Pandas no longer builds on OS X after installing Xcode 5.1
After "upgrading" to Xcode 5.1, I can no longer build Pandas on OS X 10.9.2. I'm wondering if anyone has successfully done so. I get the following when running build_ext:

```
python setup.py build_ext --inplace
running build_ext
skipping 'pandas/index.c' Cython extension (up-to-date)
building 'pandas.index' extension
creating build
creating build/temp.macosx-10.9-intel-2.7
creating build/temp.macosx-10.9-intel-2.7/pandas
creating build/temp.macosx-10.9-intel-2.7/pandas/src
creating build/temp.macosx-10.9-intel-2.7/pandas/src/datetime
cc -fno-strict-aliasing -fno-common -dynamic -arch x86_64 -arch i386 -g -Os -pipe -fno-common -fno-strict-aliasing -fwrapv -mno-fused-madd -DENABLE_DTRACE -DMACOSX -DNDEBUG -Wall -Wstrict-prototypes -Wshorten-64-to-32 -DNDEBUG -g -fwrapv -Os -Wall -Wstrict-prototypes -DENABLE_DTRACE -arch x86_64 -arch i386 -pipe -Ipandas/src/klib -Ipandas/src -I/Library/Python/2.7/site-packages/numpy-1.9.0.dev_297f54b-py2.7-macosx-10.9-intel.egg/numpy/core/include -I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c pandas/index.c -o build/temp.macosx-10.9-intel-2.7/pandas/index.o
clang: error: unknown argument: '-mno-fused-madd' [-Wunused-command-line-argument-hard-error-in-future]
clang: note: this will be a hard error (cannot be downgraded to a warning) in the future
error: command 'cc' failed with exit status 1
make: *** [tseries] Error 1
```

After a little digging around, I noticed some folks got rid of some clang problems with `export ARCHFLAGS="-Wno-error=unused-command-line-argument-hard-error-in-future"`, so I did that. I got a little further, but it [still failed](http://d.pr/f/cPOy).

Any suggestions for a fix are most welcome!
