Undefined symbols for architecture armv7:
"OBJC_CLASS$_ViewController", referenced from:
objc-class-ref in ViewController.o
project.pbxproj工程文件更新不完全，缺失部分提交的文件名，更新（实在不行拉一下）。

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:-1: object file (/Users/~~~/Desktop/EasyLoan/EasyLoan/thirdparty/STCardSDK/STResource/libIDCardBankCard.a(__all.a.o)) was built for newer iOS version (9.3) than being linked (8.0)
提示的这个第三方或者什么文件支持的最低版本高于当前APP设定的版本。

Undefined symbols for architecture arm64: "OBJC_CLASS$_ 类名", referenced from..XX.o
XX.m文件中引用了前一个类，工程中类缺失导致。
工程中补全后在build phases中comlile sources 中添加。

待补充》》》