Address review comments

src/librustc/mir/mod.rs

@@ -689,13 +689,6 @@ pub struct LocalDecl<'tcx> {
     /// Temporaries and the return place are always mutable.
     pub mutability: Mutability,
 
-    /// `Some(binding_mode)` if this corresponds to a user-declared local variable.
-    ///
-    /// This is solely used for local diagnostics when generating
-    /// warnings/errors when compiling the current crate, and
-    /// therefore it need not be visible across crates. pnkfelix
-    /// currently hypothesized we *need* to wrap this in a
-    /// `ClearCrossCrate` as long as it carries as `HirId`.
     // FIXME(matthewjasper) Don't store in this in `Body`
     pub local_info: LocalInfo<'tcx>,
 
@@ -831,6 +824,10 @@ pub struct LocalDecl<'tcx> {
 #[derive(Clone, Debug, RustcEncodable, RustcDecodable, HashStable, TypeFoldable)]
 pub enum LocalInfo<'tcx> {
     /// A user-defined local variable or function parameter
+    ///
+    /// The `BindingForm` is solely used for local diagnostics when generating
+    /// warnings/errors when compiling the current crate, and therefore it need
+    /// not be visible across crates.
     User(ClearCrossCrate<BindingForm<'tcx>>),
     /// A temporary created that references the static with the given `DefId`.
     StaticRef { def_id: DefId, is_thread_local: bool },

src/librustc_mir/build/expr/as_temp.rs

@@ -65,8 +65,7 @@ fn expr_as_temp(
                 local_decl = local_decl.block_tail(tail_info);
             }
             if let ExprKind::StaticRef { def_id, .. } = expr.kind {
-                let attrs = this.hir.tcx().get_attrs(def_id);
-                let is_thread_local = attrs.iter().any(|attr| attr.check_name(sym::thread_local));
+                let is_thread_local = this.hir.tcx().has_attr(def_id, sym::thread_local);
                 local_decl.local_info = LocalInfo::StaticRef {def_id, is_thread_local };
             }
             this.local_decls.push(local_decl)

src/librustc_mir/hair/mod.rs

@@ -264,7 +264,10 @@ pub enum ExprKind<'tcx> {
         literal: &'tcx Const<'tcx>,
         user_ty: Option<Canonical<'tcx, UserType<'tcx>>>,
     },
-    /// A literal containing the address of a `static`
+    /// A literal containing the address of a `static`.
+    ///
+    /// This is only distinguished from `Literal` so that we can register some
+    /// info for diagnostics.
     StaticRef {
         literal: &'tcx Const<'tcx>,
         def_id: DefId,