C++14 standard requested but CXX14 is not defined

[bgoodri]

I would just

Having trouble when testing my RStan configuration

Just install the binaries install.packages("https://win-builder.r-project.org/yBy293t1c6Wo/StanHeaders_2.18.1-9.zip", repos = NULL) install.packages("https://win-builder.r-project.org/1R86iN7B5NYq/rstan_2.19.1.zip", repos = NULL)