Re: RE : RE : [lwip-devel] Can we remove pbuf_init()

[Jonathan Larmour]

Frédéric BERNON wrote:
> > #define pbuf_init() do { } while (0)
>
> I'm always suprised about this kind of macro (the do/while(0)). Most of
time, it's generate lot of warnings. Of couse, it's perhaps
compiler-dependant. I don't understand why don't write "define
pbuf_init()" ? Can you explain me when/why such code writing ?

Some times a semi-colon by itself can be a problem, and makes some 
compilers warn.

Wrapping a function-like macro in do/while (0) (which allows the 
following-semicolon to be parsed validly) is very common, and I'm 
surprised any compiler warns about it.

Jifl
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