Re: tlug: GCC compiler question

[Neil Booth <NeilB@example.com>]

Stephen J. Turnbull wrote:

[snip]
> and might or might not cause a syntax error depending on whether the
> caller's intention was
> 
>      if (true)
>         spin_lock_init(x);
>      else
>         { ... }
> 
> (which generates an "unmatched else" syntax error) or not.  Neither of
> Neil's alternatives work intuitively here.

Yes, the "if...else" construct I hadn't thought of, and is what deems
the "do..while(0)" necessary I guess.

Interestingly, now I start to understand the logic of the semicolon in
Pascal, where said problem wouldn't arise, and my {(x)->lock = 0;} would
work in all cases. I remember when I learnt Pascal (Delphi), I always
found the omission of the ";" before else statements confusing and a
PITA, coming from C.

This little exercise has taught me that Pascal is the logically correct
grammar, and C the dubious one.

Thanks Stephen,

Neil.
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