tools-make/Documentation/README.MinGWOnCygwin

Cross Compiling GNUstep for MinGW from Cygwin
=============================================

If you wish to build on a native MinGW system (recommended),
please read README.MinGW instead.

MinGW is a collection of header files and import libraries that allow
one to use GCC and produce native Windows32 programs that do not rely
on any 3rd-party DLLs. GNUstep has only partially been ported to MinGW
so expect some problems when trying to compile. Also, there are still
subtle problems with running GNU tools on Windows, so any problems you
may encounter may just as easly have to do with the compilation tools
you are using as with GNUstep.

The base library is not completely ported to run on MinGW yet, but most
stuff works, including networking/distributed objects.
Probably background file handle operations (other than networking) and
advanced parts of NSTask code do not currently work.

Note for compiling with shared libraries (DLLs), it's a good idea to
remove the libobjc.a that comes with gcc (gcc -v for location) so that
it isn't accidentally found instead of the libobjc DLL that you will
compile below. Also note that, despite the statement in the GNUstep-HOWTO,
even if you have 3.x, you still need to install gnustep-objc as it properly 
exports symbols for DLLs.

Note also that the //c construct for specifying paths with drives has
been depreciated. You'll need to use /cygwin/path or C: style paths now.

MinGW on Cygwin
---------------

Not recommended. This is a cross compilation solution. Using native
mingw/msys is simpler and less error prone.

Uses the Cygwin tools to help out with the configuration and compilation of
the libraries. It's always good to get the very latest version of
Cygwin and MinGW. These instructions were performed
with Cygwin DLL 1.3.9-1 and MingW gcc 2.95.3-6. If you have more
experience with MinGW than me, please help improve these instructions!

I assume you have installed Cygwin and MinGW, and dowloaded and
unpacked the GNUstep packages:

ffcall
gnustep-make
gnustep-objc
gnustep-base

See the GNUstep-HOWTO file for more information on where to get
various files. You need to build and install each package separately,
as described below.

1. First, start up a Cygwin BASH shell and make sure the MinGW tools
are in your path:

  export PATH=/c/mingw/bin:$PATH

(Put in whatever path you have for the mingw tools). 

NB. Using MinGW-1.1 the header file winsock2.h needed to be slightly
updated for 2000 or XP.  The size of the sa_data field in struct sockaddr
had to be increased from 14 to 22.  If you don't do this before building
the gnustep base library, the gdomap tool will not correctly determine the
internet addresses of your machine.

2. Configure and compile gnustep-make.
The default location for GNUstep on Windows systems in C:/GNUstep.
To use another location you can use the --prefix argument to configure.
First, go to the 'gnustep-make' package and configure:

  cd gnustep-make
  ./configure --target=i386-mingw32

2a.  The configure script may not have recognised that you are running in
a cygwin environment ... so you may need to edit 'fixpath.sh' to set the
CYGWIN variable to 'yes' before you build and install the make package.

3. Now build the gnustep-make package. Occationally, the make that comes
with MinGW doesn't like the way GNUstep makefiles are setup (or perhaps
it's that MingW make doesn't work with bash), so you can try
using Cygwin's make instead (/usr/bin/make instead of just make).

  make target=i386-mingw32
  make target=i386-mingw32 install

4. Now source the GNUstep.sh file so the rest of the packages will
compile correctly:

  . C:/GNUstep/System/Library/Makefiles/GNUstep.sh

Also put this command in your shell startup script. Be sure to adjust
this path to match your real GNUstep root directory if you changed it
when configuring gnustep-make.

NOTE for WIN98 users: You should also define the environment variables
HOMEDRIVE and HOMEPATH, since these aren't defined normally.

5. Compile and install the ffcall package (Version 1.8b). It's
simply a C library so it requires no special tools other than the compiler.

