b7bca8663a
The issue was caused by the fact that in this version of MSVC unordered_map class is defined in <unordered_map> header file, but this file declares the class int std::tr1 namespace. This confused existing assumption that if there's an existing <unordered_map> file then class is declared in std namespace. Added an extra check to CMake which detects whether it's std or std::tr1 which actually contains class of unordered_map. This might be changed/cleaned in the future, for now committing to our repository to solve compilation error on windows. Details of the patch in upstream can be found there: https://ceres-solver-review.googlesource.com/#/c/4371/