duplicate symbols for architecture arm64 after Xcode 8.0 update

Question

I get duplicate symbols error after I updated my Xcode. (find the code down) Does anybody get this too? And how could be solved?

I tried to remove

Answer 1

for my case, Xcode 9 , we were declaring constants in some header file

Constants.h

static NSString *const kSomeString = @"SomeString";

so importing Constants.h in multiple .m files causes the duplicated symbols

Solution:

Constants.h

extern NSString * const kSomeString;

Constants.m

NSString *const kSomeString = @"SomeString";