[Rd] Bundling system dependencies in binary packages

[Louis Aslett]

On 3 December 2014 at 07:40, Prof Brian Ripley wrote:
> On 02/12/2014 18:34, Louis Aslett wrote:
>> I've been hunting round for the accepted method of bundling system
>> dependencies into binary packages.
>>
>> For example, there are some CRAN packages (e.g. gmp, RcppArmadillo,
>> ...) which don't require the system dependencies be installed for the
>> Windows and Mac binary builds.  I understand that there are a very
>> limited number of packages for which CRAN would do this, so as a first
>> step I'm *not* asking how to get this on CRAN, but rather this
>> highlights there must be a (fairly automated/easy) mechanism to
>> achieve this.  Is it as simple as statically linking?  If so there's
>
> Well, packages using just C++ headers (RcppArmadillo is one) do not have
> libraries to link to.

Sorry, yes I discovered when I went to do a concrete example that I
was mistaken in thinking RcppArmadillo fell under the category of
packages I was thinking about.  gmp is the exemplar for bundling
dependencies that my query was driving at.

>
> But as far as possible the Windows and OS X binary packages are
> statically linked.  What is available to CRAN package builds is at
> http://www.stats.ox.ac.uk/pub/Rtools/libs.html
> http://r.research.att.com/libs/ (and includes gmp).
>
>> surely an automated way to trigger this without having to modify
>> Makevars to produce the static linked packages?
>>
>> The Writing R Extensions manual section on binary packages doesn't
>> mention this and I've tried extensive Googling without joy.
>
> Nothing special is needed: the linkers use static linking if there is no
> dynamic library available.  So the external software is built with
> configure options --enable-static --disable-shared .  On OS X it also
> has to be built with PIC flags (not the default for static libraries).
>

Ok, this was exactly the issue ... my GMP didn't have PIC for the
static library.  As soon as I recompiled GMP using --with-pic for the
configure script I was able to temporarily rename my dynamic library
versions of GMP and FLINT and it picked up the static libraries
without throwing any errors.

Thank you very much -- I wasn't at all aware PIC was needed for static
code on OS X!  I'd assumed I was missing something much more
elaborate.

>> So in a nut shell, I'm looking to bundle a binary version of GMP
>> (https://gmplib.org) and FLINT (http://flintlib.org) into my package
>> for Windows/Mac users who can't/won't compile the libraries and which
>> I can distribute independently of CRAN, but without having to do so in
>> a manual/hacky way by tweaking Makevars each time, or modifying the
>> tgz/zip produced by R.
>
> There are a few exceptions where dynamic linking is used on Windows, and
> the configure scripts are used to install DLLs into the libs directory.
>   (RCurl is one, currently.)  The main reason for not doing so is naming
> conflicts for DLLs on Windows. For example, if you were to have a
> gmp.dll and so did package gmp, the first loaded would win, even though
> they might be different versions (and this was common for zlib1.dll).
>

Many thanks again,

Louis