duplicate symbol _mCollecatView in:
/Users/Rubert/Library/Developer/Xcode/DerivedData/ChengDuHidengDangerManage-bktvlkdyhtfruecsycmmvjohrqul/Build/Intermediates/ChengDuHidengDangerManage.build/Debug-iphoneos/ChengDuHidengDangerManage.build/Objects-normal/arm64/MapViewController.o
/Users/Rubert/Library/Developer/Xcode/DerivedData/ChengDuHidengDangerManage-bktvlkdyhtfruecsycmmvjohrqul/Build/Intermediates/ChengDuHidengDangerManage.build/Debug-iphoneos/ChengDuHidengDangerManage.build/Objects-normal/arm64/DangerMapViewController.o
duplicate symbol _dangerInfoView in:
/Users/Rubert/Library/Developer/Xcode/DerivedData/ChengDuHidengDangerManage-bktvlkdyhtfruecsycmmvjohrqul/Build/Intermediates/ChengDuHidengDangerManage.build/Debug-iphoneos/ChengDuHidengDangerManage.build/Objects-normal/arm64/MapViewController.o
/Users/Rubert/Library/Developer/Xcode/DerivedData/ChengDuHidengDangerManage-bktvlkdyhtfruecsycmmvjohrqul/Build/Intermediates/ChengDuHidengDangerManage.build/Debug-iphoneos/ChengDuHidengDangerManage.build/Objects-normal/arm64/DangerMapViewController.o
duplicate symbol _dangerInfoBtn in:
/Users/Rubert/Library/Developer/Xcode/DerivedData/ChengDuHidengDangerManage-bktvlkdyhtfruecsycmmvjohrqul/Build/Intermediates/ChengDuHidengDangerManage.build/Debug-iphoneos/ChengDuHidengDangerManage.build/Objects-normal/arm64/MapViewController.o
/Users/Rubert/Library/Developer/Xcode/DerivedData/ChengDuHidengDangerManage-bktvlkdyhtfruecsycmmvjohrqul/Build/Intermediates/ChengDuHidengDangerManage.build/Debug-iphoneos/ChengDuHidengDangerManage.build/Objects-normal/arm64/DangerMapViewController.o
duplicate symbol _pointAnnotation in:
/Users/Rubert/Library/Developer/Xcode/DerivedData/ChengDuHidengDangerManage-bktvlkdyhtfruecsycmmvjohrqul/Build/Intermediates/ChengDuHidengDangerManage.build/Debug-iphoneos/ChengDuHidengDangerManage.build/Objects-normal/arm64/MapViewController.o
/Users/Rubert/Library/Developer/Xcode/DerivedData/ChengDuHidengDangerManage-bktvlkdyhtfruecsycmmvjohrqul/Build/Intermediates/ChengDuHidengDangerManage.build/Debug-iphoneos/ChengDuHidengDangerManage.build/Objects-normal/arm64/DangerMapViewController.o
duplicate symbol _userLocation in:
/Users/Rubert/Library/Developer/Xcode/DerivedData/ChengDuHidengDangerManage-bktvlkdyhtfruecsycmmvjohrqul/Build/Intermediates/ChengDuHidengDangerManage.build/Debug-iphoneos/ChengDuHidengDangerManage.build/Objects-normal/arm64/MapViewController.o
/Users/Rubert/Library/Developer/Xcode/DerivedData/ChengDuHidengDangerManage-bktvlkdyhtfruecsycmmvjohrqul/Build/Intermediates/ChengDuHidengDangerManage.build/Debug-iphoneos/ChengDuHidengDangerManage.build/Objects-normal/arm64/DangerMapViewController.o
ld: 6 duplicate symbols for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
==============================================
这个问题是由于两个类中有2个相同的全局变量，把一个类中的变量名改下就可以了