If the TargetMachine isn't defined the linker will choose
the correct target depending on the input file. This helps
us later with additional compiler platforms for WinCE.
Configure a hand-generated Visual Studio project to build the compiler id
source file since we cannot run the compiler command-line tool directly.
Add a post-build command to print out the full path to the compiler tool.
Parse the full path to the compiler tool from the build output.
Configure a hand-generated Xcode project to build the compiler id source
file since we cannot run the compiler command-line tool directly. Add a
post-build shell script phase to print out the compiler toolset build
setting. Run xcodebuild to compile the identification binary. Parse
the full path to the compiler tool from the xcodebuild output.
