Build for MacOS10.14.2 / Xcode 10.1 fails

I am trying to get a working build in xcode. I followed the instructions on GitHub - apple/swift: The Swift Programming Language I've run utils/build-script --release-debuginfo --xcode, then opened ${SWIFT_BUILD_DIR}/Swift.xcodeproj. When I try to build, I get the following error:

Ld /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/bin/swift normal x86_64
    cd /Users/bubulkowanorka/projects/swift-source/swift
    export MACOSX_DEPLOYMENT_TARGET=10.14
    /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -arch x86_64 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk -L/Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/bin -L/Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/Debug -L/Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib -F/Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/bin -filelist /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/tools/driver/Swift.build/Debug/swift.build/Objects-normal/x86_64/swift.LinkFileList -Xlinker -rpath -Xlinker /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib -mmacosx-version-min=10.14 -Xlinker -object_path_lto -Xlinker /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/tools/driver/Swift.build/Debug/swift.build/Objects-normal/x86_64/swift_lto.o -stdlib=libc++ -L/Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/swift/macosx -target x86_64-apple-macosx10.9 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk -arch x86_64 -F /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk/../../../Developer/Library/Frameworks -mmacosx-version-min=10.9 -Xlinker -rpath -Xlinker @executable_path/../lib/swift/macosx -Wl,-search_paths_first -Wl,-headerpad_max_install_names /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftDriver.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftFrontendTool.a -ledit /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftTBDGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftImmediate.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftIRGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftLLVMPasses.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangCodeGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangAST.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMMCJIT.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMExecutionEngine.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMRuntimeDyld.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftPrintAsObjC.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftIDE.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftFrontend.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftMigrator.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftIDE.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftFrontend.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftMigrator.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftIndex.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftOption.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftSILGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftSILOptimizer.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftParseSIL.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftSIL.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftSema.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftSerialization.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftClangImporter.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftDWARFImporter.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftParse.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftAST.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftBasic.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftDemangling.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftMarkup.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/cmark-macosx-x86_64/src/Debug/libcmark.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMDebugInfoDWARF.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMX86CodeGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMX86AsmParser.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMX86Desc.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMX86AsmPrinter.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMX86Disassembler.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMX86Info.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMX86Utils.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMARMCodeGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMARMAsmParser.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMARMDisassembler.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMARMDesc.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMARMAsmPrinter.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMARMInfo.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMARMUtils.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMAArch64CodeGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMAArch64AsmParser.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMAArch64Disassembler.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMAArch64Desc.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMAArch64AsmPrinter.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMAArch64Info.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMAArch64Utils.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMPowerPCCodeGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMPowerPCAsmParser.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMPowerPCDesc.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMPowerPCAsmPrinter.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMPowerPCDisassembler.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMPowerPCInfo.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMSystemZCodeGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMSystemZAsmParser.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMSystemZDisassembler.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMSystemZDesc.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMSystemZAsmPrinter.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMSystemZInfo.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMMipsCodeGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMAsmPrinter.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMGlobalISel.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMSelectionDAG.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMMipsAsmParser.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMMipsDesc.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMMipsAsmPrinter.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMMipsDisassembler.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMMCDisassembler.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMMipsInfo.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangFrontendTool.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangCodeGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMCoroutines.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMCoverage.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMLTO.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMObjCARCOpts.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMPasses.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMipo.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMIRReader.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMAsmParser.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMInstrumentation.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMLinker.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMCodeGen.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMBitWriter.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMScalarOpts.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMAggressiveInstCombine.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMInstCombine.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMVectorize.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMTransformUtils.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMTarget.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMAnalysis.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMObject.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangARCMigrate.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangStaticAnalyzerFrontend.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangStaticAnalyzerCheckers.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangStaticAnalyzerCore.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangCrossTU.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangIndex.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangFormat.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangToolingInclusions.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangToolingCore.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangASTMatchers.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangRewriteFrontend.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangFrontend.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMProfileData.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangDriver.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMOption.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangParse.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMMCParser.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangSerialization.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangSema.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangAnalysis.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangEdit.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangRewrite.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangAST.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangLex.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangAPINotes.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMBitReader.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangBasic.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMMC.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMDebugInfoCodeView.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMDebugInfoMSF.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMCore.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMBinaryFormat.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMSupport.a -lz -lcurses -lm /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libLLVMDemangle.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/lib/libswiftSyntax.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangAPINotes.a /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/llvm-macosx-x86_64/RelWithDebInfo/lib/libclangBasic.a -Xlinker -dependency_info -Xlinker /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/tools/driver/Swift.build/Debug/swift.build/Objects-normal/x86_64/swift_dependency_info.dat -o /Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/swift-macosx-x86_64/Debug/bin/swift

clang: error: no such file or directory: '/Users/bubulkowanorka/projects/swift-source/build/Xcode-RelWithDebInfoAssert/cmark-macosx-x86_64/src/Debug/libcmark.a'

I checked out the master branch.

Is it a known issue? Is anyone able to help?

Not sure if you've managed to fix the issue, but you need to open the CMark Xcode project (in cmark-macosx-x86_64) and build it. After that, go back to the Swift project and try building it again - it should be fine.

Works for me after building cmark project. Not sure why but i followed all the steps in the doc