Re: [PATCH] plugins: fix -Werror=maybe-uninitialized false-positive

[Pierrick Bouvier]

On 1/14/25 02:48, marcandre.lureau@redhat.com wrote:
> From: Marc-André Lureau <marcandre.lureau@redhat.com>
>
> ../contrib/plugins/cache.c:638:9: error: ‘l2_cache’ may be used uninitialized 
> [-Werror=maybe-uninitialized]
>    638 |         append_stats_line(rep, l1_dmem_accesses, l1_dmisses,
>        |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Is a false-positive, since cores > 1, so the variable is set in the
> above loop.
>
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>   contrib/plugins/cache.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/contrib/plugins/cache.c b/contrib/plugins/cache.c
> index 512ef6776b..c2c274cfcd 100644
> --- a/contrib/plugins/cache.c
> +++ b/contrib/plugins/cache.c
> @@ -609,7 +609,7 @@ static int l2_cmp(gconstpointer a, gconstpointer b)
>   static void log_stats(void)
>   {
>       int i;
> -    Cache *icache, *dcache, *l2_cache;
> +    Cache *icache, *dcache, *l2_cache = NULL;
>   
>       g_autoptr(GString) rep = g_string_new("core #, data accesses, data misses,"
>                                             " dmiss rate, insn accesses,"

By the way,

which compiler (version?) are you using?
Just curious to check if we don't have any other false positives in the 
code base with it if it's a newer version.