Error. Rstan in Windows

Here’s the error I get when I run my model: Warning message:
In system(paste(CXX, ARGS), ignore.stdout = TRUE, ignore.stderr = TRUE) :
‘-E’ not found. Is this normal? I’ve just installed the new version of rstan.
The R version is 3.6.2, and the stan version is 2.21.2.

That warning does not affect anything and is safe to ignore. It’s just a misconfiguration, and will be fixed in the next RStan version