Add rudimentary support for the Apple Swift language with Xcode

Allow the `Swift` language to be enabled with the Xcode generator for
Xcode >= 6.1.  Reject it on other generators and with older Xcode
versions.  Since Apple is the only vendor implementing the language
right now, the compiler id can be just `Apple`.

1 files changed, 4 insertions, 0 deletions

diff --git a/Source/cmGlobalXCodeGenerator.cxx b/Source/cmGlobalXCodeGenerator.cxx
index 505929e..21075bb 100644
--- a/Source/cmGlobalXCodeGenerator.cxx
+++ b/Source/cmGlobalXCodeGenerator.cxx
@@ -843,6 +843,10 @@ GetSourcecodeValueFromFileExtension(const std::string& _ext,
     {
     sourcecode += ".c.objc";
     }
+  else if (ext == "swift")
+    {
+    sourcecode += ".swift";
+    }
   else if(ext == "plist")
     {
     sourcecode += ".text.plist";