Using Xcode 4.5.1. Our project has been building fine for the last three months, but suddenly, when I try to build, it says "Build failed", but does not show any errors on the triangle exclamation mark tab, nor does it give a reason when it pops up build failed. We have not changed the bundle identifier, or any other project properties. I tried a clean, then build, but no luck. What may be causing
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