[Mingw-cross-env-list] Qt for mingw-cross-env

[Mark Brand]

Hi,

I have put together a makefile and patch for building Qt 4.6 "Technology 
Preview 1" in mingw-cross-env.  Volker has a copy, and if he likes it I 
hope it will find its way into the repo, be useful, and improve through 
feedback.

The 2 main tricks are 1) building a minimal native Qt so we have the 
tools (qmake, moc, etc) we need, and 2) hacking the build system so we 
can use the configure script for the mingw32 target system.  The 
configure script from Qt supports cross compiling for some targets, but 
not mingw32.

This is based on the method found here
http://divided-mind.blogspot.com/2007/09/cross-compiling-qt4win-on-linux.html

Qt.mak builds a static release version, which I think is consistent with 
the philosophy of mingw-cross-env. But it's pretty easy to change to 
shared linking and/or debug libraries for users who are so inclined 
(like me).

Volker's remarks and my responses follow:

> I think that this discussion should go on the mailing list.

Yes.

> Thanks for your great amount of work. As I'll have to
> cross compile a Qt application for Windows in the near
> future, this could be the first contribution which helps
> _me_, personally, not "just" the project.

That's nice to hear. I'm glad to give something back to the project that 
you have invested a lot of effort into.

> BTW, didn't I send you my previous work on Qt as a starting
> point? I hope I did. For the reference, I attached it to this
> mail.

Yes, I saw it then, and I've looked at again just now. Both yours and 
mine use the configure script.  Another approach, seen in the Fedora and 
Suse RPMs, runs the binary configure.exe under Wine.

> I wonder why you're using the qt-everywhere-* stuff instead
> of just the qt-win-* package. Is there any special reason
> for that?

Since Qt 4.6 there is just one unified source package for all platforms. 
 Nokia is keen to introduce new platforms, so I guess the unified 
source package simplifies things.  Actually this comes in handy for 
cross building, since we have to build both a native Qt and the 
win32-g++ Qt.