Re: [PATCH 1/2] Annotate internal_error with the attribute noreturn

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+From: Tomi Ollila <tomi.ollila@iki.fi>\r
+To: Austin Clements <amdragon@MIT.EDU>,\r
+       Justus Winter <4winter@informatik.uni-hamburg.de>\r
+Subject: Re: [PATCH 1/2] Annotate internal_error with the attribute noreturn\r
+In-Reply-To: <20120922161256.GE26662@mit.edu>\r
+References:\r
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+Date: Sat, 22 Sep 2012 23:03:40 +0300\r
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+\r
+On Sat, Sep 22 2012, Austin Clements wrote:\r
+\r
+> LGTM, though I agree with David that this should return void now, if\r
+> that's possible.\r
+>\r
+> Do we want to wrap the __attribute__((noreturn)) in an #ifdef __GNUC__\r
+> (or provide a PRINTF_ATTRIBUTE-like macro) or is that already a lost\r
+> cause?\r
+\r
+Good point -- this should be NORETURN_ATTRIBUTE instead...\r
+\r
+Also, http://gcc.gnu.org/onlinedocs/gcc-4.3.2//gcc/Function-Attributes.html states:\r
+\r
+"It does not make sense for a noreturn function to have a return type other\r
+than void."\r
+\r
+(I think that hasn't changed since :)\r
+\r
+Tomi\r
+\r
+>\r
+> Quoth Justus Winter on Sep 21 at  2:50 pm:\r
+>> Annotating functions that do not return with the noreturn attribute\r
+>> (which is understood by both gcc and clang) prevents static analyzers\r
+>> from generating false positives (internal_error is used to terminate\r
+>> the process and is used extensively in error handling code paths).\r
+>> \r
+>> Remove the return statement that was placed there to appease the\r
+>> compiler. Functions annotated with noreturn are not supposed to return\r
+>> any values.\r
+>> \r
+>> Signed-off-by: Justus Winter <4winter@informatik.uni-hamburg.de>\r
+>> ---\r
+>>  util/error_util.c |    2 --\r
+>>  util/error_util.h |    2 +-\r
+>>  2 files changed, 1 insertion(+), 3 deletions(-)\r
+>> \r
+>> diff --git a/util/error_util.c b/util/error_util.c\r
+>> index 630d228..3cf353a 100644\r
+>> --- a/util/error_util.c\r
+>> +++ b/util/error_util.c\r
+>> @@ -35,7 +35,5 @@ _internal_error (const char *format, ...)\r
+>>      vfprintf (stderr, format, va_args);\r
+>>  \r
+>>      exit (1);\r
+>> -\r
+>> -    return 1;\r
+>>  }\r
+>>  \r
+>> diff --git a/util/error_util.h b/util/error_util.h\r
+>> index bb15822..24a644b 100644\r
+>> --- a/util/error_util.h\r
+>> +++ b/util/error_util.h\r
+>> @@ -30,7 +30,7 @@\r
+>>   * Note that PRINTF_ATTRIBUTE comes from talloc.h\r
+>>   */\r
+>>  int\r
+>> -_internal_error (const char *format, ...) PRINTF_ATTRIBUTE (1, 2);\r
+>> +_internal_error (const char *format, ...) PRINTF_ATTRIBUTE (1, 2) __attribute__ ((noreturn));\r
+>>  \r
+>>  /* There's no point in continuing when we've detected that we've done\r
+>>   * something wrong internally (as opposed to the user passing in a\r
+> _______________________________________________\r
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