Re: [Mingw-cross-env-list] Question and Help

[Martin Lambers]

On Thu, 18. Mar 2010, 15:44:51 +0100, Volker Grabsch wrote:
> > and a cmake .find file,
> > maybe you want put this contribution in your website and this will be my
> > contribution to short-term.
> 
> Martin: Did you create some kind of .find file, too?

No, I do not think there should be a CMake file that tries to find
Mingw-cross-env as a whole. Instead, the existing CMake modules that
find certain packages should be told to look for them in a user-provided
directory.

> > another thing is that we should standardize the path where to get the
> > software installed by default, to write general cmake files.
> 
> I'm not a CMake expert at all, but I think a CMake file should
> never depend on any absolute path. It should never make assumption
> on where Mingw-cross-env is actually installed.

I agree completely.

> Alternative suggestion: Is it possible to write it in a way that
> it uses just one path, such as:
> 
>     cmake . -DCMAKE_FIND_ROOT_PATH=/MCE/usr/i686-pc-mingw32
> 
> That would solve the problem, too, wouldn't it?

According to <http://www.cmake.org/Wiki/CMake_Cross_Compiling>, you can
make a "toolchain file" that contains all the macros, and then call
'cmake -DCMAKE_TOOLCHAIN_FILE=...'. 

It might make sense to generate such a file in Mingw-cross-env, but it
would have to be updated if the MCE directory is moved. I do not think it
is worth the trouble.

> BTW, why can't we simply say:
> 
>     cmake . -DHOST=i686-pc-mingw32
> 
> and have cmake checking for ${HOST}-gcc and ${HOST}-pkg-config
> in the ${PATH}?

Cross compilation was only added to CMake in version 2.6, and it looks
cumbersome and incomplete to me. In my opinion, not supporting platform
triplets is a mistake.

Martin