Prevent missing idents from causing problems down the line

Author: Nick Cameron

src/librustc_resolve/lib.rs

@@ -3037,6 +3037,10 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                           check_ribs: bool,
                           record_used: bool)
                           -> Option<LocalDef> {
+        if identifier.name == special_idents::invalid.name {
+            return Some(LocalDef::from_def(DefErr));
+        }
+
         // First, check to see whether the name is a primitive type.
         if namespace == TypeNS {
             if let Some(&prim_ty) = self.primitive_type_table

src/librustc_typeck/check/mod.rs

@@ -121,7 +121,7 @@ use syntax::attr;
 use syntax::attr::AttrMetaMethods;
 use syntax::codemap::{self, Span, Spanned};
 use syntax::errors::DiagnosticBuilder;
-use syntax::parse::token::{self, InternedString};
+use syntax::parse::token::{self, InternedString, special_idents};
 use syntax::ptr::P;
 use syntax::util::lev_distance::find_best_match_for_name;
 
@@ -2839,8 +2839,10 @@ fn check_expr_with_unifier<'a, 'tcx, F>(fcx: &FnCtxt<'a, 'tcx>,
                 method_ty
             }
             Err(error) => {
-                method::report_error(fcx, method_name.span, expr_t,
-                                     method_name.node, Some(rcvr), error);
+                if method_name.node != special_idents::invalid.name {
+                    method::report_error(fcx, method_name.span, expr_t,
+                                         method_name.node, Some(rcvr), error);
+                }
                 fcx.write_error(expr.id);
                 fcx.tcx().types.err
             }
@@ -2938,6 +2940,11 @@ fn check_expr_with_unifier<'a, 'tcx, F>(fcx: &FnCtxt<'a, 'tcx>,
             None => {}
         }
 
+        if field.node == special_idents::invalid.name {
+            fcx.write_error(expr.id);
+            return;
+        }
+
         if method::exists(fcx, field.span, field.node, expr_t, expr.id) {
             fcx.type_error_struct(field.span,
                                   |actual| {
@@ -3788,8 +3795,9 @@ pub fn resolve_ty_and_def_ufcs<'a, 'b, 'tcx>(fcx: &FnCtxt<'b, 'tcx>,
                 Some((Some(ty), slice::ref_slice(item_segment), def))
             }
             Err(error) => {
-                method::report_error(fcx, span, ty,
-                                     item_name, None, error);
+                if item_name != special_idents::invalid.name {
+                    method::report_error(fcx, span, ty, item_name, None, error);
+                }
                 fcx.write_error(node_id);
                 None
             }