It's the same for 7 and 8. From the Project Navigator, select the project. In the main panel, at the top left, select the target. Now the main panel should have General, Resource Tags, Build Settings, Build Phases, & Build Rules along the top. Select Build Settings, select All. Scroll down to "Apple LLVM 8.0 Language C++" and expand it. Change "C++ Language Dialect" to "C++11 [-std=c++11]".
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…