SDK "iphoneos" cannot be located

在MAC下，交叉編譯libvlc出現的一些問題和解決方法。
項目中使用了libvlc開源庫。
在執行編譯腳本中，遇到一句xcrun --sdk iphoneos --show-sdk-path報錯

mac$ xcrun --sdk iphoneos --show-sdk-path
xcrun: error: SDK "iphoneos" cannot be located

查找緣由：

mac$ xcode-select --print-path
/Library/Developer/CommandLineTools

發現是這個Xcode路徑判斷錯誤。

mac$ xcodebuild -showsdks
xcode-select: error: tool 'xcodebuild' requires Xcode, but active developer directory '/Library/Developer/CommandLineTools' is a command line tools instance

回想起最近安裝了另外兩個版本的Xcode，應該是這樣致使了路徑錯誤。

mac$ ls /Applications/Xcode
Xcode.app/ Xcode2.app/ Xcode3.app/

解決方法：給Xcode命令行工具指定路徑

mac$ sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer/

再回頭查看

mac$ xcrun --sdk iphoneos --show-sdk-path
2016-04-27 14:21:06.359 xcodebuild[88326:4628314] [MT] DVTSDK: Warning: SDK path collision for path '<DVTFilePath:0x7f8012844eb0:'/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS8.1.sdk'>': SDK with name 'iphoneos8.1' being superceded by SDK with 'iphoneos8.1'.
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS8.0.sdk
mac$ xcodebuild -showsdks
2016-04-27 14:24:26.543 xcodebuild[88334:4629525] [MT] DVTSDK: Warning: SDK path collision for path '<DVTFilePath:0x7f8cd15e4f50:'/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS8.1.sdk'>': SDK with name 'iphoneos8.1' being superceded by SDK with 'iphoneos8.1'.
OS X SDKs:
OS X 10.9 -sdk macosx10.9
OS X 10.10 -sdk macosx10.10

iOS SDKs:
iOS 8.1 -sdk iphoneos8.1

iOS Simulator SDKs:
Simulator - iOS 8.1 -sdk iphonesimulator8.1

 

參考 http://www.ithao123.cn/content-10811313.html 特此感謝
目前編譯libvlc的MAX機其餘軟件環境以下

mac$ sw_vers
ProductName:    Mac OS X
ProductVersion:    10.10.5
BuildVersion:    14F27
mac$ uname -a
Darwin xxx.local 14.5.0 Darwin Kernel Version 14.5.0: Wed Jul 29 02:26:53 PDT 2015; root:xnu-2782.40.9~1/RELEASE_X86_64 x86_64