[PATCHv2] build: allow some python variable overrides

[Gustavo Zacarias]

On 02/11/2014 03:09 PM, Andrew Bartlett wrote:
> All I'm suggesting is that we should make it possible to discover and be
> consistent? Can't this somehow be done via cross-answers, or a -- option
> to configure?  I just really dislike magic environment variables.
> 
> Jeremy,
> 
> Can you give some guidance on what level of 'magic' should be acceptable
> to impose on those cross-compiling Samba?

Hi Andrew.
Doing it via cross-answers is possible, however normally the
cross-answers would be basically static according to architecture/libc
combination so modifying it on the fly wouldn't be the preferred method.
A -- option would be great, environment variables are good as well.
The acceptable 'magic' for buildroot is to try to avoid
patching/diverging too much from upstream since it makes
versions/security bumps possibly very complicated.
Take a look at: http://patchwork.ozlabs.org/patch/319241/ explicitly the
samba4.mk file to see how i'm building it at the moment.
It still needs enhancements like possibly ads support.
I can't speak for other build systems, others find patching like hell
acceptable, in buildroot we aren't that many developers and it's all
volunteer effort, hence the general attitude to avoid complicating
things to much (if it can be described in env variables, -- options or
similar is all good, that makes life easy).
Eventually, i think, the idea would be to try reduce the cross answers
file as much as possible (or even remove the need for it if that's
possible), after all samba3 did build without it with just a couple of
samba_cv_* defines that are pretty static for linux.
I'll post more patches to try to simplify the cache soon.
Regards.