Build errors using llvm-gcc
After upgrading to Xcode 4.2, I'm unable to build pandas. As with previous attempts, I have to hand-compile some of the .pyx files in pandas/src, but now even with this, the package will not build. Here is what I get:

```
building 'pandas._cppsandbox' extension
llvm-gcc-4.2 -DNDEBUG -g -fwrapv -Os -Wall -Wstrict-prototypes -I/Users/fonnescj/Developer/include -pipe -arch x86_64 -I/Library/Python/2.7/site-packages/numpy-2.0.0.dev_eb46577_20111130-py2.7-macosx-10.7-x86_64.egg/numpy/core/include -I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c pandas/src/cppsandbox.c -o build/temp.macosx-10.7-x86_64-2.7/pandas/src/cppsandbox.o
pandas/src/cppsandbox.c:235:19: error: utility: No such file or directory
pandas/src/cppsandbox.c:236:15: error: map: No such file or directory
In file included from /Library/Python/2.7/site-packages/numpy-2.0.0.dev_eb46577_20111130-py2.7-macosx-10.7-x86_64.egg/numpy/core/include/numpy/ndarraytypes.h:1972,
                 from /Library/Python/2.7/site-packages/numpy-2.0.0.dev_eb46577_20111130-py2.7-macosx-10.7-x86_64.egg/numpy/core/include/numpy/ndarrayobject.h:17,
                 from /Library/Python/2.7/site-packages/numpy-2.0.0.dev_eb46577_20111130-py2.7-macosx-10.7-x86_64.egg/numpy/core/include/numpy/arrayobject.h:14,
                 from pandas/src/cppsandbox.c:239:
/Library/Python/2.7/site-packages/numpy-2.0.0.dev_eb46577_20111130-py2.7-macosx-10.7-x86_64.egg/numpy/core/include/numpy/npy_deprecated_api.h:11:2: warning: #warning "Using deprecated NumPy API, disable it by #defining NPY_NO_DEPRECATED_API"
pandas/src/cppsandbox.c: In function ‘__pyx_pf_10cppsandbox_map_indices’:
pandas/src/cppsandbox.c:953: error: expected expression before ‘:’ token
pandas/src/cppsandbox.c:985: error: ‘__pyx_v_mapping’ undeclared (first use in this function)
pandas/src/cppsandbox.c:985: error: (Each undeclared identifier is reported only once
pandas/src/cppsandbox.c:985: error: for each function it appears in.)
pandas/src/cppsandbox.c:985: error: ‘std’ undeclared (first use in this function)
pandas/src/cppsandbox.c:985: error: expected ‘;’ before ‘:’ token
pandas/src/cppsandbox.c:953: warning: label ‘std’ defined but not used
error: command 'llvm-gcc-4.2' failed with exit status 1
```

Not sure if this is idiosyncratic, so I will sit tight until others have tried with the llvm compiler.
