/Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2016-02-08-a.xctoolchain/usr/bin/swiftc --driver-mode=swift -I /Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2016-02-08-a.xctoolchain/usr/lib/swift/pm -L /Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2016-02-08-a.xctoolchain/usr/lib/swift/pm -lPackageDescription -target x86_64-apple-macosx10.10 /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/Package.swift
/usr/bin/xcrun --sdk macosx --show-sdk-path
/Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2016-02-08-a.xctoolchain/usr/bin/swift-build-tool -v -f /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/.build/debug/swiftygpio.o/llbuild.yaml
/Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2016-02-08-a.xctoolchain/usr/bin/swiftc -module-name swiftygpio -incremental -emit-dependencies -emit-module -emit-module-path /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/.build/debug/swiftygpio.swiftmodule -output-file-map /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/.build/debug/swiftygpio.o/swiftygpio/output-file-map.json -parse-as-library -c /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/Sources/SwiftyGPIO.swift -I /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/.build/debug -j8 -Onone -g -v -target x86_64-apple-macosx10.10 -enable-testing -sdk /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk -I /usr/local/include -D SWIFT_PACKAGE
Apple Swift version 3.0-dev (LLVM a7663bb722, Clang 4ca3c7fa28, Swift 1c2f40e246)
Target: x86_64-apple-macosx10.10
/Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2016-02-08-a.xctoolchain/usr/bin/swift -frontend -c -primary-file /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/Sources/SwiftyGPIO.swift -target x86_64-apple-macosx10.10 -enable-objc-interop -sdk /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk -I /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/.build/debug -I /usr/local/include -enable-testing -g -D SWIFT_PACKAGE -emit-module-doc-path /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/.build/debug/swiftygpio.o/swiftygpio/SwiftyGPIO~partial.swiftdoc -Onone -parse-as-library -module-name swiftygpio -emit-module-path /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/.build/debug/swiftygpio.o/swiftygpio/SwiftyGPIO~partial.swiftmodule -emit-dependencies-path /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/.build/debug/swiftygpio.o/swiftygpio/SwiftyGPIO.d -emit-reference-dependencies-path /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/.build/debug/swiftygpio.o/swiftygpio/SwiftyGPIO.swiftdeps -o /Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/.build/debug/swiftygpio.o/Sources/SwiftyGPIO.swift.o
/Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/Sources/SwiftyGPIO.swift:192:46: error: use of unresolved identifier 'O_SYNC'
        let mem_fd = open("/dev/mem", O_RDWR|O_SYNC)
                                             ^~~~~~
<unknown>:0: error: build had 1 command failures
swift-build: error: exit(1): ["/Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2016-02-08-a.xctoolchain/usr/bin/swift-build-tool", "-v", "-f", "/Users/USER/Developer/swiftweb/Clones/SwiftyGPIO/.build/debug/swiftygpio.o/llbuild.yaml"]