CMake fails to generate iOS Xcode project (tried both Xcode 7 and 8)

cmake -G Xcode -DCMAKE_OSX_SYSROOT=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS9.3.sdk ../ Fails with:

-- The C compiler identification is AppleClang 7.3.0.7030031
-- The CXX compiler identification is AppleClang 7.3.0.7030031
-- Check for working C compiler: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang
-- Check for working C compiler: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -- broken
CMake Error at /Applications/CMake.app/Contents/share/cmake-3.6/Modules/CMakeTestCCompiler.cmake:61 (message):
  The C compiler
  "/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang"
  is not able to compile a simple test program.

  It fails with the following output:

   Change Dir: /Users/Administrator/projects/dlib/build/CMakeFiles/CMakeTmp

  

  Run Build Command:"/usr/bin/xcodebuild" "-project"
  "CMAKE_TRY_COMPILE.xcodeproj" "build" "-target" "cmTC_a198d"
  "-configuration" "Debug"

  === BUILD TARGET cmTC_a198d OF PROJECT CMAKE_TRY_COMPILE WITH CONFIGURATION
  Debug ===

  

  Check dependencies

  target specifies product type 'com.apple.product-type.tool', but there's no
  such product type for the 'iphoneos' platform

  

  ** BUILD FAILED **

  

  

  The following build commands failed:

      Check dependencies

  (1 failure)

  

  

  CMake will not be able to correctly generate this project.
Call Stack (most recent call first):
  CMakeLists.txt

CMakeError.log: http://pastebin.com/raw/EaAF3pj4 CMakeOutput.log: http://pastebin.com/raw/at8rANWJ