XCode, Lion, GCC Oh My!!

My curiosity always pushes me to upgrade to the latest OS despite the caution issued to me by Ben. I upgraded to Lion and quickly found that XCode 3.2.6 cannot be installed on Lion. We're not ready to move completely to XCode 4 just yet so I had to find a work around. Luckily, there is one.

Basically, you just have to follow these simple steps:

• Mount the Xcode 3.2.6 DMG
• Open Terminal
• Enter the commands:

  export COMMAND_LINE_INSTALL=1
  open "/Volumes/Xcode and iOS SDK/Xcode and iOS SDK.mpkg"

Because I need to run XCode 4 and XCode 3.2.6 side by side, I installed XCode 3.2.6 to /Developer-3.2.6 and let XCode 4 have the default /Developer directory.

Ok that gets me a working copy of XCode 3.2.6 as well as the SDKs that I need which are 10.5 and 10.6...but I'm not out of the woods yet because the X-Plane Scenery Tools requires the 10.5 SDK. I have it so there's no problem right? WRONG! The GCC being used by the system is in /Developer and if you take a look at /Developer/SDKs you'll see 10.6 and 10.7 but no 10.5. That's because 10.5 lives in /Developer-3.2.6 but GCC won't be looking there. My solution was to create a symbolic link (the linux kind ln -s, not the Mac Alias kind) in the /Developer/SDKs folder that points to the /Developer-3.2.6/SDKs folder. The actual command was:

ln -s /Developer-3.2.6/SDKs/MacOSX10.5.sdk /Developer/SDKs/MacOSX10.5.sdk

So now with that done, GCC now has access to the right SDKs. The finder view of /Developer/SDKs should look like this:

At this point, I tried to compile the libs necessary for the X-Plane Scenery Tools again but was hit with one more snag as it was failing to find bits/c++config.h as referenced by iostream.h and a dozen other files. It turns out that the new GCC is a darwin11 version of the compiler. That's fine but if you look at /Developer/SDKs/MacOSX10.5.sdk/usr/include/c++/4.2.1/ you'll notice that there are several folders that are named with respect to the GCC version they're designed for...the ones we care about are:

• i686-apple-darwin*
• x86_64-apple-darwin*

Here's a screenshot of what it looks like on my system:

You'll notice that there's no version for darwin11 which is why the headers cannot be found. The solution once again is a symbolic link. You'll notice that darwin8 and darwin10 are actually really links to darwin9. All that I had to do now is create a symbolic link back to version 9 for the 32bit and 64bit paths. Here's the commands:

ln -s i686-apple-darwin9 i686-apple-darwin11

ln -s x86_64-apple-darwin9 x86_64-apple-darwin11

After these steps, the universe seemed to be back in order again. XCode 4 and XCode 3.2.6 co-exist properly and the scenery tools compile using the newer version of GCC even using the older 10.5 SDK.