caulier.gilles, please remember to use WikiFormatting, that the Cc field requires complete email addresses, and that it is unnecessary to Cc yourself when you are the reporter.
What version of clang do you have? Run clang -v to find out.
You've shown that you're running Xcode 4.3.3, and the Xcode command line tools from Xcode 4.5.2... you should not mismatch these versions, and if possible you should use the latest version for each, which is 4.6.3. Upgrading these may fix the problem; if so, we can blacklist the older clang you were using before.
rjvbertin, yes, port select only affects the user's own actions on the command line; it does not affect what MacPorts does when it builds ports (or, if it does, then it is a bug).
You are correct, a user cannot change the default compiler that will be used for all of MacPorts.
Users should not get in the habit of overriding configure.compiler at the command line, however it is a useful tool to try out different compilers, which can then be added to the portfile as a compiler.blacklist.
