etc: add the `in` keyword to the emacs mode.
trans_arg_expr: Omit extra copies for rvalues

rvalues aren't going to be used anywhere but as the argument, so
there's no point in copying them. LLVM used to eliminate the copy
later, but why bother emitting it in the first place?
auto merge of #8262 : dotdash/rust/no_rval_copies, r=pcwalton

rvalues aren't going to be used anywhere but as the argument, so
there's no point in copying them. LLVM used to eliminate the copy
later, but why bother emitting it in the first place?
Try to fix a periodic windows build failure due to broken rwildcard macro
Update LLVM
Fix build issues once LLVM has been upgraded

* LLVM now has a C interface to LLVMBuildAtomicRMW
* The exception handling support for the JIT seems to have been dropped
* Various interfaces have been added or headers have changed
Fix setting the fixed stack segment attribute on LLVM functions

At the same time create a more robust wrapper to try to prevent this type of
issue from cropping up in the future.
Add a workaround for 8199 for now
Integrate new arm patch and fix an LLVM bug

Thanks @luqama!
Merge pull request #8284 from huonw/emacs-in-kw

etc: add the `in` keyword to the emacs mode.
auto merge of #7115 : alexcrichton/rust/llvm-upgrades, r=thestinger

This is a reopening of #6713

This is still blocked on windows failures. I'll re-push try once the existing crisis has passed.