Re: [PATCH 3/3] Mark various cold functions as __COLD

[Siddhesh Poyarekar <siddhesh@gotplt.org>]

On 2023-04-29 11:06, Samuel Thibault via Libc-alpha wrote:
> It looks sensible to me indeed, any opinion from somebody else?
> 
> 
> 
> 
> Sergey Bugaev, le sam. 29 avril 2023 16:12:23 +0300, a ecrit:
>> GCC docs explicitly list perror () as a good candidate for using
>> __attribute__ ((cold)). So apply __COLD to perror () and similar
>> functions.
>>
>> Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>

LGTM.  It would be nice to do a build-many-glibcs run here since it 
touches public headers but the change itself looks fairly 
straightforward and should be fine for all compilers.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

>> ---
>>   include/error.h |  4 ++--
>>   libio/stdio.h   |  2 +-
>>   misc/err.h      | 12 ++++++------
>>   misc/error.h    |  4 ++--
>>   4 files changed, 11 insertions(+), 11 deletions(-)
>>
>> diff --git a/include/error.h b/include/error.h
>> index 9e96262f..4db67cba 100644
>> --- a/include/error.h
>> +++ b/include/error.h
>> @@ -5,11 +5,11 @@
>>   
>>   void
>>   __error_internal (int status, int errnum, const char *message,
>> -		  va_list args, unsigned int mode_flags);
>> +		  va_list args, unsigned int mode_flags) __COLD;
>>   
>>   void
>>   __error_at_line_internal (int status, int errnum, const char *file_name,
>>   			  unsigned int line_number, const char *message,
>> -			  va_list args, unsigned int mode_flags);
>> +			  va_list args, unsigned int mode_flags) __COLD;
>>   
>>   #endif
>> diff --git a/libio/stdio.h b/libio/stdio.h
>> index 45ddafdf..2387590d 100644
>> --- a/libio/stdio.h
>> +++ b/libio/stdio.h
>> @@ -859,7 +859,7 @@ extern int ferror_unlocked (FILE *__stream) __THROW __wur;
>>   
>>      This function is a possible cancellation point and therefore not
>>      marked with __THROW.  */
>> -extern void perror (const char *__s);
>> +extern void perror (const char *__s) __COLD;
>>   
>>   
>>   #ifdef	__USE_POSIX
>> diff --git a/misc/err.h b/misc/err.h
>> index 0c752465..43df3a57 100644
>> --- a/misc/err.h
>> +++ b/misc/err.h
>> @@ -32,9 +32,9 @@ __BEGIN_DECLS
>>   /* Print "program: ", FORMAT, ": ", the standard error string for errno,
>>      and a newline, on stderr.  */
>>   extern void warn (const char *__format, ...)
>> -     __attribute__ ((__format__ (__printf__, 1, 2)));
>> +     __attribute__ ((__format__ (__printf__, 1, 2))) __COLD;
>>   extern void vwarn (const char *__format, __gnuc_va_list)
>> -     __attribute__ ((__format__ (__printf__, 1, 0)));
>> +     __attribute__ ((__format__ (__printf__, 1, 0))) __COLD;
>>   
>>   /* Likewise, but without ": " and the standard error string.  */
>>   extern void warnx (const char *__format, ...)
>> @@ -44,13 +44,13 @@ extern void vwarnx (const char *__format, __gnuc_va_list)
>>   
>>   /* Likewise, and then exit with STATUS.  */
>>   extern void err (int __status, const char *__format, ...)
>> -     __attribute__ ((__noreturn__, __format__ (__printf__, 2, 3)));
>> +     __attribute__ ((__noreturn__, __format__ (__printf__, 2, 3))) __COLD;
>>   extern void verr (int __status, const char *__format, __gnuc_va_list)
>> -     __attribute__ ((__noreturn__, __format__ (__printf__, 2, 0)));
>> +     __attribute__ ((__noreturn__, __format__ (__printf__, 2, 0))) __COLD;
>>   extern void errx (int __status, const char *__format, ...)
>> -     __attribute__ ((__noreturn__, __format__ (__printf__, 2, 3)));
>> +     __attribute__ ((__noreturn__, __format__ (__printf__, 2, 3))) __COLD;
>>   extern void verrx (int __status, const char *, __gnuc_va_list)
>> -     __attribute__ ((__noreturn__, __format__ (__printf__, 2, 0)));
>> +     __attribute__ ((__noreturn__, __format__ (__printf__, 2, 0))) __COLD;
>>   
>>   #include <bits/floatn.h>
>>   #if defined __LDBL_COMPAT || __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1
>> diff --git a/misc/error.h b/misc/error.h
>> index 185b39c6..4fbd46c7 100644
>> --- a/misc/error.h
>> +++ b/misc/error.h
>> @@ -29,11 +29,11 @@ __BEGIN_DECLS
>>      If STATUS is nonzero, terminate the program with `exit (STATUS)'.  */
>>   
>>   extern void error (int __status, int __errnum, const char *__format, ...)
>> -     __attribute__ ((__format__ (__printf__, 3, 4)));
>> +     __attribute__ ((__format__ (__printf__, 3, 4))) __COLD;
>>   
>>   extern void error_at_line (int __status, int __errnum, const char *__fname,
>>   			   unsigned int __lineno, const char *__format, ...)
>> -     __attribute__ ((__format__ (__printf__, 5, 6)));
>> +     __attribute__ ((__format__ (__printf__, 5, 6))) __COLD;
>>   
>>   /* If NULL, error will flush stdout, then print on stderr the program
>>      name, a colon and a space.  Otherwise, error will call this
>> -- 
>> 2.40.1
>>
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