[coreboot] typo in amdk8/raminit_f.c
ron minnich
rminnich at gmail.com
Mon Apr 13 18:25:21 CEST 2009
On Mon, Apr 13, 2009 at 9:15 AM, Peter Stuge <peter at stuge.se> wrote:
> ron minnich wrote:
>> I think this is one reason the Bell Labs crowd started using:
>> if (preprocessor_symbol == value)
>>
>> That's the C compilers job, after all ...
>>
>> The more code I see, the more I agree with them.
>
> I can see the point. But I also think excluding code from compilation
> is a big feature, especially in firmware.
ah yes, but ... just about any reasonable compiler will do something
smart with this: if (0) { ...} or if (1) { ... }.
If fact, romcc would not work at all without these types of
optimizations ... and this one is not even that aggressive.
So, since:
if (preprocessor_symbol == whatever) { ... }
is equivalent to either
if (0) {...}
or
if (1) {...}
I think it is safe to say there is no loss in code reduction.
>
> If we can do it in a smarter way, that could be good, but on the
> other hand things can be too smart as well.
What Pike et. al are really saying is "don't have cpp do something
that the C compiler can do better and with more error checking".
With which I agree.
The reason I care? Because we've had dead code for several years in
that fragment Ronald discovered, and that could have been avoided.
Scary!
ron
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