Re: [Tuxmath-devel] tuxmath fails to compile without sdlttf

[Tasos L. <tla...@gm...>]

On 02/09/2011 02:20 AM, Volker Grabsch wrote:
> David Bruce schrieb:
>> I think the problem is in t4k_common's pkg-config file,
>> t4k_common.pc.in (reproduced below).  My knowledge of pkg-config is
>> limited, but looking at the file it's pretty clear that I hard-coded a
>> dependency on SDL_ttf into the "Libs" section.   t4k_common's build
>> process can detect if SDL_Pango is available, but the problem comes in
>> with the static linking needed for the mingw-cross-env build.  For
>> static linking, t4k_common needs to supply all the compiler arguments
>> for all the dependencies, and this only works "automagically" for
>> dependencies that themselves have pkg-config *.pc files. 
> 
> Note that a *.pc file can "Require" another package. The idea is
> that you don't have to specify anything but your own stuff in the
> "Libs" section.
> 
> However, this works only for dependencies that provide a *.pc file.
> All other libs you'll have to specify in your "Libs.private" section.
> (which will only be used for static builds, in contrast to "Libs")
> 
>> I haven't
>> figured out how to write a *.pc file that conditionally passes the
>> arguments for either SDL_Pango (plus its deps) or SDL_ttf (plus deps)
>> to the tuxmath linking step.
> 
> This is not a question of pkg-config. It is a question of Autoconf.
> If you collect some helper variables during the checks in configure.ac,
> you can simply include those variables in your *.pc.in file. (something
> like @DEP_PKGS@, @DEP_LIBS@)
> 
> In general, I recommend to check for each library whether it is
> available via pkg-config. If it isn't, try something like AC_CHECK_LIB
> as a workaround.
> 
>     PKG_CHECK_EXISTS([...],
>         PKG_CHECK_MODULES([...],
>         AC_CHECK_LIB(...)
>     )
> 

I will also look into it, see how I can help, but I don't promise as
pkg-config/Autoconf stuff are new to me..

> One final thought: Nowadays almost all libraries ship with *.pc files.
> However, some distributions like Debian don't install those, maybe
> because their build scripts were written in a time where those libraries
> didn't provide a *.pc file. I think it would be a good idea to provide
> bug reports for those distributions, but I didn't yet find the time
> to do that. Any volunteers?
> 

From a quick look here [1] only Archlinux and Fedora from the major
distributions ship SDL_ttf.pc (i dont know if this list is up-to-date
though). I could file those bug reports if the Autoconf solution doesn't
work.

> 
> Greets,
> Volker
> 

Cheers

[1]
http://pkgs.org/search/?keyword=sdl_ttf&search_on=smart&distro=0&arch=32-bit&exact=0

-- 
Tasos Latsas

GPG   : 0x219810C9 / B487 351A 6EEC B7C3 E78E  F4D9 7217 5B4B 2198 10C9
Jabber: tl...@ja...
www   : http://ttys.homelinux.net