Simon Schoeters <p>The System Preferences application on Mac is universal since Snow Leopard: it can run in 32-bit or 64-bit but not at the same time. That's why you have to restart the application when you want to open an older Preference Pane.</p> <p>Today I tried to upgrade the <a href="http://milkcarton.be/apps/lazypoken" title="A poken automounter" class="ext">LazyPoken</a> prefpane as it was still a 32-bit build and the next Mac OS X will probably no longer support the 32-bit System Preferences application. That turned out to be a little harder as expected.</p> <h3>Build settings</h3> <p>First of all you should change your project ARCH flags to tell the gcc compiler it should build for 64-bit. You can do this in Project &rarr; Edit Project Settings, choose the Build tab and look for the Architectures or ARCHS parameter. Choose the 64-bit or Universal mode (if you need to support Tiger).</p> <p>This is not enough however. If you try to build and install your application you&apos;ll notice it&apos;s still running in 32-bit, stubborn prefpane.</p> <p>The 64-bit System Preferences application also uses garbage collection and all 64-bit prefpanes need to support this as well. You can enable this in the same build panel under the Objective-C Garbage Collection or GCC_ENABLE_OBJC_GC parameter. Choose the Supported or Required option, again, depending on what you want to support.</p> <p>Clean and build your application again, check for warnings and try it out. Looking better now?</p> <h3>64-bit gotchas</h3> <ul> <li>Sparkle: make sure to include the With Garbage Collection version of Sparkle, you just activated garbage collection remember?</li> <li>Older frameworks: make sure the frameworks your application depends on compile in 64-bit mode. The Developer Tools installed with Xcode include a tool to check your code for possible 64-bit incompatibilities. Read the <a href="http://developer.apple.com/mac/library/documentation/Cocoa/Conceptual/Cocoa64BitGuide/ConvertingExistingApp/ConvertingExistingApp.html#//apple_ref/doc/uid/TP40004247-CH5-SW1" title="64-bit Trasition Guide for Cocoa" class="ext">Converting an Existing Application to 64-Bit</a> documentation.</li> </ul> <p>Still running into problems? Read the <a href="http://developer.apple.com/mac/library/documentation/UserExperience/Conceptual/PreferencePanes/Articles/UpdatingPreferencePanesforSnowLeopardandBeyond.html" title="Updating Preference Panes for Snow Leopard and Beyond" class="ext">Updating Preference Panes for Snow Leopard and Beyond</a> article from Apple&apos;s Preference Pane Programming Guide.</p> 2010-02-04T00:06:36+01:00 66 8 building-64bit-prefpane 2010-02-04T00:15:10+01:00