//typedef __int64 MPI_Offset;
typedef long long MPI_Offset;
2. Download Rmpi from http://www.stats.uwo.ca/faculty/yu/Rmpi/download/linux/Rmpi_0.5-7.tar.gz
3. Untar the source and modify src/Makevars.win by changing directory and library option (-lmsmpi) as follows:
PKG_CFLAGS = -I"C:\Program Files\Microsoft HPC Pack 2008 SDK\Include" -DMPI2 -DWin32
PKG_LIBS = -L"C:\Program Files\Microsoft HPC Pack 2008 SDK\Lib\i386" -lmsmpi
4. Compile and install
R CMD INSTALL Rmpi
5. Build for re-distribution
R CMD build --binary Rmpi