macOS Mojave 10.14 beta 11でXcode 9.4.1のswift REPLも動かない…

$ swift -v Apple Swift version 4.1.2 (swiftlang-902.0.54 clang-902.0.39.2) Target: x86_64-apple-darwin18.0.0 /Users/norio/Applications/Xcode.app/Contents/Developer/usr/bin/lldb "--repl=-enable-objc-interop -sdk /Users/norio/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk -color-diagnostics" error: failed to launch REPL process: process exited with status -1 (unable to attach)

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