Fix linking of mksnapshot

SConstruct

 # Copyright 2008 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 126 matching lines @@
       # used by the arm simulator.
       'WARNINGFLAGS': ['/wd4996']
     },
     'disassembler:on': {
       'CPPDEFINES':   ['ENABLE_DISASSEMBLER']
     }
   }
 }
 
 
+MKSNAPSHOT_EXTRA_FLAGS = {
+  'gcc': {
+    'os:linux': {
+      'LIBS': ['pthread'],
+    },
+    'os:macos': {
+      'LIBS': ['pthread'],
+    },
+    'os:freebsd': {
+      'LIBS': ['pthread'],
+    },
+    'os:win32': {
+      'LIBS': ['winmm'],
+    },
+  },
+  'msvc': {
+    'all': {
+      'LIBS': ['winmm']
+    }
+  }
+}
+
+
 JSCRE_EXTRA_FLAGS = {
   'gcc': {
     'all': {
       'CPPDEFINES':   ['SUPPORT_UTF8', 'NO_RECURSE', 'SUPPORT_UCP'],
       'WARNINGFLAGS': ['-w']
     },
   },
   'msvc': {
     'all': {
       'CPPDEFINES':   ['SUPPORT_UTF8', 'NO_RECURSE', 'SUPPORT_UCP'],
@@ skipping 376 matching lines @@
 def BuildSpecific(env, mode, env_overrides):
   options = {'mode': mode}
   for option in SIMPLE_OPTIONS:
     options[option] = env[option]
   PostprocessOptions(options)
 
   context = BuildContext(options, env_overrides, samples=SplitList(env['sample']))
 
   library_flags = context.AddRelevantFlags(os.environ, LIBRARY_FLAGS)
   v8_flags = context.AddRelevantFlags(library_flags, V8_EXTRA_FLAGS)
+  mksnapshot_flags = context.AddRelevantFlags(library_flags, MKSNAPSHOT_EXTRA_FLAGS)
   jscre_flags = context.AddRelevantFlags(library_flags, JSCRE_EXTRA_FLAGS)
   dtoa_flags = context.AddRelevantFlags(library_flags, DTOA_EXTRA_FLAGS)
   cctest_flags = context.AddRelevantFlags(v8_flags, CCTEST_EXTRA_FLAGS)
   sample_flags = context.AddRelevantFlags(os.environ, SAMPLE_FLAGS)
   d8_flags = context.AddRelevantFlags(library_flags, D8_FLAGS)
 
   context.flags = {
     'v8': v8_flags,
-    'mksnapshot': v8_flags,
+    'mksnapshot': mksnapshot_flags,
     'jscre': jscre_flags,
     'dtoa': dtoa_flags,
     'cctest': cctest_flags,
     'sample': sample_flags,
     'd8': d8_flags
   }
 
   target_id = mode
   suffix = SUFFIXES[target_id]
   library_name = 'v8' + suffix
@@ skipping 93 matching lines @@
 # version of scons.  Also, there's a bug in some revisions that
 # doesn't allow this flag to be set, so we swallow any exceptions.
 # Lovely.
 try:
   SetOption('warn', 'no-deprecated')
 except:
   pass
 
 
 Build()