I was wrong. It is still crashing in my larger files with this:
Unhandled exception at 0x00007FFBEB93B550 (CppEngineCore64.DLL) in CppEngineHost64.exe.25180.dmp: 0xC0000005: Access violation reading location 0x0000000000000000. occurred
It looks like some specific part of your code is triggering a bug in Clang (it fails to resolve an incomplete template). The easiest way to fix this would be if you could narrow it down to a specific combination of headers and send them to us along with the repro instructions. If this is not possible, we can send you a special diagnostic build of the Clang engine that will help us pinpoint and fix the problem based on the crash dump.