== Compiling using MingGW-w64 for both 32-bit and 64-bit ==
[wiki:UsersWikiWinCompile Back to Compiling in Windows]

== 1. Installing Minimalist GNU for Windows-w64 (MinGW-w64) ==
The objective will be to try to use the MingGW-w64 toolchain instead of the standard MingW since it has support for both 32-bit and 64-bit compiling.
Note: We are not successful yet, but just writing down our steps as we go along.

Details of the prefixes of files can be found at [http://sourceforge.net/apps/trac/mingw-w64/wiki/download%20filename%20structure What to download]

MingW-w64 site is [http://mingw-w64.sourceforge.net]

 * If you are on 64-bit Windows download one of the binary packages from [http://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win64/Automated%20Builds/] with name
starting with '''mingw-w64-1.0-bin_i686-mingw_'''

 * If you are on 32-bit Windows download one of the binary packages from [http://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win32/Automated%20Builds/] with name starting with
'''mingw-w32-1.0-bin_i686-mingw_''' (for my purposes I used mingw-w32-1.0-bin_i686-mingw_20110328.zip)

 * Extract your respective zip into a folder called C:\mingw_w64 or c:\mingw_w32
 * Add c:\mingw_w64\bin (or c:\mingw_w32\bin) to your windows environment path variable e.g.
 
{{{
set PATH=c:\mingw_w32\bin;%PATH%
}}}


== 2. Installing Msys ==

MSys is 32-bit but you can use it with your 32-bit or 64-bit mingw-w64.  Instructions are here [http://sourceforge.net/apps/trac/mingw-w64/wiki/MSYS mingw-w64 with MSYS] and repeated
here for completeness

 *  download [http://sourceforge.net/projects/mingw-w64/files/External%20binary%20packages%20%28Win64%20hosted%29/MSYS%20%2832-bit%29/ Msys] MSYS-20110309.zip
 * Extract into a folder called C:\Msys
 * launch msys.bat
 * type

{{{
sh /postinstall/pi.sh
}}}

When prompted type in C:/mingw_w64/mingw
Once done, type logout and the console should exit.

== 3. Installing Autoconf, Automake and Libtool ==
Relaunch C:\mysy\msys.bat

Verify which versions of these you have with

autoconf --version 
etc.

If they are not newer (or you get not found) than below then download and install.
Download the source code from the GNU site and save to c:\projects

 * http://ftp.gnu.org/gnu/autoconf/autoconf-2.65.tar.gz
 * http://ftp.gnu.org/gnu/automake/automake-1.11.tar.gz
 * http://ftp.gnu.org/gnu/libtool/libtool-2.4.tar.xz


{{{
cd /c/projects
tar -xvf autoconf-2.65.tar.gz
cd autoconf-2.65
./configure --build=i686-w64-mingw32 --host=i686-w64-mingw32 (if you are building for 64-bit then use --build=x86_64-w64-mingw32)
make && make install
autoconf --version
}}}

repeat same exercise for automake

For libtool
{{{
cd /c/projects
tar -xvf libtool-2.4.10.tar.gz
cd libtool-2.4
./configure --build=i686-w64-mingw32 --host=i686-w64-mingw32 --target=i686-w64-mingw32  --disable-shared 
#if you are building for 64-bit then use --host=x86_64-w64-mingw32 for the build,host,target
make clean && make && make install
libtool --version

}}}

== 4. Compiling GEOS ==

Download latest GEOS source from http://trac.osgeo.org/geos/ either the http://download.osgeo.org/geos/geos-3.3.0.tar.bz2 or http://download.osgeo.org/geos/geos-svn.tar.bz2 and copy to c:\projects\geos.
You can also use the trunk svn version https://svn.osgeo.org/geos/trunk. If you are using svn version, make sure to run:

{{{
sh autogen.sh
}}}

{{{
cd /c/projects/geos
bzip2 -d -c geos-svn.tar.bz2 | tar xvf -
./configure --prefix=/c/projects/geos/rel-3.3.0 --build=i686-w64-mingw32 --host=i686-w64-mingw32 --target=i686-w64-mingw32
make
make install
}}}
To strip all the debug info weight from the libgeos DLL files, run
{{{
# strip /c/projects/bin/geos/rel-3.3.0/*.dll
}}}