Created attachment 605780 [details] [diff] [review]
It seems to be undocumented, but winnt.h contains macro which defines RotateLeft32 to _rotl. It's a macro, so mozilla namespace doesn't help and if winnt.h is included before HashFunctions.h, it gets replaced. It does not yet cause compilation errors on MSVC (it does on mingw), but it's surely something we should avoid. My proposed patch renames the function to RotateBitsLeft32.
Thanks for the review.