Re: GTK+3 win32/64 build environment

["Arnel A. Borja" <kyoushuu yahoo com>]

Hello,

Interesting. I'm also using cross-compiled GTK+ 3 and other libraries 
for my applications. I use the libraries/etc from the mingw32/64 project 
in OpenSUSE Build Service. I'm using GTK+ 3.6.1 though (which OBS 
currently have), I'm too busy to compile GTK+ 3.8.0 myself.

I use it to build and create NSIS installers for a payroll application, 
GPInstruct, gWaei and Anjuta.

On Wednesday, 10 April, 2013 06:50 PM, tarnyko tarnyko net wrote:
> OK folks.
> As the initial contributor of the win32 buildenv, here are my reasons 
> for preferring a native build instead of cross-compiling from Linux. 
> Sorry if it is long, but I think explaining things will help.
> First, please note that we don't have to buy a Windows license. There 
> is a *free* (as in free beer) edition of Windows named "Hyper-V 
> Server". It's stripped-down in terms of GUI, but works well for this 
> purpose.
> Here is a link to licensing stuff :
> http://social.technet.microsoft.com/Forums/en-US/winserverhyperv/thread/db3f 
> c7d7-1772-41fb-b878-4574b3c39703/
> and a screenshot of it running "gtk3-demo" while buildenv is compiling 
> GLib :
> http://www.tarnyko.net/repo/hyperv_gtk3.png

I don't know that there's a free version of Windows :D.

> Short version : cross-compiling GTK+3 is a headaches generator. It's 
> not easy nor efficient, and hard to maintain.

I agree, it is hard to maintain. Though I still prefer 
cross-compilation, since it's faster in compiling. I sometimes fell 
asleep while compiling in MinGW in native Windows.

> Long version with individual points for techs :
> - MinGW/GCC for Windows is a standalone compiling environment : 
> basically, you just drop all files in a directory, and it will work, 
> regardless of the OS version you are using. That's because most of the 
> base utils and libraries are compiled statically.

Is it really compiled statically? I don't see any difference when I 
moved from native MinGW to OBS. Some packages are static, most are not. 
Or atleast the old GTK+ 2 builds in www.gtk.org have most of libraries 
compiled dynamically.

> MinGW under Linux is mostly installed via a package manager ("yum 
> install mingw32-gcc-c++" on Fedora e.g.). You don't get to choose 
> which version of the compiler you install. Same thing for the 
> dependencies (libtool, expat, perl, python...). These versions are 
> likely to change regarding the distro your are using, and you cannot 
> copy their files from one computer to another because binaries are 
> compiled dynamically (= depend on this particular box' libc a.s.o).

Cross-compiled GTK+ and other libraries use msvcrt, so usually the 
difference in compiler versions is not a problem except for libstdc++.

I'm using Ubuntu, and use the builds for 32-bit and 64-bit Windows that 
are built using OpenSUSE 12.3. I mix my libraries and programs compiled 
using GCC 4.6.3 with the ones from OBS that use GCC 4.8.0. Seems to work 
fine (I've been using them for two years now, I think), except that you 
should make sure that you use the libstdc++ that comes with your 
compiler (though it is used by g++, not gcc, and there are no GTK+ 
dependency that use g++, I believe; I only got this problem last week 
when I started porting Anjuta since its C++ parser uses g++).

The problem might be python though, the cross-compiled Python that OBS 
uses are quite old (2.6). I don't use python so I'm not sure how big the 
impact would be, but you could compile the base GTK+ stack without python.

> That means you depend on a precise distro version.

I recently moved from the builds for OpenSUSE 12.1 to 12.3 (and did that 
before many times before), upgraded my system many times too (since 
Ubuntu Oneiric I think), and been using it for about 2 years, so I don't 
think it is a problem. And I still use the packages I compiled myself 
before along with the newer set of libraries, seems like there are no 
problems.

> Plus, my tests have proven that it matters while building. There are 
> some fixes for libtool and the compiler itself in the buildenv (see 
> the 64-bit one) ; if you use a different version, it will sometimes 
> break the build.
> A solution would be to have a standalone MinGW install for Linux. I've 
> googled for one without success. If one doesn't exist, the ultimate 
> solution whould be to create one by recompiling MinGW statically 
> myself, that means recompiling the compiler : I don't know anything 
> about that, it will take lots of time.

Ubuntu, Fedora and OpenSUSE have the cross-compilers in their repos. OBS 
uses MinGW-w64 GCC 4.8 while I use MinGW-w64 GCC 4.6.3 in Ubuntu. I use 
their builds alongside each other. A year before I even combine MinGW-32 
and MinGW-w64 builds, though I thought that might be a bad idea, and 
Ubuntu has MinGW-w64 cross-compilers anyway. If you want to build 
MinGW-w64, you could check OBS which have the most recent GCC 
cross-compilers.

> - GTK+3 build process sometimes needs to run the binaries it has just 
> generated.
> For instance, it runs "glib-compile-schemas" on its XML files to 
> create the "schemas.compiled" catalog. Without it, GTK+ programs won't 
> run.
> You cannot obviously run Win binaries under Linux -and using wine is 
> not an option here. The only way is to generate, at the same time, the 
> Linux version of the same binary ; that is to say, generate the stack 
> *twice*. One time you obtain "glib-compile-schemas" for Linux, put it 
> safe somewhere, then later during the Windows build you tell it to use
> *this* particular binary at this particular point. Ugly patches. Or 
> you let the end-user do this, which is not user-friendly.

OBS uses the native tools that come with the build system while 
cross-compiling the packages. Package mingw32-glib2, while being built 
by OBS, uses the tools from the glib2* packages (which the build system 
will already have by default). This way gschemas.compiled is only needed 
before running applications, since the build system will use its native 
tools.

> - You won't be able to test and Q/A the binaries you just produced.
> Wine cannot be used because it's not reliable with GTK+3 ; last time I 
> tried under Debian, fonts were disproportional and pictures sometimes 
> stripped. You have to run them on a native Windows OS.
> I think I have covered the most important points ; opinions and 
> arguments are welcome. I'm sometimes available on IRC channel for 
> discussions, too.

I use GTK+ 3 in Wine. Just install gnome-themes-standard (actually, 
compile first since it is not in OBS), then set Adwaita as theme. The 
default theme sucks in Wine (and sometimes in Windows too, so I use 
Adwaita in my installers).

The problem with the pictures is probably related to the loading of 
gdk-pixbuf loaders. Probably the loaders cache is not created yet.

The reason why I like the builds from OBS is that they are already 
separated and most libraries are already available. I just pick which do 
I want to install. The only libraries and programs that I need to 
compile myself are gdl, glade, gnome-themes-standard, gtksourceview, 
libgda and libgee (gdl, glade and gtksourceview are dependencies of 
Anjuta; I use libgda and libgee for the payroll application that I built 
that we use at the office where I work.). Then I just run a script that 
calls a modified download-mingw-rpm.py, fixes the pkg-config path, 
builds the schemas, reinstalls my compiled packages, fills the GTK+ 2 & 
3 settings and copies the libstdc++ of my compiler, then I could build 
and test my programs.

Sorry for a very long response. I'm not even sure if I was able to 
explain things properly.


Regards,

Arnel