Prior to Xcode 4 with LLVM this passed the compiler unnoticed. Assignment within the conditional is perfectly intentional and a Cocoa idiom.
Xcode 4 with LLVM compiler selected never fails to complain, and not just at compile time, as soon as you type it the yellow warning icon appears. Turning off warnings as errors and just ignoring the warning doesn't seem like a good idea. Moving the assignment out of the parentheses wastes space. Having to turn off this warning with a pragma for every new project will become tedious.
How are you dealing with it? What's the new idiom going to be?
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