Rstan::expose_stan_function on R4.4.0 / Rstan2.32.6 / rcpp 1.0.13

Interfaces RStan
,
1

expose_stan_function ends up with message:

Error in expose_stan_functions("NormRNG.stan", show_compiler_warnings = T) : 
  Compilation failed!

stan file “NormRNG.stan”

// This Stan defines a random normal number generator
 functions {
    real standard_normal_rng() {
      return normal_rng(0,1);
   }
  }

Code for exposing:

sink("stan_model_compilation_log.txt")
expose_stan_functions("NormRNG.stan", show_compiler_warnings=T)
sink()

I tried to force C14++ but probably i have insufficient expertise.
I tried:

# Create .R directory if it doesn't exist
dotR <- file.path(Sys.getenv("HOME"), ".R")
if (!file.exists(dotR)) dir.create(dotR)

# Create or edit Makevars.win file
makevars_path <- file.path(dotR, "Makevars.win")
if (!file.exists(makevars_path)) file.create(makevars_path)

# Add C++14 compiler flag
cat("CXX14 = g++ -std=c++1y\n", file = makevars_path, append = TRUE)

# Verify the configuration
readLines(makevars_path)

Output:

[1] "CXX14 = g++ -std=c++1y"

Then:

# Check the compiler flags
system("R CMD config CXX14")
Sys.setenv(R_MAKEVARS_USER = normalizePath("~/.R/Makevars.win"))

Still error.

Also first part of the sink if relevant:

using C++ compiler: 'G__~1.EXE (GCC) 13.2.0'
using C++17
g++  -std=gnu++17 -I"C:/PROGRA~1/R/R-44~1.0/include" -DNDEBUG   -I"D:/_R/win_libary/4.0/Rcpp/include/"  -I"D:/_R/win_libary/4.0/RcppEigen/include/"  -I"D:/_R/win_libary/4.0/RcppEigen/include/unsupported"  -I"D:/_R/win_libary/4.0/BH/include" -I"D:/_R/win_libary/4.0/StanHeaders/include/src/"  -I"D:/_R/win_libary/4.0/StanHeaders/include/"  -I"D:/_R/win_libary/4.0/RcppParallel/include/" -DRCPP_PARALLEL_USE_TBB=1 -I"D:/_R/win_libary/4.0/rstan/include" -DEIGEN_NO_DEBUG  -DBOOST_DISABLE_ASSERTS  -DBOOST_PENDING_INTEGER_LOG2_HPP  -DSTAN_THREADS  -DUSE_STANC3 -DSTRICT_R_HEADERS  -DBOOST_PHOENIX_NO_VARIADIC_EXPRESSION  -D_HAS_AUTO_PTR_ETC=0  -include "D:/_R/win_libary/4.0/StanHeaders/include/stan/math/prim/fun/Eigen.hpp"  -std=c++1y  -I"D:/_R/win_libary/4.0/Rcpp/include" -I"D:/_R/win_libary/4.0/StanHeaders/include" -I"D:/_R/win_libary/4.0/rstan/include" -I"D:/_R/win_libary/4.0/RcppEigen/include" -I"D:/_R/win_libary/4.0/BH/include" -I"C:/Users/censoreduser/AppData/Local/Temp/RtmpWGUQ9y/sourceCpp-x86_64-w64-mingw32-1.0.13.1"   -I"c:/rtools44/x86_64-w64-mingw32.static.posix/include"     -O2 -Wall  -mfpmath=sse -msse2 -mstackrealign  -c file1628386e5dc2.cpp -o file1628386e5dc2.o

Versions in use:
Rcpp 1.0.13-1
RcppEigen 0.3.4.0.2
BH 1.84.0-0
StanHeaders 2.32.10
RcppParallel 5.1.9

Any suggestions?

2

H, @notasutdent and welcome to the Stan forums. And thanks for the careful bug report.

There are special requirements for calling _rng functions with expose_stan_functions but I don’t know what would cause them to not compile here. @bgoodri may know.

Can you expose a simpler function without an RNG? Say by replacing the return with just something like return 1.0;?