It sounds like I’m not the only one having problems with Xcode 4 not symbolicating crash logs correctly. Here’s the symptom: I drag crash logs that testers email me into Xcode 4’s organiser, then sit and wait for symbolication to complete. But once it’s done, my logs aren’t symbolicated – they still just show a load of memory locations.

Running the symbolicator at the command line sheds a bit of light on what’s going wrong:

$ /Developer/Platforms/iPhoneOS.platform/Developer/Library/PrivateFrameworks\
> /DTDeviceKit.framework/Versions/A/Resources/symbolicatecrash MyApp_etc.crash

Here’s the output I get:

Can't understand the output from otool ( -> '\/Developer\/Platforms\/
iPhoneOS\.platform\/Developer\/usr\/bin\/otool -arch armv7 -l   
/Users/simon/Library/Developer/Xcode/DerivedData/MyApp-fbxifqioardhgxaitjdftgoejjzz/
Build/Products/Debug-iphonesimulator/MyApp.app/MyApp') at 
/Developer/Platforms/iPhoneOS.platform/Developer/Library/PrivateFrameworks/
DTDeviceKit.framework/Versions/A/Resources/symbolicatecrash line 323.

Hmm… Notice that path to the app?

~/Library/Developer/Xcode/​DerivedData/MyApp-fbxifqioardhgxaitjdftgoejjzz/​Build/Products/Debug-iphonesimulator/​MyApp.app/MyApp

That’s not the right app file – it’s the build output from a Debug build, not an AdHoc build, and worse it’s a Debug build for the iOS simulator.

As you may know, the symbolicator uses Spotlight to find the .app file (and the .dSYM file) it uses to symbolicate a log. And that means that there’s a really simple fix. Adding ~/Library/Developer/Xcode/DerivedData/ to the list of directories that Spotlight doesn’t index makes those build artefacts invisible to Spotlight, and hence the symbolicator. Just open System Preferences, click on Spotlight, switch to the Privacy tab and add that DerivedData folder to the list.

You may now find that the symbolicator has a similar problem with apps installed on the iPhone simulator itself. Adding ~/Library/Application Support/iPhone Simulator/ to Spotlight’s ignore list nails that one.

Now when I run the symbolicator at the command line, I get properly symbolicated output, just as expected.

UPDATE: See the comments on this Stack Overflow answer of mine. This solution is not without its gotchas; it can interfere with correct running of the Instruments app.