Xcode 4: setting NSZombieEnabled environment variable for all projects?-Collection of common programming errors

Have a look at following uris:

Setting environment variables for user processes: http://developer.apple.com/library/mac/#qa/qa1067/_index.html

Runtime Configuration Guide#Environment Variables: http://developer.apple.com/library/mac/#documentation/MacOSX/Conceptual/BPRuntimeConfig/Articles/EnvironmentVars.html

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