But the compiler is not the same as the --host. For example, you
might want to compile with mingw or VC++. There is a new
target in the net version of config.sub that tries to deal
with this issue.

You can now do this for VC++:

./configure CC=cl --host=windows32

As well as (assuming Mingw gcc):

./configure CC=gcc --host=windows32

Both are really cross compiles, even if the 2.50 release
does not report them as such (it is a backwards compatibility thing).