[cmake-developers] Cross compiling toolchain variables

[Stephen Kelly]

Stephen Kelly wrote:

>> We'll have to resolve this while combining CMAKE_SYSROOT and
>> CMAKE_OSX_SYSROOT.
> 
> Yes, I think so too.

Thinking more about this, I'm leaning towards keeping these variables 
separate. 

I was trying to figure out what the user-story would be for a merged 
feature. Either:

1) The user sets the CMAKE_SYSROOT to a path *or* a OSX SDK name. CMake 
transforms it to a path if it is an SDK name, so that in CMake code, 
CMAKE_SYSROOT is always a path.

2) The user continues to set CMAKE_OSX_SYSROOT, but CMake sets the 
CMAKE_SYSROOT variable to either the path, if it is a path, or the 
transformed result of an SDK name.

The (1) option seems odd to me. I guess there is precedent, in that

 cmake .. -DCMAKE_CXX_COMPILER=g++-4.6

and 

 message("COMPILER ${CMAKE_CXX_COMPILER}")

prints 

 COMPILER /usr/bin/g++-4.6

But still, I'd prefer not going with option 1.

Option 2 is no better than not merging these features at all.

So, I think, without knowing more than the above, I prefer option 3: Don't 
merge the features.

Thanks,

Steve.