RE: [PATCH v5] elf: fixes compile error when both enable -Werror and -DNDEBUG

[Yang Yanchao <yangyanchao6@huawei.com>]

On 2022/4/15 15:36, Yang Yanchao wrote:
> Use -Werror and -DNDEBUG at the same time will causes the following 
> compilation errors:
> 
> cache.c: In function 'save_cache':
> cache.c:758:15: error: unused variable 'old_offset' [-Werror=unused-variable]
>   758 |       off64_t old_offset = lseek64 (fd, extension_offset, SEEK_SET);
>       |               ^~~~~~~~~~
> 
> -DNDEBUG will disables the assertion.
> Therefore, only the variables used by assertions do not take effect.
> use __attribute__ ((unused)) to disable this warning.
> ---
>  elf/cache.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/elf/cache.c b/elf/cache.c index dbf4c83a7a..e92860023c
> 100644
> --- a/elf/cache.c
> +++ b/elf/cache.c
> @@ -754,7 +754,8 @@ save_cache (const char *cache_name)
>    if (opt_format != opt_format_old)
>      {
>        /* Align file position to 4.  */
> -      off64_t old_offset = lseek64 (fd, extension_offset, SEEK_SET);
> +      __attribute__ ((unused)) off64_t old_offset
> +        = lseek64 (fd, extension_offset, SEEK_SET);
>        assert ((unsigned long long int) (extension_offset - old_offset) < 4);
>        write_extensions (fd, str_offset, extension_offset);
>      }
> 

ping again