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Message-ID: <9ebd65110408171721146dd77@mail.gmail.com>
Date: Wed, 18 Aug 2004 00:22:00 -0000
From: Adam Monsen <haircut@gmail.com>
Reply-To: Adam Monsen <haircut@gmail.com>
To: Gabor Greif <gabor@mac.com>
Subject: Re: warn/croak on "string" "string" auto-joins
Cc: gcc@gcc.gnu.org
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Hi Gabor,

Thanks for your input!

On Wed, 18 Aug 2004 01:25:10 +0200, Gabor Greif <gabor@mac.com> wrote:
> Adam Monsen <haircut at gmail dot com> wrote:
>  > String auto-joins can be dangerous. Is there a way to tell the
>  > compiler to warn/croak when an auto-join occurs?
>  >
>  > For instance, find the bug in this code:
>  >
>  > char *months[] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul",
>  > "Aug" "Sep", "Oct", "Nov", "Dec"};
>  >
>  > If not, I'd like to suggest a way to ask the compiler to strictly
>  > check for this.
> 
> The compiler cannot shield you from all programmer errors.

Agreed.

> This would have helped early and is good practice:
> 
> char *months[12] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul",
> "Aug" "Sep", "Oct", "Nov", "Dec"};
> 
> --> high probability warning

I'm not sure I understand, what does "high probability warning" mean?
I get no errors/warnings from the following:

#include <stdio.h>
int main( void )
{
  char *months[15] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul",
"Aug" "Sep", "Oct", "Nov", "Dec"};
  printf("7: %s\n", months[8]);
  return 0;
}

compiled with 'gcc -Wall -pedantic -ansi', using GCC 3.3.3.

> Cheers,
> 
>     Gabor
> 
> PS: I often assemble longer (format) strings from smaller ones
> by means of macros, so if this ever to become a warning I'd
> prefer to exclude macro-expanded occurrences.

But you currently have no use for the warning, correct? Or, do you
feel it is useful? I'm confused.

-- 
Adam Monsen <adamm@wazamatta.com>
http://adammonsen.com/