Compiling Cloudera CHD2 on Mac OsX

Download the src tarball.
Download patch for
HADOOP-3659.
Make sure you have MacPorts and zlib installed.
Untar hadoop-0.20.1+169.68.tar.gz

tar -xzf hadoop-0.20.1+169.68.tar.gz

Cd into hadoop-0.20.1+169.68

cd hadoop-0.20.1+169.68

Apply patch

cat HADOOP-3659.patch | patch -p0 

Rerun autoconf

(cd cd src/native/; autoconf)

Compile

ant compile-native

THE END!
This worked for me.