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SubjectRe: [PATCH] Documentation: Explain a second alternative for multi-line macros.
Segher Boessenkool wrote:
>>> In this case, the second form
>>> should be used when the macro needs to return a value (and you can't
>>> use an inline function for whatever reason), whereas the first form
>>> should be used at all other times.
>>
>> that's a fair point, although it's certainly not the coding style
>> that's in play now. for example,
>>
>> #define setcc(cc) ({ \
>> partial_status &= ~(SW_C0|SW_C1|SW_C2|SW_C3); \
>> partial_status |= (cc) & (SW_C0|SW_C1|SW_C2|SW_C3); })
>
> This _does_ return a value though, bad example.

Where does it return a value? I don't see any uses of it
in arch/i386/math-emu/* that use it as returning a value.
And with a small change to put it inside a do-while block
instead of ({ ... }), it at least builds cleanly.
I expected some complaints.
--
~Randy
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