Conflicting types的报错
mac上xcode其实给出的错误信息比较多，而且非常有用，大概报错如下：
Conflicting types for 'glDepthRange': In file included from xxx.cpp In file included from xxx.cpp In file included from xxx.cpp Expanded from macro 'glDepthRangef' revious declaration is here 复制代码
我是因为OpenGL的头文件必须在glew.h前声明，所以对头文件的引入顺序有要求
一定要仔细的排查In file included from，排查这个代码里面的include，确保include嵌套也不会出问题，确保里面的顺序。
vtable for xxx
‘
: "vtable for TouchLayer", referenced from: : A missing vtable usually means the first non-inline virtual member function has no definition. 复制代码
大概意思就是有虚函数没有实现，但是我仔细检查了代码，不存在这个问题，因为我使用的是cmake，所以排查后发现，cpp文件没有加入到工程里面，加入到里面就正常通过编译了。
