Re: [PATCH] Documentation: Explain a second alternative for multi-line macros.

[Segher Boessenkool]

> > >   #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?

partial_status |=

> I don't see any uses of it

Ah, that's a separate thing -- it returns a value, it's just
never used.

> And with a small change to put it inside a do-while block
> instead of ({ ... }), it at least builds cleanly.

Well please replace it then, statement expressions should be
avoided where possible (to start with, they don't have well-
defined semantics).


Segher

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