Date: Sat, 22 Sep 2012 12:12:56 -0400
From: Austin Clements <amdragon@MIT.EDU>
To: Justus Winter <4winter@informatik.uni-hamburg.de>
Subject: Re: [PATCH 1/2] Annotate internal_error with the attribute noreturn
Message-ID: <20120922161256.GE26662@mit.edu>
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LGTM, though I agree with David that this should return void now, if
that's possible.

Do we want to wrap the __attribute__((noreturn)) in an #ifdef __GNUC__
(or provide a PRINTF_ATTRIBUTE-like macro) or is that already a lost
cause?

Quoth Justus Winter on Sep 21 at  2:50 pm:
> Annotating functions that do not return with the noreturn attribute
> (which is understood by both gcc and clang) prevents static analyzers
> from generating false positives (internal_error is used to terminate
> the process and is used extensively in error handling code paths).
> 
> Remove the return statement that was placed there to appease the
> compiler. Functions annotated with noreturn are not supposed to return
> any values.
> 
> Signed-off-by: Justus Winter <4winter@informatik.uni-hamburg.de>
> ---
>  util/error_util.c |    2 --
>  util/error_util.h |    2 +-
>  2 files changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/util/error_util.c b/util/error_util.c
> index 630d228..3cf353a 100644
> --- a/util/error_util.c
> +++ b/util/error_util.c
> @@ -35,7 +35,5 @@ _internal_error (const char *format, ...)
>      vfprintf (stderr, format, va_args);
>  
>      exit (1);
> -
> -    return 1;
>  }
>  
> diff --git a/util/error_util.h b/util/error_util.h
> index bb15822..24a644b 100644
> --- a/util/error_util.h
> +++ b/util/error_util.h
> @@ -30,7 +30,7 @@
>   * Note that PRINTF_ATTRIBUTE comes from talloc.h
>   */
>  int
> -_internal_error (const char *format, ...) PRINTF_ATTRIBUTE (1, 2);
> +_internal_error (const char *format, ...) PRINTF_ATTRIBUTE (1, 2) __attribute__ ((noreturn));
>  
>  /* There's no point in continuing when we've detected that we've done
>   * something wrong internally (as opposed to the user passing in a