Sam,
PS It could of course also be something else: Is you src/Makevars for your
test package correct? Did you use `RcppArmadillo.packages.skeleton()` ? You
need the lapack/blas link instruction therein. See
edd at rob:~$ cat /usr/local/lib/R/site-library/RcppArmadillo/skeleton/Makevars
## With R 3.1.0 or later, you can uncomment the following line to tell R to
## enable compilation with C++11 (where available)
##
## Also, OpenMP support in Armadillo prefers C++11 support. However, for wider
## availability of the package we do not yet enforce this here. It is however
## recommended for client packages to set it.
##
## And with R 3.4.0, and RcppArmadillo 0.7.960.*, we turn C++11 on as OpenMP
## support within Armadillo prefers / requires it
CXX_STD = CXX11
PKG_CXXFLAGS = $(SHLIB_OPENMP_CXXFLAGS)
PKG_LIBS = $(SHLIB_OPENMP_CXXFLAGS) $(LAPACK_LIBS) $(BLAS_LIBS) $(FLIBS)
edd at rob:~$
Dirk