rustc: Use spans in some main typeck errors

Author: brson

src/comp/middle/typeck.rs

@@ -2681,13 +2681,15 @@ fn check_main_fn_ty(tcx: &ty::ctxt, main_id: &ast::node_id) {
         ok &=
             num_args == 0u || num_args == 1u && arg_is_argv_ty(tcx, args.(0));
         if !ok {
-            tcx.sess.err("wrong type in main function: found " +
-                             ty_to_str(tcx, main_t));
+            let span = ast_map::node_span(tcx.items.get(main_id));
+            tcx.sess.span_err(span, "wrong type in main function: found " +
+                              ty_to_str(tcx, main_t));
         }
       }
       _ {
-        tcx.sess.bug("main has a non-function type: found" +
-                         ty_to_str(tcx, main_t));
+        let span = ast_map::node_span(tcx.items.get(main_id));
+        tcx.sess.span_bug(span, "main has a non-function type: found" +
+                          ty_to_str(tcx, main_t));
       }
     }
 }