I am trying to build an R package which includes Rcpp and RcppArmadillo code. sourceCpp() works fine and everything runs smoothly, but when I try to build the package I get: "This file requires compiler and library support for the
ISO C++ 2011 standard. This support is currently experimental, and must be
enabled with the -std=c++11 or -std=gnu++11 compiler options."

Including RcppArmadillo and Rcpp11 in the description file does not seem to help (see below)

My description file includes:

```
Imports:
  Rcpp (>= 0.12.13),
  RcppArmadillo (>= 0.7.900.2.0),
  Rcpp11 (>=    3.1.1.0),
  data.table
LinkingTo: Rcpp, RcppArmadillo, Rcpp11

```

I've not included the two .cpp files as they are fairly long, but obviously the issue seems to be the use of C++11 syntax.