我看到一个非常烦人的错误，我真的不知道如何处理。这似乎很常见，我几乎尝试了所有能找到的解决方案，但都无济于事。
我正在尝试使用 pip 安装库。 gevent、psycopg2 和 greenlet 都遇到过这个问题。问题似乎是我的计算机找不到应提供 XCode 4：gcc-4.2 的特定 C 编译器。这是一个示例（尽管也在 virtualenv 中进行了尝试）。
Last login: Sun Jul 29 23:35:54 on ttys000
*******s-MacBook-Pro:~ ******$ pip install gevent
Downloading/unpacking gevent
Downloading gevent-0.13.7.tar.gz (288Kb): 288Kb downloaded
Running setup.py egg_info for package gevent
Downloading/unpacking greenlet (from gevent)
Downloading greenlet-0.4.0.zip (72Kb): 72Kb downloaded
Running setup.py egg_info for package greenlet
Installing collected packages: gevent, greenlet
Running setup.py install for gevent
building 'gevent.core' extension
gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -isysroot /Developer/SDKs/MacOSX10.6.sdk -arch i386 -arch x86_64 -g -O2 -DNDEBUG -g -O3 -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c gevent/core.c -o build/temp.macosx-10.6-intel-2.7/gevent/core.o
In file included from /Library/Frameworks/Python.framework/Versions/2.7/include/python2.7/unicodeobject.h:4,
from /Library/Frameworks/Python.framework/Versions/2.7/include/python2.7/Python.h:85,
from gevent/core.c:4:
/Developer/SDKs/MacOSX10.6.sdk/usr/include/stdarg.h:4:25: error: stdarg.h: No such file or directory
In file included from gevent/core.c:225:
gevent/libevent.h:9:19: error: event.h: No such file or directory
gevent/libevent.h:38:20: error: evhttp.h: No such file or directory
gevent/libevent.h:39:19: error: evdns.h: No such file or directory
gevent/core.c:361: error: field ‘ev’ has incomplete type
gevent/core.c:741: warning: parameter names (without types) in function declaration
....more like this but i'll skip it for now....
copying gevent/wsgi.py -> build/lib.macosx-10.6-intel-2.7/gevent
running build_ext
building 'gevent.core' extension
creating build/temp.macosx-10.6-intel-2.7
creating build/temp.macosx-10.6-intel-2.7/gevent
gcc-4.2 -fno-strict-aliasing -fno-common -dynamic -isysroot /Developer/SDKs/MacOSX10.6.sdk -arch i386 -arch x86_64 -g -O2 -DNDEBUG -g -O3 -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c gevent/core.c -o build/temp.macosx-10.6-intel-2.7/gevent/core.o
In file included from /Library/Frameworks/Python.framework/Versions/2.7/include/python2.7/unicodeobject.h:4,
from /Library/Frameworks/Python.framework/Versions/2.7/include/python2.7/Python.h:85,
from gevent/core.c:4:
/Developer/SDKs/MacOSX10.6.sdk/usr/include/stdarg.h:4:25: error: stdarg.h: No such file or directory
In file included from gevent/core.c:225:
gevent/libevent.h:9:19: error: event.h: No such file or directory
gevent/libevent.h:38:20: error: evhttp.h: No such file or directory
gevent/libevent.h:39:19: error: evdns.h: No such file or directory
....more like this as well....
gevent/core.c:15559: warning: assignment makes pointer from integer without a cast
gevent/core.c: At top level:
gevent/core.c:21272: error: expected ‘)’ before ‘val’
lipo: can't figure out the architecture type of: /var/folders/xc/f2mg5kn96kqdr3tj19pgyhs00000gn/T//cckLxkJ2.out
error: command 'gcc-4.2' failed with exit status 1
Command /Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python -c "import setuptools;__file__='/Users/******/build/gevent/setup.py';exec(compile(open(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --single-version-externally-managed --record /var/folders/xc/f2mg5kn96kqdr3tj19pgyhs00000gn/T/pip-yA5oWR-record/install-record.txt failed with error code 1 in /Users/******/build/gevent
Storing complete log in /Users/******/.pip/pip.log
***********s-MacBook-Pro:~ ******$
您可能会问的问题：
1）你尝试过使用virtualenv吗？
是的。我尝试对预先存在的 gcc （位于 /usr/bin/ 目录中）进行符号链接，如下所示：
ln -s /usr/bin/gcc gcc-4.2
ln -s /usr/bin/gcc-4.2 gcc-4.2
ln -s /usr/bin/gcc gcc
这些都不起作用。
2）您是否尝试重新安装XCode？
Yes.
3）你安装了XCode命令行工具吗？
Yes.
4）你确定你有gcc吗？
**********s-MacBook-Pro:~ sanjay$ gcc
i686-apple-darwin11-llvm-gcc-4.2: no input files
5）Python安装？
************s-MacBook-Pro:~ ******$ python
Python 2.7.3 (v2.7.3:70274d53c1dd, Apr 9 2012, 20:52:43)
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
关于可能出现什么问题以及如何解决它有什么想法吗？
我也尝试安装这个：https://github.com/kennethreitz/osx-gcc-installer https://github.com/kennethreitz/osx-gcc-installer。我不知道还能尝试什么。当涉及到 unix-y 编码/安装的事情时，我是一个新手，所以如果有什么地方我做得很糟糕，请指出来。
Thanks!
