用这个：$$quote()
如何添加库？看下面添加mysql路径的例子:
INCLUDEPATH += $$quote(C:Program Files (x86)MySQLMySQL Server 5.6include)
LIBS += -L$$quote(C:Program Files (x86)MySQLMySQL Server 5.6lib) -llibmysql
http://blog.163.com/fafaly@126/blog/static/131693298201510353425223/