When I install QT in MacOS 11.3.6, it prompts I need to install xcode
then I install xcode but it was still fruitless.
now, it‘s the solution:
referrence：
https://www.jianshu.com/p/5a6b7fcdf4c3
【QT】Installer requires Xcode Version 5.0.0 for Qt download if toolchain not found
原文：https://www.cnblogs.com/kingdelee/p/10350864.html