升级xcode 后 Qt 出问题了，google 找到了解决方法。
http://stackoverflow.com/questions/33728905/qt-creator-project-error-xcode-not-set-up-properly-you-may-need-to-confirm-t
~> Xcode 8
This problem occurs when command line tools are installed after Xcode is installed. What happens is the Xcode-select developer directory gets pointed to /Library/Developer/CommandLineTools.
Step 1:
Point Xcode-select to the correct Xcode Developer directory with the command:
sudo xcode-select -switch /Applications/Xcode.app/Contents/Developer
Step 2:
Confirm the license agreement with the command:
xcodebuild -license
This will prompt you to read through the license agreement.
Enter agree to accept the terms.
>= Xcode 8
Step 1:
As Bruce said, this happens when Qt tries to find xcrun when it should be looking for xcodebuild.
Open the file:
Qt_install_folder/5.7/clang_64/mkspecs/features/mac/default_pre.prf
Step 2:
Replace:
isEmpty($$list($$system(“/usr/bin/xcrun -find xcrun 2>/dev/null”))))
With:
isEmpty($$list($$system(“/usr/bin/xcrun -find xcodebuild 2>/dev/null”)))