Invoke generated lexer along with baseline lexer to compare results.

src/lexer/lexer.gyp

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 23 matching lines @@
   'targets': [
     {
       'target_name': 'lexer-shell',
       'type': 'executable',
       'dependencies': [
         '../../tools/gyp/v8.gyp:v8',
       ],
       # Generated source files need this explicitly:
       'include_dirs+': [
         '../../src',
+        '../../src/lexer',
       ],
       'sources': [
         'lexer-shell.cc',
-# TODO: fix compiler errors and add '<(SHARED_INTERMEDIATE_DIR)/lexer.cc',
+        'lexer.h',
+        '<(SHARED_INTERMEDIATE_DIR)/lexer.cc',
       ],
       'conditions': [
         ['v8_enable_i18n_support==1', {
           'dependencies': [
             '<(icu_gyp_path):icui18n',
             '<(icu_gyp_path):icuuc',
           ],
         }],
       ],
       'actions': [
@@ skipping 11 matching lines @@
             '-c',
             '--output',
             '<(SHARED_INTERMEDIATE_DIR)/lexer.cc',
             '../../src/lexer/lexer.re',
           ],
         },
       ],
     },
   ],
 }