OS X no longer reports upstream LLVM version

Starting with OS X El Capitan, the output of clang --version is similar to:

Apple LLVM version 7.0.0 (clang-700.0.53)
Target: x86_64-apple-darwin15.0.0
Thread model: posix

This means, going forward, that the logic at

rust/configure

Line 974 in 3d74fbd

CFG_CLANG_VERSION=$($CFG_CC \

can no longer accurately determine what version of clang is running on OS X.

Before El Capitan's beta I would have suggested having pairs of Apple Clang versions and their upstream counterparts to compare to (i.e. using a resource such as https://gist.github.com/yamaya/2924292) but I imagine the new --version output is Apple subtly suggesting applications shouldn't need to know what version of LLVM is under the hood.

[nagisa]

Apple subtly suggesting applications shouldn't need to know what version of LLVM is under the hood.

We are not an application, we are a compiler. Since they do not want us to, anymore, I guess the only way is to go ahead and ship our own set of LLVM tools (we currently do not).

[polidore]

any safe workaround?

[nagisa]

#27006 was merged, therefore it should work.

[steveklabnik]

closing, thanks @nagisa