LD=ld RANLIB=touch ./configure --target=i386-mingw32 \
	--prefix=`$GNUSTEP_MAKEFILES/fixpath.sh -u $GNUSTEP_SYSTEM_ROOT`

which installs the libraries in the GNUstep directory structure (There is
a script in ffcall-1.8d and higher that automatically configures ffcall
and installs, called compile-mingw). Then

  make				# NOTE: Might need to be 'make LN_S=cp'
  make install

6. Now you can compile the Objective-C runtime DLL, gnustep-objc (unless 
you already have one installed):

  cd gnustep-objc
  make target=i386-mingw32 shared=yes
  make target=i386-mingw32 shared=yes install

Make sure to remove libobjc.a that comes with gcc, otherwise it will find that
one instead of the one we want. The libobjc library that comes with gcc-3.x
MAY work if you add some extra lines to the .def file, but I won't go into
that here. It's good just to use gnustep-objc.

7. Now we can configure and build the gnustep-base library.

  cd gnustep-base 
  ./configure --target=i386-mingw32 
  make target=i386-mingw32 shared=yes
  make target=i386-mingw32 shared=yes install

If you get tired of typing  "target=i386-mingw32" all the time, then before
you exec the GNUstep.sh script, just set the GNUSTEP_HOST:

  export GNUSTEP_HOST=i586-pc-mingw32
  . $GNUSTEP_SYSTEM_ROOT/Library/Makefiles/GNUstep.sh

Problems?
---------

[1] It's really important that all the libraries you link with GNUstep be
shared libraries. Even static libraries based on C (e.g. libtiff) will
prevent Objective-C modules from being loaded in Objective-C libraries.

[2] On Windows XP, at least, there are sometimes spaces in the path to the
user directory. The make program cannot deal with this.
Probably the best solution is to add a .GNUsteprc file in your home
directory with a line of the form -
GNUSTEP_USER_ROOT=/home/myname
setting your personal GNUstep root directory to be '/home/myname' ...
some path which does not contain spaces.

[3] Some users report needing to make gnustep libs like this (perhaps
when using Cygwin's gcc only):

export CC="gcc"
export CFLAGS="-mno-cygwin"
export CPPFLAGS="-mno-cygwin"
find . -name "*.lnk" -print -exec rm {} \;
make target=i386-mingw32 shared=yes LN_S="ln -s" \
  SHARED_LD_PREFLAGS="--driver-flags=\"-mno-cygwin -mdll -Wl,--enable-stdcall-fixup\" --target=i386-mingw32 --export-all-symbols"

[4] Compiling iconv (1.8):

(the part with the most problems - maybe you download it precompiled
but if you want to compile it - here is the guide) Make sure you are
compiling from a mapped drive (eg. d:) not from an UNC Path!!!!

./configure --target=i386-mingw32 --host=i386-mingw32 (ignore warnings here)
edit libtool and libcharset/libtool so that the CC variable reads 
"gcc -mno-cygwin -mdll"
make
(After a while make breaks with an error in linking)
find . -name "*.lnk" -print -exec rm {} \;
make
(make breaks now in the src folder, but the DLL is already buildt, 
that is what we need)
cp include/iconv.h $GNUSTEP_SYSTEM_ROOT/Headers
cp lib/.libs/libiconv-2.dll $GNUSTEP_SYSTEM_ROOT/Tools/libiconv-2.dll
cp lib/.libs/libiconv.dll.a $GNUSTEP_SYSTEM_ROOT/Libraries/libiconv.a

Good Sites for Pre-Compiled Binaries
------------------------------------

Many libraries, etc from:

<http://sourceforge.net/project/showfiles.php?group_id=7382>
<http://penguin.at0.net/~fredo/files/old/> (for libxml2, more?)
<http://sourceforge.net/project/showfiles.php?group_id=23617> (libtiff)

MingW guile from

<http://www.textsure.net/~ela/devel.html>.

also need guile from 

<http://sourceforge.net/project/showfiles.php?group_id=7382>

for guile-config file.

Author
------

Adam Fedor <fedor@gnu.org>