On Mon, May 18, 2026 at 09:33:31AM -0700, Stephen Hemminger wrote:
> Newer GCC warns when a non-boolean constant is an operand of &&, which
> trips whenever RTE_IS_POWER_OF_2 is used in a static_assert with a
> power-of-two literal. Make the zero check explicit.
>
> Fixes: 7c872b96983a ("hash: validate hash bucket entries while compiling")
> Cc: [email protected]
>
> Signed-off-by: Stephen Hemminger <[email protected]>
Acked-by: Bruce Richardson <[email protected]>
One further suggestion below, since you are changing this.
> ---
> lib/eal/include/rte_bitops.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/lib/eal/include/rte_bitops.h b/lib/eal/include/rte_bitops.h
> index aa6ac73abb..d2719ecd5e 100644
> --- a/lib/eal/include/rte_bitops.h
> +++ b/lib/eal/include/rte_bitops.h
> @@ -1299,7 +1299,7 @@ rte_fls_u64(uint64_t x)
> /**
> * Macro to return 1 if n is a power of 2, 0 otherwise
> */
> -#define RTE_IS_POWER_OF_2(n) ((n) && !(((n) - 1) & (n)))
> +#define RTE_IS_POWER_OF_2(n) ((n) != 0 && !(((n) - 1) & (n)))
>
I'd also suggest changing the second part of the && to match, changing the
"!" for explicit "== 0":
#define RTE_IS_POWER_OF_2(n) ((n) != 0 && (((n) - 1) & (n)) == 0)
> /**
> * Returns true if n is a power of 2
> --
> 2.53.0
>
