
    |             ^^^ borrowed value does not live long enough
 ...
@@ -13,7 +13,7 @@ error[E0597]: `o3` does not live long enough
   --> $DIR/dropck_trait_cycle_checked.rs:112:13
    |
 LL |     let (o1, o2, o3): (Box<dyn Obj>, Box<dyn Obj>, Box<dyn Obj>) = (O::new(), O::new(), O::new());
-   |                                                                                         -------- cast requires that `o3` is borrowed for `'static`
+   |                                                                     -------- cast requires that `o3` is borrowed for `'static`
 LL |     o1.set0(&o2);
 LL |     o1.set1(&o3);
    |             ^^^ borrowed value does not live long enough
@@ -37,7 +37,7 @@ error[E0597]: `o3` does not live long enough
   --> $DIR/dropck_trait_cycle_checked.rs:114:13
    |
 LL |     let (o1, o2, o3): (Box<dyn Obj>, Box<dyn Obj>, Box<dyn Obj>) = (O::new(), O::new(), O::new());
-   |                                                                                         -------- cast requires that `o3` is borrowed for `'static`
+   |                                                                               -------- cast requires that `o3` is borrowed for `'static`
 ...
 LL |     o2.set1(&o3);
    |             ^^^ borrowed value does not live long enough
@@ -49,7 +49,7 @@ error[E0597]: `o1` does not live long enough
   --> $DIR/dropck_trait_cycle_checked.rs:115:13
    |
 LL |     let (o1, o2, o3): (Box<dyn Obj>, Box<dyn Obj>, Box<dyn Obj>) = (O::new(), O::new(), O::new());
-   |                                                                     -------- cast requires that `o1` is borrowed for `'static`
+   |                                                                                         -------- cast requires that `o1` is borrowed for `'static`
 ...
 LL |     o3.set0(&o1);
    |             ^^^ borrowed value does not live long enough
@@ -61,7 +61,7 @@ error[E0597]: `o2` does not live long enough
   --> $DIR/dropck_trait_cycle_checked.rs:116:13
    |
 LL |     let (o1, o2, o3): (Box<dyn Obj>, Box<dyn Obj>, Box<dyn Obj>) = (O::new(), O::new(), O::new());
-   |                                                                               -------- cast requires that `o2` is borrowed for `'static`
+   |                                                                                         -------- cast requires that `o2` is borrowed for `'static`
 ...
 LL |     o3.set1(&o2);
    |             ^^^ borrowed value does not live long enough