Am 29.01.2013 11:03, schrieb Markus Armbruster:
> Andreas Färber <afaer...@suse.de> writes:
>
>> b) Working around an issue resulting from hiding C statements inside a
>> preprocessor macro is totally backwards compared to properly using the C
>> language in the first place. Its mechanism for reuse are functions, and
>> for performance considerations static inline functions.
>
> Nobody denies inline functions are to be preferred in many cases.
>
> Valid exceptions include cases where we want genericity, which a macro
> can easily provide, but an inline function can't.
>
>> Therefore I disagree with you that b) is not an entirely different
>> disussion as you repeatedly suggest and that according to a) it is not
>> *generally* necessary to put do { ... } while (0) into any random macro
>> that one writes. It depends on the contents and on the context.
>
> I don't think Peter suggested to put do ... while (0) into random
> macros! He asked to put it exactly into *statement-like* macros, as per
> standard C practice. Most macros are expression-like.
Quoting PMM from last night:
<<<
"do ... while (0)" is completely standard practice
for writing robust macros in C. Patches which don't do that
should fail code review.
>>>
This is what sparked the most heated part of this debate! I completely
object to this generalized statement without restriction to
statement-like macros.
> I think you're overstating your case. Statement-like macros should be
> rare.
This RFC was just a beginning. An average 50%+ of per target-*/ files
contained macros that were touched here. Even more files are in hw/. Per
file it was up to ~5 such macro definitions. And my main issue is
deriving a convention for new files from this discussion.
Andreas
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