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SubjectRe: CONFIG_SMP patch updated for 2.1.61
Hi!

> Yes. "gcc -M" has various "features" that makes it completely useless for
> any real dependancy generation.
>
> - it's slow as molasses. I'm not talking "quite slow", I'm talking "so
> slow that it's pretty much useless for any reasonably sized program".
> It's essentially only useful for batch-processing.

See below.

> - it doesn't know about configuration dependencies (ie the things that
> mkdep does to warn you when the config file hasn't been properly
> included)

Ok. But I believe that creating sanitycheck batch would be acceptable
- you really do not want your sources checked each time you do make
dep.

> - it actually parses C preprocessor stuff (notably #ifdef), and because
> of that it often leaves out critical dependency information (and it
> _requires_ that you know all of the configuration at mkdep
> time).

Which is not problem, as with this architecture, you only re-do
dependencies when compiling. You no longer need mkdep phase. If
there's no dependency info for X, you need to compile X, and while
compiling X, you get dependency 'for free'. And it is ok for
dependencies to depend on config stuff with this approach.

(This is [I believe] what michael's patches 'dancing makefiles' do,
and they seem to work pretty well.)

Or I'm seriously wrong somewhere.

Pavel
--
I'm really pavel@atrey.karlin.mff.cuni.cz. Pavel
Look at http://atrey.karlin.mff.cuni.cz/~pavel/ ;-).

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