Caius Theory

Now with even more cowbell…

Install GCC-4.2.1 (Apple build 5666.3) with Xcode 4.2

As of Xcode 4.2 Apple have stopped bundling GCC with it, shipping only the (mostly) compatible llvm-gcc binary instead. The suggested fix is to install GCC using the osx-gcc-installer project. However, I wanted to build and install it from source, which apple provides at

You should already have installed Xcode 4.2 from the app store, then basically the following steps are to grab the tarball from the 4.1 developer tools source, unpack & compile it, then install it into the right places.

Update 2016-07-03: I'd suggest just using homebrew to install this these days:

brew install homebrew/dupes/apple-gcc42


# Grab and unpack the tarball
mkdir ~/tmp && cd ~/tmp
curl -O
tar zxf gcc-5666.3.tar.gz
cd gcc-5666.3

# Setup some stuff it requires
mkdir -p build/obj build/dst build/sym
# And then build it. You should go make a cup of tea or five whilst this runs.
gnumake install RC_OS=macos RC_ARCHS='i386 x86_64' TARGETS='i386 x86_64' \
  SRCROOT=`pwd` OBJROOT=`pwd`/build/obj DSTROOT=`pwd`/build/dst \

# And finally install it
sudo ditto build/dst /

And now you should have gcc-4.2 in your $PATH, available to build all the things that llvm-gcc fails to compile.