The build seems to be broken since build number 4485: http://lab.llvm.org:8011/builders/clang-x64-ninja-win7/builds/4485
This is affecting the windows LLDB builders as well: http://lab.llvm.org:8011/builders/lldb-x86-windows-msvc/builds/9570
I checked with echristo offline and he is “pretty certain” that his CLs are not to blame. Hence, r246465 and r246466 in llvm seem like the culprits. Any help fixing the build will be much appreciated.