Attempting to compile an Objective-C++ source file suffixed “.mm” results in an error complaining about the file extension being unrecognized.

Patch looks good to me, and back porting to 3.6/3.7 should be safe enough.

I haven't merged yet because I need to study the devguid a bit before I do so (especially w.r.t. back porting)

In short:

- Approve the PR (the bots will remove label «core review needed» and add «waiting for merge»

- Do not add «backport» labels as this is a new feature

- Push the squash and merge button
  - edit the commit message first line to have GH-123 instead of #123
  - edit the pre-filled commit message body to something better

- Watch CI on the master branch then buildbots

Eric,

Thanks. 

See the pull request for why this might qualify for a back port: other parts of distutils recognise '.mm' as a valid extension, but '.mm' doesn't work yet because UnixCCompiler doesn't support this yet. 

On the other hand this is effectively a new feature because '.mm' has never worked, and there is an easy workaround (monkey patching the compiler class).

And writing this I agree that this patch should not be back ported.

Distutils is now deprecated (see PEP 632) and all tagged issues are being closed. From now until removal, only release blocking issues will be considered for distutils.

If this issue does not relate to distutils, please remove the component and reopen it. If you believe it still requires a fix, most likely the issue should be re-reported at https://github.com/pypa/setuptools