install R on Mac OS 10.14 with openMP capable clang

install-r.sh

wget https://stat.ethz.ch/CRAN/src/base/R-3/R-3.5.1.tar.gz
tar -xvf R-3.5.1.tar.gz

cd R-3.5.1
vi config.site
# edit such that
# CC=/usr/local/clang-7/bin/clang
# OBJC=$CC
# F77=/usr/local/gcc-8.2/bin/gfortran-8
# LDFLAGS="-L/usr/local/clang-7/lib -L/usr/local/lib"
# CXX=/usr/local/clang-7/bin/clang++
# FC=$F77
# R_LD_LIBRARY_PATH=/usr/local/clang-7/lib:/usr/local/lib

./configure --prefix=/usr/local/R --enable-R-shlib \
  --enable-BLAS-shlib --enable-memory-profiling \
  --x-includes=/opt/X11/include --x-libraries=/opt/X11/lib \
  PKG_CONFIG_PATH=/opt/X11/lib/pkgconfig:/usr/local/lib/pkgconfig:/usr/lib/pkgconfig \
  DYLD_FALLBACK_LIBRARY_PATH=/usr/local/clang-7/lib:/usr/local/lib

make
sudo make install