Note on OpenMP & Rcpp Plugin

[coatless]

Nino,

Hope all is well. Glancing at the updated package, I think everything should now be in order for your CRAN submission.

That is, you are using an #ifdef _OPENMP to protect against including OpenMP headers ( <omp.h> ) if they are absent from the crippled compiler inside a custom myomp.h

echoice2/src/myomp.h

Line 1 in 114108d

#ifdef _OPENMP

However, the next line down, you are including:

// [[Rcpp::plugins(openmp)

This plugin only works with the standalone Rcpp functions (evalCpp(), cppFunction(), and sourceCpp()). Within a package context, it isn't setting any variables required. You can remove this line as a result.

The true compiler flags for OpenMP are being set in src/Makevars:

echoice2/src/Makevars

Lines 2 to 3 in 114108d

	PKG_CXXFLAGS = $(SHLIB_OPENMP_CXXFLAGS)
	PKG_LIBS = $(SHLIB_OPENMP_CXXFLAGS) $(LAPACK_LIBS) $(BLAS_LIBS) $(FLIBS)

In particular, note that SHLIB_OPENMP_CXXFLAGS appears twice over.

[ninohardt]

James,

thank you! I removed // [[Rcpp::plugins(openmp).
It's unfortunate that MacOS users need to invest so much effort to install and recompile the package to benefit from OpenMP support, but at least it runs.

[coatless]

@ninohardt we're slowly moving toward adding the omp.h headers into the new "Mac for Rtools" approach.

https://github.com/coatless-mac/macrtools

Right now, your users should be able to get Xcode CLI, gfortran, and an assortment of R development binaries.