[Rd] build 32-bit R on x86_64?

[Simon Urbanek]

On Aug 9, 2011, at 9:41 PM, Dirk Eddelbuettel wrote:

> 
> On 9 August 2011 at 21:24, Simon Urbanek wrote:
> | 
> | On Aug 9, 2011, at 8:12 PM, Dirk Eddelbuettel wrote:
> | 
> | > 
> | > Hi Vinh,
> | > 
> | > On 9 August 2011 at 16:40, Vinh Nguyen wrote:
> | > | Dear R-Devel,
> | > | 
> | > | I'm using Ubuntu on an x86_64 machine and would like to have both the
> | > | 32-bit and 64-bit versions of R built from source.  By default,
> | > | following the usual build procedures yields 64 bit R.  Looking at
> | > | [these](http://cran.r-project.org/doc/manuals/R-admin.html#Sub_002darchitectures),
> | > | I thought I could build 32-bit R by executing
> | > | 
> | > | r_arch=32 ./configure
> | > | 
> | > | and building R like usual (make).  However, after seeing this error message,
> | > | 
> | > | /usr/bin/install: cannot create regular file
> | > | `../../include/32/Rconfig.h': No such file or directory
> | > | 
> | > | I realize I am misunderstanding the instructions.  Could someone
> | > | please clarify how I could go about compiling both 32-bit and 64-bit
> | > | versions of R on my Linux machine?  Thank you!
> | > 
> | > I do not think that multiarch build (ie 32 and 64 at the same time) are fully supported yet on Ubuntu or Debian. It is coming, but just like a number of other things, not exactly overnight. It is a release goal.
> | > 
> | 
> | It actually works ;) I'm using it for testing on my RForge.net machine and yes, it's Debian - everything just works there :).
> | 
> | But back to the original question. First a minor detail, don't set environment variables use configure variables instead. Second, don't build in the source directory, always create an object directory. Third, r_arch is simply a name you set for the architecture, it has no meaning other than that it's a label.
> | 
> | So now to the real stuff. If you want 32-bit build, you'll need 32-bit runtime of everything important in your system and the multilib compilers. In Debian (and thus likely in Ubuntu too) that can be achieved by something like
> | 
> | sudo apt-get install  ia32-libs-dev lib32readline6-dev lib32ncurses5-dev lib32icu-dev gcc-multilib gfortran-multilib
> 
> Nice one :)  
> 
> I had these installed but was always under the impression that we'd lack
> things like jpeg, png, ... libs.  So it all works as R has 'enough batteries'
> included?  Good to know ...

Yes, it's enough to build, but obviously it's like having one AAA battery installed ;)


> | 
> | Then you can build both 64-bit and 32-bit R, the difference will be in the all compiler flags -- for 64-bit you'll use -m64 (or nothing since it's the default) and for 32-bit you'll use -m32.
> | 
> | So roughly something like
> | 
> | tar fxz R-2.13.1.tar.gz
> | mkdir obj-32
> | cd obj-32
> | ../R-2.13.1/configure r_arch=i386 CC='gcc -std=gnu99 -m32' CXX='g++ -m32' FC='gfortran -m32' F77='gfortran -m32' 
> | make -j24 && sudo make install rhome=/usr/local/R/2.13
> | cd ..
> | mkdir obj-64
> | cd obj-64
> | ../R-2.13.1/configure r_arch=amd64
> | make -j24 && sudo make install rhome=/usr/local/R/2.13
> | 
> | That will leave you with multi-arch R that you can run with
> | R --arch=i386 # 32-bit
> | R --arch=amd64 # 64-bit
> | Packages will be also built as multi-libs. Good luck :)
> | [BTW the rhome=... setting is entirely optional, I just like to keep my R versions organized…]
> 
> I shall keep that for the day I'll have to start supporting multiarch in all
> the r-cran-* packages :)
> 

Well, I did give it a shot for RForge.net but the list of ia32 libraries is a bit short compared to what's available in a full 32-bit system. Obviously you can get far with using native i386 packages, but then you won't be able to take advantage of all the magic of dpkg. So I don't think you'll need to worry about multiarch R r-cran* packages too soon ;). I'm keeping multiarch R around for testing of packages since it's a pretty good test of badly written package configuration, but I would not use it for production ... (it's bad enough that I need to worry about it on OS X ;)).

Cheers,
Simon



> Thanks for waving the cluebat.
> 
> Dirk
> 
> | 
> | Cheers,
> | Simon
> | 
> | 
> | 
> | > In the meantime, you can always use virtualization. I have a Debian 32-bit
> | > system and an Ubuntu 32-bit system in KVM virtualization on my Ubuntu 64-bit
> | > server.  That works well.  Kvm, or Xen, or Virtualbox, or Vmware, ... all
> | > offer fairly decent virtualization.  
> | > 
> | > Debian/Ubuntu specific questions are even more welcome on r-sig-debian.
> | > 
> | > Dirk
> | > 
> | > -- 
> | > Two new Rcpp classes scheduled for New York and San Francisco, details at
> | > http://dirk.eddelbuettel.com/blog/2011/08/04#rcpp_classes_2011-09_and_2011-10
> | > 
> | > ______________________________________________
> | > R-devel at r-project.org mailing list
> | > https://stat.ethz.ch/mailman/listinfo/r-devel
> | > 
> | > 
> | 
> 
> -- 
> Two new Rcpp classes scheduled for New York and San Francisco, details at
> http://dirk.eddelbuettel.com/blog/2011/08/04#rcpp_classes_2011-09_and_2011-10
> 
>