clang: error: clang frontend command failed with exit code 70 (use -v to see invocation)

Question

I don't know what causes it.

It does not happen at iPhone 5 and simulators. It have been happened only my original device iPhone 7.

fatal error: error in backend: Error while trying to spill X0 from class GPR64: Cannot scavenge register without an emergency spill slot!
clang: error: clang frontend command failed with exit code 70 (use -v to see invocation)
Apple LLVM version 9.0.0 (clang-900.0.34.1)
Target: aarch64-apple-darwin16.7.0
Thread model: posix
InstalledDir: /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
clang: note: diagnostic msg: PLEASE submit a bug report to http://developer.apple.com/bugreporter/ and include the crash backtrace, preprocessed source, and associated run script.
clang: note: diagnostic msg: 
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PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang: note: diagnostic msg: /var/folders/xg/tgwkzqt15xd9jprnv9f0gn4c0000gn/T/CityArray-6e6c1e.m
clang: note: diagnostic msg: /var/folders/xg/tgwkzqt15xd9jprnv9f0gn4c0000gn/T/CityArray-6e6c1e.cache
clang: note: diagnostic msg: /var/folders/xg/tgwkzqt15xd9jprnv9f0gn4c0000gn/T/CityArray-6e6c1e.sh
clang: note: diagnostic msg: Crash backtrace is located in
clang: note: diagnostic msg: /Users/junhyun/Library/Logs/DiagnosticReports/clang_<YYYY-MM-DD-HHMMSS>_<hostname>.crash
clang: note: diagnostic msg: (choose the .crash file that corresponds to your crash)
clang: note: diagnostic msg: 

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Answer 1

I got this error when i was archiving my app with xcode - while running on sim and physical device worked -, but had my physical device still selected as a scheme. Solution worked for me: clean build folder, and select 'Generic IOS Device' as the scheme.