Reset Xcode. Clean, clear module cache, Derived Data and Xcode Caches. You can thank me later.

resetXcodeCarthage.sh

#!/bin/bash
killall Xcode
xcrun -k
xcodebuild -alltargets clean
rm -rf "$(getconf DARWIN_USER_CACHE_DIR)/org.llvm.clang/ModuleCache"
rm -rf "$(getconf DARWIN_USER_CACHE_DIR)/org.llvm.clang.$(whoami)/ModuleCache"
rm -rf ~/Library/Developer/Xcode/DerivedData/*
rm -rf ~/Library/Caches/com.apple.dt.Xcode/*
open /Applications/Xcode.app

rm -rf ~/Library/Caches/org.carthage.CarthageKit