[llvm-dev] Build failure

[David Spickett via llvm-dev]

I should have said how to reproduce it, add this to your cmake config:
"LLVM_USE_SANITIZER:STRING
Define the sanitizer used to build LLVM binaries and tests. Possible
values are Address, Memory, MemoryWithOrigins, Undefined, Thread,
DataFlow, and Address;Undefined. Defaults to empty string."
(https://llvm.org/docs/CMake.html)

You might be able to spot the issue by eye but it's always good to be
able to test the fix anyway.