v5.3.3

A bug fix release for older compilers. Same hash values and same iteration order as 5.3.2.

• unordered_dense.h used __has_cpp_attribute(likely) without checking first that __has_cpp_attribute exists. MSVC 19.16 (Visual Studio 2017) does not have it, so it warned with C4067, which is an error with /WX. The check is now guarded with defined(__has_cpp_attribute), like the other feature checks in the headers. Compilers that have it behave the same as before (#385, thanks @thbeu!).

The inline namespace is v5_3_3.