libsyntax: Stop parsing const.

src/libsyntax/parse/obsolete.rs

@@ -60,6 +60,7 @@ pub enum ObsoleteSyntax {
     ObsoleteConstManagedPointer,
     ObsoletePurity,
     ObsoleteStaticMethod,
+    ObsoleteConstItem,
 }
 
 impl to_bytes::IterBytes for ObsoleteSyntax {
@@ -203,6 +204,11 @@ fn obsolete(&self, sp: span, kind: ObsoleteSyntax) {
                 "`static` notation",
                 "`static` is superfluous; remove it"
             ),
+            ObsoleteConstItem => (
+                "`const` item",
+                "`const` items are now `static` items; replace `const` with \
+                 `static`"
+            ),
         };
 
         self.report(sp, kind, kind_str, desc);

src/libsyntax/parse/parser.rs

@@ -81,6 +81,7 @@
 use parse::obsolete::{ObsoleteMode, ObsoleteImplicitSelf};
 use parse::obsolete::{ObsoleteLifetimeNotation, ObsoleteConstManagedPointer};
 use parse::obsolete::{ObsoletePurity, ObsoleteStaticMethod};
+use parse::obsolete::{ObsoleteConstItem};
 use parse::prec::{as_prec, token_to_binop};
 use parse::token::{can_begin_expr, is_ident, is_ident_or_path};
 use parse::token::{is_plain_ident, INTERPOLATED, special_idents};
@@ -3563,7 +3564,9 @@ fn parse_item_foreign_const(&self, vis: ast::visibility,
         let lo = self.span.lo;
 
         // XXX: Obsolete; remove after snap.
-        if !self.eat_keyword(&~"const") {
+        if self.eat_keyword(&~"const") {
+            self.obsolete(*self.last_span, ObsoleteConstItem);
+        } else {
             self.expect_keyword(&~"static");
         }
 
@@ -3959,6 +3962,9 @@ fn parse_item_or_view_item(
                 (self.is_keyword(&~"static") &&
                     !self.token_is_keyword(&~"fn", &self.look_ahead(1)))) {
             // CONST ITEM
+            if self.is_keyword(&~"const") {
+                self.obsolete(*self.span, ObsoleteConstItem);
+            }
             self.bump();
             let (ident, item_, extra_attrs) = self.parse_item_const();
             return iovi_item(self.mk_item(lo, self.last_span.hi, ident, item_,