This surfaced yesterday, when compiling test/Sema/cocoa.m on Leopard. Since this has nothing to do with ObjC, it's kind of bizarre this hasn't shown up before. I imagine Cocoa.h on Leopard may have changed recently?
Thanks to Ted for localizing the bug and giving me a useful AST dump...
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@43114 91177308-0d34-0410-b5e6-96231b3b80d8