Re: svn commit: r1936828 - in apr/apr-util/branches/1.6.x: . crypto

Hi Eric and all,

Am 03.08.26 um 15:45 schrieb [email protected]:
> Author: covener
> Date: Mon Aug  3 13:45:25 2026
> New Revision: 1936828
> 
> Log:
> Merge r1936827 from aprutil 1.7.x:
> 
> hide __has_attribute on traditional xlc platforms
> 
> The backport of 1917748 omitted this in apr.h on purpose,
> but this is a new/narrow usage and not in a header
> where it would taint anyones use of __has_attribute.
> 
> Modified:
>     apr/apr-util/branches/1.6.x/   (props changed)
>     apr/apr-util/branches/1.6.x/crypto/   (props changed)
>     apr/apr-util/branches/1.6.x/crypto/apr_passwd.c
> 
> Modified: apr/apr-util/branches/1.6.x/crypto/apr_passwd.c
> ==============================================================================
> --- apr/apr-util/branches/1.6.x/crypto/apr_passwd.c	Mon Aug  3 13:44:19 2026	(r1936827)
> +++ apr/apr-util/branches/1.6.x/crypto/apr_passwd.c	Mon Aug  3 13:45:25 2026	(r1936828)
> @@ -64,6 +64,12 @@ static volatile const apr_uint32_t optbl
>    * Paper:
>    *   https://cr.yp.to/papers/cryptoint-20250424.pdf
>    */
> +#if (defined(__xlc__) && !defined(__GNUC__))
> +#ifndef __has_attribute
> +#define __has_attribute(__x)    0
> +#endif
> +#endif
> +
>   #if __has_attribute(always_inline)
>   __attribute__((always_inline))
>   #endif
I also get compilation errors due to __has_attribute() when compiling 
with older gcc compilers. Due to

https://gcc.gnu.org/onlinedocs/cpp/_005f_005fhas_005fattribute.html

I would suggest a more general check like this:

--- crypto/apr_passwd.c	2026-08-03 15:45:25.000000000 +0200
+++ crypto/apr_passwd.c	2026-08-09 20:56:18.478871355 +0200
...
-#if (defined(__xlc__) && !defined(__GNUC__))
  #ifndef __has_attribute
  #define __has_attribute(__x)    0
  #endif
-#endif
  ...


Would that be OK for your xlc environment as well?

I would then also apply this to crypto/apr_crypto.c which contains 
another copy of test_nonzero_timingsafe() and thus also uses 
__has_attribute().

Thanks and regards,

Rainer