R 4.0, rstan, and you

[torkar]

Hi,

the example you gave compiles and samples for me. I have latest R, RStudio, Xcode, and rstan 2.26.0.9000. Running with latest cmdstan/r also works:

All 4 chains finished successfully.
Mean chain execution time: 0.0 seconds.
Total execution time: 0.6 seconds.
 variable  mean median   sd  mad    q5   q95 rhat ess_bulk ess_tail
     lp__ -1.46  -1.14 1.20 0.97 -3.84 -0.18 1.00     1505     1668
     y[1] -0.01  -0.01 1.00 1.00 -1.64  1.62 1.00     1710     1896
     y[2] -0.03  -0.02 2.72 2.02 -4.54  4.37 1.00     2056     1564

[jroon]

As the github issues suggested @rok_cesnovar I reinstalled rstan dev version and now the error message changed slightly:

Any ideas? I thought I removed Makevars and Environment files - something else lurking that needs to go?

Edit: I found a Github issue relating to this and added my details: Warning - 'config' variable 'CPP' is deprecated · Issue #862 · stan-dev/rstan · GitHub