compile google V8 error under win7
<p>When i compile google V8 under win7 according to url:<a href="https://github.com/v8/v8/wiki/Building%20with%20Gyp#visual-studio" rel="nofollow">https://github.com/v8/v8/wiki/Building%20with%20Gyp#visual-studio</a>
It shows below error, thanks in advance</p>

<pre><code>      Please follow the instructions at https://www.chromium.org/developers/how-tos/bu
ild-instructions-windows


Traceback (most recent call last):
  File "build/gyp_v8", line 121, in &lt;module&gt;
    gyp_environment.set_environment()
  File "W:\ProjectCodes\V8\build\gyp_environment.py", line 54, in set_environmen
t
    vs_toolchain.SetEnvironmentAndGetRuntimeDllDirs()
  File "W:\ProjectCodes\V8\build\vs_toolchain.py", line 40, in SetEnvironmentAnd
GetRuntimeDllDirs
    Update()
  File "W:\ProjectCodes\V8\build\vs_toolchain.py", line 226, in Update
    subprocess.check_call(get_toolchain_args)
  File "W:\ProjectCodes\V8\third_party\python27\lib\subprocess.py", line 540, in
 check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['W:\\ProjectCodes\\V8\\third_party\\pyt
hon27\\python.exe', 'W:\\ProjectCodes\\depot_tools\\win_toolchain\\get_toolchain
_if_necessary.py', '--output-json', 'W:\\ProjectCodes\\V8\\build\\win_toolchain.
json', 'ee7d718ec60c2dc5d255bbe325909c2021a7efef']' returned non-zero exit statu
s 1 
</code></pre>