[U-Boot] [PATCH 1/2] Don't let the command-line ARCH=powerpc override our redefinition to ppc.

[Scott Wood <scottwood@freescale.com>]

Scott Wood wrote:
> Wolfgang Denk wrote:
>> Dear Scott Wood,
>>
>> In message <20091019212409.GA31322@loki.buserror.net> you wrote:
>>> The override keyword is needed for make to take our version over the one
>>> specified on the command line, and remove it from the list of command line
>>> overrides that are passed to submakes.  IMHO, the combination of "export"
>>> and "override" ought to do this automatically, but oh well.
>> I have to admit that I don't see the problem. When I explicitly ask
>> for a specific ARCH setting on the command line (versus using some
>> setting I inherited from the envrionment, eventually even unaware of
>> the current value), then I do want to use that. So the current code
>> seems to do what I would expect from it.
>>
>> Maybe my expectations are whacky, though.
>>
>> I tend to NAK this one.
> 
> For the benefit of those who weren't on the IRC channel when we 
> discussed this, I'll restate my objection.  I think you're reading too 
> much into the difference between setting ARCH with an environment 
> variable and setting it on the command line.  The number of users who 
> are going to be confused by this (at least one, since I was) is greater 
> than the number of users who would have done something useful by truly 
> forcing ARCH=powerpc (zero without other changes, since all it gets you 
> is a failed build).

BTW, the existing makefile fragment:
ifeq ($(ARCH),powerpc)
ARCH = ppc
endif

does not do anything if you pass ARCH in the environment either.  U-Boot will 
build if you pass ARCH=powerpc that way, but it will also build if you pass 
ARCH=nonsense, as whatever you specify will be replaced by include/config.mk.

-Scott