If you are getting build failures in Xcode for a C++ program with similar errors then try this fix.
15 duplicate symbols for architecture x86_64
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
- You can avoid declaring variables in the header and move them to implementation.
- Or you can declare all the variables in the header file as static.