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+Compiling rql for Windows
+=========================
+
+
+RQL can use either logilab.constraint or gecode to perform type
+inference. This document explains how the gecode support can be added
+for the Windows platform. 
+
+The short way
+-------------
+
+Download and install http://ftp.logilab.org/pub/rql/XXX
+
+The long way
+------------
+
+Problem statement: we want to use python2.5 on windows. Compiling C
+extensions requires Visual Studio 2003, but Gecode requires Visual
+Studio 2008. So we are stuck with using MinGW, and then again Gecode
+requires gcc 4.2 or later and cygwin to support building. 
+But cygwin doesn't come with a mingw enabled gcc 4.x (only 3.x
+available), so some stiching is required. 
+
+Dependencies installation
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+* cygwin_: download http://www.cygwin.com/setup.exe, run it and select the following
+  packages:
+
+  - diffutils
+  - perl
+  - g++-mingw
+  - some text editor of your choice (nano, vim...)
+
+* mingw: download the following files:
+
+  - `gcc-g++-4.4.0-bin <http://sourceforge.net/projects/mingw/files/GCC%20Version%204/Current%20Release_%20gcc-4.4.0/gcc-c%2B%2B-4.4.0-mingw32-bin.tar.gz/download>`
+
+  - `gcc-g++-4.4.0-dll <http://sourceforge.net/projects/mingw/files/GCC%20Version%204/Current%20Release_%20gcc-4.4.0/gcc-c%2B%2B-4.4.0-mingw32-dll.tar.gz/download>`
+
+  - `gcc-core-4.4.0-bin <http://sourceforge.net/projects/mingw/files/GCC%20Version%204/Current%20Release_%20gcc-4.4.0/gcc-core-4.4.0-mingw32-bin.tar.gz/download>`
+
+  - `gcc-core-4.4.0-dll <http://sourceforge.net/projects/mingw/files/GCC%20Version%204/Current%20Release_%20gcc-4.4.0/gcc-core-4.4.0-mingw32-dll.tar.gz/download>`
+
+ - `gmp-4.2.4-dll <http://sourceforge.net/projects/mingw/files/GCC%20Version%204/Current%20Release_%20gcc-4.4.0/gmp-4.2.4-mingw32-dll.tar.gz/download>`
+
+ - `mpfr-2.4.1-dll <http://sourceforge.net/projects/mingw/files/GCC%20Version%204/Current%20Release_%20gcc-4.4.0/mpfr-2.4.1-mingw32-dll.tar.gz/download>`
+
+ - `binutils-2.19.1-bin <http://sourceforge.net/projects/mingw/files/GNU%20Binutils/Current%20Release_%20GNU%20binutils-2.19.1/binutils-2.19.1-mingw32-bin.tar.gz/download>`
+
+ - `w32api-3.13-dev <http://sourceforge.net/projects/mingw/files/MinGW%20API%20for%20MS-Windows/Current%20Release_%20w32api-3.13/w32api-3.13-mingw32-dev.tar.gz/download>`
+
+  - `mingwrt-3.15.2-dev <http://sourceforge.net/projects/mingw/files/MinGW%20Runtime/mingwrt-3.15.2/mingwrt-3.15.2-mingw32-dev.tar.gz/download>`
+
+  - `pthreads-2.8.0-dll
+    <http://sourceforge.net/projects/mingw/files/GCC%20Version%204/Current%20Release_%20gcc-4.4.0/pthreads-w32-2.8.0-mingw32-dll.tar.gz/download>`
+    NON!!!! ne pas installer ça pête tout 
+
+  - XXX FIXME add missing build deps
+
+
+Create c:\MinGW. Launch a cygwin shell, go to /cygdrive/c/MinGW and
+untar all the mingw tarballs
+
+Edit /etc/profile and go to the place where the PATH environment
+variable is set. Change the line to *prepend*
+/cygdrive/c/MinGW/bin:/cygdrive/c/MinGW/libexec/mingw32/4.4.0 to the PATH
+
+* download and untar Gecode 3.1.0 source distribution from
+  http://www.gecode.org/download/gecode-3.1.0.tar.gz
+
+
+Compiling gecode
+~~~~~~~~~~~~~~~~
+
+In a cygwin shell, go the the untarred Gecode source directory and run::
+
+  $ ./configure --enable-version-specific-runtime-libs \
+                --disable-shared --disable-qt --disable-gist \
+                --disable-examples --enable-static
+
+Edit gecode/support/config.hpp, and change the line ::
+
+  #define GECODE_USE_GETTIMEOFDAY 1
+
+to::
+
+  #define GECODE_USE_CLOCK 1
+
+run::
+
+  $ make
+
+and be patient 
+
+
+Compiling the C extension in rql
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+in a Windows shell (aka "DOS Console"), go the the rql directory and
+run::
+
+$ python setup.py build_ext -c mingw32 \
+                            -Ic:\temp\gecode-3.1.0 \
+                            -Lc:\temp\gecode-3.1.0 
+
+You're done.