I got this on macOS Sequoia (10.15, higher than 10.13):
saigo-release-scripts/build/shared/llvm-project/llvm/lib/Support/Unix/Path.inc:796:7:
error: 'futimens' is only available on macOS 10.13 or newer [-Werror,-Wunguarded-availability-new]
796 | if (::futimens(FD, Times))
| ^~~~~~~~~~
I got this on macOS Sequoia (10.15, higher than 10.13):