According to the Rcpp FAQ (2.15. What about the new ‘no-linking’ feature), since Rcpp version 0.11.0 we can avoid specifying LAPACK/BLAS/Fortran in a Makevars file, and in fact avoid a Makevars entirely if we follow these instructions.
... only two things are required:
• an entry in DESCRIPTION such as Imports: Rcpp (which
may be versioned as in Imports: Rcpp (>= 0.11.0)), and
• an entry in NAMESPACE to ensure Rcpp is correctly instantiated,
for example importFrom(Rcpp, evalCpp).
But instead of adding an Imports line for Rcpp, would a LinkingTo also work? That is, can I use:
LinkingTo: Rcpp (>= 0.11.0)
instead of:
Imports: Rcpp (>= 0.11.0)
Or are both needed?
In short, no -- you need both just as we say as they have different purposes.
LinkingTo: is, for all intents and purposes, a directive for R to tell the compiler where needed header files are. Packages building against Rcpp must have this.
Imports: deals with the package namespace and initialization on package load / attach. Rcpp is "almost" purely header-based but a little bit of code needs to be executed.
All this is documented for R in the Writing R Extensions manual and for Rcpp in our package vignettes.