On April 16, 2025 11:16:45 PM PDT, Ard Biesheuvel <a...@kernel.org> wrote:
>On Thu, 17 Apr 2025 at 00:01, Kees Cook <k...@kernel.org> wrote:
>>
>> GCC 15's new -Wunterminated-string-initialization notices that the 16
>> character lookup table "zero_uuid" (which is not used as a C-String)
>> needs to be marked as "nonstring":
>>
>> drivers/md/bcache/super.c: In function 'uuid_find_empty':
>> drivers/md/bcache/super.c:549:43: warning: initializer-string for array of
>> 'char' truncates NUL terminator but destination lacks 'nonstring' attribute
>> (17 chars into 16 available) [-Wunterminated-string-initialization]
>> 549 | static const char zero_uuid[16] =
>> "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";
>> |
>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>
>> Add the annotation to silence the GCC warning.
>>
>> Signed-off-by: Kees Cook <k...@kernel.org>
>> ---
>> Cc: Coly Li <col...@kernel.org>
>> Cc: Kent Overstreet <kent.overstr...@linux.dev>
>> Cc: linux-bca...@vger.kernel.org
>> ---
>> drivers/md/bcache/super.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
>> index e42f1400cea9..577d048170fe 100644
>> --- a/drivers/md/bcache/super.c
>> +++ b/drivers/md/bcache/super.c
>> @@ -546,7 +546,7 @@ static struct uuid_entry *uuid_find(struct cache_set *c,
>> const char *uuid)
>>
>> static struct uuid_entry *uuid_find_empty(struct cache_set *c)
>> {
>> - static const char zero_uuid[16] = "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";
>> + static const char zero_uuid[] __nonstring =
>> "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";
>>
>
>Just
>
>static const char zero_uuid[16] = {};
>
>should work fine here too. No need for the initializer.
🤦 Yes. This is what I get for fixing dozens of these. I'll send a v2...
-Kees
--
Kees Cook
