[Rd] Toolchains for x64 Windows

[Prof Brian Ripley]

The MinGW-w64 project, whose toolchains we use for 64-bit Windows, 
have made some changes to their conventions *and* removed all the 
older binary builds from their site.  The current toolchains are not 
suitable for use with R 2.11.x, and I've re-packaged an older version 
(which is) as 
http://www.stats.ox.ac.uk/pub/Rtools/oldWin64toolchain.zip

The most critical change is to no longer have an additional leading 
underscore on symbols, and we will adopt that convention for R 2.12.0. 
R-devel is now set up by default to use it: if you have been building 
R-devel with an older toolchain you will need to start afresh with the 
new one, a snapshot of which is at
http://www.stats.ox.ac.uk/pub/Rtools/Win64No_toolchain.zip

The currently recommended tools are (as ever) documented in the 
R-admin manual for the version of R you use.

Static and import libraries (but fortunately not DLLs) are 
incompatible across these changes.  Only a very few binary packages 
(e.g. Rcpp [*]) contain these, but quite a few are built using import 
libraries for external software, and either need the import libraries 
recompiled or to be converted to link directly to DLLs.  (These 
include RCurl RGtk2 cairoDevice hdf5 lossDev png rjags.)  The 
libraries we use for CRAN packages have all been recompiled: these are 
available under

old: http://www.stats.ox.ac.uk/pub/Rtools/goodies/Win64/
new: http://www.stats.ox.ac.uk/pub/Rtools/goodies/Win64No_/

Uwe Ligges does not yet have a build service for R-devel on 
win-builder: it is hoped to have such a service within the next month 
using 32/64-bit builds, the 64-bit part using the new toolchain.

Note that the underscore convention is not the only thing which has 
changed: gcc 4.5.x is used (rather than 4.4.4) and there are extensive 
changes to the headers.  Some of these also necessitate changes to 
packages.

[*] This means that if you use Rcpp the advice is to install from 
sources yourself Rcpp and any packages using it if you are using 
R-devel on Windows.

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595