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RE: a warning to implement

> -----Original Message-----
> From: Per Abrahamsen []
> Sent: Sunday, February 10, 2002 3:01 PM
> To:
> Subject: Re: a warning to implement
> Gabriel Dos Reis <> writes:
> > What I'm saying is that if you want to be warned about that 
> construct
> > then you should explicitly turn on the appropriate flag.  In this
> > case, I do think -Walll should -not- turn that flag on.  
> The manual says this about -Wall:
>   `-Wall'
>        All of the above `-W' options combined.  This enables all the
>        warnings about constructions that some users consider
>        questionable, and that are easy to avoid (or modify to 
> prevent the
>        warning), even in conjunction with macros.
> An example of a warning produced by -Wall:
>   void foo (const char* p, char* q)
>   {
>     while (*q = *p)
>       { ++q; ++p; }
>   }
> In function `void foo(const char *, char *)':
> warning: suggest parentheses around assignment 
> used as truth value
> It is clear that _some_ users consider assignment as truth value
> questionable, and it is easy to avoid.  Thus, it is a good example of
> a -Wall warning.  Just to set the level we are talking about.
> Are you saying the "T x = x" is less questionable or harder to work
> around than the above?
> Personally, not being one of the super programmers on this 
> list, I have
> lost a couple of days work debugging errors caused by accidental use
> of the "T x = x" construct, which I at the time didn't even knew was
> legal, so I would have loved to have had a warning with -Wall, but
> wouldn't even have thought of searching for a separate flag.

I can only agree with that :-)

However there seems to be such a strong opposition to having this warning
installed by default in -Wall that I think we should at least provide it as
an additional warning flag; it's useful enough that we may get it.

Anyway for me, that doesn't change a lot: I'm not even setting -Wall in my
makefiles: it's set up in some central place so that ALL compiles by ALL
developpers in my teams use it without even knowing that I've decided it;
thus I only have to add -Wself-initialize, or whatever it'll be called, to
this single location and all my programmers will have it :-)

I think this thread is now long enough we all refrain continuing this
religion war about whether this should be in -Wall or not (unless there is
some authoritative person that can get convinced and can rule about this

Best regards, and thanks to all for the good work.


Bernard Dautrevaux
Microprocess Ingenierie
97 bis, rue de Colombes
Tel:	+33 (0) 1 47 68 80 80
Fax:	+33 (0) 1 47 88 97 85

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