title: GCC error: command 'gcc-4.0' failed with exit status 1
body: <p>I am trying to install Fabric into a Virtualenv / Django 1.3.1 / OS X Lion with Xcode 4.2. This error seems to be <a href="https://stackoverflow.com/questions/6906385/mac-osx-lion-virtualenv-pil-install-gcc-error">fairly prevalent</a> but I can't seem to find an answer when you are running Python 2.7 &amp; Xcode 4.2.</p>
  
  <p>I'm running:</p>
  
  <p>Python 2.7 (r27:82508, Jul  3 2010, 21:12:11) 
  [GCC 4.0.1 (Apple Inc. build 5493)] </p>
  
  <p>How do I execute gcc-4.0 instead of gcc-4.0.1?</p>
  
  <p>Thanks!</p>
  
  <p>The full Fabric install + error:</p>
  
  <pre><code>Requirement already satisfied (use --upgrade to upgrade): fabric in ./lib/python2.7/site-packages/Fabric-0.1.0-py2.7.egg
  Requirement already satisfied (use --upgrade to upgrade): paramiko&gt;=1.7,&lt;2.0 in ./lib/python2.7/site-packages/paramiko-1.7.7.1-py2.7.egg (from fabric)
  Downloading/unpacking pycrypto&gt;=2.1 (from paramiko&gt;=1.7,&lt;2.0-&gt;fabric)
    Running setup.py egg_info for package pycrypto
  
  Installing collected packages: pycrypto
    Running setup.py install for pycrypto
      warning: GMP or MPIR library not found; Not building Crypto.PublicKey._fastmath.
      building 'Crypto.Hash.MD2' extension
      gcc-4.0 -fno-strict-aliasing -fno-common -dynamic -arch i386 -arch ppc -arch x86_64 -std=c99 -O3 -fomit-frame-pointer -Isrc/ -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c src/MD2.c -o build/temp.macosx-10.5-fat3-2.7/src/MD2.o
      unable to execute gcc-4.0: No such file or directory
      error: command 'gcc-4.0' failed with exit status 1
      Complete output from command /Users/emilepetrone/Sites/newsite/salesapp/bin/python -c "import setuptools;__file__='/Users/emilepetrone/Sites/newsite/salesapp/build/pycrypto/setup.py';exec(compile(open(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --single-version-externally-managed --record /var/folders/hv/yjvyz6g96xd4c4nbg3hgtk9c0000gn/T/pip-R0wRzk-record/install-record.txt --install-headers /Users/emilepetrone/Sites/newsite/salesapp/bin/../include/site/python2.7:
      running install
  
  running build
  
  running build_configure
  
  running build_py
  
  running build_ext
  
  warning: GMP or MPIR library not found; Not building Crypto.PublicKey._fastmath.
  
  building 'Crypto.Hash.MD2' extension
  
  gcc-4.0 -fno-strict-aliasing -fno-common -dynamic -arch i386 -arch ppc -arch x86_64 -std=c99 -O3 -fomit-frame-pointer -Isrc/ -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c src/MD2.c -o build/temp.macosx-10.5-fat3-2.7/src/MD2.o
  
  unable to execute gcc-4.0: No such file or directory
  
  error: command 'gcc-4.0' failed with exit status 1
  </code></pre>