安装QT完成后，无法执行c++项目的构建:

Could not determine which "make" command to run. Check the "make" step in the build configuration.
Error while building/deploying project xxx (kit: Desktop Qt 5.10.1 GCC 64bit)
When executing step "qmake"

一般以为是qmake或make问题，但其实是C++的编译工具没指定: