Re: [PATCH 2/5] arm/digic: fix format-truncation warning

[Thomas Huth <thuth@redhat.com>]

On 28/03/2022 10.47, marcandre.lureau@redhat.com wrote:
> From: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> ../hw/arm/digic.c: In function ‘digic_init’:
> ../hw/arm/digic.c:45:54: error: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 5 [-Werror=format-truncation=]
>     45 |         snprintf(name, DIGIC_TIMER_NAME_MLEN, "timer[%d]", i);
>        |                                                      ^~
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>   hw/arm/digic.c | 5 +----
>   1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/hw/arm/digic.c b/hw/arm/digic.c
> index 614232165cdc..6df554797734 100644
> --- a/hw/arm/digic.c
> +++ b/hw/arm/digic.c
> @@ -39,10 +39,7 @@ static void digic_init(Object *obj)
>       object_initialize_child(obj, "cpu", &s->cpu, ARM_CPU_TYPE_NAME("arm946"));
>   
>       for (i = 0; i < DIGIC4_NB_TIMERS; i++) {
> -#define DIGIC_TIMER_NAME_MLEN    11
> -        char name[DIGIC_TIMER_NAME_MLEN];
> -
> -        snprintf(name, DIGIC_TIMER_NAME_MLEN, "timer[%d]", i);
> +        g_autofree char *name = g_strdup_printf("timer[%d]", i);
>           object_initialize_child(obj, name, &s->timer[i], TYPE_DIGIC_TIMER);
>       }
>   

DIGIC4_NB_TIMERS is 3 ... so the compiler should also be able to see that 
the string fits fine into the name[] array here. That really sounds like 
your GCC 12.0 is buggy. Please open a compiler bug ticket.

  Thomas