OpenCV recompile with CuDNN for Win10 undeclared identifier error

I wouldn’t as it looks like you are mixing up versions of the OpenCV main and contrib repositoriess.

DIFFERENT_SIZES_EXTRA was added to the main repository in

so if you have the test cases from

but not the defines you are using a more recent commit from the contrib than the main repo.

I would rebuild from the tip of the master of both the main and contrib repositories.