Compilation flags for RcppParallel

Output the compiler or linker flags required to build against RcppParallel.

Usage

CxxFlags()

LdFlags()

RcppParallelLibs()

Value

Returns NULL, invisibly. These functions are called for their side effects (writing the associated flags to stdout).

Details

These functions are typically called from Makevars as follows:

PKG_LIBS += $(shell "${R_HOME}/bin/Rscript" -e "RcppParallel::LdFlags()")

What is emitted depends on how TBB is resolved at runtime on each platform. On Windows, every symbol has to be resolved at link time, so the flags name both the TBB libraries RcppParallel ships and RcppParallel itself. On macOS, they name the TBB libraries along with an -rpath entry, so that the resulting binary can find them without relying on RcppParallel having been loaded first. On Linux, the output is empty: TBB symbols are left undefined at link time and resolved from the libraries RcppParallel loads.

R packages using RcppParallel should also add the following to their NAMESPACE file:

importFrom(RcppParallel, RcppParallelLibs)

This is necessary to ensure that RcppParallel (and so, TBB) is loaded and available.