Re: [patch] 2.6.0-test5: serio config broken?

[Tom Rini <trini@kernel.crashing.org>]

On Sat, Sep 13, 2003 at 05:22:16PM +0900, Norman Diamond wrote:

> Although I can't keep up with the mailing list, I saw this from Adrian Bunk:
> > On Thu, Sep 11, 2003 at 04:04:48PM -0700, Tom Rini wrote:
> > >
> > > Okay.  The following Kconfig illustrates what I claim to be a bug.
> > > config A
> > > bool "This is A"
> > > select B
> > > config B
> > > bool "This is B"
> > > # Or, depends C=y
> > > depends C
> > > config C
> > > bool "This is C"
> > >
> > > Running oldconfig will give:
> > > This is A (A) [N/y] (NEW) y
> > > This is C (C) [N/y] (NEW) n
> > > And in .config:
> > > CONFIG_A=y
> > > CONFIG_B=y
> > > # CONFIG_C is not set
> 
> This is a problem.  Proposed solution follows later.
> 
> > > I claim that this should in fact be:
> > > CONFIG_A=y
> > > CONFIG_B=y
> > > CONFIG_C=y
> 
> Even for this simple case, there are other possibilities.  When we add human
> logic to the specified sequence of events then we can say that your
> interpretation is most likely what the user wanted, but in ordinary logic
> there are other possibilities such as n, n, n.  Proposed solution follows.
> 
> > The problem is that select ignores dependencies.
> > Unfortunately, your proposal wouldn't work easily, consider e.g.
> > config A
> > bool "This is A"
> > select B
> > config B
> > bool
> > depends C || D
> > config C
> > bool "This is C"
> > depends D=n
> > config D
> > bool "This is D"
> > Do you want C or D to be selected?
> 
> If neither is selected, then the problem is essentially the same as the one
> which Mr. Rini pointed out.  And again there are other possible
> possibilities such as n, n, n, n.
> 
> Solution:  Surely plain "make" could start by checking dependencies.  Or
> maybe "make dep" could be reincarnated.  If there is any inconsistency, then
> the Makefile could issue an error and refuse to start compiling.
> 
> This has the added benefit that if the human has some reason to edit the
> .config file by hand instead of using a make [...]config command, plain
> "make" will have a chance of catching editing errors.
> 
> This doesn't automate a solution as thoroughly as either of you were hoping
> for; it honestly admits that it can't read the human's mind  :-)

Yes, even that would work quite nicely, perhaps while saying what the
specific problem is as well.  Roman, how hard would this be to do?

-- 
Tom Rini
http://gate.crashing.org/~trini/