clang moved in Xcode 4.3

[Jack Howarth]

   It appears that the following change will be required for Xcode 4.3 in port's
/opt/local/share/macports/Tcl/port1.0/portconfigure.tcl due to the fact that clang/clang++
only resides in /usr/bin now....

--- portconfigure.tcl.orig	2012-02-17 21:00:58.000000000 -0500
+++ portconfigure.tcl	2012-02-17 21:01:42.000000000 -0500
@@ -422,11 +422,11 @@
         }
         clang {
             switch -exact ${type} {
-                cc   { set ret ${developer_dir}/usr/bin/clang }
-                objc { set ret ${developer_dir}/usr/bin/clang }
+                cc   { set ret /usr/bin/clang }
+                objc { set ret /usr/bin/clang }
                 cxx  {
-                    if {[file executable ${developer_dir}/usr/bin/clang++]} {
-                        set ret ${developer_dir}/usr/bin/clang++
+                    if {[file executable /usr/bin/clang++]} {
+                        set ret /usr/bin/clang++
                     } else {
                         set ret ${developer_dir}/usr/bin/llvm-g++-4.2
                     }

Note that llvm-gcc-4.2 and llvm-g++-4.2 still reside in the nested Developer/usr/bin
in Xcode.app so those are still found by port during builds.
                  Jack