Xcode C++ :: Duplicate Symbols for Architecture x86_64

Question

I am new to Xcode and when I build the following code (an MWE), I get the following error

ld: 3 duplicate symbols for architecture x86_64 clang: err

Answer 1

For me, changing 'No Common Blocks' from Yes to No ( under Targets->Build Settings->Apple LLVM - Code Generation ) fixed the problem.

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