Cross compilation discussion

[Magnus Ihse Bursie]

> OK. So you are doing what I'd usually call cross compiling, sort of, but
> you don't want to treat it as a cross-compiled build. It's an unusual
> case, in that it is cross compiled, but it is also expected to be able to
> run on the build system.

The main reason for the build to know if we're doing a cross-compilation 
or not has been if we need a special compiler to create build tools. For 
me, that is in essence what the cross-compilation flag is saying.

Separately, we have the concept of sysroot, but I agree that setting the 
sysroot is essentially a form of cross-compilation. The question is: do 
the build system need to know about this, any more than just make sure 
we pass along the sysroot properly?

Maybe this is just a question on how to present the needs of the build 
system to the user, where "cross-compilation" might have different 
connotations than are used inside the build system.

So maybe we should have like "cross-compiling-need-build-compiler" and 
"cross-complining-can-use-target-compiler"?

/Magnus