On Fri, 16 Jul 2010, Grant Likely wrote:

On Fri, Jul 16, 2010 at 2:09 PM, Catalin Marinas
[off-list ref] wrote:

quoted

On Fri, 2010-07-16 at 19:46 +0100, Linus Torvalds wrote:

quoted

On Fri, Jul 16, 2010 at 11:40 AM, Nicolas Pitre [off-list ref] wrote:

quoted

DOH.

Well, it's possible that the correct approach is a mixture.

Automatically do the trivial cases (recursive selects, dependencies
that are simple or of the form "x && y" etc), and warn about the cases
that aren't trivial (where "not trivial" may not necessarily be about
fundamentally ambiguous ones, but just "complex enough that I won't
even try").

There is still a risk with this approach when the Kconfig isn't entirely
correct. For example, on ARM we have (I pushed a patch already):

config CPU_32v6K
       depends on CPU_V6

config CPU_V7
       select CPU_32v6K

In this simple approach, we end up selecting CPU_V6 when we only need
CPU_V7. There other places like this in the kernel.

Of course, kbuild could still warn but if people rely on this feature to
select options automatically I suspect they would ignore the warnings.

In my first patch, I made Kconfig problems errors instead of warnings.
 That would prevent people from ignoring them.

ACK.


Nicolas