Set default multi-core compilation qt source: http://stackoverflow.com/questions/8860712/setting-default-make-options-for-qt-creator
Setting up multi-core compilation for a single project: Author Learning Sea Ark: Speeding up the compilation of QT projects: http://blog.csdn.net/favory/article/details/50061141
Menu bar->tools->options->build and run->build kit->click auto-detect content->find Environment on the same page->click change->add MAKEFLAGS=-j4 in the pop-up window
-j4 : Indicates that the four cores of the cup are added to the compilation
Figure 1
Figure II
